Ecological Control Research Articles

Integrating land-sea coordination into construction of an ecological security pattern for urban agglomeration: a case study in the Guangdong-Hong Kong-Macao Greater Bay Area.

The construction of ecological security pattern (ESP) is of great scientific significance for solving the problem of habitat fragmentation in urban environment. However, previous studies mainly focused on the ESP in land area, leaving the sea area to be ignored. This study took the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) and its offshore area as an example and integrated the land-sea coordination into the construction of ESP based on the minimum resistance model, gravity model, and graph theory centrality. The results showed that there are 171 and 56 ecological sources for land area and offshore area, accounting for 31.46% and 21.51% of total area, respectively. Twenty-four important ecological corridors with a total length of 2738.05 km were identified in GBA, and the width is proposed to be less than 100 m. Moreover, the α, β, and γ index of the ecological network in the study area is 0.19, 1.33, and 0.5, respectively, indicating that the ecological network structure is complex and the connectivity between ecological nodes is good. The ecological restoration area includes 286.6 km2 of ecological pinch points and 140.44 km2 of ecological barrier. The overall ESP of the study area is "one ring, two belts, and four zones." The main body of the area with a superior ecological environment is distributed in a ring-like pattern near the outer edge of the study area, and two belts (important ecological corridor and ecological corridor) are distributed in a network. According to the ecological characteristics, the study area was divided into four zones: ecological preservation areas, ecological restoration areas, limited construction areas, and optimized construction areas. The ESP established herein institute provides a reference for the revision of ecological space control and optimization measures in the GBA. It also provides effective and systematic means to solve ecological problems in the current territorial spatial planning and territorial ecological restoration of coastal urban agglomeration.

A genomic view of environmental and life history controls on microbial nitrogen acquisition strategies.

Microorganisms have evolved diverse strategies to acquire the vital element nitrogen (N) from the environment. Ecological and physiological controls on the distribution of these strategies among microbes remain unclear. In this study, we examine the distribution of 10 major N acquisition strategies in taxonomically and metabolically diverse microbial genomes, including those from the Genomic Catalogue of Earth's Microbiomes dataset. We utilize a marker gene-based approach to assess relationships between N acquisition strategy prevalence and microbial life history strategies. Our results underscore energetic costs of assimilation as a broad control on strategy distribution. The most prevalent strategies arethe uptake of ammonium and simple amino acids, which have relatively low energetic costs, while energy-intensive biological nitrogen fixation is the least common. Deviations from the energy-based framework include the higher-than-expected prevalence of the assimilatory pathway for chitin, a large organic polymer. Energy availability is also important, with aerobic chemoorganotrophs and oxygenic phototrophs notably possessing ~2-fold higher numbers of total strategies compared to anaerobic microbes. Environmental controls are evidenced by the enrichment of inorganic N assimilation strategies among free-living taxa compared to host-associated taxa. Physiological constraints such as pathway incompatibility add complexity to N acquisition strategy distributions. Finally, we discuss the necessity for microbially-relevant spatiotemporal environmental metadata for improving mechanistic and prediction-oriented analyses of genomic data.

Impacts of atmospheric air pollution on the cities of the Navoi region

The president of the Republic of Uzbekistan, Shavkat Mirziyoev, in his address to the Oliy Majlis in 2021, said that, we must pay more attention to environmental protection and improvement of the ecological situation. They emphasized that it is necessary to improve the system of ecological control of the production process and to develop a comprehensive program of measures designed until 2025 to prevent the impact of industrial development on the environment. The rapid growth of cities, the intensification of urbanization processes that lead to all socio‐ecological consequences, and the accumulation of large sources of anthropogenic impact on the surrounding area make cities the main object of study. The relevance and social importance of the study of the urban environment contribute to the involvement of many scientific disciplines in the development of their research concepts and directions for the optimization of the living environment of urban residents. The diversity of research calls for the synthesis of ecological knowledge about the city. Economic and social geography is a science capable of realizing the potential of integration in the study of such a complex object. The city should operate in the environment of the area with ecological balance, which ensures the sustainable and harmonious development of the area and the city. The reproduction of the main components of the natural environment and preservation of the diversity of geosystems can be achieved by harmoniously incorporating them into the regional natural ecological system, taking into account the natural and socio‐economic characteristics of the city. In general, much work has been done in economic and social geography in the study of the city and its surrounding areas. In the course of the development of agglomerations, the study of the interaction between the city and the region, migration and labour flows is of great practical importance and has helped to solve many important national economic and socio‐economic problems. In economic and social geography, many works in the ecological direction are devoted to the impact of cities on the environment, the impact on environmental components, the organization of the territory, etc. However, the reverse chain of the “territory‐urban environment‐city” relationship has hardly been analyzed in research. The choice of the territory of the Navoi region is symbolic because the region has a large industrial potential and is distinguished by highly intensive agriculture. Various problems in the area can be summarized in 3 blocks: improvement of economic activity, improvement of territorial structure and urban planning structure, protection and optimization of environmental quality. The most important criterion that reflects the range of negative effects of the quality of the environment is the health of the population. However, caution should be exercised when interpreting these indicators and using them in conjunction with other criteria. This article describes some of the results and conclusions of the research conducted on the indicators of atmospheric air pollution in the cities of the Navoi region and their negative consequences.

