The operation of reservoirs has significantly influenced the river ecological system. Upholding the ecological integrity of rivers during reservoir operations has been the focus of research over the years. When the Dahuofang reservoir project started, focus moved to ecological goals to address the Biliuhe reservoir’s environmental issues. The water strategy limits usage for various purposes and outlines the diversion route, complicating Biliuhe operations. In this study, to comprehend the effects of individual water level guidelines and their combined influence on these goals, the Sobol’ sensitivity analysis was introduced as an initial measure to tackle the optimization challenge. The results show that removing the insensitive water levels during specific periods of reservoir scheduling lines and beginning with sensitive water levels for local optimization to identify viable solutions, and then moving to wider optimization, significantly enhances the search efficiency, solution quality, and operational speed compared with an exhaustive search without any preceding steps. This sensitivity analysis technique is crucial for fine-tuning multi-objective reservoir operations.

Enhancing crop production in the saline regions of the Yellow River Delta (YRD), where shallow saline groundwater is prevalent, hinges on optimizing water and salt conditions in the root zone. This study explored the effects of various physical methods on soil water and salt dynamics during the cotton growing season in these saline areas. Three approaches were tested: plastic film mulching (FM), plastic film mulching with an added compacted soil layer (FM+CL), and ridge-furrow planting (RF). The HYDRUS-2D model (Version 3.02) was used to analyze changes in soil water and salt content in the root zone over time. The results showed that subsoil compaction significantly lowered salt build-up in the root zone, especially in the top 20 cm. Film mulching was crucial for reducing water loss in the Yellow River Delta. Crop transpiration increased by 7.0% under FM and 10.5% under FM+CL compared to RF planting. Additionally, FM+CL reduced soil salinity in the top 10 cm by 11.5% at cotton harvest time compared to FM alone. The study concludes that combining film mulching with a soil compaction layer is a promising strategy for local farmers, addressing soil water retention, salt management, and boosting cotton yields.

Laizhou Bay, a semi-enclosed bay, is prone to storm surges from cold waves due to its geographic and environmental characteristics. This study uses satellite data, in situ measurements, and the MIKE numerical model to analyze storm surges along Laizhou Bay’s coast under no-dike conditions. It examines the surges caused by cold waves with different intensities and directions. This study provides the storm surge disaster risk levels along Laizhou Bay’s coast. The results show that the maximum sustained wind speed during cold waves is distributed between the NW and NE. The NE wind direction causes the most severe storm surge along Laizhou Bay. Under NE-directed cold waves with level 12 wind, the maximum risk areas for Level III and IV are approximately 1341 km² and 1294 km², respectively. Dongying, Shouguang, and Hanting exhibit large Level I and II risk zones. The maximum seawater intrusion distance along the Kenli coast is about 41 km. The coastal segment from Kenli to Changyi is most severely affected by storm surges. It is recommended to effectively maintain and heighten seawalls along this segment to mitigate storm surge disasters caused by strong NE winds.

The grazed grasslands of Inner Mongolia offer a critical research setting for studying the impacts of long-term grazing on soil, hydraulic, vegetative, and meteorological variables, and potentially contribute to examine threshold responses to grazing activity or climate dynamics in colder Eurasian temperate grasslands. The dataset consists of long-term observations of soil temperature and moisture, as well as other related parameters across three scales: pedon, field, and catchment scale. This includes: i) At the pedon scale, data collection was conducted on five sites: long-term grazing exclusion since 1979 (UG79), short-term grazing exclusion since 1999 (UG99), continuous grazing (CG), heavy year-round grazing (HG), and moderate winter grazing (WG), from May 2004 to August 2008. Profiled soil moisture at depths of 5, 20, and 40 cm was continuously monitored using theta-probes, while soil temperature at depths of 2, 8, 20, 40, and 100 cm was monitored using Platinum ground temperature probes. Since 2016, newly automated monitoring instruments were also used for continuous monitoring of soil temperature and moisture at depths of 10, 30, 50, 70, and 100 cm at the UG79, UG99, and CG sites. ii) At the field scale, during the growth period from 2004 to 2008, a regular sampling grid (about 100 points) was established in all five sites using differential GPS and UTM systems. Soil water content, water drop penetration time, shear strength, and hydraulic conductivity were measured once per week/month. At the beginning, soil organic carbon concentration, bulk density, soil texture, and plant parameters were also taken at each grid point. iii) At the catchment scale, a field sampling scheme was designed, using land use and soil type as stratification variables. A total of 30 sampling points were selected. At each sampling point, detailed soil surveys were conducted to measure soil profile characteristics, including soil colour, texture, structure, and chemical elements. Additionally, some soil hydrological properties were recorded on site. This dataset offers critical insights into the factors influencing livestock carrying capacity in Mongolian grasslands. The integration of these data types can substantially enhance our understanding and management of these ecosystems.