干旱区生态环境知识资源中心(Arid): Short-term vegetation loss versus decadal degradation of grasslands in the Caucasus based on Cumulative Endmember Fractions

Arid

DOI	10.1016/j.rse.2020.111969
	Short-term vegetation loss versus decadal degradation of grasslands in the Caucasus based on Cumulative Endmember Fractions
	Lewinska, Katarzyna Ewa; Hostert, Patrick; Buchner, Johanna; Bleyhl, Benjamin; Radeloff, Volker C.
通讯作者	Lewinska, KE
来源期刊	REMOTE SENSING OF ENVIRONMENT
ISSN	0034-4257
EISSN	1879-0704
出版年	2020
卷号	248
英文摘要	Land degradation affects over one-third of the global land area and is projected to become even more widespread due to climate change and land use pressures. Despite being a critical issue for climate change mitigation, biodiversity conservation, and food security, the detection of the onset, duration, and magnitude of land degradation remains challenging, as is early identification of short-term vegetation loss preceding land degradation. Here, we present a new approach for monitoring both short-term vegetation loss and decadal degradation in grasslands using satellite data. Our approach integrates Spectral Mixture Analysis and temporal segmentation, and analyzes dense time-series of satellite observations in three steps. First, we unmix all available satellite observations and aggregate them into monthly composites. Second, we calculate the annual Cumulative Endmember Fractions and examine their piecewise trends among years to determine the onset, duration, and magnitude of short-term vegetation loss and decadal degradation. Third, we attribute a decrease in the green vegetation fraction with a concomitant increase in either open soil, or non-photosynthetic vegetation. We tested our method mapping short-term vegetation loss and decadal degradation in grasslands in the Caucasus Ecoregion using the 2001-2018 time series of MODIS 8-day reflectance data. We found strong patterns of short-term vegetation loss and decadal degradation, mostly in the eastern part of the Caucasus Ecoregion in areas of desert and semi-desert natural vegetation. Short-term vegetation loss episodes (3-9 years) were more common and had greater magnitude than decadal degradation (>= 10 years), especially in steppe regions. On average, 9.3% of grassland area was subjected annually to either decadal, or short-term vegetation loss. Desiccation, i.e., the shift from green vegetation to dry vegetation, was the most prevalent type of change pathway, with green vegetation loss to open soil coming second. Decadal degradation and short-term vegetation loss rates were the highest in dry areas where the potential natural vegetation is sub-shrub deserts, or halophytic, alluvial, and wet lowland forests. Our findings support known general degradation patterns in the Caucasus Ecoregion, but provide better understanding of ongoing processes, by detecting exact location, timing, and magnitude of changes. More broadly, our method advances the monitoring of grasslands by detecting both decadal degradation and shortterm vegetation loss. This flexibility supports adaptive degradation monitoring, aids sustainable land management, and provides new information for carbon stock analyses and biodiversity conservation.
英文关键词	Land degradation Rangelands Spectral mixture analysis (SMA) MODIS Caucasus mountains LandTrendr Landsat Google earth engine
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000568717100004
WOS关键词	SPECTRAL MIXTURE ANALYSIS ; LANDSAT TIME-SERIES ; CONCEPTUAL-FRAMEWORK ; CLIMATE-CHANGE ; TREND ANALYSIS ; SOIL ; IMPACT ; COVER ; REFLECTANCE ; RESTORATION
WOS类目	Environmental Sciences ; Remote Sensing ; Imaging Science & Photographic Technology
WOS研究方向	Environmental Sciences & Ecology ; Remote Sensing ; Imaging Science & Photographic Technology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/326210
作者单位	[Lewinska, Katarzyna Ewa; Buchner, Johanna; Radeloff, Volker C.] Univ Wisconsin, Dept Forest & Wildlife Ecol, SILVIS Lab, 1630 Linden Dr, Madison, WI 53706 USA; [Hostert, Patrick; Bleyhl, Benjamin] Humboldt Univ, Geog Dept, Unter Linden 6, D-10099 Berlin, Germany; [Hostert, Patrick] Humboldt Univ, Integrat Res Inst Transformat Human Environm Syst, Unter Linden 6, D-10099 Berlin, Germany
推荐引用方式 GB/T 7714	Lewinska, Katarzyna Ewa,Hostert, Patrick,Buchner, Johanna,et al. Short-term vegetation loss versus decadal degradation of grasslands in the Caucasus based on Cumulative Endmember Fractions[J],2020,248.
APA	Lewinska, Katarzyna Ewa,Hostert, Patrick,Buchner, Johanna,Bleyhl, Benjamin,&Radeloff, Volker C..(2020).Short-term vegetation loss versus decadal degradation of grasslands in the Caucasus based on Cumulative Endmember Fractions.REMOTE SENSING OF ENVIRONMENT,248.
MLA	Lewinska, Katarzyna Ewa,et al."Short-term vegetation loss versus decadal degradation of grasslands in the Caucasus based on Cumulative Endmember Fractions".REMOTE SENSING OF ENVIRONMENT 248(2020).