Search Results (21)

Soil erosion has become an increasingly serious issue, drawing global attention. As one of the countries facing severe soil erosion in the world, China confronts significant ecological challenges. Against this backdrop, the country places great emphasis on soil conservation efforts, considering them a crucial component of ecological civilization construction. This study focuses on the carbon sink benefits of comprehensive soil conservation management in the loess hilly region and sandy slopes, using the Xiaonanshan Mountain small watershed in Youyu County, Shanxi Province, as a typical case for in-depth analysis. In terms of research methodology, an integrated monitoring approach combining fundamental data, measured data, and remote sensing data was developed. A comprehensive survey of the Xiaonanshan Mountain small watershed was conducted to categorize plant carbon pools and soil carbon pools, establish baseline scenarios, and utilize methods such as inverse distance spatial interpolation, sample calculation, and feature extraction to estimate forest carbon storage across different years and determine changes in soil and vegetation carbon storage. Simultaneously, data collection and preprocessing were carried out, including the gathering of fundamental data, field data collection, and internal data preprocessing. On this basis, a vegetation carbon storage model was constructed, and an assessment of soil carbon pool storage was conducted. The research results indicate that from 2002 to 2024, the continuous implementation of various soil conservation measures over 22 years has led to a significant increase in carbon storage within the Xiaonanshan Mountain small watershed. The vegetation carbon density of the entire small watershed increased from 14.66 t C/ha to 27.02 t C/ha, and the soil carbon density rose from 28.92 t C/ha to 32.48 t C/ha. The net carbon sink amount was 18,422.20 t C (corresponding to 67,548.08 t CO₂e in terms of carbon dioxide equivalent). Populus simonii and Pinus sylvestris var. mongholica significantly contribute to the carbon sink; however, due to partial degradation of Populus simonii, its net carbon sink amount is less than that of Pinus sylvestris var. mongholica. Additionally, the carbon sink capacity of the small watershed exhibits spatial differences influenced by conservation measures, with high carbon density areas primarily concentrated within the range of Populus simonii, while low carbon density areas are mainly found in shrub zones. The increase in carbon storage within the small watershed is primarily attributed to the contributions of vegetation and soil carbon storage, indicating that comprehensive soil erosion management has a significant carbon accumulation effect; moreover, the annual growth rate of vegetation carbon storage exceeds that of soil carbon storage, with the proportion of soil carbon storage increasing year by year. Furthermore, the vegetation carbon sink, soil carbon sink, and total carbon sink of the small watershed were separately calculated. In terms of benefit analysis, the Xiaonanshan Mountain small watershed offers ecological benefits such as increased forest coverage, carbon fixation and oxygen release, and biodiversity conservation; from an economic perspective, the value of carbon trading is substantial, promoting soil conservation and rural revitalization, with the total value of timber reaching 7.6 million yuan, of which the value of standing timber constitutes the largest proportion; social benefits include the improvement of environmental landscapes, stimulation of ecological tourism, and attraction of investment, with the Xiaonanshan Mountain Ecological Park receiving numerous visitors and generating significant tourism revenue. This research provides a theoretical basis and data foundation for comprehensive soil conservation management in project areas or small watersheds within the loess hilly and sandy slope regions, offering technical and methodological support for other soil conservation carbon sink projects in the area. Full article

An appropriate vegetation restoration pattern is crucial for maintaining and enhancing ecosystem functions and services in karst rocky desertification control areas. However, it is still unclear whether different vegetation restoration patterns will aggravate the trade-off of grassland ecosystem services in this area. This study focuses on grassland ecosystems in the karst desertification control area, comparing artificial restoration measures (Dactylis glomerata single-species sowing grassland, DG; Lolium perenne single-species sowing grassland, LP; Lolium perenne + Trifolium repens mixed-species sowing grassland, LT) with natural restoration measures (NG). Seven ecosystem services (forage yield, soil retention, soil water conservation, carbon fixation and release, soil carbon storage, soil nutrient retention, and biodiversity conservation) as well as total ecosystem services were quantified using field monitoring data. The relationships between these services were evaluated through Spearman correlation analysis. The results showed that different vegetation restoration patterns significantly influenced the provisioning, regulating, and supporting services of the grassland ecosystem (p < 0.001). Three types of relationships were observed (trade-off, synergy, and neutral), but the trade-off relationship was not significant (p > 0.05). The total ecosystem service of LT (0.79) was significantly higher than that of NG (0.21), DG (0.36), and LP (0.41), with a significant synergy observed between soil nutrient conservation, forage yield, and carbon sequestration and oxygen release (p < 0.05). Therefore, LT is considered the best vegetation restoration practice for the karst rocky desertification control area compared with other patterns. This study provides theoretical guidance for vegetation restoration in degraded karst ecosystems. Full article

