Ecological Restoration Strategies Research Articles

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

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.

An analysis on the spatial heterogeneity characteristics of landscape ecological risk in Qilian Mountain National Park

As a key ecological function area and a priority area for biodiversity conservation in China, Qilian Mountain National Park is facing a severe test of its ecological environment, and the study of its landscape ecological risk is of great significance to the construction and high-quality development of the Qilian Mountain National Park. In this research, based on land use data from six periods (i.e., year in 1995, 2000, 2005, 2010, 2015, and 2020) in the Qilian Mountain National Park, we divided the ecological risk plots, calculated the landscape pattern, and constructed the landscape ecological risk index to deeply explore the temporal and spatial heterogeneity of landscape ecological risk in Qilian Mountain National Park by using ArcGIS, Fragstats and GeoDa. The results showed that: Grassland is the predominant land use type, the area covered by woodland and grassland have exhibited a significant increase since 1995. Landscape fragmentation and disturbance indices exhibit fluctuations across different years, but showed an overall decreasing trend, and landscape stability was improved in the study area. There were obvious differences in the disturbance indices of different landscape types, with grassland and bare land having the highest values. Ecological risk in the study area is heterogeneous, with an overall low ecological risk and a shift to a lower risk level, and a decreasing trend in ecological risk, which is positively correlated spatially and mainly manifested as a “low-low” aggregation. Global warming and unreasonable human activities have exacerbated the ecological degradation of Qilian Mountain National Park, but a series of ecological restoration strategies after the establishment of the national park have gradually improved the regional ecological environment.

Soil gravel content and plant species configuration control vegetation restoration in Qinghai‐Tibet Plateau

AbstractSoil gravel content strongly affects ecological restoration; however, the response and mechanism of plant traits to soil gravel content under the sensitive and fragile natural environment of Qinghai‐Tibet Plateau remains unclear. Herein, soils with three gravel content (10%, 30%, 50%) in the southeastern Tibetan Plateau were selected, and three plant species (one native plants of Elymus dahuricus (Ed), and two introduced ones of Festuca elata (Fe) and Medicago sativa (Ms)) were used in seven planting patterns with different proportions (Fe, Ed, Ms, Fe + Ed (1:1), Fe + Ms (2:1), Ed + Ms (2:1), Fe + Ed + Ms (2:2:1)). Plant traits, phytochemical properties and soil stoichiometric characteristics were measured to explore the interactive effects of soil gravels and plant species on vegetation restoration. Average plant height, coverage, shoot biomass, and total biomass were most affected by plant species (F = 277–611, p < 0.01), followed by gravel content (F = 90–195, p < 0.01) and their interaction (F = 5–51, p < 0.05); root biomass was most affected by gravel content (F = 130, p < 0.01). Among plant species, shoot and root biomass, total biomass overall decreased in the order of Fe + Ed + Ms>Fe>Fe + Ms>Fe + Ed>Ms>Ms + Ed>Ed. Plant total biomass, shoot biomass, root biomass and shoot/root ratio among different soils overall decreased in the order of low> high> medium gravel contents. All plant species were restricted by soil nitrogen except for Ed and Ed + Ms (N:P > 14). In addition, increasing the gravel content in the soil will increase the soil bulk density and reduce the total soil porosity. The total soil porosity is significantly positively correlated with the average plant height, coverage, aboveground biomass, and total biomass of plants (r = 0.78–0.91, p < 0.05). The total nitrogen content, total phosphorus (TP) content, and N: P in rhizosphere soil were significantly positively correlated with the average plant height, coverage, aboveground biomass, root biomass, and total biomass of plants (r = 0.70–0.97, p < 0.05), but soil N was significantly positively correlated with aboveground biomass and total biomass (r = 0.69, 0.71, p < 0.05), and there was no significant difference in soil TP content between them. The gravel content directly affects plant growth by changing bulk density and total porosity, but the combined effect of soil nutrients and plants affects plant growth. Therefore, optimizing the configuration of soil properties (mainly nitrogen and compactness) and plant species (isecologic niche plants) is an effective strategy for ecological restoration in the Qinghai‐Tibet Plateau.

