Many discussions on water rights, water pricing or water market have been made on the WWW site associated with the Ministry of Water Resources (MWR) of China. Knowing the recent trends happening in China, authors consulted documents related to and clarified the current status of water usage in China. As a result, the authors found no legal definition of water rights in China. However, water resources charge, water charge and water intake license have been activated. On the other hand, the site allegedly trading water rights in Zhejinag Province, and Yiwu County have worried about a rapidly growing population and lack of water supply for a long time. At the same time, the authors found Yiwu County allowed contiguous Dongyang Couty to divert 50 million tons of water (right) out of the Hengjin Reservoir. This should be called’water lending, ’ rather than ’water trading, ’ and MWR has tried to set new regulations or laws to manage water lending, and is considering to impose a new tax system.

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The accuracy of the climate and weather prediction is indispensable to more effective water resources management. In Asian region, the Asian summer monsoon has a great impact on the people’s lives. The seasonal march of the Asian summer monsoon is still unpredictable even though the monsoon system has been studied for long. Through examining the seasonal march of the wind field at 850hPa, it is recognized that Somali Jet is one of the key factors of forming the Asian monsoon at its initial stage. This study focuses on the Somali Jet formation by seeking its relationship with other meteorological conditions (such as air temperature, wind, geopotential height field) based on the satellite and NCEP/NCAR reanalysis datasets. We derived anomaly for each parameter in the highest season of the Asian summer monsoon and identified some characteristic spatial patterns that have potential relevance to Somali Jet formation, and compared those seasonal march and interannual variability. As a result, it is found that annual variety of early/late seasonal march of each parameter has good corresponding. This led to a following hypothesis on a process of Somali Jet formation : i) atmospheric heating over the western part of the Tibetan Plateau, ii) a formation of the low in lower troposphere (the monsoon trough) as a consequence of the change in upper troposphere, iii) a formation of pressure gradient between the monsoon trough and the anticyclone in the southeastern part of Africa and finally, iii) a generation of Somali Jet.

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This paper presents the dynamic behaviors of large turbidity inflows in the reservoir and countermeasures to reduce the turbidity problem in the reservoir. With a large volume of the current, the turbid current flows down along the bottom of the reservoir, and the return current after clashing the dam contributes much on mixing of the turbid water with surroundings, causing prolonged turbidity in the reservoir.
The mechanism implied possible treatments to reduce the volume of the turbid water. Numerical experiments indicate that successful purging the turbid water by selective withdrawal reduces the turbid water volume as much as 85% and reduces the period of turbid water by 88%. Then, some calculations are conducted to improve the condition of sediment flow in reservoirs. The results suggest that the behavior of sediment flow can be controlled if the stratification condition or the outlet elevation in reservoirs can be changed.

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Using a dataset of soil water content at 4 grassland sites in a high latitude arid region, temperature effect on time domain reflectometry (TDR) measurement was investigated. Values of measured water content gradient against ambient soil temperature show approximately from 0.0005 to 0.002 (m³/m³·°C^–1) . The values vary with location, depth and time, and is empirically modeled by multiple regression analysis using water content and logarithm of saturated hydraulic conductivity. The latter explanatory variable seems to be important as associated with soil texture or specific surface area of the soil. The empirical model is applied to correct measurement error due to the temperature dependence of TDR, and its performance is compared to that of a theoretical model. As a result, it is shown that the empirical model can successfully correct problematic soil moisture variation not only for data used in multiple regression but also for independent data.

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The large-sized model experiment concerning the hydraulic phenomenon of a water and air in a inverted siphon as a drainage pipe was conducted. In this system, it was confirmed that there were two type of flow in closed channel. One is the usual open channel flow with compressed air over the free surface and the other is the two-phase type flow of water and air. There two type of flow were determined by the shape of inlet to a vertical pipe connected to a horizontal pipe. Unsteady bore appeared in the horizontal pipe, the appearance of bore caused by rushing flow increased the air pressure. Through the experiment, we could obtain the fundamental hydraulic characteristics of the flow in an inverted siphon as drainage system.

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To examine the process of evapotranspiration during and after rainfall, observations in a Japanese cypress forest has been carried out in Kiryu Experimental Watershed (5.99ha), south of the Shiga Prefecture, Japan. The leaf wetness sensors, which detect the resistance between two stainless probes, and heat pulse method were used to estimate canopy wetness and sap flow during and after rainfall. The downward (from the atmosphere to the canopy) sensible heat flux was observed with the eddy correlation/energy balance method and interception loss reached 250 W m^-2 in the daytime during rainfall.
Evaporation, transpiration and canopy wetness were simulated with a multi-layer model. Interception submodel was parameterized using the data of canopy wet time observed with leaf wetness sensors and the latent heat flux observed with the eddy correlation/energy balance method. The time series of changes in sensible heat flux were successfully simulated compared with the observation results. Canopy wetness was sometimes overestimated especially in the upper canopy. The total amount of simulated interception loss was underestimated compared with the observation with water balance method, though close to the observation with the eddy correlation/energy balance method.

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Recently, clinical chemistry study suggests that Deming regression or Passing-Bablok regression should be used for seeking linear relation of two measured data instead of linear regression. The author tests these three methods at the cases of a numerical experimentation and daily rainfall estimation problem. The former shows that Deming and Passing-Bablok regressions are superior to linear regression. The latter hardly shows the superiority of any method in accuracy. Above all, considering theoretical aspects, Deming and Passing-Bablok regressions are more suitable then linear regression for analyzing two measured data.

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