| The Juye oversize coalfield is located in between Jining city and Heze city, Shandong province which were divided into Juye coalfield and Liangbaosi coalfield, including seven parts:Yucheng, Guotun, Zhaolou, Longgu, Wanfu, Liangbaosi and Pengzhuang coalfields. The coalfield was found in the 1960s, and a large-scale exploration began in the 1990s; The coal area is up to 1210 km~2, it is proved that the reserves of coal is no less than 5.571 billion tons, at this stage of planning the reserves of coal is 3.096 billion ton except some reserves that could not use temporarily, Because the coal mine area is big, thick of homestead, and circumjacent area is so dense that there are some problems in the eco-geological environment. And they have a large influence on the regional economic, communications, agriculture and other aspects, It is an important to estimate for an ecological and geological environment comprehensive evaluation on Juye oversize coalfield, and benefit for the sustainable development of the region and the Province.The paper have a lot of been studied on the social economy, natural geography, regional geological, hydrogeological condition, engineering geological condition, soil environment characteristics, land resources and vegetation and so on, through the various aspects of the investigation, we have got a lot of valuable scientific accurate and detail data. Through analysis of these data, the paper discussed some problems that may be caused by the coal mining and some damages caused to the eco-geological environmental in details and summarized. And used different evaluation methods for the different problems in regional eco-geological environment in many aspects respectively, especially innovational used the related theory of nonlinear evaluation methods which can effectively avoid the excessive deviation problems caused by subjective factors that exist in the common experience evaluation methods. This paper used the fuzzy set theory to appraise the eco-geological conditions of groundwater in this area, used matter-element theory of extenics to appraise soil eco-geological environment quality in the mine area, used evaluation method based on rough set theory to appraise the ground subsidence situation in the mined-out area , studies show that various evaluation methods, especially creative evaluation methods such as fuzzy sets, the extenics and rough set an so on is feasible and effective, compared to common experiences it is more reliable. The evaluation results provide scientific references for comprehensive development of Juye coalfield and sustainable development of the Juye county. Finally, on the basis of so many researches and evaluations, the paper used Analytic Hierarchy Process to do some current situation evaluations and prediction evaluations for the overall regional eco-geological environment. This paper reached the following conclusion according to deeply and systematic researches:1.This article made evaluation respectively from three aspects ,the earth crust stability, ground deformation and the foundation stability , and on the basis of the evaluation results ,we made engineering geological environment quality evaluation by stacking every evaluation index respectively, and in the end we divided the investigated region into two parts: basic stability (â…¡) and less stable (â…¢), it can reflect the engineering geological environment quality conditions on the whole.2.The groundwater vulnerability evaluation method of DRASTIC was first raised by the U.S. environmental protection agency (EPA) in 1987, this paper did some beneficial exploration by using this method to appraise the groundwater vulnerability of mining area. At the same time, the paper used traditional methods to evaluate groundwater resources and the groundwater environmental quality .In the groundwater ecological environment quality evaluation process, this paper devided the factors into three key aspects: the groundwater resources, groundwater environment quality, and groundwater vulnerability. And innovatively using the fuzzy set theory to consider the related of combination, the paper established a nonlinear appraisal system, and have successfully done the groundwater environment comprehensive evaluation. From the groundwater ecological geological environment quality zoning map we can see that the regional groundwater ecological geological environment problems are severe, the majority area ,about 72.5%,is poor in groundwater ecological geological environment quality, mainly distributed in the central and south half of the area; A less worse area of about 19.0%, mainly distributed in the north-central part; Good area is only about 8.5%, scattered around Yucheng, the west of Wuan and Yucheng, the west of Taipingji of Juye ,and the area around of Liangbaosi.3.This paper first used single parameter success rate method, the synthetic index method and other conventional methods to made evaluation of soil environmental quality. Then, the matter-element analysis method based on the theory of extenics was used to do the soil eco-geological environment quality research, it has built a evaluation model that contains several index parameters for soil eco-geological environment evaluation. And while the weight in this paper were combined both with objective weight which are formed by theoretical study and with subjective weight which is formed by the scientists determination. And through this method, the paper successfully improved the credibility of the evaluation result, And at last used the quantitative number as the evaluation result, which can relatively reflect the real comprehensive level of soil ecological environment quality. Comprehensive evaluation shows: the majority of the region were not affected by soil pollution, clean area accounts for about 11.3%, almost clean area accounts for 50%, light pollution area accounts for about 38.7%.4.Through the investigation and analysis of the mining area of Juye coalfield, this paper considered that the ground collapse problem is one of the most important factors to the regional eco-geological environment. And the ground collapse of mining area evaluation is a highly nonlinear problem, and was formed by several factors, the traditional experience evaluation method often exist some problems because of overweight subjective factors and may not in according with the fact, so this paper used methods based on rough sets theory, comprehensively considered several nonlinear factors ,and has got more objective and reasonable results.5.Based on the analyses of effective factors of surface collapse at goaf fields in mine area, the paper used rough sets theory to make attribute reduction operations on these factors. Research results showed that five attributes after reduction could comprehensively reflect effective factors of surface collapse at goaf fields in mine area of Juye coalfield, and this could offer relative excellent judging index sets for nonlinear predictions in the future.6.Composition of the decision table in rough set theory had great influence on final analysis results. Based on the determined effective factors of surface collapse, this paper constructed decision table of risk assessment on surface collapse by field engineering survey on the spot. The obtained samples were come from different mine fields, with the distribution characteristics of these samples was"homogeneous dispersion, trimness comparability". Due to these two reasons above, the samples obtained here could reflect the situation of the whole sample set and the final generated decision table could include informations of the whole sample set on the greatest degree. The prophetic risk of collapse in the mined-out area is most at dangerous level and above, the sunken risk factor is the highest in such areas below:Liangbaosi, Yuncheng, Guotun, Zhaolou, Longgu, Wanfu mining area , and the facts are serious dangerous; The average subsidence area of mining is about 4.66m, if calculating with theoretical subsidence value 10 mm point for influence boundary point, the area of collapse is about 570.6 km~2 ,the acreage of hydrops area and serious collapse area (considering groundwater depth 5.00m at dry season) will reach 182.6 km~2.7.This paper made comprehensive assessments for ecologic environmental geologic problems of oversized type Juye coalfield by using AHP. We got mathematical platform of comprehensive assessments (AHP), established mathematical model of eco-geological environmental assessments and got comprehensive index as well as vulnerability index of eco-geological environmental quality. In the end we got geological environmental assessment achievements under all kinds of effective factors. The result shows: The ecological geological environment quality in most area is in good degree and sporadic distribution; Prediction shows that the acreage of good area is a little bigger than the poor area. The risk of ecological geological environmental vulnerability is medium fragile degree, and points out that the unreasonable developement of coal resources will make the ecological geological environment change from good quality mainly to poor quality. 8.This paper used methods that based on rough set theory, the fuzzy set theory and the theory of extenics and other such nonlinear methods to consider both the influences of the eco-geological environment factors and the relationships among the various factors. It effectively avoided the subjective factors problems in the weights choices. And the paper successfully established relevant evaluation models, and gave the evaluation results. It provided a feasible innovation idea for the future work on eco-geological environment evaluation.
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