Ecological Indicators最新文献

The universal contamination of arable land with potentially toxic elements (PTEs) poses a severe threat to food security and jeopardizes worldwide efforts to meet the United Nations Sustainable Development Goals (SDGs). How to obtain more reliable concentrations of PTEs in regional agricultural soils is a priority problem to be solved. Multispectral satellite remote sensing, with its advantages of high spatial and temporal resolution, broad coverage, and low cost, offers the potential to acquire spatial distribution of PTEs in agricultural soils over large areas. However, owing to the complexity of soil environments and the insufficiency of spectral information, the mechanism for retrieving concentrations of PTEs in agricultural soils via multispectral satellites is not yet clear, and the accuracy needs to be improved. In this study, we aimed to assess whether employing a fusion of spectral information and environmental covariates, results in more accurate retrievals of PTEs, specifically chromium (Cr) and mercury (Hg), in croplands than does employing spectral information alone. Three machine learning algorithms—kernel-based support vector machine (SVM), neural network-based back propagation neural network (BPNN), and tree-based extreme gradient boosting (XGBoost)—were developed to retrieve Cr and Hg concentrations in agricultural soils. The results showed that the fusion of spectral information and environmental covariates combined with the XGBoost model performed best in retrieving both Cr and Hg concentrations in agricultural soils with coefficient of determination (R²) values of 0.73 and 0.74, respectively. Environmental covariates were important variables for determining Cr and Hg concentrations in agricultural soils, but the ability to retrieve these element concentrations by utilizing spectral information alone was limited. High Cr concentrations occurred in central towns and southern hilly mountains. High Hg concentrations were detected in the northwestern region and southern hilly mountains. The potential of fusing spectral information and environmental covariates to precisely retrieve PTE concentrations in agricultural soils can serve as a reference for agricultural soil health information monitoring worldwide.

This paper investigates the response of mid-latitude montane peatlands to climate warming, focusing on changes occurring in a montane peat bog during a drought period. Unmanned Aerial Systems (UAS) equipped with multispectral and thermal sensors were used for high-resolution monitoring to analyze qualitative changes within the peat bog and their spatial distribution. The study was conducted in the Rokytka mountain peat bog in Šumava National Park, Czech Republic, which is one of the largest mountain peat bog complexes in Central Europe. Monitoring took place during the 2019 vegetation season, coinciding with the peak of the 2015–2019 drought. The recurrent UAS imaging campaigns were complemented by continuous hydrological and hydropedological monitoring and in-situ calibration measurements. The findings revealed diverging responses of montane peatlands to climate change across different functional zones of the peat bog. UAS thermal mapping identified distinct land surface temperature variations across various vegetation categories under different conditions. Notably, ponds and waterlogged areas displayed a stabilizing effect on land surface temperature variability, though they exhibited different absolute temperatures. In contrast, shallow waterlogged areas exhibited surface temperatures akin to dry open peat areas. Multispectral UAS monitoring demonstrated significant transitions among the peat bog zones in response to heat and drought propagation. The most pronounced changes occurred in shallow waterlogged areas, which shrank notably from 22.8% to 4.5%, while bare peat expanded from 26.8% to 45.5% during the 2019 drought season. High-resolution thermal and multispectral monitoring has revealed the scope and magnitude of the intra-peatland responses to drought and heat waves and serves as a sensible indicator of environmental changes of peatlands. It has disclosed a large cumulative effect of change in an environment composed of highly heterogeneous and subtle structures. The results highlighted the effectiveness of UAS monitoring in understanding the extent of change in montane peatlands as a fragile environment exposed to the effects of climate change.

Micro(nano)plastics (MNPs) are pervasive pollutants posing significant environmental and health risks. Selecting appropriate sentinel species to assess MNPs in terrestrial and aquatic environments involves considering factors such as species behavior, habitat, exposure pathways, and the feasibility of sampling. For these reasons, it was imperative to launch a virtual special issue (VSI) in Ecological Indicators. This editorial summarizes the contributions submitted to the VSI, which invited research on bioindicators of MNPs, including sampling protocols, monitoring strategies, and analytical methods, to advance our understanding and management of plastic pollution. The VSI received a total of 12 contributions from four countries, with a significant majority originating from Italy. To present the contributions, we have organized the sections into original articles and reviews. The original articles are further divided into sections on the occurrence of MNPs in biotic and abiotic compartments, the selection of bioindicators, and the effects and risk assessment of MPs. The reviews are categorized based on their focus on aquatic and terrestrial ecosystems. Future ecotoxicology studies should select bioindicators based on exposure to MNPs, conservation status, ecological roles, and human consumption.