In view of global climate and environmental challenges, exploring sustainable urban vegetation management and development is crucial. This study aims to investigate the design strategies of urban road green space plants under the guidance of the dual theories of carbon sequestration and cooling eco-efficiency and aesthetics. In this study, Yangling, a representative small- and medium-sized city, was selected as the study area, and road green space plants were identified as the research objects. The assimilation method was employed to ascertain the carbon sequestration and oxygen release, as well as the cooling and humidification capacities of the plants. The aesthetic quality of the plants was evaluated using the Scenic Beauty Estimation and Landscape Character Assessment. Finally, we propose design strategies for landscapes with higher aesthetic and carbon sequestration and cooling benefits. The results demonstrate a clear nonlinear positive correlation. The carbon sequestration and cooling benefits of plants and the aesthetic quality, with correlation coefficients of 0.864 and 0.922, respectively. Across the same sample points, the rankings of standardized values for carbon sequestration, cooling benefits, and aesthetic quality vary minimally. This indicates that eco-efficient plants with harmonious colors and elegant forms can boost the aesthetic appeal and ecological function in road green spaces. Furthermore, the Sophora japonica Linn., Ligustrum lucidum Ait., Koelreuteria paniculata Laxm., Prunus serrulata Lindl., Prunus cerasifera Ehrhar f., Ligustrum sinense Lour., Photinia × fraseri Dress, Ligustrum × vicaryi Rehder, Sabina chinensis (L.) Ant. cv. Kaizuca, and Ophiopogon japonicus (L. f.) Ker Gawl. are proved to be ecologically dominant plants. They can be employed as the principal selected species for plant design. This study summarizes applicable design strategies for three types of green spaces: avenue greenbelts, traffic separation zones, and roadside greenbelts. The nonlinear regression model developed here provides a reference for scientifically assessing and optimizing urban planting designs. Full article

In this paper, a novel process for synergistic carbon in situ capture and the utilization of blast furnace gas is proposed to produce CO via chemical looping. Through thermodynamic analysis, this process was studied in terms of the carbon fixation rate, CO yield, in situ CO₂ utilization rate, CH₄ conversion rate and energy consumption. It provides valuable insights for achieving efficient CO₂ capture and in situ conversion. FeO and CaO are used as the oxygen carrier and the carbon carrier, respectively. Under the conditions of reaction temperature of 400 °C, pressure of 1 bar and FeO/CO ratio of 1, the carbon capture rate of blast furnace gas can reach more than 99%. In the carbon release reactor, the CO yield is lower than that in the original blast furnace gas (BFG) if no reduction gas is involved. Therefore, methane is introduced as a reducing gas to increase CO yield. When the reaction temperature is increased to 1000 °C, the pressure level is reduced to 0.01 bar and the CH₄/C ratio is 1:1 (methane to carbon), the CO yield is four times that of the initial blast furnace gas. Under the optimal conditions, the energy consumption of the system is 0.2 MJ/kg, which is much lower than that of the traditional process. This paper verifies the feasibility of the new process from the perspective of thermodynamics. Full article

