Eco–Environmental Effects of “Production–Living–Ecological” Space Land Use Changes and Recommendations for Ecological Restoration: A Case Study of the Weibei Dryland in Shaanxi Province

Abstract

As eco–environmental effects have become important considerations in the construction and planning of production, living, and ecological spaces, we used a combination of quantitative and qualitative methods to analyze the eco–environmental effects’ spatiotemporal evolution and present appropriate ideas for ecological restoration based on the land use data. The results show that during the research period both an improvement and degradation of the regional eco–environment occurred simultaneously. In the earlier period, the ecological environment tended to be worse, while in the later period, the eco–environmental quality was dramatically enhanced. Pasture ecological land in the study area had the strongest positive impact on the eco–environmental quality, while the negative effect of agricultural production land was severe. The quality of the regional eco−environment was enhanced (degraded) due to the extension (contraction) of ecological land. The construction of an ecological environment is a complex engineering task. Although the eco−environment in most areas of the study area showed an improving trend, the overall eco–environment remains relatively fragile. In the course of supporting high–quality regional social and economic growth and pursuing high–level environmental preservation strategies, we should take corresponding measures to protect and repair the regional ecological environment.

1. Introduction

The spatiotemporal evolution of land use patterns in terms of form and function is referred to as land use change, and it is frequently congruent with regional socioeconomic growth [1,2,3]. Changes in land use functions are primarily reflected in quantity (i.e., the area of land occupied by specific land use types) and the geographical redistribution of land resources among regions designated for agricultural production, human habitation, and ecological services. Therefore, land use variability can indicate the extent of regional socioeconomic transformation over time [4]. The scope and intensity of land resource development and usage have grown as social productive forces, regional industrialization, and urbanization have progressed. However, the developmental progression of land and resources in China is increasingly disrupted due to the profound influence of conventional development philosophy that prioritizes “placing more emphasis on production, less on living, more on construction, and less on ecological” uses. Thus, the regional production, living (i.e., habitation), and ecological space (PLES) land use structure has tended to be unbalanced, and the quality of human settlements has subsequently decreased [5,6,7]. Therefore, issues such as the deterioration of ecosystem services and the glaring incompatibility between human activities and the land worsened. Currently, both domestic and international researchers have engaged in a variety of investigations focused on land use change and have produced successful findings regarding the spatiotemporal pattern of land use variability [8,9], the driving mechanisms behind these changes [10,11], the dynamic monitoring of land change [12], and the ecological environmental response to these change patterns [13,14,15]. After the 18th CPC National Congress clarified the PLES planning goals, the 19th CPC National Congress reiterated the importance to “pursue a civilized development path that ensures increased levels of production, better living standards, and a sound ecology” [16,17]. In light of this, the land use system based on PLES, which connects land use change with local socioeconomic transformation and development, has emerged as a key entry point for ecology, geography, and economics, as well as other disciplines in terms of conducting research on land use change [18]. Research on PLES–related land use transformation now focuses mostly on theoretical frameworks, the delineation of principles, the evolution of patterns, the transformation of land functions, and other related topics [19,20,21,22]. However, several studies have examined the connection between land use change and eco–environmental consequences, but most of those studies have limitations, such as short observational periods, narrow scopes, or a lack of recommendations to optimize land use. Therefore, there is space for improvement.

The Weibei dryland, which is part of the “Loess Plateau–Sichuan–Yunnan Ecological Barrier” under the national “Two Screens and Three Belts” ecological security policy, is situated in central Shaanxi Province. Additionally, the region is the primary location for the execution of “China’s Western Development Strategy” and “The Belt and Road Initiative”. Moreover, as an important base for the production of fruits in China and an important agricultural production zone in Shaanxi Province, the local ecological environment is extremely sensitive and fragile, and the Weibei dryland has been severely impacted by natural disasters (such as droughts, sandstorms, and frosts) for a long time. Additionally, land in the region has become increasingly developed and occupied, which has become a severe issue related to people’s intense desire for economic progress. Therefore, the types of regional land usage vary dramatically. As a result, studies in the Weibei dryland have practical significance in terms of balancing the growth of the ecological environment, socioeconomic development, and resource extraction and usage. Ultimately, these efforts may realize the complete and coordinated development of regional PLES. Based on this, we quantitatively examined the spatiotemporal variability of land use alteration with different functions and their effects on the environment from the perspective of the PLES principle over different periods from 1980 to 2020. Accordingly, we proposed pertinent ecological restoration policies with a view to providing some guidance for the land resources development and, thus, creating a safe ecological pattern.

