Vegetation Dynamics Due to Urbanization in the Coastal Cities along the Maritime Silk Road

Abstract

Substantial research indicates the effects of urbanization on vegetation cover; however, a view of this scenario from a regional scale is absent. Nowadays, coastal cities have become the new engine for the development of countries in coastal areas. To capture the effects of rapid urbanization on vegetation dynamics, 35 coastal cities along the Maritime Silk Road (MSR) were selected to study the related research using quantitative tools. We calculated spatiotemporal trends of vegetation dynamics along an urban development intensity (UDI) gradient using the MODIS-enhanced vegetation index (EVI) during the period of 2000–2015. We found a significant reduction (p < 0.05) in the EVI in the core area against that in the rural area (ΔEVI) of 14 cities and an insignificant change in vegetation in the peri-urban areas or urban outskirts. EVI decreased significantly along the UDI gradients in 12 coastal cities with a linear pattern and in seven coastal cities with a concave pattern; only Bangkok exhibited a convex pattern. The nonlinear pattern between the EVI and UDI reflected the fact that vegetation dynamics were affected by complicated factors, including climate change and human interventions, over a long period of time. In conclusion, our work provided a scientific reference for the sustainable development of coastal cities along the MSR; further work is necessary to explore the mechanic details of the positive and negative influences of urban factors and related policies on vegetation conditions.

Status and Prospect of Ecological Environment in the Belt and Road Initiative Regions

“…In addition, the sources of major tsunamis are the several large tectonic faults on the Maritime Silk Road, most of which are located in the northwestern Pacific Ocean and the northeastern Indian Ocean, making tsunami events mainly distributed in the South China Sea, the eastern Indian Ocean, the Arabian Sea and the Mediterranean coast [ 37 , 42 ]. Meanwhile, human activities, such as rapid urbanization, often result in abrupt land-use changes that lead to eco-environment degradation, including vegetation reductions, increased coastal erosion and reduced ecosystem diversity [ 47 ]. Given that the Belt and Road regions are mainly ecologically fragile areas with complicated, diverse and vulnerable eco-environmental conditions [ 48 ], the eco-environmental issues along the BRI regions are worthy of in-depth study for the future formulation of countermeasures and eco-environmental protection strategies.…”

“…Terrestrial vegetation enacts an important role in ecosystems, such as mitigating global warming, preventing soil erosion and alleviating city heat islands [ 47 , 49 , 50 ]. Coastal vegetation, including mangroves, salt marshes, macroalgae, seagrasses, coastal strands and dunes, also buffer shores and retain sediments from tides, waves and storms [ 47 ]. However, the vegetation coverage in the Belt and Road region has experienced a significant change in recent years.…”

“…Nevertheless, the northwestern part of Central Asia struggles with infrequent rains, poor soils and a lack of vegetation cover [ 73 ]. With the similar natural endowment condition, Africa is also rich in mineral resources but short of water resources, facing problems in the areas of water environmental protection and water supply security [ 47 , 78 , 79 ]. By contrast, Southeast Asia, with abundant water, forest, and mineral resources, has the most notable natural resource endowment [ 73 ].…”

Assessment of coastal sustainable development along the maritime silk road using an integrated natural-economic-social (NES) ecosystem

“…The Maritime Silk Road (MSR) is a commercial maritime route that aims to develop economic and cultural linkages between Southeast Asia, Oceania, the Indian Ocean, and East Africa [ 6 , 7 ]. It passes through the coastal zones of a large number of countries and involves a variety of climatic zones such as subtropical, tropical, and Mediterranean [ 8 ]. The coastal zones of MSR face several problems such as environmental pollution and ecological degradation caused by industrialization and urbanization, especially the vast majority of countries involved are developing countries and emerging economies [ 9 ].…”