1. Introduction
Many social challenges humans face are closely related to the scarcity of available land resources and the contradiction between land supply and demand, such as food security and ecological damage [
1]. Territory spatial planning helps improve land quality and land use efficiency [
2] and is considered an essential tool for achieving global sustainable development [
3]. With the progress of the Global Land Project (GLP), conducting territory spatial planning from the standpoint of social-ecological interactions, such as providing ecosystem services, has become a focal topic [
4]. Territory space refers to the regional space under national sovereignty and jurisdictional rights. It is the carrier of ecological resources and the place for human production and living. Territory spatial protection and governance help coordinate human development activities, protecting ecological resources and becoming the fundamental basis for various land resource development [
5]. Ecosystem services can reflect the ecological functions of territory space, but the ecological function damage caused by human over-exploitation has affected ecosystem services [
6]. Therefore, ecosystem services should be incorporated into territory spatial protection and governance to protect ecological resources and achieve human well-being.
The concept of ecological products was initially introduced by China in 2010 as an enhanced iteration of the notion of ecosystem services, and its primary objective was to address the protection and governance challenges related to territory space [
7]. Human activities and ecological systems are the basis of ecological product supply. Promoting territory spatial protection and governance by improving the ecological products supply is very important. China has adopted holistic and systematic thinking to organically combine the original economic social development and land use planning, forming a "multiple planning in one" territory space planning [
5]. The Guidelines for Pilot Work on the Value Realization Mechanism of Ecological Products in the Field of Natural Resources issued by China in 2021 explicitly state that evaluate the ecological products evaluation and promote the ecological products supply in territory spatial planning. In view of this, ecological product supply provides a powerful perspective for territory spatial protection and governance and can serve as a research carrier for land resource allocation and spatial interest coordination, further promoting high-quality development. The Beijing-Tianjin-Hebei Coordinated Development Strategy plays a leading and exemplary role in coordinating the development of land and ecological environment in China. It is necessary to evaluate and analyze the ecological product supply capacity in the Beijing-Tianjin-Hebei region to discuss the protection and governance strategy of the territory space.
Previous studies have focused on improving the ecosystem services to guide territory spatial protection and governance, but there has been relatively little research on ecological product supply. By exploring the role of ecosystem services in multiple urban planning documents, it was found that incorporating ecosystem services into territory space planning helped protect the environment and meet the needs of various stakeholders [
8,
9]. Interviews of the values of local authorities and stakeholders regarding the inclusion of ecosystem services in spatial planning indicated that people generally recognize its usefulness [
10,
11]. Some scholars have quantified and predicted the benefits of incorporating ecosystem services into land use governance [
12], green infrastructure planning [
13], and biodiversity protection [
15]. The effectiveness of land conservation policies, such as ecological compensation and restoration, has been evaluated. Spatial assessment and planning have been conducted by mapping ecosystem services' demand, flow, and capacity [
16]. Although previous research has confirmed ecosystem services have theoretical and practical support in territory space planning, the application of territory space supply in territory spatial protection and governance was unclear. Implementing territory space supply in territory spatial protection and governance lacked pre-planning and overall planning [
17]. It is necessary to explore the basic evaluations, development directions, target indicators, and spatial guidance of ecological product supply. In addition, there are many ways to promote territory spatial protection and governance through ecological product supply, such as managing natural resource assets [
18], spatial zoning classification for territory space regulation [
19], and ecological restoration of territory space [
20].
For territory space planning in China, it is urgent to clarify the connotation and classification of ecological product supply, connect with the needs of territory spatial planning, and play a role in territory spatial protection and governance. Internationally, ecological products are defined similarly to ecosystem services, which pertain to the environmental conditions and benefits that ecosystems provide and sustain for human survival and development [
21]. In China, ecological products denote ecosystems' products and services for human well-being [
22]. While scholars have different perspectives on ecological products, it is generally understood as a term encompassing the products and services arising from the interaction between natural ecology and human society, ultimately leading to improving human well-being. Many researchers have classified ecological products from different perspectives: according to the degree of human social participation, ecological products were divided into natural element products, natural attribute products, ecological derivative products, and ecological label products [
23]. According to the social needs of humans, ecological products were categorized into public, quasi-public, and commercial ecological products [
24]. Based on their ecological attributes, ecological products were further divided into material products, ecological regulation service products, and cultural service products [
25].
