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City agencies across multiple continents have invested millions of funds in ambitious afforestation projects in urban and peri-urban areas to enhance the city green infrastructure. One example is the Beijing One Million Mu Plain Afforestation Project, which has established 146,000 ha of plantation forests, mainly on arable lands. This contradicts the national arable land conserving policies and has dramatically changed local habitat types and landscape context. However, the impact of these processes on biodiversity is not well understood. To investigate this impact at local and landscape scales, we explored a space-for-time approach. We selected 12 plantation forests and their nearby arable lands along a gradient of plantation forest cover in the surrounding landscapes. We surveyed ground spiders and carabids and analyzed their responses to local habitat type, landscape context, and their interaction. In the sampled landscapes, plantation forest cover increased (12.0%–35.9%), while arable land cover decreased (58.3%–31.8%). 96.3% of the new plantation forests were established on arable lands. Intensive afforestation on arable lands did not increase local ground arthropod diversity. In fact, ground arthropod abundance and species richness in plantation forests were significantly lower than in arable lands when the surrounding arable land cover was relatively high. With surrounding arable land cover decreasing, ground arthropod abundance and species richness in plantation forests increased but did not exceed those in nearby arable lands. Hence, the overall ground arthropod diversity at landscape scale was not improved. These findings suggest that, from a biodiversity conservation perspective, plantation forests did not surpass peri-urban agricultural lands as a better green infrastructure . However, ground arthropods benefit from rich local non-crop herb communities. Conserving peri-urban agricultural lands and implementing extensive management regimes for agricultural lands and existing plantation forests are more effective tools than ambitious afforestation of agricultural land in peri-urban areas of Beijing and other metropolises.

The agro-pastoral ecotone serves as an important ecological transition zone between grassland and cropland. It plays a crucial role in providing forage and maintaining the ecological security of Northern China. China has initiated many ecological restoration projects in the agro-pastoral ecotone. Separating the affecting factors of anthropogenic activities and natural factors change on grassland may help guide future ecological restoration projects. This study investigated the grassland change over the agro-pastoral ecotone in Inner Mongolia (APEI) using land use data, vegetation index, and monthly climate data, social and economic data from 2010 to 2020. Two indicators were introduced to evaluate the grassland change in quality and quantity. The average annual maximum NDVI of grassland within each sample was used as a proxy for grassland quality, and the proportion of grassland within each sample was used as a proxy for grassland quantity. The driving mechanisms of grassland quality were examined on different types of grassland. The results showed that (1) from 2010 to 2020, the quantity of grassland in APEI slightly decreased while the quality of the grassland significantly improved; (2) the change in grassland quality was jointly caused by natural factors and human activities, with 66.77% being attributed to natural factors and 33.23% to human activities. In some areas, the alteration in grassland quality was solely determined by either the impacts of natural factors or human-induced disturbances; and (3) temperature and precipitation played different roles in affecting grassland quality among different types of grassland. In some areas, anthropogenic activities, such as farmland and population, would affect grassland quality. The findings of this study would contribute to the understanding of the mechanism of ecological environmental changes in the agro-pastoral ecotone and guide the planning and implementation of future ecological restoration projects in agro-pastoral areas.

Abstract In the intensively farmed, homogenous agricultural landscape of the North China Plain, family graveyards form distinct cultural landscape features. In addition to their cultural value, these graveyards represent semi-natural habitat islands whose potential roles in biodiversity conservation and ecological functioning has remained poorly understood. In this study, we investigated plant species richness on 199 family graveyards of different ages and sizes. In accordance with biogeography theory, both overall and insect-pollinated plant species richness increased with area and age of graveyards. Even small graveyards show a strong potential for conserving local plant richness, and a mosaic of both large and small family graveyards could play an important role in the conservation of farmland biodiversity and related ecosystem functions. The launch of agri-environmental measures that conserve and create semi-natural habitats, in turn benefitting agricultural biodiversity and ecological functioning, has proven difficult in China due to the shortage of dispensable arable land. Given the great value of family graveyards as semi-natural habitats reflected in our study, we propose to focus preliminary efforts on conserving these landscape features as existing, widespread and culturally important semi-natural habitat islands. This would represent an effective, complementary policy to a subsequent re-establishment of other semi-natural habitats for the conservation of biodiversity and ecological functioning in agricultural landscapes.

