Ecological Restoration of Habitats Based on Avian Diversity and Landscape Patterns—A Case Study of Haining Mining Pit Park in Zhejiang, China

Abstract

The development of the mining park has impacted the richness of bird diversity. Coordinating the harmonious coexistence of humans and birds is a core issue for the sustainable development of the mining park. This study aims to investigate the relationship between landscape patterns and bird diversity and propose ecological restoration strategies for the mining park. Through field surveys and fixed-transect methods, the existing dominant bird species in the mining park were surveyed. The Shannon index was used to analyze the level of bird diversity in the mining park. A site plan of the mining park was drawn, and ArcGIS 10.8 and Fragstats 4.2 software were used to statistically analyze the landscape patterns of the mining park. The results of the two data sets were compared and analyzed to determine the relationship between landscape patterns and bird diversity. A total of eight landscape types were identified, and diversity indices, including the H (Shannon diversity index), F (species richness index), G (genus richness index), and G-F indices, were calculated. Existing issues in the site include diverse aquatic landscape types but poor connectivity, heterogeneous rocky landscape, bird habitat degradation, and frequent human interference. Proposed solutions include building ecological floating islands (habitat-type floating islands, restoration-type floating islands) to connect patches; comprehensive restoration combining full and partial restoration to restore bird habitats and increase vegetation coverage of rocky patches; low human interference design through ecological protection control zones, landscape functional zones, and park road design to create an environment for bird habitats and a mining park landscape suitable for leisure recreation, creating a new home for cohabitation between humans and birds. The research results indicate that landscape pattern diversity, heterogeneity, fragmentation, and human interference affect the richness of bird diversity. Ecological restoration, plant cultivation, and zoning planning can transform the site, enhance the landscape, and provide theoretical support and practical guidance for the creation of habitats for similar bird species.

1. Introduction

While constructing the mine pit park, simultaneous large-scale development has impacted the ecological chain, disrupting the habitats of birds. The quality of habitats directly influences bird distribution, population density, and reproductive success. Constructing suitable habitats holds significant importance in preserving bird diversity and enhancing the ecological environment in both urban and rural areas [1]. According to the varied habits and environmental requirements of different bird species, bird ecological populations can be categorized into Natatores, Grallatores, Passeres, Scansores, Terrestores, and Raptors [2,3,4,5]. Natatores, adept at swimming, diving, and rapid flight, generally inhabit areas near lakes, with a high demand for aquatic habitat quality. Grallatores, not proficient in swimming, prefer nesting in tall trees near water and forage on shores [6]. Passeres, typically small-sized birds known for their vocalizations, mostly inhabit trees, with a few ground-dwelling species [2,7,8,9]. Scansores are predominantly active in sparse forests, grasslands, and open water and feed on insects in tree canopies, with their hunting influenced by the growth of trees [6,7]. Terrestores, typically active on land, mainly feed on plants, are not adept at flying, and are commonly found in cultivated land and shrubbery and around residential areas [10]. Raptors, primarily consuming birds and mammals, are adapted for capturing and tearing apart their prey, often perching on tree branches [11]. Therefore, the conservation of bird diversity can be achieved by considering their habits and rational planning and utilization of habitat landscape patterns [2].

Bird habitats are the places where birds grow and develop, providing essential elements such as food and water necessary for their survival [6]. Simultaneously, these habitats meet the needs of birds for reproduction and refuge under certain conditions [5]. The primary influencing factors on bird habitats can be categorized into natural and human-related aspects [4]. Natural factors encompass climate, topography, water bodies, soil, vegetation, and more, while human-related factors involve planning, construction, production, and other negative influences resulting from both natural and human sources. The spatial activities of birds vary based on differences in the ecological elements, bird behavior, and sensitivity of bird species.

Landscape pattern analysis is a central concern within landscape ecology. Landscape pattern refers to spatial arrangements, namely, the combination and arrangement of various-sized landscape elements in space [12,13]. The diversity of species is closely related to landscape patch heterogeneity, fragmentation, and diversity [14,15,16,17]. Birds, being highly reliant on environmental food sources and habitats, are particularly susceptible to the characteristics of landscape patterns [18]. This study calculates landscape pattern indices in Haining Mine Pit Park, including the number of landscape patches, patch area, and average patch area, to determine the distribution form of landscape patterns and assess their impact on bird diversity.

Habitat ecological restoration refers to a series of measures taken to restore or improve the natural condition and functionality of a specific ecosystem or habitat [19]. This includes setting habitat restoration goals, assessing habitat quality, developing restoration strategies, conducting monitoring and evaluation, and ongoing management [19]. This process aims to promote the conservation and restoration of biodiversity, enhance the health and functionality of ecosystems, and improve the environmental quality of human communities [20]. Habitat ecological restoration is crucial for the protection of endangered species, the prevention of land degradation, the reduction of risks from floods and droughts, and the provision of ecological services, among other things [21].

In recent years, scholars have made significant progress in creating habitats for birds, primarily focusing on evaluating the value of different habitats for birds and species preferences for habitats [1,3,4,5,6,11,22,23,24,25,26,27,28,29,30]. However, research on landscape patterns, both domestically and internationally, has mostly concentrated on the analysis of landscape pattern characteristics and dynamic evolution processes [12,15,18,31,32]. There has been relatively little research that combines bird habitats with landscape patterns. Huang, P. (2022), for instance, explored the impact of landscape features (patches, landscape, and surrounding environment indices) on bird communities using urban parks as the study object [33]. The results indicated that park morphological indices positively influenced bird alpha diversity and resident bird abundance. The study suggested that urban park construction and planning should aim to expand park areas and increase forest proportions and irregular coastlines. However, compared to urban parks, mine pit parks possess unique topographical structures and ecological niches. Difficulty in obtaining terrain data for the site, coupled with a lack of systematic ecological planning, makes mine pit parks less operationally suitable as bird habitats. Building upon previous research, this paper, through an analysis of the relationship between different landscape patterns in mine pit parks and bird diversity, proposes the integration of bird habitat construction with habitat ecological restoration. The goal is to reshape the landscape of Haining Mine Pit Park in Zhejiang, focusing on creating bird habitats. Starting from landscape patterns and aiming to protect bird diversity, the paper suggests using minimally invasive, low-impact methods to provide habitats for birds. Through habitat restoration, including the creation of buffer zones and ecological floating islands, the natural ecological patterns within the site can be restored. This approach serves as a reference for transforming similar mine pit parks into bird habitats.

2. Materials and Methods

This paper adopts a combined research approach involving avian diversity indices and landscape pattern indices. Firstly, avian diversity was surveyed using fixed-transect lines to obtain information on bird species and quantities in the study area. Subsequently, the SPSS 26.0 software, in conjunction with the Shannon–Wiener index, was employed to calculate the avian diversity index (H), family (F) diversity index, genus (G) diversity index, and G-F index. Secondly, a landscape type survey was conducted utilizing GlobeLand30 and GPS to determine the landscape types of the sites, which were then mapped into CAD drawings. Furthermore, the CAD drawings were imported into GIS for land-use reclassification, resulting in GIS data. The GIS data were then input into Fragstats 4.2 to obtain landscape pattern indices. Finally, based on the landscape types, a habitat assessment for birds was conducted in the pre-transformed study area to determine the necessity of the transformation. After completing these foundational preparations, further steps involved predicting the relationship between avian diversity and landscape structure and assessing whether the transformed quarry park meets the conditions for bird habitat. In studying the relationship between avian diversity and landscape structure, a multiple linear regression model was applied for prediction to discern the inherent connections. For evaluating the habitat conditions of the transformed quarry park, the feasibility of the study was verified through disturbance assessment (Figure 1).

2.1. Overview of the Study Area

The study area is located in the southeastern part of Haining City, Zhejiang Province, China, in Yuanhua Town (30° N, 120° E) (Figure 2). It comprises three sections: Baojiashan, Shenfunshan, and Dashanwan Village, including four mine pits that have been filled with water to form lakes—East Lake, South Lake, West Lake, and North Lake (tentatively named). The total surveyed area within the research site is 152.1 hectares. The region features a north subtropical maritime humid climate, characterized by mild temperatures and abundant precipitation. During the cold season, prevailing winds come from the north to northwest, resulting in a dry and chilly climate with relatively low precipitation. The area experiences distinct seasons, with longer winters and summers and shorter spring and autumn periods. The surface vegetation cover is sparse, with a tendency for arid and warm conditions, leading to the formation of temporary water bodies like vernal pools. This area serves as an ecotone for various habitats due to its diverse conditions, making it a challenging but potentially rich environment. However, prolonged mineral industry development has led to habitat homogenization, resulting in a decline in bird diversity.

