Effective Ecosystem Management Research Articles

Temperate forest understory vegetation shifts after 40 years of conservation

Understanding how vegetation composition and diversity respond to global changes is crucial for effective ecosystem management and conservation. This study evaluated shifts in understory vegetation after 40 years of conservation within Drawa National Park (NW Poland), to check which plant communities changed the most, and whether vegetation shifts reflect global change symptoms (climate change and pollution) or natural forest dynamics. Using ordination and generalized mixed-effects linear models, we assessed changes in alpha diversity metrics, accounting for taxonomic, functional, and phylogenetic aspects within 170 quasi-permanent plots, surveyed in 1973–85 and resurveyed in 2015–19. We found an overall homogenization of forest vegetation and specific shift patterns in certain forest associations. In coniferous and nutrient-poor broadleaved forests, the overall number of species increased due to the replacement of functionally distinct or specialized species with more ubiquitous species that could exploit increased resource availability. In riparian forests and alder carrs we found either shifts from riparian forest to alder carrs or to mesic broadleaved forests. The most stable communities were fertile broadleaved forests. Our study quantified shifts in taxonomic, functional, and phylogenetic diversity after 40 years of conservation and provides important insights into the shifts in vegetation composition in temperate forest communities. In coniferous and nutrient-poor broadleaved forests we found an increase in species richness and replacement of functionally distinct or specialized species by ubiquitous species, indicating increased resource availability. Shifts between wet broadleaved forests and transition into mesic forests suggest water limitation, which can be related to climate change. The most stable were fertile broadleaved forests fluctuating due to natural stand dynamics. The findings highlight the need for ongoing monitoring and management of ecological systems to preserve their diversity and functionality in the face of global changes.

Scale effects on the supply–demand mismatches of ecosystem services in Hubei Province, China

Understanding the patterns, relationships, and driving forces between ecosystem services (ESs) supply–demand at multiple spatial scales can facilitate sustainable hierarchical management. However, the scale effects of ESs supply–demand mismatches were typically ignored, resulting in inadequate targeted ecosystem promotion policies. This study identified the supply–demand mismatches of the key ESs (grain production, water yield, carbon sequestration, and soil conservation) using the ecological supply–demand ratio and bivariate Moran's I at three grid and county scales from 2000 to 2020 in Hubei Province, China. Then the spatial regression models were applied to explore the driving forces of these mismatches. The major results revealed that (1) Hubei Province and counties located away from urban areas were self-sufficient in the ESs supply–demand, but the numbers of these counties declined over the twenty years. The characteristics of ESs mismatches in some patches may be obscured at coarser scales. (2) The directions of socioecological drivers were robust, but their intensities changed significantly at the four scales. The normalized difference vegetation index was the primary positive driver at the fine scale, while population, economy, and proportion of construction land became dominant drivers at coarser scales. Factors influencing mismatches were more diverse at the fine scale compared to the coarse scale. (3) Efficient strategies were scale-dependent and place-based. Different management units should clarify their responsibilities and strengthen linkages between upper and lower levels to achieve sustainable ESs development. At the provincial level, strengthening interregional cooperation and allocating surplus grain and water resources from the southwest to urban regions contributes to balancing regional ESs. At the county level, adopting region-specific strategies based on delineating ESs management zones is crucial. At finer management levels, incorporating micro-scale mismatch locations and natural background information can provide valuable guidance for localized ecological protection and restoration projects. The findings underscore the strengths of conducting assessments of ESs supply–demand at multiple scales, enabling different government levels to enhance effective ecosystem management and prevent misinformation.

