作 者：
唐光木;徐万里;盛建东;梁智;周勃;朱敏
单 位：
新疆农业科学院土壤肥料与农业节水研究所;新疆农业大学草业与环境科学学院
关键词：
垦殖年限;有机碳;土壤颗粒粒径;绿洲农田;新疆
摘 要：
研究不同开垦年限新疆绿洲农田土壤有机碳及不同粒径土壤颗粒有机碳的变化规律,评价长期垦殖对新疆绿洲农田土壤有机碳的影响。以相应未开垦地为对照,选取南北疆兰州湾、31团和普惠农场三个典型绿洲不同开垦年限土壤为研究对象,应用物理分组方法研究不同粒径土壤颗粒中有机碳含量及分布。结果表明:(1)开垦有利于新疆绿洲农田土壤总有机碳的积累,开垦初期(0～5a)增加迅速,年均增加0·5gkg-1,10a后增加趋于平缓。(2)垦殖增加了不同粒径土壤颗粒有机碳的含量,砂粒有机碳在垦殖10a间达到最大值后趋于相对稳定的水平;粉砂粒和黏粒有机碳随垦殖年限延长增加。(3)开垦提高了POC/MOC值,表现为开垦初期(0～5a)增加迅速,10a左右达到最大值后开始下降。研究说明,新疆绿洲区域未开垦地开垦增加了土壤总有机碳和不同粒径土壤颗粒有机碳含量,随垦殖年限延长,粉砂粒和黏粒有机碳成为绿洲农田土壤主要碳库,土壤自身生产力存在下降可能,土壤质量存在潜在退化风险。
译 名：
THE VARIATION OF SOIL ORGANIC CARBON AND SOIL PARTICLE-SIZE IN XINJIANG OASIS FARMLAND OF DIFFERENT YEARS
作 者：
Tang Guangmu1,2 Xu Wanli2 Sheng Jiandong1 Liang Zhi2 Zhou Bo2 Zhu Min2(1 Faculty of Glassland and Environment Sciences,Xinjiang Agricultural University,Urumqi 830052,China)(2 Institute of Soil and Fertilizer and Agricultural Sparing Water,Xinjiang Academy of Agricultural Science,Urumqi 830091,China)
关键词：
Cultivation period; Organic carbon content; Organic matter quality; Oasis farmland; Xinjiang
摘 要：
The variation of organic carbon content and its distribution in different particle-size fractions in oasis farmland soils with different cultivation history in Xinjiang was studied,and the influence of long-term cultivation on soil organic carbon characteristics in the northwest arid area was discussed in this paper. Soil samples were collected from native land (without cultivation,used as a control) and three typical farming land with different cultivation times,including oasis soil in Lanzhouwan,NO31 Farm and Puhui Farm in southern and northern Xinjiang. A physical fractionation method was applied to study the content of organic carbon and its distribution in different particle-size fractions of the soil.The results were summarized as follows. (1) Cultivation practices enhanced to the accumulation of total organic carbon in soils,increased rapidly in the initial period (1～5 a)with an annual average increase about 0.5 g kg-1, but the increase was diminished after 10 years of cultivation. (2) Cultivation practices increased the content of organic carbon in different particle-size fractions. Organic carbon in the sand fraction reached its maximum in 10 years after cultivation and tended to be stable afterwards. Organic carbon in the silt and clay increased continuously with cultivation time. (3) Ratio of particulate organic carbon (POC) and mobile organic carbon (MOC) increased rapidly with cultivation in the initial period (1～5 a),reached its maximum in 10 years after cultivation,and started to decline afterwards. These results indicate that cultivation practices in the oasis farmland area of Xinjiang facilitates the accumulation of organic carbon in soils,particularly in the silt and clay size fractions and tends to improve the quality of organic matter as evidenced by the increased ratio of POC over MOC in the first 10 years after cultivation. However,extended cultivation for more than 10 years may cause decline of organic matter content in soil,thus affecting soil quality sustainability.Therefore,management practices need to take consideration of increasing organic matter inputs.