According to a survey of animal resources in the entire county in 1994, Haining City has 208 families and 500 species of animals. Birds are the most diverse group, with approximately 124 families and over 300 species of invertebrates and 74 families with around 200 species of vertebrates. Domesticated poultry and livestock include pigs, cows, sheep, rabbits, dogs, cats, chickens, ducks, geese, and pigeons. There are also abundant freshwater fish resources, with a variety of species such as carp, grass carp, crucian carp, common carp, catfish, and goldfish, as well as other aquatic products like turtles, tortoises, crabs, and shrimp. Wildlife is diverse, with over 60 species of mammals, including hedgehogs, small Chinese pipistrelles, horned Chinese pipistrelles, and Pipistrellus javanicus. There are more than 270 species of birds, including red-throated loons, green-throated loons, great egrets, egrets, crows, and ravens. Reptiles include flat-shelled turtles, tortoises, and stone lizards, with over 50 species. Amphibians include the oriental fire-bellied newt, Chinese fire-bellied toad, and spotless rain frog, totaling 16 species. Fish species include large silver carp, Taihu new silver carp, and crucian carp, with over 70 species. Arthropods include spiders, crustaceans, myriapods, and arachnids.

2.2. Research Methods

2.2.1. Bird Survey

(1)

Bird Survey Methods

The research was conducted during two periods: from April to May and from October to November in 2022, coinciding with the migratory seasons of birds. The observation times were set in the early morning from 6:00 to 8:00 and evening from 18:00 to 20:00, during which times most bird species are notably active, facilitating observations. The study employed a combination of the fixed-transect method, point-count method, and sound detection method for monitoring [22]. Transect designs were chosen in flat and open terrain, minimizing human disturbance and covering all landscape types. Three transects were established, with a total of 18 sampling points—6 points along each transect. The distance between each sampling point was greater than 200 m, and the sampling radius was set at 50 m. Transect 1 had a length of 1648 m; Transect 2 was 1492 m long, and Transect 3 was 1511 m long. All bird species present at the sampling points were recorded. Bird species were identified based on morphology, vocalizations, and behavior observed at the site. Additionally, photographic identification was used, and references such as “Complement of Zhejiang Bird Checklist in the Past Twenty Years” [34], A Checklist on the Classification and Distribution of the Birds of China (Third Edition) [35], and “On An Update of Recent New Bird Records in China” [36] were consulted to confirm bird species.

(2)

Determination of Avian Diversity

According to the 2022 animal resources survey in Haining City (http://lyj.zj.gov.cn/col/col1299187/index.html) (accessed on 3 November 2023) and A Checklist on the Classification and Distribution of the Birds of China (Third Edition) [35], concerning “Bird Diversity and Faunal Differentiation in Zhejiang Province” [37], the avian faunal type and migratory status in Haining City were determined. Avian dominant species were identified based on the proportion (P) of different population sizes to the total bird count: when P ≥ 10%, the bird species was established as dominant; when 1% ≤ P < 10%, the bird species was considered common; when 0.1% ≤ P < 1%, the bird species was classified as rare; in addition, when P < 0.1%, the bird species was categorized as uncommon [38].

Bird community diversity indices in different patch types were calculated based on the Shannon–Wiener index (H) and G-F index and analyzed in combination with patch area and number [22,26,27].

According to (1) Shannon–Wiener index (H):

$$H=-\sum _{y=1}^S{P}_y\ln P_y$$

(1)

where $P_y$ is specified to denote the proportion of the number of individuals of the $y$th species to the total number of individuals per sample line and $S$ is the number of species recorded per sample line. When the Shannon–Wiener index is higher, it indicates that there are more bird species in the sample plot, and the evenness of the distribution of bird individuals is higher.

According to (2)–(4) G-F index formula:

F index ($D_F$) for a region:

$$\begin{array}{ll}{D}_F& ={\displaystyle \sum _{k=1}^m}{D}_{Fk}\\ & \\ D_{Fk}& =-{\displaystyle \sum _{i=1}^n}{p}_i^{\mathrm{l}\mathrm{n}}{P}_i\end{array}$$

(2)

where $m$ is the number of families in the list of Aves, $n$ is the number of genera in the family, $p_i=s_{ki}/S_k$, $s_{ki}$ is the number of species in $k$ families and I genera in the list of Aves, and $S_k$ is the number of species in $k$ family in the list of Aves.

The G index ($D_G$) of a region:

$$D_G=-{\sum }_{j=1}^p{D}_{Gi}=-{\sum }_{j=1}^{p}q\mathrm{l}\mathrm{n}{q}_j$$

(3)

where p is the number of genera in Aves, $q_j=\frac{s_j}{s}$, $s_j$ is the number of species of genera in Aves, and $s$ is the number of species of Aves in the list.

$G-F$ index:

$$D_{G-F}=1-\frac{D_G}{D_F}$$

(4)

If all families in the Aves are monophyletic, i.e., when $D_F=0$, then the index $G-F$ for the region is zero, i.e., $D_{G-F}$ = 0.

2.2.2. Landscape Types

(1)

Landscape type research

Using GlobeLand30 (https://www.webmap.cn/commres.do?method=globeIndex) (accessed on 3 November 2023) as the base map data, preliminary image processing, such as geometric and radiometric corrections, was conducted using actual GPS points to enhance the map resolution [31,39]. The distribution of landscape types in the area was then illustrated using Photoshop 2020 software. Considering the ecological similarity in the utilization of the environment by birds, five landscape resources closely related to the birds were identified: forests, farmland, water bodies, villages, and bare rocks (Figure 3). Waterbody patches were categorized as natural water bodies, excavation- and irrigation-formed ponds and channels, and reservoir patches. The layout of landscape resources in the area forms a roughly circular distribution, with the outer ring comprising natural water bodies, farmland, villages, and factory patches, while the inner ring includes reservoirs, pond channels, and bare rocks. From the outer to inner ring, it can be summarized into several concentric layers: “Farmland Villages—Canal Harbors—Farmland Forests and Historical Sites—Industrial Areas—Secondary Vegetation—Bare Rock Outcrops—Reservoirs”.

(2)

Determination of landscape diversity

The site data were obtained through on-site surveying, drawn into CAD 2014, and imported into GIS 10.8. After operations such as correcting projection coordinates and converting features to polygons, the landscape data were exported. The obtained landscape data were then imported into the landscape index analysis software Fragstats 4.2 to calculate metrics such as the number of patches, patch area, the proportion of the largest patch to the landscape area, the proportion of the landscape area occupied by patches, and the average patch area. The relationship between habitat landscape pattern indices and bird diversity was calculated based on the data model. Data statistical analysis was performed using Excel 2020 and SPSS 26.0 to derive the results.

2.2.3. Relationship between Avian Diversity and Landscape Structure

A multiple linear regression model was established using SPSS 26.0 software to explore the relationship between avian diversity and landscape structure. The independent variables included various landscape patch indices, while the dependent variables were avian diversity index (H), family diversity index (F), genus diversity index (G), and G-F index.

In this context, B represents the regression coefficient, which quantifies the strength of the relationship between each independent variable and the dependent variable, also referred to as the slope. A positive regression coefficient indicates that the dependent variable increases with an increase in the respective independent variable, while a negative coefficient indicates a decrease. The larger the absolute value of the regression coefficient, the greater the impact (

Table 1. Multiple linear regression analysis.

	Unstandardized Coefficients		Standardized Coefficients
Model	B	Standard Error	Beta	t	p (Significance)
(Constant)	x	x	x	x	x
Independent Variable 1	x	x	x	x	x
Independent Variable 2	x	x	x	x	x

Dependent Variable: Dependent Variable 1.

).

Beta denotes the standardized regression coefficient, used to assess the relative importance of independent variables on the dependent variable. In comparison to B, Beta undergoes standardized processing, eliminating differences in units among independent variables. A positive Beta indicates a positive correlation between an increase in the independent variable and an increase in the dependent variable. Conversely, a negative Beta suggests a negative correlation, and when Beta is zero, the influence of the independent variable on the dependent variable can be considered negligible.

