<abstract xmlns="http://www.w3.org/1999/xhtml"><p>Proper management of natural ecosystems is not possible without the knowledge of the health status of its components. Vegetation, as the main component of the ecosystem, plays an important role in its health. One of the key determinants of vegetation health is its resilience in the face of environmental disorders. This research was conducted in parts of the Namakzar-e Khaf watershed in Northeast of South Khorasan Province with the aim of quantifying the vegetative resilience on behalf of the ecosystem health in response to long-term precipitation changes. First, the annual precipitation standardization was performed during a thirty-year period by the SPI method. Then, the average variation in TNDVI index obtained from the Landsat satellite images was examined and the resilience was tested by calculating the four effective factors (amplitude, malleability, damping and hysteresis). According to the results, the amplitude in the survey period was 6.04% and the vegetation has had different values of damping over the years. The most prominent example of vegetation resilience occurred between 1986 and 1996, with malleability of 0.7 and damping of zero. Vegetation in this period, after the elimination of drought effects (1986), has not only returned to the amount of vegetation of reference year with severe precipitation (1996) but also increased by 0.25%. This increase, as the index of hysteresis, has been presented for the first time in the ecosystem health discussion quantitatively in the present study. A set of quantitative calculations showed that despite reduced annual precipitation and drought events, the vegetation has been able to maintain its resilience, which indicates the health of vegetation in the studied ecosystem.</p></abstract>

Proper management of natural ecosystems is not possible without the knowledge of the health status of its components. Vegetation, as the main component of the ecosystem, plays an important role in its health. One of the key determinants of vegetation health is its resilience in the face of environmental disorders. This research was conducted in parts of the Namakzar-e Khaf watershed in Northeast of South Khorasan Province with the aim of quantifying the vegetative resilience on behalf of the ecosystem health in response to long-term precipitation changes. First, the annual precipitation standardization was performed during a thirty-year period by the SPI method. Then, the average variation in TNDVI index obtained from the Landsat satellite images was examined and the resilience was tested by calculating the four effective factors (amplitude, malleability, damping and hysteresis). According to the results, the amplitude in the survey period was 6.04% and the vegetation has had different values of damping over the years. The most prominent example of vegetation resilience occurred between 1986 and 1996, with malleability of 0.7 and damping of zero. Vegetation in this period, after the elimination of drought effects (1986), has not only returned to the amount of vegetation of reference year with severe precipitation (1996) but also increased by 0.25%. This increase, as the index of hysteresis, has been presented for the first time in the ecosystem health discussion quantitatively in the present study. A set of quantitative calculations showed that despite reduced annual precipitation and drought events, the vegetation has been able to maintain its resilience, which indicates the health of vegetation in the studied ecosystem.

Quantifying the Vegetation Health Based on the Resilience in an Arid System

Department of Desert Studies, Faculty of Natural Resources and Geosciences

Department of Geography and Ecotourism, Faculty of Natural Resources and Geosciences

Institute of Forest and Rangeland, Agricultural Research, Education and Extension Organization (AREEO)

Ekológia (Bratislava)

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

{"article-title":"Quantifying the Vegetation Health Based on the Resilience in an Arid System"}

Proper management of natural ecosystems is not possible without the knowledge of the health status of its components. Vegetation, as the main component of the...

Quantifying the Vegetation Health Based on the Resilience in an Arid System

Publié en ligne: 20 mars 2018

Pages: 32 - 41

DOI: https://doi.org/10.2478/eko-2018-0004

Mots clés
ecosystem health, resilience, hysteresis, quantitative study, remote sensing

© 2018 Abolfazl Ranjbar et al., published by De Gruyter Open

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Quantifying the Vegetation Health Based on the Resilience in an Arid System

Publié en ligne: 20 mars 2018

Pages: 32 - 41

DOI: https://doi.org/10.2478/eko-2018-0004

Mots clésecosystem health, resilience, hysteresis, quantitative study, remote sensing

© 2018 Abolfazl Ranjbar et al., published by De Gruyter Open

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.

Mots clés
ecosystem health, resilience, hysteresis, quantitative study, remote sensing