Abstract
Rangeland degradation caused by increasing misuses remains a global concern. Rangelands have a remarkable spatiotemporal heterogeneity, making them suitable to be monitored with remote sensing. Among the remotely sensed vegetation indices, Normalized Difference Vegetation Index (NDVI) is most used in ecology and agriculture. In this paper, we research the relationship of NDVI with temperature, precipitation, and Aridity Index (AI) in four different arid rangeland areas in Spain’s southeast. We focus on the interphase variability, studying time series from 2002 to 2019 with regression analysis and lagged correlation at two different spatial resolutions (500 × 500 and 250 × 250 m2) to understand NDVI response to meteorological variables. Intraseasonal phases were defined based on NDVI patterns. Strong correlation with temperature was reported in phases with high precipitations. The correlation between NDVI and meteorological series showed a time lag effect depending on the area, phase, and variable observed. Differences were found between the two resolutions, showing a stronger relationship with the finer one. Land uses and management affected the NDVI dynamics heavily strongly linked to temperature and water availability. The relationship between AI and NDVI clustered the areas in two groups. The intraphases variability is a crucial aspect of NDVI dynamics, particularly in arid regions.
Highlights
Rangelands cover almost 33% of ice-free land globally
When yearly average Normalized Difference Vegetation Index (NDVI), temperature, and precipitation were plotted at the two resolutions, different behaviors were found in these 18 years (Figures 3 and 4)
Show that NDVI is scale dependent. These resolutions show differences, when studying correlation and regression analysis. They are suggesting that medium resolution is more suited for spatial and lagged temporal patterns
Summary
Rangelands cover almost 33% of ice-free land globally. Monitoring rangeland is a key aspect of stopping its degradation. Rangelands management is complex as rangelands are not spatially homogeneous; those with erodible soils and palatable vegetation are more prone to degrade than others. Arid and semiarid rangelands tend to have erodible soils and variable precipitation regimes, making them more sensitive to degradation [3,4]. Different types of rangeland depend on land use, plant communities, soil, and climatic conditions. These include grazed wastelands such as stubble from mainly rainfed cereal crops, other croplands and fallow lands, grasslands, scrublands, and open woodlands [5]. Using remote sensing to monitor these areas and
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
