景电灌区几种土地利用方式土壤有机碳和养分特征研究  

Soil organic carbon and nutrient content under different land use patterns in Jingdian Irrigation Zone

作　　者：李银科[1] 刘世增[1] 李发明[1] 满多清[1] 朱淑娟[1] 刘淑娟[1] 

机构地区：[1]甘肃省荒漠化防治重点实验室甘肃省治沙研究所,兰州730070

出　　处：《中国生态农业学报》2010年第2期267-271,共5页Chinese Journal of Eco-Agriculture

基　　金：PRC-GEF干旱生态系统土地退化防治伙伴关系项目"农村社区退化土地综合治理与生态系统可持续发展研究";甘肃沙漠综合治理技术研究创新团队项目(0707TTch020)资助

摘　　要：对景电灌区土壤次生盐渍化的1年生枸杞地和多年生枸杞地、未盐渍化的小麦地和苜蓿地4种土地利用方式土壤有机碳和养分状况进行对比研究, 结果表明： 在0～60 cm土层, 小麦地土壤有机碳含量及其密度、全氮和速效磷含量均最高, 苜蓿地均最低; 土壤全氮与有机碳含量呈极显著正相关（r=0.791, P〈0.01）; 4种利用方式C/N比值均较低, 多年生枸杞地C/N比值最高, 1年生枸杞地最低; 4种利用方式速效钾含量无显著差异; 苜蓿地容重显著高于其他3种利用方式, 这与其低的有机碳含量密切相关（r=0.420, P〈0.01）。与小麦地相比, 1年生枸杞地土壤有机碳含量及其密度显著降低, 全氮和速效磷含量有所降低; 与1年生枸杞地相比, 多年生枸杞地土壤有机碳含量及其密度有所增加, 全氮含量显著降低, 速效磷含量显著增加。这意味着该区耕地土壤发生次生盐渍化以后, 土壤性状恶化; 种植枸杞使次生盐渍化土壤性状有所改善。Soil organic carbon and nutrient contents were analyzed under four different land use patterns of annual medlar field （AMF） and perennial medlar field （PMD） in secondary saliferous soil, wheat field （WF） in un-saliferous soil and alfalfa field （AF） in wasteland in Jingdian Irrigation Zone. The analysis shows that organic carbon content and density, total nitrogen and Olsen phosphorus for WF are the highest, while those for AF are the lowest in the 0～60 cm soil layer. Soil total nitrogen has a significant positive correlation with organic carbon （r = 0.791, P 〈 0.01）. There is a generally low C/N ratio for all the soil samples, that for PMD is highest and that for AMF is lowest. There is no significant difference in available potassium among the land use patterns. Soil bulk density is signifi-cantly higher for AF, due mainly to the relatively low soil organic carbon content （r = 0.420, P 〈 0.01）. Soil organic carbon content and density are significantly lower while total nitrogen and Olsen phosphorus are higher under AMF relative to WF. Organic carbon content and density are also higher, total nitrogen content significantly lower and Olsen phosphorus content significantly higher un-der PMD in relation to AMF. An important finding of the study is that farmland soils deteriorate following secondary salinization whereas planting medlars improves soil physical and chemical properties in the study area.

关 键 词：景电灌区 土地利用方式 土壤有机碳 土壤养分 

分 类 号：S158.5[农业科学—土壤学]