Effect Of Soil Nematode Communities On The Home-field Advantage Of Forest Litter Decomposition

This study expounded the effect of soil nematode communities on the home-field advantage of the leaf litter decomposition of Pinus thunbergii Parl and Quercus liaotungensis Koidz,using litterbags with different mesh sizes in Dalian National Forest Park,China.We analyzed the soil nematode community composition,diversity and distribution,litter decomposition rate,and nutrient release.Furthermore,we studied a correlation between the number of nematodes,number of genera,ecological indices,and litter physico-chemical properties.The results showed that a total of 4570 nematodes belonging to 35 genera were collected.Among them,plant parasitic nematodes and bacterivores predominated.The plant-parasites nematodes and bacterivores nematodes at home were higher than that in the away,and there was a significant difference of the number of plant-parasites nematodes and bacterivores nematodes between home and away(P<0.05).The number of nematodes collected in 0.1-mm litter bags(4407)was significantly more than that of the nematodes collected in 0.02-mm litter bags(163).Litter decomposition was driven by soil nematodes and microorganisms in the treatment with 0.1-mm litter bags.However,soil nematodes were controlled by 0.02-mm litter bags;therefore,soil nematodes were regarded as the only microorganisms involved in litter decomposition.Litter mass loss rate and C and N release quantity in 0.1-mm litter bags were more than that in 0.02-mm litter bags.Litter mass loss rate and C and N release quantity in the home environment were more than that in the away environment.Some differences in the environment of home and away showed that soil nematodes promoted litter decomposition and significantly contributed to home-field.An increase was observed in the difference of litter loss rate and element residual rate between home and away.It showed that soil nematodes had an obvious effect on the home-field litter decomposition.In the process of decomposition,difference of dynamics of C and K elements remaining were all positive values,showing the positive effect.While difference of dynamics of N and P elements remaining between home and away were all negative values in the early stages of decomposition,showing the negative effect.In the middle and later periods,difference of dynamics of N and P elements remaining between home and away were all positive values,showing the positive effect.The spatial distributions of SR index,H' index and J index showed Qh treatment were higher than Qa treatment,and Ph treatment were higher than Pa treatment,showing that soil nematodes had a high degree of community richness.There are more nematodes and species,regulating and controlling community structure and edaphon activity,and further accelerated litter decomposition and nutrient release.Meanwhile,the home-field advantage also determined litter decomposition rate and nutrient release.These results will provide a reference for the home-field and away-field advantage of litter decomposition and for the soil organism-driven effect on the forest litter decomposition in a related study in the future.