婺江流域农田不同利用方式下土壤碳氮含量特征

发布时间：2018-03-25 08:43

本文选题：土地利用方式　切入点：有机碳　出处：《浙江师范大学》2015年硕士论文

【摘要】：土地利用方式出现差异或变化,有机碳与全氮含量也不相同,对全球气候影响极大。本论文采用野外采集土样与室内实验分析相结合的办法,在2014年6月、7月在婺江流域烟溪村、二环北区域进行采样,主要土地利用方式包括：油菜地、苗木地、菜地、黄豆地、棉花地、西瓜地六种土地利用方式,对其进行了测定分析。通过研究探寻在土地利用类型不相同的情况下,土地利用对土壤有机碳、全氮、硝态氮、铵态氮、颗粒组分含量及其土壤理化性质的影响,为提高农田土壤生产功能、改善土壤中养分状况、生态环境的健康发展提供依据。主要结论如下：1、不同土地利用土壤有机碳、全氮含量的分布特征(1)0～60cm土层,土地利用类型不一致的情况下,土壤剖面加深,有机碳含量逐渐减少。烟溪村土壤有机碳在土壤剖面的分布大体表现为：0～20cm土层20～40cm土层40～60cm土层。0～20cm土层,土壤有机碳含量大小顺序：菜地苗木地油菜地黄豆地棉花地,菜地、苗木地、油菜地、黄豆地、棉花地土壤有机碳含量主要集中在0～20 cm土层,具有一定表聚性。0～60cm土层,菜地有机碳含量介于6.18～25.49g.kg-1,油菜地介于4.75～22.45g.kg-1黄豆地介于4.60～16.05 g.kg-1,苗木地介于6.81～21.85 g.kg-1,棉花地介于1.54～15.61g.kg-1。(2)土地利用类型不同,全氮含量表现出较大差异。0～10cm土层,菜地、苗木地全氮含量最高,分别为2.10g.kg-1,1.62g.kg-1。0～30cm土层,全氮排序：菜地苗木地黄豆地油菜地棉花地。油菜地、苗木地、菜地、黄豆地、棉花地五种土地利用类型全氮含量在0～30cm土层出现极大的分布特征与趋势的差别,30cm以下相差不大。土壤全氮含量在垂直剖面的分布与有机碳较为接近。2、不同土地利用硝态氮和铵态氮的分布特征各土地利用类型硝态氮在0～40cm土层累积含量在0～60cm土层总量比重分别为：油菜地86%、苗木地74%、菜地75%、黄豆地87%、棉花地88%,菜地土壤0～40cm土层累积含量达到61.11mg.kg-1。菜地土壤硝态氮含量在0-60cm土层显著高于其他土地利用类型,这主要是由于蔬菜类作物根系主要集中在土壤表层,有利于耕层土壤硝态氮聚合。土层剖面加深,油菜地、苗木地、菜地、黄豆地、棉花地土壤硝态氮含量均有不同程度的降低。总体看,土壤硝态氮在垂直剖面的分布表现为：0～20cm20～40cm40～60cm。铵态氮在整体的土壤剖面分布与硝态氮基本一致。3、不同土地利用方式土壤颗粒组成含量的差异不同土地利用,土壤颗粒颗粒粒级含量也不相同。按照美国的土壤机械组成划分标准,土壤颗粒组分分为三级：砂粒(0.05～2mm)、粉粒(0.002～0.05mm)、黏粒(0.002mm)。不同土地利用类型在同一土层,按0～10cm、10～20cm、20～30cm、30～40cm、40～50cm、50～60cm不同层次进行分析比较,每一种土地在相应土层砂粒、黏粒所占比重小,粉粒所占比重大,并且其含量超过50%。油菜地在土壤剖面20～30cm、40～50cm、50～60cm粉粒含量较低,黄豆地在土壤表层0～10cm粉粒所占百分比最高,30～40cm土层,各土地利用方式土壤颗粒组分各粒级所占体积百分比相差不大,棉花地在50～60cm土层与其他类型比较粉粒所占比例最大。同一土地利用类型下不同剖面间进行比较土壤颗粒组分含量变化也不相同。0～60cm土层,油菜地、苗木地、菜地、黄豆地、棉花地土壤粒级含量所占比重表现为：粉粒砂粒黏粒,黏粒所占比重大于50%。综合各种土地利用类型下土壤各粒级组分含量土壤质地属于粉壤或粉黏壤。
[Abstract]:Land use difference or variation of organic carbon and total nitrogen content is not the same, a great impact on the global climate. This paper adopts field collected soil samples and laboratory analysis method of combining, in June 2014, July in the smoke Creek Village of Wujiang River Basin, north of the ring area sampling, including the main land use type: rape, seedling, vegetable, soybean, cotton, watermelon, six kinds of land use, the analysis was conducted to explore. In the types of land use under the condition of the same through the study on soil organic carbon, total nitrogen, land use, nitrate nitrogen, ammonium nitrogen, particle content and its influence the physical and chemical properties of soil, in order to improve the production function of farmland soil, improve soil nutrient status, provide the basis for the healthy development of ecological environment. The main conclusions are as follows: 1. Soil organic carbon in different land use, the distribution characteristics of total nitrogen content (1) 0 ~ 60cm soil, land use types do not match, the depth of soil profiles, organic carbon content decreased gradually. The distribution of smoke village of soil organic carbon in the soil profile is roughly as follows: 0 ~ 20cm soil layer of 20 ~ 40cm, 40 ~ 60cm soil.0 ~ 20cm soil layer, soil organic carbon content in size order: Vegetable Seedling rape Rehmannia bean cotton, vegetable, seedling, rapeseed, soybean, soil organic carbon content in cotton soil mainly concentrated in 0~20 cm, with a certain accumulation of.0 ~ 60cm soil, vegetable organic carbon content ranging from 6.18 to 25.49g.kg-1, the rape was between 4.75 ~ 22.45g.kg-1 in soybean 4.60 ~ 16.05 g.kg-1, seedling ranged from 6.81 ~ 21.85 g.kg-1, cotton from 1.54 to 15.61g.kg-1. (2) in different land use types, total nitrogen content showed a greater difference between.0 ~ 10cm soil, vegetable, the total nitrogen content of seedling was highest, respectively. 