In the black soil area, where soil erosion is severe and the soil is in urgent need of ecological restoration, providing reasonable and practical measures to prevent soil erosion and restore the soil is an urgent issue at present. In this study, nine runoff plots were deployed in Bin County, the core area of soil erosion control, to monitor runoff and soil loss long-term, simulated by the erosion potential method (EPM) for comparison. Studies have shown that soil erosion is strongly influenced by soil conservation measures, land use, and vegetation cover. In contrast, slope, pre-soil moisture content, and soil crusting due to rainfall can affect erosion in a single rainfall event. The most severe soil erosion was in bare land, up to 1093.58 t km⁻² a⁻¹, followed by longitudinal ridge tillage land (751.88 t km⁻² a⁻¹) and cross ridge tillage land (31.58 t km⁻² a⁻¹). The shrublands and mixed forests planted for ecological restoration experienced almost no erosion. The soil loss rate of the cross ridge tillage and ecological restoration plots was much lower than the allowable soil loss rate (200 t km⁻² a⁻¹). Under erosive storms, longitudinal ridge tillage can produce soil loss rates that far exceed those of bare ground. The change from longitudinal ridge tillage to cross ridge tillage on gentle slopes can effectively prevent soil erosion in the study area. The vegetation restoration measures of planting shrubs such as Amorpha fruticosa Linn. are incredibly effective in the ecological restoration of wastelands in black soil areas. For the black soil area after the retreat, the vertical structure of vegetation can be improved by planting shrubs at the bottom, thus achieving a good restoration effect.

In recent years, China’s agricultural water consumption has been high, while water inefficiency has restricted the development of the economy. In this study, we developed an agricultural interval two-stage fuzzy differential water prices model (ITS-DWPM) by incorporating the techniques of two-stage programming (TP) and interval-parameter programming (IPP) based on the differential water price. The ITS-DWPM can link the associated economic penalty attributed to the violation of the preregulated water target and the total system benefit under limited data availabilities (expressed stochastic and interval values); meanwhile, inaccurate water quantity data and dynamic economic data would be resolved. The methodology tended to resolve the complexity of initial water rights allocation problems, incorporating the relevant sectors as well as the agricultural irrigation system construction involved in water management decision. Furthermore, the model takes into account the restrictions on water quantity and price. In addition, multiple decision results were calculated under different states of water shortage. The developed method is applied to initial water rights allocation and agricultural irrigation system construction. The results generated can assist decision makers not only in formulating water rights allocation strategies, but also in balancing the contradiction between economic objectives and water resources control indicators. In 2020, the irrigation water utilization coefficient of each agricultural irrigation area in Hulin City should reach 0.55. Hutou needs to increase its agricultural irrigation channels by at least 4.49%, Shitouhe by at least 4.03%, and Daxinancha by at least 4.49%.

Investigating the impact of different factors on soil and nutrient loss and suggesting viable control measures is currently a significant concern. This study aims to examine the variations in soil erosion, as well as nitrogen and phosphorus loss, in the core area of the typical hilly diffuse Blackland erosion control. To achieve this, runoff plots with slopes of 3° and 5° were set up in the Sunjiagou sub-basin, located in the upper reaches of the Feiketu River. These plots were subjected to various soil and water conservation measures, along with different levels of vegetation cover. This study aims to analyze the soil and nutrient loss patterns and characteristics in each runoff plot during the natural rainfall events occurring between 2020 and 2022. The results show that soil and nutrient losses are highly significantly and positively correlated with rainfall intensity. The RUSLE model demonstrates a better fit for both cross ridge tillage and bare ground. The loss of nitrogen was much more significant than that of phosphorus, and nitrate nitrogen is the main form of nitrogen loss. Nitrogen loss is mainly dominated by nitrate nitrogen (NN), which is easily soluble in water and constantly migrates with runoff due to the negatively charged NN (NN accounted for 45.2% ~ 81.8% of total nitrogen (TN)). In contrast, the positively charged ammonia nitrogen (AN) is more stable in combination with the soil; large losses only occur under severe sediment erosion. Phosphorus is easily attached to sediment, and the high sediment production leads to a more serious loss of total phosphorus (PP) in the particulate state (PP accounts for 72.7% ~ 96.2% of total phosphorus (TP)). Changing longitudinal ridge tillage to cross ridge tillage and planting vegetation with better water retention and sediment fixation as plant hedges can effectively prevent the loss of soil, runoff, nitrogen, and phosphorus.

To lessen the strain on Harbin’s water resources and enhance the environment, it is crucial to analyze the key determining factors for the use of unconventional water resources in the city and to allocate unconventional water reasonably among various industries in the planning year. In this study, a back-propagation neural network (BP neural network) model is used to predict the potential for unconventional water resource utilization in the planning year (2025), a gray correlation analysis model is used to evaluate water-using industries, and finally, an unconventional water resource allocation scheme for the study is used to determine the main influencing factors and determine the weights of key indicators. The findings demonstrate a strong correlation between Harbin’s level of investment and construction, economic efficiency, cost, level of water demand, and social factors, as well as a low level of utilization of unconventional water resources throughout the city.

Reclaimed water is a stable unconventional water resource, improving the utilization rate of reclaimed water and strengthening the allocation of reclaimed water resources are the current important work of cities in China.In this paper, the research on reclaimed water in China is relatively backward, and a perfect allocation scheme of reclaimed water has not yet been formed. According to China 's development pattern and industrial economy, with the goal of most in line with urban development planning and maximizing economic benefits, a set of algorithms for the allocation of reclaimed water in three major water consumption items of municipal miscellaneous, primary industry and secondary industry are set up, and then three representative cities in South China and North China are selected for calculation.Finally, some suggestions are put forward for the development of reclaimed water in China according to the results.