Effects of agricultural landscape heterogeneity on biodiversity and ecosystem services

It is undoubted that biodiversity and its’ ecosystem services have significant importance for agricultural landscape. The semi-natural habitats are the indispensable covers in agro-landscape, which maintain higher biodiversity because they provide refuge, foods, breeding place. To meet the demands of a growing human population, agricultural systems have been enlarged by altering non-crop habitats area to crop land and produced more crops per unit area, the disturbance to ecosystem intensified inducing decreasing of biodiversity. Keeping high biodiversity in agricultural landscape is significant for sustainable development of agriculture. In this paper, composition and characteristics of agricultural landscape heterogeneity were reviewed and its effects on biodiversity and ecological service discussed. Landscape heterogeneity included compositional heterogeneity, configurational heterogeneity, as well as temporal heterogeneity and functional heterogeneity. Most evidences showed that higher heterogeneity of agro-landscape affected positively on biodiversity. The temporal dynamics (historical, short-term and seasonal change of landscape) of landscape context may help improving understanding about the interaction between landscape structure and biodiversity in agro-landscape. Scale effect of landscape heterogeneity on biodiversity existed and is a core content of landscape ecology. Multi-scale effects of spatial and temporal landscape heterogeneity on non-agricultural biodiversity were significant. The biodiversity of plants, ground arthropod, and soil fauna were related to landscape heterogeneity in different radius buffer area. The responses of different non-agricultural biological groups were different because the landscape context and biological characteristics. The mechanisms of landscape heterogeneity maintaining biodiversity was also summarized. The combination of plant dispersal modes (e.g. wind, animals, vegetative) or / animals migration modes (e.g. crawling, jumping, flying) and landscape structure (e.g. connectivity of semi-natural habitat, presence of dense non-crop habitats) determined how far plant and animal species could move through the landscape to reach suitable patches. Influences of landscape heterogeneity on bio-control, pollination, and material cycle that provided by natural enemy, flower visitors and soil fauna were overviewed too. More and more studies had shown landscape heterogeneity and agricultural managements were important driving factors of plant, animal, and microorganisms, and furthermore impacted ecosystem services, such as nutrient recycle, water adjustment, pest biocontrol, etc. Based on the results of a series study of effects of agricultural landscape heterogeneity on non-agricultural biodiversity in the middle and lower area of the Yellow River, the development and perspective of landscape heterogeneity and biodiversity were summarized. The further studies should focus on relationships between agro-landscape context and biodiversity and its mechanisms based on spato-temporal heterogeneity of landscape.