[Theoretical basis of ecology for the influence of global change on resources, environment, and ecosystems.].

With the deepening of global change research, the applied problems such as global change risk and response for social sustainable development, temporal and spatial allocation of resources and environmental elements and impact assessment of ecosystem are becoming a new trend in the research field of global change. Based on the ecological framework, we focused on clarifying the connotations of resources and the environment and their components. Resources refer to all substances consumed by organisms in the process of producing organic matter from inorganic matter and transferring energy and matter among organisms.

Variations in seasonal and inter-annual carbon fluxes in a semi-arid sandy maize cropland ecosystem in China's Horqin Sandy Land.

Sandy cropland ecosystems are major terrestrial ecosystems in semi-arid regions of northern China's Horqin Sandy Land, where they play an important role in the regional carbon balance. Continuous observation of the CO flux was conducted from 2014 to 2018 using the eddy covariance technique in a sandy maize cropland ecosystem in the Horqin Sandy Land. We analyzed carbon fluxes (the net ecosystem exchange (NEE) of CO, ecosystem respiration (R), and the gross primary productivity (GPP) and their responses to environmental factors at different temporal scales using Random Forest models and correlation analysis.

Soil microbial community responses to short-term nitrogen addition in China's Horqin Sandy Land.

Anthropogenic nitrogen (N) addition has increased soil nutrient availability, thereby affecting ecosystem processes and functions in N-limited ecosystems. Long-term N addition decreases plant biodiversity, but the effects of short-term N addition on soil microbial community is poorly understood. The present study examined the impacts of short-term N addition (NH4NO3) on these factors in a sandy grassland and semi-fixed sandy land in the Horqin Sandy Land.

Temporal and spatial variation of extreme temperatures in an agro-pastoral ecotone of northern China from 1960 to 2016.

The agro-pastoral ecotone of northern China is one of the areas most sensitive to global temperature change. To analyze the temporal and spatial trends of extreme temperature events in this area, we calculated the values of 16 extreme-temperature indices from 1960 to 2016 based on data from 45 national meteorological stations. We found that the coldest-temperature indices decreased significantly and the warmest-temperature indices increased significantly.

Spatial pattern of soil organic carbon and total nitrogen, and analysis of related factors in an agro-pastoral zone in Northern China.

The spatial pattern of soil organic carbon (SOC) and total nitrogen (TN) densities plays a profound important role in estimating carbon and nitrogen budgets. Naiman Banner located in northern China was chosen as research site, a total of 332 soil samples were taken in a depth of 100 cm from the low hilly land in the southern part, sandy land in the middle part and an alluvial plain in the northern part of the county. The results showed that SOC and TN density initially decreased and then increased from the north to the south, The highest densities, were generally in the south, with the lowest generally in the middle part.