Editing IPCC:AR6/WGII/Chapter-2 (section)

=== 2.6.5 Adaptation in Practice: Case Studies and Lessons Learned ===

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Adaptation plans for biodiversity and EbA have been adopted in many places and on different scales, but it is difficult to get a systematic overview of adaptation in practice. We have therefore reviewed a series of contrasting case studies to illustrate some of the key issues. There is a pressing need for more thorough monitoring and evaluation of adaptation to assess effectiveness. Climate change adaptation is conceptually difficult to measure, but it is possible to test which techniques work in reducing vulnerability and to monitor their deployment ( [[#Morecroft--2019|Morecroft et al., 2019]] ).

Adaptation can take place on a range of scales, with specific projects nested within overarching national strategies. Small-scale projects can be adaptation-focused, but on the larger scale, adaptation is often integrated with wider objectives. Within an urban or peri-urban context, the benefits of natural and semi-natural areas for health and well-being help to justify support for EbA. Economic well-being is also an important factor in many cases whether, as in Durban, South Africa ( [[#2.6.5.7|Section 2.6.5.7]] ), it provides new job opportunities or, as in the Andes ( [[#2.6.5.4|Section 2.6.5.4]] ), it supports long-established agricultural practices. Action on the ground often depends on factors on a range of scales, for example, a local plan, a national strategy and international funding. In Durban, partnerships between local communities, local authorities and the academic community were essential, together with an international context. Nevertheless, there are examples of communities using traditional or local knowledge (LK) to adapt to changing circumstances, with little or no external input, ( [[#2.6.5.4|Section 2.6.5.4]] ); Their scope for adaptation is, however, often limited by factors beyond their direct control.

Specific interventions to protect species from climate change, such as the case of African penguins in South Africa ( [[#2.6.5|Section 2.6.5.5]] ) and threatened plant species in the Tasmanian Wilderness World Heritage Area ( [[#2.6.5.8|Section 2.6.5.8]] ), are rare. However, in countries where nature reserves are actively managed or where ecosystem restoration projects are progressing, local practitioners may use their knowledge to adapt to weather conditions and their associated effects (e.g., fire and water shortages). This is good practice, but it may not be sufficient to address the likely future changes in climate ( [[#Duffield--2021|Duffield et al., 2021]] ). Training and resources to support conservation practitioners are becoming available. Examples include the Climate Change Adaptation Manual in England, UK ( [[#2.6.5.2|Section 2.6.5.2]] ), and The Alliance for Freshwater Life ( https://allianceforfreshwaterlife.org ) which provides expertise for the sustainable management of freshwater biodiversity ( [[#Darwall--2018|Darwall et al., 2018]] ).

Adaptation is widely recognised as important for national conservation policies and is being considered in a variety of countries ( [[#2.6.5.2|Section 2.6.5.2]] , 2.6.5.3). Adaptation in this strategic context includes decisions about the selection and objectives for protected areas, for example, identifying places which can act as refugia. It can also mean recognising where protected areas remain important but will support a changing range of species and ecosystems. This is important for directing resources effectively and ensuring that the management of the sites remains appropriate. There are, however, often major uncertainties, and the extent to which there will be a need for more radical measures will depend on the success of reducing GHG emissions globally. A global rise of 1.5°C–2°C would require relatively incremental adjustments to conservation management in many parts of the world, but a 3°C–4°C rise would require radical, transformational changes to preserve many species and maintain ecosystem services ( [[#Morecroft--2012|Morecroft et al., 2012]] ).

Whilst adaptation strategies for conservation are relatively common, at least on an outline level, their implementation is slow in most places. This may partly reflect a lack of resources for conservation in many parts of the world; however, another barrier is that people often value protected sites in their present form. Actions which might jeopardise this are inevitably a last resort. Initiatives to engage wider communities in discussions are likely to be essential in gaining support for such changing approaches.

EbA and adaptation for biodiversity are intrinsically linked and the largest-scale interventions for adaptation in ecosystems have tended to bring together both elements. For example, adaptation to reduce the risk of flooding by habitat creation and using natural processes ( [[#2.6.5.2|Section 2.6.5.2]] , Cross-Chapter Box SLR in Chapter 3), such as re-naturalising straightened river systems or creating wetlands for water storage, offers the potential to meet multiple objectives and has increased the overall funding available for ecosystem restoration.

