| Since the Three Gorges Dam took on the task of water storage, the whole Three Gorges reservoir area has experienced a rise in reservoir level, reservoir resettlement and many other significant events. Due to the changes of two types of data-reservoir water area and local population size, which can have an important impact on the geological environment in the Three Gorges reservoir area, large-scale geological environmental changes occurred. This article mainly focuses on the temporal and spatial variation of land cover in Badong which is located in the Three Gorges reservoir area. Simultaneously, through the analysis on geological factors and demographic datum in study area, the relationships among temporal and spatial variation of land cover, geological factors and demographic datum can be obtained.ln this way, a relational model based on organic and inorganic environment in Badong region can be established and new ideas for future geological environment reaseach can be provided.The experiments in this article were done in Badong County. With pre-processing, classification and calculation on remote sensing data, contour data and stratigraphic data for a long time in the study area, series of remote sensing image classification results and elevation, slope, aspect datum can be obtained. Firstly, series of remote sensing image classification results can be extracted and the changes in the relationships among those classification types can also be analyzed. Secondly, the demographic datum and series of remote sensing image classification results are combined together in order to analyze the relationships between the changes in classification types and demographic datum. And then, series of remote sensing image classification results and stratigraphic datum are combined together in order to analyze the relationships between the changes in geological environments and strata properties in Badong. Finally, the remote sensing image classification results and geological factors which can be calculated from contour datum are combined together in order to analyze the correlations between them. By analyzing and researching on those issues, those following conclusions can be reached:1. Changes of cities and towns of the subject areaThe paper found that the changes of cities and towns of the subject area displayed a regular pattern, as described as follows. Between1996and2008, the total area of cities and towns of the subject area displayed an expanding trend. The total area of cities and towns expanded in pace with the population of the subject area and is expected to expand with the growing population in the future. Meanwhile, the total area of cities and towns expands in pace with the increase of water area within the subject area. However, this change didn’t present itself instantly but did so two years later. So, there was a kind of two-year delay, indicating that the cities and towns were built nearby water. The strata of the cities and towns were mainly made up by brand new stratum and Badong stratum, with the former’s area decreasing obviously between2002and2006while the latter constantly increasing. The two groups of stratum are expected to expand continuously. The area of city and town is between200meters and400meters in altitude and within the scope of between18.02°and25.58°slope. The distribution area of due north aspect is the largest and is expected to further expand with the expansion of the city and town area. The above condition resulted from area featured by the mountain topography, water-system-covered low altitude and the maximum distribution area within the scope of between18.02°and25.58°slope.2. Changes of land-cover of the subject areaIn the paper, land cover mainly refers to forest cover and cultivate field. The paper found that the changes of land cover of the subject area displayed a regular pattern, as described as follows. Between1996and2008, the total area of cultivated filed displayed an expanding trend.Although cultivated field expanded in pace with the growth of the population of the subject area, the change didn’t present itself four years later than the expansion of the population. So, there was a four-year delay. The cultivated field was mainly located in the brand new stratum, Badong section stratum and Jialingjiang section stratum. Between1996and2008, there displayed general conformity between the area changes of major strata and total area. That’s to say, as the total area of cultivated field expands, the filed area in these three sections of strata is expected to increase continuously. The cultivated field is between800meters and1000meters in altitude, and within the scope of between18.02°and25.58°slope. The southeastern aspect accounts for the largest distribution area and is expected to expand with the increase of cultivated field.With the expansion the cultivated field, vegetation has been encroached constantly. That was why the total area of plant area between1996and2008displayed a dropping trend. The vegetation was mainly located in the strata of Shaximiao temple section, Luoreping section and Xiejingshi section. Between1996and2008, there displayed general conformity between the area changes of major strata and total area. That’s to say, as the total area of vegetation reduces, the vegetation in these three sections of strata tends to drop. The vegetation is between1200meters and1400meters in altitude and within the scope of between18.02°and25.58°slope. The northwestern aspect accounts for the largest distribution area and is expected to reduce as vegetation area drops. The above condition resulted from the high altitude of main distribution of vegetation due to the damage of low-altitude vegetation incurred by human’s increasing deforestation and cultivation of arable fields.3. Changes of subj ect water areaThe paper found that the changes of water area displayed a regular pattern, as described as follows. Between1996and2008, the total area of the subject water area displayed an expanding trend. In the long term, as the project of Three Gorge Water Reservation was completed, water area would reach its maximum level in2010. But from the time scope of the paper, water area tended to expand and remained generally steady between2004and2006. The water area is between0to200meters in altitude, and within the scope between0°and18.02°slope. The even aspect accounts for the largest distribution area and is expected to further expand as water area expands. The reason was that the subject water area was mainly affected by the Three Gorge Water Reservation Project.In conclusion, the subject area displayed a series of geologic environment changes between1996and2008, as a result of the destructive impact by human behavior on the geologic environment of the subject area. |
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