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Abstract

The “Belt and Road Initiative ” (BRI) was anticipated in 2013 to promote socio-economic development and cooperation across countries in Asia, Europe, Africa and worldwide. Rapid land-use changes and infrastructure developments driven by the BRI program are expected in the coming decades. These anthropogenic effects are likely to exaggerate the process of de-vegetation, deforestation, accelerating desertification, which is one of the major threats to the BRI region. This manuscript studied the desertification facts (i.e. spatiotemporal pattern, impacts and impacting factors) and investigated key aspects for desertification control (i.e. mitigation and evaluation methods) in the BRI countries via an extensive review of literature. We found that desertification has been prevalent in the BRI countries, predominantly in C Asia, but quantitative assessment of desertification is yet fully understood. This review illustrated that desertification was driven by climatic dryness and mis-land-use/management activities, but their relative importance has yet been (quantitatively) assessed along the BRI countries. Given the negative impacts of desertification, these BRI countries have ratified the UN Convention to Combat Desertification (UNCCD) to reduce negative impacts. The implementation of desertification mitigation programmes are currently still lacking. We argued that desertification is usually evaluated via four type of approaches, including quantitative approaches, indirect detection, direct observation and biophysical measurement (e.g. vegetation growth). Future research should be applied by considering the research scope and data availability. Overall, we conclude that BRI countries should carry out transboundary control on desertification. Otherwise, this issue is likely to extend further imminent developments under the foremost BRI program.
Keywords: dryland degradation – impacts – causes - mitigation – evaluation – Belt and Road Initiative (BRI)

1. Introduction

The “Belt & Road Initiative ” (BRI) (“一带一路” in Chinese ), initiated in October 2013 by China (Wang, 2013, Ascensao et al., 2018), is the biggest trans-national program, which accounts for up to 64% of global population and 30% of Gross Domestic Product(GDP) across the world (Huang, 2016, Economist, 2016). While infrastructures development (e.g. railway, highway constructions) taking on a leading role (Lechner et al., 2018), the BRI also comprises of inter-connections on dialogues, trades, scientific and technological knowledge exchange, education and talents developments (Huang, 2016, NDRC, 2015). Since the BRI initiated, it has contributed considerably to the cross-country cooperation that was firstly promoted within Asia and then extended to Europe, Africa and other continents (Irshad et al., 2015, Turgel et al., 2017, NRSCC, 2015). This policy encourages the transnational financial and trade cooperation, evidently by founding the “Asian Infrastructure Investment Bank ” (AIIB) (headquartered in Beijing) (Yu, 2017) and establishing the “Silk Road Fund ” in the last few years (Fallon, 2015). The BRI program is undoubtedly beneficial for the socio-economic development of Asia Pacific, Central Asia, Middle East, Europe, Africa and worldwide (Ascensao et al., 2018), promoting over a quarter of global trade in the coming decades (Konings, 2018).
Although benefits of the program are expected, uncertainties and challenges associated with the BRI are potentially seen, such as the adverse impacts on ecosystem services, biodiversity and environment (Lechner et al., 2018, Ascensao et al., 2018, Hughes et al., 2020). Most of these areas located within or besides the BRI’s Economic Corridors (ECs) (e.g. Central Asia, Middle East, etc.) are categorised as high ecologically sensitive areas (e.g. wetlands, lakes, forest, etc.), which have vibrant ecological species, valuable landscapes and vegetation. Rapid development and investment projects in these ECs may degrade the eco-environment and lead to further exaggerated desertification in drylands and arid regions (Ascensao et al., 2018).
The term ‘desertification ’ was firstly used to depict the transfer of productive arable lands in West Africa to deserts in the 1920s (Kertész, 2009). In the 1970s, the “United Nations Conference on Desertification” (UNCOD) was organised following the extremely arid/dryness periods from 1950s to 1970s in the region of Sahelian Africa (Kertész, 2009). “Desertification ” was defined in the conference as, “Reduction or destruction of the land’s biological potential, which eventually results in the initiation and development of desert-like conditions ” (UNCOD, 1977). In the 1990s, the “UN Convention to Combat Desertification ” (UNCCD) further defined “Desertification ” as, “Land degradation in arid, semiarid, and dry sub-humid areas ” (Helldén and Tottrup, 2008, D’Odorico et al., 2013). That is to say, ‘Desertification’ refers to land degradation in drylands, which generally include “hyper-arid ”, “arid”, “semi-arid ” and “dry sub-humid ” areas with precipitation being largely counterbalanced by evapotranspiration (Middleton and Thomas, 1997), excluding hyper-arid areas. Recently, the UNCCD definition of desertification has been challenged as overexploitation of water resources in hyper-arid lands fits well into the concept of desertification, suggesting the necessity for a further expansion of the UNCCD definition to include hyper-arid areas (Martínez-Valderrama et al., 2020).
Drylands support global populations at 38% (Huang et al., 2015), about 90% of which is currently living in the “Global South ” and “developing countries ” (D’Odorico et al., 2013). However, these areas are subject to land degradation (Bai et al., 2008), which is mainly driven by desertification (Bayram and Öztürk, 2014). Dryland degradation (i.e. desertification) extensively cost the developing countries at about 4–8% of their GDPs (D’Odorico et al., 2013); further exacerbating local poverty and episodic mass starvation (UNCCD, 2011). This factual impact provided that the Dryland (and specifically the developing countries in Dryland area) is likely subject to an increasing desertification and land degradation according to human-induced and climatic factors (Huang et al., 2015, Huang et al., 2020). However, desertification of dryland area has not attracted as much public and scientific attention as other major environmental issues such as climate change and biodiversity loss (Martínez-Valderrama et al., 2020).
In fact, the BRI is currently covering a large proportion of areas classified as drylands (Figure 1), where desertification is flattering to expand as vegetation (e.g. suburbs, trees and plants, etc.) is difficult to survive (Feng et al., 2015). Desertification has turned into a significant land degradation problem in the geographical regions that have been engaged with the BRI program, particularly in the “Belt ” terrestrial routes and economic corridors (Dregne, 2002, Dregne and Chou, 1992). For example, in Central Asia (Behnke, 2008, Liu et al., 2004, Jin et al., 2012, Jiang et al., 2019a, Jiang et al., 2019b), North China (Wang et al., 2008, Xu et al., 2019a, Xu et al., 2019b) and Western Asia (Haktanir et al., 2004, EI Shaer, 2015, Darwish et al., 2004, Bayram and Öztürk, 2014, Amin, 2004, Alvi, 1995, Gul et al., 2019).
Natural and human-induced processes are widely acknowledged driving forces for desertification (Feng et al., 2015, Sun et al., 2019), including climatic change, water and wind erosion, over-grazing and excessive farming activities (Dregne and Chou, 1992, Zhang and Huisingh, 2018). For example, climate change may exert adverse effects on the dryland environment (e.g. vegetation growth, hydrological cycle) and eventually lead to a further expansion of the desertified area (Marland et al., 2003, Wang et al., 2004, Zhou et al., 2009, Huang et al., 2015, Zhang et al., 2020a). Mis-land-use/management, such as over-grazing, logging, underground water exploitation, inevitably eliminates vegetation that prevent soil erosion by intensive rainstorms and strong winds, eventually threating regional ecosystems and largely accelerating the desertification (Zhao et al., 2005, Zheng et al., 2006, Zhang et al., 2020b).
Future developments under the BRI program will likely lead to substantial land-use changes and infrastructure constructions, which facilitate further expansion of deforestation, de-vegetation and green spaces shrinkage. These human-induced developments will interfere the dryland environment and spread out the risk of desertification, particularly given the fact that the BRI policies and practices have been executed between East Asia (includes China), Central Asia, West Asia and Eurasia regions (NDRC, 2015, Hughes et al., 2020). The comprehensive desertification control measures are thus required under the BRI program to promote the eco-environmental protection in all countries that joined the program unanimously. These measures should be established; on top of an exhaustive understanding of desertification, such as the potential impacts and driving forces. Evidently, the Chinese Government has recognised to implement the ecological friendly programs that include the “Ecological Civilization ” program (Lechner et al., 2018). Recently, the Government has further pushed the sustainability practice in the BRI program and established the “Green Belt Development ” practice (e.g. promoting using green finance, and encouraging green energies) that aims to achieve Low Carbon and Sustainable Development Goals (Liang and Zhang, 2019).
In this paper, we aimed to review and investigate the desertification and its control measures in the BRI countries. Based on extensive review of literature (e.g. journal articles, books, conference papers, reports), we systematically investigated the desertification situation (i.e. spatiotemporal pattern, impacts, impacting factors), and key components for desertification control (i.e. mitigation and evaluation strategies). We provide some solutions and policy recommendations that aim to offer ways to mitigate the desertification in the BRI countries.