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==== 2.6.5.1 Case Study: Assisted Colonisation/Managed Relocation in Practice ====

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Scale: Global

Issue: Helping species move in order to track shifting climate space

Managed relocation (assisted migration and colonisation) is the movement of species, populations or genotypes to places outside the areas of their historical distribution ( [[#Hoegh-Guldberg--2008|Hoegh-Guldberg et al., 2008]] ), and it may be an option where they are not able to disperse and colonise naturally. It requires careful consideration of scientific, ethical, economic and legal issues between the object of relocation and the receiving ecosystem ( [[#Hoegh-Guldberg--2008|Hoegh-Guldberg et al., 2008]] ; [[#Richardson--2009|Richardson et al., 2009]] ; [[#Schwartz--2012|Schwartz et al., 2012]] ).

Individual cases show that assisted migration can be successful. Anich and Ward (2017) extended the geographic breeding range of a rare bird, Kirtland’s warbler, ''Setophaga kirtlandii'' , by 225 km by using song playbacks to attract migrating individuals. Wadgymar (2015) successfully transplanted an annual legume, ''Chamaecrista fasciculata'' , to sites beyond its current poleward range limit, while Liu (2012) found that all but one of 20 orchid species survived when transplanted to higher elevations than their current range limits. After introducing two British butterfly species to sites ∼ 65 and ∼ 35 km beyond their poleward range margins, Willis (2009) observed that both of these populations grew, expanded their ranges and survived for at least the 8 year span of the study.

Butterflies have been favoured subjects for assisted migration in response to regional climate warming, since they are easy to move and their range dynamics have been extensively studied. The Chequered Skipper, ''Carterocephalus palaemon'' , became locally extinct in England in the 1970s, in an area not close to either the species’ poleward or equatorial range limits. Nonetheless, Maes (2019) considers climate a crucial parameter for reintroduction, using SDMs for both choosing the source population in Belgium and introduction site.

The success of assisted migration for conservation purposes has been variable. [[#Bellis--2019|Bellis et al. (2019)]] identified 56 successes and 33 failures among 107 translocations of insects undertaken explicitly for conservation purposes. They concluded that failure was most strongly associated with the low numbers of individuals being released. Another potential source of failure is local adaptation: there is ''good evidence'' that adaptive differences among potential source populations can be important. For example, the transplants of ''Chamaecrista fasciculata'' were more successful when sourced from the most poleward existing sites, while individuals from more equatorial habitats performed poorly even when artificially warmed ( [[#Wadgymar--2015|Wadgymar et al., 2015]] ).

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==== 2.6.5.2 Case Study: Adaptation for Conservation and Natural Flood Management in England, UK ====

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Scale: National

Issue: National approach to adaptation in the natural environment

Threats to biodiversity from climate change in England include range retractions of cold-adapted species and the effects of more frequent extreme weather events such as drought. These threats are exacerbated by land use and management, for example, fragmenting habitats, draining land and straightening rivers. There are also risks to people, which are exacerbated by environmental factors, including flooding and over-heating in urban areas. The National Adaptation Programme provides a broad policy framework for England and includes a chapter on the natural environment. There are also adaptation plans produced by public bodies such as Natural England and the UK Environment Agency, with a wide range of responsibilities including flood defence. The principles of adaptation to climate change are well established in the UK conservation community and resources are available. Natural England has published a Climate Change Adaptation Manual jointly with the Royal Society for the Protection of Birds (a major conservation NGO) ( [[#Natural%20England%20and%20RSPB--2020|Natural England and RSPB, 2020]] ) and a spatial mapping tool for vulnerability to climate change ( [[#Taylor--2014|Taylor et al., 2014]] ).

Duffield et al. (2021) found that awareness of the need for adaptation was common amongst nature reserve managers and that they were implementing actions that might build resilience to climate change, such as restoring ecosystem processes and reducing habitat fragmentation. There was recognition that it will be necessary to change the management objectives of protected sites to adjust to changing circumstances, but little implementation of such changes. The main example of managing change was at the coast where the SLR is causing transitions from terrestrial and freshwater systems to coastal and marine ones.

A range of EbA approaches are starting to contribute to adaptation in England, but the best-developed is Natural Flood Management (NFM): restoring natural processes and natural habitats to reduce flood risk ( [[#Wingfield--2019|Wingfield et al., 2019]] ). Over the last decade, a series of NFM projects have been established in local areas. The Environment Agency collated the evidence base for NFM ( [[#Burgess-Gamble--2021|Burgess-Gamble et al., 2021]] ) and was able to draw on 65 case studies ( [[#Ngai--2017|Ngai et al., 2017]] ) covering the management of rivers and floodplains, woodlands, runoff, and coasts and estuaries.

NFM includes a broad range of techniques, some of which deliver real benefits for biodiversity and allow natural ecological processes to become re-established. Others, such as creating ‘woody debris dams’—barriers artificially constructed from tree trunks and branches in watercourses to slow the flow of water— have fewer benefits, although they may be good for some species. [[#Dadson--2017|Dadson et al. (2017)]] concluded that ‘the hazard associated with small floods in small catchments may be significantly reduced’ by NFM techniques. However, they noted that the most extreme flood events may overwhelm any risk management measures, and failed to find clear evidence of NFM reducing flood risk downstream in large catchments.