The t-statistic and p-value were employed to examine whether each independent variable significantly affects the dependent variable. A larger t-statistic and a smaller p-value indicate a more significant impact of the independent variable on the dependent variable. Typically, when the p-value is less than, the results are deemed statistically significant.

2.2.4. Bird Habitat Quality Assessment Methods

(1)

Bird Habitat Quality Assessment System

The habitat quality index reflects the suitability of habitat types for the main conservation objects in the natural reserve. According to the ‘Technical Specification for the Evaluation of Ecological and Environmental Conditions W020150326489785523925.pdf (mee.gov.cn) (accessed on 4 November 2023), the evaluation of bird habitats in the study area adopts the indicator system for natural reserve evaluation of aquatic wetland ecosystems (

Table 2. Indicator system for the evaluation of aquatic wetland ecosystem types in natural reserves.

	Weight (WI)	Landscape Structure Types	Sub-Weight (SWI)
Forest	0.18	Forest	0.25
		Shrubland	0.40
		Sparse Forest and Other Forests	0.35
Grassland	0.23	High-Coverage Grassland	0.60
		Medium-Coverage Grassland	0.30
		Low-Coverage Grassland	0.10
Aquatic Wetland	0.40	Rivers (Channels)	0.30
		Lakes (Channels)	0.30
		Tidal Flats	0.30
		Permanent Glaciers	0.10
Farmland	0.08	Paddy Fields	0.60
		Dryland	0.40
Construction Land	0.01	Urban Construction Land	0.30
		Rural Residential Areas	0.40
		Other Construction Land	0.30
Unused Land	0.10	Sandy Land	0.20
		Saline–Alkali Land	0.30
		Bare Soil	0.20
		Bare Rock Debris	0.20
		Other Unused Land	0.10

). In this evaluation system, the criteria layer is divided into bird habitat quality assessment, with the intermediate layer elements categorized into six evaluation criteria: forest, grassland, aquatic wetland, farmland, construction land, and unused land. The evaluation factors are designated as landscape structure types. The landscape structure types for forests include forests, shrublands, sparse forests, and other forests; for grasslands, they are high-coverage grassland, medium-coverage grassland, and low-coverage grassland; for aquatic wetlands, they are rivers (channels), lakes (channels), tidal flats, and permanent glaciers; for farmland, the landscape structure types are paddy fields and dryland; for unused land, they are sandy land, saline–alkali land, bare soil, bare rock debris, and other unused land, see

Table A1. Explanation of relevant evaluation factors.

Indicators	Landscape Structure Types	Definitions
Forest	Forest	Natural forests and artificial forests with a canopy closure greater than 0.20, including timber forests and protective forests, etc.
	Shrubland	Woodland with shrub coverage exceeding 0.30, including nationally designated shrubland and other shrublands.
	Sparse Forest	Sparse woodland with a canopy closure between 0.10 and 0.20.
	Other Forests	Other woodland types including afforested land, fallow land, nurseries, and various types of orchards (fruit orchards, mulberry orchards, tea gardens, and economic forests).
Grassland	High-Coverage Grassland	Natural grasslands, improved grasslands, and mowed grasslands with a coverage exceeding 50%, generally with good moisture conditions and dense grass cover.
	Medium-Coverage Grassland	Natural grasslands and improved grasslands with a coverage between 20% and 50%, usually with insufficient moisture and sparse grass cover.
	Low-Coverage Grassland	Natural grasslands with a coverage between 5% and 20%, characterized by a lack of moisture, sparse grass cover, and relatively poor conditions for livestock utilization.
Aquatic Wetland	Paddy Fields	Farmland with a guaranteed water supply and irrigation facilities, capable of normal irrigation in an average year, used for cultivating water-dependent crops such as rice and lotus.
	Dryland	Rain-fed farmland without irrigation water sources and facilities, relying on natural precipitation for crop growth. Dryland farmland with water sources and irrigation facilities capable of normal irrigation in an average year, mainly used for crops other than rice.
Farmland	Rivers (Channels)	Cropland primarily used for growing vegetables, rotational leisure, and fallow land.
	Lakes (Channels)	Area-shaped water bodies formed naturally or artificially, including natural lakes, rivers, artificial reservoirs, and ponds.
	Tidal Flats	Collective term for beaches, riverbanks, lake beaches, and swamps. Beaches refer to the tidal zone between high tide and low tide along the coast. Riverbanks and lake beaches refer to the land between the normal water level and the flood level of rivers and lakes. Swamps refer to flat, low-lying land with poor drainage, long-term humidity, seasonal or constant water accumulation, and the growth of wetland plants on the surface.
Construction Land	Urban Construction Land	Urban land for large, medium, and small cities, as well as built-up areas above the county and town levels. Unit: km2. Data source: Remote sensing monitoring.
	Rural Residential Areas	Rural settlement land.
	Other Construction Land	Land outside urban areas, including factories, large industrial zones, quarries, transportation routes, airports, and special-use land.
Unused Land	Sandy Land	Land covered by sand with vegetation coverage less than 5%, including deserts but excluding sandy beaches in water bodies.
	Saline–Alkali Land	Land with salt accumulation on the surface, sparse vegetation, and dominated by salt-tolerant plants.
	Bare Soil	Land covered by soil with vegetation coverage below 5%.
	Bare Rock Debris	Land covered by rocks or gravel with vegetation coverage less than 5%.
	Other Unused Land	Including high-altitude deserts, and deserts such as the Gobi.

for details. In the bird habitat quality evaluation system, forest land accounts for a weight of 0.18. When evaluating the quality of forest land, wooded areas contribute 0.25 to the forest land weight, shrub lands contribute 0.40, and sparse forest lands and other types of forest lands contribute 0.35. Grasslands hold a weight of 0.23 in the bird habitat quality evaluation system. When evaluating grassland quality, high-coverage grasslands account for 0.60 of the grassland weight, medium-coverage grasslands account for 0.30, and low-coverage grasslands account for 0.10. Aquatic wetlands have a weight of 0.40 in the bird habitat quality evaluation system. When assessing the quality of aquatic wetlands, rivers (channels) contribute 0.30 to the aquatic wetland weight, lakes (ponds) contribute 0.30, mudflat wetlands contribute 0.30, and permanent glaciers contribute 0.10. Similarly, the weights for arable land, built-up land, and unused land in the bird habitat quality evaluation system and the sub-weights for each structural type, can be derived.

(2)

Habitat Quality Index Calculation Method

According to the formula:

Habitat Quality Index = A_watn × (0.18 × Forest + 0.23 × Grassland + 0.40 × Aquatic Wetland + 0.08 × Farmland + 0.01 × Construction Land + 0.10 × Unused Land)/Total Area of the Reserve.

where A_watn—Normalization coefficient for the habitat quality index of aquatic wetland ecosystems in natural reserves, with a reference value of 785.6026.

Habitat quality assessment was conducted based on the grading standards for wetland ecosystem quality evaluation. When the normalized total evaluation score is ≥80, it is considered excellent; 80 > total score ≥ 60, good; 60 > total score ≥ 40, fair; 40 > total score ≥ 20, poor; and total score < 20 is considered very poor.

2.2.5. Development Disturbance Assessment Method

(1)

Development Disturbance Index System

Through planning measures and using the calculation method of the development disturbance index in accordance with the “Technical Specifications for Ecological and Environmental Condition Assessment W020150326489785523925.pdf (mee.gov.cn) (accessed on 5 November 2023)”, the construction outcomes of bird habitats were validated to assess the feasibility and potential for sustainable development of the research (

Table 3. Development disturbance weight.

Type	Urban Construction Land	Rural Residential Areas	Other Construction Land	Farmland
Weight (Wi)	0.40	0.10	0.40	0.10

and

Table 4. Functional Zone Weights.

Type	Core Zone	Buffer Zone	Experimental Zone
Weight (Wi)	0.60	0.30	0.10

).

(2)

Development Disturbance Assessment Index Calculation

Development Disturbance Index = Adev × (Functional Zone Weight × 0.40 × Urban Construction Land + Functional Zone Weight × 0.40 × Other Construction Land + Functional Zone Weight × 0.10 × Rural Residential Areas + Functional Zone Weight × 0.10 × Farmland)/Total Area of Protected Zones where Adev—Normalization coefficient for the Development Disturbance Index, with a reference value of 1520.3363830174.