As a technology for water landscape performance that considers landscape, ecological, and social effects, nature-based solutions play a crucial role in enhancing the functionality of integrated ecosystem services on the micro-scale. This study conducted a systematic investigation into the landscape performance of the “Clear as a Drain” composite sponge facility at Handan Garden Expo Park. The following conclusions were drawn: (1) In terms of ecological restoration support services, the “Clear as a Drain” artificial wetland exhibited diverse habitat types, a rich variety of plant species specific to the site’s region, and high plant diversity indices for shrubs (1.776) and herbaceous aquatic plants (3.352). Reclaimed water reused in the artificial terraced wetland promoted plant growth and diversity while contributing to site self-rehabilitation; plants also significantly contributed to carbon fixation, oxygen release, and carbon emission reduction. (2) Regarding ecological restoration regulation services, the artificial wetland effectively purified reclaimed water with substantial improvements observed in incoming water quality during spring, summer, and autumn—particularly notable purification effects were observed during the summer months. Pollutant reduction rates for COD, BOD₅ ammonia nitrogen, TP, and TN reached 75.8%, 72.1%, 93.8%, 96.7%, and 90.3%, respectively; different independent subsystems within the wetland demonstrated distinct advantages in pollutant removal; park plants displayed strong air purification capabilities; annual energy savings from park plants could fully cover daily energy consumption for nearby residents. This case could serve as guidance for scientific management and design parameter optimization of other composite sponge facilities. Full article

In order to explore the carbon fixation and oxygen release capabilities of riparian plants in Wuhan, the photosynthetic rate (Pn) and morphological indicators of 13 typical riparian plants in the middle section of the Xunsi River in Wuhan were measured by portable photosynthesis apparatus. The daily carbon fixation and oxygen release of each plant at different scales were calculated, and the carbon fixation and oxygen release capacity and its influencing factors were analyzed. The results show that: (1) according to the biological characteristics, the daily carbon fixation and oxygen release capacity per unit leaf area was higher in herbaceous than in trees; the daily carbon fixation and oxygen release capacity per plant, per projected area, and per land area were higher in trees than in herbaceous. (2) The plant with the strongest ability of daily carbon fixation and oxygen release per unit leaf area was Ruellia brittoniana, and the weakest was Triadica sebifera; the plant with the strongest ability of daily carbon fixation and oxygen release of a single plant was Metasequoia glyptostroboides, and the weakest was Lolium perenne; the plant with the strongest ability of daily carbon fixation and oxygen release per land area was Metasequoia glyptostroboides, and the weakest was Alternanthera sessilis. (3) The carbon fixation and oxygen release ability of 13 plant species was analyzed by cluster analysis based on per unit leaf area, per plant, and per land area; ten species of herbaceous plant could be divided into three grades and three species of trees into two grades. This study provides a theoretical reference for the selection and application of riparian zone vegetation in Wuhan, and provides a scientific basis for the evaluation of riparian zone ecological benefits. Full article

The Three-North Shelterbelt Project is the largest ecological engineering initiative in China to date, distinguished by its immense scale, extended construction period, and widespread benefits for the population. The gross ecosystem product (GEP) serves as a crucial indicator for assessing ecological benefits. This study focuses on the Three Northern Protection Forest Project Area, utilizing GEP calculations for the years 2000 to 2020. This study evaluates variations in the production values of different ecosystem services to reflect the ecological conservation benefits of the restoration project. Additionally, it analyzes the spatiotemporal evolution and trends of the GEP calculations, offering data references and decision support for the enduring efficacy of ecological restoration projects. The findings are as follows. (i) Between 2000 and 2020, the GEP of the Three-North region exhibited significant growth with continuous enhancement of various ecosystem service functions; the most substantial rate of change was observed in the water conservation function, followed by carbon sequestration and oxygen release, soil retention, windbreak and sand fixation, flood regulation, and environmental purification functions. (ii) The per-unit area value of different ecosystem types generally increased; the forest ecosystem displayed the largest growth rate at 61.18%, followed by shrubland ecosystems at 49.84%. (iii) The spatial distribution of ecosystem service in the Three-North region displayed a clustering trend alongside notable spatial heterogeneity. High-high clustering zones were identified in areas such as the Tianshan Mountains, Altai Mountains, Qilian Mountains, and Greater and Lesser Khingan Mountains. Conversely, low-low clustering areas were scattered, forming patchy distributions in regions like the Tarim Basin, northern Qinghai-Tibet Plateau, and the Hexi Corridor. This study, by analyzing the gross ecosystem product of the Three-North Shelterbelt Project region, unveils the spatial distribution characteristics, trends, and variations in ecosystem service values over the past two decades. It provides data support and decision guidance for the long-term efficacy of future ecological conservation and restoration projects. This study incorporates the GEP accounting method into the assessment of the effectiveness of major conservation projects. Compared to the traditional methods of effectiveness assessment, this represents a significant exploration and innovation. Full article