Challenges in deploying large-scale NFM remain, which partly reflects the length of time necessary to demonstrate the effectiveness of pilot studies and build confidence; building stakeholder support is important ( [[#Huq--2017|Huq et al., 2017]] ). There are now a number of examples of where collaborative initiatives between local communities, landowners and government agencies have been successful in establishing effective NFM schemes ( [[#Short--2019|Short et al., 2019]] ).

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==== 2.6.5.3 Case Study: Protected Area Planning in Response to Climate Change in Thailand ====

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Scale: National

Issue: Protected area network planning

Many countries in the Association of Southeast Asian Nations (ASEAN) are expanding protected area networks to meet the Aichi Target 11 of at least 17% of terrestrial area protected, and it is important to take the effects of climate change into account. Existing protected areas in Thailand cover approximately 21% of the land area and it is one of the few tropical countries that has achieved the Aichi Target 11. Most protected areas in Thailand were established on an ad hoc basis to protect remaining forest cover and, as a result, they do not represent diverse habitats and their associated species ( [[#Chutipong--2014|Chutipong et al., 2014]] ; [[#Tantipisanuh--2016|Tantipisanuh, 2016]] ) so they may not be resilient to the interacting impacts of future land use and climate change ( [[#Klorvuttimontara--2011|Klorvuttimontara et al., 2011]] ; [[#Trisurat--2018|Trisurat, 2018]] ).

Recent research conducted in northern Thailand indicated that the existing protected areas (31% of the regional area) cannot secure the viability of many medium-sized and large mammals. The climate space of most species will shift substantially, bringing a risk of extinction. Results, based on a spatial distribution model and network flow, determined there was a need for expansion areas of 5,200 km 2 in size, or 3% of the region, to substantially minimise the high level of risk and increase the average coping capacity of the protection of suitable habitats from 82%—the current plan—to 90%. These results were adopted by Thailand’s Department of National Parks, Wildlife and Plant Conservation, and included in the National Wildlife Administration and Conservation Plan for 2021–2031.

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==== 2.6.5.4 Case Study: Effects of Climate Change on Tropical High Andean Social Ecological Systems ====

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Scale: Regional

Issue: Complex ramifications of glacial retreat on vegetation, animals, herders and urban populations

Accelerated warming is shrinking tropical glaciers at rates unseen since the middle of the Little Ice Age ( [[#Rabatel--2013|Rabatel et al., 2013]] ; [[#Zemp--2015|Zemp et al., 2015]] ). Climate-driven upwards migration of species, associated with warming and glacier retreat, has modified species distribution and richness and community composition along the Andes altitudinal gradient ( [[#Seimon--2017|Seimon et al., 2017]] ; [[#Carilla--2018|Carilla et al., 2018]] ; [[#Zimmer--2018|Zimmer et al., 2018]] ; [[#Moret--2019|Moret et al., 2019]] ). Climate-driven glacier retreat alters hydrological regimes, directly impacting Andean pastoralists ( [[#López-i-Gelats--2016|López-i-Gelats et al., 2016]] ; [[#Postigo--2020|Postigo, 2020]] ; [[#Thompson--2021|Thompson et al., 2021]] ) and the provision of water to lowland regions ( [[#Vuille--2018|Vuille et al., 2018]] ; [[#Hock--2019|Hock et al., 2019]] ; [[#Orlove--2019|Orlove et al., 2019]] ; [[#Rasul--2019|Rasul and Molden, 2019]] ). The drying of wetlands has modified alpine plant communities, which are relevant for storing carbon, regulating water and providing food for local livestock; this has led to negative impacts on herders’ livelihoods ( [[#Dangles--2017|Dangles et al., 2017]] ; [[#Polk--2017|Polk et al., 2017]] ; [[#Postigo--2020|Postigo, 2020]] ) and affecting the wild vicuña and the domesticated alpaca and llama. The wool from Vicuña ( ''Vicugna vicugna'' ) and alpaca ( ''V. pacos'' ) is an important source of income for indigenous communities and the llama ( ''Lama glama'' ) is their main source of meat. Vicuña are adjusting their feeding behaviour and spatial distribution as vegetation migrates upwards ( [[#Reider--2020|Reider and Schmidt, 2020]] ), causing them to roam outside protected areas and become vulnerable to illegal poaching.

