This study presents a new global baseline of mangrove extent for 2010 and has been released as the first output of the Global Mangrove Watch (GMW) initiative. This is the first study to apply a ...globally consistent and automated method for mapping mangroves, identifying a global extent of 137,600 km 2 . The overall accuracy for mangrove extent was 94.0% with a 99% likelihood that the true value is between 93.6–94.5%, using 53,878 accuracy points across 20 sites distributed globally. Using the geographic regions of the Ramsar Convention on Wetlands, Asia has the highest proportion of mangroves with 38.7% of the global total, while Latin America and the Caribbean have 20.3%, Africa has 20.0%, Oceania has 11.9%, North America has 8.4% and the European Overseas Territories have 0.7%. The methodology developed is primarily based on the classification of ALOS PALSAR and Landsat sensor data, where a habitat mask was first generated, within which the classification of mangrove was undertaken using the Extremely Randomized Trees classifier. This new globally consistent baseline will also form the basis of a mangrove monitoring system using JAXA JERS-1 SAR, ALOS PALSAR and ALOS-2 PALSAR-2 radar data to assess mangrove change from 1996 to the present. However, when using the product, users should note that a minimum mapping unit of 1 ha is recommended and that the error increases in regions of disturbance and where narrow strips or smaller fragmented areas of mangroves are present. Artefacts due to cloud cover and the Landsat-7 SLC-off error are also present in some areas, particularly regions of West Africa due to the lack of Landsat-5 data and persistence cloud cover. In the future, consideration will be given to the production of a new global baseline based on 10 m Sentinel-2 composites.
Wetlands have long been drained for human use, thereby strongly affecting greenhouse gas fluxes, flood control, nutrient cycling and biodiversity
. Nevertheless, the global extent of natural wetland ...loss remains remarkably uncertain
. Here, we reconstruct the spatial distribution and timing of wetland loss through conversion to seven human land uses between 1700 and 2020, by combining national and subnational records of drainage and conversion with land-use maps and simulated wetland extents. We estimate that 3.4 million km
(confidence interval 2.9-3.8) of inland wetlands have been lost since 1700, primarily for conversion to croplands. This net loss of 21% (confidence interval 16-23%) of global wetland area is lower than that suggested previously by extrapolations of data disproportionately from high-loss regions. Wetland loss has been concentrated in Europe, the United States and China, and rapidly expanded during the mid-twentieth century. Our reconstruction elucidates the timing and land-use drivers of global wetland losses, providing an improved historical baseline to guide assessment of wetland loss impact on Earth system processes, conservation planning to protect remaining wetlands and prioritization of sites for wetland restoration
.
•We assessed the capacity of 19 wetland types to deliver ecosystem services.•We identified major drivers of land-use change and their impacts on wetlands.•Wetland decision-making may be improved by ...utilizing national ES maps provided by knowledgeable experts.•Stakeholder participation should be considered as the next step to guarantee an effective science-policy interface.
Wetlands are among the most valuable ecosystems in the world due to their delivery of ecosystem services (ES), but they are particularly vulnerable to drivers of land-use change. However, little is known about how different wetlands respond to drivers of land-use change and how that impacts their delivery of ES. After extreme floods hit Colombia in 2010–2011, negative impacts from these storms heightened the interest of Colombian policy-makers in understanding and recognizing the importance of wetlands. Here, we present a map with 19 wetland types for Colombia and assess the ES that these wetlands deliver and how those ES are impacted by drivers of land-use change. We based our spatial analysis on the Corine Land Cover data for Colombia and combined that with spatial indices derived from knowledgeable experts using the matrix approach and participatory mapping (PGIS). The most vulnerable wetland types identified were floodplain forests, riparian wetlands, freshwater lakes and rivers. The region of Magdalena-Cauca has been identified as the most vulnerable to the impacts of land-use change, until 2025. We discuss our results in light of the current Colombian policy-debate which concerns the designation of wetlands as strategic ecosystems. This designation implies necessary restrictions or prohibition of harmful activities in wetlands, principally mining and industrial agriculture.
