摘要
红壤一般偏酸且铁铝富集,磷与铁、铝形成Fe-P、Al-P,降低了红壤磷的有效性。施磷提高红壤供磷能力,但是未被作物利用的磷积累在土壤中,对水体环境构成威胁。研究红壤磷素状况对于提高作物产量和保护环境具有重要意义。已有很多关于红壤磷素状况方面的报道,但是很少将红壤磷素状况与水体磷进行关联分析。在典型红壤区江西省余江县布点采集了旱地和水田土样各54份,周边水样24份,分析了土壤有效磷(Olsen-P和Bray-P)含量、水溶性磷(CaCl2-P)含量和水样总磷含量。结果表明,以Olsen-P为指标,11%的旱地和39%的水田土壤缺磷,61%的旱地和39%的水田土壤磷适合作物生长,11%的旱地和11%的水田土壤处于高磷状态。以Bray-P为指标,11%的旱地和33%的水田土壤缺磷,6%的旱地和33%的水田土壤磷适合作物生长,77%的旱地和6%的水田土壤处于高磷状态。Olsen-P、Bray-P与CaCl2-P三者之间具有极显著相关关系,对Olsen-P与Ca Cl2-P、Bray-P与CaCl2-P分别进行回归分析,求得土壤磷流失突变点的Olsen-P和Bray-P含量分别为56.31和118.4 mg·kg^(-1)。依据这两个标准,水田土壤有效磷均未超过磷流失突变点,旱地土壤Olsen-P和Bray-P超过突变点的样品比例分别为50%和33%。水田周边排水沟渠水的总磷含量均低于《地表水环境质量标准》Ⅱ类水标准。总之,调查的红壤区水田土壤整体较为缺磷、磷流失风险低,旱地土壤有效磷含量和磷流失风险都较高。
Red soils are generally acid and contain more Fe and Al that can form Fe-P and Al-P,resulting in low P bioavailability.Applying P fertilizer can improve the capability of red soils to supply P for plants,but the P that is not used by plants accumulates in soils and has potential risks in polluting surface water.Researching soil P status has important implications for increasing crop yield and protecting ecological environment.Much more attention has been paid to the P status of red soils and surface water,but fewer studies pay attention to the direct link between red soil P status and surface water P pollution.We collected 54 soil samples in drylands,54 soil samples in paddy fields and 24 water samples around paddy fields in Yujiang County,Jiangxi Province.We determined the Olsen-P,Bray-P and CaCl2-P concentrations of soil samples,and the total P concentrations of water samples.The results showed that,according to Olsen-P,11%of drylands and 39%of paddy fields were P-deficient,61%of drylands and 39%of paddy fields were P-moderate,and 11%of drylands and 11%of paddy fields were P-excess.According to Bray-P,11%of drylands and 33%of paddy fields were P-deficient,6%of drylands and 33%of paddy fields were P-moderate,and 77%of drylands and 6%of paddy fields were P-excess.A extremely correlation was observed among Olsen-P、Bray-P and CaCl2-P.On the basis of the regressive analyses between Olsen-P and CaCl2-P,and between Bray-P and CaCl2-P,the change points of P loss were 56.31 and 118.4 mg·kg^(-1) for Olsen-P and Bray-P,respectively.According to the change points,the concentrations of Olsen-P and Bray-P in paddy fields never exceeded the P change point,but 50%and 33%of drylands exceeded the P change points of Olsen-P and Bray-P,respectively.The total P concentrations in the ditches around paddy fields never exceeded the total P standard for surface water in class II of the Environmental Quality Standard for Surface Water.Taken together,dryland soils have high available P concentrations and high P loss risk,whereas paddy soils have low available P concentrations and low P loss risk.
作者
肖作义
马飞
柳开楼
赵学强
郑春丽
张昊青
王嘉林
沈仁芳
XIAO Zuo-yi;MA Fei;LIU Kai-lou;ZHAO Xue-qiang;ZHENG Chun-li;ZHANG Hao-qing;WANG Jia-lin;SHEN Ren-fang(School of Environment and Energy,Inner Mongolia University of Science and Technology,Baotou Inner Mongolia 014010;State Key Laboratory of Soil and Sustainable Agriculture,Institute of Soil Science,Chinese Academy of Sciences,Nanjing Jiangsu 210008;Jiangxi Institute of Red Soil/National Engineering and Technology Research Center for Red Soil Improvement,Nanchang Jiangxi 330046;University of Chinese Academy of Sciences,Beijing 100049)
出处
《中国土壤与肥料》
CAS
CSCD
北大核心
2021年第1期282-288,共7页
Soil and Fertilizer Sciences in China
基金
国家自然科学基金项目(31672229)
江西省自然科学基金项目(20192BAB203022)。
关键词
旱地
水田
磷
流失风险
dryland
paddy field
phosphorus
loss risks
