Search

International audience; Urbanization is one of the main causes of land use change, especially from 1990 to now in China, but knowledge of its effect on different functional groups of carabids and spiders in the adjacent rural areas over time remains limited. We assessed whether landscape alterations (1993 versus 2013) drove changes in carabid and spider functional groups (1995 versus 2013) in an agricultural landscape located on the fringe of a rapidly growing city in China. Although built-up land increased from 6.3% to 32% across the whole landscape, the overall species richness of carabids and spiders did not decline. In contrast to the reduction in species richness of large carabids, the species richness of small carabids increased. Species richness of both large and small spiders increased. The species composition of carabids and spiders significantly changed between 1995 and 2013. Species compositions of large, predatory carabids and large or ground-hunting spiders were more sensitive to the changes in built-up land than those of small, omnivorous carabids and small or web-building spiders. The amount of grassland (abandoned land covered by wild grass) also increased as farmers began to work in the city. The increased grassland significantly contributed to the increased species richness of predatory and macropterous carabids. However, increased landscape diversity did not affect species richness of either carabids or spiders. High landscape diversity was related to reduction in field size, resulting in a decrease in the mean body size of carabids. This indicates that evaluating the effect of landscape change on carabid and spider diversity should be based on their functional traits. Different taxa, even different functional groups, have different responses to landscape change. The increase in built-up land did not immediately reduce species richness at the urban fringe. Increasing wild grasslands and combining smaller fields may benefit farmland biodiversity in this region.

Wild bees provide important pollination services for crops and wild plants. While land use intensification has resulted in steep declines of wild bee diversity across agricultural landscapes, the creation of semi-natural habitats has been proposed as a counter-measure. However, the relative value of semi-natural and natural habitats in promoting wild bees has rarely been studied, especially for China that harbors the world's largest plantation forest area, characterized by intensively managed, mono-dominant stands of wind-pollinated tree species. We sampled wild bees in apple orchards to assess how their assemblages were influenced by semi-natural habitats in the surrounding landscape and the local flowering ground-cover. Bee abundance declined with increasing isolation from natural shrubland. In contrast, wild bee diversity and abundance were negatively linked to plantation forests. For the abundance of large bees, this effect was partly ameliorated by local flowering ground-cover. Maintaining or restoring wild bee assemblages in agricultural landscapes therefore requires careful evaluations of restoration measures such as forest planting. Availability of local flower resources and nearby natural shrubland appeared particularly important to enhance wild bees and their potential services in apple orchards.

Several studies have documented the semi-natural habitats and heterogeneous landscape patterns play a crucial role in maintaining spider diversity in agricultural landscapes. However, which types of semi-natural habitat contribute more to conserve spider diversity and functional traits, and how they respond to landscape patterns at different landscape scales are still poorly understood. Thereby, we sampled epigeic spider communities by pitfall traps within recovered grasslands, plantation forests and croplands around three villages with different altitudes in northern China and surveyed the surrounding landscape structures in both 2017 and 2018. The results confirmed the diverse distribution of spiders in different habitat types. There was a greater spider activity density in recovered grasslands than that of plantation forests or croplands significantly. Furthermore, both recovered grasslands and plantation forests contained more species richness than croplands. Moreover, the spider community in the recovered grasslands and cropland had more similar functional trait compositions (including hunting types, body size and ballooning ability) comparing to the plantation forests, which mainly due to the higher proportion of ambush hunters in recovered grassland and cropland. Secondly, the study also indicated that the proportion area of plantation forest negatively affected spider diversity at multi-scales. Meanwhile, recovered grassland with high landscape diversity would benefit spider diversity only on a small scale like a 100 m radius. The spider functional traits were insensitive to landscape patterns. Overall, the study implies that increasing recovered grassland rather than plantation forest could protect spider diversity in northern China. The findings presented in this paper added to our understanding of how landscapes and different semi-natural affect the diversity of spiders and their functional traits. Meanwhile, the research results represent a further step towards developing more suitable landscape patterns and choosing restoration semi-natural types for policymakers to enhance biodiversity in agricultural landscapes.