We review the conservation issues facing migratory shorebird populations that breed in temperate regions and use wetlands in the non‐breeding season. Shorebirds are excellent model organisms for ...understanding ecological, behavioural and evolutionary processes and are often used as indicators of wetland health. A global team of experienced shorebird researchers identified 45 issues facing these shorebird populations, and divided them into three categories (natural, current anthropogenic and future issues). The natural issues included megatsunamis, volcanoes and regional climate changes, while current anthropogenic threats encompassed agricultural intensification, conversion of tidal flats and coastal wetlands by human infrastructure developments and eutrophication of coastal systems. Possible future threats to shorebirds include microplastics, new means of recreation and infectious diseases. We suggest that this review process be broadened to other taxa to aid the identification and ranking of current and future conservation actions.
Internal migration has played a significant role in shifting the population from rural to urban areas worldwide. In Bhutan, rural depopulation is mostly concentrated in the country's eastern and some ...central parts, and is changing the rural landscape, economy, and society. In discussing rural population change, the term Gungtong is widely used in the Bhutanese media and public discourses. The literal translation of Gungtong is an empty registered house. However, Gungtong is often interpreted differently in the absence of a clear legal definition. Therefore, the primary objective of this article is to explore the various interpretations of the term Gungtong and understand its meaning. To explore this, 40 semistructured interviews with Bhutanese officials and rural residents were conducted. The study highlights that the Gungtong data gathered annually by the government are based on the administrative complexity of rural taxation policy rather than the actual departure of people from rural areas and empty houses. However, the conversation around Gungtong relates to the globally recognized issue of rural depopulation. Thus, there are discrepancies within the official dataset and between the dataset and the general understanding of the issues and implications of Gungtong. Developing a clear understanding of the term Gungtong and restructuring the data collection of empty houses will help answer some critical questions on the impact of rural depopulation in farming and the rural economy, considering Bhutan's aspiration to be food self-sufficient.
The conservation and sustainable use of marine resources is a highlighted goal on a growing number of national and international policy agendas. Unfortunately, efforts to assess progress, as well as ...to strategically plan and prioritize new marine conservation measures, have been hampered by the lack of a detailed, comprehensive biogeographic system to classify the oceans. Here we report on a new global system for coastal and shelf areas: the Marine Ecoregions of the World, or MEOW, a nested system of 12 realms, 62 provinces, and 232 ecoregions. This system provides considerably better spatial resolution than earlier global systems, yet it preserves many common elements and can be cross-referenced to many regional biogeographic classifications. The designation of terrestrial ecoregions has revolutionized priority setting and planning for terrestrial conservation; we anticipate similar benefits from the use of a coherent and credible marine system.
Given that increasing migration has been addressed as a major consequence of climate change, a growing number of scholars suggest that the planned relocation of people or Government Resettlement ...Projects (GRPs) should be included in climate change adaptation. This paper reviews the status of climate change and environmentally induced migration in China, and then presents an empirical case study in Shangnan County in northwest China, where a specific GRP called the ‘Massive Southern Shaanxi Migration Program’ (MSSMP) has been initiated in response to climate change-related impacts. The results showed that the MSSMP helped local residents to adapt better climate change by reducing exposures to risk, enabling mobility, providing financial incentives, raising living standards, and improving emotional status. Furthermore, the MSSMP added additional benefits for migrants compared with traditional GRPs by respecting voluntary participation, preparing for future risks, and reducing social isolation via a short relocation distance. However, GRPs could also be seen as a maladaptation to climate change because they disproportionately increase the burden on the most vulnerable community members, such as those who are financially disadvantaged, new migrants, and people who are left behind. The paper further suggests that the GRPs should be designed by involving multiple adaptation strategies as supplements for GRPs, and broadening the political schemes to consider the special needs of vulnerable groups. This study contributes to an understanding of the roles of GRPs in sustainable climate change adaptation, thereby facilitating the design, organization, and implication of future similar programs.
Summary
The National Agricultural Productivity & Reconciliation Ecology Centre (NAPREC) held its inaugural conference in Deniliquin in the southern Murray–Darling Basin, NSW, Australia, 4–5 October ...2017, and attracted an engaged group of farmers, researchers, industry and government representatives. The theme of the conference was ‘Positive Partnerships for Pathways to Sustainable Agriculture and Biodiversity’. It explored the application of Reconciliation Ecology and the value of the human elements of natural resource management within the context of the southern Murray–Darling Basin.
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