Ecological Security Assessment and Territory Spatial Restoration and Management of Inland River Basin—Based on the Perspective of Production–Living–Ecological Space

Abstract

Ecological security evaluation and land space governance are effective ways to ensure regional ecological security and realize sustainable development. This study evaluated the ecological security status at the raster scale and conducted research on the restoration and governance of the national territory, with the aim of implementing accurate restoration, reducing ecological restoration costs, and increasing ecological restoration benefits. Taking the typical arid inland river Shule River Basin as an example, this study selected evaluation factors from production, living, and ecological perspectives, obtained the influencing factors of regional ecological security by spatial principal component analysis, and calculated the ecological security index on the grid scale of production, life and ecological space. The macro-scale national parks, ecological protection red line and other realistic constraints are combined with the grid-scale ecological security evaluation results to achieve accurate land space restoration and governance. The results show that the ecological space accounts for 79.23%, and the production space only accounts for 7.47%, which is similar to other inland river basins in arid areas. The study found that per capita GDP and distance to the road have a significant impact on the ecological security of the study area from the perspectives of production and life, while distance to the water, vegetation coverage, and land cover have a significant impact on ecological security from the ecological perspective. Moderate, moderate low and low ecological security zones account for 72.09% of the total area of the basin, indicating that the ecological security guarantee ability of the Shule River Basin is low. The ecological security level of the living space was the lowest, and the ecological security pattern of the basin area as a whole presented a “higher in the north and south and lower in the middle” characteristic. The land restoration and governance of the Shule River Basin area was divided into five types of ecological control, ecological conservation, ecological enhancement, ecological restoration and ecological management, of which the ecological control area accounted for as much as 35.86%, implying that ecological security in the Shule River Basin has attracted sufficient attention from the government. It is considered that the management of production and living space is more difficult, complex and important, and the proportion of space is relatively small, so it is necessary to focus on the comprehensive management project of ecological protection and restoration. However, the ecological endowment conditions of ecological space in the Shule River Basin are relatively poor, and the distribution area is vast, so natural restoration should be given priority, supplemented by artificial restoration. This study provides a reference for regional ecological security evaluation, ecological civilization construction, and national ecological security research and practice.

1. Introduction

Ecological security is the state of a well-functioning ecosystem and its processes and structure [1], and it is an important component of national security. It is significant in that it is not affected by ecological degradation, and ecosystem services effectively support economic and social development and guarantee human well-being [2]. Since the Industrial Revolution, the severity of environmental degradation and the importance of environmental protection, as well as the ecological security issues that are closely related to humans and their common habitat, have been receiving widespread attention from all walks of life [3,4], especially in arid areas with extremely fragile ecology, desertification, severe soil erosion, and significant disturbance from human activities [5]. Sandstorms frequently occur in the Hexi Corridor of China, which makes national ecological security and regional sustainable and high-quality development face severe challenges [6,7]. Therefore, achieving low-cost restoration, low-cost maintenance, sustainable utilization, and high-quality development in economically underdeveloped inland river basins in arid areas is one of the significant challenges facing human society [8]. Based on the production–living–ecological space perspective, this paper scientifically distinguishes the ecological security level of the regional area at the grid scale and proactively repairs the territorial space with targeted management, which is of great significance for enriching the theoretical and methodological research on regional territorial space repair and management and elevating the fragile ecological environment of arid areas and inland river basins.

Ecological security assessment is a qualitative or quantitative analysis of the degree of ecological security in a certain range [9]. Generally, an index system is constructed through a series of known related indicators to judge and identify the integrity of the regional ecosystem and maintain its health and sustainability under various risks, and provide support for regional government control, urban planning, ecological restoration and governance [10]. The earliest research on ecological security assessment can be traced back to 1941, when Aldo Leopold proposed the concept of land health and used it to evaluate the functional status of land [11]. Ecological security assessment has become a core issue in ecological security, and in recent years, researchers have extensively studied the theory and methodology of ecological security assessment [12,13]. The spatial scale of the research object mainly includes different spatial scales such as global, national, provincial, urban cluster, city, river basin, wetland, industrial and mining areas, natural reserves, and other areas [14,15,16]. Relatively speaking, the inland river basins in arid areas with a fragile ecology and a strong response to global climate change are lacking [17,18]. The research methods used include the comprehensive index method, the analytic hierarchy process, the matter-element model, the TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) method, and the ecological model evaluation method, among others [19,20,21]. The evaluation index system and index synthesis method of ecological security have always been the basis and key content of ecological security research, but there is still no standardized index system and method at present. At present, the common index system for evaluating the use of ecological security is still based on PSR (Pressure–State–Response) or an improved multi-factor comprehensive evaluation model [22,23,24]. However, the research on ecological security evaluation combined with spatial analysis is slightly weak. This method can accurately reflect the spatial distribution and spatial proximity effect of ecological security levels and is conducive to putting forward targeted spatial restoration and governance strategies.