The feedback of greening on local hydrothermal conditions in Northern China

Northern China has experienced a significant increase in vegetation cover over the past few decades. It lacks a comprehensive understanding of how greening impacts local hydrothermal conditions. To address this issue, in our study, the RegCM-CLM45 model was used to conduct a thorough assessment of the impacts of greening on temperature, vapor pressure deficit (VPD), precipitation, and soil moisture. The findings revealed that the local climatic effects of greening varied across different drought gradients based on the aridity index (AI). In drier regions with AI<0.3, the increased energy induced by greening tended to dissipate as sensible heat, exacerbating both warming and drought conditions. Conversely, in wetter regions with AI>0.3, a greater proportion of energy was lost through evapotranspiration, attenuating warming. Additionally, greening enhanced precipitation and soil moisture in drier regions and moderated their decline in wetter regions. Significantly, our research emphasized the effectiveness of grassland expansion and conservation as prime strategies for ecological restoration, particularly in drylands, where they could effectively alleviate soil drought. Given the diverse responses of different land cover transformations to local hydrothermal conditions in drylands, there is an urgent need to address potential adverse effects arising from inappropriate ecological restoration strategies and to develop an optimal restoration framework for the future.

Uncovering the complex relationship between plant diversity, soil properties, and mycorrhizal inoculum potential in threatened Miombo woodlands

AbstractArbuscular mycorrhizal fungi (AMF) are key members of soil microbial communities and play a key role in regulating ecosystem processes. However, the mutual interdependence of plants and AMF in threatened Miombo woodlands has not yet been fully elucidated. In this study, we investigated the relationship between plant ecological indicators and soil mycorrhizal inoculum potential (MIP) in the Miombo forest fallow of Haut‐Katanga, Democratic Republic of Congo, and identified plant species that positively influence soil MIP. We conducted a floristic inventory on 32 plots and collected soil cores for physicochemical and AMF characterization. Trap cultures using Crotalaria juncea seedlings were performed to determine the soil MIP. We also tested the AMF colonization status of randomly collected living roots of mature woody and dominant herbaceous species to identify explanatory variables for MIP. Our results showed that MIP was twice as high in silty clay soils (63.13%) than in clay soils (30%). Furthermore, MIP increased accordingly with the relative abundance of a group of woody and herbaceous species (e.g., Albizia adianthifolia, Baphia bequaertii, and Setaria pumila) and decreased with others (e.g., Combretum collinum, Harungana madagascariensis and Hyparrhenia diplandra). Linear regressions showed that MIP increased significantly with the specific richness of woody species identified as indicators and with the amount of annual herbs. Woody legumes with high root colonization by AMF appeared to be refuge plants, and primary AMF dispersal vectors, increasing soil MIP. This study provides baseline data that can be used to formulate ecological restoration strategies, including soil and vegetation protection.

Spatio-temporal Variation in Net Primary Productivity of Different Vegetation Types and Its Influencing Factors Exploration in Southwest China

Studying the spatiotemporal variation in vegetation net primary productivity (NPP) and exploring its influencing factors are of considerable practical significance for understanding the spatiotemporal variation in vegetation and for guiding ecological restoration and management projects based on local conditions. Based on MODIS NPP data, combined with in situ meteorological data, land use data, and vegetation type data, this study explores the spatiotemporal variation in different types of vegetation NPP in southwest China via the Mann-Kendall significance test and Theil-Sen Median slope estimator. It reveals the influencing factors of spatial differentiation of different types of vegetation NPP and the interaction between influencing factors in combination with stability analysis and Geo Detectors. The results revealed that on the temporal scale, from 2000 to 2021, vegetation NPP, NPPPre (vegetation NPP exclusively under the influence of climate change), and NPPRes (vegetation NPP exclusively under the influence of human activities) in southwest China showed a fluctuating upward trend. Among different vegetation types, NPP, NPPPre, and NPPRes exhibited an upward trend, except for a minor decline in NPPRes of tree vegetation at a rate of -0.183 g·(m2·a)-1. Among them, NPP, NPPPre, and NPPRes of economic vegetation showed the most significant upward rates, 5.96, 3.09, and 2.94 g·(m2·a)-1, respectively. On the spatial scale, the tree vegetation NPP with the most significant downward trend was mainly distributed in Tibet and southern Yunnan, while the economic vegetation NPP with the highest upward trend was primarily distributed in eastern Sichuan Province. The stability of vegetation NPP in southwest China presented a spatial distribution pattern of "low in the south and high in the north," and the average value of the correlation coefficient increased in the ascending order of arbor vegetation (0.101), shrub vegetation (0.105), herb vegetation (0.110), and economic vegetation (0.114). The interaction between surface temperature and relative humidity was the main influencing factor for spatial differentiation of vegetation NPP, while the interaction between sunshine duration and warmth index had the most significant impact on vegetation in southwest China, with an increasing percentage of 30.91%. Different types of vegetation had different requirements for different climatic factors, but their requirements for surface temperature and warmth index were significantly consistent. When the surface temperature was 21.03-28.49℃, and the warmth index was 106.46-167.2, the NPP of different vegetation types peaked. Under natural succession, the impact of climate change on vegetation was inversely proportional to the stability of the vegetation community. The arbor vegetation community with high stability was less affected, while the herb vegetation community with low stability was highly affected by climate. In contrast, the stability of economic vegetation was directly proportional to the impact of climate due to the influence of human activities. This study establishes a theoretical foundation for evaluating the impact of regional climate on the growth of different vegetation types and can be crucial for formulating ecological restoration and management strategies in southwest China that are adapted to the local conditions.