Effect of agricultural landscape pattern on the qualitative food web of epigaeic arthropods in low hilly areas of northern China

Under the macro background of global change and sustainable development, the sustainable and healthy development of agricultural landscapes is crucial for human well-being. Formulating targeted protection measures based on biodiversity conservation is currently a hot topic and challenge. Our study focused on Jianping County, a typical hilly area in northern China, to understand the impact of regional agricultural landscape patterns on qualitative food webs. We calculated food web parameters by constructing predator-pest qualitative food web matrices and compared the differences in food web structure characteristics under different agricultural landscape patterns. By using function regression method, we established landscape indices and food web parameter models. The results showed that the average number and community structure of predatory natural enemies and pests varied across different agricultural landscape patterns, but the common groups were similar. Maintaining a proportion of 30–40 % non-crop habitats is optimal for the stability of qualitative food webs. Different landscape elements have varying regulatory effects on the structure of qualitative food webs, and the food web parameter model can explain these effects more directly. Specifically, the Landscape Shape Index (LSI) is significantly positively correlated with Generality (G), while the Contagion Index (CONTAG) is significantly negatively correlated with vulnerability (V). We propose that in low hilly areas, where non-crop diversity is the primary source of heterogeneity, promoting measures for non-crop habitats through landscape planning will help maintain the richness of epigaeic arthropods and the stability of qualitative food webs. This research is of great significance in promoting ecological control and sustainable development of agroecosystems in low hilly areas.

Cover Caption

AbstractThe Asian longhorn beetle (ALB), Anoplophora glabripennis, is considered one of the most successful and feared invasive insect species globally. In recent decades, extensive research on ALB has captured the attention of scientists worldwide, leading to investigations into various aspects of its biology and strategies for control and management. These comprehensive explorations have been widely reviewed in China (see pages 1534–1551). Specifically, the ecological control of ALB involves planting mixtures of preferred and resistant tree species, which has proven effective in preventing outbreaks. The cover photo depicts an ALB adult feeding on Elaeagnus angustifolia, a type of dead‐end trap tree for ALB. Photo provided by Lixiang Wang.

Study of the collaborative prevention and control mechanisms of ecological and environmental risks in China's Yangtze River Economic Belt.

The Yangtze River Economic Belt, as a globally important economic growth pole and population concentration area, has always received attention to its ecological and environmental issues. Currently, there is little research on the synergy among the ecological environment risk prevention and control mechanisms in this region. Strengthening research in this area has important scientific value for improving the effectiveness of ecological risk prevention and control and the sustainable development of the Yangtze River Economic Belt. Based on the data from 11 provinces and cities in the Yangtze River Economic Belt from 2017 to 2021, this study establishes an indicator system with benefit incentive mechanisms, risk regulatory mechanisms, and risk governance mechanisms as frameworks. By employing a composite system synergy model, this study utilizes the entropy weight method to assign weights to each indicator and calculates the orderliness and synergy of the three mechanisms separately. The results show that: (1) There are differences in the orderliness of mechanisms among the regions. The downstream area has the highest orderliness of the three mechanisms, with the middle stream area higher than the upstream area in terms of incentive mechanisms and risk governance mechanisms. (2) The orderliness of each mechanism has slight fluctuations but shows an overall upward trend, with the orderliness of regulatory mechanisms significantly higher than that of incentive mechanisms and governance mechanisms. (3) In terms of synergy, the three major mechanisms show a stable upward trend in synergy but with a relatively low degree of synergy. Based on these findings, future efforts should focus on optimizing mechanism construction and information sharing, improving incentive mechanisms, strengthening risk regulatory mechanisms, and consolidating the effectiveness of risk governance mechanisms.

