Identification of Ecological Compensation Zones and Compensation Amounts: A Case Study of the Yellow River Delta

Abstract

Accurately identifying ecological compensation areas and scientifically determining appropriate compensation amounts are crucial for establishing a robust ecological compensation mechanism, which in turn is key to promoting the coordinated development of ecological protection and high-quality economic growth. This study innovatively proposes a framework for ecological compensation termed “Accounting of Ecosystem Services Value–Identification of Priorities for Payers and Recipients–Calculation of Ecological Compensation Amount (ESV–PPR–ECA)”. It utilizes the InVEST model and the emergy method to assess the value of ecosystem services, constructs the Ecosystem Payment and Recipient Priority Sequence (EPRPS) Model to identify the payers, recipients, and their priorities for ecological compensation, and employs the conversion factor method to calculate the Ecological Compensation Amount (ECA). This framework aims to address the questions of “How should compensation be provided?”, “Who should compensate whom?”, and “How much compensation is necessary?”, ensuring the optimal use of ecological compensation funds and providing a scientific basis for inter-regional ecological compensation. The study’s findings indicate that the total Ecological Compensation Amount for the Yellow River Delta in 2020 was 3.848 billion RMB, with the total amount receivable being 4.032 billion RMB and the total amount payable being 184 million RMB. The compensation funds should be prioritized for tideland and the Yellow River, and venture, cropland and industrial land should be the first to contribute compensation. Additionally, the Ecosystem Service Value of the Yellow River Delta showed a declining trend from 2015 to 2020, underscoring the urgent need to establish a horizontal compensation mechanism for the region. Such a mechanism would incentivize environmental protection and the construction of ecological civilization, ultimately enhancing ecosystem service functions. Therefore, we recommend the implementation of horizontal fiscal transfers, where financial assistance is provided from paying areas to recipient areas, offering a scientific reference for the establishment of a horizontal compensation mechanism within the Yellow River Delta.

1. Introduction

As the global population continues to grow and resource consumption increases, humanity faces escalating environmental challenges such as wetland shrinkage and water pollution [1,2,3]. Ecological compensation (EC) has emerged as a vital strategy for environmental protection worldwide [4], garnering widespread attention [5]. EC is founded on the principles of “beneficiaries compensate” and “polluters pay” [6]. Its core idea is to require beneficiaries or polluters to provide economic compensation to those who protect ecosystems. This approach internalizes the externalities associated with ecosystem service protection, thereby fostering greater awareness of environmental stewardship and promoting the harmonious development of economic activities and ecological conservation [7]. Since the launch of China’s reform and opening-up policy, the country has experienced rapid economic growth and a continuously expanding population, exacerbating environmental pollution and ecological degradation. In response to these severe challenges, the Chinese government has sought to balance ecological protection with economic development to achieve sustainable socioeconomic growth [8]. In 2020, China introduced the “Overall Plan for the Reform of the Ecological Civilization System,” which encourages the exploration of regional EC Schemes and mechanisms focused on local compensation [9]. This initiative aims to use EC as a tool to incentivize the maintenance and conservation of ecosystem services, offsetting the damages caused by economic development and thus ensuring both continued economic growth and environmental improvement. EC is crucial for resolving the pressing conflict between environmental protection and socioeconomic development [10].

The concept of EC was first introduced by Wunder of the Center for International Forestry Research (CIFOR) in 2005 in his work “Payments for Environmental Services: Some Nuts and Bolts” [11]. Between 2005 and 2015, the academic community engaged in extensive discussion and refinement of this concept. In 2015, Wunder authoritatively revised the definition of EC in his work “Revisiting the Concept of Payments for Environmental Services”, defining EC as a voluntary transaction between users and providers of ecosystem services [12]. This transaction involves payments for services that fall short of ecological value or subsidies for areas exceeding ecological value, ultimately manifesting as monetary compensation for ecosystem services. When the services provided by the ecosystem (such as water conservation, carbon storage, and crop production) do not meet their expected ecological value, individuals or businesses utilizing these services are required to pay a fee to compensate for the shortfall. Conversely, when certain areas of the ecosystem provide services that exceed their expected ecological value, governments or other organizations may offer financial subsidies to the managers of these areas to encourage them to continue maintaining and protecting these ecosystem services. China’s EC mechanism has evolved through several stages, from “polluters pay” to “protectors are compensated” and finally to “beneficiaries pay” [13]. Early EC efforts focused primarily on direct compensation for environmental damage [14]. However, as the understanding of the Ecosystem Services Value (ESV) deepened, the mechanism shifted toward emphasizing compensation for those who protect and maintain ecosystems [15]. Subsequently, the EC mechanism evolved into a “user-pays” model, wherein individuals or businesses that benefit from ecosystem services are required to pay fees to support ecosystem protection and restoration efforts [16]. Overall, EC has expanded from merely requiring payments from environmental destroyers to also subsidizing ecosystem service protectors, encompassing both the “beneficiaries pay” and “protectors are compensated” dimensions. In China, EC primarily relies on vertical transfer payments from central government funds. However, the limited coverage of these payments fails to address regional ecological protection issues effectively [17]. Therefore, there is a need to explore horizontal transfer payments from paying regions to recipient regions. Identifying EC-paying regions, recipient regions, and accurately calculating EC amounts are crucial for resolving regional ecological protection challenges. Especially in the context of limited EC funds, it is essential to prioritize recipient and paying regions appropriately to avoid misallocation of scarce resources, enhance the efficiency of fund utilization, and ensure that funds achieve maximum impact, thereby supporting sustainable regional development.