Agricultural intensification has resulted in major losses of biodiversity due to landscape homogenization and an increasing use of agrochemicals. It has often been assumed that associated changes in environmental conditions are impacting composition and diversity of two main ground-dwelling generalist predator taxa, carabid beetles and epigaeic spiders, in similar ways. Here, we test how variations in environmental conditions at local scales (plant diversity and total soil nitrogen, Ntot) and landscape-scale (mean patch size) affect species composition, richness and abundance of ground beetles and epigaeic spiders in semi-natural and cultivated habitats of an agricultural landscape. We specifically test the hypotheses that both taxa are more diverse in semi-natural than cultivated habitats, but that due to their weaker dispersal ability, ground beetles are more strongly linked to local factors than spiders. Our results indicate that in our study area, carabid diversity shows no significant difference between semi-natural habitats and cropland, while spider abundance is significantly enhanced in semi-natural habitats. Ntot significantly affected carabid species richness and abundance, but had a limited influence on spider abundances. The species composition of both carabids and spiders was influenced by plant diversity, while Ntot played a significant role in determining spider assemblages but not carabid composition. There was no significant effect of the mean patch size in the surroundings landscape on either spider or carabid species. Nonetheless, in landscapes with small patch sizes, spider abundance decreased with increasing Ntot, while in landscapes with large sized patches, this relationship was reversed. The differences in responses of these taxa to local and landscape-scale environmental factors suggests that scale- and taxon-specific targets need to be established to improve the efficiency of measures aimed at enhancing ecosystem services provisions by these key pest control agents.

Provisioning services have always been the main focus of agriculture, and which have led to a decline in biodiversity and have damaged a number of other services. Agriculture should contribute to current and future food security while producing multiple ecosystem services (ES). Restoration outcomes of multiple ES were affected by different socioeconomic drivers, thus a better understanding of how multiple ES respond to socioeconomic drivers can help to restore multiple ES. This paper used rural people's perceptions of ES to quantify and map ecosystem service obtainment and demand in the Mengyin County, China. An integrative index of multiple ecosystem services (IMES) was used to effectively aggregate the values of multiple ES. The threat categorization framework is designed to communicate the degree to which the adequate and sustainable provision of multiple ES is threatened, in order to prioritize conservation actions. The results revealed that 6 townships in the Mengyin County exhibited an excessive obtainment situation (demand is less than obtainment) of multiple ES; an insufficient obtainment situation (demand is greater than obtainment) of multiple ES was mainly situated in the northern part of Mengyin County. Overall, the current state of multiple ES across Mengyin County is classified as “Endangered” classification according to application of threat categorization framework. It is necessary to restructure and manage socioeconomic factors for multiple ES. At national level, the macro decision-making (controlling population density) and the mechanisms (attracting high-quality human resources into the rural) will play an important role in promoting multiple ES management, and it is necessary to provide 3 or more years of tailored educational resources for rural residents to advance multiple ES in agricultural landscape. Development of agricultural PES programs in China that enable farmers to profit from production ES is a sustainable strategy for increasing multiple ecosystem services.

Agricultural intensification has caused severe declines in ground-dwelling arthropods and associated ecosystem services. The conservation and re-establishment of semi-natural habitats in agricultural landscapes represent widely accepted measures to counter these declines. The effectiveness of these measures nonetheless varies between target taxa and their functional traits, while also being affected by local management. Here, we studied how species richness and abundance of different functional groups of carabid beetles and spiders in apple orchards were affected by landscape complexity (% semi-natural habitat) and local management intensity (mowing and soil total nitrogen (STN) content). Both abundance and species richness of non-carnivorous carabids and carabids overall were negatively affected by STN, while the abundance of carnivorous carabids and carabids overall was affected by interactive effects of mowing and landscape complexity, showing a positive response to mowing where semi-natural habitats are scarce, but negative responses in landscapes with a higher proportion of semi-natural habitats. The abundance of ground-hunting spiders and spiders overall was generally positively related to % semi-natural habitats, while the abundance of web-building spiders and the species richness of ground-hunting spiders showed a positive correlation with STN at landscapes with a low or medium abundance of semi-natural habitats, but a negative correlation where semi-natural habitats were more abundant. Non-carnivorous carabid diversity benefitted from low nitrogen application, while carnivorous carabid abundance benefitted from mowing intensity especially in simple and structurally homogenous agricultural landscapes. Both web-building and ground-hunting spiders positively responded to low nitrogen applications and intermediate landscape complexity. Overall, a low local management intensity promoted carabid beetles, while spiders were favored by increasing landscape complexity. We conclude that taxon- and functional group-specific, multi-scale conservation strategies are therefore required to conserve invertebrate predators in apple orchards.