Marine ecological restoration strategies of coastal nuclear power plants in China

Low-carbon and green development model is the choice for responding to climate change. Under the dilemma between ever-growing energy demand and the associated environmental issues, nuclear power is one of the low-carbon and high-efficient energy options which compared to wind power and solar power. It is the only stable power source that can replace fossil energy on a large scale at present and even in the future. This paper briefly describes the operational risks of coastal nuclear power plants (CNPPs) and the upgrade process of nuclear reactors, systematically analyzes and summarizes the ecological environment problems, risk problems and ecological restoration and protection strategies in the construction and operation of CNPPs, including coastal wetland ecological environment, marine ecological environment, and the risk prevention measures for cooling water source. The results show that ecosystem restoration by human does not make up for the weakening of the ecological carrying capacity and ecosystem away from its baseline, nonetheless, the restoration of important wetland habitats is conducive to the improvement of the functions of key marine ecosystems and the maintenance of marine biodiversity.

Effects of Abiotic Factors on Plant Community Composition and Functional Traits in the Liaohe Estuary

The composition and functional traits of plant communities and their changes along an environmental gradient are important bases for maintaining the carbon sinks of estuarine wetlands. To clarify the succession pattern of plant community in an estuary along an environmental gradient, this study considered the Liaohe Estuary wetland as the research object and divided the dominant plant community into a Phragmites australis community and high-, medium-, and low-density Suaeda salsa communities. We employed redundancy analysis, variance decomposition, and multiple regression to examine the impact of an environmental gradient on the functional traits and spatial distributions of plant communities in the Liaohe Estuary wetland. The findings revealed that as the elevation decreased, the soil salinity increased and the water content decreased. The distribution of plant communities followed the order of P. australis, high-density S. salsa, medium-density S. salsa, low-density S. salsa, and bare flat areas. When the soil salinity exceeded 21 g/kg and the soil moisture content was below 17%, the conditions were no longer suitable for the growth of S. salsa or P. australis. Soil salinity, total nitrogen content, clay content, and elevation were the most critical environmental factors affecting the functional traits of the plant communities. Soil biochemical characteristics, soil texture, and the physical environment accounted for 28.9%, 23.12%, and 11.51%, respectively, of the variation in the spatial distribution of plant communities. The proportions of the suitable area for the high-, medium-, and low-density S. salsa were 13.1%, 53.78%, and 33.12%, respectively. The results provide a theoretical basis for further elucidating the degradation mechanisms of estuarine wetlands, developing an evaluation index system for estuarine wetland ecological restoration, and optimizing ecological protection and restoration strategies.