The ecological products supply capacity refers to the ecosystem's ability to provide ecological products and services within a defined time and space range [
26], and there is no unified understanding and standards for its evaluation indicators and methods. The most representative indicator systems include the system constructed by Costanza [
27], which consists of 17 categories, such as climate and gas regulation. The Millennium Ecosystem Assessment report proposes four categories: provisioning, regulating, supporting, and cultural services [
28]. The Common International Classification of Ecosystem Goods and Services (CICES) classified it into material supply, regulation, and cultural services [
29]. Some scholars have established an indicator selection framework comprising ecological service attributes, functions, and services [
30]. Currently, the assessment of ecological products can be measured in terms of functional and value quantity. Functional quantity represents the quantity of ecological products formed by ecosystem functions, such as food production, water supply, pollution purification, soil conservation, and tourist numbers. It is intuitive and concrete, but due to different units of measurement, it is difficult to add up the output and service of different ecosystem products. Value assessment methods are the earliest and relatively mature, which include the equivalent factor method [
27], the direct market valuation method [
31], and the contingent valuation method [
32]. The direct and contingent market valuation methods determine the value of ecosystem services by considering market prices that reflect different human preferences. The equivalent factor method utilizes an ecosystem service values equivalent table to combine various land ecosystem service functions and the area of different ecosystem types, thereby obtaining the total service value of the research area. In China, the equivalent factor method is extensively used, particularly in land use cover change assessments. The studies above have provided crucial theoretical support for establishing evaluation indicators and methods for assessing the ecological product supply capacity.
So far, research on how ecological product supply promotes territory spatial protection and governance has made substantial progress, but there are also some shortcomings: (1) the research on territory spatial protection and governance from the perspective of ecological product supply is still in the exploratory stage. (2) The quantitative indicators and evaluation methods for ecological product supply capacity must be improved. So, we developed an evaluation index system for the ecological product supply capacity to address these two issues. By utilizing data from 13 cities in the Beijing-Tianjin-Hebei region spanning from 2011 to 2021, we quantified the level, spatial-temporal pattern, and obstacle degree of ecological product supply capacity. We found that the supply capacity of ecological products showed an increasing trend; different types of ecological products varied across cities and over time, exhibiting noticeable spatial differentiation. Obstacle factors affecting supply capacity included eco-land, eco-tourism, eco-leisure, park green space, and fishery products, although there were variations among cities. Then, we analyzed the strategy to promote territory spatial protection and governance from the perspectives of integrated protection of elements, structural regulation, and systematic governance. The research has the following significance: (1) identifying the differences in each category's ecological product supply capacity in the Beijing-Tianjin-Hebei region. (2) proposing strategies for territory spatial protection and governance from the ecological product supply perspective expanded the territorial space planning research perspective. (3) providing China's example for global sustainable development, especially providing spatial planning guidance for sustainable development in regions with a spatial imbalance between ecological resources and economic development.
The rest of the structure is as follows.
Section 2 introduces the research area, data sources, and the workflow of processing ecological products supply indicators and data, then presents the index system and methods.
Section 3 analyzes the results.
Section 4 discusses the Strategies for territory spatial protection and governance to enhance the ecological products supply capacity.
Section 5 presents the research conclusions.
4. Strategies for Territory Spatial Protection and Governance to Enhance the Ecological Products Supply Capacity
Ecological products are based on natural resources and shaped by human society, with the territory space acting as the platform for natural resources and human development (Figure 7). The objective is to increase the availability of ecological products to safeguard and manage the territory space. Natural resources are the fundamental components of ecological product supply, possessing characteristics of resources, assets, and capital. The key to ensuring a steady supply of ecological products lies in the responsible preservation and utilization of natural resources, encouraging the transformation of ecology into valuable assets and capital to fulfill the requirements of human society. In the ecological products supply, the protection and management of territory space reflect the asset management thinking of natural resources, providing the following protection and management paths: protecting and restoring natural resources, classifying and zoning the management of ecological resources, providing a space for trade circulation, and implementing safeguard policies. These path implementation requirements include integrated protection of elements, structural regulation, and systematic governance. The interaction between human society and the ecological environment creates different types of functional spaces [
50], and the characteristics of the ecological products as a product of human and biological joint action on the ecosystem reflect the utilization of territorial space elements, functional structure, and system status [
51]. Therefore, it is possible to enhance the level of supply capacity, spatio-temporal pattern, and obstacle factors of ecological products and construct strategies for protecting and governing territory space from the three aspects of integrated protection of elements, structural regulation, and system governance.
Figure 6.
Analysis for territory spatial protection and governance based on ecological products supply.
Figure 6.
Analysis for territory spatial protection and governance based on ecological products supply.
