Based on the monitoring data of 36 meteorological stations in Jiangxi Province from 1960 to 2018, the characteristics of drought change and the correlation between SPEI index and M-K trend test. The results show that the SPEI-12 index showed a slight downward trend, and drought and flood alternated from year to year. The annual drought mainly distributed in the northeast, west and southeast of Jiangxi Province, and most of the drought was global and regional, and the regional drought was more significant after 2000. The seasonal drought occurred in summer and autumn, especially in autumn. The drought degree in spring and winter was light and more frequent in the southern part of Ganzhou. However, after 2001, spring showed an aridity trend, and the SPEI index in summer, autumn and winter showed an upward trend, even easy to cover the province's serious autumn drought. Crop to the affected area and summer and autumn were significantly correlated with SPEI index and summer drought influence on Jiangxi crops than autumn drought. The results can provide reference for drought control and drought resistance in Jiangxi Province.

Conventional methods such as deformation monitoring, laser scanning and ground-based radar have certain limitations in the scene of high slope near the dam of hydropower station, so it is difficult to find the hidden dangers of high slope disasters near the dam in time and early-warning slope accidents. Taking a hydropower station in Jinsha River Basin as the research object, this paper proposes a high slope displacement detection method based on the UAV proximity photography, which mainly includes the UAV proximity photography data acquisition method for accurate path planning, generation of the SFM-MVS 3D model and point cloud model, and point cloud comparison algorithm based on adjacent 3D grid plane. Data acquisition, accuracy analysis and displacement comparison are carried out in the study area. The results show that the accuracy of this method in both horizontal and vertical directions reaches millimeter level, which can meet the needs of large-scale and high-precision displacement detection of high slope near the dam, and has strong scientific research and engineering practical value.

Revealing the characteristics of basin runoff evolution and quantitatively identifying the contribution of driving factors is essential for adaptive water resources management and water security in basins. Based on the measured monthly runoff series from 1960-2015 at the NO.2 hydrological station in the source area of the Ulungur River and the meteorological and human water and soil resources development and utilization image data for the same period, the sliding removal wavelet analysis method, the Mann-Kendall trend test method and the sliding t test method were used to analyze the evolution trend and mutation characteristics of the hydrometeorological elements sequence. The elastic coefficient method based on the Budyko hypothesis was used to identify the contribution rates of climate changes and human activities to runoff change in the study area. The results show that there is a non-significant upward trend in runoff series, a significant upward trend in precipitation series and a significant downward trend in potential evapotranspiration series in the Ulungur River source area; The runoff series changed abruptly in 1995, with the sensitivity coefficients of runoff to precipitation, potential evapotranspiration and subsurface characteristics increasing by 8.8%, 25.0% and 7.8% respectively in the change period 1995-2015 compared to the base period 1960-1994; The contribution of changes in precipitation and potential evapotranspiration and subsurface characteristics parameters to runoff changes are 39.2%, 7.0% and 53.8% respectively. The runoff changes in the study area are driven by a combination of human activities and climatic elements, with human activities being the main driving factors.

Aiming at the shortcomings of insufficient population diversity, easy to fall into local optimum, and slow initial solution speed of intelligent water drops algorithm (IWD), an improved IWD algorithm (IIWD) was proposed, which introduces the Logistic chaotic initialization method and the differential variation operator of the difference evolution algorithm (DE), and improves the neuronal update mode of the self-organizing mapping algorithm (SOM) and introduces it into the sub-update process of the optimal individual of the IWD algorithm. The IIWD was applied to the peak shaving scheduling of cascade reservoir groups. Compared with IWD and DE, the efficiency of the IIWD was verified.

In order to explore the temporal and spatial variation of annual precipitation and the type of precipitation field in Heilongjiang Province, this paper analyzed the precipitation of Heilongjiang Province from 1980 to 2020 using the Mann-Kendall test method, EOF decomposition method, Morlet wavelet analysis and other methods commonly used in modern climate statistical diagnosis. The results show that the precipitation tendency rate in Heilongjiang Province from 1980 to 2020 is 15.52 mm/10 a, that is, the precipitation has a significant upward trend. The precipitation in summer accounts for about 65% of the whole year, and only 3% in winter; Under the influence of topography and climate, precipitation in Heilongjiang Province showed significant spatial differences. As a whole, the south and central regions have higher precipitation, followed by the east, and the west and north regions have lower precipitation. According to the EOF decomposition, the precipitation in Heilongjiang Province can be divided into three modes and six precipitation fields: the first mode indicates that the precipitation in Heilongjiang province is more or less; The second mode showed that the central and northeastern parts of the province had more precipitation, while the southwest and Greater Khingan Mountains had less or opposite precipitation. The third mode showed that the precipitation was higher in the southwest of the province, and less or opposite in the southeast and Greater Khingan Mountains. There were two scale variation cycles of precipitation in Heilongjiang Province, 11-30 a and 3-7 a, with 28 a as the first main cycle.

