Salinity effects on soil organic carbon and its labile fractions, and nematode communities in irrigated farmlands in an arid region, northwestern China |
| |
| Authors: | YongZhong Su TingNa Liu XueFen Wang and Rong Yang |
| |
| Institution: | Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China;Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China;Jinlin Agricultural University, Changchun, Jilin 130118, China;Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, Gansu 730000, China |
| |
| Abstract: | The effects of salinity on soil organic carbon (SOC) and its labile fractions including microbial biomass carbon (MBC) and easily oxidation organic carbon (EOC), basal soil respiration, and soil nematode community in the Fluvents, an oasis in an arid region of northwestern China were investigated. Five sites were selected which had a salinity gradient with different groundwater table from 1.0 m to 4.0 m. Soils were sampled at the 0-20 cm plough layer from 25 irrigated fields of five sites and electrical conductivity was measured in the saturation paste extracts (ECe). Soils were categorized into five salinity levels:(1) non-saline, (2) very slightly saline, (3) slightly saline, (4) moderately saline, and (5) strongly saline according to the values of ECe. The results show that SOC and total nitrogen concentration, cation exchange capacity (CEC), and the concentrations of labile organic fractions (MBC, EOC), and basal soil respiration decreased significantly with increasing ECe. The relationships between ECe and MBC, EOC and basal soil respiration were best described by power functions. Slight and moderate salinity had no significant impact on soil nematode abundance, but excessive salt accumulation led to a marked decline in soil nematode community diversity and abundance. Soil salinity changed soil nematode trophic groups and bacterivores were the most abundant trophic groups in salt-affected soils. Further study is necessary to identify the response of soil microbial processes and nematode community dynamics to soil salinity. |
| |
| Keywords: | salinity soil organic carbon labile organic carbon basal soil respiration soil nematode |
| 本文献已被 CNKI 万方数据 等数据库收录！ |
| 点击此处可从《寒旱区科学》浏览原始摘要信息 |
| 点击此处可从《寒旱区科学》下载免费的PDF全文 |
|