Evaluating water quality change with hydrologic restoration in the Western Everglades (Florida, USA), an application of WAM

Hydrologic restoration at the watershed scale is a complex process that can influence other processes and conditions within the watershed and downstream systems. Given these interrelated watershed scale processes, tools like models are essential to assess the potential effectiveness of sub-watershed to regional remediation strategies for ecological restoration. The goal of Everglades restoration is to restore the quality, quantity, and timing of water to one of the most ecologically unique and complex systems. This study aimed to evaluate changes to water quality associated with hydrologic restoration efforts within the Feeder Canal Basin as identified by the Western Everglades Restoration Project (WERP) by demonstrating, through simulations the potential effectiveness of implementing water quality remediation measures such as Best Management Practices (BMPs) and Stormwater Treatment Areas (STAs) within the WERP area. Additionally, to understand potential phosphorus sources and pre-develpoement conditions within the basin, a pre-development baseline was developed. Using the Watershed Assessment Model (WAM) various model alternatives including the WERP tentatively selected plan (TSP) were developed for a 22 year period of simulation. The implementation of both moderate and aggressive BMPs significantly reduced total phosphorus concentrations within the canal system at various levels indicating an improvement to near-field conditions. Meanwhile, not until the moderated BMPs and operation of an STA do water quality improvement become realized further downstream. The combined strategy of BMPs and STA demonstrates the integrated nature of nutrient remediation with both near and far-field benefits to the system with hydrologic restoration. This integrated strategy of water quality and hydrologic restoration can lead to a more sustainable and resilient restored ecosystem.

Discussion on ecological restoration strategy of water conservancy project -- A case study of Shirase Reservoir in Quanzhou City

Because of the water conservancy project construction to the environment has brought a lot of damage, the state for environmental pollution and damage problems began to carry out a comprehensive restoration, for the relevant environmental protection and restoration policies are also improving, with the implementation of relevant measures, ecological water conservancy projects will play a vital role in environmental governance. In order to put forward suggestions for ecological restoration of white rose reservoir, this paper puts forward suggestions for ecological restoration from the geographical location of the water conservancy project, the measures in the construction process and the operational measures after completion, so as to restore the ecological role played by the ecological area before the completion of the water conservancy project and reduce the secondary pollution and damage to the environment in the operation process after it. This paper discusses the importance of ecological water conservancy project in environmental governance, and takes Shirase reservoir as an example, puts forward the ecological restoration suggestions for the water conservancy project. In order to restore the ecological function of the area before the water conservancy project and reduce the secondary pollution and damage in the operation process, it is suggested to improve the area from three aspects: geographical location, construction process and operation measures after completion. Through the implementation of ecological restoration measures, it will help to realize the harmonious symbiosis between man and nature.

Identification of ecologically sensitive zones affected by climate change and anthropogenic activities in Southwest China through a NDVI-based spatial-temporal model

Revealing the driving mechanism of climatic change and anthropogenic activities on vegetation variation and identifying the ecologically sensitive zones in Southwest China are critical for formulating regional ecological restoration strategies. Herein, a NDVI-based spatial–temporal model in Southwest China from 2000 to 2021 under the influences of climatic change and anthropogenic activities alone and in combination was determined based on MODIS NDVI and in situ meteorological data using Theil-Sen median analysis, the Mann–Kendall significance test, residual analysis, and relative analysis. The results showed that on the annual scale, the NDVI, predicted NDVI, and residual NDVI significantly increased at rates of 0.0016 yr−1, 0.0008 yr−1, and 0.0008 yr−1 in Southwest China from 2000 to 2021, respectively. Moreover, the NDVI, predicted NDVI, and residual NDVI significantly (P < 0.05) increased in the Guangxi Hills (GXH), Hengduan Mountains (HDM), Sichuan Basin (SCB), Yunnan-Guizhou Plateau (YGP), Zoige Plateau (ZP) and Tibetan Plateau (TP). The areas with an increase in the NDVI, predicted NDVI, and residual NDVI accounted for 81.45 %, 79.73 %, and 71.20 % of Southwest China, respectively. The NDVI variation in Southwest China was dominated by the combined effects of climatic change and anthropogenic activities, accounting for 83.22 % of the total study area. In addition, 62.76 % of the study area exhibited a greening trend. The contributions of climatic change were greater than those of anthropogenic activities for greening areas, and the opposite is true for browning areas. Innovatively, ecologically sensitive zones were identified through the Theil-Sen median analysis and Mann–Kendall significance test and accounted for 16.78 % of the total study area. Overall, this study proposed a NDVI-based spatial–temporal mode to investigate the driving mechanism of driving forces on NDVI variation, identify ecologically sensitive zones and suggest a management framework in Southwest China.