Analyzing human–environment coupling is important in understanding the mechanisms and developments of human–environment systems. However, the current frameworks and approaches evaluating the relationship between human activities and the ecological environment remain limited. Integrating the vegetation-impervious surface–soil–air framework, Mann–Kendall test, correlation analysis, two-step floating catchment area method, coupling analysis, and optimal parameters-based geographical detector, this study comprehensively evaluate the environmental changes and analyzes the coupling relationship between environment and human activities, mainly in terms of habitat quality, landscape pattern, and ecological services. The study area was the Qilian Mountain National Nature Reserve in Gansu province, China, an ecologically fragile region with an environment closely linked to human activities. Along with district and county census data, various remote-sensing products (e.g., MODIS, Landsat) were used to assess the ecological level and human–environment coupling state of the study site from 2003 to 2019. The main results show: (1) The remote sensing composite index, which integrates eight ecological sub-indices, effectively captures the spatial and temporal variations of the ecological environment in the study area, providing comprehensive and detailed environmental information. (2) Analysis using the Mann–Kendall-correlation classification, coupling degree, and two-step floating catchment area methods consistently demonstrates a gradual coordination between human activities and the ecological environment in the study area. (3) In comparison to spatially interpolated population data, the remote sensing human activity index more significantly represents the spatial impact of human activities on the ecological environment. (4) The environmental aspects most strongly associated with human activities include carbon fixation and oxygen release, vegetation, humidity, and soil. (5) The ecological environment level does not uniformly deteriorate with increasing population density, and a notable alignment is observed between changes in the ecological environment and the implementation of government environmental protection policies. Full article

Since 2007, Ulva prolifera, a green macroalgal species that blooms periodically in the Yellow Sea of China, has caused the world’s biggest green tide, which induced harmful ecological impacts and economic losses. When the alga is subject to prolonged exposure to air, it suffers abiotic stresses. To explore the physiological and molecular mechanisms of salt stress, the transcriptome data of U. prolifera at different salinities (30, 50, and 90 psu) were obtained by high-throughput sequencing using the Illumina HiSeq platform, and photosynthetic physiological parameters were also measured. The results showed that a total of 89,626 unigenes were obtained after de novo assembly, of which 60,441 unigenes were annotated in the databases (NR, NT, KO, SWISS-PROT, PFAM, GO, and KOG). GO functional enrichment analysis revealed that the enrichment of differentially expressed genes (DEGs) was mainly in cellular, cell, and binding processes. KEGG metabolic pathway enrichment analysis showed that the most frequently enriched pathways of DEGs included glycolysis, pyruvate metabolism, peroxisome, and fatty acid biosynthesis. In addition, resistance-associated proteins, such as heat-shock proteins, microtubule-associated proteins, ubiquitin-associated proteins, abscisic-acid-signaling-pathway-associated proteins, and antioxidant-related proteins are upregulated under salt stress. Genes associated with photosynthesis and carbon fixation pathways are also upregulated, accompanied by an increase in photosynthetic oxygen release rates. These findings provide a basis for understanding the molecular mechanisms of the response of U. prolifera to salinity change, thus providing a theoretical basis for the analysis of the green tide outbreak mechanism. Full article