Under the background of rapid urbanization, a series of urgent problems have emerged in China, such as tightening resource constraints and intensifying land use conflicts (LUCs). Based on the perspective of agricultural production – residents’ life – ecological security, this study took China as the study area, applied the multi-criteria evaluation analysis method to diagnose the LUC type based on spatial statistics, coupling relationship matrix, comprehensive conflict index, and spatial autocorrelation model, then divided the LUC risk changes into seven patterns, and analyzed their spatial evolution characteristics. The results demonstrated that the scale of competition for scarce land between agriculture, construction, and ecology increased by 3.4 % over the last 20-year period. High conflict zone was mainly located in the eastern plains, which was also the main distribution zone of agriculture-construction conflict, while the agriculture-ecology conflict zone was mainly located in the west. Over time, LUC risk grade changed in 14.3 % of the study area, with the largest area of transitions from no conflict to moderate conflict (34.78 %). High intensification zone coincided almost entirely with ecologically fragile regions of the Midwest, underscoring the critical importance of LUC perspectives in ecological conservation. We provided a new perspective for the study of LUC changes and a scientific reference for realizing sustainable land use management in China and other regions.

Understanding the coupling relationship between ecosystem service perceptions (ESP) and farmers’ well-being (FWB) in the ore-agriculture zone plays an important strategic role in maintaining regional ecological security and improving the well-being of regional farmers. Based on field research, questionnaire surveys and other methods, this study took farmers around the coal mining development zone as research subjects and used a comprehensive multi-index assessment method to evaluate the level of ESP and the FWB in the research area. A coupling coordination degree model was used to analyze the coupling relationship between ESP and FWB, and the random forest model was used to explore the influencing factors of the coupling relationship between the two. The results showed: (1) The FWB index was moderate and the ESP index was low. Farmers’ perceptions of the different ecosystem services varied, with provisioning services being perceived most strongly and supporting services least strongly. Satisfaction with basic material needs was highest on the well-being assessment. (2) The overall state of ESP and FWB coupling was good, with most of them in the state of coordination improvement. From the perspective of dimensional differentiation, the coupling of the dimensions of ESP and FWB was poorly coordinated, and all of them were in the state of dysfunction regression. (3) The coupling relationship between ESP and FWB was influenced by both environmental and household characteristics, with the former having a stronger effect. The results of this study can serve as a reference for promoting the coordination of ESP and FWB in the ore-agriculture zone, and ultimately realize the sustainable development of ecology and human in the ore-agriculture zone.

Zizania latifolia has been observed to generate floating mats due to water level fluctuations and wind-waves, leading to significant detrimental impacts on both water quality and biodiversity. The key to controlling and monitoring the spread and movement of Zizania floating is the early detection of outbreaks and the clarification of its formation mechanisms in response to water levels and wind actions. The temporal and spatial resolutions of conventional remote sensing monitoring methods are challenging to satisfy the requirements for continuous and accurate tracking of Zizania floating, which undergoes daily movement. This study develops a timely and accurate monitoring method for Zizania floating by calculating the Normalized Difference Vegetation Index (NDVI) from high spatiotemporal resolution PlanetScope (PS) imagery and building a decision tree on the Google Earth Engine (GEE) platform. Taking the Zizania floating outbreak in Honghu Wetland as the subject of our study, we extracted the continuous movement trajectories of Zizania floating from May to September 2019. Subsequently, we analyzed the interrelationship between the formation of Zizania floating and hydrometeorological factors. We then investigated the effects of Zizania floating on water quality and biodiversity. The results show that: (1) The integration of PS imagery and the GEE platform holds the potential to simplify the workload of remote sensing data processing. Based on the difference in NDVI between water bodies and Zizania floating, the dynamic expansion and reduction areas of the Zizania floating were successfully extracted by setting the threshold at 0.3, enabling timely and accurate tracking. (2) Abrupt fluctuations in water levels during brief time intervals serve as the primary trigger for Zizania floating. Additionally, wind speed during the same timeframe acts as a catalyst for the emergence of Zizania floating, with wind direction influencing its movement. (3) The outbreak of Zizania floating significantly elevates the concentrations of total nitrogen (TN), total phosphorus (TP), chemical oxygen demand (CODmn), and total ammonia nitrogen (TAN), while concurrently reducing the dissolved oxygen (DO) concentration in water bodies. The prolonged presence and movement of Zizania floating has reduced the biodiversity of the wetland ecosystem. Zizania floating mats present unique challenges due to their unpredictability, complicating the monitoring and tracking processes. It is necessary to develop a prompt, accurate, and cost-effective detection program for Zizania floating to reduce the risk it poses to wetland ecosystems.

