摘要
柴达木盆地弃耕地土壤pH值一般都在 8左右 ,属于碱性土壤。土壤含盐量较高 ,其全盐量随着土层深度的增大而减少。 0～ 10cm土层中的含盐量最大 ,一般在 1～ 45gkg- 1之间。弃耕地土壤阳离子主要以K+ 、Na+ 、Mg2 + 、Ca2 + 为主 ,各阴离子在三层土体中的含量为Cl- >SO2 -4>HCO-3 >CO2 -3 。经相关分析表明 ,弃耕地土壤全盐量与Cl- 呈极显著的正相关 (p <0 0 1) ,其次为Mg2 + 和Ca2 + (p <0 0 5) ,而与HCO-3 呈负相关 ;Cl- 与Mg2 + 和Ca2 + 呈极显著的正相关 (p <0 0 1) ,与CO2 -3 和SO2 -4呈弱的正相关 ,而与HCO-3 呈负相关 ;从而进一步说明 ,柴达木盆地弃耕地土壤为氯化物盐化土。柴达木盆地弃耕地土壤中有机质含量较少 ,0～ 3 0cm土层中有机质平均含量为 11 46gkg- 1;全氮、全磷的含量极低 ,全钾的含量较为丰富。示范试验结果分析认为 。
Deserted farmlands in the Qaidam Basin are mostly of alkali soil with pH value around 8, high in salt content. Salts concentrate mostly in the 0～10 cm surface layer, ranging within 1～45 g kg -1 , and decrease in content with depth of the profile. Cations in the soil are dominated with K +, Na +, Mg 2+ and Ca 2+ , w hereas anions are in a decreasing order of Cl ->SO 2- 4 >HCO - 3 >C O 2- 3 in terms of content in the 0～10 cm,10～20 cm and 20～30 cm soil layers. The correlation be t ween total salt and Cl - content is positive and extremely significant (p< 0 01), and that between total salt and Mg 2+ , Ca 2+ content significantly pos itive, too (p<0 05), but that between total salt and HCO - 3 content neg ative, whereas, the co rrelation between Cl - and Mg 2+ , Ca 2+ content is positive and extre mely significa nt (p<0 01), and that between CO 2- 3 and SO 2- 4 content also significantly positiv e, but that between Cl - and HCO - 3 content negative. All these findings fu rther s uggest that the soils are heavy chloride saline soils. Organic matter contents o f the soils are low averaging 11 46 g kg -1 in the 0～30 cm soil layer. T he conte nt of total N and P of the soils are also very low, but the soils are rich in K . The results obtained from experimental area indicate that degradation and salini zation of the soils is closely related to the local natural conditions and irrat ional human activities in the region.
出处
《土壤学报》
CAS
CSCD
北大核心
2004年第1期44-49,共6页
Acta Pedologica Sinica
基金
国家"九五"科技攻关项目 ( 97- 92 4 - 0 2 - 0 3)
中国科学院资源与生态环境研究重点项目 ( 2 1 0 1 2 6 )
中国科学院海北高寒草甸生态系统定位站基金项目资助
