World Bank Blogs IBRD and IDA: Working for a World Free of Poverty. en New evidence on coastal wetlands as carbon sinks <p>In the corridors of COP 16 in Cancun last December, `blue carbon’ was being discussed in the context of Reduced Emissions from Deforestation and Forest Degradation (REDD+). The notion that wetlands and near-shore marine habitats constitute significant but largely unaccounted for natural sinks of atmospheric CO<sub>2</sub> was just beginning to surface. Since then, there has been a surge in interest in Coastal Carbon Sinks, as evidence begins to mount on their ability to suck up CO<sub>2</sub> and store it in their biomass and in deep sub-surface soil layers.&nbsp;A recently published study in <a href="">Nature GeoScience</a> cites evidence from field measurements that mangroves in Indonesia can actually store carbon at four times the rate of their terrestrial forest counterparts.</p> <p><img src="" alt="" align="right" border="1" height="200" hspace="2" vspace="2" width="300">In contrast to terrestrial forests, mangroves and other wetlands store most of the carbon below ground, in a rich organic soil layer, which can run several meters deep.&nbsp;When this soil layer is disturbed—as happens when wetlands are drained or converted for other land use—huge amounts of carbon are released into the atmosphere in the form of CO<sub>2</sub>, and centuries or millennia of accumulated carbon can be emitted over the course of a few decades.</p> <p>The extent of these emissions in estuaries and deltas, is highlighted in a detailed World Bank technical report. The preliminary findings of the report were summarized for decision-makers in a brief issued last December at the COP 16. The <a href="">technical report</a>, <span>Mitigating Climate Change through Restoration and Management of Coastal Wetlands and Near-shore Marine Ecosystems</span>: Challenges and Opportunities<em>, </em>is available on line and is being <a href=",,contentMDK:22883999%7EpagePK:34370%7EpiPK:34424%7EtheSitePK:4607,00.html">launched</a> today in Indonesia at a <a href=";tx_cal_controller%5bview%5d=event&amp;tx_cal_controller%5btype%5d=tx_cal_phpicalendar&amp;tx_cal_controller%5buid%5d=18&amp;tx_cal_c">Workshop on Tropical Wetland Ecosystems of Indonesia</a>,in Bali.<!--break--></p> <p>The report estimates that, within the major deltas and estuaries subject to drainage which were reviewed for this study, many have experienced losses of close to 1 billion tons of CO<sub>2&nbsp;</sub>(more than twice the annual emissions of Mexico), since large-scale alterations to their hydrology first began about 100 years ago. Mega emitters include the Mekong delta in Vietnam, the Wash-Humber delta in the UK, the Changjiang delta in China, and the Sacramento – San Joaquin delta in the U.S.&nbsp;While the horse is already out of the barn for these heavily populated and developed coastal scapes, it is not too late to restore portions of these vital carbon stores&nbsp;(see for example, the work of <a href="">Restore America’s Estuaries</a>), and to prevent other deltas as well as remaining stands of mangrove forests from going down the same path.</p> <p>But time is running out. As this and other reports warn, coastal wetlands are being lost at an alarming rate—and the pressure is greatest in the tropics.&nbsp;Coastal wetlands are succumbing to urbanization, agriculture, aquaculture, and to impacts from climate change. It is not clear whether mangroves can keep pace with sea level rise, where hardened coastlines block their landward retreat. </p> <p><img src="" alt="" align="left" border="1" height="285" hspace="2" vspace="2" width="190">This race against time, however, is fueling some good basic science and economic analysis on how to translate the carbon sequestration services of coastal wetlands and nearshore marine environments into revenue streams, creating incentives for local governments and communities to protect them. Geochemists and ecologists are struggling to wrap their heads around the complex physics and chemistry of carbon flux to come up with the metrics required for Monitoring, Verification and Reporting (MRV) of carbon emissions reduction. <a href="">Economists</a> are already calculating the value of these services on the Voluntary Carbon Market, with potential links to trade under an expanded REDD+ market</p> <p>In the World Bank, we are beginning to explore alternative livelihood opportunities related to mangrove conservation and rehabilitation linked to REDD+ in coastal communities in Indonesia and other parts of Southeast Asia, where mangrove forests are the richest, and most under threat. National programs for community-based coastal resources management are likely to offer the best opportunities for piloting and scaling up such an approach. The next phase of <a href="">COREMAP</a> (The Coral Reef Rehabilitation and Management Program in Indonesia), which is expected to focus on capturing value from coastal ecosystem services, may just be the place to start.