Haoran Shi’s research while affiliated with Xihua University and other places

Total dissolved gas supersaturation (TDGS) due to flood or hydropower station discharge adversely affects the swimming performance of migratory fish, thereby reducing passage efficiency. This study assessed the swimming performance of bighead carp in an experimental vertical slot fishway under varied slot flow velocities of 0.2, 0.25, and 0.3 m/s after 2 h of exposure to different levels of TDGS water. The results demonstrated that increased TDGS levels and flow velocities significantly reduced the fish passage efficiency. Specifically, passage success rates reached 61%, 48%, 37%, and 37% at TDGS levels of 100%, 110%, 120%, and 130% respectively, at a flow velocity of 0.2 m/s. At flow velocities of 0.2, 0.25, and 0.3 m/s with 100% TDGS water, success rates were 61%, 53%, and 47%, respectively. Moreover, increased TDGS levels and increased flow velocities notably extended the passage time in the fishway. Both TDGS levels and fishway flow velocities significantly influenced the swimming trajectories of the fish. Preferences for flow velocities were notably affected by the TDGS levels, whereas preferences for turbulent kinetic energy were affected by both the TDGS levels and the velocities of the fishway flow. In this study, an evaluation method was developed to assess the adverse effects of TDGS on fish passage efficiency based on the following critical parameters: passage success rate, time, trajectory, and preferred hydraulic factor. This study offers valuable insights for optimizing operations and fishway management to enhance fish protection.

Analysis of crop water requirement and its influencing factors are important for optimal allocation of water resources. However, research on variations of climatic factors and their contribution to wheat water requirement in Xinjiang is insufficient. In our study, daily meteorological data during 1961‒2017 in Xinjiang was collected. Penman–Monteith formula and crop coefficient method was adopted to calculate wheat water requirement. Mann–Kendall mutation test and grey correlation degree analysis were used to investigate variation characteristics and correlation degree between climatic factors and wheat water requirement. The results showed that wheat water requirement ranged from 511 to 548 mm (average = 529.5 mm). Spatial distribution of wheat water requirement in Xinjiang presented a pattern of "southeast > Northwest, east > west". Wheat water requirement in most areas of Xinjiang showed a decreasing trend. During the whole growth period of wheat, the top five climatic factors affecting wheat water requirement in Xinjiang were ET0, Tmax, Tmean, sunshine duration, and Umean. Precipitation and relative humidity negatively impacted wheat water requirement, while reference crop evapotranspiration (ET0), mean wind speed (Umean), mean temperature (Tmean), maximum temperature (Tmax), minimum temperature, and sunshine duration had positive effects. This study provides a comprehensive basis for the decision making of efficient agricultural water use and irrigation measures in Xinjiang.

During the flood season, high dam discharge rates result in total dissolved gas (TDG) supersaturation. This condition causes gas bubble trauma and can lead to fish mortality, which poses a significant threat to downstream river ecosystems. Assessing the ecological risks of TDG supersaturation is a challenge in waterpower-intensive river basins worldwide. Few studies have explored the impact of TDG supersaturation on fish behaviours, such as aggression and memory, which are crucial for feeding, reproduction, and predator avoidance. In this study, behavioural tests were conducted in a T-maze to investigate the effects of acute TDG supersaturation on swimming behaviour, aggression, and memory in medaka (Oryzias latipes). The results demonstrated that medaka exposed to TDG levels of 115% and 130% for 2 h had significantly reduced swimming performance.At TDG levels of 100%, 115% and 130%, medaka activity rates in the mirror arm of the maze in the mirror test were 44.34 ± 12.88%, 40.27 ± 15.44% and 35.35 ± 16.07%, respectively. Similarly, the activity rates of medaka in the active stimulus arm of the maze in the memory test were 50.35 ± 14.75%, 40.76 ± 12.51% and 35.35 ± 18.47%, respectively. The behaviour of medaka changed with increasing TDG supersaturation. These findings contribute to the development of an ecological risk assessment model for TDG supersaturation based on memory and aggression in fish and provide data for developing management strategies to mitigate the adverse effects of TDG supersaturation.

