A ground-based lidar observation was carried out in the northwest of China to validate the space-borne lidar CALIOP on 23 - 25 March 2009. Combining backscatter profiles of the ground-based lidar and CALIOP, lidar ratio (extinction to backscattering ratio) was retrieved for 532nm and 1064nm wavelengths by using performance function that minimizing the difference between the ground-based lidar and CALIOP for backscattering coefficient. The correlation coefficients between them were 0.98 for 532nm and 0.95 1064nm, respectively. Using the retrieved lidar ratio, the color ratio and aerosol optical depth (AOD) were calculated. The observed aerosols and clouds were classified into three groups (boundary layer dust, free tropospheric aerosol and cirrus cloud) according to a relationship between color ratio and 532nm-backscattering coefficient. We also validate the backscattering coefficient for CALIPSO level 2 data. The result shows that it is underestimated by 21 % compared to this study.
Xinjiang is an agricultural region in arid climate zone of western China. 58.9% of the river water and 23.1% of the groundwater are used to irrigation regions for agriculture. The water for natural ecosystems decreases constantly. The water utilized for human being and for nature is conflicting. For irrigation water it is existed that high water consumption with low economic return. The water utilization efficiency is 52.6% and the return for per cubic meter water is only 0.15 US Dollar. There are four serious ecological problems related with the improper water utilization in Xinjiang, i.e., the land desertification, the soil secondary salinization, the lake drying and water quality worsening and the vegetation degeneration. In this paper, five countermeasures for sustainable water utilization are presented.