As an important means for achieving the optimization of ecological security patterns, the stability of the ecosystem process, and improvement in ecosystem function, the governance of land restoration plays a crucial role in protecting high-quality ecological space in watersheds and comprehensively repairing damaged ecosystems, thus laying a solid foundation for the ecological security of the national territory [25]. Early research on the governance of land ecological restoration was relatively scattered until 1980, when Cairns introduced it as a small branch of ecology for systematic research, and ecological restoration emerged as a formal research area [26]. Currently, a large amount of relevant research work has been conducted around practical needs in the academic community, but research at the macro level is relatively scarce [27]. Many researchers have carried out related research on different types of damaged ecosystems [28], primarily focused on ecological restoration in mining areas, oil fields, soil, water environments, plants, wetlands, grasslands, and forestry areas [29,30,31,32,33]. Meanwhile, significant research progress has been achieved in theoretical ideas regarding the governance of ecological restoration in national land space [34,35], including the clarification of conceptual connotations, the determination of basic logic, the summary of ideological connotations and implementation approaches, the discussion of transition paths and strategies, the cognitive transformation of time and space integration perspectives, the induction of paradigm for restoration approaches, and the consideration of engineering connotations and innovative countermeasures [36,37]. Overall, existing research focuses mainly on systemic, holistic, and comprehensive understanding [38], while research on ecological restoration for human–land composite ecosystems is still lacking. Therefore, from the perspectives of production, life and ecology, this paper constructs the technical system of land space restoration and management zoning in inland river basins in arid areas in order to improve the comprehensive cognitive level of land space systems and enrich the theory and method of land space protection and restoration and management zoning.

Shule River Basin is one of the important inland river basins in China, which is distributed in the hinterland of the Asia-Europe plate. The ecological function and position of the Shule River Basin are extremely important, and it is an important area to guarantee the national ecological security strategy and jointly build the “the belt and road initiative” [39]. Its natural conditions are relatively harsh, the ecological environment is extremely fragile, the Gobi desert is widely spread and the space suitable for human survival is small, and the oasis only accounts for 5.27% of its total area. Due to the long-term irrational development and utilization of human beings, while the inland river basin in the arid area has made great achievements in economic development, land desertification and salinization are serious, vegetation degradation has reduced biodiversity, the frequency of sandstorms has increased, and the ecological environment of the originally fragile watershed has been increasingly damaged. The ecological security of inland river basins in arid areas has become a major issue that has been attached great importance by the Chinese government and local governments in the northwest inland river basins [40]. Therefore, this paper takes the Shule River Basin as the research area, constructs the ecological security evaluation index system of inland river basins in arid areas from the perspectives of production, life and ecology, evaluates the ecological security of production, life and ecological space in the Shule River Basin, and divides the ecological restoration and management zones of land space in the Shule River Basin, which provides a useful reference for improving the ecological environment quality and ecological protection and restoration of land space in arid areas.

2. Materials and Methods

2.1. Study Area

The Shule River Basin (38°05′–42°45′ N, 92°22′–98°35′ E) is an important inland river basin in arid areas of China, located at the intersection of the Qinghai-Tibet Plateau and the Alashan Plateau in Inner Mongolia (Figure 1). The Shule River originates from the Shule South Mountain of the western section of the Qilian Mountains, with a north-south high-low terrain in the basin, flowing through Subei Mongolian Autonomous County, Dunhuang City, Yumen City and Guazhou County. The upper reaches of the Shule River Basin are characterized by steep mountains, typical of a continental arctic climate, and a large area of permafrost, making it a water source conservation and runoff production area for the entire basin. The middle and lower reaches have a flat terrain, where oases coexist with deserts. Oasis agriculture and water conservancy construction emerged in the middle and lower Shule River in the Han Dynasty, with better irrigation agriculture development in Yumen, Guazhou, and Dunhuang oases. The total area of the basin is 1.15 × 10⁵ km², with an elevation ranging from 913 to 5806 m. The annual average temperature is 7–9 °C, and the annual average precipitation is less than 60 mm, while the evaporation is as high as 1500–3000 mm. The scarce and unevenly distributed precipitation results in a typical continental arid desert climate, with glacier meltwater and mountain precipitation as the main sources of water supply. As of 2020, the basin had a permanent population of 466,700, including 280,700 urban residents and 186,000 rural residents. In recent years, driven by ecological protection policies and influenced by human production and life, the ecological security of the Shule River Basin has been challenged and given opportunities to varying degrees [41].

2.2. Data Sources

This study used 2020 land use data from the “China National Land Use/Cover Remote Sensing Monitoring Database” (CNLUCC) obtained from the Data Center for Resources and Environmental Sciences of the Chinese Academy of Sciences (http://www.resdc.cn accessed on 12 February 2023), with a total accuracy of 88.95% [42], and extracted residential areas, industrial land, water bodies and roads from land use data. Vegetation coverage and the Digital elevation model (DEM) originated from the National Qinghai-Tibet Plateau Scientific Data Center (https://data.tpdc.ac.cn accessed on 15 February 2023), with a spatial resolution of 30 m. The temperature data come from the National Earth System Science Data Center (https://www.geodata.cn accessed on 25 February 2023), with a spatial resolution of 1 km. Population density data come from WorldPop (https://www.worldpop.org accessed on 22 March 2023), with a spatial resolution of 1 km. The spatial distribution data on soil erosion and GDP per capita come from the Data Center for Resources and Environmental Sciences of the Chinese Academy of Sciences (http://www.resdc.cn accessed on 26 March 2023), and the spatial resolution is 1 km. The slope is extracted from DEM data using the slope tool of ArcGIS 10.4.

2.3. Research Methods

2.3.1. Research Ideas

The 18th report of the Communist Party of China proposed the national land management objective of “promoting the intensity and efficiency of production space, creating livable and moderate living space, and achieving ecological space with clear mountains and rivers”, which has received great attention from government departments and academia [43]. Meanwhile, under the main tone of harmonious development between humans and nature, contradictions between humans and the environment in the inland river basin of arid areas are still very prominent [44], and research on ecological security and restoration in these areas is still relatively backward. Based on this, and guided by the theory of the Man–Land relationship areal system, this article divides the national land space from the perspectives of production, life, and ecology and selects 12 ecological security evaluation factors to construct an ecological security evaluation index system in the inland river basin of arid areas. The spatial principal component analysis method is used to obtain the degree of ecological security in each grid within the production, life, and ecological spaces, respectively(Figure 2). Finally, a new technical method for national land space restoration and management zoning is proposed in combination with the current national land space status and ecological security evaluation results. This method can promote regional sustainable development and maximize the effectiveness of regional ecological governance.