During the flood season, high dam operations for flood discharge result in total dissolved gas (TDG) supersaturation. This condition causes gas bubble trauma (GBT) and can even lead to fish mortality, posing a significant threat to downstream river ecosystems. Assessing the ecological risks of TDG presents a major challenge in water power-intensive river basins worldwide. Limited research has explored the impact of TDG on fish behaviors such as aggression and memory, which are crucial for feeding, reproduction, and predator avoidance. This study investigated the effects of acute TDG supersaturation stress on swimming behavior, aggression, and memory in medaka. Results indicated that Medaka exposed to 115% and 130% TDG supersaturation for 2 hours showed significantly reduced swimming performance. At TDG levels of 100%, 115%, and 130%, medaka displayed activity rates in the mirror arm of 44.34 ± 12.88%, 40.27 ± 15.44%, and 35.35 ± 16.07%, respectively, and in the active stimulus arm of 50.35 ± 14.75%, 40.76 ± 12.51%, and 35.35 ± 18.47%, respectively. As TDG levels increased, both aggression and memory in medaka significantly declined. The findings of this study could contribute to developing a TDG ecological risk assessment model based on fish memory and aggression, providing essential data for ecological management strategies to mitigate the adverse effects of TDG.

Discharged floods containing a large amount of suspended sediment (SS) can lead to total dissolved gas (TDG) supersaturation downstream of dams. The swimming ability of fish may be affected by TDG supersaturation and excessive SS. However, previous studies focused only on the separate effects of TDG and SS, ignoring their combined effects. In this study, juvenile rock carp and grass carp were selected to assess the interactive effects of TDG and SS on fish swimming ability. A totally crossed two‐factorial design (six TDG levels: 100%, 115%, 120%, 125%, 130% and 135%; four SS concentrations: 0, 50, 100 and 150 mg/L) was set, and the critical swimming speed ( U crit ) and the burst swimming speed ( U burst ) were measured. The findings indicated that the swimming abilities ( U crit and U burst ) of both fish species decreased with increasing TDG levels and SS concentrations. Separate exposure to TDG significantly decreased the swimming abilities of the two fish species, whereas separate exposure to SS decreased only the swimming abilities of juvenile grass carp. Juvenile rock carp exhibited weaker swimming abilities than juvenile grass carp in TDG‐supersaturated water. Additionally, the interaction between TDG and SS reduced the swimming abilities of juvenile rock carp and grass carp compared with a separate effect, but this reduction was significant only for the U crit of juvenile grass carp. This study demonstrates that TDG‐supersaturated water containing SS during flooding may result in fish failure through fishways.

When dams discharge floodwaters, the river downstream often becomes supersaturated in total dissolved gases (TDG) and contains high volumes of suspended sediments (SS). Supersaturated TDG and high SS concentrations in water may affect fish physiologically in ways that manifest in swimming performance. Despite increasing awareness of the separate effects of TDG supersaturation and SS, knowledge about their synergistic effects remains unknown. To explore the interactive effects of TDG and SS on the swimming performance of bighead carp, the juveniles were exposed to 100, 110, 115, 120, 125, 130, 135, and 140% of TDG‐supersaturated water with SS concentrations of 0, 50, 100, and 150 mg/L, respectively, and the critical swimming ability speed (Ucrit) and burst swimming ability speed (Uburst) were measured. The results indicated that the swimming ability (Ucrit and Uburst) decreased when TDG levels and SS concentrations increased. TDG and SS did not interact significantly to decrease both Ucrit and Uburst. In contrast, exposure to TDG alone significantly decreased both Ucrit and Uburst, whereas exposure to SS alone decreased only Uburst. In addition, our results suggested that there was a negative linear relationship between TDG and fatigue time. Swimming ability can decline significantly due to high TDG levels (>130%). Therefore, high TDG levels (>130%) should be restricted during reservoir operation to prevent the stress caused by TDG.