Current research on EC is becoming increasingly sophisticated. Various methods have been developed to calculate compensation amounts, including ecological protection costs [18], Willingness-to-Pay surveys [19], and ESV [20,21]. For instance, Pham et al. [18] proposed setting compensation standards based on ecological protection costs. Nyongesa et al. [19] conducted surveys and interviews to gauge residents’ willingness to pay for EC, providing valuable insights for the field. Niu [20] quantified ecological benefits using ESV and set compensation guidelines based on the results. He et al. [22] introduced a model for measuring spillover ecological value based on emergy analysis theory, offering new perspectives on EC. However, these methods have certain limitations. First, ecological protection costs do not necessarily equate to local ecological benefits [23,24], potentially undermining the effectiveness of compensation efforts [25]. Second, the WTP method relies on respondents’ understanding of the importance of environmental protection, making it difficult to align the interests of payers and beneficiaries [26]. Third, while ESV effectively captures regional differences in ecological benefits [27], relying solely on ESV can result in excessively high compensation amounts, straining government finances and stalling environmental protection projects [28]. In terms of identifying compensation areas, current approaches include the Payment for Ecosystem Services model (PES) [29], the Ecological Compensation Priority Sequence model (EERA) [30], and the Eco-economic Relative Advantage model (ECPS) [31]. For example, Jin et al. [29] used a PES model that integrates GDP with ecological capital to delineate payee and payer areas and quantify compensation amounts. Pengtian Jia [30] employed the EERA model to identify ecological payer, provider, and balance areas, while Xu et al. [32] applied the ECPS model to prioritize EC needs and allocate funds more effectively. Despite the ECPS model’s ability to rank spatial regions according to their need for EC, it cannot distinguish between payers and beneficiaries. Additionally, while the PES and EERA models can identify payee and payer areas, they do not account for compensation priorities, limiting their ability to optimize ecological and financial efficiency. To address the issue of high compensation amounts based solely on ESV, researchers have developed a conversion coefficient method [33] which integrates ESV and gross domestic product (GDP) as core indicators for calculating compensation amounts. This method allows for the coordinated allocation of compensation funds based on regional economic and ecological development, introducing a regional compensation intensity coefficient to reflect geographical differences in compensation needs, thereby enhancing the scientific accuracy of compensation calculations. However, research on prioritizing payer and beneficiary areas remains sparse. To fill this gap, this study proposes the Ecosystem Payment and Recipient Priority Sequence (EPRPS) model, which aims to accurately delineate compensation areas, identify “who should pay” and “who should receive”, and assess the urgency of compensation needs for both parties. The conversion coefficient method is then employed to scientifically quantify compensation amounts, optimizing the spatial allocation of compensation funds, improving both ecological and financial efficiency, and providing robust support for the development of a scientifically sound EC mechanism.

The Yellow River Delta is one of the most complete, typical, and youngest natural wetland ecosystems in the warm temperate zone, both in China and globally. It holds immense ecological and economic value. However, in recent years, unregulated human activities and rapid economic development have led to significant degradation of this ecosystem. The region now faces severe wetland shrinkage and intense resource utilization, resulting in prominent ecological and economic challenges. Therefore, it is urgently necessary to conduct EC assessments to identify the spatial areas of beneficiaries and payers, as well as their compensation priorities, to promote the harmonious development of ecological protection and high-quality economic growth. In this study, we focused on the Yellow River Delta as a case study and propose an “ESV-PPR-ECA” framework for EC research, aiming to achieve three main objectives. First, we evaluated ecosystem services based on land use types using the InVEST model and calculated the ESV using the emergy value method, quantifying the contributions of different ecosystem services and land use types to the Yellow River Delta. Second, we developed the EPRPS model to identify the spatial areas of ecological beneficiaries and payers, and to establish the priority order for compensation among these entities. Finally, we combined the ESV with the EC demand intensity coefficient to calculate the compensation amounts, determining the payment and receipt amounts for different land use types in the Yellow River Delta. This approach aimed to address the critical questions of “how to compensate,” “who compensates whom,” and “how much compensation is required,” thereby providing a theoretical foundation for local governments to explore horizontal transfer payments. The specific research process is illustrated in Figure 1.

2. Materials and Methods

2.1. Study Area Overview

The Yellow River Delta, located between Laizhou Bay and Bohai Bay, is one of the largest, youngest, and most biodiverse estuarine deltas in China. The study area is defined by a fan-shaped zone with Ninghai in Kenli County as its apex, extending from the Taoer River estuary in the north to the Xiaoqing River estuary in the south (118°01′01″–119°13′05″ E, 37°20′57″–38°12′18″ N) and encompassing five districts, Zhanhua, Hekou, Lijin, Dongying, and Kenli, covering a land area of approximately 5400 square kilometers (Figure 2). The average annual temperature, precipitation, and evaporation are 12.1 °C, 551.6 mm, and 1928.2 mm, respectively. The natural vegetation in the study area is primarily saline meadows, with sparse trees, and the main vegetation types include saline alkali herbs, tamarisk shrubs, reeds, and white grass. Additionally, the Yellow River Delta is rich in mineral resources, with large reserves of oil, geothermal water, rock salt, and coal, being the site of China’s second-largest oil field, the Shengli Oil Field. However, from 2015 to 2020, the region’s GDP decreased from 70.4 billion RMB to 62.8 billion RMB, reflecting an imbalance between ecological protection and economic development.

2.2. Data Preparation and Processing

2.2.1. Data Preparation

The data involved in this study for 2015 and 2020 include satellite remote sensing data, meteorological data, and socioeconomic statistical data (

Table 1. Data preparation and data sources.

	Data	Data Source	Resolution (m)
Meteorological Data	Annual Average Rainfall	NASA (https://www.nasa.gov/) (accessed on 27 June 2023)	30
	Potential Evapotranspiration	Based on meteorological station data, calculated using equation [34] $\begin{array}{l}E{T}_0=0.0013-0.48RA\times (T_{avg}+17.0)\\ \times {(TD-0.0123P)}^{0.76}\end{array}$	30
	Erosion Factor (R)	$R=0.053\times pr{e}^{1.6548}$	30
	Soil Erosion Factor (K)	Based on rainfall data	30
Satellite Remote Sensing Data	DEM	Geospatial Data Cloud (https://www.gscloud.cn/) (accessed on 10 July 2023)	30
	Slope Erosion Factor (LS)	Based on DEM calculation	30
	Landsat 5	GEE (2000-09-27)	30
	Landsat 8	GEE (2020-09-21)	30
	LUCC	Based on SVM interpretation	30
	NDVI	GEE	30
	Root Depth	Referencing the InVEST model’s root depth table, creating raster data using LUCC data	30
	GDP	Based on multi-factor weight distribution method	1000
	Available Water	Referencing the InVEST model’s water availability table, creating raster data using LUCC data	30
	Simpson’s Diversity Index	Calculated using FRAGSTATS4.2	30
Socioeconomic Data	Aquaculture Production	2015 and 2020 statistical yearbooks of Dongying and Binzhou	-
	Crop Production
	Tourism Income
	GDP