2.3.2. Basis for the Division of Production–Living–Ecological Spaces

The division of production, life and ecological space is a comprehensive zoning method for identifying the current spatial structure, pattern and problems. It is important for optimizing the allocation of land resources and the main basis for formulating differentiated national land resource management policies. As the study of “three-dimensional space” is still in the early stage of theoretical exploration, the connotation and spatial scope of “three-dimensional space” are not clear enough or unreasonable, and there are significant differences in the recognition of “three-dimensional space” among different studies [45]. Each type of land use has its dominant function, and one of the manifestations of land use transformation is the transformation of the dominant function of land use, i.e., the conversion between the three dominant functions of production, life and ecology. Based on relevant literature and land use functions such as agricultural production, socio-economic development, and ecosystem services in the Shule River Basin [46,47], this paper divides the Shule River Basin into production space, living space and ecological space (

Table 1. Classification table of production, living and ecological space.

Classification of Land Use in Production, Living and Ecological Space		Basic Data on Land Use Classification	Property Description
Primary Category	Secondary Category
Production spaces	Agricultural production land	Watering fields, orchards, and artificial grasslands	Cultivated land provides direct agricultural products for human consumption
	Industrial and mining production land	Industrial land, mining land, salt fields	Factories and mining sites provide products or services for human beings
Life spaces	Urban residential land	Urban construction land	This includes residential land, as well as public management and service land, that constitute the living space for urban residents.
	Rural living land	Rural resident land use	Human living space outside the urban built-up area.
	Transportation and storage land	Land for pipeline transportation, land for railways, land for highways and land for logistics warehousing	Land used for transportation facilities, transport pipelines, residential roads and corresponding logistics storage facilities for transport purposes.
Ecological spaces	Ecological land for forests and grasslands	Forestry, grasslands and park green spaces	Forests and grasslands play a vital role in preserving soil and water resources and ensuring ecological balance in ecosystems.
	Ecological land for aquatic habitats	Lakes, glaciers, rivers, swamps	Stable areas in aquatic environments, which possess the capacity for self-environmental purification, are important ecological sites.
	Other ecological land	Bare soil, sand soil, and gravel soil	In order to maintain their ecological service function, land such as deserts and unused areas, which are difficult to develop and utilize, should not be opened up.

). Production space is the basic function that uses land as a carrier to ensure human survival and development through social production activities, such as industrial land, orchards, arable land and salt fields. Living space refers to various spatial carrying functions provided during the process of human life and development, such as residential land in urban and rural areas, roads, public service facilities and storage land. Ecological space refers to national land with natural attributes that mainly provide ecological services or ecological products, such as glaciers, wetlands, forests, grasslands and deserts. Because living space and production space have a strong interference effect on ecological space, a 1 km expansion of the production and living space serves as a buffer zone for resisting interference and making the spatial division more in line with the actual situation.

2.3.3. Construction of Ecological Security Evaluation Index System

There are modern glaciers in the Qilian Mountains in the south of the study area, which is an important water conservation and recharge area in the Shule River Basin. Due to the influence of global warming, high-altitude glacial frozen soil and alpine vegetation are more fragile, so the higher the altitude, the lower the ecological security. The degree of steep slope surface unit—the area with a large slope—is more prone to natural disasters such as mudslides and landslides, and the greater the threat to regional ecological security. Vegetation coverage is an important index for measuring surface vegetation status, which is of great significance in evaluating regional ecological security. Generally, the lower the vegetation coverage, the worse the service capacity of the regional ecosystem, which is not conducive to improvement in the regional ecological security level [48]. Land cover type is an important influencing factor for the regional ecological security pattern, with the highest ecosystem service value and ecological security level found in water bodies and forests [49] and the lowest ecological security level found in construction land, which is subject to the greatest human disturbance. Soil erosion is classified according to the external forces of soil erosion, generally including hydraulic erosion, wind erosion and freeze–thaw erosion, which has a very adverse impact on human production and life and surface material vegetation and seriously affects regional ecological security. The higher the degree of erosion, the lower the degree of regional ecological security. Water resources have an important impact on human production and life and regional ecological security. The richer the water resources, the higher the quality of habitats and the safer the regional ecology. Average temperature refers to the annual average temperature in the region. In arid areas, evaporation is often greater than precipitation, and the higher the temperature, the greater the evaporation, which leads to lower vegetation coverage and a lower ecological security level. Per capita GDP and population density often reflect the economic development level and population distribution density of a region. For the inland river basin in arid areas, which is dominated by low-level industries and agriculture, regions with higher per capita GDP and population density often experience more severe damage to the regional ecological environment, resulting in a lower degree of ecological security. Human production and life threaten the ecological security of inland river basins in arid areas and also maintain regional ecological security through ecological environment management. The ecological environment of human production and living space in arid areas is often seriously degraded, so it is urgent to implement comprehensive management of ecological restoration to improve the regional ecological environment [50]. Therefore, the farther away from residential areas, industrial land and roads and other production and living spaces, the higher the degree of ecological security. To sum up, refer to relevant literature and the actual situation of inland river basins [51,52,53,54,55]. A total of 12 indicators were selected from the perspectives of production, living and ecology to construct the ecological security evaluation index system of the Shule River Basin (

Table 2. Table of ecological security assessment factors in Shule River Basin.

