Ecological Effect Law Of The Integrated Management In The Karst Rocky Desertification Regions

Aiming at the practical conditions in karst rocky desertification regions of the Southwestern China, The paper chooses six small catchments, including Shiqiao small catchment in Bijie (karst plateau mountain and upper reaches of Wu Jiang), Wangjiazhai and Yangchangdong small catchments in Qingzhen (karst plateau basin),Dingtan small catchment in zhenfeng (karst plateau gorge) ,Longba small catchment in Zunyi (middle reaches of Wu Jiang), Lizishui small catchment in Yanhe (lower reaches of Wu Jiang), and on the basis of the small catchments units. The paper adopts geomorphology,water and soil conservation theory,probability statistics, ecology theory, and pedology etc. to monitor, evaluate and analyze the law of ecological effect from different landforms, different reaches of river and different ecological environment. In the end the paper bring forwards that make rational use of resources and ecological environment are obviously improved from small catchments to karst of the Southwestern China.Ⅰ. Under the different landforms, because of different basic rock, bare rock rate, slope and factors created by men,the modulus of soil erosion of karst plateau mountain is above than karst plateau basin and karst plateau gorge. The average thickness of soil erosion showed: plateau mountain>plateau basin>plateau gorge. On the time succession, plateau mountain showed increase trend, plateau basin and plateau gorge sometime increase and sometime reduce. The quantity of illumination increased follow the height. The average quantity of illumination in south slope are bigger than north slope, herbaceous and bush biological quantity are followed that. The average air temperature is very complicated, temperature's day range showed basin bigger than mountain and gorge. The air relative humidity showed: plateau gorge>plateau mountain>plateau basin, but on the time succession, they all showed increase trend. The soil temperature in summer are reduce follow the deep increase, but in winter they are increased. The surface soil's(5cm) temperature showed: plateau gorge >plateau mountain>plateau basin, but in 20cm it's showed plateau basin and plateau gorge higher than plateau mountain. The recover speed of plant diameter, size and cover rate showed: plateau gorge>plateau mountain>plateau basin. But plateau basin and gorge are better than plateau mountain in community height, herbaceous and bush biological quantity. The species variety showed: plateau gorge > plateau mountain > plateau basin; degree of uniformity showed: plateau basin>plateau gorge>plateau mountain; degree of superiority showed: plateau mountain>plateau basin>plateau gorge. The soil physical and chemical property showed that plateau basin better than plateau gorge and plateau mountain.Ⅱ.Under the different catchment environment, the modulus of soil erosion in middle reaches of Wu Jiang is smallest, but in upper reaches of Wu Jiang is most. The average thickness of soil erosion showed: upper reaches of Wu Jiang>lower reaches of Wu Jiang>middle reaches of Wu Jiang. The level of soil erosion is increased follow the grade of rocky desertification increase, and under the different land use, it is showed: farmland>shrub and grass land>forest land. The average air temperature is negative related to the average height.The average quantity of illumination showed: middle reaches of Wu Jiang>lower reaches of Wu Jiang>upper reaches of Wu Jiang. The air relative humidity is direct ratio related to annual rainfall, and it is showed: lower reaches of Wu Jiang>middle reaches of Wu Jiang>upper reaches of Wu Jiang. On the time succession, air relative humidity are all increase trend. No matter in which deep, the soil temperature's day range are all showed reduce trend, and upper reaches of Wu Jiang is best. The depth of soil is negative related to the soil temperature's day range. The community height and average plant diameter are showed: lower reaches of Wu Jiang>middle reaches of Wu Jiang>upper reaches of Wu Jiang, and on the time succession, they are all increased. The vegetative cover rate, herbaceous and bush biological quantity are all showed: middle reaches of Wu Jiang>lower reaches of Wu Jiang>upper reaches of Wu Jiang. In a word, biological effect in lower and middle reaches of Wu Jiang better than upper reaches of Wu Jiang. The physical property of soil in upper reaches of Wu Jiang is best, differ not evidently between middle reaches of Wu Jiang and lower reaches of Wu Jiang. The chemical property of soil showed upper reaches of Wu Jiang better than lower reaches of Wu Jiang better than middle reaches of Wu Jiang.Ⅲ.Under the different ecological environment, the average annual rainfall showed: Qingzhen>Yanhe>Huajiang>Zunyi> Bijie. The average quantity of illumination showed: Zunyi>Qingzhen>Yanhe>Huajiang>Bijie. Huajiang dry and heat gorge ecological environment's heat condition is highest, but in Bijie it is lowest. The years average temperature and≥10℃accumulate are all showed: Huajiang > Yanhe > Zunyi >Qingzhen> Bijie. The average vegetation cover rate showed: Zunyi > Huajiang > Qingzhen > Yanhe > Bijie. The difference about air relative humidity is not evident. The upper land biological quantity showed: Qingzhen>Huajiang>Yanhe>Zunyi> Bijie. The physical property of soil showed that the environment of Qingzhen and Bijie better than the environment of Yanhe and Huajiang better than the environment of Zunyi. The chemical property of soil are complicated.