Freshwater components in the Southern Ocean, whether sea ice meltwater or meteoric water, influence the growth of phytoplankton by affecting water stability and supplying dissolved iron (DFe). In addition, melting sea ice stimulates phytoplankton blooms by providing ice algae. In this study, sea ice meltwater and meteoric water in the Amundsen Sea (AS) were differentiated by their stable oxygen isotopic compositions (δ¹⁸O), while the phytoplankton carbon fixation rate (CFR) and iron uptake rate (FeUR) values were determined using the ¹⁴C and ⁵⁵Fe tracer assays, respectively. Our results showed that FeUR exhibits a significant positive response only to sea ice meltwater, suggesting that DFe and algae provided by sea ice melting may be the main cause. In addition, the CFR had a slightly positive response to the freshwater input and a stronger correlation with the phytoplankton biomass, suggesting that the freshwater input may have enhanced the CFR through the algae released from sea ice melting. The FeUR normalized to the phytoplankton biomass was significantly positively correlated with the mixed layer depth, suggesting that water stability regulates the phytoplankton growth and the resulting Fe demand. A higher Fe demand per unit of carbon fixation during sea ice formation leads to a higher Fe/C ratio in phytoplankton. Although no significant correlations were observed between the FeUR, CFR, and meteoric water, meteoric water may have an effect on larger phytoplankton sensitive to Fe deficiencies. The results of culture experiments with DFe addition showed that the added Fe significantly enhanced the Fe uptake, carbon fixation, and Fe/C ratio of the cells, especially for micro-phytoplankton. The more pronounced response of micro-phytoplankton means that the meteoric water input may affect the efficiency of carbon export. Our study provides the first measurements of phytoplankton Fe quotas in the AS in austral late summer and early autumn, providing insights into how meteoric water and sea ice meltwater affect seasonal changes in Antarctic ecosystems. Full article

A Liquidambar formosana plantation is a kind of fast-grown forest in the subtropical region, providing a variety of ecosystem services such as superior wood, carbon fixation and oxygen release, and biodiversity maintenance. However, the ecological service function value of Liquidambar formosana plantations is not clear. To gain insights into the characteristics and importance of its ecological and economic benefits, the Liquidambar formosana plantation in the Tianjiling Forest Farm of Changsha City was taken as the specific research object in this paper. The ecological service function evaluation index system for Liquidambar formosana plantations was established based on the relevant research worldwide and the actual situation. The market value method, shadow engineering method, carbon tax method, and other environmental economics methods were used to estimate the value of seven ecological service functions (including organic matter production, carbon fixation and oxygen release, water conservation, soil conservation, soil improvement, air purification, and biodiversity maintenance) of the forest of Liquidambar formosana. The results indicated that the total economic value of ecological service function provided by the Liquidambar formosana plantation of Changsha was 103,277.82 RMB/(hm²·a), and the indirect economic value was 8.47 times that of the direct economic value. Among the seven ecological service functions, the value of carbon fixation and oxygen release was the highest (36,703.33 RMB·hm⁻²·a⁻¹), thus suggesting that the Liquidambar formosana plantation had strong photosynthesis and significant carbon fixation. This study directly reflects the value of forest ecological service function in the form of currency, which is beneficial to provide more insights into forest ecological service function so as to provide basic data and a scientific basis for the protection, construction, and promotion of the sustainable utilization and development of urban forest resources. Full article

In the context of carbon neutrality, it is increasingly important to reduce carbon and increase sinks, and urban green spaces play an important role in carbon sinks. In this paper, we used virtual reality (VR) and photoplethysmographic (PPG) technology to evaluate subject satisfaction regarding urban green space plant community landscape scenes using physiological eye movement and heart rate variability (HRV) data and psychological data obtained according to positive and negative emotional adjectives (PANA). The results of the study showed the following. (1) The physiological data showed the highest visual interest in single-layer grassland. The compound layer of tree-shrub-grass composite woodland communities resulted in the strongest comfort level. (2) The psychological subjective satisfaction evaluation scores were, in descending order: tree-shrub-grass composite woodland (T-S-G) > single-layer grassland (G) > tree-grass composite woodland (T-G) > single-layer woodland (T). (3) The correlation between interest, comfort, and subjective satisfaction was significant, which verified the feasibility of the model of “interest + comfort + subjective evaluation = comprehensive satisfaction”. The results of the study provide theoretical guidance for landscape design based on human perception preferences in the context of carbon neutrality as well as for the implementation of sustainable landscapes to achieve a win–win situation in which carbon sequestration and oxygen release benefits and aesthetics can coexist. The combined physiological and psychological evaluation model can also be applied to other landscapes. Full article