2. Materials and Methods

2.1. Study Area

The Weibei dryland refers to the Loess Plateau area located in the southern part of the northern Shaanxi hilly and gully region and the northern part of the Guanzhong Plain, which includes 50 counties (cities) under the jurisdiction of Baoji, Xianyang, Weinan, Yan’ an, and Tongchuan, with longitude and latitude ranges of 106°18′–110°38′ E and 33°35′–37°31′ N, respectively, and a total area of approximately 8.24 km × 104 km (Figure 1). There are four distinct seasons in most of the region’s warm continental monsoon climate. Warm and wet periods occur simultaneously. Precipitation is primarily concentrated in the summer and fall, with an average annual precipitation of approximately 600 mm. The study area has emerged as a key region for the growth of agriculture, animal husbandry, and the fruit industry. Additionally, Shaanxi Province is known for the enrichment of natural resources due to the fact of its unique natural geographical conditions. Due to the increased industrialization and urbanization in recent years, mineral and land resources in the study region have been continually extracted and consumed, which has resulted in a major shift in the land use structure. Therefore, studying the PLES ecological environmental response to land use changes in the Weibei dryland will contribute to a more equitable PLES allocation while also supporting the comprehensive, coordinated, and sustainable growth of the regional society, economy, and ecology. Furthermore, this study has implications for other resource–rich regions of China in the development, utilization, management, and control of their land resources.

2.2. Data Preparation

The data (including 1980, 2000, and 2020) used in this study were obtained from the Chinese Academy of Sciences (CAS), and the platform was Resource and Environment Science and Data Centre (http://www.resdc.cn/, accessed on 10 September 2021). These data were derived using Landsat TM/ETM+/OLI remote sensing images, which served as the major source of information, and artificial visual interpretation. After the field test and error correction, the overall accuracy of 6 categories (forestland, grassland, construction land, cultivated land, water area, and unused land) was higher than 94.3%, and the accuracy of the 25 subcategories exceeded 91.2% [23,24,25]. To further evaluate the accuracy of the image data, we utilized the confusion matrix function within ENVI to assess the correctness of the image. According to the calculation, the producer accuracies of the productive land use data in 1980, 2000, and 2020 were 81.78%, 98.36%, and 90.61%, respectively, with corresponding user accuracies of 89.66%, 98.59%, and 82.45%, respectively. Similarly, the producer accuracies of the ecological land use data in these three periods were 93.67%, 99.59%, and 89.77%, with corresponding user accuracies of 89.83%, 98.84%, and 94.32%, respectively. In addition, the producer/user accuracies of the living land in different periods were all above 70%, so it can be judged that the accuracy of the categorization of the selected land use data complied with the demands of the study.

We referred to the GB/T21010–2017 “Classification of Land Use Status” standard and the classification principles from previous research findings from the standpoint of natural features of land use [26,27,28]. Then, depending on the land use type’s principal purpose and its numerous subcategories needed to satisfy the demands of human development, we converted the original data into a land use classification system with the PLES as the dominant function, which typically contained 3 categories and 8 subcategories. Finally, according to the assigned prerequisites [7,29,30,31] for the ecological environmental quality of various land types, we employed the area weighting approach to assign the ecological environmental quality to the subcategories in the Weibei dryland (

Table 1. Land use function categorization of the PLES and eco–environmental quality index (EQI).