Indicator Layer	Evaluation Factors	Level 1 (Height)	Level 2 (Higher)	Level 3 (Moderate)	Level 4 (Lower)	Level 5 (Low)
Production Perspective	GDP per capita	<8000	8000~8500	8500~9000	9000~9500	>9500
	Distance from industrial land/m	>2000	2000~1500	1500~1000	1000~500	<500
Living perspective	Pop density	<300	300~600	600~900	900~1200	>1200
	Distance from the settlement/m	>1500	1500~1000	1000~500	500~100	<100
	Distance from the road/m	>1500	1500~1000	1000~500	500~100	<100
Ecological perspective	Elevation/m	<1600	1600~2400	2400~3200	3200~4000	>4000
	Slope/°	<5	5~10	10~20	20~30	>30
	Vegetation cover	>0.6	0.45~0.6	0.3~0.45	0.15~0.3	<0.15
	Land cover	Waters, woodlands	Grassland	Cultivated land	Unused land	Construction land
	Soil erosion	Microscopic hydraulic erosion; Mild wind erosion; Minimal freeze-thaw erosion	Mild hydraulic erosion; Mild wind erosion; Mild freeze-thaw erosion	Moderate hydraulic erosion; Moderate wind erosion; Moderate freeze-thaw erosion	Intense wind erosion; Extremely strong wind erosion	Severe wind erosion
	Average temperatures	<2	2~4	4~6	6~8	>8
	Distance from water/m	<100	100~500	500~1000	1000~1500	>1500

). Select the per capita GDP from the perspective of production, two evaluation factors from the industrial land distance, and the population density. From the perspective of living, three evaluation factors are selected: population density, distance from residential areas and distance from roads. Seven evaluation factors, such as altitude, vegetation coverage and average temperature, are selected from the ecological perspective.

2.3.4. Spatial Principal Component Analysis

Spatial principal component analysis (SPCA) is a combination of statistical principles and GIS that transforms a number of spatial data that are related to each other to a certain extent into a few almost unrelated comprehensive indicators, and each spatial variable corresponds to a matrix; the influence degree of related spatial variables on the dependent variables is allocated to the corresponding principal component factors. This method can intuitively expand the results of principal component analysis to two-dimensional space. In this paper, according to the relevant literature and the actual situation of the study area, the evaluation factors are divided into 1~5 levels by using ArcGIS software (Figure 3), and then the principal components tool is used to obtain the statistically significant principal components (cumulative contribution rate exceeds 90%) and their corresponding cumulative contribution rates.

2.3.5. Calculation of Ecological Security Index

The principal component space load map with a cumulative contribution rate over 90% is obtained by the principal component analysis method, and the variance contribution rate corresponding to each principal component is weighted. The ecological security index is defined as the weighted sum of multiple principal components. The formula is [56]:

$$ESI={\displaystyle \sum _{j=1}^m{P}_{ij}{w}_j}$$

In the formula, ESI represents the ecological security index of the i-th evaluation unit (grid), P_ij represents the j-th indicator of the i-th unit and w_j represents the weightage of each indicator.

2.3.6. Methodology for Spatial Remediation Governance Zoning

Through the raster-based ecological security assessment, the ecological security level at the regional raster scale is understood, the main factors affecting ecological security are identified, and the key conservation spaces, optimization and upgrading spaces, and key governance and restoration spaces in the region are identified. Based on the ecological security issues, the types of land restoration and management are classified into five categories: ecological conservation areas, upgrading areas, control areas, restoration areas, and governance areas (Figure 4), according to the actual situation of the Sule River Basin from the perspectives of production, life and ecology. This overcomes the constraint of administrative divisions as the partition unit in the past and is conducive to the implementation of targeted ecological restoration projects. The specific partition criteria are as follows: the ecological control areas are determined based on the ecological protection red line, nature reserves and national parks delineated by the natural resources department, and the glaciers and permafrost extracted from land cover data. The ecological protection and restoration of these areas have mandatory government decisions. The ecological high-security zones identified by ecological security assessment have excellent ecological foundations and should be restored naturally as ecological conservation areas to enhance the stability of their ecosystems. The ecological moderate-high-security zones and moderate-security zones are generally distributed around the ecological high-security zones, with relatively poor ecological security, and are classified as ecological upgrading areas to serve as barriers for protecting ecological sources and core areas. The ecological restoration area is composed of moderate-low-security zones and low-security zones, mainly desert and Gobi areas with poor natural ecological foundations. Ecological restoration activities are aimed at excavating ecological potential, windbreak and sand fixation, and controlling ecological degradation. The ecological governance area mainly focuses on the restoration of artificial–natural ecological composite systems in urban and rural construction land and mining land, comprehensive management of inefficient construction land and abandoned mines, and restoration of their ecological functions to achieve coordinated and sustainable development between human social and economic activities and the ecological environment.

