Multifaceted Impacts of Sustainable Land Management in Drylands: A Review

Simulating with a combination of RUSLE GIS and sediment delivery ratio for soil restoration

Erosion by water is the main cause of land degradation. Landscapes degraded by erosion need to be restored in many respects, and particularly in terms of ecosystem services. From an economic and management perspective, care is needed to select priority areas and determine the means to be applied to restore them. Globally, the model most commonly used to produce scenarios for the prevention of soil losses is the Revised Universal Soil Loss Equation (RUSLE). This study of the subbasin of the Sulakyurt Dam Basin in Turkey aims (1) to identify the distribution of soil losses over time and by location, and (2) to grade the priority areas for the prevention of soil losses by means of a simulation. The average potential soil losses in the area under study are estimated at 42.35 t ha^-1 year^-1, and the average actual losses at 39.49 t ha^-1 year^-1. According to the simulation, 27.61% of the study area (2782 ha) is of the highest priority for soil restoration. In our study, forests have the highest soil losses, which is contrary to the natural protection that forests provide against erosion. The high rates are due to the slope, the forest area is very steep. So it is the slope factor that outweighs the vegetation cover factor. Of the forest areas, 41.74% (1766 ha) falls within the areas of highest priority. The study serves as a guide for landscape planning and the determination of erosion risk in restoration efforts, and for identifying the methods to be adopted during the restoration work to reduce the loss of soil.

A framework for separating natural and anthropogenic contributions to evapotranspiration of human-managed land covers in watersheds based on machine learning

Actual EvapoTranspiration (ET) represents the water consumption in watersheds; distinguishing between natural and anthropogenic contributions to ET is essential for water conservation and ecological sustainability. This study proposed a framework to separate the contribution of natural and anthropogenic factors to ET of human-managed land cover types using the Random Forest Regressor (RFR). The steps include: (1) classify land cover into natural and human-managed land covers and then divide ET, meteorological, topographical, and geographical data into two parts corresponding to natural and human-managed land cover types; (2) construct a natural ET (ET_n) prediction model using natural land cover types of ET, and the corresponding meteorological, topographical and geographical factors; (3) the constructed ET_n prediction model is used to predict the ET_n of human-managed land cover types using the corresponding meteorological, topographical and geographical data as inputs, and (4) derive the anthropogenic ET (ET_h) by subtracting the natural ET from the total ET (ET_t) for human-managed land cover types. Take 2017 as an example, ET_n and ET_h for rainfed agriculture, mosaic agriculture, irrigated agriculture, and settlement in Colorado, Blue Nile, and Heihe Basin were separated by the proposed framework, with R² and NSE of predicted ET_n above 0.95 and RB within 1% for all three basins. In the semi-arid Colorado River Basin and arid Heihe Basin, human activities on human-managed land cover types tended to increase ET higher than humid Blue Nile Basin. The anthropogenic contribution to total water consumption is approaching 53.68%, 66.47%, and 6.14% for the four human-managed land cover types in Colorado River Basin, Heihe Bain and Blue Nile Basin, respectively. The framework provides strong support for the disturbance of water resources by different anthropogenic activities at the basin scale and the accurate estimation of the impact of human activities on ET to help achieve water-related sustainable development goals.

Off-Season Agriculture Encroachment in the Uplands of Northern Pakistan: Need for Sustainable Land Management

Agriculture encroachment over alpine pastoral land is posing serious threats to the sustainable use of natural resources and agro-pastoral systems in the upland environment. This study aimed to understand the scenario of agriculture encroachment within a sustainable land management context in Northern Pakistan’s uplands (Buhrawai). Both quantitative and qualitative methodological approaches were used for the primary data collection on the pattern of cropland expansion, cropland productivity, agrochemical inputs, and perceived socio-ecological system. The results showed that off-season agriculture has emerged as a cash-earning livelihood activity, largely adopted by decade-old and influential tenant communities in the study areas. During the last few decades, this off-season agriculture regularly expanded from lower- to higher-elevation (2980–3800 m) areas, and extensively encroached on accessible pastoral areas in the bottomlands. Cultivation of the two major vegetable crops, i.e., peas and potatoes, occurred on a total of 417.4 ha of pastoral land, where pea cultivation predominantly occurred on 367.2 ha and potato cultivation on 50.2 ha of pastoral land. We found that repeated cultivation of the same crops, without crop rotation and land management practices, significantly reduced land productivity with time; the crop productivity was recorded to be the highest in the virgin cultivated land (pea: 1.8 tons/ha and potato: 14.8 tons/ha) and the lowest in the old-cultivated land (pea: 0.6 tons/ha and potato: 8.2 tons/ha). As a result of this trend, farmers are abandoning unproductive agricultural land and subsequently starting cultivation in other marginal areas, even cultivating crops on steeper slopes beyond the permissible level (16°). These findings revealed that farmers have extensively used key pastoral areas for cultivation, and they have deprived landless pastoralists of their traditional grazing land in the uplands. Furthermore, this agriculture encroachment imposed serious pressure on the pastoralists’ livelihoods and the upland ecosystem on which they rely. Therefore, policies and regulations that promote sustainable land management are much needed to ensure socio-economic equity and ecological integrity in the uplands of Northern Pakistan.

The Social Impacts of Sustainable Land Management in Great Green Wall Countries: An Evaluative Framework Based on the Capability Approach

The Great Green Wall Initiative (GGWI) is a pan-African program launched in 2007 to combat land degradation and bring about both ecological and socio-economic benefits in the Sahel. With projects in place on only one-fifth of the targeted land and uncertainty about the extent of positive impacts, there is a need for improved monitoring and evaluation of current projects to inform the design of future projects. In this paper, we focus on the evaluation of socio-economic impacts, drawing on development theory, to relate investments in sustainable land management (SLM) to outcomes in terms of human well-being. We deploy a conceptual model, which draws on both the capability approach to human development and the sustainable livelihood framework. To contextualize the framework to the Sahel, we undertook a literature review of scientific studies of the facilitative social conditions and socio-economic impacts of SLM interventions in four countries: Senegal, Burkina Faso, Niger and Ethiopia. We further refined the framework by examining project evaluation reports of Global Environmental Facility (GEF)-funded SLM projects. Our analysis of GEF projects shows that current monitoring and evaluation pays only limited attention to achieved outcomes in terms of well-being. We briefly discuss the application of the framework to SLM interventions and make recommendations for how it should be operationalized, including recommending more comprehensive measurement of the well-being impacts of these projects.