Purpose:Long-term irrational use of mine resources leads to soil erosion,the reduction of cultivated land area and the destruction of the ecosystem.To make rational use of mineral resources and restore and control the geological environment of mines,the northwest of Hunan Province is taken as the research object.Method:The methods are as follows:By considering eight evaluation factors of three evaluation types(population density,surface slope,rainfall,engineering rock group,geological structure,mine area,geological disaster,and forest coverage rate),the expert evaluation weight was evaluated,and Q value was obtained through calculation.The innovation was to carry out local mine geological environment evaluation by using vector polygon method and GIS analysis.Based on geographic information system(GIS)technology,the mining environment of each district and county in the study area was graded.Result:The results showed that the mining environment in the northwest Hunan region was generally evaluated intuitively.Significance:It could provide a certain reference basis for mine environmental management and ecological restoration in northwest Hunan Province,and provide theoretical basis for other mine evaluations.

Carbon ion beam irradiation (CIBI) is a highly efficient mutagenesis for generating mutations that can be used to expand germplasm resources and create superior new germplasm. The study investigated the effects of different doses of CIBI (50 Gy, 100 Gy, 150 Gy, 200 Gy and 300 Gy) on seed germination and seedling survival, seedling morphological and physiological traits of an elite centipedegrass cultivar Ganbei. The results showed that irradiation greater than 50 Gy cause inhibition of seed germination, and the semi-lethal dose (LD50) is around 90 Gy for CIBI treated seeds of Ganbei. A carbon ion beam-mutagenized centipedegrass population was generated from Ganbei, with irradiation dosages from 50 Gy to 200 Gy. More than ten types of phenotypic variations and novel mutants with heritable tendencies mainly including putative mutants of stolon number, length and diameter, of internode length, of leaf length and width, of leaf chlorophyll content, of stolon growth rate, of aboveground tissue dry weight, of sward height were identified. While the total sugar content of the plants from irradiated seeds showed no obvious change in all treatments as compared to the control, the crude protein content displayed significant reduction at a high-dose treatment of 200 Gy. Genetic polymorphism was detected in mutagenized centipedegrass population using SSR-PCR analysis, suggesting that CIBI caused alteration of larger fragments of the DNA sequence. As a result, a preliminary batch of mutants was screened in this study. In summary, carbon ion beam mutagenesis is an effective way for developing centipedegrass germplasm with wider variation, and treating seeds with CIBI at a dosage of ~100 Gy could be effective in centipedegrass mutation breeding.

Macro- and micronutrients are both important for growth, nodulation and nitrogen (N2) fixation of soybean, especially when this species is grown under continuous cropping. In China’s continuous soybean systems nutrient uptake and transport as well as diazotrophic N2 fixation had been found to be severely hampered by the incidence of diseases, insect pests or exudates from roots and microorganisms which can be overcome by increased soil nutrient concentrations. In this paper results from a three-year field experiment are presented that was conducted to study the effects of different levels of macronutrients (N, P and K) and micronutrients (Zn, Mn, B, Mo and Mg) on the yield of soybean under continuous and rotation cropping. The results showed that compared to the unfertilized control the application of N fertilizer can increase yields of continuous soybean by 98%, of P by 89%, of K by 26%, and of Zn, Mn, B, and Mg by 17%, 13%, 1% and 15%, respectively.