3. Results and Analysis

3.1. Distribution Characteristics of Production–Living–Ecological Space

Based on land use data and the production–living–ecological space division proposed in this paper, the layout map of production–living–ecological space in the Shule River Basin (Figure 5) was obtained. The area of production space is 0.86 × 10⁴ km², accounting for only 7.47% of the total area of the Shule River Basin. This is mainly due to the sparse population and underdeveloped socio-economic situation in the Shule River Basin, which results in a smaller proportion of production space. Production space is mainly distributed in the central oasis area, the wild horse river valley in the south, and the surrounding areas of Mazong Mountain in the north. Agricultural production space predominates in the central oasis area and wild horse river valley, while industrial and mining production space predominates in the surrounding area of Mazong Mountain in the north. The area of living space is 1.53 × 10⁴ km², accounting for 13.31% of the total area of the research area. This type of space is mainly composed of point–line–surface network structures formed by residential areas and road traffic. Residential areas are mainly distributed in the central oasis area along the Shule River, while road traffic predominates in the north and south parts of the basin where human habitation is not suitable. Ecological space covers an area of 9.10 × 10⁴ km², accounting for 79.23% of the total area of the research area. Although ecological space accounts for a large proportion, most of it is dominated by the desert and Gobi composite ecosystem, which is relatively fragile. Only the ecological service function of Qilian Mountain National Park in the south is relatively strong.

3.2. Analysis of Factors Affecting Ecological Security

The load matrix and contribution rate of nine principal components can be extracted after spatial dimension reduction analysis of ecological security indicators by using the spatial principal component analysis method. It can be seen from

Table 3. Principal component loading matrix.

Perspective	Evaluation Factors	Principal Component
		1	2	3	4	5	6	7	8	9
Life Perspective	Population density	0.25148	0.48898	0.22198	0.51569	0.18478	0.11578	0.03929	0.09228	−0.39012
	Distance from the settlement/m	0.07968	−0.27712	0.32825	−0.44341	−0.09447	0.40247	0.31223	0.38489	0.34340
	Distance from the road/m	−0.02009	0.09127	0.04790	0.25187	0.40060	0.60152	−0.08344	0.66876	−0.17683
Production Perspective	Elevation/m	0.51268	−0.24542	−0.14742	0.70389	−0.11913	−0.15142	0.55748	0.34689	−0.13002
	Slope/°	0.09452	−0.02334	0.07321	−0.03960	0.45902	0.57006	0.20514	−0.18079	0.60409
Ecological Perspective	Vegetation cover	−0.13145	0.09616	−0.07895	0.37221	0.24367	0.57091	0.10688	−0.45038	0.28055
	Land cover	−0.21958	−0.47863	−0.42311	0.43073	−0.07923	−0.17764	0.59403	0.03984	−0.26024
	Soil erosion	0.55178	0.78636	−0.06228	0.16217	−0.22352	−0.02240	0.03118	−0.05460	−0.13847
	Average temperatures	−0.18998	0.08050	0.82665	0.47009	−0.53367	−0.08309	−0.11632	0.37789	0.50921
	Distance from water/m	−0.14455	−0.00760	−0.23477	−0.14146	0.63321	−0.06536	0.42710	0.00364	−0.16370
	Distance from the settlement/m	0.39838	−0.17572	0.12422	0.51828	0.33188	0.22979	−0.60852	−0.12733	0.09019
	Distance from the road/m	0.87675	0.15717	−0.02759	−0.02462	−0.00042	0.02519	−0.01367	0.02693	−0.04715
	Contribution rate	42.31%	17.45%	13.19%	8.67%	6.03%	4.75%	3.31%	2.82%	1.47%

that the first six principal components, with a cumulative contribution rate of 92.4%, can fully reflect the ecological security information of the Shule River Basin. Through in-depth analysis of the original evaluation index load corresponding to each principal component, it can be concluded that the distance load from the water body in the first principal component is higher (0.87675), which reflects the important influence of water resources on the ecological security of the Shule River Basin and is consistent with the situation of inland river basins in similar arid areas. Vegetation coverage is higher in the second principal component (0.78636), and the sandy land and bare rock account for 78.09% of the total area in the study area. Sparse vegetation coverage leads to obviously low ecosystem service capacity and biodiversity, and vegetation coverage has a significant impact on ecological security in arid areas. Land cover type has a high loading (0.82665) in the third principal component, and it is the result of the combined effects of natural environmental evolution and human activities, closely related to surface vegetation growth, land development, and construction, and significantly affecting regional ecological security. Per capita GDP has a high loading (0.70389) in the fourth principal component, reflecting the significant impact of human socioeconomic activities on ecological security. In the fifth principal component, the soil erosion load is relatively high (0.63321). Because the Shule River is mainly composed of snow and ice melt water from Qilian Mountain, hydraulic erosion and freeze–thaw erosion have a great impact on the ecological security of the basin. Moreover, there are Guazhou and Yumen counties in the Shule River Basin, which are called “world wind banks”, so soil erosion has a profound impact on the ecological security of the basin. The distance from the road has a high load (0.60152) in the sixth principal component. Road construction and the expansion of the road network affect the pattern, structure and function of the ecosystem around the road, and the road blocks the biological migration and activity range, which has an obvious influence on regional ecological security. Overall, the per capita GDP has a greater impact on the ecological security of the study area from the perspective of production, and the distance from the road has a more prominent impact on the regional ecological security from the perspective of life. From the ecological perspective, the distance from the water body, land cover and vegetation coverage have a significant impact on the ecological security of the Shule River Basin.