2.10g.kg-1,1.62g.kg-1.0 ~ 30cm soil total nitrogen, ranking: vegetable bean seedlings Rehmannia rape. Rape cotton, seedling, vegetable, soybean, cotton, five kinds of land use types of total nitrogen content in 0 ~ 30cm soil layer distribution characteristics and trend of great difference, 30cm had no obvious difference. The content of soil total nitrogen and organic carbon vertical distribution is close to.2, the distribution characteristics of nitrate nitrogen and ammonium nitrogen in the different land use types of nitrate nitrogen in 0 ~ 40cm soil accumulation content in 0 ~ 60cm soil layer the proportion of the total respectively in different land use: rape 86%, 74% vegetable seedlings, 75%, soybean 87%, cotton 88% and soil layer of 0 ~ 40cm, the cumulative content reached 61.11mg.kg-1. soil nitrate nitrogen content in 0-60cm soil layer was significantly higher than that of other types of land use, which is mainly due to the vegetable crop root mainly concentrated in the surface soil Layer, is conducive to soil nitrate polymerization. Soil profile deepened, rape, seedling, vegetable, soybean, cotton to reduce soil nitrate content in varying degrees. In general, the performance of soil nitrate distribution in the vertical profile: 0 ~ 20cm20 ~ 40cm40 ~ 60cm. ammonium nitrogen in the soil profile and nitrate overall consistent.3, differences between different land use patterns of soil particle composition in different land use, soil particle size is not the same. According to the soil mechanical composition of the classification standard of soil particles were divided into three levels: (0.05 ~ 2mm), sand powder the particle (0.002 ~ 0.05mm), clay (0.002mm). Different land use types in the same layer, at 0 ~ 10cm, 10 ~ 20cm, 20 ~ 30cm, 30 ~ 40cm, 40 ~ 50cm, 50 ~ 60cm different levels of analysis and comparison, each kind of soil in the corresponding layers of sand, clay the proportion of Small particles, accounting for more than a major, and its content is more than 50%. of rape in the soil profile of 20 ~ 30cm, 40 ~ 50cm, 50 ~ 60cm powder with low content of soybean, in 0 ~ 10cm soil particle with the highest percentage, 30 ~ 40cm soil layer, the land use patterns of soil particle group each grade the percentage of the volume is small, the cotton in 50 ~ 60cm soil layer compared with other types of powder accounted for the largest proportion. The same land use comparison of soil particle content change is different for different types of.0 ~ 60cm soil profiles, rapeseed, seedling, vegetable, soybean cotton, soil particle content proportion is as follows: sand silt clay, clay proportion is larger than the 50%. of various types of land use under different soil particle fractions in soil texture belong to silt loam or silty clay loam soil.

【学位授予单位】：浙江师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S153.6

【参考文献】