). Among them include ① meteorological data: rainfall data came from NASA’s official website; potential evapotranspiration data were calculated using the modified Hargreaves method; the rainfall erosion factor (R) and soil erosion factor (K) were based on rainfall data. ② Satellite remote sensing data: elevation data were sourced from the Geospatial Data Cloud; slope erosion factors were calculated based on the Digital Elevation Model (DEM); Landsat-5 and Landsat-8 remote sensing images, NDVI (Normalized Difference Vegetation Index), and FVC (Fractional Vegetation Cover) were downloaded from the Google Earth Engine platform (GEE); Land Use and Land Cover Change (LUCC) data were interpreted visually from Landsat remote sensing images using the Support Vector Machine (SVM) algorithm; root depth and available water data were based on LUCC data, referencing the InVEST model’s root depth and available water tables to create raster data; GDP raster data considered multiple factors closely related to human economic activities, such as land use types, nighttime light brightness, and population density, distributing GDP data based on administrative regions into raster units using a multi-factor weight distribution method. ③ Socioeconomic data: GDP data, tourism income, grain production, and aquaculture production in the Yellow River Delta region were obtained from the 2015 and 2020 statistical yearbooks of Dongying City and Binzhou City.

2.2.2. Land Use Type Interpretation

The Support Vector Machine (SVM) algorithm is characterized by high classification accuracy, fast processing speed, and stable performance in optimizing outliers and noise [35]. This study, based on the GEE platform and using Landsat remote sensing images as the base data, selected remote sensing images from the summer vegetation growth period with less than 5% cloud cover. Feature extraction was performed based on index features, topographic features, and spectral features, using SVM to interpret land use/cover maps for 2015 and 2020 (Figure 3), dividing the Yellow River Delta into 12 land use types: cropland, forest, Yellow River, water, grassland, settlement, tideland, salt pans, venture, industrial land, port, and saline (Figure 4). Additionally, field surveys were conducted to verify classification accuracy. The overall accuracy exceeded 88%, with a kappa coefficient greater than 0.86, meeting practical application requirements.

2.3. Selection of ESV Indicators

In the ESV assessment of the Yellow River Delta, we adopted the ecosystem service indicator system proposed by Ouyang Zhiyun and selected material supply services, regulation services, and cultural services as primary accounting indicators [36], considering the unique ecological structure and functions of the region. For material supply services, given the Yellow River Delta’s role as a major base for national grain production and fishery resources, we selected crop production and marine aquaculture as secondary indicators. For regulation services, considering the wetlands’ role in water conservation, carbon storage, soil retention, and water purification, we selected water conservation, carbon storage, soil retention, and water purification as secondary indicators. For cultural services, we included leisure contributions from natural landscapes like the Yellow River Estuary National Park as a secondary indicator. Notably, ecosystem support services provide the foundation and conditions for the realization of other ecosystem services, and their value can lead to double counting in ESV assessments, thus they are excluded from the constructed ecosystem service indicator system [37]. Overall, the ESV accounting framework was divided into three primary indicators and seven secondary indicators (

Table 2. Ecosystem Services Value accounting indicator system.

Primary Indicator	Secondary Indicator	Accounting Content	Indicator Description
Supply service	Crop production	Supply of crop crops and aquatic products.	The Yellow River Delta, as a major grain production base, significantly contributes to the local economy with its abundant fishery resources and thriving marine aquaculture
	Marine aquaculture
Regulation service	Carbon storage	Amount of carbon stored	Wetland vegetation plays an important role in carbon storage
	Water conservation	Amount of water conserved	The wetland ecosystem plays a key role in maintaining water balance
	Soil retention	Amount of soil retained	The root network of wetland vegetation contributes to preventing soil erosion
	Water purification	Amount of pollutants removed (nitrogen, phosphorus)	The ability of wetlands to absorb and degrade water pollutants
Cultural service	Leisure	Tourism income	Natural landscapes like the Yellow River Estuary National Park provide recreational spaces

). This framework comprehensively captured the key functions of the Yellow River Delta ecosystem and adhered to the principle of “adaptation to local conditions,” suitable for the accounting of ESV in the region.

2.4. Methods

2.4.1. Methods for ESV Accounting

The ESV is equal to the sum of the values of various individual indicators. The calculation method can be seen in Equation (1), while the value accounting methods for each individual indicator are detailed in

Table 3. Calculation methods for individual ecosystem service indicators.