Prediction of phytoplankton biomass and identification of key influencing factors using interpretable machine learning models

The water quality of the Middle Route of the South-to-North Water Diversion Project (MRP) of China is related to the health and safety of about 8500w people. In recent years, multiple occurrences of abnormal algal proliferation in water conveyance channels have posed potential risks to the water quality of diverted water. To clarify the growth situation of phytoplankton and evaluate the response relationships between water environmental parameters and phytoplankton in the MRP, in this study, a long-term monitoring dataset was collected from seven monitoring sites from May 2015 to December 2020 to statistically analyse the spatiotemporal characteristics of planktonic algal cell density (ACD). Based on this, four machine learning models, including multiple linear regression (MLR), support vector regression (SVR), random forest (RF), and extreme gradient boosting (XBGoost), were constructed to predict the ACD, and the SHapely Additive exPlanations (SHAP) method was used to interpret the best prediction model for identifying the response relationship between water environmental parameters and ACD. The results showed that (1) the seven monitoring sites could be divided into two significant groups (i.e., Group I and Group II) by hierarchical clustering analysis (HCA), among which the ACD of Group II was higher than that of Group I. (2) the performance of four prediction models using different evaluation metrics indicated that the RF model surpassed in prediction accuracy compared with the other three models in predicting ACD variations in Group I and Group II. (3) SHAP analysis revealed that the key factors affecting ACD variations in Group I were water temperature (WT), water depth (WD), permanganate index (PI), flow rate (Q) and dissolved oxygen (DO), and the ACD were inhibited when WT was below 23 °C, WD exceeded 6.5 m, and Q was between 100 and 250 m3/s. Additionally, WT, PI, and DO were the most important predictors of ACD in Group II, and ACD were inhibited when WT was below 24 °C, PI was lower than 2.4 mg/L and DO was higher than 9 mg/L. This research provides a theoretical basis and reference for water quality management and algal ecological control of water transfer projects with high spatial heterogeneity.

Rhizosphere microbial ecological characteristics of strawberry root rot.

Strawberry (Fragaria × ananassa Duch.) holds a preeminent position among small fruits globally due to its delectable fruits and significant economic value. However, strawberry cultivation is hampered by various plant diseases, hindering the sustainable development of the strawberry industry. The occurrence of plant diseases is closely linked to imbalance in rhizosphere microbial community structure. In the present study, a systematic analysis of the differences and correlations among non-culturable microorganisms, cultivable microbial communities, and soil nutrients in rhizosphere soil, root surface soil, and non-rhizosphere soil of healthy and diseased strawberry plants affected by root rot was conducted. The goal was to explore the relationship between strawberry root rot occurrence and rhizosphere microbial community structure. According to the results, strawberry root rot altered microbial community diversity, influenced fungal community composition in strawberry roots, reduced microbial interaction network stability, and enriched more endophytic-phytopathogenic bacteria and saprophytic bacteria. In addition, the number of bacteria isolated from the root surface soil of diseased plants was significantly higher than that of healthy plants. In summary, the diseased strawberry plants changed microbial community diversity, fungal species composition, and enriched functional microorganisms significantly, in addition to reshaping the microbial co-occurrence network. The results provide a theoretical basis for revealing the microecological mechanism of strawberry root rot and the ecological prevention and control of strawberry root rot from a microbial ecology perspective.

Low Genetic Diversity of the Only Clade of the Tick Rhipicephalus microplus in the Neotropics.

