TY  - JOUR
T1  - Spatial patterns of long-term vegetation greening and browning are consistent across multiple scales: Implications for monitoring land degradation
AU  - Murthy, Karthik
AU  - Bagchi, Sumanta
Y1  - 2018/08/01
PY  - 2018
DA  - 2018/08/01
N1  - https://doi.org/10.1002/ldr.3019
DO  - https://doi.org/10.1002/ldr.3019
T2  - Land Degradation & Development
JF  - Land Degradation & Development
JO  - Land Degradation & Development
JA  - Land Degrad Dev
SP  - 2485
EP  - 2495
VL  - 29
IS  - 8
KW  - climate change
KW  - grazing management
KW  - restoration ecology
KW  - Sen's slope
KW  - time series analysis
PB  - John Wiley & Sons, Ltd
SN  - 1085-3278
M3  - https://doi.org/10.1002/ldr.3019
UR  - https://doi.org/10.1002/ldr.3019
Y2  - 2021/09/10
N2  - Abstract Understanding spatial?temporal patterns of terrestrial vegetation response to climate change (long-term greening/browning) is important for developing strategies to mitigate degradation. Semiarid rangelands are especially susceptible to degradation, which challenges wildlife conservation and human livelihoods that depend on livestock production. In the cold-arid Trans-Himalayan ecosystem (northern India), temperature is increasing, and it is also becoming progressively wetter. Yet, counter-intuitively, there are widespread concerns over degradation. We evaluated whether greening/browning patterns in long-term satellite-derived vegetation indices (normalized difference vegetation index [NDVI]) are consistent across different spatial and temporal scales using 6 datasets: MODIS (250 m, 500 m, 1 km, and 5.5 km), SPOT 1 km, and GIMMS 8 km. Results indicate browning in the spring and greening in late summer. Location of hotspots of degradation (browning) was broadly consistent across spatial scales (10?2?102 km2) and were found in regions with warmer temperature and at higher elevations. Broadly, the spatial/temporal pattern of browning does not coincide strongly with location and timing of human land use via livestock grazing. This geographical and seasonal context indicates that vegetation response may be more strongly related to climate than to human land use (overgrazing). Importantly, the dynamic nature of greening/browning, across space and time, is not captured by composite annual metrics (sum-NDVI, max-NDVI, and mean-NDVI). This reiterates the importance of both intraannual and interannual assessments. Location of hotspots indicates that degradation occurs in a spatially contiguous manner, but these are not stationary and instead shift with seasons. Overall, the results show that evaluating the consistency of greening/browning trends across different spatial/temporal scales is critical for understanding and managing vegetation degradation.
ER  -