Land Use Function Categorization		Subcategories of Original Land Use System	EQI
Category	Subcategory
Productive land	APL	Paddy field, dry land	0.261
	IML	Other construction land	0.166
Living land	ULL	Urban land	0.200
	RLL	Rural residential area	0.200
Ecological land	FEL	Open woodland, woodland, shrubland, other woodland	0.694
	PEL	High–, medium–, and low–coverage grassland	0.458
	WEL	Canal, lake, reservoir pond, permanent glacier snow, coast, shoaly land	0.579
	OEL	Sandy ground, Gobi, marsh land, saline land, bare land, gravelly land	0.015

APL: agricultural production land; IML: industrial and mining land; ULL: urban living land; RLL: rural living land; FEL: forest ecological land; PEL: pasture ecological land; WEL: water ecological land; OEL: other ecological land; the same for below [23,24,25].

).

2.3. Methodology

2.3.1. Eco–Environmental Quality Index (EQI)

The EQI can quantitatively characterize the ecological environmental quality over time by constructing a relationship between the difference in the ecological environmental quality and the change in the structural proportion of the PLE. The expression [7] is as follows:

$$EI={\displaystyle \sum }_{i=1}^n\frac{A_{ki}}{A_k}{E}_i$$

(1)

where EI is the EQI of the region; A_ki is the area of land use type i; A_k is the total area; E_i is the EQI of land use type i; and n is the number of land use types.

2.3.2. Land Use Transfer Matrix Model

The land use transfer matrix model can describe the transfer status (amount and direction) of land use types across time in a comprehensive and intuitive manner, and it can be used for quantitative research on the structural features and functional types of land use. The mathematical formula [18] is as follows:

$$S_{ij}=\left\{\begin{array}{cccc}{S}_{11}& S_{12}& \dots & S_{1n}\\ S_{21}& S_{22}& \dots & S_{2n}\\ \dots & \dots & \dots & \dots \\ S_{n1}& S_{n2}& \dots & S_{nn}\end{array}\right.$$

(2)

where S_ij is the area converted from land use type i to land use type j at the end of the study period (km²); Snn is the area of land use type (km²); and n is the number of land use types.

2.3.3. Ecological Contribution Rate of Land Use Transformation

The ecological contribution rate of land use transformation can characterize the changes in the regional ecological quality resulting from the transformation of particular land use categories. The algorithm [28] is as follows:

LEI = (LE_t+1 − LE_t) EA/FA

(3)

where LEI is the ecological contribution rate of the land use transformation; LE_t and LE_t+1 are the indicators of the eco–environmental quality in the initial and final stages of a certain changed land use categories, respectively; and EA and FA are the changed area and total area of the land use categories in the study area, respectively.

3. Results

3.1. The Evolutionary Characteristics of PLES Land Use Functions

3.1.1. The Temporal and Spatial Variation in PLES Land Use

We selected the 1980, 2000, and 2020 land use remote sensing data of the study area and chose 2000 as the boundary to investigate the spatial variation and structural features of the PLES land use framework in the Weibei dryland in different periods (Figure 2,

Table 2. Area of and variation in the PLES land use in the Weibei dryland from 1980 to 2020.

Category	Area/km2			Subcategory	Area/km2
	1980	2000	2020		1980	2000	2020
Productive land	32,600.79	32,676.01	29,733.94	APL	32,557.31	32,616.63	29,389.70
				IML	46.97	62.90	347.37
Living land	1434.74	1712.44	2291.91	ULL	149.61	243.26	519.21
				RLL	1258.27	1469.33	1772.88
Ecological land	46,845.94	46,492.72	48,846.48	FEL	19,024.68	19,102.86	20,074.52
				PEL	27,093.46	26,734.47	28,060.13
				WEL	585.88	551.22	562.67
				OEL	146.96	109.17	154.48
Category	Variation Area/km2			Subcategories	Variation Area/km2
	1980–2000	2000–2020	1980–2020		1980–2000	2000–2020	1980–2020
Productive land	75.22	−2942.07	−2866.85	APL	59.33	−3226.94	−3167.61
				IML	15.93	284.47	300.40
Living land	277.70	579.47	857.17	ULL	93.65	275.94	369.60
				RLL	184.06	303.55	487.61
Ecological land	−353.22	2353.76	2000.54	FEL	78.18	971.66	1049.84
				PEL	−358.99	1325.66	966.67
				WEL	−34.67	11.45	−23.22
				OEL	−37.79	45.31	7.52

Source: authors’ own construction.