Effects of driving factors on water supply function under different basins and spatial scale in Zoige alpine wetland, China

Water supply is one of the core ecosystem services functions for wetland. Due to the important status of Zoige wetland, assessment of water supply in Zoige wetland is significant for ecological security all over the world. In this paper, Heihe and Baihe basins in Zoige wetland were taken as research objects, the water yield module of the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model was used to spatially quantify water supply, with the aims of revealing the driving mechanism of water supply under different basins and spatial scale. We observed the spatial pattern change of water yield under baseline and eleven future scenarios and used the ANOVA of repeated measures and multiple linear regression model to explore the patterns and driving factors of water supply in Heihe and Baihe rivers basins. The research results were as follow. (1) The precipitation is main factor to improve water yield, but this intensity is different in different basins and spatial scale. Topography, climate, vegetation, and percentage of wetland conditions have important impacts on water yield services. However, the impacts of these conditions on water yield were various significantly across different watersheds and spatial scales (excluding factors such as precipitation, slope, and percentage of swamp wetland). (2) The spatial pattern of water yield main was affected by land use change and the amount of water yield main was affected by future climate change. (3) Water yield in the Baihe basin was more sensitive to climate change, while the Heihe basin is more sensitive to land use changes. Wetland ecological restoration strategies can effectively improve regional water yield, especially in the Heihe basin. (4) In all scenarios, the southeast regions of the study region were both the main hot spots of water yield. Wetland ecological restoration strategies have added hot spots in the north regions of the Baihe river basin, reduced hot spots in the middle-south regions of the Heihe basin.

Mechanisms of microbial-driven changes in soil ecological stoichiometry around gold mines

In this study, we used soils with different pollution and nutrient levels (non-polluted S1, highly polluted low-nutrient S2, and highly polluted high nutrient S3) around the gold mine tailing ponds, and combined with metabolic limitation modeling and macro-genomics approaches, aiming to investigate the relationship between soil microbial composition and soil eco-chemometrics characteristics under heavy metal stress. The results showed that heavy pollution resulted in reduced SOC, TN, microbial biomass, and with C- and P- acquisition (BG, CBH, ALP) as well as nitrogen limitation of soil microbial metabolism in soils (S2, S3). Further analysis by macrogenomics showed that heavy metal contamination led to an increase in α-microbial diversity and altered the composition of microbial communities in the soil. The cycling of C, N, and P nutrients was altered by affecting the relative abundance of Anaeromyxobacter, Steroidobacter, Bradyrhizobium, Acidobacterium, Limnochorda (predominantly in the Ascomycetes and Acidobacteria phyla), with the most pronounced effect on the composition of microorganisms synthesizing C-acquiring enzymes, and heavy metals and pH were the main influences on ecological stoichiometry. The results of this study are useful for understanding the sustainability of ecological remediation in heavy metal contaminated areas and for developing ecological restoration strategies.

Study on remote sensing inversion and temporal-spatial variation of Hulun lake water quality based on machine learning

Hulun Lake is facing significant water quality degradation, necessitating effective monitoring for safety. Traditional methods lack the necessary spatial and temporal coverage, underscoring the need for a remote sensing model. In this study, we utilized the Landsat 8 OLI dataset, incorporating cross-section monitoring and field sampling data comprehensively. Employing the random forest algorithm, we constructed a remote sensing inversion model for six water quality parameters in Hulun Lake: chlorophyll-a (Chl-a), total nitrogen (TN), total phosphorus (TP), ammonia nitrogen (NH3−N), chemical oxygen demand (COD), and dissolved oxygen (DO). The model was applied to the non-freezing period of Hulun Lake from 2016 to 2021, exhibiting commendable performance and generating high-resolution maps. Time series analysis revealed that during the study period, the pollution levels of TN, TP, and COD in Hulun Lake were extremely serious, exceeding the Class V water standard of China's surface water environmental quality standard. Regional analysis indicated lower pollutant concentrations in the central lake area compared to the lake inlet. The inflowing rivers with high pollution adversely impacted Hulun Lake's water quality. To ensure the continued health of Hulun Lake's water quality, it is imperative to monitor lake water quality attentively and implement necessary measures to prevent further deterioration. This study holds crucial importance for shaping and executing ecological protection and restoration strategies for Hulun Lake.

Restoring historical grasslands in a desert national park: Resilience or unrecoverable states in an emerging climate?

