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Abstract: Degradation in arid rangelands is an on-going concern, as they appear to be trapped in a vicious circle of desertification–marginalization–impoverishment. Recent theoretical developments in dryland research strive to provide keys to understanding linked social-ecological systems and land management. One approach, the desert-syndrome, depicts the socio-ecological evolution of drylands as being determined mainly by ecological factors. A second approach, the adaptive management paradigm, acknowledges the existence of socio-ecological systems in drylands which are considered to have adapted to a given political–economic context and a given range of economic and ecological variability. This paper proposes a conceptual framework integrating both approaches in order to point out supplementary important drivers of the socio-ecological evolution of drylands systems, especially rangelands at the global economic and political scale. The analysis is broadly conducted from a political ecology and co-evolutionary perspectives and discusses three main factors: (1) world-wide application of western-based paradigms in resource management and their effect on rangelands, (2) the fossil-fuel based Green Revolution, and (3) capitalist institutions used to regulate agricultural trade and the corresponding tools and policies. The marginalization of arid rangelands is avoidable, but requires real changes in the current general political and economic rationale under which resources are allocated. [Copyright &y& Elsevier]

Abstract: Science is frequently touted as the solution to dryland management problems, yet most management decisions are, by necessity, based primarily on expert knowledge and experience. This paper describes an integrated framework for organizing, synthesizing, and applying our growing understanding of aridland ecosystems using a flexible, multi-objective assessment, monitoring, and management approach. The framework is dual-purpose: (1) to coordinate the use of existing tools, resources, and diffuse knowledge, and (2) to facilitate the integration and application of new knowledge as it is developed. In particular, this framework must facilitate the integration of new knowledge about linkages among landscape units across scales. The framework includes five elements: (1) an ecological site-based approach for categorizing land based on soils and climate, (2) a repository for organizing existing data and knowledge about each ecological site, (3) conceptual models that organize information on the impacts of management and climate variability, and protocols for (4) assessing and (5) monitoring key ecosystem attributes fundamental to a variety of management objectives. Within this framework, basic and applied research are explicitly linked to management of arid and semi-arid ecosystems to more effectively articulate research questions and set research priorities. [Copyright &y& Elsevier]

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. [ABSTRACT FROM AUTHOR]