**1. Introduction**

Forestry development is related to the sustainable development of China's social economy. Forest resources are pivotal in building ecosystems and improving carbon sink capacity. The role of forest resources in sustainable economic development has attracted more attention from scholars and policymakers. Forest growth plays a very important role in climate regulation [1]. In 2017, the State Forestry Administration issued the "13th Five-Year Plan for Forestry Development" to promote the modernization of China's forestry. In 2021, the "14th Five-Year Plan for Forestry and Grassland Protection and Development Plan" was released. By 2025, China's forest coverage rate will be increased to 24.1%, and the forest stock volume will be increased to 19 billion m3. The Yangtze River Delta (YRD) region is the hub of China's economic development and has an important strategic position in the overall regional development pattern. In June 2016, the "Yangtze River Delta Urban Agglomeration Development Plan" was promulgated. Boosting the construction of a green and low-carbon ecological city has become one of the important goals of the integrated development of the YRD. In 2018, the integrated development of the YRD was officially elevated to a national strategy. From 2000 to 2018, the forest coverage rate in the YRD region increased from 22.29% to 29.33%, much higher than the national average. However, the distribution of forest resources is uneven, and the structure is unreasonable. During the same period, the economic development of the YRD region was higher than the national average level and showed obvious regional differences. In December 2019, an Outline of the Yangtze River Delta Regional Integrated Development Plan was issued to

**Citation:** Zhang, Q.; Tang, D.; Boamah, V. Exploring the Role of Forest Resources Abundance on Economic Development in the Yangtze River Delta Region: Application of Spatial Durbin SDM Model. *Forests* **2022**, *13*, 1605. https://doi.org/10.3390/f13101605

Academic Editors: Noriko Sato and Tetsuhiko Yoshimura

Received: 31 August 2022 Accepted: 28 September 2022 Published: 30 September 2022

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prioritize ecological protection and strive to build a beautiful Yangtze River Delta. In the 14th Five-Year Plan of each province and city, increasing forest coverage has become one of the common goals for all the cities in the YRD. The YRD region is a cluster of 41 cities in 1 municipality (Shanghai) and 3 Provinces (Jiangsu, Zhejiang, and Anhui) [2,3]. Figure 1 shows the location of the YRD region.

**Figure 1.** Location of the YRD region [4]. Reproduced from [4], with permission from Scientific Research Publishing, 2020.

There may be a phenomenon of "tragedy of the commons" for forest resources. One of the reasons for this phenomenon is that the beneficiaries of the use of resources and services do not need to pay for it. The costs and benefits are not equal. Unfair allocation of resource property rights will affect the fairness and efficiency of resources and social benefits and may lead to resource rent-seeking and corruption [5]. The resource curse can be turned into welfare if resources are effectively managed [6].

Some scholars have studied whether the environmental Kuznets curve (EKC) exists between forest resources and economic development, but the conclusion is also controversial [7–9]. The EKC assumes an inverted U-shaped relationship between economic growth and environmental quality, which means a country or region's environmental quality will decrease with economic development. Still, when the economy develops to a certain level, the environmental quality will gradually improve [9]. Therefore, this paper's motivation is to empirically explore the impact on the economy at different stages of forest resource development in the YRD region.

This paper mainly studies the following questions: (1) Does the abundance of forest resources in the YRD promote economic development at the city (city in this paper includes urban and rural areas) level? (2) Is there any non-linear relationship between the two? (3) Is there any evidence of the spatial spillover effect? (4) Can the abundance of forest resources improve green total factor productivity? (5) Does economic development affect forest growth, and does the Environmental Kuznets Curve exist? The possible academic contributions of this paper include: (1) Based on the resource curse hypothesis, the impact of natural resources on economic development is discussed from the perspective of renewable resources. (2) Both the quantity and quality of economic development are considered. GDP per capita (although GDP is national and gross regional product (GRP) is regional, GRP is conceptually equivalent to GDP [10]. For readers to understand easily, the term "GDP" is still used in this paper instead of "GRP") and the green total factor productivity are analyzed further to comprehensively measure the economic development level of the YRD region. (3) This paper adopts a spatial econometric model, which not only considers general economic and social factors but also takes the spatial factors into account. The research in this paper complements the existing literature and provides a reference for policymakers.

The paper is structured as follows. Section 2 presents the literature review. Section 3 presents the econometric models, data collection, and categories of the variables. In Section 4, we describe the model estimation's main results, including direct effects, spatial spillover effects, the robustness check, and reverse causation. In Sections 5 and 6, we discuss the results and then draw the main conclusions.

#### **2. Literature Review**