) by applying the PLES land use function classification system (Table 1). In general, ecological land occupied the largest area in the Weibei dryland, followed by production land, and living land occupied the smallest area. In terms of the spatial distribution, the ecological land was mostly spread across the northern Shaanxi Plateau and Qinling Mountains, while the production land and living land were primarily focused on the Guanzhong Plain. Considering the change over time, the ecological land showed that it had initially decreased in area before expanding. Its expansion was quite evident overall and showed a total expansion of 2000.54 km² over the previous 40 years. In contrast, the area occupied by production first increased and then declined, and the degree of decline was substantially larger than the degree of increase. During the study period, the production land area decreased by approximately 2866.85 km². In contrast, the area occupied by living land demonstrated a steadily increasing trend and grew by 857.17 km² over the previous 40 years. Comparatively, it was discovered that in the Weibei dryland, the growth of production and living land over the first 20 years was comparable to the reduction in ecological land. This result indicates that in the early stages of reform and opening up, due to the impact of the national policy of rapidly growing the social economy, the change in the PLES land use structure within the research region primarily involved the ongoing growth of production and living land, as well as the extensive occupancy of ecological land. Conversely, the expansion of living and ecological land was equivalent to the area of the reduction in production land over the last 20 years. This result demonstrates that with the advancement of the Western Development Strategy and the promotion of the concept of ecologically oriented civilization, the structural change in PLES land use in the Weibei dryland showed a trend of increasing living land and the gradual recovery of ecological land since the 21st century. This change was primarily caused by the occupation of production land by ecological land and living land.

In the Weibei dryland, the agricultural production, pasture, and forest ecological lands covered the widest area, according to the geographical distribution of the land use subcategories. Agricultural production land was predominantly concentrated in the Guanzhong Plain. However, the spatial pattern of the pasture ecological land was exactly the opposite, with the exception of the Guanzhong Plain, where it was dispersed across the research region. The forest ecological land was mainly located in the Ziwu Mountains and Huanglong Mountains in the western and eastern parts of the Northern Shaanxi Plateau, respectively, and the Qinling Mountains in the southern part of the Guanzhong Plain. Limited by the level of regional social development and natural circumstances, the scale of the industrial and mining production land and urban living land, as well as water ecological land, was small. In terms of structural change, the ecological land decreased overall from 1980 to 2000, except for forest ecological land, which expanded by 78.18 km². It is notable that the pasture land declined by 358.99 km², which was the largest decline among the subcategories. On the other hand, the production land and living land both showed varied degrees of expansion. During this period, the rural and urban living lands increased by 184.06 km² and 93.65 km², respectively, whereas the agricultural and industrial and mining lands increased by 59.33 km² and 15.93 km², respectively. Nevertheless, agricultural land declined by 3226.94 km² between 2000 and 2020. The other functional land types showed different degrees of expansion. In particular, pasture and forest ecological lands experienced the greatest expansion, with increases of 1325.66 km² and 971.66 km², respectively. To summarize, from 1980 to 2000, the production and living lands in the Weibei dryland increased the most, while the area of ecological land shrank. In contrast, between 2000 and 2020, living and ecological lands grew dramatically, while the area occupied by production land declined significantly.

3.1.2. The Transformation Mode of PLES Land Use

By constructing a transfer matrix for the subcategories in the PLES (

Table 3. Transfer matrix of the PLES land use in the Weibei dryland during 1980–2000 (unit: km²).