This study addresses the variability of the mitochondrial cytochrome oxidase subunit I (COI) and 16S rDNA (16S), and nuclear internal transcriber spacer ITS2 (ITS2) genes in a set of field-collected samples of the cattle tick, Rhipicephalus microplus (Canestrini, 1888), and in geo-referenced sequences obtained from GenBank. Since the tick is currently considered to be a complex of cryptic taxa in several regions of the world, the main aims of the study are (i) to provide evidence of the clades of the tick present in the Neotropics, (ii) to explore if there is an effect of climate traits on the divergence rates of the target genes, and (iii) to check for a relationship between geographical and genetic distance among populations (the closest, the most similar, meaning for slow spread). We included published sequences of Rhipicephalus annulatus (Nearctic, Afrotropical, and Mediterranean) and R. microplus (Afrotropical, Indomalayan) to fully characterize the Neotropical populations (total: 74 16S, 44 COI, and 49 ITS2 sequences included in the analysis). Only the clade A of R. microplus spread in the Nearctic-Neotropics. Both the K and Lambda's statistics, two measures of phylogenetic signal, support low divergence rates of the tested genes in populations of R. microplus in the Neotropics. These tests demonstrate that genetic diversity of the continental populations does not correlate either with the geographic distance among samples or with environmental variables. The low variability of these genes may be due to a combination of factors like (i) the recent introduction of the tick in the Neotropics, (ii) a large, effective, and fast exchange of populations, and (iii) a low effect of climate on the evolution rates of the target genes. These results have implications for the ecological studies and control of cattle tick infestations.

Let there be light to interact

Light plays a crucial role in ecological dynamics, both as a consumable resource and as an environmental factor. Prokaryotic and eukaryotic photoautotrophs use light as an energy source for photosynthesis, which forms the basis of food chains and determines the flow of energy and matter in ecosystems. Light availability and quality can influence resource complementarity and species coexistence, as well as the stoichiometry of primary producers and the transfer efficiency of food webs. In addition, light serves as an important source of information for organisms, influencing their activities and interactions with the environment. Light shapes biotic interactions, including competition, predator-prey relationships, and mutualistic and antagonistic relationships between photoautotrophs and heterotrophs. Anthropogenic activities affect these photoecological processes, with largely unknown consequences. Hence, understanding the ecological role and control of light is essential for understanding the functioning of ecosystems and biogeochemical cycles.

A hierarchical optimization strategy in the intelligent ecological control of the greenhouse downy mildew

In a low-cost greenhouse, where there are few actuators to regulate the climate, increasing yield and preventing crop diseases are contradictory processes because pathogens and hosts stay in a similar ecological niche. Under given weather conditions, the environmental range for crop growth and disease control must be carefully balanced. The aim of this paper is to develop an accurate optimal control algorithm for disease ecological control and explore its contribution in the application of intelligent downy mildew prevention in a low-cost solar greenhouse. The proposed hierarchical optimization control strategy is compared with four common management methods in order to evaluate its impact on crop growth and disease prevention. The results show that the hierarchical optimization control strategy reaches the best balance between disease prevention, accumulated temperature promotion, and low temperature stress risk reduction without using an additional heating system. Moreover, an event-based PID controller is applied to the system considering the energy conservation aspect, which decreases the vents movements areas by 16%, while the control error is only increased by 1.9%. On the whole, this paper provides a solution for low-cost greenhouses about the joint use of greenhouse modelling, disease early warning and environment control, looking for promoting the green production in greenhouse environments by considerably reducing the disease occurrence and use of pesticides.

Digital research on the resilience control of water ecological space under the concept of urban-water coupling

Introduction: The construction of digital governance of national land space depends greatly on the development of a digital model for robust control of water and ecological space. However, how changes to the urban-water coupling relationships affect the resilience control of water ecological space is rarely reported.Methods: The evolution characteristics of urban and water space in the study area from 2000 to 2020 and the correlation between them are analyzed based on the grid analysis using InVEST and Moran’I methods. Based on the theory of human-environment interaction territorial system to provide a theoretical framework to explain the urban and water space. We used digital to construct an resilience control framework in the Dongting Lake area based on the correlation between the urban and water space.Results: The results show that: 1) From 2000 to 2020, the geographical evolution of towns and cities in the research area displayed obvious spatial variation in intensity, indicating a process of expansion and change. The regional and temporal fluctuations of the water conservation function are significant. The mountainous areas in the east, south, and northwest are where the high values of the water conservation function are primarily found. These regions have more vegetation, which increases the water conservation function. 2) According to the results of local binary spatial autocorrelation analysis, it can be seen that from 2000 to 2020, the high-high agglomeration of town space and water-related is mainly distributed in Linxiang City, Yueyang County, Miluo City, Li County, and Yiyang City, and the low-low agglomeration is mainly distributed in Dongting Lake, Datong Lake, and along the Yangtze River. 3) Based on how urban spatial evolution affects water ecological space, we construct a theoretical framework of urban-water coupling and establish a digital model of water ecological space resilience control in the Dongting Lake area from four perspectives: threshold, visualization, dynamics, and intelligence.