Total dissolved gas (TDG) supersaturation, which can be caused by flood discharge, results in gas bubble disease (GBD) in fish and threatens their survival downstream of dams. TDG supersaturation has become a serious environmental problem in the Yangtze River. Few studies have evaluated the effect of TDG supersaturation on fish in natural rivers during periods of flood discharge. To estimate fish tolerance to TDG supersaturation under natural conditions, juvenile Myxocyprinus asiaticus and juvenile Procypris rabaudi were exposed to TDG-supersaturated water for 96 h at various depths (0–0.3 m, 0.3–1.3 m, 1.3–2.3 m and 0–2.3 m) during periods of flood discharge of Dagangshan hydropower station. The results showed that juvenile Procypris rabaudi and juvenile Myxocyprinus asiaticus exhibited obvious GBD signs. An increase in exposure time decreased survival probability of the two species. Deeper water depths can increase the tolerance of juvenile Procypris rabaudi to TDG supersaturation in natural rivers during periods of flood discharge while it cannot improve the survival of juvenile Myxocyprinus asiaticus. Compared with juvenile Myxocyprinus asiaticus, juvenile Procypris rabaudi showed weaker tolerance of TDG supersaturation in shallow water, and juvenile Procypris rabaudi were more vulnerable to TDG supersaturation than juvenile Myxocyprinus asiaticus even if the TDG level (116%) was low.

Total dissolved gas (TDG) supersaturation caused by flood discharge water is becoming a serious environmental problem that threatens the survival of fish. The swimming ability of fish may be influenced by TDG supersaturation. To investigate the effects of continuous exposure to TDG supersaturation on fish swimming ability, we measured the critical swimming speed (Ucrit) and burst swimming speed (Uburst) of grass carp continuously exposed to TDG supersaturation. The Ucrit values of grass carp were 6.34–3.68 body length per second (BL/s) at 100%, 105%, 110%, 115%, 120%, 125%, 130% and 135% TDG, while the Uburst values were 10.2–8.96 BL/s at these TDG levels. The swimming ability (Ucrit and Uburst) of grass carp decreased with increasing TDG levels and was significantly decreased at higher TDG levels (>120%). A swimming ability recovery test was used to investigate the effects of recovery on the swimming ability of grass carp continuously exposed to TDG supersaturation. When grass carp experienced exposures of 115%, 120%, 125%, 130% and 135% TDG, the recovery ratios of Ucrit were 76%–82% and 77%–86% after recovering for 1 and 2 h, respectively, in freshwater (100% TDG). The recovery ratios of Uburst of grass carp were 84%–98% and 95%–97% under the same recovery conditions and TDG levels. The results showed that the recovery ratios of both Ucrit and Uburst increased with the extension of the recovery time. The swimming ability of grass carp provided with a 2-h recovery time recovered almost completely.

The anti-seepage wall project is an important part of the anti-seepage system of water conservancy and hydropower projects, and it is the basic facility and barrier to resist floods and ensure the safety of people's lives and property. This paper analyzes the wireless communication GPRS (General Packet Radio Service) technology. After establishing a mathematical model and determining the optimal sensor deployment scheme, the mesh-type sensor network type is determined, and the overall design scheme of the system is analyzed. The wireless network completes the field information collection and instruction transmission, and transmits the field information to the remote monitoring platform for unified processing. In order to effectively improve the node coverage of wireless sensor networks, a network coverage optimization method based on a hybrid strategy to improve the Antlion algorithm is proposed. The continuity boundary shrinkage factor is used to improve the search traversal of the algorithm and accelerate the convergence speed. Dynamic weight coefficients are introduced during the elitization phase to balance the global exploration and local development capabilities of the algorithm. Combining the precocious convergence judgment mechanism and the dynamic hybrid mutation method, the algorithm can effectively jump out of the local optimum. The comparison experiments on 4 benchmark functions verify the effectiveness of the improved strategy. The water injection test was used to detect and evaluate the integrity and impermeability of the plastic concrete impervious wall. The drilling and excavation verification results confirmed the effectiveness and practicability of the method.