2. Geographical domain of the BRI region

The BRI program is predominantly focused on the ECs and specific development areas (Lechner et al., 2018, Menhas et al., 2019). On the terrestrial areas, it focuses on building several economic corridors, namely, the “Eurasian Land Bridge Economic Corridor ” (ELBEC), the “China-Mongolia-Russia Economic Corridor ” (CMREC), the “China-Central Asia-West Asia Economic Corridor ” (CCAWAEC) and the “China-Indochina Peninsula Economic Corridor ” (CIPEC) (Figure 1). At Maritime (coastal) environment, the BRI program concentrates on developing the “China-Pakistan Economic Corridor ” (CPEC) and the “Bangladesh-China-India-Myanmar Economic Corridor ” (BCIMEC). The intention of developing the corridors is to promote further development of the BRI through a multi-functional approach (Narain et al., 2020), which is established and combined with international trans-national freight logistics and transport routes, key cities to enhance new developments and infrastructures (i.e. industrial parks) in the BRI region.
Four out of the above six ECs are facing drought threats, including CMREC, CCA-WA-EC, ELBEC and CPEC (NRSCC, 2015) (Figure 1). Some countries located in the dryness regions, such as Kyrgyzstan, Mongolia, Pakistan, and Egypt, are suffering from severe drought effects due to lacking of adequate water resources under the aridness climatic pattern. In addition, these areas are also comparatively sensitive to climatic change and anthropogenic (human-induced) interventions (Huang et al., 2015) (Figure 1). Dryland degradation (i.e. desertification) is currently widespread in the BRI region, which requires more attention put into practice of the BRI program.