Forest ecosystems play an important role in maintaining the stability of the biosphere and improving the ecological environment. The valuation of forest ecosystem services provides data to support the implementation of forest ecosystem conservation and the development of ecological-compensation standards. We used multiple sources of data, such as remote-sensing and ground data, and we employed the methods of substitute market, shadow project, and contingent valuation. We valued the forest ecosystem services of Pudacuo National Park in Shangri-La, China, which consisted of six functions: soil conservation, forest nutrient retention, water conservation, carbon fixation and oxygen released, forest health care, and atmospheric environmental purification. The results showed that: the value of forest ecological services in Pudacuo National Park was 4.49 × 10⁹ yuan·a⁻¹, with higher values of carbon fixation and oxygen released, water conservation, and forest health care, in the following order: carbon fixation and oxygen released (3.85 × 10⁹ yuan·a⁻¹), water conservation (3.40 × 10⁸ yuan·a⁻¹), forest health care (1.44 × 10⁸ yuan·a⁻¹), soil conservation (1.15 × 10⁸ yuan·a⁻¹), forest nutrient retention (3.29 × 10⁷ yuan·a⁻¹), and atmosphere environmental purification (1.17 × 10⁷ yuan·a⁻¹). In addition, the value of services per stand and unit area is discussed, and the results of the study will inform the government’s ecological-compensation criteria in high-quality environmental areas. Full article

A paddy field ecosystem (PFE) is an important component of an agricultural land ecosystem and is also a special artificial wetland with extremely high value. Taking Tianjin (a municipality city in China) as the research area and using multi-source remote sensing data, we improved the accounting framework of the ecosystem service value (ESV) of PFEs and the calibration of model parameters. The ESV of PFEs was mapped at medium-high resolution and fine-grain at the provincial scale. The results showed that: (1) the net ESV of PFEs in Tianjin in 2019 was RMB 29.68 × 10⁸, accounting for 0.21% of GDP. The positive ESV was RMB 35.53 × 10⁸, the negative ESV was RMB 5.84 × 10⁸, and the average ESV per unit area was RMB 5.47 × 10⁴/ha; (2) as a proportion of the ESV of PFE, the value of climate regulation (61.27%) was greater than the value of carbon fixation and oxygen release (15.29%), which was greater than the value of primary products supply (8.08%). The production value of PFEs is far lower than their ESV; (3) the total net ESV in Baodi District was RMB 16.85 × 10⁸, accounting for 56.77% of Tianjin’s ESV, and the net ESV per unit area was RMB 5.72 × 10⁴/ha, both of which were higher than in other districts; (4) the pixel-based hot spots analysis showed that the number of hot spots (high-value ESV) and cold spots (low-value ESV) reached 98.00% (hot spots 56.9%, cold spots 41.1%) with a significant cluster distribution. The hot spots were mostly distributed in Baodi District (37.8%) and the cold spots were mostly distributed in Ninghe District (17.2%). The research results can support agricultural development, improve countermeasures according to local conditions, and provide theoretical support for regional land use planning, ecological compensation policy formulation and ecological sustainable development. Our methodology can be used to assess the impact of land use change on ESV. Full article

Land space underpins an ecological civilization. A thorough grasp of regional natural resources and subsequent optimization of the ecological security pattern are both essential for the comprehensive development and overall planning of the management of natural resources. In this study, we established and optimized the ecological security pattern in Shaanxi Province, China. Landscape patches distinguished by high importance of ecosystem services (carbon fixation and oxygen release, water conservation, habitat maintenance, and soil conservation) and high sensitivity of ecological environment to human interference (ecological sensitivity index) were extracted as ecological sources. An ecological resistance surface was built based on the following resistance factors: land-use type, topographic position index, and soil erosion intensity. A minimum cumulative resistance model was used to identify ecological corridors. Our results showed that those ecological sources with high to extreme ecological importance and sensitivity together covered an area of 67,457 km² (32.8% of the total land area of Shaanxi Province). A total of 32 ecological nodes were identified at the center of important ecological sources to serve as main areas for implementing ecological protection projects. In addition, 72 ecological corridors were identified, towards which efforts should be targeted to maintain their functions for the inter-connection and serial connection of ecological nodes and source patches. The ecological corridors create favorable habitats for wildlife and superior spaces for ecological migration based on the blue and green linear corridor system. According to these findings, we propose establishing an ecological security pattern featuring “two barriers, three belts, and multiple corridors” in Shaanxi Province and that the green ecological security barriers should be strengthened based on their natural background and resource endowments. Full article