3.3. Analysis of Ecological Security Evaluation Results

The ecological security index of the Shule River Basin was obtained by weighted summation of the first six principal components whose cumulative contribution rate exceeded 90%. Then, the grade distribution maps of the ecological security degree of production, living and ecological space in the Shule River Basin are extracted, respectively (Figure 6). The areas of high safe and moderate-high safe regions in the production space were 0.13 × 10⁴ km² and 0.11 × 10⁴ km², respectively, accounting for 14.71% and 13.03% of the total area and mainly distributed in the river valley zone of the Qilian Mountains in the southern part of the basin. The area of production space in the region with a moderate or lower ecological security level was 6194.86 km², accounting for 72.26% of the total area, and was mainly distributed in the oasis regions within the basin and sparsely distributed in the north. The areas of high and moderate-high safe regions in living space were 0.17 × 10⁴ km² and 0.21 × 10⁴ km², respectively, accounting for 11.34% and 13.65% of the living space and mainly distributed in the river valley zone of the Qilian Mountains, with a small amount distributed in the oasis area. The area of moderate, moderate-low and low ecological security zones in living space is 1.15 × 10⁴ km², accounting for 75.01% of living space, indicating that the ecological security degree of living space is obviously low and mainly distributed in human settlements within the oasis areas and along major transportation routes, which had a significant relationship with ecological security issues caused by human production activities. The areas of high and moderate-high safe regions in ecological space were 1.40 × 10⁴ km² and 1.12 × 10⁴ km², respectively, accounting for 15.48% and 12.38% of the ecological space, and mainly distributed in the southern part of the Qilian Mountains, indicating that the ecological security level in ecological space was significantly higher than that in production and living spaces. The area of moderate, moderate-low and low ecological security zones in the ecological space was 6.51 × 10⁴ km², accounting for 72.14% of the total area. The Gobi desert ecosystem is dominant, mainly distributed in the marginal areas of Kumtag Desert and Badain Jaran Desert, and the ecosystem service capacity and ecological security degree are obviously lower than in other regions. Overall, the distribution of ecological security in the Shenmu River Basin was extremely uneven, with the northern region being a typical extremely arid desert natural ecosystem with relatively scarce animal and plant resources and fewer human activities, mainly focused on mining industries and primarily showing a moderate ecological security level. The central region includes oases formed by the irrigation of the Shenmu River, such as Guazhou, Yumen, and Dunhuang. This region is the main area for human agricultural production and urban construction activities, and the extreme scarcity of water resources due to being surrounded by deserts has led to the lowest regional ecological security level. The southern region has the highest degree of ecological security, mainly because this region is Qilian Mountain National Park and there are many nature reserves, and wetlands, forests and grasslands with high habitat quality are densely distributed, which greatly improves the ecological resistance and resilience stability of this region.

3.4. Restoration and Governance of National Territory Space

3.4.1. Zoning for the Restoration and Governance of National Territory Space

According to the research technical methods proposed in this article for land spatial restoration and governance zoning, four types of patches, including ecological protection red lines, glaciers and permafrost, national parks and nature reserves, are merged into an ecological control area using the Union tool in ArcGIS. Urban and rural construction land and industrial and mining land patches are merged as an ecological management area. Based on the ecological security evaluation level map, the ecological control area and ecological remediation area are erased using the Erase tool in ArcGIS. The remaining ecological security level map is then divided into ecological conservation areas, upgrading areas, and restoration areas according to the research technical methods for ecological restoration zoning. Finally, using the Union tool, the five types of ecological restoration zones are merged to obtain the Shule River Basin’s ecological restoration zoning map (Figure 7). The research results are essentially consistent with the actual demands for ecological restoration in the research area. The ecological control area covers a total area of 4.14 × 10⁴ km², accounting for 35.86% of the total research area. As the Qilian Mountain National Park, Yanchi Bay, Dunhuang West Lake, Mazongshan North Goat, Anxi Extreme Arid Desert and 16 other national and provincial natural reserves are distributed in the Shule River Basin, most regions in the basin fall under the category of natural reserves. Thus, ecological protection and management are greatly subjected to policy intervention. The ecological conservation area covers a total area of 1.04 × 10⁴ km², accounting for 8.96% of the total area. This region mainly consists of forest, grassland and wetland ecosystems, mainly distributed in the northern part of the Qilian Mountain area, the Mazongshan region and the periphery of the oasis. This area plays an important role in water conservation, soil protection and ecological safety of the oasis. The ecological enhancement area covers an area of 2.72 × 10⁴ km², accounting for 23.51% of the Shule River Basin. It is mainly distributed in the periphery of the ecological control area and the ecological conservation area, which is the ecological barrier of the ecological core area of the Shule River Basin. The ecological restoration area covers a total area of 3.63 × 10⁴ km², accounting for 31.42% of the total area. This area is mainly composed of desert and Gobi desert ecosystems, with a sensitive and fragile ecological environment. It is an important area for curbing ecological degradation and repairing and maintaining damaged ecosystems. The ecological management area covers a total area of 279 km², which is relatively distributed in the oasis area. The main contents should be agricultural land consolidation, construction land consolidation and rural ecological protection and restoration, and the land management mode of protecting cultivated land, intensively saving land and improving the ecological environment should be the core goal.

3.4.2. Strategy for the Restoration and Management of the National Spatial Environment

During the ecosystem restoration process, water resource spatial allocation has a significant impact. Due to the abundance of water resources, the difficulty of ecosystem restoration from south to north in the research area is increasing. From the perspective of topographical factors, as the altitude increases, ecological stress factors continue to increase due to changes in temperature, frost-free periods, and wind speed [57], and the ecological stress factors are increasing, which makes the Qilian Mountain area in the south of the Shule River Basin a typical ecologically fragile and sensitive area. We should build a long-term mechanism for ecological environment supervision, position the ecological function with water conservation and biodiversity protection as the core, and build a strong ecological security barrier in the western part of the country. The central oasis area has significant advantages in water resources, climate, topography, etc. and is the area with the least difficulty in ecological restoration. However, other areas outside the central oasis area have greater difficulty in ecological restoration due to the problem of water scarcity, especially the eastern and western regions adjacent to the desert. Therefore, considering the abundance of water resources, changes in biodiversity, climate change, and ecological restoration costs, different types and intensities of artificial support and guidance measures need to be implemented.

