## 2 The Relationship between Ecosystem and Socio-Economic Status  
Previous studies have evaluated the effect of economic growth on environmental restoration [31; 32]. As a commonly-accepted approach, the environmental Kuznets curve (EKC), represented by inverted U-shape curves, was usually adopted to explain the theoretical relationship between per capita income and environmental quality [33; 34]. This approach originally hypothesized that economic development leads to decreasing economic inequality. However, in terms of the ecosystems and environment, conservation and recovery due to economic growth have been limited due to various drivers from each sector. Therefore, it has been challenging to determine exact inflection points in the EKC. With the uncertainty in coordinating environmental decision-making based on economic factors, a comparison of economic and forest stock changes was proposed [35]. Although in-depth analysis was limited with this approach, the ECK research has provided a theoretical background and motivations for considering economic factors with natural environmental quality and developing the LDPs concept. Regardless of these challenges, evidence for correlated ecosystem restoration and economic growth is exemplified in some regions, such as the Korean Peninsula. Based on forest restoration history, the Republic of Korea (South Korea) and the Democratic People's Republic of Korea (North Korea) had different political, economic and environmental pathways. Notably, serious environmental degradation has been reported since the 1990s in North Korea, which resulted in forest degradation and decreasing net primary productions [36; 37; 38]. In contrast, forest stock in South Korea has increased since the 1970s with proper forest management and restoration activities [39]. A quantitative comparison of the two countries based on gross domestic product (GDP) per capita data from the World Bank and forest stock data from 1960-2010 provided by the Korea National Institute of Forest Science (NIFoS) is shown in Figure 1[40; 41]. The relationship between GDP growth and forest stock changes in South Korea and North Korea represents positive evidence between environmental restoration and economic development. Although there are many factors that affect GDP per capita and forest growth, we can infer that economic growth has a positive impact on environmental restoration capacity [40]. To expand the regional scales to the Mid-Latitude region and global scale, global \(1^{\circ}\) forest stock data were adopted to figure out the relationship between GDP and forest stock change [42]. Data were compared based on five-year averages, and the relationship between GDP growth and forest stock changes showed differing results depending on the country. In France, forest stock increased rapidly with increasing economic GDP per  
Figure 1: Relationship between GDP per capita and forest stock on the Korean Peninsula: (**a**) South Korea; and (**b**) North Korea. capita. In contrast, a clear relationship was not identified in China, Iran and Iraq. The forest stock of these countries fluctuated, and GDP per capita grew rapidly after the 2000s (Figure 2). Such results provide important evidence of the connection between environmental status, represented by forest stock, and socio-economic status, represented by GDP per capita. Canada, Germany, USA and Italy had similar patterns as the French case. China had converted its industrial structure after the 1970s, and GDP per capita increased rapidly after the 2000s. Iran also showed increasing GDP per capita after the 2000s, but an economic recession occurred from the late 1980s to the 1990s. There was a time gap between economic recession and a decrease in forest stock. Afghanistan also showed a similar pattern as Iran, but we could only compare forest stock changes because of missing GDP per capita data from 1980-2005. Trends characterized by variable economic status were also found for Pakistan, Greece, Tunisia and Iraq.