Artificially excavated surfaces are common in construction project lands, and classification of them provides a basis for establishment of calculation methods for soil loss, as well as a technical support for controlling soil loss on them. Taking water erosion areas of eastern China as test background, and by field investigation of numerous kinds of construction projects located in different regions, including northeastern black soil areas, northern rocky mountainous areas, southwestern rocky mountain areas and southern red soil regions, the characteristics of artificially excavated surfaces and soil loss properties on them were analyzed, and a reasonable classification system proposed. According to the system, excavated surfaces are firstly classified into two categories, namely homogeneous surfaces and heterogeneous surfaces, in terms of texture and material composition. Then the surfaces are classified into confluence-impact and non-confluence-impact surfaces according to influences of confluence above excavated surfaces. Moreover, in terms of the periods for excavated surfaces exposed to air, surfaces are further classified into stable and non-stable types. At last, the application of the proposed classification system in prediction of soil loss was introduced. In general, our classification system not only overcomes limitation of the current classification for project slopes, but also supplies a basis for promotion of calculation models and methods for soil loss. In addition, the system can also be convenient to popularize and promote in grass-root units for soil and water conservation.

Based on the data of temperature, precipitation and runoff time series from 1960 to 2010 in the Kaidu River Basin, this paper revealed the regional climate and runoff variation characteristics by using the Mann-Kendall trend and abrupt change test, R / S method, linear regression and moving average methods. The results showed that the temperature, precipitation and runoff in the Kaidu River Basin presented an increasing trend with a growth rate of 0.027 ℃/ a, 0.863 mm/ a and 0.625 m³ / a, respectively. The corresponding years of abrupt change were 1993, 1986 and 1996, respectively. In the mountainous area, both temperature and precipitation increased most remarkably. Under the warming climate, the average annual, spring, summer and autumn temperature in the oasis area increased more obviously than those in the mountainous area, but in the oasis area, winter temperature increased more significantly; the precipitation in mountainous area increased more significantly than that in the oasis. Inthe past fifty years, the runoff of Kaidu River Basin had increased by 9.96 ×10⁸ m³, which had a great effect on industrial and agricultural development, daily life and ecological sustainable development of Kaidu River Basin.

Production and construction activities have led to profound changes in occurrence of soil erosion newly arising in production and construction areas. Studies of basic issues in soil erosion are of great significance to sediment control and improvements of on-site and surrounding ecological environment. Therefore, theories and methodologies should be developed to provide scientific guidance for erosion control and soil & water conservation planning in production and construction project areas. This paper summarizes the present research status of soil erosion in production and construction project areas from various aspects including basic concept, research methods, influencing factors, laws of runoff and sediment production; meanwhile, we analyze some of the problems in previous studies, looking forward to supplying reference for studies of related fields in the future.