According to the research results, the ecological control area needs to ensure that important natural ecosystems, natural relics, first-class water sources and biodiversity are systematically protected, and urban and rural construction and industrial layouts are prohibited. Most of the ecological control areas belong to the Qilian Mountains National Park and various nature reserves and should be the focus of ecological protection and restoration through afforestation, mountain closure and afforestation, and grass rehabilitation to improve water source conservation and ecological product supply capacity. Ecological conservation areas are the ecological core areas of the Shule River Basin and are extremely important for regional ecological security and stability. Ecological space-layering control should be adopted, and construction and development should be prohibited within the conservation area and within 5 km around it. Ecological migration and mountain closure protection should be implemented to reduce human interference with the ecological environment. Ecological upgrading areas are the outer barriers of ecological control and conservation areas and are also the green barriers to prevent the desert from encroaching on the oasis border area. It is necessary to strengthen the control of desertification around it, control wind and sand erosion, and improve wind and sand fixation capacity through the construction of shelter forests, green corridors and special treatment of key wind and sand outlets. The ecological restoration area is mainly the wind and sand desert area, and the difficulty of ecological restoration is relatively high. Limited water resources should be used moderately for afforestation and desert control. Measures such as sand barrier compression and sand control should be taken around important ecological function areas. The ecological restoration project of desertified grassland should be emphasized, and grazing and desertified land closure projects should be implemented. At the same time, relevant research shows that the solar industry in deserts and Gobi has significant ecological functions in preventing and controlling desertification [58], and regional advantages should be given full play to actively develop the solar industry in the ecological restoration area to improve its ecological and economic benefits. The ecological management area is dominated by human production and living space and should focus on the renovation of inefficient construction land and actively improve the ecological function and human settlement quality in the production and living space. Rural living space should promote scattered and decentralized homesteads and, based on the standard of 150 m² per capita residential land, 40.34 km² of residential land can be organized in the Shule River Basin to build new rural communities, so as to increase rural production and ecological space and effectively promote rural revitalization.

4. Discussion

4.1. Analysis of Factors of Ecological Security in Inland River Basins in Arid Areas

Based on the perspective of “production-living-ecological”, various factors were selected to evaluate the ecological security degree of the Shule River Basin, and the main influencing factors and mechanisms were obtained. At the same time, compared with other research methods, the spatial principal component analysis (SPCA) can objectively obtain the factor weights and accurately express the results of ecological security assessment and the needs of land spatial restoration and management on the grid scale, which has the characteristics of practicality, economy and universality for desertification control and oasis protection in the economically underdeveloped inland river basin in northwest China. The results show that the main factors affecting the ecological security of the Shule River Basin are reflected in production, life and ecology, which further shows that both man and nature have a profound impact on the ecological security of inland river basins in arid areas. At the same time, previous studies show that the richness of water resources is the first influencing factor of ecological security in arid areas [59], which is consistent with the research results of similar areas in arid areas and this paper. Land cover types in inland river basins in arid areas are often largely limited by water resources, which makes the regional ecological security pattern closely related to the distribution of water resources. At the same time, human production and life are also important factors affecting the ecological security of inland river basins, which is consistent with other research results [60,61]. The unhealthy level of ecological security in the Shule River Basin needs to be protected, rehabilitated and managed urgently, the relationship between human production and life and the rehabilitation and management of national space should be clarified, the policy of “determining city by water, land by water, people by water and production by water” should be implemented, and the carrying capacity accounting and unified management of river basin water resources should be implemented, so as to meet the production and domestic water demand, avoid land degradation and other threats to regional ecological security caused by over-exploitation of water resources, and realize stable and sustainable utilization of water resources.

4.2. Governance and Protection of Urban and Rural Living Space Systems in Arid Areas

The acceleration of urbanization and the increase in urban populations have intensified the demand for urban residential land, resulting in the continuous conversion of other land types surrounding the cities to urban residential land, providing spatial security for urban construction and promoting the expansion of urban residential land. However, the old urban areas often have poor living experiences, concentrated and tense resources, compressed public space, and overloaded infrastructure [62]. Therefore, under the background of the ecological protection red line, permanent basic farmland, and the delineation of urban development boundaries, the development concept for urban living space should adhere to the high-quality development concept of connotation-based, intensive, and green, increase the construction of basic infrastructure such as water supply and drainage, sewage and waste disposal, accelerate the transformation of shantytowns and urban villages, improve public service facilities such as science, education, culture, and health, strengthen environmental remediation and park and green space construction, inherit historical context, and build wonderful towns. Although the population of rural residents in the watershed is only 186,000, the residential land area is as high as 68.24 km², far exceeding the national standards for per capita rural residential land use, mainly due to past irregular approvals and the phenomenon of “building new while not tearing down the old”, resulting in low efficiency of rural residential land use. Although precise poverty alleviation, relocation, rural construction land consolidation and reclamation, and comprehensive land consolidation measures have been implemented [63], the effects are still not significant. In the future, efforts should be made to increase the implementation of ecological migration to reduce the fragmentation of rural residential areas, deeply implement rural greening and beautification actions, strengthen rural-style guidance, and promote harmony between the village form, natural environment, and traditional culture.

