Potential Analysis of Inefficient Garden Land and Residual Forest Land Remediation in Comprehensive Land Remediation of the Whole Region—A Case Study of Zhemu Town, Guilin City, China

The remediation of inefficient garden land and defective forest land is one of the important sources and types of supplementary cultivated land in the comprehensive land remediation of the whole region. The remediation and development of inefficient garden land and defective forest land will effectively alleviate the multiple pressures faced by cultivated land at present. Taking Zhemu Town, Guilin City, China as an example, on that basis of the data of the third national land survey, using analytic hierarchy process, this paper se-lects six evaluation factors, including water source, traffic, slope, field concentration, farmland infrastructure and villagers’ will, to study the remediation potential of inefficient garden land and defective forest land in Zhemu Town, and delimits four potential divisions, in order to provide the basis for the arrangement of land remediation projects in Zhemu Town. The results show that the northern, central and western regions of Zhemu Town have great remediation potential.


Introduction
Comprehensive land improvement in the whole region can effectively protect How to cite this paper: Liu, M. Y., Cai, X. W., Song, Y. N., Zhao, Y., & Liu, Z. H. (2021). Potential Analysis of Inefficient Garden Land and Residual Forest Land Remediation in Comprehensive Land Remediation of the Whole Region-A Case Study of Zhe-Journal of Geoscience and Environment Protection cultivated land resources, realize centralized contiguous cultivated land, and thus carry out large-scale management of rural cultivated land, accelerate the pace of agricultural modernization, improve rural ecological environment, and promote the development and construction of green villages in China, which plays a vital role in the coordinated development of urban and rural areas in China. The remediation of inefficient garden land and defective forest land is one of the important remediation types in the comprehensive land remediation of the whole region, the research on the remediation potential of inefficient garden land and defective forest land can effectively broaden the ways of supplementing cultivated land, provide strong support for solving the problem of balance between occupation and compensation of cultivated land (Liu, 2020), and have extremely important significance for promoting the scientific development of land resources in China and improving the use value of land resources. At present, there are many researches on the analysis of land remediation potential (Zheng et al., 2018;Yan & Cheng, 2019;Yang et al., 2013;Ding, 2017;Cao & Li, 2016), for example, Li Quanbao (2019) discussed the key problems and suggestions in the development of garden land and defective forest land as new cultivated land sources on the basis of exploring the development practice of garden land and defective forest land (Li, 2019), Jiang Changsheng (2018) explored some methods about the development of remediation potential of garden land and defective forest land, which provided methodological guidance for the analysis of remediation potential of inefficient garden land and defective forest land (Jiang, 2018). Li Quanbao (2016) focused on the problems encountered in the actual development of garden land and defective forest land, while Jiang Changsheng (2018) only studied the technical methods needed for the development of garden land and defective forest land. Neither scholar discussed the problems and methods together. In this paper, analytic hierarchy process is used to analyze the remediation potential of inefficient garden land and defective forest land in Zhemu Town, not only the technical methods but also the remediation potential were studied, it is suggested that the local people's government can make reasonable arrangements for the land remediation project in Zhemu Town with reference to the analysis results and the wishes of the villagers, so as to contribute to improving the income of the villagers in Zhemu Town, promoting the coordinated development of economy, society and ecology in the project area, and realizing the rural revitalization strategy in China.

Location and Natural Environment of the Study Area
Zhemu Town is located in the southern suburb of Guilin, in the northern part of Yanshan District, Zhemu Town has a subtropical climate, heavy rainfall is mainly concentrated in summer, the annual average precipitation is about 1894 mm, the sunshine time is long, the annual average sunshine number is about 1550 hours, the climate is mild, the annual average temperature is about 19˚C, and Zhemu Town faces the river and Lijiang River from northwest to southeast, its tributary Xiangsi River flows through Zhemu Town from southwest, and there is Baizhujing Reservoir in the south, which is rich in water resources. Zhemu Town is a typical karst area, mainly composed of limestone strata. The territory is mainly plain, with a small number of hills distributed in the east. The terrain is low in the east and north, high in the southeast, and the highest point is the top of the middle and east hills, with an altitude of about 400 meters. Details are shown in

Current Situation of Land Use
According to the data of the third national land survey, Zhemu Town has a total

Research Methodology
Analytic Hierarchy Process (AHP) is selected to determine the weight of potential evaluation index of inefficient garden land and defective forest land. Analytic Hierarchy Process (AHP) is a decision-making method that decomposes the elements always related to decision into objectives, criteria, schemes and other levels, and carries out qualitative and quantitative analysis on this basis (Huang et al., 2012;Liu et al., 2013;Peng & Jiang, 2020;Chen & Cao, 2019). Combined with the actual situation of Zhemu Town, we collected relevant data and referred to the existing literature (Lu et al., 2020;Jiang et al., 2012;Deng, 2018;Fan, 2019;Shang, 2020;Ji, 2018;Wang et al., 2017).

Data Processing
The process of data processing is shown in the following flowchart ( Figure 3).  County", finally, selected water source, traffic, slope, field concentration, farmland infrastructure, villagers will of six factors as low-efficiency garden and defective forest land remediation potential evaluation indicators to analyze.