4.1. Integrated Protection of Territorial Spatial Elements for Enhancing the Ecological Products Supply Capacity Level
The integrated protection of territory spatial elements considers the ecosystem of mountains, rivers, forests, fields, lakes, grasslands, and deserts as a whole. It requires relying on each city's advantages of ecological product elements endowment to maintain and enhance the regional ecological system. The endowment of ecological elements determines the foundation and characteristics of ecological product supply, with wind and water serving as natural media that connect various ecological elements. Therefore, the BTH region should rely on the endowment of ecological elements such as forest land, grassland, and cropland to plan and design integrated protection based on production products such as fresh air, organic agricultural products, natural ecology, and landscape culture.
The characteristic elements of ecological product supply in the BTH region are located at the Yanshan and Taihang Mountain areas, involving Zhangjiakou and Chengde; the grassland area in the northwest of Zhangjiakou; the ecological tourism area of Beijing and Tianjin; the ecological agriculture area of Beijing Tianjin, and Tangshan; the western regions of Shijiazhuang, Xingtai, and Handan; the mountainous and hilly ecological transition zones in the western parts of Handan and Hengshui; as well as the agricultural ecological zone in the North China Plain [
52]. Chengde and Zhangjiakou cities should develop ecological tourism and animal husbandry based on natural ecosystems such as forests and grasslands, forming several forest parks and grassland parks as nature reserves [
53]. Important ecological tourism areas such as Beijing, Tianjin, and Shijiazhuang should ensure the supply of ecological land, such as forest areas and wetlands, and improve the ecological environment to guarantee the conditions for ecological tourism. Tangshan, Cangzhou, Hengshui, Xingtai, and Handan should make use of a large amount of cropland and agricultural products to develop eco-agriculture and agricultural tourism. In ecologically excessive hilly areas, both oasis protection and farmland protection and afforestation should be considered, forming mixed vegetation to ensure the sustainable development of agricultural ecological obstacles [
54].
4.2. Regulation of Territory Spatial Structure based on Differentiated Parrern of Ecological Products Supply Capacity
Disorderly use of territory space structure can lead to conflicts between land use patterns and ecological functions [
55]. We should rely on the differences in ecological product supply types in each city and layout production, living, and ecological space according to the structure regulation of territory space function. The division of "three spaces" and three ecological product categories coincide, but in this study, production space aims at agricultural production and food security, living space involves maintaining residents' living environment and leisure, and ecological space aims at maintaining ecological system stability. Regions such as Cangzhou, Hengshui, Xingtai, and Handan, which have a higher concentration of agricultural production, should prioritize the protection of permanent basic farmland. They should also make full use of the advantages of flat and contiguous land, promote mechanized agricultural production, and utilize the scientific and technological expertise and talent advantages of Beijing and Tianjin. There should be a shift in the development focus of major agricultural product areas toward providing high-tech and high-quality ecological materials. Living space is mainly located in the southeast plain area, including Beijing, Tianjin, Langfang, Shijiazhuang, and other metropolitan areas. We should promote urban public green space and infrastructure construction. Ecological space is mainly located in Chengde and Zhangjiakou, and we should strictly abide by ecological protection [
50].
The problem of mismatch between ecological product supply and demand is widespread. We should explore cross-regional circulation and trading models of ecological products to regulate the structure of territory space [
34]. Regions with advantages in ecological product supply are usually dominated by mountains and plateaus, with low population density and small consumption of ecological products. Most areas in the BTH region are plain areas, where population density and demand for construction land are large, inevitably leading to insufficient ecological product supply. These problems inevitably promote the existence of cross-regional ecological product supply. Cities in the northern part of the BTH region, such as Chengde and Zhangjiakou, are regions with advantages in ecological environmental product supply compared to cities in the southern part. The ecological product value should be calculated, and compensation standards should be determined. Beijing and Tianjin, along with other areas benefiting from fresh air and clean water sources, should pay compensation fees or compensate the areas supplying ecological products through ecological taxation. Tangshan, Cangzhou, and Hengshui, with advantages in ecological material products supply, can improve market transaction prices by adopting ecological labeling certification methods or promoting the sale of local green products through green procurement and policy subsidies, transferring the ecological protection costs and other additional costs in product production to the consumer area.
4.3. Systematic Governance of Territory Space for Addressing the Ecological Products Supply Capacity Obstacle Factors
The ecological product supply obstacle factors in the BTH region are the basis for the governance of the territory spatial system, which helps to form a global and specific system governance plan. The ecological cultural products in the BTH region face the greatest obstacles. Essential factors hindering development include fishery products, park green space, eco-leisure, eco-tourism, and eco-land. So, Ecological construction should be strengthened throughout the region, with overall planning for native vegetation and traditional village ecological landscapes, to promote the transformation and realization of the value of ecological spaces and eco-leisure resources[
52].
