Approximately 50% of the Earth's deserts are covered with stony surfaces, not dunes. The stony surfaces often block or diminish mineral dust aerosol emissions through area fraction and roughness element effects. Incorporating these stone coverage effects is crucial for climate and environmental modeling research. Based on our field observations, this study combined the stone coverage effects into a dust simulation model for East Asia using two regression formulas and some constants. The double regression scheme assumed that the stone roughness density could be derived from the coarse fragment fraction of the SoilGrids 2.0 data set. According to the data set, the stone coverage is higher in Western Mongolia and Dzungaria and lower in the Chinese Gobi Desert and the Loess Plateau. Consequently, the model reproduced fewer dust aerosols in the higher coverage areas and more in the lower coverage areas. This simulation result was consistent with the World Meteorological Organization's current weather reports and satellite aerosol observations. The improved model reproduced the diversity of soil erodibility and was well balanced in performance statistics. This study is the first successful investigation of stone coverage effects on dust storm simulation using a realistic stone coverage map to the authors' best knowledge. Plain Language Summary More than 50% of the Earth's deserts are covered with stones, not dunes. The stony surfaces suppress sand and dust storms in the deserts. Because the mineral dust particles globally influence climate change, investigating the stony surfaces is crucial to climate prediction research. Therefore, we developed a new simulation scheme for sand and dust storms to incorporate the stony surface effects. Formulating the stony surface effects was based on our field observations in East Asia. The global stone map we used was obtained from the SoilGrids 2.0 data set. Our simulation model reproduced fewer dust storms in higher stone coverage areas and more in lower areas. This simulation result was consistent with weather observatory observations in Mongolia and China. Satellite measurements for air pollution also backed up the simulation result. This study is the first successful investigation of the stony surface effects on dust storm simulations using a realistic stone coverage map to the authors' best knowledge.
The rational allocation of the water resources in drylands and the scientific evaluation of their values are important for the regional sustainable development. We estimated the water consumption of each ecosystem in Ejina Oases in the arid area in northwest China based on the water balance equation, then assessed their ecosystem service values (ESVs) using the value per unit area method and the value equivalent factor per unit area method considering the cost of water consumption, respectively, and calculated their water productivities from 1990 to 2015. With the implementation of the ecological water diversion project (EWDP) in 2000, the deciduous broadleaf forest dominated by Populus euphratica had an increasing trend, meanwhile, lakes had a changing process from shrinking and drying up to recovery and expansion from 1990 to 2015. The total water consumption in Ejina Oases decreased from 5.26*10(8) m(3) in 1990 to 4.79*10(8) m(3) in 2000, and then increased continually to 5.97*10(8) m(3) in 2015. The water consumption of forest, grassland and cultivated land hardly changed, while the water consumption of water or wetland changed obviously. The total ESVs estimated using the value per unit area method in Ejina Oases decreased from 1052.6 to 787.3 million yen in the period of 1990-2000, then increased to 1500.6 million yen in 2015, while the ESVs estimated using the value equivalent factor per unit area method decreased from 6368.7 million yen in 1990 to 5892.0 million yen in 2000, then increased to 7139.9 million yen in 2015, and the latter method was more reasonable. The results showed that the EWDP started in 2000 led to the reallocation of water resources and transfer of ESVs among ecosystems, which had obvious performance in the ecological environment and social economy. This study provided a comprehensive view of water use and management, ecological restoration and socio-economic development in this key ecological function zone, and will help decision-makers to formulate the scheme of rational allocation and efficient utilization of water resources in the basin.
Under conditions of ongoing climate warming and increasing anthropogenic impact on land resources, the use of moisture-saving soil-protecting technologies becomes especially important. Snow cover is of great importance for agriculture, as it changes radiation and thermal balance of underlying surface, protecting soil from cooling and winter crops from freezing, accumulates winter precipitation, being the most important source of increasing soil moisture reserves in arid and subarid zones in spring. Winter precipitation accounts for up to 30% of the annual norm. Soil moisture reserves formed with their help take up to 42% in total water consumption for grain crop yield formation during wet summer and up to 75% during dry summer. This article aims to study the effect of different methods of snow retention and snow cover height on the yield of grain crops. An effective method of snow retention is leaving high stubble after harvesting winter and spring crops. Leaving stubble bushes with a height of 0.35-0.40 m and a width of 1.5 m every 4.5 m provides accumulation of a solid snow cover in steppe areas with a height of 0.30-0.35 m, which increases the yield of wheat. Waders provide a more uniform distribution of snow cover than forest strips. Climate change contributes to the fact that snow retention becomes an urgent problem not only in the dry steppe, but also to the north - even in the forest-steppe. Creation of snow retarders was done on Vetelny state farm, located in Balashovsky district in the western part of Saratov region, in the steppe zone, where chernozem soils prevail in the soil cover. In the autumn period, snow barriers were installed, and in the winter period, their effect on snow accumulation was studied. The study of the effect of snow barriers on soil moisture accumulation during the growing season of winter wheat was compared in the zones of dry steppe, steppe and forest-steppe. It was revealed that during regrowth of winter wheat the least amount of productive moisture stocks in 0-1.0 m soil layer was contained in dry steppe 1377 m(3).ha(-1), the highest in forest-steppe zone up to 1841 m(3).ha(-1). Snow retention increased the amount of moisture in the soil in the dry steppe, steppe and foreststeppe zone by 251, 151, 115-131 m(3).ha(-1), or 18, 10, 6-8%, respectively. Thus, rational use of winter precipitation is a significant reserve of agricultural landscape productivity increase, especially in dry-steppe areas.