Field studies were conducted to investigate effects of rice straw incorporation and nitrogen application models on process of nitrogen uptake by rice paddy ecosystem and fertilizer-N use efficiency in the double rice cropping system.

Therefore, there is a carbon circulation within the rice paddy ecosystem.

Soil samples were collected from long-term monitoring plots of paddy field ecosystem in Hunan Province to study the evolvement characteristics and coupling relationship of soil organic carbon and total nitrogen under different fertilization practices.

The gas regulation function of rice paddy ecosystems and its value;