Long-term ecological research provides theoretical and technical support for ecological restoration and high-quality development in agro-pastoral ecotone

Since its establishment in 2001, the Duolun Restoration Ecology Station, Institute of Botany, Chinese Academy of Sciences (Duolun Station) has been dedicated to addressing severe grassland degradation and slow economic development in the agro-pastoral ecotone, north of Beijing. A series of systematic studies were conducted on the degraded grassland ecosystem in the agro-pastoral ecotone of Duolun County, Inner Mongolia. The major research findings are summarized as follows. (1) Elucidated that species-specific trait of plant roots, along with the changes in soil properties, are the primary drivers determining how plant and microbial community structure and function respond to anthropogenic disturbances and global climate change. (2) Unraveled the mechanisms by which warming and simulated frost events affect the carbon cycle of the agro-pastoral ecotone system. The results showed that the effects of warming are mainly caused by warming-induced changes in soil moisture, and that spring and autumn frost events tend to offset each other. (3) Revealed the mechanisms underlying the response of grassland ecosystem productivity and its stability to long-term water and nitrogen addition. Prolonged water input increased nitrogen losses, which intensified nitrogen limitation and shifted the resource-limitation pattern from co-limitation by water and nitrogen to nitrogen limitation alone. In addition, the stability of productivity responded in opposite directions to increased water and nitrogen inputs. (4) Developed product series and technologies for restoring degraded grasslands, established a comprehensive restoration technology model of grazing exclusion, root cutting, and snow-melting /rainy-season fertilization, and developed a series of high-yield pasture establishment technologies. These technologies have been widely implemented in the agro-pastoral ecotone, and achieved significant ecological and economic outcomes. (5) Proposed the scientific initiatives to build the agro-pastoral ecotone as the third granary, and provided a novel model of sustainable agro-pastoral development with Chinese characteristics to safeguard national food security through the strategies of “Storing grains in grasslands and livestock systems”.