According to the grading standards for habitat development disturbance assessment, when the normalized total score is ≥75, it is considered excellent, indicating effective protection of the native habitat of the main conservation target with no apparent traces of development disturbance. When 75 > total score ≥ 55, it is rated as good, indicating a good conservation status of the native habitat of the main conservation target, with some degree of development disturbance, but relatively mild. When 55 > total score ≥ 35, it is considered fair, indicating noticeable damage to the native habitat of the main conservation target with relatively obvious development disturbance. When 35 > total score ≥ 20, it is considered poor, suggesting partial loss of the native habitat of the main conservation target and severe development disturbance. When the total score is <20, it is rated as very poor, indicating a significant loss of the native habitat of the main conservation target with intense development disturbance.

3. Results

3.1. Bird Population Diversity Analysis

Observations reveal that the surveyed site hosts a total of 32 bird species from 11 orders and 13 families. Among them, there is only one species classified as a first-level protected animal, the Chinese Egret (Egretta eulophotes). Five species fall under the second-level protected category, including the Spot-billed Pelican (Pelecanus philippensis), Little Curlew (Numenius minutus), Mandarin Duck (Aix galericulata), Besra (Accipiter virgatus), and Crested Serpent Eagle (Ictinaetus malayensis). Some orders, such as Pelecaniformes, Charadriiformes, Carinatae, Falconiformes, Piciformes, Phasianidae, Columbidae, and Coraciiformes, are represented by a single family and species, accounting for 3.2%. Anseriformes comprises 11 species, constituting 35.4% of the total. Gaviiformes has two species, making up 6.4%, while Cuculiformes and Ciconiiformes each has two and three species, contributing 6.4% and 9.6%, respectively. Passeriformes includes seven species, representing 22.5%. Due to the stable growth trend of the Chinese Egret population in the Haining area of Zhejiang, it is considered a dominant species. The study area is mainly inhabited by Natatores and Passeres, followed by Grallatores, Terrestores, and Raptatores. Although there is a high concentration of individuals, there are relatively few dominant species, as many species only pass through without settling, such as the Black Kite (Milvus migrans) and Oriental Honey Buzzard (Pernis ptilorhynchus).

The 32 dominant bird species of the ecologically screened bird population in the Haining mines of Zhejiang are tabulated in

Table 5. Ecological populations of birds in Haining Mining Pit Park, Zhejiang, China.

Ecological Group	Typical Families	Typical Species	Species Number
Natatores	Anatidae, Pelecanidae, etc.	Pelecanus philippensis, Aix galericulata, Anas crecca, etc.	14
Grallatores	Ardeidae, Scolopacidae, etc.	Numenius minutus, Egretta eulophotes, etc.	4
Passeres	Bombycillidae	Bombycilla garrulus, Alauda arvensis, etc.	6
Scansores	Cuculidae, Picidae, etc.	Picus canus, Hierococcyx sparverioides, etc.	4
Raptors	Accipitridae, Ardeidae	Ictinaetus malayensis, Ardea alba.	2
Terrestores	Phasianidae, Columbidae	Phasianus colchicus, Streptopelia orientalis, etc.	2

. The study area is primarily dominated by Natatores and Passeres, followed by Scansores, Grallatores, and Terrestores. Fourteen species of Natatores are recorded, covering families such as Anatidae and Pelecanidae, with key representative species including the Spot-billed Pelican (Pelecanus philippensis), Mandarin Duck (Aix galericulata), and Mallard (Anas crecca). Four species of Grallatores are recorded, including families like Ardeidae and Scolopacidae, with representative species such as the Spoon-billed Sandpiper (Numenius minutus) and Yellow-billed Egret (Egretta eulophotes). Six species of Passeres are noted, encompassing families like Timaliidae and Alaudidae, with representative species including the Fairy Pitta (Bombycilla garrulus) and Skylark (Alauda arvensis). Four species of Scansores are recorded, including families like Cuculidae and Picidae, with representative species such as the Grey-headed Woodpecker (Picus canus) and Great Barbet (Hierococcyx sparverioides). Two species of Raptors are recorded, from the Accipitridae and Ardeidae families, represented by species like the Goshawk (Ictinaetus malayensis) and Great Egret (Ardea alba). Only two species of Terrestores are documented, which are the Phasianidae’s Ring-necked Pheasant (Phasianus colchicus) and the Columbidae’s Hill Pigeon (Streptopelia orientalis).

3.2. Analysis of Landscape Pattern Diversity

In the analysis of landscape diversity patterns, the selection of landscape indices such as the number of patches (NPs), patch area (CA), largest patch index (LPI), patch land cover proportion (PLAND), and mean patch area (AREA_MN) was made to investigate the structure of landscape patterns. Among these, the number of patches (NPs) represents the quantity of discrete habitats or land-use types within the landscape, providing an overall understanding of habitat diversity and complexity, which contributes to assessing the richness of the ecosystem. Patch area (CA) indicates the area of each discrete habitat or land-use type, helping to understand the size of different habitats and assess the contribution of various land uses to the ecosystem. The largest patch index (LPI) represents the relative size of the largest patch in the entire landscape, helping to identify dominant patch types in the landscape. Patch land cover proportion (PLAND) indicates the relative size of each patch in the entire landscape area, providing an assessment of the relative contribution of different patches to the landscape and aiding in the understanding of landscape structure. Mean patch area (AREA_MN) describes the average patch area in the entire landscape, offering an overall understanding of patch sizes within the landscape and assisting in evaluating the overall habitat structure of the landscape.

In the mining landscape of Haining, Zhejiang, the types of landscape patterns include natural water (8.31 ha, 5.95%), pit and ditches (1.11 ha, 0.79%), reservoirs (46.11 ha, 33.01%), forest land (8.55 ha, 6.12%), cropland (26.38 ha, 18.89%), shuttered plants (15.95 ha, 11.39%), villages (2.08 ha, 1.49%), and bare rocks (31.52 ha, 22.57%) (Table 2). Among these, reservoirs constitute the major area, with four reservoir patches, an average patch size of 11.53 ha, and accounting for 33.01% of the landscape patches. Although the reservoirs have poor connectivity, the patches are concentrated. Bare rock patches have relatively large areas, with the largest patch occupying 18.34% of the landscape area; however, their low vegetation cover negatively impacts bird diversity. The pit pond and ditch patches have the highest quantity (180), but the smallest average patch size (0.01 ha), indicating a dispersed landscape pattern. Villages and bare rock patches are relatively few, with one or two patches, respectively, scattered across different areas of the site. Overall, the surveyed area exhibits diverse landscape types, a scattered pattern, and a high degree of landscape fragmentation (

Table 6. Landscape pattern indices of different landscape types in Haining Mine Pit Park, Zhejiang, China.

Landscape Type	NP/Piece	CA/ha	LPI (%)	PLAND (%)	AREA_MN/hm2
Natural water	12	8.31	2.04	5.95	0.69
Pit and ditch	180	1.11	0.07	0.79	0.01
Reservoir	4	46.11	14.13	33.01	11.53
Forest land	19	8.55	1.65	6.12	0.45
Cropland	25	26.38	5.30	18.89	1.06
Shuttered plant	15	15.95	2.00	11.39	1.00
Village	1	2.08	1.49	1.49	2.08
Bare rock	2	31.52	18.34	22.57	15.76

).

3.3. Relationship between Bird Diversity and Landscape Patches

Through analysis, it was observed that among the existing landscape types, the reservoir patches have the largest total area and maximum patch area, with a recorded bird species from Order 3, Family 3, and Genus 11. Most of them are Natatores, and the bird diversity index (H) is 2.33; the family diversity (F) index is 0.81, and the genus diversity (G) index is 1.88. Although the area of ponds and channels is small, it recorded birds from four orders, seven families, and 10 genera, indicating a relatively good natural environment. The forested areas show the richest bird diversity (H = 2.83), covering Grallatores, Passeres, Scansores, and Raptors. A total of 10 orders, 16 families, and 20 genera are recorded, with family (F) and genus (G) diversity indices of 2.08 and 2.42, respectively. Shuttered plant and bare rock areas, due to strong human disturbance, suffer ecological damage, resulting in lower bird richness, with only resilient Passeres like skylarks (Alauda arvensis) and house martins (Delichon urbicum) being recorded (

Table 7. Bird diversity index of different landscape types.

