According to the complex adaptive systems theory, tourist destinations may be regarded as complex adaptive systems formed by multiple adaptive agent interactions and composed of an agent system, tourist attraction subsystem, tourist service facility subsystem, and external environment system. This paper explores the spatial evolutionary progress of the Southern Anhui tourist area. The period 1979 to 1990 comprised the formation stage of spatial agglomerates, during which tourist attractions centering on Huangshan Scenic Area and Jiuhuashan Scenic Area were gradually exploited and formed scale agglomeration; tourism spatial structure began to show the characteristics of agglomeration development, and Gini indexes of the number of tourists and tourism revenue increased significantly from 0.26 to 0.29, and from 0.33 to 0.35, respectively. From 1991 to 2008, the system experienced a growth stage in which Huangshan Scenic Area and Jiuhuashan Scenic Area were further developed with improved tourist service facilities. Rapid development of Xidi-Hongcun Scenic Area and establishment of Fantawild Tourist Area promoted the formation of more spatial agglomerates with larger scales; Gini indexes of the number of tourists and tourism revenue presented fluctuating changes, reaching low points of 0.15 and 0.25 in 2000 and 0.12 and 0.22 in 2007, respectively. From 2009 to the present day, the system has remained in a blowout-development stage, during which non-linear interactions among agents are strengthened; various emerging development factors generate cultural tourism, vacation tourism, rural tourism and other new tourism products jointly with traditional development factors. New tourism products form a large number of new spatial agglomerates that are interconnected, accelerating the spatial flow of tourists and tourism revenue and reducing the differences in tourism development levels within the region; Gini indexes of the number of tourists and tourism revenue declined steadily from 0.17 and 0.23 in 2009 to 0.12 and 0.15 in 2016.

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The urban planning industry has always been concerned about conserving and developing historic cities in a sustainable and balanced way. However, unreasonable planning and accumulative effects brought by rapid urbanization prevent the conservation of small-scale famous historic and cultural cities. Taking Tingchow county as an example, this paper focused on sustainable development and the Historic Urban Landscape Approach, and determined the urban functions and specific tasks of various planning of its ancient town with the help of public opinions. This paper mainly aimed at providing guidance on urban decentralization from two perspectives. Firstly, it compared the types of land use and its ratio among famous cities of similar scales, and results showed that it is advisable to reduce three-class residential land use and unnecessary administrative functions. Secondly, it estimated the moderate resident population in different degrees of development, and calculated the upper limit of resource space bearing capacity (REBC) of scenic spots under the guidance of sustainable tourism. Results showed that it is recommended to decentralize and resettle 20%~30% of the resident population, and to control the tourist population below 12,000 per day. As the preliminary work of planning, this paper focused on the scientific planning and availability of decentralization, and reflected an expectation for the mode of public participation and quantitative planning.

Multiple runoff connections for groundwater supply and water quality evolution mechanisms were disclosed using hydrochemistry, multivariate statistics, stable hydrogen and oxygen isotopes, and inverse hydrogeochemical modeling in a multilayer groundwater system in a north China coal-mining district. Groundwater quality was mainly influenced by dissolution and weathering of carbonate, silicate, gypsum, halite, and fluorite, as well as cation exchange. Sulfate enrichment in the Carboniferous limestone aquifer may be due to pyrite oxidation, while gypsum dissolution and sewage contribute sulfate to the Quaternary alluvium. The Ordovician limestone groundwater is hydraulically connected to the other two aquifers. Incongruent dissolution of dolomite occurs when the Ordovician limestone water contacts the Carboniferous aquifer, while evaporation occurs when the Ordovician limestone water migrates upward through fractures to the Quaternary aquifer.

In order to understand the source of groundwater inrush and its hydrogeochemical evolution path truly, determine the evolution characteristics and development trend of water cycle, and effectively solve the problem of water disaster in mining area. In this paper, Jiaozuo mining area, a typical large water mining area of North China type, is selected as the study area. Taking the Ordovician aquifer in the study area as the research object, the Ca2+ hydrochemical equilibrium model of Ordovician limestone water system is established by analyzing the characteristics of concentration gradient field and the relationship between the hydrochemical ions (Ca2+、K++Na+、Mg2+、Cl-、SO42-、HCO3-) and TDS in the mining area, it made a systematic study on the characteristics of Ordovician limestone water circulation, and analyzed the recharge, runoff and discharge characteristics of groundwater in different areas of the mining area. The results show that the Ordovician limestone water in the Jiaozuo mining area has a weak leaching effect in the north and southwest, but a strong leaching effect in the southeast, which shows a runoff characteristic from the north and southwest to the southeast.