</p> Mon, 11 Apr 2011 09:38:42 -0400 Marea E. Hatziolos The buzz around blue carbon <p><img height="329" alt="Photo credit: J. Tamelander" hspace="3" width="185" align="left" vspace="3" border="1" src="/files/climatechange/reef1.jpg" />The delegates and observers at the COP16 in <a href="">Cancun</a> are getting an earful about <a href="">Blue Carbon</a>&mdash;shorthand for atmospheric carbon sequestered in the earth&rsquo;s coastal and nearshore environments. <a href="">Oceans Day</a><span> at Cancun will feature a session on Blue Carbon, and <a href="">briefs</a>, and <a href="">blogs</a> by ocean advocates are circulating on the net and at side events.&nbsp;The reason for the buzz is that coastal wetlands, including tidal salt marshes, estuaries and river deltas, mangroves and sea grass beds are highly efficient at taking up CO<sub>2</sub> from the atmosphere and converting it into organic material&mdash;then storing it in the soil. In fact, the root systems and sediment layers which build up as this organic material is generated, broken down and deposited, are up to ten times more rich in carbon than the biomass above the surface.</span></p> <p>&nbsp;</p> <p>This makes coastal wetlands even better at sequestering carbon than tropical forests. And, unlike their counterparts on land whose net growth peaks when the forest matures, wetland vegetation continues to grow and sequester carbon in the soil as long as sediments are deposited and the environment remains healthy. This is why Blue Carbon is being brought into the international dialogue on carbon emission offsets and the domain of <a href="">REDD+</a> eligible activities. A <a href=";pid=sites&amp;srcid=ZGVmYXVsdGRvbWFpbnxibHVlY2xpbWF0ZXNvbHV0aW9uc3xneDo2YmVjNTdjYjkxMjQ0NTM2&amp;pli=1">statement</a>, signed by 55 marine and environmental stakeholders from 19 countries has been presented to the COP for action.</p> <!--break--> <p>&nbsp;</p> <p>Like peat lands, tidal salt marshes and estuaries can turn from natural sinks to net emitters of greenhouse gasses when they are drained, burned or converted for agriculture, and the soil becomes exposed to air. Mangroves wetlands that are starved of sediment and freshwaters flows through damming of rivers, or converted into shrimp ponds or paddy or beachfront property for five star hotels no longer store carbon. Instead they emit methane, a GHG four times as potent as carbon dioxide, and highly explosive. Less than two weeks ago, a luxury hotel built on top of a mangrove wetlands not far from the where the COP 16 is deliberating in Cancun, suffered a massive explosion and loss of life.</p> <p>&nbsp;</p> <p>Across the Ocean and several continents away in the Bay of Bengal, mangroves play another, more vital role. Battered by cyclones and storm surge, Bangladesh invested in shoring up its exposed coastline through a massive mangrove aforestation program. This proved to be providential. When Super Cyclone Sidr stuck in 2007&mdash;the strongest named cyclone on record in the Bay of Bengal&mdash;the loss of life was around 4-5,000 people. One year later, in Myanmar, Cyclone Nargis whipped across the Ayerwaddy Delta at similar wind speeds, but without the native mangrove forests to act as a shield&mdash;these having been cleared over decades to make room for rice paddy&mdash;over 140,000 people lost their lives in the storm surge.</p> <p>&nbsp;</p> <p>Seagrass beds, which are often found adjacent to mangroves in sheltered bays along warm water coasts, also store large amounts of carbon in their root systems and in the soil they bind. This is in addition to stabilizing sediment and providing food for sea turtles, manatees and other important herbivores at the base of the food chain. So, besides stripping CO<sub>2</sub> from the atmosphere, coastal wetlands provide a myriad of co-benefits to society that need to be recognized, <a href=",,contentMDK:22746592~pagePK:64257043~piPK:437376~theSitePK:4607,00.html">valued</a> and accounted for. While protection of these natural assets should be the first order of business, restoring degraded wetlands can pay huge dividends in terms of recovering natural carbon sinks, reducing emissions and building resilience into vulnerable coastal communities.</p> Sun, 05 Dec 2010 17:49:22 -0500 Marea E. Hatziolos