Landscape Type	Section Number (F)	Genus Number (G)	Bird Diversity Index (H)	Section Diversity Index (F)	Genus Diversity Index (G)	G-F Index
Natural water	5	7	2.57	1.21	1.59	−0.31
Pit and ditch	4	7	2.27	1.32	1.88	−0.42
Reservoir	3	3	2.33	0.81	1.88	−1.82
Forest land	9	14	2.83	2.08	2.42	−0.01
Cropland	9	9	2.42	1.11	1.84	−0.66
Shuttered plant	8	11	2.23	1.80	1.88	−0.04
Village	6	7	2.05	0.69	1.88	−1.7
Bare rock	6	8	2.15	1.39	1.83	−0.32

).

The Avian Diversity Index (H), Family (F) Diversity Index, Genus (G) Diversity Index, and G-F Diversity Index were imported into the SPSS 26.0 software to predict the relationship between avian diversity and landscape structure. The independent variables included the number of patches, the patch area, the proportion of the largest patch to the landscape area, the proportion of patch area to the landscape area, and the average patch area for different landscape types. The dependent variables were the Avian Diversity Index (H), Family (F) Diversity Index, Genus (G) Diversity Index, and G-F Diversity Index. The results are presented below (

Table 8. Relationship between Avian Diversity (H) Index and Landscape Structure.

	Unstandardized Coefficients		Standardized Coefficients
Model	B	Standard Error	Beta	t	p (Significance)
(Constant)	2.378	0.222		10.722	0.002
Number of Patches	−0.001	0.002	−1.313	−0.246	0.822
CA	−0.003	−0.019	−1.181	−0.146	0.893
LPI	0.080	0.137	2.184	0.582	0.601
AREA_MN	−0.099	0.125	−2.413	−0.798	0.483

Dependent Variable: Avian Diversity Index (H).

,

Table 9. Relationship between Family (F) Diversity Index and Landscape Structure.

	Unstandardized Coefficients		Standardized Coefficients
Model	B	Standard Error	Beta	t	p (Significance)
(Constant)	1.405	0.471		2.983	0.058
Number of Patches	0.000	0.005	−0.018	−0.030	0.978
CA	−0.015	−0.019	−0.510	−0.364	0.740
LPI	0.106	0.292	1.540	0.362	0.741
AREA_MN	−0.106	0.265	−1.372	−0.400	0.716

Dependent Variable: Family (F) Diversity Index.

,

Table 10. Relationship between Genus (G) Diversity Index and Landscape Structure.

	Unstandardized Coefficients		Standardized Coefficients
Model	B	Standard Error	Beta	t	p (Significance)
(Constant)	1.945	0.244		7.975	0.004
Number of Patches	0.000	0.002	−0.066	−0.104	0.924
CA	−0.002	0.021	0.103	0.071	0.948
LPI	−0.021	0.151	−0.621	−0.140	0.898
AREA_MN	0.014	0.137	0.357	0.100	0.927

Dependent Variable: Genus (G) Diversity Index.

and

Table 11. Relationship between G-F Diversity Index and Landscape Structure.

	Unstandardized Coefficients		Standardized Coefficients
Model	B	Standard Error	Beta	t	p (Significance)
(Constant)	−5.30	0.602		−8.881	0.443
Number of Patches	0.001	0.006	0.093	0.184	0.866
CA	−0.054	0.053	−1.213	−1.032	0.378
LPI	0.407	0.373	3.897	1.091	0.355
AREA_MN	−0.370	0.338	−3.147	−1.093	0.354

Dependent Variable: G-F Diversity Index.

):

According to Table 8, the PLAND index was excluded from this model, indicating that the impact of the PLAND index on avian diversity is minimal. The Avian Diversity Index (H) has an inverse relationship with the number of landscape patches, CA, and AREA_MN. As the number of landscape patches, CA, and AREA_MN increase, the Avian Diversity Index (H) decreases, indicating a reduction in the richness of avian diversity. Notably, CA and AREA_MN significantly influence the Avian Diversity Index (H). The Avian Diversity Index (H) has a positive relationship with the LPI index; as the LPI index increases, the Avian Diversity Index (H) also increases, demonstrating a significant impact on avian diversity.

According to Table 9, the PLAND index was excluded from this model, indicating that the impact of the PLAND index on Family (F) Diversity Index is minimal. The Family (F) Diversity Index has an inverse relationship with CA and AREA_MN. As CA and AREA_MN increase, the Family (F) Diversity Index decreases, suggesting a reduction in the richness of bird families. Both CA and AREA_MN significantly influence the Avian Diversity Index (H). The Family (F) Diversity Index has a positive relationship with the LPI index; as the LPI index increases, the Family (F) Diversity Index also increases, demonstrating a significant impact on the diversity of bird families. There is no linear relationship between the number of patches and the Family (F) Diversity Index, but it significantly influences the Family (F) Diversity Index.

According to Table 10, the PLAND index was excluded from this model, indicating that the impact of the PLAND index on Genus (G) Diversity Index is minimal. The Genus (G) Diversity Index has an inverse relationship with CA and LPI. As CA and LPI increase, the Genus (G) Diversity Index decreases, suggesting a reduction in the richness of bird genera. Both CA and LPI significantly influence the Genus (G) Diversity Index. The Genus (G) Diversity Index has a positive relationship with AREA_MN; as the AREA_MN index increases, the Genus (G) Diversity Index also increases, demonstrating a significant impact on bird genus diversity. There is no linear relationship between the number of patches and the Genus (G) Diversity Index, but it significantly influences the Family (F) Diversity Index.

According to Table 11, the PLAND index was excluded from this model, indicating that the impact of the PLAND index on the G-F index is minimal. The G-F index has an inverse relationship with CA and AREA_MN. As CA and AREA_MN increase, the G-F index decreases, suggesting a reduction in the richness of bird species. Both CA and AREA_MN significantly influence the G-F index. The G-F index has a positive relationship with the number of patches and LPI; as the number of patches and LPI increase, the G-F index also increases, with the number of patches significantly impacting the G-F index of bird species.

The comprehensive multiple linear regression model reveals that avian diversity shows no significant relationship with PLAND. Avian diversity is significantly influenced by the number and size of patches, and there is a trend of decreasing avian diversity as the number of patches and patch size increase. It is evident that landscape fragmentation has a substantial impact on avian diversity, highlighting the importance of enhancing landscape connectivity in future planning.

3.4. Bird Habitat Quality Assessment

The assessment of bird habitat quality was conducted based on landscape patch identification and habitat quality index calculations. The result for the study area indicates a habitat quality index of 46.96 (

Table 12. Calculation of Habitat Quality Index.

Indicators	Landscape Structure Types	Area/ha	Weight	Calculation Result	Score	Result
Forest (0.18)	Forest	8.55	0.25	2.1375	0.38	46.96
Aquatic Wetland (0.40)	Rivers (Channels)	8.31	0.3	2.493	0.66
	Lakes (Channels)	46.11	0.3	13.833
	Tidal Flats	1.11	0.3	0.333
Farmland (0.08)	Paddy Fields	2.42	0.6	1.452	0.116
Construction Land (0.01)	Rural Residential Areas	2.68	0.4	1.072	0.59
	Other Construction Land	15.95	0.3	4.785
Unused Land (0.1)	Bare Soil	31.52	0.2	6.304	0.63

). The normalized evaluation result falls into the ‘Fair’ category, suggesting that the overall habitat quality is moderate. Therefore, measures need to be taken to optimize the ecological environment and achieve sustainable development in the construction of bird habitats.

4. Discussion

4.1. Current Issues

The analysis of the different landscape diversity and bird diversity indices shows that among the different landscape types, forestland has the highest bird diversity index, as this landscape patch has the highest number of plant species within it [1]. The water area is large, yet bird diversity is low, having been affected by ecological pollution left over from the original site. The low bird diversity in the village patches shows that anthropogenic disturbances have affected the habitat and reproduction of birds to some extent [12]. From the perspective of landscape patch diversity and bird diversity, the existing problems are summarized as follows:

4.1.1. Diverse Water Landscape with Poor Connectivity

The study area consists of natural water bodies, pond–ditch systems, and reservoirs, forming a water environment. Although the reservoir has the largest patch area, its bird diversity indices (science (F) and genus (G)) are lower compared to pond–ditch systems and natural water bodies. This could be attributed to ecological pollution within the reservoir, lack of plant communities, isolation from the water environment patches, high landscape fragmentation, and an inability to provide suitable habitats for certain water birds [13,14,15]. Pond–ditch systems, despite being artificially excavated with small patch areas, show high diversity due to the diverse surrounding landscape patches and rich vegetation [17,32]. Natural water bodies, with larger patch areas and strong connectivity, exhibit high ecological quality and diverse aquatic plant and fish species, providing abundant food resources and resulting in the highest bird diversity indices (H, F, and G) [24].

