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On the basis of observed pan evaporation data during 1980–2008 at 66 meteorological sites and seven meteorological elements during 1961–2005 at 90 meteorological sites in the upper reach of Yangtze River, the change and its causes of pan evaporation in this region were analysed. The annual runoff changes of seven hydrological sites in this region and the impacts of the pan evaporation changes on water cycle were investigated. The results showed that, according to the characteristics of pan evaporation, the upper reach of the Yangtze River could be divided into three different climate regions. The eastern and western parts in the reach were all the statistically significant decrease regions, located at Qinghai-Tibetan Plateau and Daba Mountain, and they were named RI and RII, respectively. The middle part was the significant increase region, located at Sichuan Basin, named RIII. There were different meteorological elements that resulted in the changes of pan evaporation for the three regions. The decrease of pan evaporation in RI owed to the reduction of solar irradiance and wind speed disturbance. In RII the decrease of pan evaporation was brought about by the significant reductions of multi-meteorological elements, including solar irradiance, wind speed disturbance, near surface and atmospheric humidity. For RIII, the air temperature significantly increased and then the air near the surface and whole atmosphere became dry. As a result, the increase of pan evaporation in this region took place. The pan evaporation change directly influenced the water cycle in the survey reach. The water cycle in RI intensified due to the increases of rainfall and surface runoff, despite pan evaporation decreasing. In RII there were the decreases of three elements, such as rainfall, runoff and evaporation, so that the water cycle in this region weakened significantly. For RIII, the water cycle weakened due to decreasing rainfall and runoff as well as increasing pan evaporation.

The upper reach of the Yangtze River, 4 511 km long from west to east, contains a great amount of water resources of the Yangtze River Basin. This article studies the characteristics of the pan evaporation, the related meteorological variables, and their effects on the pan evaporation, based on the data of the daily pan evaporation (1980-2008) and other meteorological variables (1961-2008). The results show that the linear trend of the pan evaporation has remarkable regional features, i.e., the decrease trend in the southwest and the increase trend in the northeast of the investigated region, and the Yangtze River is approximately the boundary of these trends. The meteorological variables have different effects on the pan evaporation depending on the fact that they are in the category the thermal variables or the dynamic variables. The thermal meteorological variables (i.e., air temperature, diurnal temperature range, and sunshine duration) have positive partial correlations with the pan evaporation, while the dynamic ones (air pressure, rainfall, and relateive humidity) have negative correlations with the pan evaporation. The correlation of the wind speed remains to be investigated.

Evaporation plays an important role in water balance on the land surface. In Northern China, the evaporation series of the recent 115 years was reconstructed on the basis of Thornthwaite evaporation formula. The characteristics of the reconstructed series were analyzed using 10-year running mean filter, power spectrum method, and running t-text of abrupt changes on the paper. The results showed that there were remarkable interannual fluctuations with timescales of about quasi-8-year, 3-4-year, and quasi-2-year, and interdecadal oscillations with timescales of 57.5-year, quasi-23-year, and 11.5-year. Meanwhile, the abrupt changes of the evaporation series were also of interdecadal timescale. Either interannual fluctuations or interdecadal oscillations of evaporation were closely related to variations in air temperatures and precipitation.

Government intervention in transition period is one of the critical influential factors of merger efficiency, and there is much less research in this field. This paper deeply analyzed the effect of government intervention on merger efficiency from the multidimensional perspectives of the executive level of government intervention, transferring of state-owned control right and changing of final controller. This research concluded as follows, resource distribution efficiency of merger market is on the steady increase, however, government intervention has negative effect on company merger & acquisition, and the difference in the intervention extent of the government on the company merger & acquisition leads to the difference in the merger efficiency. With the enforcement of government intervention from the central government to provincial, city and county governments, the merger efficiency is in turn in decrement. The merger efficiency of state-owned controlling right transferring market is not high due to the effect of government intervention, and the transferring performance of state-owned controlling right with the changing of final controller is relatively high.

SWOT method is used to analyze strengths and weaknesses in internal environment and opportunities and threats in external environment of development of agricultural product logistics in Shaanxi Province. The research indicates that the logistic development strategy of agricultural products in Shaanxi Province should bring into full play strengths in traffic, production, labor force, and science and technology. Besides, it is required to overcome weaknesses in information mechanism and management mode. Furthermore, we should take full advantage of domestic and international resources to develop famous, excellent and special products, to achieve high-efficient, rapid, and convenient development of logistics for agricultural products.