Exploring resources and environmental carrying capacities at the county level: A case study of China's Fengxian County.

The data regarding resources and environmental carrying capacities (RECC) are not only the basis for realizing regional sustainable development, but also the core links for major function-oriented zoning practices, which include specific partitioning schemes of spatial units with various geographical functions. Previously, relevant studies were mainly based on the evaluations of single factors. However, the realization of regional function-oriented spatial zoning practices based on comprehensive assessments of RECC has been neglected. This study presented an evaluation index system for RECC based on nine aspects, in accordance with the evaluation elements of the major function-oriented zoning programs which were in place and the characteristics of the study area. Then, by using subjective and objective comprehensive weighting methods, the basic elements were finally integrated, and an accurate spatial distribution pattern of the RECC in China's Fengxian County was obtained. In addition, based on the construction of a three-dimensional spatial conceptual model, this study was able to finally obtain four specific types of functional partitions in the study areas, and proposed specific development proposals according to the different types of functional zoning from a systemic perspective. It was observed that the RECC had been decreasing from a central built-up area to the surrounding townships, and the spatial distribution patterns were distinctly scattered. In addition, the townships with smaller land scales had more obvious advantages in the RECC. However, fluctuating upward trends were observed after the lowest thresholds had been reached as for the medium or above medium scales. At the same time, in terms of the correlations between the population levels, and gross values and the RECC, fluctuating characteristics were observed. The correlations with the latter had presented S-shape curves and inverted U-shape curves, respectively. Finally, the optimized expansion zone located in the north-central region had taken the greatest percentage among functional zoning classifications, followed by the basic competitive zone in the southwestern section. However, the main construction zone accounted for the smallest proportion, at only 2.065%. Therefore, based on these results, it was concluded that there were certain fluctuating correlations between the RECC and total population levels, economic levels, and land scales. Moreover, the RECC evaluation results were found to gradually decrease after rising to the thresholds under the comprehensive effects of the various factors. This study combined the data of the conceptual model with the RECC evaluation results, in order to obtain a potential geographical functional zoning program for the study area. The results of this study are expected to provide a new analysis perspective for the scientific and sustainable development of small-scale geographic units. Moreover, on the basis of this study's comprehensive evaluations of the RECC, the directions of regional development can be further clarified.