High-Frequency Observations of Cyanobacterial Blooms in Lake Taihu (China) from FY-4B/AGRI

China’s FY-4B satellite, launched on 3 June 2021, is a new-generation geostationary meteorological satellite. The Advanced Geosynchronous Radiation Imager (AGRI) onboard FY-4B has 15 spectral channels, including 2 visible (470 and 650 nm), 1 near infrared (825 nm), and 3 shortwave infrared (1379, 1610, and 2225 nm) bands, which can be used to observe the Earth system with the highest spatial resolution of 500 m and 15 min temporal resolution. In this study, FY-4B/AGRI observations were applied for the first time to monitor cyanobacterial blooms in Lake Taihu, China. The AGRI reflectance at visible and near-infrared bands was first corrected to surface reflectance using the 6S radiative transfer model. Due to the similar spectral reflectance characteristics to those of land-based vegetation, the normalized difference vegetation index (NDVI) and some other remote sensing vegetation indices are usually used for the retrieval of cyanobacterial blooms. The fractional vegetation cover (FVC) of algae, defined as the fraction of green vegetation in the nadir view, was adopted to depict the status and trend of cyanobacterial blooms. NDVI and FVC, the two remote sensing indices developed for the retrieval of land vegetation, were used for the detection of cyanobacteria blooms in Lake Taihu. Finally, the FVC derived from AGRI measurements was compared with that obtained from the Advanced Himawari Imager (AHI) onboard the Himawari-8 satellite to validate the effectiveness of our method. It was found that atmospheric correction can substantially improve the determination of the normalized difference vegetation index (NDVI) values of cyanobacterial blooms in the lake. As a proof of the robustness of the algorithm, the NDVIs are both derived from both AGRI and AHI and their magnitudes are similar. In addition, the distribution of cyanobacterial blooms derived from AGRI FVC is highly consistent with that derived from FY-3D/MERSI and EOS/MODIS. While a lower spatial resolution of FY-4B/AGRI might restrict its capability in capturing some spatial details of cyanobacterial blooms, the high-frequency measurements can provide information for the timely and effective management of aquatic ecosystems and help researchers better quantify and understand the dynamics of cyanobacterial blooms. In particular, AGRI can provide greater details on the diurnal variation in the distribution of cyanobacterial blooms owing to the high temporal resolution.

Anthropogenic threats associated with mortality and biomass of stranded sea turtles on the northern coast of São Paulo State, Brazil

ABSTRACT Beach monitoring programmes along the Brazilian coast in recent years have provided stranding data which can be analysed to show the effects of human impacts on sea turtle populations. In Brazil, the five species recorded are threatened with extinction. In this study, data from strandings of sea turtles on the northern coast of the State of São Paulo, Brazil, over six years (2015–2021), were used to evaluate whether human activities are associated with impacts on the populations and to analyse the effects of seasonality on abundance. There were 6411 strandings of sea turtles, the majority being Chelonia mydas, followed by Caretta caretta, Lepidochelys olivacea, Eretmochelys imbricata and Dermochelys coriacea. Strandings occurred mainly during winter and spring. Where it was possible to determine the cause of death of an individual, there were several associations with anthropogenic factors, mainly solid waste, fishing gear, collisions with vessels, injuries and dredging. The high incidence of strandings of sea turtles on the Brazilian coast, mostly juveniles, and the great impact of anthropogenic factors in the causa mortis indicate the need to adopt ocean education strategies and public policies that can establish effective management and conservation plans of marine ecosystems.

Coastal Wetland Restoration Strategies Based on Ecosystem Service Changes: A Case Study of the South Bank of Hangzhou Bay

