The Technology Study Of Vegetation Recovery In The Limestone Region In Taihang Mountain In Hebei

In allusion to the problems of the limestone region in Taihang mountain in Hebei: the soil was dry and poor, the soil depth was thin and the cover rate of vegetation was low, through investigation on the spot and farm experiment in Daqing mountain in Beishuiyu village in Mancheng county, studied the technology of vegetation recovery in the limestone region in Taihang mountain. It can be concluded that:1. Through measured the water content of soil in different soil depth in different gradients , sloping directions and soil thickness of the separate slope terrace in the limestone region in Taihang mountain. It's found that the smaller the gradients of the separate slope terrace, the stronger the water and soil maintenance;the bigger the gradients, the smaller the difference of water maintenance between slope facing south and north;the smaller the gradients, the smaller the difference of water content between terrace and hillside, but in a trend, the water maintenance of terrace was stronger than hillside.2. Through measured the water content of soil in different overlay modes, soil depth, it's found that the difference between film and straw overlay modes was small in water maintenance;different sloping directions and soil depth were not important to the water maintenance in soil;the water maintenance in the terrace that had been overlay was stronger than the terrace that had not. So the two above points proved that, in the limestone region in Taihang mountain, constructed the separate slope terrace and taken overlay on ground in 5-20 gradient, the water maintenance can be improved, compared to the hillside.3. Through investigated on the spot, it can be concluded that, compared to the un-controlled region, for increasing the water content and nutrition in soil and biomass, the region of controlled four years and seven years had great progresses, the characters and nutrition of soil improved, the biomass increased, vegetation had been resumed effectively. 4. it can be concluded that, by farm experiment, for improving the height and the stem's number, chemical fertilizer was better than organic fertilizer, the combination of chemical and organic and chemical only can produce the fructification ahead of time, for increasing the fresh weight of peanut (not conclude fructification) in midterm, the combination of chemical and organic was better, for increasing the quantity of saturationfruits s the weight of saturation fruits of peanut, the combination of chemical and organic was better than the separate of them. Analyzed the content of nutrition in soil, found that the content of available N in soil had not changed notably in different disposals, for increasing the content of available P in soil, chemical fertilizer was better than organic fertilizer, for increasing the content of available K in soil , the combination of chemical and organic was better than the separate of them, for increasing the content of organic matter in soil, organic was better than chemical, it can be concluded that for increasing the nutrition content in soil, the combination of chemical and organic had great progresses.5. Through investigated the vegetation communities in the experiment region, The preponderant species were educed by integrated appraisement, the adaptability of Platycladus orientalis> persimmon^ Vitex negundovar> wild jujube^ Cynodon dactylon^ Themeda triandra var.japonica and other wild species was better than others, bringing-in plants, such as almonds guava, torch tree^ castor-oil plant and so on, their physical characters were better than others, give attention to both ecological and economic benefits through the combination of wild and bringing-in species.6. It can be concluded that, compared to the un-controlled region, for increasing the nutrition content and physical characters of soik improving the water maintenance of soil and the characters of litter > enhancing the biomass and the cover rate of vegetation, the controlled and closing hill had great progresses. Among these, for fertilizing soil and improving physical characters, persimmon was better than arborvitae in controlled;for improving the water maintenance of soil and the characters of litter, shrubbery was excellent, the follow was arborvitae and persimmon;for enhancing the biomass and the cover rate of vegetation, shrubbery was better than tussock in closing hill, persimmon was better than arborvitae in controlled. It can be concluded that the combination of the controlled and closing can resume the vegetation effectively, practise the combination of arbon shrub and herbage in the middle and bottom of hill that the depth of soil was deep, practise the combination of shrub and herbage in the top of hill and the place that the gradient was steep.