1980	2000
	APL	IML	ULL	RLL	FEL	PEL	WEL	OEL
APL	32,026.62	8.88	55.07	160.27	97.03	40.64	50.62	2.15
IML	0.00	34.93	0.00	0.00	0.00	0.00	0.00	0.00
ULL	0.00	2.70	89.78	0.00	0.00	0.00	0.00	0.00
RLL	0.00	0.00	0.13	1121.91	0.00	2.71	0.00	0.00
FEL	26.05	0.42	1.93	0.90	18,792.58	124.63	1.82	0.50
PEL	410.22	0.05	2.59	1.29	97.03	26,898.39	39.14	1.56
WEL	91.16	0.00	0.12	0.64	5.71	27.09	487.69	0.48
OEL	3.26	0.00	0.00	0.13	32.34	0.00	6.68	142.29

Source: authors’ own construction.

and

Table 4. Transfer matrix of the PLES land use in the Weibei dryland during 2000–2020 (unit: km²).

2000	2020
	APL	IML	ULL	RLL	FEL	PEL	WEL	OEL
APL	29,576.76	43.17	106.94	440.65	1104.15	3510.24	102.64	11.90
IML	3.26	9.27	1.17	0.29	0.00	0.00	0.28	2.64
ULL	6.52	0.14	108.62	0.88	0.00	2.67	0.39	0.00
RLL	241.36	0.87	12.46	991.65	5.73	16.04	1.05	0.05
FEL	466.42	2.02	3.58	9.99	16,995.81	719.16	10.09	16.24
PEL	2211.41	7.14	9.58	22.48	981.89	22,440.92	41.62	17.12
WEL	97.85	0.27	0.90	3.09	7.64	34.75	393.68	4.63
OEL	9.78	0.03	0.00	0.00	5.73	10.69	1.49	56.58

Source: authors’ own construction.

), we could further explore the transformation characteristics of land use function in the Weibei dryland in 1980 and 2020. It was shown that all types of ecological land in the study area were reduced from 1980 to 2000 and were mostly converted to agricultural land. Therefore, the pasture ecological land type decreased the most, followed by the water and forest ecological land subcategories. Over the past 20 years, 410.22 km², 91.16 km², and 26.05 km² were transferred from the aforementioned three land types to agricultural production land, respectively. Although there was mutual transfer between various forms of ecological land and agricultural production land during this time period, the encroachment of agricultural production land on various types of ecological land was more visible. The phenomenon of deforestation and overgrazing in the Weibei dryland was particularly severe during this time, indicating that the growth in the agricultural production land in the agropastoral ecotone might readily lead to the occupation of various types of ecological land. Furthermore, there was notable growth in rural and urban living lands, which expanded by 160.27 km² and 55.07 km², respectively, and were mostly converted from agricultural production land. Other land use types also had mutual transformations, but the transformation was not obvious. From 2000 to 2020, approximately 1104.15 km² and 3510.24 km² of agricultural production land were converted into forest and pasture ecological lands, and 440.65 km² and 106.94 km² were transferred to rural and urban living lands, respectively. It can be seen from the change in the land use that over this time, the agricultural production land decreased considerably, while both the ecological and living lands increased significantly in the study area. In summary, the transformation of the PLES structure was related to the relevant regional development policies and measures. On the one hand, after the western development plan was put into practice, the scale of urban and rural construction lands in the Weibei dryland expanded more rapidly than before, and the urbanization process accelerated. On the other hand, with the implementation of the concept of ecologically oriented civilizations and the ongoing promotion of the strategy of converting farmland to grassland and forests, the encroachment on ecological land in the study area was contained, and the pasture and forest ecological land types even showed a significant increase.

3.2. The Ecological and Environmental Effects of PLES Land Use Transformation

3.2.1. Spatiotemporal Evolution of the Ecological and Environmental Quality of PLES Land Use

The measurement results from the EQI in different periods of the Weibei dryland indicated that (Figure 3), the pattern of land use change in the Weibei dryland first decreased and then increased when taking the year 2000 as the boundary, and the increase was significantly greater than the decrease. This result shows that although regional ecological improvement and deterioration occurred contemporaneously during this time, the environmental quality of the study area mainly improved. In terms of the periodic variations in the eco–environmental quality, activities such as deforestation and grassland destruction led to a sharp reduction in the ecological land and continuous expansion of agricultural production land during 1980 and 2000 in the Weibei dryland (Table 3). This led to a decrease in the regional EQI from 0.4295 in 1980 to 0.4288 in 2000 (a decrease of 0.07%), and the eco–environmental quality in the Weibei dryland slightly deteriorated during this period. Between 2000 and 2020, affected by the strategy of converting farmland to grassland and forests, as well as the creation of regional ecologically oriented communities, the agricultural production land decreased greatly, and the ecological land increased significantly (Table 4). Consequently, the EQI increased from 0.4288 in 2000 to 0.4365 in 2020 (an increase of 0.77%), which proves that the eco–environmental quality of the Weibei dryland greatly improved during this period.