Indicators	Material	Emergy	Value	Relevant Parameters
Crop Production	${\mathrm{Q}}_{\mathrm{C}\mathrm{P}}={\displaystyle \frac{\mathrm{N}\mathrm{D}\mathrm{V}{\mathrm{I}}_{\mathrm{i}}}{\mathrm{N}\mathrm{D}\mathrm{V}{\mathrm{I}}_{\mathrm{s}\mathrm{u}\mathrm{m}}(\mathrm{j},\mathrm{n})}}\times {\mathrm{G}}_{\mathrm{s}\mathrm{u}\mathrm{m}}(\mathrm{j},\mathrm{n})$	$E{m}_{cp}=Q_{cp}\times T_{cp}$	$V_{CP}={\displaystyle \frac{E{m}_{CP}}{EMR}}$	$Q_{cp}$ represents the material of crop production; $G_{sum}(j,n)$ is the total crop production of the j-th LULC type in the nth county; ${NDVI}_{sum}(j,n)$ stands for the cumulative NDVI value of the j-th LULC type in the n-th county; EmCP represents the emergy of crop production service; TCP represents the emergy transformity rate of crop production; VCP represents the value of the crop production service.
Marine Aquaculture	$Q_{MA}=G_{sum}(j,m)$	$\begin{array}{l}{Em}_{MA}=4186\times \mu \\ \times K\times Q_{MA}\times T_{MA}\end{array}$	$V_{MA}={\displaystyle \frac{E{m}_{MA}}{EMR}}$	$Q_{MA}$ represents the material of marine aquaculture; $G_{sum}(j,m)$ stands for total aquatic product yield of the j-th land use/cover type in the m-th district; TMA represents the emergy transformity rate of marine aquaculture; K is dry weight proportion coefficient, 1 kcal = 4186 J; μ is standard animal heat value, EmMA represents the emergy of marine aquaculture service; VMA represents the value of the marine aquaculture service.
Water Conservation	$Q_{wc}=(Y_{xj}-Runof{f}_{xj})\times S_j$ $Y_{xj}=(1-{\displaystyle \frac{AE{T}_{xj}}{P_x}})\times P_x$ $R\mathrm{un}of{f}_{xj}=P_x\times C$	$\begin{array}{l}E{m}_{wc}=Q_{wc}\times \rho \\ \times G\times T_{wc}\end{array}$	$V_{WC}={\displaystyle \frac{E{m}_{WC}}{EMR}}$	$Q_{WC}$ is the material of water conservation; $Y_{xj}$ represents the annual water conservation of grid x in the j-th type of ecosystem; ${AET}_{xj}$ and ${Runoff}_{xj}$ denote the annual actual evapotranspiration and surface runoff of grid x in the j-th type of ecosystem, respectively. $P_x$ represents the annual precipitation of grid x. C represents the surface runoff coefficient; Emwc represents the emergy of water conservation service; ρ represents the density of water (1.0 × 106 g/m3); G represents the Gibbs free energy (4.94 J/g); Twc represents the emergy transformity rate of water conservation; VWC stands for the value of the water conservation service.
Carbon Storage	$Q_{cs}={\displaystyle \sum _{i=1}^n(C_i\times S_i)}$$C_i=C_{i\_above}+C_{i\_below}+C_{i\_soil}+C_{i\_dead}$	$E{m}_{cs}=Q_{cs}\times T_{cs}$	$V_{CS}={\displaystyle \frac{E{m}_{CS}}{EMR}}$	$Q_{CS}$ represents the material of carbon storage service; $S_i$ represents the area of the i-th land use type; n represents the total number of LULC types in the study area; $C_i$,$C_{i\_above}$,$C_{i\_below}$,$C_{i_{soi}}$,$C_{i\_dead}$ represent the carbon density of the i-th land use type, aboveground biochar, underground biochar, soil organic carbon, and dead organic carbon, respectively. EmCS represents the emergy of carbon storage services; TCS is the emergy transformity rate of carbon storage; VCS stands for the value of the carbon storage service.
Soil Retention	$Q_{SR}=A_p-A_r$ $A_p=R\times K\times LS$ $A_r=R\times K\times LS\times C\times P$	$E{m}_{SR}=Q_{SR}\times T_{SR}$	$V_{SR}={\displaystyle \frac{E{m}_{SR}}{EMR}}$	$Q_{SR}$ represents the material of soil retention; $A_p$ represents the potential soil erosion quantity; $A_r$ represents the actual soil erosion quantity; R is the rainfall erosivity factor; K is the soil erodibility factor; LS denotes the slope length and steepness factor; C accounts for the vegetation cover and management factor; P signifies the soil retention practice factor; EmSR represents the emergy of soil retention service; $\mu$ is the emergy conversion ratio for the topsoil layer (6.78 × 102 J); TSR represents the emergy transformity rate of soil retention; VSR represents the value of the soil retention service.
Water Purification	${\mathrm{Q}}_{\mathrm{N}\mathrm{D}\mathrm{R}}=\mathrm{l}\mathrm{o}\mathrm{a}{\mathrm{d}}_{\mathrm{i}}-\exp \mathrm{o}\mathrm{r}{\mathrm{t}}_{\mathrm{i}}$	$E{m}_{NDR}=Q_{NDR}\times T_{NDR}$	$V_{NDR}={\displaystyle \frac{E{m}_{NDR}}{EMR}}$	${\mathrm{Q}}_{NDR}$ represents the material of water purification;${load}_i$ represents nitrogen load of the i-th grid; ${export}_i$ is nitrogen output of the i-th grid; EmNDR represents the emergy of water purification service; TNDR represents the emergy transformity rate of water purification; VNDR represents the value of the water purification service.
Leisure	${\mathrm{Q}}_{\mathrm{RC}}={\mathrm{S}}_{\mathrm{i}}\times {\displaystyle \frac{({\mathrm{SL}}_{\max }-{\mathrm{SL}}_{\mathrm{i}})}{({\mathrm{SL}}_{\max }-{\mathrm{SL}}_{\min })}}\times {\mathrm{SDI}}_{\mathrm{i}}$	$E{m}_{RC}=Q_{RC}\times T_{RC}$	$V_{RC}={\displaystyle \frac{E{m}_{RC}}{EMR}}$	$Q_{RC}$ represents the material of leisure; Si is tourism income of the i-th grid; SLi is slope of grid i; SLmax and SLmin represent the maximum and minimum slopes among all grids in the study area, respectively. Slope data generated from DEM; ${SDI}_i$ stands for Simpson’s Diversity Index of grid I; EmRC represents the emergy of leisure service; TRC represents the emergy transformity rate of leisure; VRC represents the value of the leisure service

. Firstly, the physical quantity of ecosystem services is assessed using land use data and the InVEST model; secondly, the emergy conversion rate is used to convert various ecosystem services into a unified solar emergy; and finally, the emergy–money ratio and regional GDP are used to account for the value of each service. Here, the emergy–money ratio (EMR) is calculated based on the emergy of the research area and GDP, as shown in Equation (2); the emergy conversion rate is referred to existing relevant studies in

Table 4. Emergy conversion rate parameter.

Indicatos	Emergy Conversion Rate	References
Crop production	1.51 × 1015 sej/t	[38]
Marine aquaculture	2.00 × 106 sej/g	[39]
Water conservation	4.09 × 104 sej/J	[40]
Carbon storage	3.78 × 107 sej/g	[39]
Water purification	2.80 × 109 sej/g	[40]
Soil retention	7.40 × 104 sej/J	[39]
Leisure	0.74 × 1012 sej/RMB	[39]

.

$$\mathrm{E}\mathrm{S}\mathrm{V}=V_{CP}+V_{AQ}+V_{WC}+V_{CS}+V_{SC}+V_{NRD}+V_{RC}$$

(1)

$$EMR={\displaystyle \frac{E{m}_T}{GDP}}$$

(2)

where ESV represents the ecosystem service value; Em_T is the total emergy of the ecosystem; EMR is the emergy-to-money ratio of the study region; GDP is the gross domestic product of the study region; V_CP stands for the value of crop production service; V_AQ stands for the value of marine aquaculture service; V_WC stands for the value of water conservation service; V_CS stands for the value of carbon storage service; V_SR stands for the value of soil retention service; V_NRD stands for the value of water purification service; V_RC stands for the value of leisure.