A unique variety of wetlands known as coastal wetlands that connect terrestrial and marine ecosystems is crucial to reducing and adapting to climate change as well as the advancement of human culture. However, the coastal wetland ecosystem is currently in danger as a result of the increasing intensity of human activity, and wetland restoration and reconstruction have garnered a lot of interest. The differentiated ecological restoration strategies based on ecosystem service change analysis can provide a reference for the effective management and sustainability of coastal wetland ecosystems. The InVEST model and ArcGIS were used to analyze the spatiotemporal changes in ecosystem services before and after the implementation of coastal wetland restoration policies based on remote sensing image data, meteorological and soil data, etc. The ecological restoration pattern of coastal wetlands was divided, and the corresponding ecological restoration strategies were proposed in this study. The following are the results: (1) there are still many wetlands that have been converted to non-wetlands following the implementation of the wetland restoration policy, and the ecosystem services as a whole exhibit a rising and then falling trend, with a rise from 2005 to 2015, a fall in 2015 due to the creation of Hangzhou Bay New District, and a slight improvement to 2020. Among them, the water yield increased continuously, the carbon storage fluctuated, and the habitat quality did not improve significantly. (2) The hot spots of ecosystem services were concentrated in the south and southeast of the study area, with no obvious cold spots. (3) By comprehensively analyzing the changes and spatial patterns of ecosystem services, the coastal wetlands on the south bank of Hangzhou Bay were divided into an ecological conservation zone, a green development zone, and an ecological restoration zone at the township level, and corresponding optimization strategies were proposed. The results can provide a reference for the fine-grained and differentiated management of regional ecosystem services.

Construction of carbon budget balance index and its application in the lake area

The imbalance of the carbon cycle in terrestrial ecosystems exacerbates global warming. Identifying the spatial–temporal characteristics and drivers of the carbon budget is important for the effective management of complex ecosystems and the achievement of the United Nations Sustainable Development Goals. Based on the complex ecosystem theory, this article constructs two carbon indicators, carbon carrying capacity–carbon footprint matching degree (Carbon-MD), and carbon carrying capacity–carbon footprint coupling coordination degree (Carbon-CCD). Taking a typical lake region—urban agglomeration around Poyang Lake as an example, the spatial–temporal characteristics and driving factors of the carbon budget from 2000 to 2020 are revealed by GIS technology and geographically–temporally weighted regression model. The results show that there is a significant spatial and temporal variability of carbon budget in Poyang Lake city agglomerations from 2000 to 2020, the Carbon-MD shows a gradually decreasing trend, and the Carbon-CCD shows a gradually increasing characteristic from moderate disorder to basic coordination development. From the spatial pattern, the Carbon-MD of the study area showed an increasing character from the core area to the peripheral area of the lake, and the low-value area of Carbon-MD shows the trend of spreading from point to surface and the Carbon-CCD changes from scattered to group type. In addition, land use type always has a significant effect on the carbon budget, while there is a spatial and temporal heterogeneity in the effects of natural and socioeconomic factors on the carbon budget. The research results show that it is reasonable and scientific to construct carbon budget indicators from the perspective of matching supply and demand and coupling and coordination, which provides a quantitative carbon budget analysis tool for local policymakers.

Quantifying the spatial nonstationary response of influencing factors on ecosystem health based on the geographical weighted regression (GWR) model: an example in Inner Mongolia, China, from 1995 to 2020

The identification of ecosystem health and its influencing factors is crucial to the sustainable management of ecosystems and ecosystem restoration. Although numerous studies on ecosystem health have been carried out from different perspectives, few studies have systematically investigated the spatiotemporal heterogeneity between ecosystem health and its influencing factors. Considering this gap, the spatial relationships between ecosystem health and its factors concerning climate, socioeconomic, and natural resource endowment at the county level were estimated based on a geographically weighted regression (GWR) model. The spatiotemporal distribution pattern and driving mechanism of ecosystem health were systematically analysed. The results showed the following: (1) the ecosystem health level in Inner Mongolia spatially increases from northwest to southeast, displaying notable global spatial autocorrelation and local spatial aggregation. (2) The factors influencing ecosystem health exhibit significant spatial heterogeneity. Annual average precipitation (AMP) and biodiversity (BI) are positively correlated with ecosystem health, and annual average temperature (AMT) and land use intensity (LUI) are estimated to be negatively correlated with ecosystem health. (3) Annual average precipitation (AMP) significantly improves ecosystem health, whereas annual average temperature (AMT) significantly worsens eco-health in the eastern and northern regions. LUI negatively impacts ecosystem health in western counties (such as Alxa, Ordos, and Baynnur). This study contributes to extending our understanding of ecosystem health depending on spatial scale and can inform decision-makers about how to control various influencing factors to improve the local ecology under local conditions. Finally, this study also proposes some relevant policy suggestions and provides effective ecosystem preservation and management support in Inner Mongolia.

