Multi-index time series monitoring of drought and fire effects on desert grasslands

REMOTE SENSING OF ENVIRONMENT

卷:183

Article

Villarreal, Miguel L.¹  Norman, Laura M.²  Buckley, Steven³  Wallace, Cynthia S. A.²  Coe, Michelle A.⁴ 

[1] US Geol Survey, Western Geog Sci Ctr, 345 Middlefield Rd MS 531, Menlo Pk, CA 94025 USA

[2] US Geol Survey, Western Geog Sci Ctr, 520 N Pk Ave,Suite 102G, Tucson, AZ 85719 USA

[3] Natl Pk Serv, Southwest Exot Plant Management Team, 12661 E Broadway Blvd, Tucson, AZ 85748 USA

[4] Univ Arizona, Sch Geog & Dev, Box 210076, Tucson, AZ 85721 USA

关键词: Time series analysis;    Fractional cover;    Landsat;    SATVI;    NDVI;    Grasslands;    Fire management;    Drought;   

DOI  :  10.1016/j.rse.2016.05.026

来源: Elsevier

【 摘 要 】

The Western United States is expected to undergo both extended periods of drought and longer wildfire seasons under forecasted global climate change and it is important to understand how these disturbances will interact and affect recovery and composition of plant communities in the future. In this research paper we describe the temporal response of grassland communities to drought and fire in southern Arizona, where land managers are using repeated, prescribed fire as a habitat restoration tool. Using a 25-year atlas of fire locations, we paired sites with multiple fires to unburned control areas and compare satellite and field-based estimates of vegetation cover over time. Two hundred and fifty Landsat TM images, dating from 1985-2011, were used to derive estimates of Total Vegetation Fractional Cover (TVFC) of live and senescent grass using the Soil-Adjusted Total Vegetation Index (SATVI) and post-fire vegetation greenness using the Normalized Difference Vegetation Index (NDVI). We also implemented a Greenness to Cover Index that is the difference of time-standardized SATVITvFc and NDVI values at a given time and location to identify post-fire shifts in native, non-native, and annual plant cover. The results highlight anomalous greening and browning during drought periods related to amounts of annual and non-native plant cover present. Results suggest that aggressive application of prescribed fire may encourage spread of non-native perennial grasses and annual plants, particularly during droughts. Published by Elsevier Inc.

【 授权许可】

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