摘要
探讨西藏土壤磷钾养分状况及其影响因素。结果表明西藏土壤全磷和全钾主要决定于母质。此外,土壤全磷与有机质呈正相关,故表层全磷高于底层,表现磷的生物表聚作用;而全钾与有机质呈负相关,故表层全钾低于底层,表现为有机质对钾的"稀释效应"。表层速效磷(Olsen-P)<10mg/kg的缺磷土壤面积约占78%,表明下层速效磷更低。土壤速效磷与全磷、有机质的关系复杂,而与pH的关系密切,一般在pH6.4～7.3的土壤中含量较高。西藏土壤表层速效钾100～150mg/kg和>150mg/kg的面积分别占17%和66%;并且速效钾主要决定于CEC,进而决定于有机质,而与粘粒关系不明显,与全钾无关。
This paper discussed the status of soil P and K nutrient and their influencing factors in Tibet. The results showed the soil total phosphorus (TP) and total potassium (TK) content were both mainly determined by the parent material. In addition, TP in surface layer was higher than subsurface layer due to significant positive correlation between TP and OM, which showed the biological surface accumulation of phosphors. While, TK in surface layer was lower than in subsurface layer because of significant negative correlation between TK and OM, which indicated the 'dilution effect' of OM to K. There was 78% of the soil area in Tibet that available P contents (AP) in the surface layer was lack, and the subsurface layer of that was lower. The relations of AP and TP, AP and OM were complicated, but the relation between AP and pH was close generally, especially higher in soil which pH was from 6.4 to 7.3. The area of soil available K contents (AN) which were 100~150 mg/kg and >150 mg/kg were 17% and 66% in Tibet, respectively. AK was influenced by CEC and OM, not relation with soil clay, and not influenced by TK.
出处
《水土保持学报》
CSCD
北大核心
2005年第1期75-78,88,共5页
Journal of Soil and Water Conservation
基金
国家"863"计划项目(990140046)资助