4.1.2. Heterogeneous Rocky Landscape and Habitat Degradation

Forested areas have the highest bird diversity indices (H, F, and G), possibly due to high environmental quality, well-developed vegetation, and a high rate of existing plant cover, offering hiding spots for birds. Due to mining activities, deforestation occurs, leading to habitat degradation and the emergence of a new landscape patch—rocky areas [40]. Rocky patches are concentrated in larger areas, recording only a few wading birds, indicating lower bird diversity. Extensive exposed land is unfavorable for bird concealment from humans, predators, and nesting activities. Birds tend to gather in mountainous areas with denser wetlands and forest resources [41].

4.1.3. Frequent Human Disturbances

Factories established due to mining activities are scattered throughout the site, becoming inactive after development. Villages are located next to the northern pit, close to forested and natural water body patches. Compared to villages, inactive factories show slightly higher bird diversity indices (H). In addition to landscape patterns, human disturbances also influence the distribution of bird diversity. In the absence of unified planning, human activities within the research area, such as vehicle traffic and factory operations, are inevitable. Weak awareness of bird protection leads to instances of bird hunting. Proximity to villages and roads results in fewer species of breeding and overwintering birds choosing this area. Frequent disturbances negatively impact bird diversity [12].

4.2. Restoration and Construction Strategies

Through a survey and analysis of the research area, existing issues in the study area were identified. In response to the problem of diverse aquatic landscape types but poor connectivity, a strategy was proposed to construct ecological floating islands to enhance patch connectivity. These floating islands were categorized into habitat-based and restoration-based floating islands based on their different restoration functions. In addressing the heterogeneity of bare rock landscapes and the degradation of bird habitats, a combined strategy of comprehensive restoration and partial restoration was suggested for ecological recovery. To tackle the issue of frequent human interference, an overall approach was proposed, including ecological protection and control zoning, overall landscape layout, and functional zoning. Additionally, local measures such as the construction of human and bird buffer zones and park road design were recommended to reduce human disturbance (Figure 4).

4.2.1. Establishing Ecological Floating Islands to Enhance Patch Connectivity

Due to water pollution and insufficient aquatic organisms like fish and shrimp for birds to feed on, rare bird species are not attracted to the area. By constructing ecological floating islands, the water can be purified, the aquatic plant coverage increased, and the water environment optimized [42,43,44,45]. These islands are set within the reservoir patch, providing a habitat for waterfowl and waders and serving as a medium to link the four reservoir patches, enhancing connectivity between patches and forming an ecological corridor.

(1)

Requirements for Ecological Floating Island Construction

The design of ecological floating islands should consider their functionality and how they are impacted by water flow speed, island area, curvature of island edges, distance from the land, bird population density, and island coverage [43,44,45] (

Table 13. Floating island construction requirements.

Type	Area/m2	Distance from Land/m	Edge Shape
Habitat-oriented floating island	1000–5000 m2	10 m	Irregular Edges
Restoration-oriented floating island	300–5000 m2	No limit	Regular Edges

).

Habitat-oriented floating islands primarily provide nesting sites for birds. The area of these islands should be controlled between 1000 and 5000 square meters, with curved edges and a distance from the land of at least 10 m [44,45].

Restoration-oriented floating islands are used to improve water body environments, with coverage accounting for over 30% of the water surface to effectively address the water pollution caused by mining [42]. These islands should also ensure suitable spaces for wading and waterfowl to take off and land. The purified water surface should constitute at least one-third of the total water surface. Individual restoration-oriented floating islands should have an area ranging from 300 to 2500 square meters, with regular edges [44,45].

(2)

Planting Scheme for Habitat-oriented Floating Islands

Habitat-oriented floating islands primarily serve as places for waterfowl to rest and play. Therefore, the selected plants on these islands must meet the physiological needs of waterfowl and not attract other species that may cause harm [44,46]. The matrix of habitat-oriented floating islands consists of water-filled float boxes, forming a structure with elevated centers and lower surrounding edges [42]. Around the perimeter of the floating island, we suggest choosing aquatic plants such as arrowhead (Sagittaria sagittifolia), wild rice (Zizania latifolia (Griseb.) Stapf), and lotus (Nelumbo SP) to provide habitats for birds and facilitate their foraging [47]. In transitional zones, we suggest opting for wetland herbaceous plants, including water celery (Apium graveolens), oriental knotweed (Polygonum orientale Linn), common reed (Phragmites australis), and umbrella plant (Phyllostachys heteroclite Oliver). Inside the floating island, we suggest selecting water-resistant shrubs and deciduous trees, we suggest planting Chinese cork oak (Quercus acutissima Carruth), burning bush (Euonymus maackii Rupr), golden rain tree (Koelreuteria paniculata), and Amur honeysuckle (Lonicera maackii) to provide hiding spots for birds [47]. The green area distribution for these three types of plants is 25%, 45%, and 30%, respectively [42,48] (Figure 5).

(3)

Planting Scheme for Restoration-Oriented Floating Island

According to the role of plants in supporting birds, their adaptability to the environment, and their impact on the surroundings, a selection of herbaceous wetland plants, aquatic plants, water-resistant shrubs, and deciduous trees was made [2,47,48,49]. Their roles for birds were categorized into providing food, concealment, and habitat; their adaptability to the environment was assessed in terms of cold resistance and water tolerance; and their environmental impact was considered in terms of nutrient control in water and counteracting water alkalization [46].

The matrix for the restoration-oriented floating island consists of a plant floating bed made of PE (polyethylene) material [42]. The primary function of this restoration-oriented floating island is to repair water quality and purify the water body. Therefore, the plants selected for the restoration-oriented floating island must be capable of absorbing harmful substances from the water [42]. The plant selection is divided into inner and outer circles. For the inner circle, species such as sweet flag (Acorus calamus L.) and bulrush (Scirpus validus Vahl) were chosen, constituting approximately 37% of the entire floating island, to improve water nutrient levels [42,48]. The outer circle includes plants like oriental cattail (Typha orientalis Presl) and nutgrass (Cyperus rotundus L.), also making up about 37% of the entire floating island, to mitigate water alkalization [42,48,49] (Figure 3).

4.2.2. Bird Habitat Restoration

(1)

Overall Restoration

Although the mining park has undergone short-term ecological succession, it still faces ecological issues, including geological damage residues, air pollution, ecological destruction, resource wastage, and water pollution [40,50]. The restoration of this site is divided into three steps [50]. After improving the overall ecological system of the mining park, specific efforts will be made to maintain the unique habitats that emerge during natural succession in the mining area, showcasing its distinct avian biodiversity.

The first step is to undertake engineering restoration [50]. First, level the land. Flatten steep slopes, deal with collapses and landslides, etc., to eliminate safety hazards and provide a stable land foundation for the construction of bird habitats [40]. Once the basic conditions are met, zeolite can be added to the soil. Zeolite, with its high porosity and surface area, can effectively adsorb and retain moisture and nutrients (such as nitrogen, potassium, and calcium) and improve soil aeration and permeability, aiding in the absorption of water and nutrients by plants [51]. After restoring the soil environment, plant local vegetation suitable for birds to inhabit and forage, including trees, shrubs, and herbs, which helps provide food sources and shelter for birds [52]. Next, restore the water environment. Connect the existing water systems for comprehensive use to form an overall cycle within the site, which can create lakes to improve the microclimate of the site [53]. Use ecosystems such as wetlands at the water outlet and inlet to protect and purify water quality. Manage the water quality of surrounding rivers by introducing nitrifying bacteria to participate in the nitrogen cycle in the water and decompose biotoxins [39]. Consider the relationship among rivers, mining pit lakes, and agricultural water use comprehensively, and at the same time, build a dam at the West Lake inlet to provide play areas for waterfowl and wading birds. Finally, optimize the structure of the habitat. Create or improve habitat structures for specific bird species according to their habits, such as bird nests, perches, and shallow water areas. Design bird-attracting devices to attract more birds to nest [25].

