The vertical distribution of the dominant genera of plant nematodes at the depth of 0–150 cm of an aquic brown soil were studied for four land use patterns, i.e., paddy field, maize field, fallow field and woodland i...The vertical distribution of the dominant genera of plant nematodes at the depth of 0–150 cm of an aquic brown soil were studied for four land use patterns, i.e., paddy field, maize field, fallow field and woodland in the Shenyang Experimental Station of Ecology, Chi- nese Academy of Sciences in November of 2003. The results showed that the numbers of some dominant genera under different land uses decreased with the increase of soil depth. Helicotylenchus was most dominant genus under each land use type. Genera of Filenchus, Psilen- chus and Tylenchus in paddy field occurred at the depth of 0–20 cm; while Paratylenchus in fallow field and woodland, as well as Praty- lenchus in maize field presented in the deeper soil layers (0–80 cm). Significant correlations between the numbers of dominant genera of plant nematodes and soil chemical properties were found in this study. The number of Helicotylenchus under different land uses was posi- tively correlated with C/N ratio, total C, total N, total P, alkai-N, and Olsen-P. The numbers of Filenchus and Paratylenchus in paddy field, Pratylenchus in maize field and Paratylenchus in fallow field were negatively correlated with soil pH, and positively correlated with total C, total N and alkai-N. This study results showed that it is essential to sample at a certain depth according to the vertical distribution informa- tion of different genera of plant nematodes in adequately assessing the population size of plant nematodes.展开更多
An analysis of the seasonal and vertical distribution of soil nematode communities under three contrasting land uses,i.e.,cropland,abandoned cropland and woodland was conducted in an aquic brown soil.The results showe...An analysis of the seasonal and vertical distribution of soil nematode communities under three contrasting land uses,i.e.,cropland,abandoned cropland and woodland was conducted in an aquic brown soil.The results showed that different land-use types affected the spatiotemporal distribution of soil nematodes and their dominant genera,and different dominant genera showed different responses to land use.In the abandoned cropland and woodland,most dominant genera were present in the 0–20 cm layers and Chiloplacus was mainly distributed in the 5–30 cm layers,while in the cropland,Pratylenchus exhibited an even distribution from the 0–5 cm to the 40–50 cm depth.Soil environmental parameters under different land use could influence soil nematodes;soil porosity,total organic C,total N and the C/N ratio could positively influence the abundance of some dominant genera.Faunal profiles revealed that environmental stability and the homeostasis in the abandoned cropland and woodland lead to higher levels of community structure,and the soil food web tends to succeed to maturity.Nematode faunal analyses are a useful indicator for interpreting the stress and/or nutrient conditions under different land uses.展开更多
文摘The vertical distribution of the dominant genera of plant nematodes at the depth of 0–150 cm of an aquic brown soil were studied for four land use patterns, i.e., paddy field, maize field, fallow field and woodland in the Shenyang Experimental Station of Ecology, Chi- nese Academy of Sciences in November of 2003. The results showed that the numbers of some dominant genera under different land uses decreased with the increase of soil depth. Helicotylenchus was most dominant genus under each land use type. Genera of Filenchus, Psilen- chus and Tylenchus in paddy field occurred at the depth of 0–20 cm; while Paratylenchus in fallow field and woodland, as well as Praty- lenchus in maize field presented in the deeper soil layers (0–80 cm). Significant correlations between the numbers of dominant genera of plant nematodes and soil chemical properties were found in this study. The number of Helicotylenchus under different land uses was posi- tively correlated with C/N ratio, total C, total N, total P, alkai-N, and Olsen-P. The numbers of Filenchus and Paratylenchus in paddy field, Pratylenchus in maize field and Paratylenchus in fallow field were negatively correlated with soil pH, and positively correlated with total C, total N and alkai-N. This study results showed that it is essential to sample at a certain depth according to the vertical distribution informa- tion of different genera of plant nematodes in adequately assessing the population size of plant nematodes.
文摘An analysis of the seasonal and vertical distribution of soil nematode communities under three contrasting land uses,i.e.,cropland,abandoned cropland and woodland was conducted in an aquic brown soil.The results showed that different land-use types affected the spatiotemporal distribution of soil nematodes and their dominant genera,and different dominant genera showed different responses to land use.In the abandoned cropland and woodland,most dominant genera were present in the 0–20 cm layers and Chiloplacus was mainly distributed in the 5–30 cm layers,while in the cropland,Pratylenchus exhibited an even distribution from the 0–5 cm to the 40–50 cm depth.Soil environmental parameters under different land use could influence soil nematodes;soil porosity,total organic C,total N and the C/N ratio could positively influence the abundance of some dominant genera.Faunal profiles revealed that environmental stability and the homeostasis in the abandoned cropland and woodland lead to higher levels of community structure,and the soil food web tends to succeed to maturity.Nematode faunal analyses are a useful indicator for interpreting the stress and/or nutrient conditions under different land uses.