Taking 50 county–level administrative units in the Weibei dryland as evaluation units, the spatial pattern of the EQI in different periods were delineated by the natural breakpoint method (Figure 4). The analysis revealed that being affected by the distribution of land use types, there was significant spatial differentiation in the eco–environmental quality in the Weibei dryland, which followed the overall distribution pattern of “high in the north and mountains–low in the south and plains”. The highest–quality areas were mainly located in mountainous regions, such as the Huanglong Mountains, Ziwu Mountains, and Qinling Mountains, which is where the forest ecological land was concentrated. These areas not only had high forest coverage but were also limited by unique terrain and geomorphic conditions, and there was little production or living land within the area. Therefore, the eco–environmental quality was the highest in these locations. The higher–quality areas were mostly adjacent to the highest–quality areas. The ecological quality was comparatively excellent, since the pasture ecological land was widely dispersed throughout the region, and the living land and production land areas were dispersed. The lowest–quality areas were distributed zonally and were mainly located in the Guanzhong Plain, where production land and living land were concentrated. These areas showed obvious characteristics of spatial agglomeration and were those most seriously impacted by human activities. Furthermore, the regional ecological environmental quality was the lowest due to the long–term expansion of urban and rural living lands.

3.2.2. Differences in the Rate of PLES Land Use Transformation’s Ecological Contribution

The changed ecological contribution rate can effectively express the impact of different spatial land transfers on regional eco–environmental quality. Therefore, through the calculation of Formula (3), we selected 10 types of spatial land transformation models with obvious impacts on the eco–environmental quality of the study area (Figure 5). From 1980 to 2000, the conversion of pasture ecological land and agricultural production land into forest ecological land was the key element encouraging the improvement in regional eco–environmental quality. Furthermore, the encroachment of agricultural land on pasture ecological land and the degradation of forest ecological land were the main reasons leading to the deterioration of eco–environmental quality. Compared with the previous period, the contribution rate of the transformation of agricultural production land to pasture and forest lands sharply increased from 2000 to 2020, which became the main reason that caused the eco–environmental quality to grow better in the study area during this period. This result indicates that the ecological effect of returning farmland to forest and grassland appeared gradually over time as the policies continued. However, it is worth noting that during this period, the deterioration of the eco–environmental quality driven by the occupation of forage and forestland by agricultural production land far exceeded the ecological benefits brought by returning farmland to forest and grassland. Overall, the developmental trend of the ecological space, such as the conversions of pasture and forestland, was the core factor related to the eco–environmental quality. The expansion (reduction) of ecological spaces improved (decreased) the eco–environmental quality, and the detrimental effect was much greater than the favorable effect. By comparison, the positive effect of pasture ecological land on the eco–environmental quality was strongest, followed by forest ecological land. As a consequence, when pushing a strategy of converting agriculture into forest and grassland, we should combine the unique geographical features of the Weibei dryland to achieve grassland and forest suitability, effectively cultivate and protect ecological land (such as regional pastures and forestland), improve the management and control of land resource spatial usage, and encourage the overall improvement in the ecological environment in the research region.