Variation Analysis of Long-term TN concentration and influencing factors in Miyun Reservoir in China

<p>The total nitrogen (TN) is the key indicator for the eutrophication of Miyun Reservoir. Base on the long-term series of remote sensing, hydrological and water quality observation data, this paper comprehensively analyzed the trend of water quality especially the TN concentration and its influencing factors over 30 years in Miyun reservoir. The development trends of the TN concentration during the 14th Five Year Plan Period were predicate with the designed water quality scenarios simulations. The results showed that the water covered area of Miyun reservoir was reduced from 1986 to 2004 and enlarged from 2004 to 2020, and the smallest water covered area was about 56.4km2 in 2004 while the largest was about 170.7km2 in 2020. For the regional rainfall and artificial water storage, the inflow of Miyun reservoir is much greater than the water intake, and this is the main reason for the water covered area increased. From 1988 to 2020, TN contents in the inflow water of Chaohe river and Baihe river were generally in upward trends, with annual upward rates of 0.16 mg/L and 0.05 mg/L at the 99% confidence levels separately. However, the TN concentrations from Chaohe river and Baihe river presented downward trends for the recent 5 years. And this is own to the emission control and river ecological control measures in the upstream basin of Miyun reservoir. From 1988 to 2020, the annual averaged TN concentration of the main dams in Chaohe and Baihe (BHZB and CHZB) was 1.10±0.32 mg/L and 1.17±0.31 mg/L respectively and in recent 5 years, and significant positive trends were also identified at both two stations with the steadily rising the water level and volume in Miyun reservoir. The lightly increase of TN concentration in recent years in Miyun reservoir was the comprehensive results of external input and self purification capacity. Based on the MIKE21 model of four scenario simulations, the TN concentration of Miyun reservoir will meet the class Ⅱ water quality level (China’s Environmental Quality Standards for Surface Waters, GB3838-2002) under the comprehensive implementation of rural domestic source control and agricultural non-point emission control measures in the upstream basin of Miyun reservoir during the 14th Five Year Plan period.</p>

Study the Impact of Plateau Pika Activity on the Ecological Dynamics of the Qinghai-Tibet Plateau

The Tibetan Plateau, the world's largest plateau, harbors diverse ecosystems that play vital roles in the global environment. This study aims to investigate the ecological impact of the plateau pika, an endemic species, on the plateau's water resources, carbon storage, biodiversity, and climate. The research advocates for a balanced approach to pika control, emphasizing ecological preservation while addressing the associated challenges. Various statistical tests were employed to quantify the relationship between plateau pika activity and ecological dynamics. Correlation analysis revealed a significant negative correlation between pika burrow density and soil moisture content. T-tests demonstrated a significant difference in soil carbon content between areas with high and low pika burrow densities. A chi-squared test found no significant association between pika population density and the presence of vulnerable species. Ecological protection and sustainable development are crucial, with plant-based pesticides like ricin offering an effective and environmentally friendly means of pika control. However, ecological restoration should be the core of rodent control efforts to maintain a balanced ecosystem. Combining grazing policies with ecological grassland control measures can help mitigate rodent damage while improving grassland productivity.

A review and uncertainty analysis of Lake Urmia's hypsometric relationships

Lake Urmia, once the second-largest saline lake worldwide, has almost dried. Several studies have provided bathymetric maps for the lake using different data and techniques but rarely identified the associated uncertainties. This paper provides a comprehensive review of Lake Urmia bathymetric studies and discusses the underlying uncertainties. We developed an updated hybrid bathymetry and hypsometric relationships for Lake Urmia using in-situ and satellite data. The proposed hybrid bathymetry was validated against independent in-situ depth data (with an RMSE < 20 cm) and applied as a baseline for comparison with other available bathymetry models. Results revealed that uncertainties in lake depth measurement, water delineation algorithms from satellite data, spatial interpolation method, and sensor resolution have the highest uncertainty, respectively. Furthermore, the width of the uncertainty bands in the lake level-area relationships is not uniform and peaks at lake levels between 1270 and 1272 m, which are critical for conserving crucial ecosystem services of Lake Urmia, such as island conservation and dust control. Our synthesis indicated that the application of various Lake Urmia bathymetries could lead to about 0.5 and 1 km3differences in the estimated lake volumes for obtaining the ecological and dust control levels, respectively. Our findings provide useful insights for Lake Urmia managers, also applicable for other saline lakes, into considering thedynamic of lake topography and associated uncertainties in lake conservation/restoration programs.