The central areas of many Chinese cities have experienced large-scale urbanization in recent decades, a trend that is affecting the quality of life of residents and posing challenges to the sustainable development of urban ecosystems. Hence, it is vital to conduct assessments of urban ecosystems’ health conditions to ensure their sustainability. In this study, the spatial and temporal dynamics of ecosystem health in the central city of Wuhan were analyzed using the Vigor-Organization-Resilience-Service (VORS) model. The sensitivity of ecosystem health at different scales was also investigated using hierarchical health assessment delineation and random forest regression methods. The results showed that the composite index of ecosystem health has been declining since 2000, highlighting the negative impacts of shrinking ecological space, declining service capacity and urban expansion. Health zoning divides areas into five categories. Meanwhile, the health zones are located in areas of dense shrubs, cropland and water bodies on the edge of the central city, while the weak zones are mainly in the core of the city, which is 99.33 % impervious surface. The main factors influencing ecosystem health, including impervious surface area, water bodies and topography, vary from region to region. The study proposes targeted ecological management strategies for different health zones in Wuhan, emphasizing ecosystem protection and providing guidance for sustainable urban development.

Oases are vulnerable ecosystems that are affected by climate change. Using high-resolution climate models focusing on northern Africa, we investigate the changes in the agrosystems of oases. Projected air temperature changes under an extreme global warming scenario are statistically significant for all oases studied, with an increase of up to 4–4.5 °C by the end of the century. The impact of the projected warming is likely to lead to an increased groundwater demand, with a parallel trend in reduced precipitation. Combined, these processes endanger the long-term socio-economic prospect of oases.

Most studies have assessed and constructed landscape ecological security patterns (LESPs) primarily from the perspective of landscape morphology by employing morphological spatial pattern analysis, with little attention paid to fundamental ecosystem attributes (such as ecosystem functions and stability). Thus, this study proposed a comprehensive evaluation and optimization framework for LESPs from the perspective of “mode function stability” by integrating assessment landscape pattern, ecological function, and landscape stability. A comprehensive evaluation and optimization of the LESPs was conducted using the Minimum Cumulative Resistance (MCR) model in the Guanzhong Plain Urban Agglomeration (GPUA) as the research area. The results showed that: (1) Generally, the landscape quality in urban agglomerations was relatively low because of the large area of agricultural vegetation, high human interference, and landscape fragmentation, which caused low levels of landscape pattern, function, and stability. (2) LESPs were mainly determined by landscape stability in urban agglomerations due to low-quality ecosystems, rapid landscape transformation, and severe anthropogenic disturbances. (3) There was a large variation in the landscape function and stability of a certain landscape type due to their different structures and human interference across space in urban agglomerations. According to assessment by “pattern-function-stability” framework, the ecological sources and corridors covered with natural forest were the crucial cornerstone to constructing LESPs, and the rivers in crop planting areas were the inevitably selected corridors, but their ecological function and stability needed further improvement in construction. (4) The framework can assess spatial patterns and ecological functions to further the stability and sustainability of the landscape in maintaining ecological security and facilitating the identification of improvement objectives or measures of individual ecological sources or corridors in regional ecological infrastructure construction practices.

Microorganisms constitute the primary ecological group in desertified soil, driving soil biogeochemical cycles. Understanding their structure and diversity is crucial for the ecological restoration of desertification areas. This study focuses on the typical desert slopes in the eastern section of the northern foothills of the Tianshan Mountain in Xinjiang, China. It investigates changes in the main prokaryotic microbial community structure, including bacteria and archaea, and their relationship with environmental factors. Results show generally low soil water content, increasing with depth, and a weak alkaline nature with no significant vertical variations. While microbial communities do not distinctly respond to soil water content, there are noticeable variations in microbial diversity with clear stratification, negatively correlated with total organic carbon. Molecular ecological network analyses of five bare soil profiles in Xinjiang’s Hami Tianshan Desert reveal positive interactions among soil microorganisms in vertical layers. Surprisingly, the topsoil, despite having complex networks, shows low diversity and weak interconnectivity. Intriguingly, subsurface soils exhibit distinct molecular ecological networks similar to those found in ecological transition zones (These zones are characterized by rapid environmental shifts from one type to another), further highlighting significant ecological disparities between surface and subsurface soils. By analyzing the structure of soil microbial communities and their relationship with environmental factors on typical desert slopes in the Tianshan Mountains of Xinjiang, significant microbial ecological differences are found between surface and subsurface soils. Notably, in subsurface soils, microbial networks similar to those in ecological transition zones are discovered. These areas have complex microbial community structures and diverse ecological functions, providing new insights into the mechanisms of ecological restoration in desertified soils. Consequently, this study suggests that the vertical distribution patterns of microbial communities in bare desert soil areas differ from those in vegetated areas such as forests and grasslands. The interactions among species, the unique distribution of soil organic matter, and various physical factors are likely pivotal in the distribution patterns of microbial communities in bare desert soils. This research provides foundational theories and empirical support for the ecological restoration of bare desert soils.