The problems, such as unreasonable development of small hydropower and the neglect of the river ecological flow demand, can negatively impact the hydrological ecology of the lower reaches and damage the habitat environment of aquatic organisms. Taking the Xiaxiang hydropower station in the Dahuan River Basin of Guangxi Zhuang Autonomous Region as the research reach, carp was selected as the target fish. Based on the suitability curve of carp velocity and water depth, using the habitat simulation, the characteristics of hydrodynamic distribution and carp mass habitat area distribution under 11 flow conditions were analyzed. The results show that the suitable ecological flow of target fish in dry season is 9.38 m³/s, and the minimum ecological flow is 6.25 m³/s. The comparative analysis was carried out by using the hydrology method, and the suitability of the minimum ecological flow was evaluated by three evaluation indexes. The results show that the suitable ecological flow and the minimum ecological flow of the habitat simulation are reasonable and suitable. The research results are of great significance to ensure the ecological environment health of the downstream rivers of small hydropower stations.

Roughness is an important parameter which reflects water transport capacity of water diversion project. The roughness value can be calculated by observing the frictional head loss. However, how to estimate the roughness is always a difficult problem in hydraulics for the new unworked water diversion project. The surface roughness of water conveyance buildings is a vital factor affecting the roughness value. So, this study proposed a surface roughness measurement method relies on hierarchical sampling. Taking a new in-situ reinforced concrete lining tunnel as an example, the statistical distribution of surface roughness and the minimum sample size of tunnel roughness estimation were analyzed. On this basis, the roughness value range of the tunnel project was estimated, which has a certain reference significance for predicting the water transport capacity of the new project and inspecting the construction quality of the lining.

Optimal allocation of water resources is an important method to effectively relieve the contradiction between the supply and demand of water resources in regions. The traditional butterfly optimization algorithm (BOA) has some defects, such as low search accuracy, slow convergence speed, easy to fall into local optimization and can not be directly used to solve multi-objective optimal allocation of water resources problems. It was improved by introducing the methods of fast non dominated sorting, congestion and elite strategy, and the superiority of the ameliorative butterfly optimization algorithm (ABOA) was verified by using ZTD function. Finally, the ABOA was applied to the optimal allocation model of water resources in Handan, and the scheme with the least water shortage was selected as the final scheme from the Pareto front. The Handan water resources optimal allocation in 2035 (p=50%) yielded a total water demand of 2.74 billion cubic meters, a total water distribution of 2.44 billion cubic meters, and the water shortage was 298 million cubic meters, and the water shortage rate was 10.9%. Domestic and ecological water demand could be fully met. However, the primary, secondary and tertiary sectors were still facing water shortages in different regions, which need to be alleviated by water conservation. The research results can provide a new reference for the solution of multi-objective optimal allocation of water resources.

Most existing parameter inversion methods of the dynamic constitutive model parameters do not take the concept of uncertainty into account. Therefore, the adaptive cloud transformation algorithm (AGCT) was combined with RBF neural network (RBFNN) to construct an adaptive cloud neural network parameter inversion model (AGCTNN), which converts the uncertainty concept into quantitative values and better takes into account the influence of the randomness and ambiguity between dam systems on the inversion of dynamic parameters. AGCT was compared and analyzed with three traditional clustering algorithms, K-Means, SOM and DBSCAN, to verify the superiority and feasibility of the algorithms. The inversion analysis was then carried out on engineering examples using two inversion models, AGCTNN and RBFNN. The results show that the positive coupling results of the proposed inversion model are in better agreement with the measured values, and the error range between the measured and inverse values of peak acceleration at measurement points is reduced from 8.73%-25.17% to 2.31%-8.16%, which confirms the reasonableness of the inversion model and the possibility of its application in practical engineering.

It is of great significance to discuss the relationship between ecosystem services and matching status of water and land resources for the sustainable utilization of ecological resources. Therefore, the equivalence factor method, matching coefficient of water and land resources, and coupling coordination degree model were used to reveal the spatiotemporal evolution characteristics of the ecosystem service value, matching status of water and land resources, as well as the coupled coordination relationship between them in China. The results show that the total value of ecosystem services in China increased 2144.45 billion yuan. The overall spatial pattern of the ecosystem service value per unit area was high in the south China and low in the north China, and the ecosystem service value per unit area in all provinces except Shanghai was improved during the study period. The matching coefficient of water and land resources in China continued to decrease, showing a clockwise spatial variation characteristic of first decreasing and then increasing roughly with Qinghai province as the endpoint in space. The coupling coordination degree between ecosystem services and matching of water and land resources in China from 2010 to 2018 first increased and then decreased, and the overall belonged to the basic coordination type, which was in transition. The coupling coordination degree shows the spatial distribution characteristics of high in the south Chin and low in the north China. The results can provide decision-making basis for the policy formulation of coordinating ecological protection and water and land resources utilization.