Ecosystems that supported multiple biological communities during the Holocene and that form alternative stable states pose challenges for identifying appropriate and feasible target communities for ecological restoration and conservation strategies for climate adaptation. In the Chihuahuan Desert, shrubland and perennial grassland alternatively dominated for millennia. However, grassland declined beginning 100–150 years ago during concomitant change in both climate and anthropogenic land use, making it unclear whether restoring grassland is appropriate or feasible in the emerging climate. In Guadalupe Mountains National Park, Texas, USA, we characterized remnant grasslands and performed experiments including outplanting and shrub reduction to assess feasibility and techniques for restoring desert grassland. In remnant patches, grass cover was more temporally variable than shrub cover, as grass cover varied 1.5× between years. Survival of outplanted grasses, either under Larrea tridentata shrubs or in the open with or without woody material encircling outplants for protection, was high (95 %) after seven months but declined to 2 % after 19 months. Response of perennial grass cover was variable after shrub and litter removal on soil surfaces varying in stoniness. Results suggest that 1) restoration can increase native desert grasses but gains may be intermittent; 2) reducing shrubs to facilitate natural expansion of remnant grasses and propagules may be more effective than outplanting grasses; and 3) restoring native grassland by reducing shrubs appears feasible even in dry conditions projected for the emerging climate. Findings that native grasses can increase at least intermittently suggest that practitioners have multiple candidate communities for conservation management and climate change adaptation as grassland, shrubland, and mixed communities each provide unique habitat.

Human activities significantly impact China’s net primary production variation from 2001 to 2020

Formulating ecological restoration strategies requires accurately quantifying how climate and anthropogenic factors influence net primary production (NPP). A Carnegie-Ames-Stanford approach (CASA) model was applied to estimate China’s terrestrial NPP from 2001 to 2020. We adopted a random forest (RF) method to identify the main driving forces for NPP change in China. Total NPP in China increased noticeably with a 24.91 Tg C/yr rate, as shown in our results. The significantly increased NPP was mainly attributed to human activities (64.29 ± 0.17%), chiefly due to human management and ecological projects (afforestation or other) fostered vegetation growth. The primary drivers of NPP variation varied in different geographic regions. Climate dominated the NPP dynamic in north China (52.38 ± 0.91%), where the main factor that restricted the increase of NPP was precipitation. Human activities strongly impacted the NPP variation in the remaining regions. Human management measures increased NPP in northwest and southwest China. In the northeast, east, and south-central China, the NPP change resulted from land use change, primarily grassland, cropland, and forest change. Collectively, our study expands the understanding of the driving forces of NPP change, informing different strategies for achieving ecological restoration and carbon neutrality.

Reforestation regulated soil bacterial community structure along vertical profiles in the Loess Plateau

IntroductionReforestation is a widely used strategy for ecological restoration in areas facing ecological degradation. Soil bacteria regulate many functional processes in terrestrial ecosystems; however, how they respond to reforestation processes in surface and deep soils remains unclear.MethodsArtificial Robinia pseudoacacia plantation with different stand ages (8, 22, and 32 years) in a typical fallow forest on the Loess Plateau was selected to explore the differential response of soil bacterial community to reforestation in different soil depths (surface 0–200 cm, middle 200–500 cm, and deep 500-100 cm). Soil bacterial diversity, community composition and the co-occurrence patterns, as well as the functions were analyzed.Results and discussionThe results showed that alpha diversity and the presence of biomarkers (keynote species) decreased with the increasing soil depth, with a sharp reduction in family-level biomarker numbers in 500–1,000 cm depth, while reforestation had a positive impact on bacterial alpha diversity and biomarkers. Reforestation induced a more loosely connected bacterial community, as evidenced by an increase of 9.38, 22.87, and 37.26% in the average path length of the co-occurrence network in all three soil layers, compared to farmland. In addition, reforestation reduced the hierarchy and complexity but increased the modularity of the co-occurrence network in top and deep soil layers. Reforestation also led to enrichment in the relative abundance of functional pathways in all soil layers. This study sheds light on the strategies employed by deep soil bacteria in response to reforestation and underscores the significant potential of deep soil bacteria in terrestrial ecosystems, particularly in the context of human-induced environmental changes.

