Abstract: By the methods of geostatistics, the spatial heterogeneity of soil organic matter, total nitrogen, total phosphorus, and total potassium in Ejina oasis was studied. All the test nutrient variables had significant spatial heterogeneity. The spatial variation of soil organic matter fitted exponential model, while those of soil total nitrogen, total phosphorus, and total potassium fitted spherical model. Soil organic matter, total nitrogen, and total potassium were greatly affected by soil structural factors, while soil total potassium was coaffected by structural and random factors. The spatial variation ranges of soil total nitrogen, total phosphorus, and total potassium were 7.68-7.86 km, and that of soil organic matter was comparatively small, being 5.4 km. The spatial distribution of soil nutrients was high in south and north oasis, and low in central oasis.

Key words: Microzooplankton, Phytoplankton, Carbon-to-chlorophyll a ratio, Grazing rate, Grazing pressure, Jiaozhou Bay