Microcystin concentrations and congener composition in relation to environmental variables across 440 north-temperate and boreal lakes

Understanding the environmental conditions and taxa that promote the occurrence of cyanobacterial toxins is imperative for effective management of lake ecosystems. Herein, we modeled total microcystin presence and concentrations with a broad suite of environmental predictors and cyanobacteria community data collected across 440 Canadian lakes using standardized methods. We also conducted a focused analysis targeting 14 microcystin congeners across 190 lakes, to examine how abiotic and biotic factors influence their relative proportions. Microcystins were detected in 30 % of lakes, with the highest total concentrations occurring in the most eutrophic lakes located in ecozones of central Canada. The two most commonly detected congeners were MC-LR (61 % of lakes) and MC-LA (37 % of lakes), while 11 others were detected more sporadically across waterbodies. Congener diversity peaked in central Canada where cyanobacteria biomass was highest. Using a zero-altered hurdle model, the probability of detecting microcystin was best explained by increasing Microcystis biomass, Daphnia and cyclopoid biomass, soluble reactive phosphorus, pH and wind. Microcystin concentrations increased with the biomass of Microcystis and other less dominant cyanobacteria taxa, as well as total phosphorus, cyclopoid copepod biomass, dissolved inorganic carbon and water temperature. Collectively, these models accounted for 34 % and 70 % of the variability, respectively. Based on a multiple factor analysis of microcystin congeners, cyanobacteria community data, environmental and zooplankton data, we found that the relative abundance of most congeners varied according to trophic state and were related to a combination of cyanobacteria genera biomasses and environmental variables.

Progress in understanding the vulnerability of freshwater ecosystems.

The ability to collect and synthesize long-term environmental monitoring data is essential for the effective management of freshwater ecosystems. Progress has been made in assessment and monitoring approaches that have integrated routine monitoring programs into more holistic watershed-scale vulnerability assessments. While the concept of vulnerability assessment is well-defined for ecosystems, complementary and sometimes competing concepts of adaptive management, ecological integrity, and ecological condition complicate the communication of results to a broader audience. Here, we identify progress in freshwater assessments that can contribute to the identification and communication of freshwater vulnerability. We review novel methods that address common challenges associated with: 1) a lack of baseline information, 2) variability associated with a spatial context, and 3) the taxonomic sufficiency of biological indicators used to make inferences about ecological conditions. Innovation in methods and communication are discussed as a means to highlight meaningful cost-effective results that target policy towards heuristic ecosystem-management.

Local stakeholders’ priorities and perceptions towards forest ecosystem services in the Red panda habitat region of Nepal

The Red panda (Ailurus fulgens) habitat has been providing several ecosystem services (ES) to the people; however, the differences in local stakeholders’ perceptions and preferences of these ecosystem services based on differences in their location, caste, gender, age, and engagement in CFUG are still understudied. This study was conducted using a telephone interview with 120 households from 28 Red panda habitat districts in the Himalayan range of Nepal. Respondents were asked to: (1) prioritize and rank the environmental (regulatory ES), economic (provisional ES), social, cultural, and spiritual importance of the Red panda habitat areas; (2) identify and prioritize the provisional ES; and (3) share their perceptions about the current state of the forest and biodiversity in comparison to the past decade to assess the change in Red panda habitat condition. Key findings include: (1) gender, caste, location, and involvement in community forest had a significant influence on people's perception and preference for ecosystem services (p < 0.05); (2) in overall, the environmental value of forests was significantly prioritized over the social, cultural, and economic values (p < 0.05); (3) provisional services such as fuelwood and fodder were significantly prioritized by Dalit and indigenous people and CFUG members, whereas timber was given the highest priority by the Brahmin and Chhetri caste groups (p < 0.05); and (4) forest cover, biodiversity, and forest condition have significantly improved in East Nepal over the past 10 years, while the reverse was true in West Nepal (p < 0.05). Information on the preferences of local communities could assist in planning, policymaking, and effective management of natural ecosystems and ecosystem services. More importantly, the findings provide a better understanding of the nature–human interactions in the Red panda region and indicate that people from marginalized groups (ethnic communities, Dalit, and women) still rely on forests (community forests in many cases), and any consideration in future policies should take this into account.

