Abstract:Evapotranspiration is an important component of the hydrological cycle, which integrates atmospheric demands and surface conditions. Research on spatial and temporal variations of reference evapotranspiration (ET o ) enables understanding of climate change and its effects on hydrological processes and water resources. In this study, ET o was estimated by the FAO-56 PenmanMonteith method in the Jing River Basin in China, based on daily data from 37 meteorological stations from 1960 to 2005. ET o trends were detected by the Mann-Kendall test in annual, seasonal, and monthly timescales. Sensitivity coefficients were used to examine the contribution of important meteorological variables to ET o . The influence of agricultural activities, especially irrigation on ET o was also analyzed. We found that ET o showed a decreasing trend in most of the basin in all seasons, except for autumn, which showed an increasing trend. Mean maximum temperature was generally the most sensitive parameter for ET o , followed by relative humidity, solar radiation, mean minimum temperature, and wind speed. Wind speed was the most dominant factor for the declining trend in ET o . The more significant decrease in ET o for agricultural and irrigation stations was mainly because of the more significant decrease in wind speed and sunshine hours, a mitigation in climate warming, and more significant increase in relative humidity compared with natural stations and non-irrigation stations. Changes in ET o and the sensitivity coefficient of meteorological variables in relation to ET o were also affected by topography. Better understanding of ET o response to climate change will enable efficient use of agricultural production and water resources, which could improve the ecological environment in Jing River Basin.

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Uniform design methodology and response surface methodology were used to determine the optimum conditions for hawthorn-Yali pear wine. By using uniform design, the effects of fermentation temperature, sugar content, the ratio of hawthorn to pear, soaking time of hawthorn, additional volume of SO 2 , and yeast dosage on sensory quality were investigated, which indicated that the first three aspects were of great significance to the sensory quality. By using three-factor, three-level response surface methodology, a prediction model was established in the form of quadratic polynomial regression equation, with the best processing conditions hereby determined under the conditions of fermentation temperature (25.18°C), sugar content (22.00%), the ratio of hawthorn to pear (21.19:100), and the alcohol degree (11.05 (V/V %)).