2.4.2. Methods for Ecological Compensation

In EC research, the results of ESV accounting can serve as theoretical upper limits for EC amounts. Given that the market values of agricultural and fishery products are already included in the regional GDP, the supply service value from the Yellow River Delta were not considered in the priority assessment and calculation of the Ecological Compensation Amount (ECA). Instead, only the non-market values of ecosystem service indicators within the region were utilized [41]. Accordingly, the Yellow River Delta focuses on five indicators—water conservation, soil retention, carbon storage, water purification, and leisure—for identifying EC priorities and determining compensation amounts.

(1)

EPRPS Model

ESV reflects the total value of products and services generated by natural ecosystems, focusing on “ecology”, while GDP refers to the value of all final products and services produced by regional economic activities in a given period, emphasizing “economics.” The EPRPS model constructed in this paper first clarified the supply–demand relationship between EC units by comparing the economic and ecological values across units, measuring the relative lag or lead development relationship between the two variables and consequently classifying EC-receiving areas and paying areas. Then, based on the ratio of non-market value of ecosystem services per unit area to GDP per unit area, it fully reflected the urgency of compensation in receiving and paying areas. The calculation methods are shown in Equations (3) and (4):

$$\mathrm{E}={\displaystyle \frac{{\mathrm{E}}_{\mathrm{S}\mathrm{V}\mathsf{\lambda }}}{{\mathrm{G}}_{\mathrm{D}\mathrm{P}\mathsf{\lambda }}}}$$

(3)

$$\mathrm{EPRPS}\{\begin{array}{l}\mathrm{ERPS}={\displaystyle \frac{{\mathrm{V}}_{\mathrm{N}}}{{\mathrm{G}}_{\mathrm{N}}}}\mathrm{E}>1\\ \mathrm{EPPS}={\displaystyle \frac{{\mathrm{V}}_{\mathrm{M}}}{{\mathrm{G}}_{\mathrm{M}}}}\mathrm{E}<1\end{array}$$

(4)

In Equations (3) and (4), E, Esv_λ, G_DPλ represent the EC Spatial Zone Index, which compares the ecological value and economic value of unit λ; if E is greater than 1, unit λ is classified as an EC Beneficiary. If E is less than 1, unit λ is considered an EC Contributor. $EPRPS$ stands for the EC Priority Sequence, encompassing both Ecosystem Payment Priority Sequence (EPPS) and Ecosystem Recipient Priority Sequence (ERPS), where EPPS denotes the priority for paying EC and ERPS indicates the priority for receiving it; V_N is the non-market value of ecosystem services per unit area within the compensation-receiving region; G_N is the GDP per unit area within the compensation-receiving region; V_M is the non-market value of ecosystem services per unit area within the compensation-paying region; G_M is the GDP per unit area within the compensation-paying region. A higher EPRPS value signifies a higher urgency for EC, while a lower value indicates a lower urgency.

(2)

ECA Accounting

In this study, the ECA was calculated using the conversion factor method [41], where the regional EC demand intensity coefficient was represented by the normalized results of EC priorities. The calculation equations are shown in Equations (5) and (6):

$$\mathrm{E}\mathrm{C}\mathrm{A}={\mathrm{V}}_{\mathrm{T}}\times \mathrm{k}\times \mathrm{t}$$

(5)

$$\mathrm{t}=2\times \arctan \mathrm{E}\mathrm{P}\mathrm{R}\mathrm{P}\mathrm{S}/\mathsf{\pi }$$

(6)

In Equations (5) and (6), ECA represents the regional Ecological Compensation Amount (RMB); V_T denotes the non-market value of the regional ecosystem (RMB); k is the ecological value conversion coefficient, which should reflect the current level of economic development in China and the ecological quality of the compensation area. Based on existing studies [42], this paper selected 15% as the EC conversion coefficient for the Yellow River Delta region; t stands for the intensity coefficient of regional EC demand. To avoid excessive concentration of ECA in a few counties or land types, the tangent function was introduced to normalize EPRPS.

3. Results

3.1. Yellow River Delta ESV Change Characteristics

The ESV in the Yellow River Delta showed a declining trend from 2015 to 2020, decreasing from 70.4 billion RMB to 62.6 billion RMB, representing a 10.96% reduction. When examining the various types of services (

Table 5. Value of different ecosystem service indicators from 2015 to 2020.

Service Value Classification			ESV (RMB)
	Primary Type	Secondary Type	2015	2020	Rate of Change
Market value	Supply service	Crop production	8.71 × 109	5.49 × 109	−36.94%
		Marine aquaculture	6.97 × 109	6.05 × 109	−13.17%
Non-market value	Regulation service	Water conservation	1.09 × 109	2.19 × 109	100.23%
		Soil retention	2.17 × 109	2.00 × 109	−7.73%
		Water purification	2.28 × 109	1.84 × 109	−19.22%
		Carbon storage	3.60 × 109	2.66 × 109	−26.22%
	Cultural service	Leisure	4.56 × 1010	4.25 × 1010	−6.85%
	Total		7.04 × 1010	6.27 × 1010	−10.96%

), cultural services experienced a decline, with their value dropping from 45.6 billion RMB to 42.5 billion RMB, a decrease of 6.85%. The value of provisioning services fell from 15.7 billion RMB to 11.5 billion RMB, with the value of food products and fishery products decreasing by 36.94% and 13.17%, respectively. The decline in the value of regulating services was relatively smaller, decreasing from 9.14 billion RMB to 8.69 billion RMB. Notably, however, the value of water conservation services bucked the trend and increased from 1.09 billion RMB to 2.19 billion RMB, marking a significant rise of 100.23%. In contrast, the values of soil retention, water purification, and carbon storage services all declined, with reductions of 7.73%, 19.22%, and 26.22%, respectively.

In terms of spatial changes, during the period from 2015 to 2020, the overall ESV in the Yellow River Delta exhibited a pattern where high-value areas were concentrated in the central and eastern regions, while low-value areas were sporadically distributed (Figure 5). The high-value areas were mainly located in the central part of the Yellow River Delta, including farmland, forestland, grasslands, and the eastern coastal wetland regions. These areas played a crucial role not only in maintaining regulating services such as soil retention and water conservation but also in providing provisioning services like food production. Particularly, the eastern coastal wetlands, which include nature reserves, national parks, and the Yellow River estuary, significantly enhanced the value of recreational services, thereby contributing to the overall increase in ESV. On the other hand, the low-value areas were sporadically distributed in the interior and northeastern parts of the Yellow River Delta. The interior regions were primarily areas with intensive human activities, such as urban residential zones, where large amounts of land have been converted for urban construction and agricultural use, leading to a decline in natural ecosystems and a subsequent reduction in ESV. The northeastern region, dominated by industrial land, particularly areas impacted by oil extraction and wetland reclamation, has seen significant alterations in hydrogeological conditions, resulting in lower ESV in these areas.