Multi- and hyperspectral classification of soft-bottom intertidal vegetation using a spectral library for coastal biodiversity remote sensing

Monitoring biodiversity and how anthropogenic pressures impact this is critical, especially as anthropogenically driven climate change continues to affect all ecosystems. Intertidal areas are exposed to particularly high levels of pressures owing to increased population density in coastal areas. Traditional methods of monitoring intertidal areas do not provide datasets with full coverage in a cost-effective or timely manner, and so the use of remote sensing to monitor these areas is becoming more common. Monitoring of ecologically important monospecific habitats, such as seagrass beds, using remote sensing techniques is well documented. However, the ability for multispectral data to distinguish efficiently and accurately between classes of vegetation with similar pigment composition, such as seagrass and green algae, has proved difficult, often requiring hyperspectral data. A machine learning approach was used to differentiate between soft-bottom intertidal vegetation classes when exposed at low tide, comparing 6 different multi- and hyperspectral remote and in situ sensors. For the library of 366 spectra, collected across Northern Europe, high accuracy (>80%) was found across all spectral resolutions. While a higher spectral resolution resulted in higher accuracy, there was no discernible increase in accuracy above 10 spectral bands (95%: Sentinel-2 MSI sensor with a spatial resolution of 20 m). This work highlights the ability of multispectral sensors to discriminate intertidal vegetation types, while also showing the most important wavelengths for this discrimination (∼530 and ∼ 730 nm), giving recommendations for spectral ranges of future satellite missions. The ability for multispectral sensors to aid in accurate and rapid intertidal vegetation classification at the taxonomic resolution of classes, could be a significant contribution for future sustainable and effective ecosystem management.

The Trade-Offs and Synergies of Ecosystem Services in Pinus massoniana Lamb. Plantations in Guangxi, China

A scientific understanding of the synergistic and trade-off relationships among ecosystem services (ESs) is essential for maintaining the structure, function, and health of plantation forest ecosystems. This understanding facilitates effective ecosystem management practices, and helps identify the types, intensities, and spatial and temporal distribution characteristics of interactions among ESs, which is critical for regional development planning, ecological supplementation, and the maximization of economic benefits. In this study, we used correlation analysis, bivariate spatial autocorrelation, and hot spot analysis to comprehensively analyze the synergistic and trade-off relationships between ESs in Pinus massoniana (PM) plantations in Guangxi Paiyang Forest Farm from 2009 to 2018, across both time and space. The study showed that the ESs in PM plantations in Guangxi Paiyang Forest Farm maintained significant positive correlation (synergy), with a mutually reinforcing relationship among services. Notably, the regulating services shifted from weak synergy to weak trade-off relationships over time. From the bivariate spatial autocorrelation analysis, it is clear that the overall trade-off synergistic relationship among the four ESs is basically consistent with the correlation analysis results. From the distribution of multiple ES hot spots, we determined that the number of small groups that can provide three to four service hot spots in Guangxi Paiyangshan Forest Farm is greater. The spatial distribution of cold–hot spots of various ESs varied, and the distribution of cold–hot spots of supply services and regulation services of carbon sequestration and oxygen release was similar.

