干旱区生态环境知识资源中心(Arid): 晋西北不同年限小叶锦鸡儿灌丛土壤氮矿化和硝化作用

Arid

	晋西北不同年限小叶锦鸡儿灌丛土壤氮矿化和硝化作用
其他题名	Soil nitrogen mineralization and nitrification under Caragana microphylla shrubs of different ages in the northwestern Shanxi Loess Plateau
	白日军 1; 杨治平 2; 张强2 ; 张训忠 3
来源期刊	生态学报
ISSN	1000-0933
出版年	2016
卷号	36 期号:24 页码:8008-8014
中文摘要	利用PVC管顶盖埋管法研究了晋西北黄土高原区小叶锦鸡儿人工灌丛不同定植年限(5,10,20,30,40a)土壤氮矿化与硝化速率的动态和净矿化与硝化总量。结果表明,⑴小叶锦鸡儿灌丛土壤无机氮主要以NO_3~- -N形式存在,不同生长年限相同月份的土壤硝态氮(NO_3~- -N)含量分别是铵态氮(NH_4~+ -N)含量的1.515.4倍; ⑵土壤氮素硝化速率和矿化速率随生长年限延长而加快, 30年生时达到高峰,数值达40.2, 44.1 mg m~(-2) d~(-1)。从季节性变化看,78月份是硝化速率和矿化速率快速增长期, 30年生小叶锦鸡儿灌丛土壤硝化速率和矿化速率分别达到86.9,93.1 mg m~(-2) d~(-1),显著高于其它生长年限(P< 0.05); (3)土壤氮素硝化与矿化总量同样随小叶锦鸡儿生长年限延长而增加,30年生时达到最高,与5年生相比,分别增加了3.7和3.1倍。 (4) 510月份小叶锦鸡儿生长期内,各年限土壤全氮量的2.3%被矿化成无机氮,其中87%最终被转化成NO_3~- -N形式存在于土体中。
英文摘要	Nitrogen (N) is a main limiting factor for plant growth and development in many regions. Soil organic N, accounting for up to 95% of the soil N pool,cannot be used by plants directly,but can be absorbed and utilized by plants after being mineralized into nitrate N (NO_3~- -N) and ammonium N (NH_4~+ -N). Therefore,soil net N nitrification (Nnit) and net N mineralization (N_(min)) rates have been considered two important indicators for evaluating the stability and function of an ecosystem. Caragana microphylla,a leguminous and sand-binding shrub,is a dominant species widely distributed in the Loess Plateau of northwestern Shanxi. Previous studies on soil N dynamics have mainly focused on forest,grassland,and farmland ecosystems to study the effect of environmental factors such as temperature and humidity on soil N mineralization and nitrification. However,few researchers have focused on soil N dynamic changes under shrub lands in arid and semiarid regions. The objective of this study was to explore the content of NO_3~- -N and NH_4~+ -N and the rate of soil net N nitrification and net N mineralization under Caragana microphylla shrubs as a function of plant age. We used a closed-top PVC tube in situ incubation method to detect the soil net N mineralization and net N nitrification in Caragana microphylla shrubs of different ages (5,10,20,30,and 40 a) in the northwest Shanxi Loess Plateau. The results indicated that NO_3~- -N accounted for a larger proportion of mineral N in Caragana microphylla shrub soil. The NO_3~- -N concentration was 1.515.4 times higher than NH_4~+ -N in the same month of different years. Soil net N nitrification and net N mineralization rates increased as the Caragana microphylla shrubs’ ages increased,with the greatest average rates from May to October (40.2 and 44.1 mg m~(-2) d~(-1),respectively) being observed under 30-year-old shrubs. The net N nitrification and mineralization rate increased faster in July and August relative other months during the growing season. The net N nitrification and mineralization rates were 86.9 and 93.1 mg m~(-2) d~(-1),respectively,at 30-year-old shrubs,which had the highest rates of all age classes (P< 0.05). The total net N nitrification and mineralization also increased with increased age of Caragana microphylla. The total net N nitrification and mineralization from May to October increased by 3.7-and 3.1-fold at 30-yearold shrubs,respectively,relative to 5-year-old shrubs. During the Caragana microphylla growing season from May to October,2.3% of soil total N was mineralized into inorganic N,87% of which was eventually transformed into NO_3~- -N. The results of this study provide great insight for guiding shrub utility and land management in the establishment and development of shrub ecosystems in the Loess plateau.
中文关键词	小叶锦鸡儿 ; 土壤氮矿化与硝化 ; 晋西北黄土丘陵区
英文关键词	Caragana microphylla shrubs net N mineralization and nitrification northwestern Shanxi Loess Plateau
语种	中文
国家	中国
收录类别	CSCD
WOS类目	FORESTRY
WOS研究方向	Forestry
CSCD记录号	CSCD:5887625
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/234845
作者单位	1.山西省林业调查规划院, 太原, 山西 030012, 中国; 2.山西省农业科学院农业环境与资源研究所, 土壤环境与养分资源山西省重点实验室, 太原, 山西 030031, 中国; 3.美国弗吉尼亚理工大学作物土壤环境系, 24061, 美国
推荐引用方式 GB/T 7714	白日军,杨治平,张强,等. 晋西北不同年限小叶锦鸡儿灌丛土壤氮矿化和硝化作用[J],2016,36(24):8008-8014.
APA	白日军,杨治平,张强,&张训忠.(2016).晋西北不同年限小叶锦鸡儿灌丛土壤氮矿化和硝化作用.生态学报,36(24),8008-8014.
MLA	白日军,et al."晋西北不同年限小叶锦鸡儿灌丛土壤氮矿化和硝化作用".生态学报 36.24(2016):8008-8014.