4. Discussion

Ecological restoration refers to the process of assisting degraded, damaged, or completely destroyed ecosystems to return to a stable, healthy, and sustainable development state, mainly including self–restoration and human restoration [32,33,34]. Due to the extremely slow speed of self–recovery and its long time required for restoration, as well as the restoration process of self–recovery being easily interrupted by the direct or indirect influence of human activities, human restoration is, therefore, an essential means to accelerate ecological restoration. Since the new technological revolution, driven by huge economic benefits, the demand for and exploitation of natural resources in various countries around the world have increased dramatically, bringing a series of ecological challenges to the Earth, such as vegetation destruction, soil erosion, sharp decline in biodiversity, and water shortages [35,36]. Faced with increasingly severe ecological and environmental problems, many experts and scholars at home and abroad have adopted a variety of technical means to restore regional ecological problems using a combination of multidisciplines, multichannels, and multidepartments. Ecological restoration has increasingly become a focus of global attention [37,38]. Since the 1930s, developed countries and regions such as North America and Europe have successively adopted a series of ecological restoration measures to deal with the emerging ecological problems [39,40,41]. In the 1970s, for the purpose of improving the ecological environment in northern China, the Chinese government has listed the “Three North” shelterbelt project as an important project of national economic construction, and to further protect and improve the regional ecological environment, it then launched a comprehensive project of converting farmland into forest at the beginning of the 21st century and has achieved remarkable results [42,43]. In recent years, the protection and improvement in the ecological environment has gradually been carried out nationwide.

The construction of an ecological environment is a complex engineering task. Since the implementation of policies and measures, such as returning farmland to forests or grassland, undertaking natural forest protection projects or pursuing western development, the eco–environmental quality in most parts of the Weibei dryland has improved. However, restricted by the underlying regional natural environment and the level of social and economic development, the study area has not eliminated the overall fragility of the ecological environment. By analyzing the spatial evolution and the changes in the eco–environmental quality before and after 2000 in the Weibei dryland, we divided the study area into four subregions (Figure 6): area of continuous improvement (CI), areas that first deteriorated and then improved (FDTI), areas that first improved and then deteriorated (FITD), and areas that continuously deteriorated (CD). Finally, combined with the specific situation of the subregional ecological environment, we propose some targeted restoration suggestions.

First, for the CI areas, we should pay attention to consolidating the achievements of returning farmland to forest and grassland while safeguarding the local ecosystem, and the structure of production and living land should be modified reasonably. Following this strategy, will ensure the orderly development and comprehensive utilization of these land types. In the study region, these areas are primarily found in the southwest and northeast. Combined with the specific natural geographical conditions and socioeconomic level of the local area, we should strengthen the policies that protect grassland resources on the basis of adhering to the principle of “north grass, south forest”. Additionally, we should encourage the conversion of grain–based traditional agriculture into agricultural systems based on animal husbandry. Similarly, under the premise of protecting the forestland resources in the southwest, the ecotourism industry should be managed according to the level of local economic development. These policies will encourage the continuous restoration of local vegetation and sustainable ecological growth.

Second, for the FDTI areas, we should learn from the lessons of earlier ecological environment deterioration and strengthen the policies protecting the existing ecological environment. Over the past 40 years, the ecological environment construction in these regions has gradually been effective, the environmental quality has improved, and the spatial layout is relatively widespread. For such areas, in the process of pursuing the simultaneous development of the social economy and ecological environment, we should prioritize the preservation of existing ecological achievements and continue to promote the restoration of ecological land. The local ecological industry should steadily grow in tandem with the current state of affairs in order to further improve the ecological environment. For example, the management modes pursuing the development of the characteristic economy and the implementation of agriculture, forestry, and animal husbandry should be combined to promote the regional ecological environment and to encourage the ethical development of the social economy.

Third, for the FITD areas, we should actively strengthen the management and protection of regional ecological land, firmly carry out the policy of converting farmland into forest and grassland and promote the regional ecological environment. These areas are mainly distributed throughout the Guanzhong Plain, where production land and living land are concentrated, and the regional environment is easily disturbed and damaged by human activities. We should pay attention to the effects of human factors on the natural ecosystem and pursue appropriate maintenance and remediation measures, such as prohibiting deforestation, land reclamation, overgrazing, and other acts that damage forest and grassland resources. This includes strictly limiting the massive occupation of regional ecological land as part of the urbanization process to reduce the occurrences of “destruction while governed or already governed but recurring”, which arise during the process of protecting ecological land in the region.