4.3. Coordinated Development of Production, Living, and Ecological Space in Oases in Arid Areas

The interaction between material circulation and energy flow in oases in arid areas endows the system with self-sustaining and regulating abilities [64], but the stability mechanism of the system is limited. When the interference of population and economic development exceeds the adjustable or bearable capacity of the system, the balance of the system will be disrupted. In the context of arid climate and water allocation policies, water resources, as the key link among production, living and ecology in oases, have a fixed quantity and must be utilized within the resilience range of the system. However, the continuous expansion of cultivated land and living space has caused widespread over-extraction of groundwater, resulting in vegetation degradation, land desertification and food and ecological insecurity [65], which restrict the virtuous cycle of the ecosystem and the sustainable and high-quality development of the economy and society. For oases in arid areas, with water resources as a constraint, scientific assessment of the appropriate population and cultivated land scale, precise estimation of the optimal area ratio of production, living, and ecological space, and attention to the coordinated development of social economy and ecological protection should become the focus of decision-making and scientific research in the future. Efforts should be strengthened to comprehensively improve the production and living space in oases, promote the remediation of agricultural land and low-efficiency construction land, and reclaim historical damaged land to transform it from dispersed and fragmented to centralized and connected. At the same time, increasing investment in science and technology, changing production and living methods to increase economic and ecological benefits, and improving the utilization efficiency of living and production space can achieve rational spatial allocation and transformation.

4.4. Ecological Spatial System Management in Arid Inland River Basins

Ecological spatial system management in arid inland river basins is a strategic goal that is global and long-term. Enhancing the continuity of the overall ecological spatial pattern is an important aspect of regional ecological system management [66]. Currently, the ecological landscape of the lower and middle reaches of the Shule River Basin is fragmented by unused land, obstructing the ecological flow of the landscape. This not only greatly threatens the biodiversity of the landscape but also causes incalculable damage to the regional environment due to the ecological imbalance of the landscape as a whole. Therefore, in conjunction with the protection of the basic ecological control line, it is necessary to maintain and construct large-scale ecological system service patches, strengthen the connection between isolated patches, and form ecological corridors between ecological nodes to enhance the integrity and continuity of the regional ecological space. At the same time, for the mountain–oasis–desert complex ecological system in arid inland river basins, water resources are the foundation of ecological development. Therefore, the comprehensive management of the inland river basin system in arid areas should be determined by water and proceed according to water allocation. In satisfying the oasis’ water resource needs, water resources should be reasonably allocated for the restoration of desert and Gobi ecological systems. Due to the relatively poor ecological endowment conditions in arid inland river basins, there is a great demand for ecological restoration and management engineering, which should primarily rely on natural recovery and secondarily on artificial restoration. Meanwhile, ecological economic development should be reasonably developed to increase income and support ecology, safeguard ecological security boundaries, and prevent the encroachment of the Kum Tagh and Badan Jilin deserts on the central oasis area. Advantageous ecological resources in the Qilian and Mazong Mountains should also be rationally utilized for ecological tourism development, and land and grassland that are not suitable for use should be restored to improve the ecosystem service capacity and stability.

5. Conclusions

Based on the perspective of “production-living-ecological”, 12 evaluation factors were selected to construct the ecological security evaluation system of the Shule River Basin, the main factors affecting ecological security were obtained by spatial principal component analysis, and the ecological security evaluation results for the Shule River Basin were obtained. On the basis of the evaluation, the technical method of regional land space restoration and governance can promote regional sustainable development and maximize the effectiveness of watershed ecological governance. The results show that the ecological space of the Shule River Basin accounts for 79.23%, but the desert ecological system with poor ecosystem service capacity is the main type. Production space only accounts for 7.47%. Through analysis of the influencing factors of regional ecological security, it is found that the per capita GDP has a significant impact on the ecological security of the study area from the perspective of production, and the distance from the road has a significant impact on the regional ecological security from the perspective of life. From the ecological perspective, the distance from the water body, vegetation coverage and land cover are the main influencing factors of the ecological security of the Shule River Basin. The moderate, moderate-low and low ecological security zones in the Shule River Basin account for 72.09% of the total area, indicating that the overall level of ecological security in the research area is low. Among these, the ecological security level of life space is the lowest, and areas with ecological security levels below moderate accounted for 75.01% of the total area of living space. From the perspective of the spatial distribution of ecological security levels, the research area as a whole presents a “higher in the north and south and lower in the middle” pattern, and it is recommended to enhance the ecological quality of oases in the middle and build ecological barriers around oases in the middle for ecological construction layout. At the same time, the real constraints of macro-scale ecological protection red lines, natural protected areas, national parks, and other real constraints and grid-scale ecological security evaluation results were combined using the ArcGIS tool. Five types of land spatial restoration and management zoning were identified, including ecological control, ecological preservation, ecological improvement, ecological restoration, and ecological management, with respective areas of 4.14 × 10⁴ km², 1.04 × 10⁴ km², 2.72 × 10⁴ km², 3.63 × 10⁴ km² and 279 km². The proportion of ecological control areas is as high as 35.86%, which indicates that the ecological security of the Shule River Basin has received enough attention from government departments. According to the research results, it is suggested that ecological improvement should take priority in production and life space. The complexity, difficulty and importance of ecological restoration in production and life space are higher, and major ecological protection and restoration projects should be vigorously implemented. While the ecological endowment conditions of the Shule River Basin are relatively poor, natural restoration should be the priority, with artificial restoration as a supplement. The land spatial restoration and management strategy proposed in this paper for the Shule River Basin aims to provide a useful reference for improving the regional ecological environment quality and optimizing the national land spatial pattern.