摘要
采用蒋柏藩等的无机磷分级体系，研究了20年不同土地利用管理措施对耕层（0．20cm）无机磷组分的影响。试验包括4个处理，分别为小麦-玉米轮作体系不施肥（CK）以及氮磷配合（NP）、裸地休闲（Fallow）以及农田撂荒（Setaside）。结果表明：土壤无机磷总量变化范围为448．37mgkg-，752．5lmgkg-，长期配合施用氮磷肥显著提高土壤无机磷总量以及无机磷各组分的含量，其中以Ca2-P和Ca8-P增加幅度最大；长期不施肥土壤无机磷总量显著下降，主要体现在Ca2-P、Al-P以及0-P的含量的显著降低。尽管20年裸地休闲和撂荒无机磷总量均没有明显变化，但是无机磷各组分的含量发生了显著改变，其中Ca2～P、Al-P和Fe—P含量明显降低。壤土长期施用NP肥显著降低Ca10-P和AI—P占无机磷总量的比例，显著增加Ca2-P和ca，P的比例；长期不施肥显著增加Ca10-P比例，显著降低Ca2-P、Al-P和0-P的比僦。休闲和撂荒均显著降低Ca2-P和Al-P的比例。长期种植作物不施肥土壤无机磷组分中O—P与Al-P对作物的营养贡献率较大。而农田撂荒后植物生长的磷营养主要依赖于Ca2-P、Al-P和Fe—P。填土长期不同管理显著影响土壤无机磷总量、各形态磷的含量、各形态磷之间的相互转化以及各形态磷对植物磷营养的贡献。
By using the inorganic phosphorus fractionation method proposed by Jiang and Gu, we investigated the effects of contrasting soil management regimes on inorganic phosphorus （Pi） and its fractions in plough layer soils of a loess soil in a 20-year long term experiment were investigated in Shaanxi Province of China. Four treatments were included： receiving no nutrient addition under wheat-maize cropping system （CK）, application of nitrogen and phosphorus fertilizers （NP） with same cropping as CK, bare fallow （Fallow）, and cropland abanonment （Setaside）. The results showed that soil total Pi ranged from 448.37 mg kg-1- 752.51 mg kg-1 in plough layer soils （0 - 20 cm）. As compared with the initial values, long-term addition of N and P fractions, especially Ca2-P and CarP were drastically increased. significantly increased the contents of soil Pi and its While Pi content decreased markedly, mainly for the forms of Ca2-P, A1-P and O-P in CK plot. Although there were no clear changes in total concentrations of Pi under Fallow and Setaside over 20 years, the contents of Pi fractions, namely the Ca2-P, Al-P and Fe-P were decreased significantly. The proportions of Calo-P and All-P to total Pi dropped substantially, while those of Ca2-P and CarP to Pi were considerably enhanced in NP treated soil. Under CK, the ratio of Ca10-P to Pi was significantly increased, but those of Ca2-P, Al-P and O-P to Pi were markedly fallen. Both ratios of Ca2-P and Al-P to Pi were significantly decreased in the treatments of Fallow and Setaside. In addition, O-P and AI-P contributed the most to crops＇ P nutrition under CK. However, in the Setaside treatment, Ca2-P, Al-P and Fe-P were the predominant forms which were available to plants. Overall, different long-term management had noticeably influenced the soil Pi content, Pi fractions, transformation between Pi fractions and their nutritional contribution to plant growth.
出处
《土壤通报》
CAS
CSCD
北大核心
2013年第3期612-616,共5页
Chinese Journal of Soil Science
基金
公益性行业(农业)科研专项(201203030)
西北农林科技大学创新团队项目资助
