| Black soil region is an important commodity grain production base in China. The total amount of grain production in the black soil region can be said that to be related the stable operation of the supply in Chinese grain market. Therefore, the region has an irreplaceable role in the protection and implementation of national food security strategies. Known as the Chinese grain production "regulator" reputation.The black soil region of Northeast China is more suitable for temperate continental climate, abundant rainfall, enough light and temperature production potential to make the soil organic matter content in the surface layer of 20 cm.Fertile soil suitable for agricultural development.However, more extensive production management mode has been ignored. It has resulted in the decrease of organic matter content and soil microbial activit y in the unit area. Construction with continuous expansion and the loss of cultivated land resources is serious due to the rapid development of urbanization in the black soil region. Industrialization, increasing the size of the population, residents quality of life continue to improve and urban function taste of the continuous uplifting factors leading to the decline of soil growing environment. In some areas, even the phenomenon of farmland, sustainability of resources in black soil faced with severe challenges.The black soil area is widely distributed in Heilongjiang Province. Grain yield per unit area is important to consolidate and improve the grain strategy of the province. As an important factor affecting the quality of cultivated land, the gully ero sion is the rapid development of the land surface. The quality of the cultivated land,which is severely reduced. Clear region of black soil erosion ditch total and spatial distribution pattern, gully erosion varies with elevation, slope and other natural conditions for understanding erosion gully development process. It is important to formulate effective measures to improve the soil endowment of cultivated land resources in black soil region, and to stabilize the grain supply of the whole country.Heilongjiang Province, Baiquan County is located in the intersection area of Xiaoxing’anling mountains and Songnen Plain, in black soil region of fertile soil zone. The terrain is in the northeast of China. The erosion gully of cultivated land has experienced the stage of natural development, the deterioration of human disturbance and the improvement of erosion gully. It is representative to study the occurrence, development and its impact on the ecological environment in the black soil region. In this paper, the research scope of Baiquan County in the northeast of Heilongjiang province. Based on RS and GIS technology, using SPOT and high resolution satellite remote sensing data source,to carry out quantitative analysis of the dynamic change of erosion gully. A preliminary study on the change of spatial pattern of erosion gully,the rule of topographic differentiation and analysis of influencing factors.In order to lay the foundation for future research in the region. The main contents and conclusions are as follows:(1) From 2008 to 2013, the number of gully erosion in the study area increased significantly. From 2502 to 3712, an average annual increase of about 15, the total length from 6.42 × 10~6 m to 8.59 × 10~6 m, the average length of the trench by 2565.2m reduced to 2314.62 m. But the township amount of erosion ditch has the difference, the largest increase is Xingnong village of erosion gully, followed by Xinghua village, Fengchan village, Dazhong village, Shangsheng village. In contrast, Sandao town, Ainong village, Fuqiang town, Xinsheng village, Xingguo village erosion gully density decreased from the number. From the change of erosion gully density, the villages and towns were slightly different. Gully density is the biggest change in Xingnong town, followed by Xinghua village. On the contrary, the Guofu town and Xingguo village has a decreasing trend, gully density is constant for Ainong village, Fuqiang town, Sandao town. Erosion ditch changes devour cultivated area(1442.61hm~22-1502.45hm~22), damage to the change of cultivated land area(2320.33hm~22-3132.19hm~22), who has the same growth situation, however, significant regional differences, phagocytosis of arable land is the most serious in Baiquan Xinghua village. Destroying cultivated land is the most serious Xingnong town, engulfing farmland and increase ratio of 0.42%. Destroyed arable land increase ratio was 1.15%, Guofu town cultivated land swallowed up with minimal damage and phagocytosis of cultivated land reduction ratio 0.74%, damage of cultivated land reduction ratio is 0.33%. Gully erosion in the cultivated land distribution majority, damage to arable land is particularly serious. Through time nodes defined in 2008 and 2013, density of erosion were 1486.94 m/km~2 facility, and 2150.81m/km~2(cultivated land), erosion density respectively 165.96m/km~2 facility, and 173.83m/km~2(grassland), gully density have decreasing trend(others). Land use structure has obvious influence on soil erosion intensity, with arable land area is increased and the woodland, grassla nd area acceleration the reduction of the gully erosion development.(2) According to this study, the gully horizontal and vertical variation and slope direction, slope height. About 2008-2013 years, erosion gully with layered distribution in the vertical direction. At the same time, the gully density has the same trend with the increase of altitude appears to increase first and then decrease "V" trend. In the height of 250-260 m, the maximum erosion gully density variation peak. Indicating a sensitive degree in this altitude soil reached the maximum height of the environment is relatively fragile. As a turning point in the erosion intensity, elevation area, ecological protection shall be valued. From the time series the change in altitude below 230 m gully density is higher than that of 230 m remained unchanged. With the increasing of the altitude, the two curves farther away, density increasing. In 2008-2013 years, gully density has the same variation that changed with the increase of slope increased first and then decreased trend in peak parabola form. In the slope interval of 3°-4°, density were 370.64m/km~2- 572.80m/km~2. In the slope interval of 0°-4°, erosion gully density growth rate in 2013 than in 2008. In the slope interval of 4°-6°, erosion gully density decreased in 2013 than in 2008. In the slope interval more than 6°, in 2008 and 2013, the density change of gully density was basically the same. In the slope interval more than 5°, the density of erosion channel decreases gradually, and the density cha nge of erosion channel is close to 0. These phenomena show that the altitude range erosion gully formation and change more influenced by slope length, catchm~2ent area, the influence of slope shape, rather than slope. In 2008-2013, the difference of the density of the erosion gully in the eight slopes is obvious. In addition to East and northeast slope, the slope gully erosion has the trend of increase, especially the west slope and the southwest slope increased more significantly. Erosion gully density has the trend of transfer from the east to the west, and sunny slope than that of shady slope, the southern slope is larger than that of the north slope, the southwest slope is greater than that of the northwest slope.(3) In this paper, the SPSS20 platform is used to analyze the correlation of elevation, slope and other topographic indices. Combined with land use data to explore the impact of single terrain factors on the change of erosion gully density.The results show that the change of the erosion groove density is closely related to the altitude, and the slope of the ground is closely related to the slope. In 2008 and 2013, the peak value of erosion gully density is 250-260 m. Taking this as a dividing point, there is a positive correlation between the altit ude and the erosion gully density at the point of demarcation point. Above the dividing point, there is a negative correlation. R2 is 0.87152 and 0.79201. Time series is the starting point of the study(2008) and the end point(2013). In the slope interval of 3°-4°, the peak value of erosion gully density. The slope of 3°-4° degree can be used as a watershed to affect the density of erosion gully. Under this, slope and erosion gully density showed a positive correlation. This is above, for a negative correlation, R2 is 0.9325 and 0.82101. The adjustment of land use structure has a significant impact on the change of erosion gully density. The increase of cultivated land and the decrease of forest land and grassland make the density of erosion gully increase. |
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