摘要
为了解城市复合土地利用系统中土壤磷素的积累和流失潜力特点,以浙江大学华家池校区为例,应用化学分析方法和GIS技术研究该校区复合土地利用系统中土壤磷素积累和流失潜力的时空变化特征.结果表明,近50年来,研究区内土壤全磷和有效磷呈明显的增加趋势,磷素积累受城市化和大量施用有机肥、化肥等的影响.土壤磷素空间异质性非常明显,深受土地利用方式的影响,土壤全P平均含量由高至低分别为畜牧场(3.22 g?kg-1)>果园(1.67 g?kg-1)>桑园(1.54 g?kg-1)>蔬菜地(1.52 g?kg-1)>教学区(1.37 g?kg-1)、绿化用地(1.37 g?kg-1)>水田(1.14 g?kg-1)>旱地(1.06 g?kg-1)>水旱轮作地(1.02 g?kg-1)、生活区(1.02 g?kg-1).研究区内土壤磷饱和度平均达22.29%,土壤水可提取态P明显高于一般农业区,有很高的P流失风险.土壤磷饱和度25%这一磷素流失风险临界指标也适合于对研究区土壤磷流失风险的评价,该指标大致与有效P 77 mg?kg-1和全P 1.20 g?kg-1相当.研究认为,城市复合土地利用系统中土壤磷素积累显著,磷素流失造成水体污染风险很大,应引起注意.
In order to understand the characteristics of accumulation and loss potential of soil phosphorus in urban complex land use system, this study, taken Huajiachi campus of Zhejiang University as a case, apply chemical analysis methods and GIS technology to explore the spatial heterogeneity in accumulation and loss potential of soil phosphorus in the campus. It was found that the accumulation of soil total and available P in the study area was noted last 50 years. The accumulation was significantly affected by both urbanization and heavy application of organic manure and chemical fertilizers. In this complex land use system, land use patterns still had significant impacts on soil P levels. There was an obvious spatial heterogeneity of soil P that decreased regularly from the northwest to the east. Soil total P decreased in the order of livestock farm （3.22 g·kg^-1）〉orchard （1.67 g·kg^-1 ）〉 mulberry garden（1.54 g·kg^-1）〉vegetable farm （1.52 g·kg^-1）〉educationarea （1.37 g·kg^-1）, forest land （1.37 g·kg^-1）〉paddy field （1.14 g·kg^-1 ） 〉 upland （ 1.06 g· kg^-1 ） 〉 paddy upland rotation field （ 1.02 g·kg^-1 ）, and resident area （1.02 g· kg^-1 ）. Both high degree of phosphorus saturation （DPS） with mean of 22.29% and high amount of water-soluble P of soil suggested that there was a great runoff risk of soil P in this area. The DPS 25%, which is considered to be a critical index of phosphorus loss risk, is also available to assess soil phosphorus loss risk in this area. The DPS 25% is equivalent to about 77 mg·kg^-1 available P and 1.20 g·kg^-1 total P. Attention should be paid to the accumulation of soil phosphorus in the urban complex land use system, since high soil phosphorus in the urban area could cause great impact to surface waters.
出处
《浙江大学学报（农业与生命科学版）》
CAS
CSCD
北大核心
2008年第4期453-460,共8页
Journal of Zhejiang University:Agriculture and Life Sciences
基金
浙江省自然科学基金资助项目(R306011)
关键词
城市复合土地利用系统
土壤磷积累
磷饱和度
空间异质性
GIS
urban complex land use system
P accumulation
degree of P saturation
spatial heterogeneity
geographic information system
作者简介
张慧敏（1985-），女，四川遂宁人，硕士研究生，主要从事资源管理与环境方面的研究．
通讯作者：章明奎，男，教授，博士生导师，从事土壤地理与污染元素的土壤地球化学行为方面的研究．Tel：0571-86946076；E-mail：mkzhang@zju．edu．cn．