1) Evaluation module
Each evaluation factor is divided into different grades according to the actual situation of Zhemu Town. Following the principle that the higher the grade, the higher the score, each evaluation factor is given the highest grade of 100 points and the lowest grade of 0 points. At the same time, according to the different influence degrees of each evaluation factor on the evaluation of land remediation potential, different weights are given, and the sum of each weight is equal to 1.
The weight of each factor is shown in Table 1 below.

3) Standardized treatment of evaluation indicators
ArcGIS 10.3 software is used to standardize the evaluation index of remediation potential of inefficient garden land and defective forest land. The specific process is shown in Table 2 below.
The score of villagers' wishes is based on widely listening to the needs and wishes of villagers and adopting a unified standardized score of 85 points according to the actual engineering construction. The calculation formula of remediation potential score is as follows:

4) Calculation formula of remediation potential
In which Si refers to the score value of remediation potential, Pi refers to the value of each evaluation index, and Wi refers to the weight of each index relative to the target layer.
Total land remediation potential score S is the sum of remediation potential scores of all evaluation factors, and the calculation formula is as follows: Therefore, the higher the score, the greater the potential of land remediation.

5) Classification of remediation potential
According to the final score, the remediation potential is divided into firstclass potential area, 70 -80 second-class potential area, 60 -70 third-class potential area and less than 60 fourth-class potential area, so as to analyze the remediation potential of inefficient garden land and defective forest land in Zhemu Town.

Potential and Analysis of Inefficient Garden Remediation
Inefficient gardens refer to some gardens with low output due to extensive utilization. It is not only necessary but also urgent to renovate inefficient orchards.
By selecting suitable crops and improving planting methods according to local conditions, the output of orchards can be effectively improved, and it is also conducive to improving the living standards and happiness of local villagers.
Using ArcGis10.3 analysis and calculation, the total area of remediation area of low-efficiency garden in Zhemu Town is 785.62 hectares, of which the first-class potential area covers an area of 394.19 hectares, accounting for 50.17% of the total area of remediation area of low-efficiency garden; The secondary potential area covers an area of 305.65 hectares, accounting for 38.91%; the third-level potential area covers an area of 61.84 hectares, accounting for 7.87%; the fourth-level potential area covers an area of 23.94 hectares, accounting for 3.05%. The remediation potential of low-efficiency garden in Zhemu Town is mainly the first-class potential area and the second-class potential area, while the third-class potential area and the fourth-class potential area are small (see Table 3).

From the potential distribution map of inefficient garden in Zhemu Town
(left in Figure 4), it can be seen that the primary and secondary potential areas of remediation potential in Zhemu Town are concentrated, mainly distributed in the central and western parts of Zhemu Town and the southeast, and sporadically distributed in the northern region; the third and fourth potential areas are mainly distributed in the south of Zhemu Town and a few in the southeast.
The reason for this situation is that the Lijiang River passes through the north of Zhemu Town, the Xiangsi River, a tributary of the Lijiang River, flows through the central and western parts of Zhemu Town from northeast to southwest, and there is Baizhujing Reservoir in the southeast, which makes the water

Potential and Analysis of Remediation of Defective Forest Land
Defective forest land refers to forest land which is destroyed by natural or human intervention, with low coverage rate, low economic value and low ecologi- According to the analysis and calculation of ArcGis10.3, the total area of remediation area of residual forest land in Zhemu Town is 1002.94 hectares, of which the first-class potential area covers 554.27 hectares, accounting for 55.27% of the total area of remediation area of residual forest land; the secondary potential area covers an area of 289.65 hectares, accounting for 28.88%; The third-level potential area covers an area of 54.88 hectares, accounting for 5.47%; the fourthlevel potential area covers an area of 104.14 hectares, accounting for 10.38%. The largest potential area of low-efficiency garden remediation in Zhemu Town is the first-class potential area, followed by the second-class potential area, the fourth-class potential area again, and the third-class potential area is the smallest (see Table 4). The reason for this situation is that the Lijiang River passes through the north of Zhemu Town, Xiangsi River, a tributary of Lijiang River, flows through the central and western parts of Zhemu Town from northeast to southwest, there is Baizhujing Reservoir in the southeast, which makes the water resources in the north, midwest and southeast of Zhemu Town abundant. In addition, in the north, central and western regions of Zhemu Town, the farmland infrastructure is relatively perfect, the traffic accessibility is good, the slope in the central and western regions is relatively low, and the distribution of residual forests in the northern region is relatively concentrated, which makes the first-class potential area in the north of Zhemu Town the widest distribution and the greatest remediation potential, followed by the central and western regions and the southeast region; the southern and central eastern parts of Zhemu Town have a large slope and high terrain, which makes the remediation potential of the defective forest land in the central and eastern parts of Zhemu Town small. In the southeast boundary of Zhemu Town, it is mainly a four-level potential area with small remediation potential due to its far distance from the water source and large

Conclusion
At present, scholars pay more attention to and study the potential of land remediation, but they mainly focus on the potential of agricultural land remediation, which provides a good research method for guiding the development of