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In order to reveal the unsafe factors in the whole life cycle of the water diversion open channel in the dry and cold areas in western China, it is necessary to avoid frequent diseases of open channel in this area, which brings great losses to society and economy. In this paper, for the western dry and cold regions unique climatic and geological conditions, according to the Code for Design of Irrigation and Drainage Canal System Structures and combined with the expert consultation and the previous team’s study on characteristics of open channel diseases in this area, this paper established the safety index system of diversion channel and used the gray Euclid theoretical model to evaluate the safety of the whole life cycle. This paper used IAHP to solve the weight of each index, used gray Euclid association theory to determine the correlation between the indicators and finally got the relative gray Euclid weighted correlation degree of diversion channel safely sort. Taking four open channel sections in the dry and cold areas of western China for an example, the paper applied the gray Euclid model to evaluate the safety. The conclusion was in agreement with the actual situation. The research result shows that the model is effective and practical for the safety evaluation of the open channel in western China and it can provide an important basis for the safety management of open channel. [ABSTRACT FROM AUTHOR]

To deeply understand the quantity, quality, spatial distribution characteristics and the representative of cultivated land of national standard farmland in western China at macro scale, it is very important to set up and improve the monitoring system of cultivated land quality in the whole country. This paper, based on the database of farmland classification and national standard farmland in western China (12 provinces, municipalities and autonomous regions), gives a analysis of the quantitative distribution characteristic of national standard farmland of the western region in gradation (quality) and on a secondary zone of the standard farming system. The paper then analyzes the spatial distribution features of standard farmland based on GIS and conducts inspection, definition and statistical tests for the representative of national standard farmland. Results show that: (1) In the view of quantitative distribution characteristics, national standard farmlands of the western China were distributed across all the gradations 4-15, but exhibited great differences in each gradation, such as more than half of them concentrated in 8-12 gradation. The distribution of national standard farmland in the 4, 5, 14, and 15 grades was less. Furthermore, national standard farmlands of the western China are unevenly distributed in the secondary zone and have not covered 28 secondary zones of the standard farming system. Therefore, there exists cultivated land but no national standard farmland in five secondary zones such as Daxing'an Mountains region and so on. (2) From the spatial distribution characteristics, national standard farmland is uniformly distributed on the whole, but there is a significant spatial difference and there exist excessive concentration phenomena in six secondary zones. Thus, the data presented suggest that we should adjust and optimize the monitoring sample plot layout of national standard farmland in western China, according to a comprehensive analysis of the testing results and the distribution characteristics. [ABSTRACT FROM AUTHOR]