The second step involves ecological restoration. Firstly, reclaim the land used in the engineering restoration phase, repairing contaminated, degraded, or damaged land to reduce environmental risks, enhance the health and diversity of ecosystems, and improve soil quality [40]. Bioremediation measures can be implemented by planting hyperaccumulating plants to absorb and accumulate high concentrations of heavy metals in the soil, such as cadmium, lead, and copper [40]. Plants like mustard (Brassica juncea) and knotweed (Polygonum lapathifolium) can be used for soil bioremediation, while species like reeds (Phragmites australis), Miscanthus (Miscanthus floridulus), and oriental cattail (Typha orientalis Presl) can be employed for stabilizing the soil [40]. Secondly, habitat-type floating islands are established in the core experimental area for bird conservation to provide a suitable habitat for bird growth and development. Outside the bird conservation area, restoration-type floating islands can be established, and around these islands, plants like rrowhead (Sagittaria sagittifolia) and lotus (Nelumbo SP) can be grown, while snails and clams can be introduced to purify the water [48]. Concurrently, mechanisms for bird protection from natural predators are implemented, such as constructing complex nesting structures to safeguard the young birds and prohibiting bird hunting. These strategies are aimed at significantly increasing the bird population in the short term. Finally, post-restoration monitoring and control are essential, including the use of bird bands to monitor and manage the size and trends of bird populations, allowing for the estimation of population density, reproduction rates, and mortality rates [44].

The third step involves sustainable ecological development. Building upon the completed restoration of the overall ecological system in the mining area, efforts are made to preserve specific habitats that arise during natural succession, showcasing the unique avian biodiversity. This research area is envisioned to evolve into a habitat for birds [54].

(2)

Localized Restoration

The primary restoration method for the bare rock patches involves increasing green coverage to provide habitat for Grallatores, Passeres, and Scansores, each with distinct habitat requirements [33,55]. To address the degradation of bare rock patches, local slope adjustments and gradual slope reduction can be implemented. Fast-growing, adaptable, resilient, and locally well-suited native plants and pioneer plants can be chosen to offer foraging and nesting opportunities for birds (Table 4) [40,47,50]. For gallstones like Little Curlew (Numenius minutus) and Chinese Egret (Egretta sulfates) that prefer water-side habitats, water-resistant plants such as Dawn Redwood (Metasequoia glyptostroboides), Pond Cypress (Taxodium ascendens Brongn), and Bald Cypress (Taxodium distichum) with a height greater than 25 m can be selected to provide suitable environments for foraging and perching [3]. For Passeres such as Bohemian Waxwing (Bombycilla garrulus) and Skylark (Alauda arvensis), smaller plants like Black Locust (Robinia pseudoacacia) and Weeping Willow (Salix matsudana Koidz) with heights ranging from 5 to 25 m can be chosen to create habitats [2]. For Scansores such as the Grey-headed Woodpecker (Picus canus) and the Large Hawk-Cuckoo (Hierococcyx sparverioides), tall trees can be chosen with a height greater than 25 m, such as the large camphor tree (Cinnamomum camphora), Rose of Sharon (Hibiscus syriacus), and Cape Jasmine (Gardenia jasminoides Ellis), to provide them with concealed places. And Terrestores such as the ring-necked pheasant (Phasianus colchicus) and the mountain turtledove (Streptopelia) often prefer to forage in shrubs. It is suitable to choose low shrubs, such as the honeysuckle (Lonicera maackii), dwarf lilyturf (Ophiopogon japonicus), and iris (Iris tectorum), with a height of less than 1 m (

Table 14. Habitat-building vegetation selection for different ecological populations.

Ecological Group	Plant Selection	Plant Selection	Plant Height
Grallatores	Numenius minutus, Egretta eulophotes, etc.	Metasequoia glyptostroboides, Taxodium ascendens Brongn, Taxodium distichum, etc.	more than 25 m
Passeres	Bombycilla garrulus, Alauda arvensis, etc.	Robinia pseudoacacia, Salix matsudana Koidz, Cedrus deodara, Platycladus orientalis, etc.	5–25 m
Scansores	Picus canus, Hierococcyx sparverioides, etc.	Cinnamomum camphora, Hibiscus syriacus, Gardenia jasminoides Ellis, etc.	more than 25 m
Terrestores	Phasianus colchicus, Streptopelia	Lonicera maackii, Ophiopogon japonicus, Iris tectorum, etc.	Less than 1 m

).

4.2.3. Low Human Interference Design

(1)

Ecological protection control zoning

Habitat protection is a prerequisite for construction. Combined with the landscape pattern, and starting from improving the degree of bird diversity, the planning site is divided into an ecological core protection area and a human activity area [39,56]. Each sub-district puts forward control guidelines on spatial control and ecological protection. The ecological core protection zone comprehensively protects the diversity of birds, and the human activity zone opens up channels for human viewing of birds in a semi-open form. Among them, the ecological protection zone and public activity zone are the boundaries (Figure 6), with the human activity zone (about 60 ha) to the north and the bird core protection zone (about 81 ha) to the south.

(2)

General landscape layout and functional zoning

To coordinate the contradiction between urban development and bird diversity protection, the site is divided into a total of eight functional zoning areas (Figure 5), which are the ecological protection area, pit wall area, viewing area, common area, cultural village area, popular science museum area, health farming area, and ecological wet area to reduce human interference.

The ecological protection area covers an area of about 33 ha, which is divided into plant landscape areas around the East, West, and South lakes. To protect birds and maintain their habitats, the Eco-Reserve follows the concepts of low-impact and micro-renewal and preserves the original plant landscape of the site. No large-scale landscape nodes are designed within the ecological protection area, which follows its ecological succession.

The pit wall area of the mine pit covers an area of about 20 ha; the uneven surface of the mine pit is difficult to repair, and the rock wall area is close to the water area, which is very disturbing to the birds, so no node reconstruction will be carried out on the rock wall of the mine pit in the short term. When the bird habitat is completed and the ecosystem in the site is perfected, bird-watching trestles and other scenic programs can be introduced in the pit wall area of the pit to improve the ornamental value of birds.

The viewing area covers an area of about 5 ha, which is mainly divided by the viewing platform. The viewing platform is located at a high point with a good view around the water, which is convenient for observing the ecological floating island and is equipped with binoculars and corresponding explanatory signs for science popularization. The viewing platforms are of different forms: the viewing platform in Beijing is close to the forest and combined with a trestle; the viewing platform in Nankeng is combined with a sightseeing lane and a walking trail, making it a striking landscape box.

The common area covers an area of 23 ha, and the interior is an artificial plant landscape, adopting the way of plant landscaping to improve the ornamental landscape of the site, which is different from the ecological protection area. The plant landscape configuration in the public area not only satisfies the ornamental nature but also plays the role of attracting birds.

The cultural village area covers an area of 6 ha and is proposed to be transformed into a service-oriented village, where village houses are transformed into specialty lodgings, which can be especially combined with the living scenes of bird-raising farmers. After renovation, the cultural village area will be able to provide a variety of farming leisure experiences, including agricultural experience (planting and harvesting in home gardens), fishery experience (fishing in the forest), and folklore experience (lantern making).

The popular science museum area covers an area of 4 ha and mainly undertakes the function of science education, fully expressing the history of the habitat and the spirit of the place through the introduction and counting of the existing bird species on the site; the farmland landscape sequence partially preserves and organizes the current farmland to create a farming landscape; and the museum artistically reproduces the scenes of growth and breeding of birds. The science museum focuses on the process of local ecological evolution activities, animal and plant resources, and the physiological activities of popularized birds to raise people’s awareness of bird protection.

The health farming area covers an area of 2 ha. Combining with the current trend of urban agriculture, the farmland in the northern part of the site will be transformed into an urban vegetable garden, planting all-natural and additive-free vegetables, which will not only increase the economic income of the residents but also provide a source of food for the birds.

The ecological wet area covers an area of 48 ha as the internal water part of the study area; the North Lake is the ornamental medium for birds, and the South Lake is responsible for the function of purifying the site. To enhance the popularization of science and education of the attractions, a series of scientific explanation boards can be set up along the direction of the water flow, which provide a detailed explanation on the species of waterbirds, the composition of the wetland ecosystem, the construction of the ecological bird island, and the principle of water purification by plants.