Bees provide important pollination services for crops, but pollination limitation is a common problem in agricultural landscapes worldwide. To promote ecological intensification in fruit production, more knowledge is needed concerning the interacting effects of insect pollination services and soil fertility on crop quality and quantity. We investigated the effects of three pollination treatments (open, self and hand pollination) on apple quantity and quality parameters. We also analyzed the effects of bee abundance (wild bees and managed honeybees (Apis mellifera)) and soil nitrogen on fruit quantity and quality, and the responses of bee abundance and species richness to landscape metrics. Apple fruit set and yield of open pollinated flowers increased by 57 % and 25 t/ha (compared to bagged controls), respectively. Hand pollination further enhanced yields by 7 t/ha (compared to open pollination; i.e. to 39 t/ha), indicating pollination limitation in the orchards. Seed number was highest in open pollinated fruits, and increased with bee abundance if soil nitrogen was low, but decreased with bee abundance at high nitrogen levels, possibly due to higher flower density resulting in pollinator dilution effects. Higher seed numbers reduced the proportion of deformed apples and thus increased fruit quality. The percent of surrounding semi-natural habitats positively affected species richness of wild bees in apple orchards. We conclude that yield and quality of apples may benefit from ecological intensification comprising the augmentation of wild bees by semi-natural habitat and lowering of fertilizer inputs.

Agricultural land use is affected by government policies and leads to different consequences of regional sustainability. In this work, changes in cropping patterns including acreage, cropping locations and management-related environmental impacts were simulated under various policy scenarios for Quzhou County, China. This county is in China's major agricultural region, the North China Plain. Four dominant crop systems were categorized (winter wheat/summer maize, winter wheat/summer maize/spring maize, cotton, and vegetables) and analyzed, following two alternative policy scenarios that either prioritized government funding to subsidize crop production (“subsidy” scenario) or promoted advanced irrigation techniques (“technique” scenario). Input–output coefficients for all four crop systems were determined, mainly irrigation demand, yield, and price of produce, but other factors like a limited area of arable land and scarce regional water resources were also considered. For the simulation, a LINDO Inc. system was linked with the CLUE (Conversion of Land Use and its Effects) model. Temporal changes of crop systems were simulated with the LINDO system, whereas spatial dynamics of cropping patterns were simulated with the CLUE model, based on land suitability maps. The results show that crop patterns changed variably with time under the two scenarios, and water availability was the primary constraint on sustainability of land use. Under the subsidy scenario, winter wheat/summer maize/spring maize became dominant across the entire county, replacing other crop systems. In contrast, the vegetable system gradually occupied farmland surrounding the township under the technique scenario. The different policies produced opposite consequences for regional sustainability. Although a “subsidy” policy contributed to farmers’ income, it did not encourage water conservation for sustainable crop production, leading to land abandonment because of water shortage. In contrast, the “technique” policy partially cut direct financial benefits to farmers, but promoted water conservation and made a substantial contribution to agricultural sustainability.

Improper land use is one major cause of non-point source pollution. Integrated modeling would support the evaluation and optimization of land use for the non-point source pollution control. In this study, the CLUE-S (the Conversion of Land Use and its Effect at Small regional extent) and SWAT (Soil and Water Assessment Tool) models were coupled to simulate pollution loads under different land use scenarios in the upstream watershed of Miyun Reservoir in Beijing, China. The results indicated that changes in land use structure and pattern under different land use scenarios have significantly affected the non-point source pollution load. The increase of orchards and loss of forest cover has led to an increase in the potential pollution loads of nitrogen by 5.27% and phosphorus by 4.03%. However, in the agricultural non-point source pollution control scenario, pollution loads of nitrogen decreased by 13.94% and phosphorus by 9.86%, resulting from the establishment of riparian vegetation buffers and restoring forest on unutilized land and slope arable land. Coupling the hydrological model SWAT and the land use model CLUE-S succeeded in evaluating the land use pattern for agricultural non-point source pollution control. The coupling of two models provides a new approach for land use optimization towards non-point source pollution control. (C) 2011 Elsevier Ltd. All rights reserved.

Looking back at a history of more than 7000 years of agricultural production, Chinese agriculture had succeeded in supporting China's ever-increasing human population without changing the stability of the agro-landscape. The traditional biodiversity-friendly management of agricultural landscapes incorporated various elaborate techniques such as the use of organic manure, traditional integrative farming approaches like dyke–pond and rice–fishery systems, crop rotations and intercropping as well as the preservation of traditional agricultural landscapes including diverse natural and semi-natural elements. These systems were developed to maintain landscapes with healthy soil quality, a complex structure and diverse habitat composition, which favoured the sustenance of diverse species and a stable ecosystem functioning. While many biodiversity-friendly elements of traditional agriculture have been maintained, further developed or extended in modern agricultural practices in some regions, the biodiversity conservation in the agricultural landscapes is generally lacking of efficient policy support. Challenges and potential measures for biodiversity conservation in the context of Chinese agricultural landscapes are discussed.