When analyzing the contribution of different land types to ESV, in 2015, the leading contributors were cultivated land (12.5 billion RMB), tidal flats (11.6 billion RMB), grasslands (11.3 billion RMB), and forest land (9.32 billion RMB). By 2020, the order of contribution shifted, with tidal flats contributing the most (11.8 billion RMB), followed by grasslands (10.1 billion RMB), forest land (9.47 billion RMB), cultivated land (8.38 billion RMB), water bodies (5.34 billion RMB), and saline–alkali land (3.52 billion RMB) (

Table 6. Ecosystem Service Value and proportion of different land use types from 2015 to 2020.

Land Use Type	ESV (RMB)		Proportion
	2015	2020	2015	2020
Cropland	1.25 × 1010	8.38 × 109	0.18	0.13
Forest	9.32 × 109	9.47 × 109	0.13	0.15
Grassland	1.13 × 1010	1.01 × 1010	0.16	0.16
Tideland	1.16 × 1010	1.18 × 1010	0.16	0.19
Yellow River	5.64 × 109	5.25 × 109	0.08	0.08
Water	5.68 × 109	5.34 × 109	0.08	0.09
Settlement	2.87 × 108	3.49 × 108	0.00	0.01
Saline	3.98 × 109	3.52 × 109	0.06	0.06
Industrial land	2.11 × 109	1.21 × 109	0.03	0.02
Salt pans	1.34 × 108	7.47 × 108	0.00	0.01
Venture	7.70 × 109	6.48 × 109	0.11	0.10
Port	9.74 × 107	8.03 × 107	0.00	0.00
Total	7.04 × 1010	6.27 × 1010	1	1

). The results indicate that between 2015 and 2020, the ESV of cultivated land and grasslands both showed a declining trend, with cultivated land experiencing the most significant drop of 33% and grasslands decreasing by 10.6%. In contrast, the ESV of tidal flats and forest land exhibited an upward trend, with increases of 1.7% and 1.6%, respectively (Figure 6). Notably, in 2015, cultivated land was the top contributor to ESV at 12.5 billion RMB, followed closely by tidal flats. However, by 2020, tidal flats had risen to the top position, becoming the most significant land type for providing ecosystem services, accounting for 19% of the total ESV. This shift suggests that recent local government efforts to protect tidal flat wetlands have enhanced their ESV.

3.2. EC Results for the Yellow River Delta

3.2.1. Identification of EC Zone

The spatial distribution of the EC areas is primarily concentrated along the eastern coastal zone, the central regions flanking the Yellow River, and the surrounding areas of the Yellow River’s old course in the north (Figure 7). These regions, characterized by wetlands, forests, and grasslands, play a crucial role in maintaining and enhancing ecosystem services, generating high-value ecological services, and significantly contributing to regional ecological security. In other words, these areas have sacrificed economic development opportunities to fulfill their ecological protection responsibilities, making the need for financial support through EC particularly urgent. Conversely, the EC payer areas are predominantly located in the central agricultural lands, coastal aquaculture zones, and the industrial areas in the northeast. These regions benefit from ecosystem services but also contribute to environmental degradation. Economic activities in these areas, including agriculture, fisheries, salt production, and oil extraction, are typically robust and may have negative impacts on the ecological environment. Therefore, it is their responsibility to financially compensate the areas providing or suffering from the loss of ecosystem services. This approach is essential to achieve a balance between sustainable regional development and the integration of ecological protection with economic growth.

3.2.2. Identification of Priority Zones for EC

To maximize the effectiveness of EC funds in promoting regional economic development and environmental protection, the implementation of EC schemes should be based on the compensation priorities of different land types. According to a 2020 study on the Yellow River Delta, we categorized these land types into Priority Payment Zones, Potential Payment Zones, Priority Recipient Compensation Zones, Secondary Priority Recipient Compensation Zones, and General Recipient Compensation Zones. In the Yellow River Delta, three land types fall within the Priority Recipient Compensation Zone (tideland, the Yellow River, and water), one land type is in the Secondary Priority Recipient Compensation Zone (saline), and two land types are in the General Recipient Compensation Zone (forests and grasslands). Additionally, three land types are classified under the Priority Payment Zone (cropland, industrial land, and port), and three land types are in the Potential Payment Zone (venture, settlement, salt pans). Priority recipient compensation provides higher ecological system service values and carry crucial ecological functions, such as water quality purification, water conservation, and carbon sequestration. Therefore, they should be prioritized for compensation to effectively protect their ecological functions. Secondary Priority Recipient Compensation and General Recipient Compensation Zones, although their ecological service values are relatively lower, still possess certain ecological functions and socioeconomic value. By comprehensively considering the ecological service values and socioeconomic development needs of various areas, effective resource allocation can be ensured. Priority payment areas (cropland, industrial land, port), due to their high-intensity economic activities, often exert significant pressure on the ecological environment, leading to a decline in ecological system service values. These areas need to balance economic development and ecological protection through the payment of ecological compensation. Potential payment areas (venture, settlement, salt pans) also require attention as they may impact the environment in future development.

Spatially, the Priority Recipient Compensation Zones are primarily located in coastal mudflat areas, along the Yellow River, and near water bodies. The Secondary Priority Recipient Compensation Zones are mainly concentrated in the northern regions and saline–alkali land near river mouths. The General Recipient Compensation Zones are predominantly found in the central-northern and central-southern forest and grassland regions. On the other hand, the Priority Payment Zones are concentrated in central farmland and northeastern industrial and port areas, while the Potential Payment Zones are distributed across northern and southeastern coastal aquaculture ponds, salt field reclamation areas, and inland residential zones within the Yellow River Delta (Figure 8). This analysis indicates that areas with higher compensation priority, such as wetland mudflats, hold significant ecological value and have the most urgent need for compensation to ensure their protection. Conversely, the northern industrial lands, ports, and central agricultural areas, characterized by a high-intensity economic development model often at the expense of the environment, have seen a decline in overall ESV. Due to the insufficient coupling of ecological and economic systems, these areas should be prioritized for funding to achieve EC and ensure the balanced development of both environmental protection and economic growth.