Multi-Dimensional Collaborative Operation Model and Evaluation of Cascade Reservoirs in the Middle Reaches of the Yellow River

Reservoir operation optimization is a technical measure for flood control and is beneficial owing to its reasonable and reliable control and application of existing water conservancy and hydropower hubs, while ensuring dam safety and flood control, as well as the normal operation of power supply and water supply. Considering the beneficial functions of reservoirs, namely flood control and ecological protection, this paper firstly established a two-objective optimal operation model for the reservoir group in the middle reaches of the Yellow River. We aim to maximize the average output of the cascade reservoir group and minimize the average change in ecological flow during the operation period under efficient sediment transport conditions, with the coordination degree of water and sediment as the constraints of reservoir discharge flows. The paper aims to construct an evaluation index system for reservoir operation schemes, apply a combined approach of objective and subjective evaluations, and introduce the gray target and cumulative prospect theories. By uniformly quantifying the established scheme evaluation index system, screening the reservoir operation schemes with the fuzzy evaluation method, and selecting the recommended scheme for each typical year, this paper provides a new scientific formulation of the operation schemes of reservoirs in the middle reaches of the Yellow River. The selected schemes are compared with actual data, demonstrating the effectiveness of joint reservoir operation and for multidimensional benefits in terms of power generation, ecology, and flood control.

Functional and temporal facets of predation by marsh frogs across the aquatic–terrestrial ecotone of ponds and implications in the context of biological invasions

Abstract Freshwater vertebrate predators can exert trophic control over aquatic and littoral communities. Among these predators, post‐metamorphic anurans exhibit a biphasic trophic spectrum by foraging in both terrestrial and aquatic habitats. Many studies have described their diet through the classical taxonomic classification of prey. However, these singular diet habits imply a complex, time‐dependent, realised trophic niche in which predation pressure occurs over many consumers that fill diverse functional roles throughout the aquatic and terrestrial interface of ponds. Among anurans, marsh frogs (Pelophylax ridibundus) have been introduced outside their range in many countries and are now invading nationwide areas, particularly in western Europe. Focusing on their foraging specificities will therefore further the understanding of the trophic role of these alien taxa in pond environments that are highly colonised. We collected stomach contents from 761 marsh frogs from introduced populations in 19 ponds in southern France once a month over 4 months of their active period in the spring. The populations of marsh frogs were studied in a geographic area that was devoid of native water frogs and their origin tracks back as far as south‐eastern Europe (i.e., more than 1,000 km from the studied sites, as evidenced previously by genetic analyses). Marsh frogs exhibited generalist and opportunistic feeding strategies. The trophic niche was strongly asymmetrical and broader in the terrestrial environment than in the aquatic environment. However, predation occurred in communities of large freshwater macroinvertebrates and amphibians. Whereas the composition of the terrestrial diet exhibited strong seasonal variations, predation pressure was continuously exerted on the same aquatic organisms over time. Primary consumers and consumers at higher trophic levels frequenting aquatic benthic, vegetated, pelagic, and surface microhabitats were preyed upon, underlying the multidimensional extent of the predation spectrum. The diversified feeding strategies of alien marsh frogs highlight the extent of potential ecological control by predation on pond communities. Because of their wide trophic niche, they exert predation pressure on most pond organisms, triggering possible top‐down control of the overall aquatic communities. Our results show that the integration of the functional traits and microhabitats of consumed prey may aid in a better understanding of how predation by anurans may target specific components of pond communities. More particularly, this study raises concerns about the predatory role of introduced anurans in the context of biological invasions.