Insight into the nutrient change in freshwater ecosystem under ferrous addition: Revealed by phosphorus, nitrogen, and microbial community

Restoration of submerged macrophytes in freshwater ecosystems is a widely utilized and effective way for controlling eutrophication, but it's not enough for the endogenous nutrient removal. Incubation experiments were conducted in this study to explore the effects of ferrous addition on the nutrients and rhizosphere microorganisms. The ferrous addition with different dosages has different effects on the phosphorus (P), nitrogen (N) and other properties in the freshwater ecosystem with submerged macrophyte growth. The ferrous addition can affect the nitrogen cycling of water and sediments significantly by affecting the functional bacteria related to the nitrogen cycling in rhizosphere sediment. The genera related to denitrification (e.g., Thiobacillus), ammonification (e.g., Chitinophaga) and nitrification (e.g., Nitrospira) were enriched with the ferrous addition above 0.5 mg/L. On the contrary, the relative abundance of Clostridium_sensu_stricto_1 which was related to dissimilarity nitrate reduction to ammonium (DNRA) decreased after ferrous addition. The relative abundance of functional genera associated with iron cycle were enriched, especially the Ferritrophicum and Thiobacillus. Ferrous addition can successfully control phosphorus levels in the water at a low concentration (0.02 mg/L) and help with the stabilization of phosphorus in sediment. Considering the effects of iron on nutrients and microorganisms at different dosages, 5.0 mg/L is recommended to promote endogenous nitrogen removal and sediment phosphorus stabilization in freshwater ecosystems with submerged macrophytes. These findings contribute to the ecological evaluation of ferrous addition, and provide a reference or strategy for ecological restoration with submerged macrophyte especially V. natans in freshwater ecosystems.

Identification and optimization strategy of ecological security pattern in Maiji District of Gansu, China

One of the crucial areas of research in land space planning in China is finding ways to coordinate urban development and ecological preservation since the rapid growth of cities has led to numerous environmental issues. It is highly important to enhance the regional ecological environment and economy, thereby improving human well-being, by optimizing the spatial arrangement of ecosystems and identifying areas that need ecological restoration within the national land space. This study was conducted in Maiji District, where a combination of MSPA (Multiple Scale Pattern Analysis) and service function methods were employed to evaluate the ecological resources, identify critical ecological corridors, optimize the ecological security pattern, determine priority areas for ecological restoration in the land space, and formulate strategies for ecological restoration. The results indicated that in Maiji District, the ecological source area covers 93277 ha, which represents 26.78 % of the total administrative region. Within the southeastern part of Maiji District, there are 28 significant ecological corridors, with a combined length of 333.80 km. Based on the existing ecological resistance surfaces, ecological sources, and ecological corridors, a plan for ecological restoration has been developed for Maiji District, known as the “one belt, one screen, two areas, five corridors, and multiple points” ecological restoration pattern. This plan serves as a guideline for identifying suitable areas for ecological restoration, security pattern, and creating restoration plans for the Maiji District land.

Influence of forest vegetation restoration on carbon increment after mining

We have clarified the study area has a history of 65 years and has been restored for 6 years. This study investigated the carbon storage characteristics of undisturbed natural forests and restored mining vegetation in Yunnan Province, China. The goal was to quantify carbon reserves and increments to inform ecological restoration strategies. Four vegetation components (tree, shrub, herb, litter) and five soil layers (0–10, 10–20, 20–30, 30–40, 40–60 cm) were analyzed. In natural forest, the tree layer stored 60% of carbon (273 Mg ha−1), overwhelmingly dominating vegetation carbon stocks. Shrub, herb, and litter layers each comprised < 1%. Surface soil layers (0–30 cm) stored 64% of soil carbon. In the restored mining area, the tree layer contributed 75% of vegetation carbon increment (16 Mg ha−1), though stocks were lower than natural forest. Soil layers showed the highest carbon increment (69%) despite lower biomass than natural conditions. Unexploited forests thus exhibit robust carbon storage, while restored mining areas have weaker carbon gains, indicating recovery potential. Strategic interventions targeting soil quality, stimulating vegetation growth, and increasing carbon sequestration could significantly augment reserves and ecological functionality. Prioritizing vegetation succession and soil revitalization are paramount to ensuring ecological integrity and sustainable development. Fostering a positive regional ecological feedback loop will be pivotal. This research quantifies carbon storage differences between undisturbed and restored mining areas, highlighting soil and vegetation as critical targets for optimizing carbon sequestration and ecosystem recovery in degraded environments.