3.2.3. Accounting of ECA

The study results indicate that in 2020, the total ECA in the Yellow River Delta amounted to 3.848 billion RMB. Of this, the total compensation received was 4.032 billion RMB while the total payment made was 184 million RMB. Spatially, high ECA values were concentrated in the eastern and southeastern coastal areas of the study region, where tidal flats and grasslands dominate, contributing significantly to ecological value. In contrast, low compensation values were primarily distributed in the northeastern and central parts of the study area, particularly along the Yellow River and its old course, where arable land and industrial areas, which are heavily impacted by human activities and contribute less to ecological value despite higher economic development, are predominant (Figure 9).

From the perspective of land use types, the Yellow River Delta’s areas that require compensation payments include arable land, residential areas, salt pans, aquaculture ponds, industrial land, and ports. Among these, industrial land incurs the highest payment, amounting to 110 million RMB, making it a key focus of EC in the Yellow River Delta. Arable land follows, with a payment of 50 million RMB, while salt pans and aquaculture ponds have lower payment amounts, each not exceeding 10 million RMB. The compensation amounts for forest land, tidal flats, the Yellow River, water bodies, grasslands, and saline–alkali land are 743 million RMB, 1.5 billion RMB, 745 million RMB, 745 million RMB, 885 million RMB, and 410 million RMB, respectively. Notably, tidal flats account for the highest proportion of compensation among all land types at 54.18%, suggesting that tidal flats should be a primary focus in the EC process in the Yellow River Delta. Additionally, the compensation amounts for the Yellow River and water bodies, which constitute 17.25% and 16.37% of the total compensation, respectively, underscore their significant roles in the overall compensation for wetland ecosystem services. Conversely, the compensation for unused land is the lowest, representing only 0.04% of the total. Overall, the ranking of land use types in terms of compensation received in the Yellow River Delta is as follows: tidal flats (1.505 billion RMB), grasslands (885 million RMB), the Yellow River (745 million RMB), water bodies (744 million RMB), forest land (743 million RMB), and saline–alkali land (410 million RMB). In terms of compensation payments, the ranking is as follows: industrial land (110 million RMB), arable land (54 million RMB), salt pans (9 million RMB), ports (6 million RMB), residential areas (3 million RMB), and aquaculture ponds (2 million RMB).

4. Discussion

4.1. Analysis of the Key Stakeholders in EC

Adhering to the principle of “beneficiary pays and protector receives compensation”, it is essential to clearly define the parties involved in EC in the Yellow River Delta, as this is a prerequisite for implementing effective compensation mechanisms [43]. The providers of compensation are typically those who finance the compensation efforts, including both the entities that damage the environment and those who benefit from ecosystem services. The recipients of compensation are those who receive these funds, primarily individuals or regions that protect the ecosystem or suffer a loss of development opportunities due to the implementation of ecological restoration projects. These recipients typically include providers of ecosystem services and environmental protectors.

In the Yellow River Delta, the payers for EC include industrial land users, agricultural land users, and aquaculture operators. These areas not only benefit from ecosystem services but also contribute to environmental degradation. The key payers in this context are oil field companies, tourism sectors within the Yellow River Delta, fishermen, and farmers. The industrial oil fields in the delta are the largest developers and beneficiaries of the region’s ecological resources. The construction and daily operations of these oil fields release pollutants into the environment, leading to soil contamination and groundwater depletion and pollution, which gradually deteriorate the ecological environment. In recent years, the rapid development of tourism in the Yellow River Delta has attracted large numbers of visitors from across the country. The increasing number of tourists has exerted significant pressure on the local environment, making the tourism sector a key player in the EC process as both a developer and beneficiary of the delta’s natural resources. Additionally, fishermen and farmers, in pursuit of economic gains, often degrade wetland ecosystems, making them critical targets for EC. For instance, coastal fishermen frequently expand aquaculture ponds, leading to a reduction in wetland area and the degradation of wetland functions. Similarly, farmers use large quantities of pesticides and fertilizers in agricultural production, increasing nitrogen and phosphorus pollution. This pollution not only affects water quality but also poses long-term risks to the ecosystem. To ensure that farmers bear the external environmental costs of their production activities, it is necessary to establish a compensation mechanism that internalizes these costs.

The recipients of compensation in the Yellow River Delta include areas such as mudflats, grasslands, the Yellow River itself, reservoirs, and forested lands, which provide essential ecosystem services like water retention, carbon sequestration, and water purification. Key recipients are organizations and departments involved in protecting the Yellow River Delta’s environment, such as the Yellow River Estuary National Nature Reserve Management Bureau, the Yellow River Conservancy Commission, the Shandong Provincial Forestry and Grassland Bureau, the Dongying Natural Resources and Planning Bureau, and the Dongying Water Resources Bureau. These entities experience a certain degree of financial loss in the process of safeguarding the delta’s ecological environment. For example, the Yellow River Estuary National Nature Reserve Management Bureau restricts human activities within the reserve, leading to reduced tourism revenue, while the Yellow River Conservancy Commission invests substantial funds in water pollution control to maintain the quality of the Yellow River. Since these areas and the entities that hold the property rights to these natural resources experience financial losses as a result of their conservation efforts, they should be the focus of the EC initiative. Providing them with financial and policy support would encourage further engagement in environmental protection efforts.

Overall, the research on EC in the Yellow River Delta has clarified the roles of both the compensating entities and the recipients. It ensures that funds flow from regions benefiting economically to areas contributing to ecological protection. By collecting funds from areas benefiting economically and providing compensation to regions that bear the burden of ecological protection, this study aims to support those regions that sacrifice economic development for ecological responsibility [44]. This approach lays the groundwork for exploring horizontal transfer payments between regions [45,46].

4.2. Exploring EC Scheme for the Yellow River Delta

From 2015 to 2020, the value of ecosystem services in the Yellow River Delta exhibited a declining trend, underscoring the urgent need to establish mechanisms for horizontal transfer payments and market-based transactions. These mechanisms could stimulate broader societal involvement in environmental protection and ecological civilization construction, thereby enhancing ESV [47]. In federal countries such as the United States, Germany, and Mexico [48,49], horizontal transfer payments include fiscal equalization transfers between states and intergovernmental transfers within states, supported by well-established procedures for distribution between state-level and municipal governments. In contrast, China lacks a formalized horizontal fiscal transfer system, making such transfers between regions relatively uncommon [50].

