干旱区生态环境知识资源中心(Arid): Addition of Nitrogen Increases Variability of Vegetation Cover in an Arid System with Unpredictable Rainfall

Arid

DOI	10.1007/s10021-019-00396-4
	Addition of Nitrogen Increases Variability of Vegetation Cover in an Arid System with Unpredictable Rainfall
	Seymour, Colleen L.1,2; Milton, Suzanne J.2,3; Altwegg, Res 4; Joseph, Grant S.2,5; Dean, W. Richard J.2
通讯作者	Seymour, Colleen L.
来源期刊	ECOSYSTEMS
ISSN	1432-9840
EISSN	1435-0629
出版年	2020
卷号	23 期号:1 页码:175-187
英文摘要	Addition of nitrogen (N) to rangeland that has been degraded through overgrazing or drought can hasten vegetation recovery. Additional N may influence temporal stability of vegetation cover, however, and change species composition. Potassium (K), by contrast, may help plants survive dry periods, increasing stability. Plant longevity also influences cover stability, but few studies have investigated effects of additional N or K on relative representation of species' longevities within plant communities. In a semi-arid shrubland, we manipulated N and K in a 2 x 2 factorial experiment (treatments were addition of N, K, K and N, or control) in 12 plots, monitoring vegetation cover and plant species composition over 20 years (1998-2018). We assessed above-ground cover, stability of cover, and changes in community composition. Although responses to additional nutrients might be expected to be muted in this arid system where water is limiting, treatments differed significantly in cover, temporal stability, and species composition. N was associated with greater cover, but with lower stability of cover. Once nutrient addition and lifespan had been accounted for, stability was higher for transects with greater species richness at the start of the experiment. Short-lived species increased and long-lived species decreased in N plots. Additional K increased stability of short-lived species' cover and moderated changes in species composition associated with additional N. Although N can increase cover, it is also associated with greater variability, which is particularly relevant given expected increases in rainfall variability with climate change. The moderating effect of K suggests that it may assist in restoration of areas that have experienced high N addition owing to past management practices.
英文关键词	community composition diversity and stability long-term ecological research nutrient addition/supplementation principal response curves rainfall variability restoration ecology semi-arid rangeland
类型	Article
语种	英语
国家	South Africa
收录类别	SCI-E
WOS记录号	WOS:000515864600013
WOS关键词	PLANT DIVERSITY ; ARBUSCULAR MYCORRHIZAE ; GRAZING INTENSITY ; SPECIES-DIVERSITY ; FERTILIZATION ; SOIL ; AVAILABILITY ; PRODUCTIVITY ; KAROO ; BIODIVERSITY
WOS类目	Ecology
WOS研究方向	Environmental Sciences & Ecology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/314379
作者单位	1.Kirstenbosch Res Ctr, South African Natl Biodivers Inst, Private Bag X7, ZA-7735 Claremont, South Africa; 2.Univ Cape Town, DST NRF Ctr Excellence Percy FitzPatrick Inst Afr, ZA-7701 Rondebosch, South Africa; 3.SAEON, Arid Lands Node, Kimberley, South Africa; 4.Univ Cape Town, Stat Ecol Environm & Conservat Dept Stat Sci, PVT Bag, ZA-7701 Rondebosch, South Africa; 5.Univ Venda, SARChI Chair Biodivers Value & Change, Dept Zool, Sch Math & Nat Sci, Private Bag X5050, ZA-0950 Thohoyandou, South Africa
推荐引用方式 GB/T 7714	Seymour, Colleen L.,Milton, Suzanne J.,Altwegg, Res,et al. Addition of Nitrogen Increases Variability of Vegetation Cover in an Arid System with Unpredictable Rainfall[J],2020,23(1):175-187.
APA	Seymour, Colleen L.,Milton, Suzanne J.,Altwegg, Res,Joseph, Grant S.,&Dean, W. Richard J..(2020).Addition of Nitrogen Increases Variability of Vegetation Cover in an Arid System with Unpredictable Rainfall.ECOSYSTEMS,23(1),175-187.
MLA	Seymour, Colleen L.,et al."Addition of Nitrogen Increases Variability of Vegetation Cover in an Arid System with Unpredictable Rainfall".ECOSYSTEMS 23.1(2020):175-187.