关键词: 紫色土, 有机碳, 微生物生物量碳, 磷, 微生物生物量磷, 施肥

Abstract: Based on the fishery resource data from the bottom trawl surveys conducted in the Zhejiang coastal area in November 2015 (autumn), February 2016 (winter), May 2016 (spring) and August 2016 (summer), we analyzed the ecological niche of dominant shrimp species using index of relative importance (IRI), niche breadth and niche overlap and canonical correspondence analysis (CCA). The results showed that there were 12 dominant shrimp species, belonging to 5 families and 9 genera. The spatial, temporal and spatiotemporal niche breadth of dominant shrimps ranged from 0.98-6.16, 0.16-1.34 and 0.45-7.64, respectively. Solenocera crassicornishad the strongest capacity to use resources, whereas Alpheus digitalis was the least. The niche overlap value between Alpheus japonicusand Alpheus digitaliswas the highest, indicating that these species were highly similar in resource utilization. Acetes chinensis (a pelagic and middle planktonic species) and Metapenaeus joyneri (a migratory shrimp in estuaries) had niche differentiation with other species in spatial and temporal dimensions. Organic matter, chlorophyll a, and suspended matter in water were the main factors driving the distribution of dominant species, which was associated with food habits. Temperature had slight effects on shrimp community due to the great dominance of eurythermal and euryhaline species. Salinity had substantial impacts on the eurythermal and hypohaline species, Acetes chinensis and Alpheus digitalis.

Key words: purple soil, organic carbon, microbial biomass C, phosphorus, microbial biomass P, fertilization.