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• Quantitatively describes the groundwater recharge process for lakes. • Constructed a model for the groundwater table-lake area relationship in groundwater-dependent lakes in arid regions. • Suggested a groundwater depth of 1.73 m to maintain stable lake area within the Hetao Irrigation District. • Constructed model can serve as an effective reference tool for groundwater management and the protection of lake ecosystems. The groundwater table constitutes a significant factor in sustaining the ecosystems of lakes in arid regions. To elucidate the mechanism by which variations in groundwater tables affect lake areas, this paper presents a case study of a typical groundwater-fed lake in China's Hetao Irrigation District. An analytical model correlating groundwater tables with lake areas was developed to simulate and predict the impact of changes in groundwater tables on lake areas. The findings indicate that the analytical model adeptly simulates the lake area dynamics of the groundwater-fed lake cluster (Taerhu lake cluster) from 1998 to 2018, achieving a Nash-Sutcliffe efficiency (NSE) value exceeding 0.6 and a root mean square error (RMSE) value below 0.1 square kilometers. Maintaining a groundwater depth at 1.73 m ensures the stability of the lake area; a decrease in groundwater depth to 1.93 m would result in a 79.5 % reduction in lake area. The model constructed in this study offers a crucial tool for the ecological protection of lakes and groundwater management in arid regions. [ABSTRACT FROM AUTHOR]

• The current paper presents a method for monitoring indicators for desertification hazard assessment. • This research has addressed the major problem of environmental, which is desertification. • The current paper indicated that spatio-temporal variations in the desertification process in the study area have driven by both anthropogenic and natural factors. • Using of GIS environment has improved the conventional map overlay techniques in land management. Desertification is a serious and perilous threat to natural ecosystems. Understanding the spatio-temporal characteristics of this process through the evaluation and monitoring of important indicators appears to be a challenging task. This research was carried out in arid regions of the northeast of Iran, with the objective of assessing desertification intensity and monitoring its progress over time. After collecting the basic data including climate, land use and land cover, roads of access, geology, demographics, pedology, land capability, and drainage network, desertification intensity was firstly assessed using the Iranian Model for Desertification Potential Assessment (IMDPA). Based on the results of the IMDPA model, important desertification indicators were selected and monitored in Geographic Information System (GIS). The results of the model were validated against ground-based data via the non-parametric Mann-Whitney test. The findings of desertification intensity assessment showed a moderate desertification intensity over approximately 41% of the central, northern and northwestern parts of the region. The agriculture criterion along with natural factors such as groundwater level fluctuations, salinity, and erosion had the greatest impact on the severity of desertification. Monitoring important and effective indices (over a 20-year period and in four 5-year intervals from 1995 to 2014) showed that drought, population growth, migration, land-use changes, vegetation degradation, soil erosion, groundwater level fluctuations, deterioration of groundwater quality and expansion of low-yield agricultural lands (2.75% increase in agricultural and residential lands over 2004–2014) led to an increased desertification intensity. Based on the status of desertification, a number of possible management programs were proposed for the study area. Accordingly, the implementation of some land degradation control programs such as replanting vegetation and compatible with salinity and drought are recommended to reduce desertification intensity in the study area. [ABSTRACT FROM AUTHOR]

[Display omitted] • SIF data that characterizes the growth of sandy vegetation is more sensitive. • SIF can well capture the changes in surface moisture and groundwater. • Vegetation growth has a strong correspondence with SM and a relatively weak correlation with TWS. • Vegetation growth in the late period of the mutation year is generally better than that in the early period. • Similarities and differences of vegetation-moisture relationship in four sandy lands. Hulunbuir, Otindag, Horqin and Mu Us are the four greater sandy lands in China. They are typical ecologically fragile areas with limited ability to resist interference and are susceptible to changes in the external environment. With climate change in recent decades, these areas have experienced severe land desertification and decreased groundwater levels. The ecological environment is at risk of further deterioration, and continuous vegetation restoration and management should be adapted to the local climate and maintain the water balance with natural precipitation. This paper combines multi-source satellite observations to explore the relationship between vegetation growth and water supply. The results show four main points. (1) Although the vegetation growth in Otindag and Horqin had degraded before 2010, it improved after 2010. The vegetation growth and soil moisture (SM) of the four sandy lands both generally increased from 2003 to 2016. The SM of the Horqin increased significantly (84% anomaly > 1.4 × 10−2 cm3/cm3). Other than the Hulunbuir, the other sandy lands show a downward trend in terrestrial water storage (TWS), especially the Mu Us declined the most (97% anomaly < −40 mm). (2) Solar-induced chlorophyll fluorescence (SIF) has specific advantages in characterizing the sandy vegetation productivity and water composition changes compared to vegetation index (EVI) or gross primary productivity (GPP). (3) The regional pattern of the vegetation-moisture relationship is mainly affected by the precipitation-driven SM and depends on the types of underlying vegetation functions. (4) Both SM and TWS have approximately one-month persistence in the four sandy lands, especially the Mu Us has the longest persistence (0.94 months and 1.1 months). The persistence in the early period is generally longer than that in the late period, implying that the resilience of water components after the mutation year is stronger than before it. This study provides a scientific basis for the management and restoration of sandy lands. It is recommended that different vegetation restoration and protection strategies should be developed for specific sandy land moisture conditions in arid/semi-arid regions of northern China, which includes the improvement of water use efficiency to maintain soil moisture and the reduction of excessive groundwater uses. [ABSTRACT FROM AUTHOR]

The development of irrigated agriculture is necessary for fulfilling the rising food requirements of the burgeoning global population. However, the intensification of irrigated agriculture causes the twin menace of waterlogging and soil salinization in arid and semiarid regions where more than 75% of the world's population lives. Waterlogging and salinization have direct and indirect effects on plant growth and yield. The damage to plant growth and yield is much serious when these processes occur simultaneously and generally yield reduction is linearly correlated with the salinity level. The control of shallow watertable with irrigation management and installation of drainage systems are suggestible to control the waterlogging and salinization problems of irrigated agriculture. This paper presents an overview of the different aspects of waterlogging and soil salinization and its impact on the food production and sustainability of irrigated agriculture. Conclusions are provided which could be useful for all the stakeholders. [ABSTRACT FROM AUTHOR]