Assessment of Changes in Agroecosystem Health in Guangzhou, China
Agroecosystem health refers to the extent to which a healthy agroecosystem can meet socioeconomic and biophysical needs of all residents over time. According to the attempts at assessing agroecosystem health, agroecosystem health depends on both functional and structural characteristics at regional level. However, both functional and structural characteristics have been altered from their natural state by industrialization and urbanization. Thus, this study reports a system-based assessment index to evaluate the health statue of agroecosystem in Guangzhou, South China. Agroecosystem health index (AHI) of Guangzhou decreased from 0.78 in 2000 to 0.71 in 2010. It indicated that this agroecosystem was at relatively healthy state. However, functions of both cultural service and economic sustainable development were not successful as they represented ‘worst’ and ‘sub-healthy’, respectively. With the decreased values between 0.7 and 0.9, the other indices also revealed the need for caution. Particularly, both habitatstructure index and provisioning service index exhibited well defined declines duringthis study period. This study suggests that AHI can be potentially employed to monitor the temporal change in agroecosystem health status, although AHI has some certain limitations and needs further improvement for the complexity of agroecosystems.