Coastal vegetation planting projects for tsunami disaster mitigation: effectiveness evaluation of new establishments

Abstract

Coastal vegetation acts as a natural barrier against extreme natural and anthropogenic activities, protecting infrastructure and human lives. Establishment of hard infrastructure for tsunami protection is not feasible in developing countries due to its cost-intensive nature. Coastal vegetation can therefore be a feasible alternative for tsunami and general coastal protection in developing countries. This study investigates the effectiveness of current coastal vegetation projects and reports a pilot-scale vegetation project, which provides insights into the management and sustainability of such projects. Thirty-seven establishments of coastal vegetation for tsunami protection were identified for the study from Hambantota to Colombo along the southern coast in Sri Lanka. Evaluation was carried out to assess whether the coastal vegetation establishments fulfilled the planning objectives, such as vegetation alignment to tsunami direction, tree density and tree species, and whether monoculture or mixed species are grown. The study also assessed continuous maintenance and awareness about coastal vegetation, community participation and long-term institutional support from government, nongovernment groups, academic institutions, and other institutions within an integrated framework. Approximately 50% of the sites were found to be effective in terms of fulfilling the above requirements and had reasonable protection against future tsunami-type events. Continuous maintenance is ensured only for 35% of sites with community participation. The survey also revealed the importance of adopting scientific and nonscientific methods of vegetation establishment and selecting appropriate species and structure of vegetation strips for tsunami protection. It is expected that this will lead to the development of coastal vegetation guidelines for local authorities.

A study of urban heat island of Banda Aceh City, Indonesia based on land use/cover changes and land surface temperature

“…This aims to encourage growth in the region so that it can reduce growth trends to the city center. The development of green open space in the northern part of the city, especially in coastal areas, is not to encourage growth, but to minimize the impact tsunamis that may recur (Tanaka et al, 2011;Tanaka, 2009).…”

Peer Review #1 of "Genetic diversity and its conservation implications of Vitex rotundifolia (Lamiaceae) populations in East Asia (v0.1)"

“…Tajima's D test and Fu's Fs test in the ARLEQUIN 3.5 software, with 1000 permutations, were applied to detect historical demographic range expansions of V. rotundifolia and V. trifolia (Excoffier & Lischer, 2010). The significance of the D value is associated with bottlenecks, selective effects, population expansion, or heterogeneity of mutation rates (Tanaka et al, 2011).…”

Green infrastructure: innovative use of indigenous ecosystems and knowledge

“…During the last decade tsunamis have had strong impacts in a number of countries. Several articles in Landscape and Ecological Engineering have reported the effects of coastal vegetation on disaster reduction (Chang et al 2006;Rodriguez et al 2016;Tanaka 2009;Tanaka et al 2007Tanaka et al , 2011Tanaka and Ogino 2017;Tanaka and Onai 2017). For example, coastal vegetation mitigated the impact of a tsunami on coastal villages in Chile (Rodriguez et al 2016).…”

“…Mangroves and other trees have been found to be especially effective in providing protection from tsunami damage due to their complex aerial root structure (Tanaka et al 2007), whereas the construction of hard infrastructure for tsunami protection is not feasible in many developing countries due to its high cost. The application of coastal vegetation can therefore be a feasible alternative for tsunami and general coastal protection in developing countries (Tanaka et al 2011). Chang et al (2006) emphasizes that importance of designs that consider the ecology and culture of the region in question for recovery after disasters.…”