Agricultural intensification has caused losses of global biodiversity and associated ecological services. Agroecological landscape assessments are therefore often based on the area of remaining semi-natural habitats due to their ability to promote biodiversity. Due to their structural diversity and often less intensive management in comparison to annual crops, perennial cropland could fulfil similar roles. However, comparisons of the ability of perennial cropland versus semi-natural habitat to maintain agricultural diversity are scarce. Here, we conduct such an assessment, in comparing functional group-specific patterns in ground beetles (Coleoptera: Carabidae) as indicators of anthropogenic land-use impacts on biodiversity and biological pest control. Carabid assemblages were compared between annual cropland (56 plots), perennial cropland (24 plots) and semi-natural habitats (74 plots) of varying plant diversity across nine study regions situated in Eastern China. Our results indicated that perennial crops sustained a greater carabid species richness than semi-natural habitats, whereas assemblages of semi-natural habitats contained greater proportions of large and predatory carabids. Plant species richness positively affected the overall diversity of carabids, with the strongest effects again observed in perennial cropland. Abundance-based and species-based proportions of large carabids were positively linked to plant diversity in perennial cropland and semi-natural habitats, but negatively in annual cropland. A similar response was observed for predatory carabid abundance. Perennial crops might therefore fulfil complementary roles to semi-natural habitats in agricultural biodiversity conservation. Given common trade-offs between biodiversity conservation and agricultural production, promoting perennial cropland in particular in combination with management that increases plant diversity, could enable increases in the sustainability of agricultural production systems particularly in areas with high food demand, but limited availability of arable land. Notwithstanding, semi-natural habitats remain crucial particularly with view of enhancing biological pest control services.

Understanding the characteristics of rural landscape change during the urbanization process is crucial to developing more elaborate rural landscape management plans for sustainable development. However, there is little information revealing how rural landscapes change at a local scale and limited evidence addressing how to improve the practicability of these management approaches. This paper aims to investigate local rural landscape compositions and patterns and to identify the spatial variability of local rural landscape change under rapid urbanization in eastern China to provide detail approaches to practicable and efficient local landscape management. The land use composition and landscape pattern from 2009 to 2012 were analyzed in three rural areas, namely, Daxing (DX) in Beijing, Quzhou (QZ) in Hebei Province and Changshu (CS) in Jiangsu Province. The results showed that the three rural areas varied in landscape pattern and land use composition change, even in the short term. Local farmland decreased slightly, demonstrating the effectiveness of the national farmland protection policy. Compared to the other two rural areas, CS was more diverse, fragmented and complex, and it had the greatest change rate between 2009 and 2012. In this rural area, semi-natural land dramatically increased, from 9.15% to 39.85%, and settlement construction unexpectedly decreased. QZ was characterized by a highly homogenous landscape dominated by farmland, which accounted for more than 80% of the total area, and it showed a slow decrease in farmland with weak increases in semi-natural land and construction. DX was characterized by a simple and homogenous landscape and had a median change rate of 9.32%, presenting a common land use change trend of a fast expansion in construction but decreases in farmland and semi-natural land. During decreases in highly valuable natural land, semi-natural land was important for nature conservation in rural areas at a local scale, but that process needs further improvement, especially in DX and QZ. Generally, local rural landscapes became more disaggregated and diverse during landscape change. Land use switches among farmland, orchards, nurseries, and other production lands were the major driving force for local change. Considering differential characteristics of landscape change among rural areas, we suggest that efficient landscape management requires the development of strategies that account for the spatial variability of urbanization effects. Subsidies for the management of semi-natural land with high natural value are meaningful for local natural conservation.