To ensure the orderly advancement of horizontal EC in the Yellow River Delta, a coordination and management body will be established, led by officials from five district governments. This body will include representatives from the governments of Kenli County, Lijin County, Hekou District, Dongying District, and Zhanhua District, as well as from local fishing communities, farming households, tourism departments, oil field enterprises, the Yellow River Conservancy Commission, the Yellow River Delta National Nature Reserve Administration, forestry bureaus, and relevant experts. This diverse organizational structure aims to facilitate negotiations and decisions on EC, ensuring that payments are made equitably and sustainably. The compensation scheme prioritizes the collection of funds from oil field enterprises and farmers, followed by fishermen. In cases of limited funding, compensation will first be directed towards the Yellow River Delta National Nature Reserve Administration and the Yellow River Conservancy Commission to maximize efficiency. Overall, the horizontal fiscal transfer payments in the Yellow River Delta are guided by compensation policies established by the district governments. Under the supervision of the coordination and management body, fiscal assistance will be provided from paying areas to receiving areas (Figure 10), aiming to support horizontal transfer payments and achieve sustainable environmental development.

4.3. Comparative Analysis of Different ECA Accounting Methods

To compare with other methods for calculating ECA, this study employs the PES model to perform a comparative analysis. The results reveal that the total ECA for the Yellow River Delta is 4.42 billion RMB, with a total compensation of 17.53 billion RMB received and a total payment amount of 13.11 billion RMB. The compensation amounts for different land use types are as follows: grasslands (5.76 billion RMB), tidal flats (4.09 billion RMB), the Yellow River (2.57 billion RMB), saline–alkali lands (2.09 billion RMB), forests (1.46 billion RMB), and water bodies (1.36 billion RMB). The payment amounts for different land use types, from highest to lowest, are as follows: salt pans (3.69 billion RMB), residential areas (3.36 billion RMB), industrial land (2.82 billion RMB), aquaculture ponds (2.36 billion RMB), cropland (0.88 billion RMB), and ports (0.60 billion RMB) (Figure 11). Compared to results based on conversion coefficients, the PES model provides consistent delineations of compensation and payment zones, though the magnitude of compensation differs significantly. This discrepancy is primarily due to the following reasons: (1) both methods consider economic development GDP and ESV, leading to similar zone classifications; (2) the conversion coefficient method incorporates regional EC demand intensity coefficients, thereby better reflecting regional differences and actual ecosystem needs, enhancing the scientific validity and effectiveness of EC. In contrast, the PES model may not fully capture the actual needs of the Yellow River Delta’s ecosystem, leading to inaccurate compensation amounts that may not fully address the costs of ecological restoration and protection; (3) the densely populated Yellow River Delta may not be fully covered by the PES model, which is typically suited to areas with lower population density and higher natural resource ratios, where direct compensation to local residents serves as an incentive mechanism; (4) the Yellow River Delta’s economic activities, including agriculture and industry, are highly developed, with intense resource utilization, while the PES model is more suitable for areas with low resource use intensity and relatively good ecological conditions, focusing on compensating residents and protecting the environment. Overall, due to the ecological security threats caused by the lack of sediment supply from the Yellow River and the region’s high resource use intensity and urbanization rate, it is essential to quantify the ECA based on the regional EC demand intensity to reflect regional differences and actual ecosystem needs more accurately. Therefore, compared with the PES model, we argue that the conversion coefficient method is more suitable for calculating EC in the Yellow River Delta.

4.4. Limitations and Future Work of the Study

Although this study examines EC from the perspective of ESV, reflecting regional differences in ecological protection and economic development, several challenges remain. These include (1) complexity and valuation Issues: the complexity and non-market nature of ecosystem services mean that there is no unified standard for selecting their ecosystem service indicators, which results in non-comparable valuations across different studies. (2) Geographic Scope of Analysis: While this study calculates the ECA for different land types in the Yellow River Delta, it does not delve into the county level. This limits the ability to develop more precise compensation standards tailored to specific counties. Future research should focus on administrative units to ensure the effective implementation of EC mechanisms. (3) Methodological Variability: The ECA calculation methods used in this study—namely, the PES model and the conversion coefficient method—yield different results, and the InVEST model’s data processing is relatively complex, and due to the lack of meteorological information, only data from three meteorological stations in the study area are available. This variability highlights the need for further research using a range of methods and combining field surveys and questionnaires to understand local residents’ (particularly fishermen and farmers’) willingness and expectations for compensation. This will enhance the accuracy of compensation calculations and improve policy effectiveness. Furthermore, comprehensive assessments of all stakeholders’ interests are necessary to develop a fair and reasonable EC mechanism. This approach will help ensure the sustainable development of the ecological environment in the Yellow River Delta region.

5. Conclusions

This study evaluates ecosystem services based on land use types using the InVEST model and calculates the ESV using the emergy value method. Furthermore, an EPRPS model was developed to identify EC areas and assign compensation priorities among beneficiaries and payers. Lastly, the conversion coefficient method was used to estimate the ECA, clarifying the primary stakeholders and exploring compensation mechanisms for the Yellow River Delta. The key findings are as follows:

(1)

From 2015 to 2020, the ESV of the Yellow River Delta showed a declining trend, with coastal mudflats representing the highest ESV in 2020, accounting for 19% of the total service value. Among the different ecosystem service categories, cultural services had the highest value at 42.5 billion RMB. Spatially, the uneven distribution of ecological value intensified, with low-value areas expanding and high-value areas shifting eastward, indicating an urgent need to strengthen ecological protection.

(2)

The ESV and economic development levels showed positive and negative correlations with the EC priority, respectively. Coastal mudflats, the Yellow River, and water bodies were identified as the highest priority for EC due to their high ecological value and lower levels of economic development. These areas should be compensated first. Conversely, industrial land and farmland, which were identified as the highest priority for ecological payment, should bear the responsibility for funding EC to ensure the rational undertaking of ecological responsibilities. In 2020, the total ECA for the Yellow River Delta was 3.848 billion RMB, with 4.032 billion RMB allocated for beneficiaries and 1.84 billion RMB for payers. Industrial land was the primary payer, while coastal mudflats were the primary beneficiaries.

(3)

The Yellow River Delta should establish a horizontal fiscal transfer payment system where regions provide financial support to beneficiaries under the guidance of a coordinated management institution. Through adequate consultation, funds should be collected from ecological payers and distributed to ecological beneficiaries to ensure the efficient operation of the EC mechanism, thereby promoting sustainable ecological development in the Yellow River Delta.