Resumen de Detailed land use transition quantification matters for smart land management in drylands: An in-depth analysis in Northwest China
Da Lü, Guangyao Gao, Yihe Lü, Feiyan Xiao, Bojie Fu
Due to the lack of smart land management strategies, the rapid expansion of cultivated oases usually results in water imbalances and land degradation in drylands. Management strategies require an in-depth detection of the modes and mechanisms of local land use change. In this study, to detect the process and spatial pattern of land use change and quantify the spatial relations between oasis expansion and the sources of water and human disturbances, enhanced analysis of land transition matrix and location relationship-based spatial analysis were conducted from 1990 to 2015 in the middle reaches of the Heihe River Basin (M-HRB), a typical arid inland river basin in China. The results indicated that cultivated land and desert together accounted for more than 90 % of the study area. In the M-HRB, cultivated land expansion was an obvious process of land use change. Most of the new cultivated land was reclaimed from desert, but the conversion of grassland to cultivated land was the dominant signal of systematic land transition. Swap changes gradually became the main land transition process from 1990 to 2015. The cultivated land showed a close spatial relationship with land and water resources availability, which also constrained the distribution of cultivated land expansion (i.e., within 200-1400 m of human settlements and within 1000 m of water courses or ditches). The quantification results can be used to facilitate smart land management strategies towards sustainable development in the M-HRB. The methods used here can be adapted to other dryland areas for land change detection that supports sustainable land management.