Regional ecological risk assessment based on multi-scenario simulation of land use changes and ecosystem service values in Inner Mongolia, China

Regional ecological risk assessment (ERA) is an important means towards sustainable regional development. Yet, existing ERA approaches often fall short of characterizing ecological processes as dynamic processes involving uncertainty. Using Inner Mongolia, a high ecological risk area in China, this study employed a framework for regional ERA that considers ecosystem service value (ESV) and four scenarios of future land use patterns to understand its regional ecological risk. The spatially explicit risk assessment method was implemented by a model combining multi-criteria evaluation (MCE), cellular automata (CA), and Markov chain to predict future land use/cover of 2030, an adjustment-based equivalence factor method to assess the ESV in each scenario, and Sharpe Index to assess regional ecological risk. The results show the following. First, the overall ESV increases from 2020 to 2030 under all but the socio-economic development (SED) scenarios considered in this study. Second, the overall regional ecological risk of Inner Mongolia is high in the central region and low in the east, north, and west regions. The low ecological risk areas account for the largest areal proportion in the ecosystem services protection (ESP) and natural development (ND) scenarios, while the medium ecological risk areas are the largest under SED. However, some low ecological risk areas are converted into medium ecological risk in ecological and socioeconomic balance scenario (ESB) scenario. Third, NDVI is the driving factor with the strongest explanatory power for the regional ecological risk in Inner Mongolia, followed by mean annual precipitation and temperature. The present study applied a framework for regional ERA that explicitly considers spatial heterogeneity and uncertainty, which can be useful for guiding decision-making for ecological risk control and the planning of the land use of ecosystems.

Field practice of Scirpus mariqueter restoration in the bird habitats of Chongming Dongtan Wetland, China

The coastal saltmarshes in China have been seriously degraded and artificial restoration strategies have become one of the primary measures to protect the coastal habitats. In this study, we investigated efficient restoration techniques for native saltmarsh plants in vacant habitats within the project area of the Ecological Control of Spartina alterniflora and Improvement of Birds Habitats in the Shanghai Chongming Dongtan Bird National Nature Reserve in the Yangtze Estuary. Through field and pilot experiments, we analyzed the effects of propagule types and transplanting methods on the restoration efficiency of Scirpus mariqueter, a dominant saltmarsh species in the Yangtze Estuary. We further evaluated the cost and efficiency of various restoration strategies. Our results indicated that: 1) The corm seedlings of S. mariqueter had higher flood tolerance, and were suitable for use in the habitats with higher environmental heterogeneity. 2) Across the four treatments for S. mariqueter restoration, the most economically efficient treatment was to transplant low-density corm seedlings without sediment, with an investment cost of approximately ￥10100 per hectare. The costs were ￥41100, ￥30000, and ￥120100 per hectare for high-density without sediment, low-density with sediment, and high-density with sediment restoration, respectively. 3) After nearly 5-yr efforts, the S. mariqueter community of Plot C3 in project area had achieved a coverage of over 60%, marking a relatively successful large-scale field restoration. This study could provide the foundation and support for large-scale coastal saltmarsh restoration projects.

Comparative study on community structural diversity of pests in pomelo orchard with different management modes

In order to learn the community structural diversity of pests and temporal dynamics in different management modes of pomelo orchard, we selected abandoned pomelo orchard (AM) and traditional pomelo orchard (TM) to investigate the characteristics of pest community structure by netting, observation and sticky board trapping methods and classified and identified through the methods of morphology and molecular biology from May to October in 2020. The results showed that the amount of species was larger in AM orchard, while the individuals of pests were less than those in the TM orchard.The values of Margalef's index, Shannon-wiener index and Pielou index were all showed bigger in TM than those in AM, while the Simpson index was smaller, all of which with significant differences (P&lt;0.05). The absolute advantage insects were Dacus dorsalis (19.75%), Dialeurodes citri (13.28%) and Lucilia sericata (10.15%) in TM orchard and Dacus dorsalis (75.87%) and Rhynchocoris humeralis (14.51%) in AM orchard. There was significant difference between the two community relative stability indexes (P&lt;0.05). The similarity index of insect communities in both orchards was in the range of 0.18 to 0.40, which indicated moderately dissimilar to extremely dissimilar. The richness, diversity and evenness of insect community in TM orchard were bigger than those in AM orchard, which demonstrated that the ecological environment was more stable with more reasonable insect community structure and less particularly advantageous pest occurrences. This also indicated that it is important to utilize scientific management measures to create a harmonious and stable ecological environment, maintain appropriate diversity of ground cover plants, avoid abuse of chemical pesticides, build pest populations at reasonable thresholds and achieve the goal of improving quality of fruits and increasing income for planters. Keywords: Vegetation, Pests, community structure, diversity, ecological control.