大石围天坑群生境土壤理化性质与球囊霉素的关系OA

To reveal the distribution characteristics of glomalin-related soil protein(GRSP)in the heterogeneous habitats(inside,fringe,and outside)of the Guangxi Dashiwei Tiankengs and its relationship with soil physicochemical properties,soils from these three microhabitats of the tiankeng were selected as the research objects.The contents of easily extractable glomalin-related soil protein(EE-GRSP)and total glomalin-related soil protein(T-GRSP)were determined.Combined with soil physicochemical indicators,methods such as Spearman correlation analysis and redundancy analysis were employed to systematically analyze the habitat differentiation characteristics of GRSP and explore its correlation with soil physicochemical factors.The results showed that among the three microhabitats,EE-GRSP was significantly higher outside the tiankeng(1.55 mg/g)than inside(1.35 mg/g),while no significant habitat difference was observed at the Fringe(1.52 mg/g).The T-GRSP content ranged from 3.17 to 3.51 mg/g,with no significant differences among habitats.The proportion of EE-GRSP to organic carbon(EE-GRSP/SOC)ranged from 3.51％to 4.72％,with the Fringe being significantly lower than outside and inside.The proportion of T-GRSP to organic carbon(T-GRSP/SOC)showed no significant differences among habitats.Based on the relationship between soil physicochemical factors and GRSP,it was indicated that organic carbon(SOC)inside the tiankeng,total nitrogen(TN)and total carbon(TC)at the Fringe,and total carbon(TC)outside the tiankeng were the core soil factors affecting GRSP content.Moreover,the accumulation of GRSP increases with the increase in soil carbon and nitrogen storage,while the proportion of GRSP to SOC decreased with the increase in soil carbon and nitrogen storage due to its accumulation rate lagging behind that of soil carbon and nitrogen.Additionally,the effects of soil moisture,pH,and TP on GRSP were habitat-specific.The study confirmed that the accumulation of GRSP in the tiankeng was influenced by habitat heterogeneity and soil carbon-nitrogen factors,and its carbon and nitrogen sequestration function played a key role in maintaining soil quality in the karst tiankeng ecosystem.