Plant communities regulated by water-level gradient in Caohai aquatic–terrestrial ecotones affect bacterial and fungal structures and co-occurrence networks

There is increasing awareness that vegetation dynamics play an important role in ecosystem stability and belowground microbial community diversity in wetlands. Studying plant–microbe dynamics and interactions under various conditions within lakes helps with the effective management of lake ecosystems by restoring ecosystem services. However, our knowledge about the response of microbial interactions to vegetation variation remains limited. We investigated how soil nutrients, enzyme activities, fungal and bacterial community diversity, and their network properties vary along the inundation gradient in aquatic–terrestrial ecotones of Caohai Lake in southwest China. Compared with the arid zone, the organic carbon and ammonia nitrogen contents in the severe inundation zone (SIZ) increased by 28.5% and 16.4%, respectively. Compared with the SIZ, the activities of cellobiohydrolase, β-1, 4-N-acetylglucosaminidase and leucine aminopeptidase in the dry–wet cycling zone increased significantly, increasing by 62.1%, 60.5% and 26.1%, respectively. Moreover, long inundation significantly reduced the abundance of fungi, diversity of bacteria, and size and complexity of their community co-occurrence networks. Microbial networks were smaller (fewer edges) and less stable (higher positive to negative edge ratios) in the SIZ. Aboveground vegetation regulated by water-level gradient can directly or indirectly affect microbial community structure and further interfere with the properties of bacterial and fungal co-occurrence networks. In conclusion, our findings suggested that plant communities regulated by water-level gradient play an important role in maintaining microbial diversity and co-occurrence network stability along the aquatic–terrestrial ecotone in Caohai Lake.

Combined Culture and DNA Metabarcoding Analysis of Cyanobacterial Community Structure in Response to Coral Reef Health Status in the South China Sea

Cyanobacteria occupy an extraordinarily diverse array of ecological niches in coral reefs because they play multifaceted roles, including primary carbon and nitrogen fixation, calcification, nutrient cycling, and oxygen production, as well as coral reef degradation through skeletal biocorrosion and polymicrobial diseases. In this study, cyanobacterial diversity in sediment, water, and coral tissues were explored in relation to coral health status (slightly, moderately, and severely damaged) of coral reefs at Weizhou Island, South China Sea. Microscopy of taxa morphological characteristics was combined with 16S rRNA gene metabarcoding. Fifteen and forty-three cyanobacterial genera were identified based on universal prokaryotic 16S rRNA gene primers and cyanobacteria-specific 16S rRNA gene primers metabarcoding, respectively, indicating a more sophisticated efficiency of the latter. In addition, three out of seven cyanobacterial strains that were isolated and identified based on morphology and phylogeny could not be detected using either molecular method. Therefore, culture-based combined cyanobacteria-specific 16S rRNA gene metabarcoding are highly recommended in future routine surveys. There was a clear distinction in cyanobacterial assemblage composition among locations with different coral health statuses, with degraded reefs exhibiting approximately a 1.25-fold increase in species compared to healthy habitats. In addition, the spreading of potentially toxic cyanobacteria, such as Nostoc and Lyngbya, in the degraded reef implies putative links to reef degradation. This study provides novel insights into the taxonomical diversity of cyanobacteria in tropical coral reefs. Metabarcoding is recommended as an effective tool for revealing cyanobacterial diversity patterns and thereby providing critical information for the effective management of coral reef ecosystems.

Incorporating circuit theory, complex networks, and carbon offsets into the multi-objective optimization of ecological networks: A case study on karst regions in China

Ecological networks (ENs) are important for maintaining regional ecological security and improving ecosystem service capacity. Therefore, it is important to consider spatial topological relationships and the need for carbon neutrality in the optimization of ENs. The optimization of EN structures and functions should be a systematic multi-objective process. This study combined landscape ecology, the complex network model, and spatial analysis technology, proposing an ecological barrier–topological feature–carbon offset-based (BTC-based) model research framework to deeply analyze and optimize ENs. First, the EN was preliminarily identified using the circuit theory model and the ecological barrier areas were simulated. Then, based on the complex network model, an undirected and unweighted complex network was established and its topological structural characteristics were analyzed. By constructing the estimation model for the carbon offset rate, its spatial distribution characteristics were calculated and interpreted. Finally, the BTC-based model was used to optimize the EN. Based on this model, Guizhou Province (a typical karst region in China) was taken as the research area for this study. The results showed that ecological improvement and degradation coexisted, and measures must be taken to optimize the EN. Based on the 2018 EN, the areas that required optimization were identified. Additionally, a restoration strategy was proposed for edge addition optimization for ecological corridors to promote the ecological protection and quality improvement of ecological sources and corridors. This approach would ensure the accurate implementation of ecological restoration projects and the effective management of ecosystems. The model proposed in this study also provides methodological support for EN optimization in other types of ecological regions.