(3)

Constructing buffer zones for people and birds

The buffer zone refers to the isolation distance between humans and birds, essentially a vegetation buffer strip [57,58,59]. The primary goal of setting up a buffer zone is to minimize external interference with bird activities. External disruptions encompass human activities, noise, lighting, and various other factors. Using the buffer zone as a boundary, no lighting systems are allowed within the buffer zone, and human access is strictly prohibited. The designated experimental area is the East Pit, chosen for its optimal lighting, topography, and existing vegetation conducive to bird growth and reproduction. The introduction of birds into the East Pit undergoes testing and verification, with the CAD-drawn buffer zone extending 60 m (as illustrated in Figure 7) [59]. Hence, isolating external factors within a 60 m range near the East Pit will not impact the growth and activities of the birds. As the ecological evolution progresses, birds within the experimental area will spread to the West Pit and South Pit. At that point, the buffer zone will expand to a 60 m area beyond the edges of the East, West, and South pits.

To create a vegetation isolation belt with trees below 3 m (approximating a 3.8° angle from a waterfowl’s perspective), we suggest selecting moisture-tolerant trees with well-branched structures as barriers. For upper-layer trees, we suggest choosing species like Zelkova schneideriana (Zelkova serrata), sycamore (Platanus acerifolia), and metasequoia (Metasequoia glyptostroboides) [57,58,59]. These trees will provide a barrier without obstructing the sightlines. For the mid-layer shrubs with heights ranging from 1 m to 1.5 m, we suggest selecting species such as Fatsia japonica (Fatsia japonica), hibiscus (Hibiscus syriacus Linn), Rhododendron simsii (Rhododendron simsii Planch), and (Serissa japonica). These shrubs should be regularly pruned to prevent them from obstructing the line of sight. Ground cover herbaceous plants in the isolation belt should include wetland species like Acorus gramineus (Acorus tatarinowii), daylily (Hemerocallis fulva), aster (Michaelmas daisy), and others. These plants will contribute to the overall ecological balance and enhance the habitat for waterfowl [2].

(4)

Garden path design

The park is designed with three levels of garden roads, controlling the interference distance (30–60 m) between bird habitats and garden roads [57]. The main road in the park connects to the city’s main road, with a width of 10 m and two lanes for two-way traffic. The first-level garden road, with a width of 8 m, transforms the carriageway into a one-way sightseeing lane and a walking path, reducing the disturbance of car noise on birds. The southern pit is designed with a second-level garden road, 6 m wide, exclusively for sightseeing vehicles. The third-level road is a walking path, 4 m wide, mainly connecting internal landscape nodes in the northern pit, while the third-level road in the southern pit leads to the ecological management station and is restricted to park staff only [60]. The garden roads not only ensure passage within the park but also, through grading, reduce the impact of human interference.

4.3. Post-Testing and Evaluation

4.3.1. Geographic Information Technology Detection

In the process of restoring the ecological park in the former mine, post-restoration monitoring is crucial. Relevant authorities can establish bird monitoring points within the park, combining transect and point count methods to detect bird activities. This involves recording the quantity and species of birds in the park, ensuring real-time protection against external disturbances. Bird monitoring points are planned in non-public areas, restricting access to the general public [56]. Leveraging geographic information technology, these points maximize their role in bird surveys, establishing a systematic bird protection mechanism. Implementing dynamic monitoring through modern technology not only safeguards birds but also provides data support for the restoration of bird habitats.

4.3.2. Development Disturbance Assessment

Based on post-planning zoning, the entire research site is divided into an ecological core protection zone and a human activity zone (experimental zone). The development disturbance assessment for the ecological core protection zone is based on the core zone weight. The ecological protection zone includes 33 ha of an ecological protection area, 12 ha of a quarry rock wall area, 32 ha of an ecological wetland area, and 4 ha of a scenic area, totaling 81 ha. According to the development disturbance weight calculation, the ecological protection area is classified as farmland, the quarry rock wall area and ecological wetland area are classified as other construction land, and the scenic area is classified as urban construction land. The result is 625.02, indicating that the bird’s native habitat in the ecological core protection zone is effectively protected with no apparent traces of development disturbance. The planning is feasible and sustainable.

For the human activity zone (experimental zone), the assessment is based on the experimental zone weight. It includes 8 ha of a quarry rock wall area, 16 ha of an ecological wetland area, 1 ha of a scenic area, 23 ha of a public activity area, 6 ha of a cultural village area, and 4 ha of a science museum area, totaling 60 ha. The public activity area and science museum area are classified as urban construction land, and the cultural village area is classified as rural residential areas. The result is 55.22, indicating that the conservation status of bird’s native habitat is good. Although there are some development disturbances, they are relatively mild. This suggests that introducing tourism projects while planning reasonably can effectively maintain the bird’s habitat to a large extent (Figure 8).

5. Conclusions

This study, taking the HaiNing quarry in Zhejiang as an example, proposes integrating the construction of bird habitats with landscape patterns. Based on the characteristics of the study area, the water and wetland ecosystems are used to evaluate bird habitats, obtaining evaluation results that indicate landscape ecological restoration is necessary before the site can become a bird habitat. In previous studies, there has been a lack of emphasis on evaluating the suitability of the habitat before constructing bird habitats, as seen in the work of Yan et al. [2]. Constructing bird habitats has often involved merely surveying the current status of the site and the number of birds, lacking a habitat evaluation system and data support, resulting in insufficient scientific rigor and a lack of theoretical support. In this paper, authoritative evaluation system indicators are used as the basis to conclude that the study area has the basic conditions and potential for constructing bird habitats. This guides the construction of bird habitats, and validation is carried out after planning and design, providing assurance for the sustainable development of bird habitats. In previous studies, the construction of bird habitats has predominantly relied on strategies, as exemplified by Xia et al. [52]. While some researchers have integrated bird habitats with landscape patterns, they have not proposed construction strategies from the perspective of landscape patterns, leaving the development of bird habitats confined to a theoretical realm. This paper bridges theory and practice by translating theoretical concepts into reality through the creation of site plans and landscape node designs.

In previous studies, landscape pattern data mostly originated from GIS (Geographic Information System), but due to limitations in precision, it was challenging to analyze smaller study objects accurately. For instance, as seen in the work of Xu et al. [61], they utilized a globally standardized plant community database and a 30 m resolution land-use/land-cover map to calculate landscape pattern indices. However, due to the high resolution of 30 m, a further reclassification was not feasible, and the scope of the study object was relatively large. In this paper, through on-site measurements and employing the support vector machine method, landscape patches were classified in a more refined manner, providing more accurate data. This approach enables quantitative research even for smaller areas and extends the horizontal scope of the study.

In this research, the combination of avian diversity and landscape pattern still has various shortcomings, such as errors in the regional bird quantity survey, leading to discrepancies with actual results [61]. However, the study of avian habitat construction needs to consider universality. The explicitly defined Avian Diversity Index and Landscape Pattern Index in the “dual indicators” are still the preferred references for avian habitat construction. Proposing strategies based on the relationship between avian diversity and landscape structure and adjusting them according to local conditions is still a fundamental process in territorial spatial planning. In the future, when conducting in-depth avian habitat construction, attention should be given not only to spatial differences but also to temporal differences, including variations in different seasons (such as focusing on the impact of spring and autumn on avian diversity over time). This enables the formulation of dynamic management for seasonal changes in avian habitat. Additionally, as landscape sustainability science gradually becomes a crucial theoretical foundation for habitat construction, future research can integrate landscape ecology, strengthen studies on the impact of landscape fragmentation on biodiversity, and delve into the influence of landscape patterns on avian habitat.

Research indicates that landscape patterns have a certain impact on bird diversity. Landscape planning strategies can be guided by landscape pattern indices to enrich bird diversity [25]. Through habitat restoration in the Haining Mine Ecological Park in Zhejiang, landscape enhancement projects such as ecological bird islands and human–bird buffer zones have been designed. These initiatives have an immediate effect on improving the environmental quality and landscape of the region. Although the primary goal is to create bird habitats, the ultimate objective is to enhance the richness of biodiversity in the area. After the ecological evolution of the site, both the quantity and diversity of organisms within the site have increased. This will play a regulating role in the local climate of Haining, Zhejiang, while also promoting regional economic development. However, both excessive development and conservation of bird habitats cannot achieve truly sustainable development. The key is to find a balance between human activities and bird habitats to achieve harmonious development between humans and birds [28].

6. Patents

Patent: ZL 2022 2 2846951.3 A kind of water surface cleaning device for ecological restoration.