Current approaches in terrestrial biodiversity conservation focus predominantly on plants and vertebrates. While these groups account for less than 4% of the estimated global species richness, it is commonly argued that especially the species richness in higher plants is a suitable indicator of overall biodiversity. We tested this assumption, investigating species richness and equitability patterns in three highly species-rich insect families and their links with the vegetation and other environmental factors. Vegetation surveys were combined with pitfall and light trapping to establish the α-diversity of ground beetles, geometrid moths and arctiid moths on 48 plots at varying altitudes between Beijing and the Inner Mongolian Plateau. Soil pH and nutrient status were also recorded. The α-diversity patterns in the three insect families were non-congruent, and links with phytodiversity were weak. The spatial α-diversity patterns in each of the three insect families were significantly correlated with the species density of individual plant families. These links varied between the three insect taxa and were mostly negative in moths. Furthermore, geometrid moth diversity decreased with increasing elevation and decreasing soil pH. Strongly diverging α-diversity patterns across different insect taxa illustrate that it is impossible to find a simple surrogate representing cross-taxon diversity for these highly diverse groups. Furthermore, phytodiversity and vegetation composition appear to play a limited role in governing insect diversity patterns. These results underline the significant risk that current plant-focused approaches in terrestrial biodiversity conservation are inadequate in addressing the conservation needs of the vast majority of species on earth.

The cellular automata (CA) model is an important tool in land use studies. Scale is a central concept in both land use research and CA models. To better understand the connection between different scales and processes of land use change, more studies on the behavior of a CA model at different scales are necessary and urgent. The objective of this study was to explore the impact of variation in scale on the behavior of a CA employed for land use change modeling. The scale variation was represented by the variation in the spatial extent of the images used, in the cell size and in the neighborhood configuration, including the size and shape. Two aspects of the behavior of the model were examined: the algorithms expressing the land use transitions, and the precision of the model’s output. The average enrichment factor, which generates the transition rules, was used to quantify the interpretation of the land use transitions. The kappa index was used to quantify the precision of the model’s output. The results showed that the variation of the spatial extent, cell size, and neighborhood size and shape influenced the model’s behavior in different ways. A combination of small cell size and small neighborhood size generated improper expressions of the land use transitions. Here, we believe that an increase in the neighborhood size might be the solution. However, the precision of the simulation decreased when the neighborhood size increased with ring shape. In addition, the precision first increased and then decreased once the neighborhood size reached a certain value for a scope-shaped neighborhood. Based on these results, we recommend the finest resolution and a neighborhood size of 9 × 9 cells arranged in a scope shape. This set of parameters reflects the most accurate land information. The model interprets well the land use transitions that are identical to those found in actual “real” land transitions and also provides high-precision outputs. For different model applications at different spatial scales, a preliminary discussion of the scale parameter setting is recommended.

The concept of participation is not intrinsic to the nature of Chinese planning systems; institutionally, they are centralized and top-down and lack local effective participation and communication between all actors. In recent years, participatory geographic information systems (PGIS) approaches have been used in natural resource planning and management. The paper discusses a concrete adoption of the methodology of PGIS into Participatory land use planning (PLUP) in the rural Shanxi province of China. A PGIS operational framework for PLUP is generalized from the project practice.

Diversity and species composition of carabid beetles were investigated at Quzhou county in the North China Plain. The study area was originally affected by high salinity and desalinized in three stages in 1973, 1978 and 1982. At sites desalinized in 1982, carabids were sampled at field margins as well as inside fields to investigate the role of field margins as refuge habitats. Furthermore, samples were taken from field margins desalinized in 1973 and 1978, respectively, to explore long-term developments of carabid assemblages following desalinization. At margins, soil salinity, N contents and the number of plant species as well as the height of dominant plants were recorded and their correlation with the species composition of carabids explored. Overall carabid diversity at Quzhou was low compared to areas not affected by high salinity. Field margins yielded significantly higher numbers of both species and individuals, whereas assemblages within the field had a low diversity and a homogeneous species composition. Carabid diversity slightly increased in relation to decreased soil salt contents and time elapsed since desalinization. These results may be explained by field margins serving as refuge to many carabid species and by an overall low species pool of carabids in Quzhou due to former high salinity, current high levels of fertilizer and pesticide applications, and by a comparatively low colonization rate of carabids to the area. As different carabid species varied strongly in their reaction to environmental parameters, the preservation of a diverse set of habitats will best protect the current diversity of these beetles in the agricultural landscape of Quzhou.