An international assessment of the barriers influencing the effectiveness of island ecosystem management

Abstract Island ecosystems are disproportionally impacted by biodiversity loss and as such their effective management is critical to global conservation efforts. Practitioners world‐wide work to manage island sites and species to conserve them, but various day‐to‐day barriers compromise these efforts, reducing management effectiveness and preventing local and potentially even national biodiversity targets from being met. Identifying the most important barriers that currently impede effective island conservation could streamline investment to focus on cost‐efficient interventions that better reflect realities on the ground and the need to address barriers under substantial time and budget constraints. A survey of 360 practitioners working in island ecosystem management across 77 countries was conducted. The three most common barriers perceived by practitioners to prevent them from achieving more effective management are: low staff capacity; difficulties turning data into useful information for management (including lack of capacity and time to analyse data); and lack of a research and management strategy. Practitioners' perceptions of national‐level management effectiveness were mostly associated with their perception of governance issues, the presence/absence of research and management strategies and their experience of collaboration outcomes. Practitioners' experience of staffing and monitoring programme issues was important in shaping their perception of management effectiveness within the organisation(s) they worked with. Despite the indisputable need for transformative change to address the underlying causes of many of these barriers, more immediate and direct investment in strengthening the people and systems that are at the frontline of preventing biodiversity loss on islands is needed to bridge these barriers and achieve more effective management of island ecosystems. Read the free Plain Language Summary for this article on the Journal blog.

Impact of fisheries footprint on an early warning indicator of resilience reduction in marine net primary productivity

Abstract Human activities and climate change have profound effects on marine ecosystems, leading to changes in ecosystem functionality and even reduced resilience. Hence, a systematic assessment of the marine ecosystem resilience and the drivers of resilience is needed. This study provides an approach to help measure the resilience of reduction marine ecosystems by calculating early warning signs of marine net primary productivity, while introducing fishing activities and environmental data in the study area to evaluate the factors affecting marine ecosystem resilience. The results showed that in 36.29% of the Chinese exclusive economic zone, resilience was likely to be significantly decreased. There was a non-linear relationship between fishing activities and indicators of resilience reduction, with pixels with high-intensity fishing activities being more susceptible to resilience reduction. Fishing regulations are urgently needed in areas where marine ecosystem resilience may be reducing. Effective management and protection of marine ecosystems require assessment of the spatial overlap between marine ecosystems states and human activities. This study provides a scientific basis for sustainable management of social-ecological systems by comparing high-precision fishing data to marine environmental data, thereby analysing marine ecosystem resilience through the use of early warning indicators.

Assembly of non‐native fishes in North Patagonian streams: Species occurrence and abundance respond to different spatial scales

AbstractEcological communities are structured by combinations of biotic and abiotic factors acting at different spatial scales. However, the relative influence of the different scale‐related variables on assemblage composition is poorly understood, despite being key to the effective and efficient management of fluvial ecosystems. We took advantage of the relatively recent and well‐studied history of salmonid introductions in Patagonia to evaluate if non‐native species show different patterns of association with abiotic factors depending on the spatial scale of the environmental filter. We used a hierarchical approach to characterised environmental variables at the basin and reach scales to assess their influence on the presence, abundance and structure of the salmonid assemblages in breeding streams. We saw no evidence that presence/absence patterns of salmonid distribution were driven by landscape variables, except for those basins with physical environmental barriers to colonisation. However, we did find evidence for relative abundances being influenced by climatic and geomorphological variables (e.g., precipitation and relief). Our results do not support a scenario in which any of the salmonid species modulates the distribution of the other species, suggesting that interference has played only a minor role in determining current fish distribution in fluvial systems of the region. Instead, current patterns of presence and abundance of salmonids are best explained as the product of environmental filters. Our findings contribute to our understanding of the ecology of individual species and provide insight into the mechanisms structuring fish assemblages in Southern Hemisphere's lotic systems.