Finally, for the CD areas, for one thing, we should vigorously pursue the restoration of ecological land; for another, we must rationally plan production and living lands and strictly prohibit the occupation of ecological land for the purpose of production and living lands. These areas are mostly found in the central mountainous area and the southern Guanzhong Plain. The ecological forestland of the Huanglong Mountains and Ziwu Mountains dominates the middle mountainous area. As a result, preserving natural grass and forest resources is essential for raising the standard of the local ecological environment. It is necessary to implement forestry logging policies, prohibit indiscriminate deforestation, and even implement remediation measures, such as closing mountains for forest cultivation and banning grazing. The key factor contributing to the declining natural environment is the fast urbanization growth in the southern Guanzhong Plain, where production land and living land are concentrated. Therefore, to restore the ecological environment, it is essential to rationally plan the regional land use types, strictly control encroachment onto ecological land during urban construction, and prevent the large–scale loss of regional ecological land.

In the process of promoting high–quality regional socioeconomic growth and high–level environmental protection, ecological protection must be a priority. The concept that “clear waters and lush mountains are invaluable assets” should be resolutely pursued to promote sustainable regional economic and social development.

5. Conclusions

From the perspective of the transformation of the land use function of PLES and through the quantitative analysis of the EQI of the Weibei dryland from 1980 to 2020, we explored the spatial and temporal changes in land use, as well as the resulting eco–environmental impacts, in the study area in different periods. Furthermore, we offered relevant suggestions regarding the restoration of the ecological environment in different areas.

The conclusions are as follows: (1) The spatial and temporal differences in the PLES land use system in the Weibei dryland were significant. The ecological land was mainly distributed throughout the northern Shaanxi Plateau and Qinling Mountains, and the overall area showed a significant tendency towards expansion, with an increase of 2000.54 km². The production land and living land were mainly centered in the Guanzhong Plain, and the reduction in production land was obviously greater than the increase, with a total reduction of approximately 2866.85 km². However, living land showed a persistent growth trend, with a total increase of 857.17 km² over the past 40 years. Taking 2000 as the boundary, in the early stage, the production and living lands continued to expand, and a large area of ecological land was lost. In the later period, the living and ecological lands expanded clearly, and the production land contracted substantially. (2) The trend of “first declining and then ascending” was evident in the eco–environmental quality curve, both in the improvement and degradation of the regional eco−environment occurred simultaneously. In 1980 and 2000, the ecological environment tended to deteriorate due to the encroachment of agricultural production land on ecological land, such as the conversion of forestland to pastures. From 2000 to 2020, affected by the Grain for Green Project, the eco–environmental quality greatly improved. Concomitantly, the spatial variation in the eco–environmental quality was considerable, and the overall distribution pattern was “high in the north and mountains, low in the south and plains”. The high–quality areas were mainly located in mountainous regions, such as Huanglong Mountains, Ziwu Mountains, and Qinling Mountain, where there was more forest ecological land. The low–quality zones were primarily located in the Guanzhong Plain where production and living land were more abundant. (3) From 1980 to 2000, the degradation of forest land and the encroachment of agricultural production land on pasture ecological land were the main causes of the deterioration of ecological quality. From 2000 to 2020, the primary factor influencing the improvement of eco–environmental quality was the shift from agricultural production land to pasture and forest lands. In the research area, pasture ecological land had the strongest positive effect on the eco–environmental quality, followed by forest ecological land, while the effect of agricultural production land was quite negative. The development trend of the pasture and forest ecological lands was critical to the eco–environmental quality, and the quality of the regional eco−environment was enhanced (degraded) due to the extension (contraction) of ecological land, while the negative effect was obviously stronger than the positive effect. (4) The construction of an ecological environment is a complex engineering task. Although the eco–environment in most of the study area showed an improving trend, the overall eco–environment remains relatively fragile. Appropriate measures should be taken to protect the ecological environment based on the reality of the situations within the four subregions. In the process of promoting the high–quality growth of the social economy and pursuing high–level environmental protection strategies, we should prioritize the protection of the eco–environment. Thus, we should resolutely adhere to the developmental concept of “clear waters and lush mountains are invaluable assets” to promote sustainable regional economic and social development.