Abstract: A pot experiment was conducted in greenhouse to explore the effect of vermicompost on soil fungal community structure of tomato continuous cropping. Four treatments were employed: vermicompost + chemical fertilizer (EM), chicken manure + chemical fertilizer (CM), chemical fertilizers (CF), and no fertilizer application as control (CK). The results showed that: (1) application of organic fertilizer significantly increased the pH value of continuous cropping soil; CM and EM treatments increased to 6.80 and 6.84, respectively, with an increment of 0.34 and 0.38 compared with CK, and a decrement of 0.37 and 0.41 compared with CF, respectively. Compared with the other three fertilizer treatments, EM treatment significantly increased the contents of soil organic matter, total carbon and total nitrogen. Organic matter content in EM increased by 2.41%, 7.86% and 9.60% compared to those in CM, CF and CK, total carbon content in EM increased by 5.09%, 7.67% and 7.13%, and total nitrogen increased by 7.14%, 21.43% and 18.57%, respectively. (2) The relative abundance of predominant fungi at phylum level was significantly decreased after vermicompost application. For example, the relative abundance of Basidiomycota in EM was 18% lower than that in CK, 14% lower than that in CF, and slightly lower than that in CM. (3) Redundancy analysis results showed that pH value had greatest influence on fungal community structure of different treatments, followed by total nitrogen, organic matter, carbon/nitrogen ratio, available nitrogen, available potassium, total carbon and conductivity, while soil moisture and available phosphorus had no significant effects on fungal community structure. Therefore, applying vermicompost in tomato continuous cropping soil can improve soil nutrient contents and reduce the relative abundance of dominant fungi, relieving the tomato continuous cropping obstacle.

Key words: soil heavy metal concentrations, partial least squares regression (PLSR), Yushu County., vegetation spectral reflectance, hyperspectral images