Investigating the trade-offs between the supply and demand for ecosystem services for regional spatial management

Understanding the supply and demand characteristics of ecosystem services (ESs) and their trade-offs is the basis for effective ecosystem management and the improvement of human well-being. However, current management practices based on the trade-offs between the supply and demand for ESs remain limited. This study aimed to integrate ES trade-offs into regional spatial management. With Changzhi, China, as the study area, this study evaluated the supply, demand, and trade-offs of food provision, water conservation, soil retention, and carbon sequestration by linking multi-source data and using spatial analysis tools, including the InVEST model, ArcGIS, and GeoDA. Based on the trade-offs and importance of different ecological functions, we constructed an urban spatial management framework and proposed recommendations for optimization in different management zones. The results showed that (1) the supply and demand for multiple ESs exhibited spatial heterogeneity. Except for water conservation, the supply of other ESs met the demand of the city, but there were still obvious deficits in some regions. (2) In terms of the ES supply, there were trade-offs between food production and other ESs, and synergies existed among water conservation, soil retention, and carbon sequestration. In terms of the ES demand, the four ESs exhibited synergistic relationships. In the cluster analysis, ES supply and demand were divided into four ES bundles, respectively. (3) The spatial mismatch of ESs in the sub-watersheds of the study area was obvious. The ESDR coldspots for the four ESs were primarily located in the urban built-up areas in the central and southern regions of the city. The ESDR hotspots of soil retention and carbon sequestration were mainly distributed in the eastern and northwestern regions of Changzhi, which are less urbanized. There were few ESDR hotspots for food production and water conservation. (4) Based on the regional spatial management framework, Changzhi was divided into ten zones, including extremely important, moderately important, important, supply–demand risk management, soil erosion management, and high food production areas. The results and conclusions of this study provide a basis for spatial planning and ecosystem management.

Spatial–Temporal Pattern and Influencing Factors of Vegetation Phenology and Net Primary Productivity in the Qilian Mountains of Northwest China

Understanding how vegetation growth responds to climate change is a critical requirement for predicting future ecosystem dynamics. Global warming causes significant changes in the vegetation characteristics of mountain ecosystems, particularly affecting vegetation phenology and net primary productivity (NPP). The Qilian Mountains are located in an arid and semiarid region, and the mechanisms of vegetation phenology in response to climate change still need to be further explored. We used MODIS data (2001–2020) to extract vegetation phenology and NPP, quantitatively evaluated their spatial–temporal dynamics, and analyzed the response mechanism of vegetation phenology–climate and vegetation phenology–NPP combined with meteorological data. The results showed that from southeast to northwest, the vegetation phenology changes significantly with the change in vegetation type, with SOS (start of the growing season) advancing at a rate of −0.415 d/year, EOS (end of the growing season) and LOS (length of the growing season) delaying at a rate of 0.20 d/year and 0.374 d/year, respectively, and NPP continues to increase. There was also an elevation gradient effect, with SOS delayed by 15.6 d/km, EOS advanced by 12.02 d/km and LOS shortened by 19.24 d/km. We found that the preseason temperature and SPEI (standardized precipitation evapotranspiration index) have a strong influence on the SOS and EOS, with the mean minimum temperature being the most significant and requiring attention, while the influence of precipitation cannot be ignored. We also found that the vegetation phenology is closely related to NPP, and SOS has the most significant effect. This study will provide a scientific basis for the response mechanisms of vegetation phenology in arid and semiarid regions under climate change. It will provide a reference for the implementation of effective ecosystem management.