In addition, Each city should strengthen actions such as greening land and space, environmental governance, restoration of mines, and returning cultivated land to forests, grass, and water. As well as enhance the reclamation and remediation of land while increasing the area of ecological land and urban park green spaces. For example, Beijing, Tianjin, and Tangshan should strengthen mountain restoration and afforestation, protect water areas and wetlands, and develop ecological agriculture; Chengde and Zhangjiakou should deepen the governance of sand and dust sources in the Beijing-Tianjin region, expand green spaces, and carry out projects such as mountain closure and afforestation of barren mountains to increase the area of urban park green spaces; Shijiazhuang and Qinhuangdao should rely on the beautiful natural environment to construct park green spaces and improve the quantity and quality of forests; Baoding, Handan, and Xingtai should focus on the restoration of mountain coverage, and continue to prevent soil erosion and vegetation destruction; Langfang, Hengshui, and Cangzhou should be highly vigilant against non-food production and occupation of cropland, and carry out urban ecosystem integration governance[
54].
5. Conclusions
Previous studies have emphasized the guiding role of ecosystem services in land resource development, but these studies have paid less attention to ecological products or have not explored territory protection and governance strategies based on the ecological product supply. This study combined the characteristics of ecological products and the ecological, productive, and living functions of territory space to construct an evaluation index system for the ecological products supply capacity. Taking the BTH region as an example to comprehensively apply principal component analysis, equivalent factor method, and entropy value method to evaluate the supply capacity from 2011 to 2021. Furthermore, the study analyzed the spatio-temporal patterns of ecological product supply using the natural breaking point method and quantile classification method and analyzed obstacle factors using the obstacle degree model. Finally, based on the level, pattern, and obstacle factors of ecological product supply, we proposed suggestions for territory spatial protection and governance from the aspects of integrated protection of elements, structural regulation, and systematic governance.
The main findings are as follows: (1) The overall supply capacity of ecological products in the BTH region showed an increase in 2011-2021. The highest availability was ecological environmental products, while ecological material products had relatively lower availability. The category with the highest growth rate was ecological cultural products. (2) The availability of ecological products in different cities of the BTH region has been consistently increasing from 2011 to 2021, but the trends of different categories of ecological product supply capacity varied over time. There were significant spatial differences and prominent regional advantages. (3) The supply of ecological cultural products directly impacts the overall supply capacity of ecological products, and the obstacle factors to the ecological product supply were relatively stable, mainly concentrated in factors such as eco-land, eco-tourism, eco-leisure, park green spaces, and fishery products There were specific differences in these factors among different cities.
Based on the analysis of the ecological product supply capacity level, pattern, and barrier factors, it is necessary to propose policy recommendations for territory spatial protection and governance from the aspects of integrated protection of elements, structural regulation, and system governance. (1) The integrated protection of territory spatial elements requires relying on the advantages of ecological product elements endowment in each city to improve the regional ecological product supply. (2) Based on the variations in the types of ecological product supply in each city, the ecological space should be planned according to the idea of optimizing the overall structure of land space function. The optimization of territory space structure can be based on providing material production, cultural life, and ecological environment functions. (3) The BTH region should strengthen the construction of ecological culture, plan the ecological landscape of native vegetation and traditional villages as a whole, and promote the value of beautiful ecological spaces and ecological leisure cultural resources. Each city should also explore differentiated system governance strategies based on its barrier factors.
This study expanded previous research on ecological products and established an evaluation index system for ecological products that considered the ecological function of the territory space. We also proposed territory spatial protection and governance strategies from the perspective of ecological product supply. This study helps to improve territory spatial planning from the perspective of ecological environment protection. It provides references for ecological product supply and territory spatial planning in China and offers optimized strategies for land resource allocation and spatial coordinated development for sustainable development in some regions. However, various evaluation methods exist for ecological product supply, and territory spatial protection and governance have complexity. On the one hand, ecological product classification, value accounting, and the realization of value transformation can all affect the evaluation results of ecological product supply. Different indicators and methods may lead to different evaluation results. On the other hand, there may be inconsistencies between ecological product supply and territory spatial protection and governance behaviors due to the incomplete economic rationality of ecological product suppliers when facing complex economic and social information. Therefore, in future research, (1)we should further explore the comprehensive set of indicators and corresponding accurate calculation methods. (2) to strengthen the analysis of ecological product demand and the analysis of incentives for ecological product supply in ecological product supply analysis. (3) it is also important to delve into the cognition and behaviour of ecological product suppliers and territory spatial protection and governance entities, seeking a balance and consistency between product suppliers and territory spatial protection and governance entities.