干旱区生态环境知识资源中心(Arid): 敦煌地区浅层包气带硝态氮的空间分布与富集特征

Arid

	敦煌地区浅层包气带硝态氮的空间分布与富集特征
其他题名	Characteristics of spatial distribution and accumulation of nitrate in the unsaturated soil profiles in Dunhuang
	赵梦竹; 马金珠; 孙朋; 赵玮; 张琨
来源期刊	环境化学
ISSN	0254-6108
出版年	2015
卷号	34 期号:10 页码:1823-1831
中文摘要	选取我国西北干旱区敦煌地区6种不同类型的典型土壤为研究对象,通过测定各土壤剖面Cl~-和NO_3~- 浓度,探究Cl~-和NO_3~-的空间分布特征以及NO_3~-的富集程度.结果表明,NO_3~- 与Cl~-的分布特征基本一致,并与水分含量具有良好的相关性,随包气带埋深的增加呈现波动递减的变化趋势.强烈的蒸散发作用和微生物的硝化作用使土壤表层的NO_3~-含量较高,植物根系对NO_3~-和水分的吸收降低了NO_3~- 浓度,并导致NO_3~- 与Cl~-的分布特征存在不同程度的差异性.不同类型土壤中的NO_3~-含量不同,盐碱地>林地>农田>草地>戈壁>沙漠.沙土可促进NO_3~-的淋溶,无植被生长的戈壁沙漠中较高的NO_3~-/Cl~-伴随较低的Cl~-含量说明硝态氮的富集主要发生在干旱阶段,蓝藻菌的固氮作用活跃,而农田土壤中硝态氮的富集受人为源影响显著.
英文摘要	By measuring the concentrations of Cl~- and NO_3~- in six typical soils collected from Dunhuang in northwest China, this study explored the spatial distribution characteristics of Cl~- and NO_3~- and accumulation of NO_3~-. The results indicated that the distribution characteristic of NO_3~- was similar to that of Cl~-, and both of them correlated well with the soil moisture. With the increase in the depth of the unsaturated zone, the concentration of NO_3~- displayed a decreasing trend of volatility. The intense evaporation and microbial nitrification resulted in relatively high NO_3~- content in the soil surface, while water and nutrition uptake by plant roots reduced the concentration of NO_3~- in the root zone. This process caused some differences in the vertical distributions between NO_3~- and Cl~-. The concentration of NO_3~- showed significant difference among different soils, with an order of saline>forest>farmland>grassland>gobi>desert. Because NO_3~- can easily leach out in sand soil, the lower level of Cl~- and high level of NO_3~-/Cl~- in gobi and desert indicated that nitrate enrichment mainly occurs in the arid phase and nitrogen fixation of cyanobacteria is active. However, nitrate enrichment in farmland soil was significantly affected by anthropogenic activities.
中文关键词	敦煌地区 ; 包气带 ; 硝态氮 ; 分布特征
英文关键词	Dunhuang basin unsaturated zone nitrate distribution characteristics
语种	中文
国家	中国
收录类别	CSCD
WOS类目	ENVIRONMENTAL SCIENCES
WOS研究方向	Environmental Sciences & Ecology
CSCD记录号	CSCD:5539768
来源机构	兰州大学
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/232903
作者单位	兰州大学资源环境学院, 西部环境教育部重点实验室, 兰州, 甘肃 730000, 中国
推荐引用方式 GB/T 7714	赵梦竹,马金珠,孙朋,等. 敦煌地区浅层包气带硝态氮的空间分布与富集特征[J]. 兰州大学,2015,34(10):1823-1831.
APA	赵梦竹,马金珠,孙朋,赵玮,&张琨.(2015).敦煌地区浅层包气带硝态氮的空间分布与富集特征.环境化学,34(10),1823-1831.
MLA	赵梦竹,et al."敦煌地区浅层包气带硝态氮的空间分布与富集特征".环境化学 34.10(2015):1823-1831.