Andean herders have responded to the drying of grasslands by increasing livestock mobility, accessing new grazing areas through kinship and leases, creating and expanding wetlands through building long irrigation canals (several kilometres in length), limiting the allocation of wetlands to new households and sometimes cultivating grasses ( [[#Postigo--2013|Postigo, 2013]] ; [[#López-i-Gelats--2015|López-i-Gelats et al., 2015]] ; [[#Postigo--2020|Postigo, 2020]] ). These adaptive responses to regional climate change are enabled by deeply embedded indigenous institutions that have traditionally governed Andean pastoralists, but they have become severely compromised by national socioeconomic pressures ( [[#Valdivia--2010|Valdivia et al., 2010]] ; [[#Postigo--2019|Postigo, 2019]] ; [[#Postigo--2020|Postigo, 2020]] ). For instance, the quality of water and local pastoralists’ access to it and control of it have declined, due to new mining concessions granted in the headwaters of Andean watersheds ( [[#Bebbington--2009|Bebbington and Bury, 2009]] ) and the diversion of water to areas of lowland coastal desert for agricultural irrigation ( [[#Mark--2017|Mark et al., 2017]] ).

Glacier mass and runoff in the Tropics are projected to diminish by &gt;70% and &gt;10%, respectively, by 2100, under mean of RCP2.6, 4.5 and 8.5 ( [[#Huss--2018|Huss and Hock, 2018]] ; [[#Hock--2019|Hock et al., 2019]] ). In Peru, montane ice-field meltwater provides 80% of the water resources for the arid coast where half the population lives ( [[#Thompson--2021|Thompson et al., 2021]] ). Increasing variability of precipitation has compromised rain-fed agriculture and power generation, particularly in the dry season, exacerbating pressures for new sources of water ( [[#Bradley--2006|Bradley et al., 2006]] ; [[#Bury--2013|Bury et al., 2013]] ; [[#Buytaert--2017|Buytaert et al., 2017]] ). There is therefore a risk of increasing conflicts between adaptation to climate change to benefit human and natural communities in the high Andes and maintaining water provisioning for lowland agricultural and urban areas.

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==== 2.6.5.5 Case Study: Helping African Penguins Adapt to Climate Change ====

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Scale: Regional/local

Issue: Adaptation for a threatened species

The African penguin, ''Spheniscus demersus'' , is the only resident penguin species on mainland Africa. It breeds in a handful of colonies in South Africa and Namibia. In 2017, the penguins of Cape Town’s Boulders Beach colony attracted almost one million visitors, providing 885 jobs and USD 18.9 M in revenue ( [[#Van%20Zyl--2018|Van Zyl and Kinghorn, 2018]] ). Ninety-six percent of the population of this species has been lost since 1900, with a 77% decline in the last two decades ( [[#Sherley--2018|Sherley et al., 2018]] ). By 2019, only 17,700 pairs remained ( [[#Sherley--2020|Sherley et al., 2020]] ). The species is listed as endangered on the IUCN Red List ( [[#Birdlife%20International--2018|Birdlife International, 2018]] ) and if this trajectory persists, the African penguin will become functionally extinct in the near future ( [[#Sherley--2018|Sherley et al., 2018]] ).

Historically, hunting and the collection of eggs and guano were the main threats, but three aspects of climate change now predominate. Firstly, an eastward shift of several hundred kilometres in the distributions of their main prey species, anchovies and sardines, has reduced food availability ( [[#Roy--2007|Roy et al., 2007]] ; [[#Crawford--2011|Crawford et al., 2011]] ). While adult penguins typically forage up to 400 km from their colonies, they are restricted to a ~20-km radius from their colonies during breeding months ( [[#Ludynia--2012|Ludynia et al., 2012]] ; [[#Pichegru--2012|Pichegru et al., 2012]] ). The resulting food shortage at this critical time is compounded by competition with commercial fisheries and environmental fluctuations ( [[#Crawford--2011|Crawford et al., 2011]] ; [[#Pichegru--2012|Pichegru et al., 2012]] ; [[#Sherley--2018|Sherley et al., 2018]] ). This has impacted adults’ survival and their ability to raise high-quality offspring ( [[#Crawford--2006|Crawford et al., 2006]] ; [[#Crawford--2011|Crawford et al., 2011]] ; [[#Sherley--2013|Sherley et al., 2013]] ; [[#Sherley--2014|Sherley et al., 2014]] ).

The increasing frequency and intensity of heat waves recorded in recent decades presents a second threat ( [[#van%20Wilgen--2016|van Wilgen and Wannenburgh, 2016]] ; [[#Van%20Wilgen--2016|Van Wilgen et al., 2016]] ; [[#Mbokodo--2020|Mbokodo et al., 2020]] ). Nests were historically built in insulated guano burrows, but are now frequently sited on open ground ( [[#Kemper--2007|Kemper et al., 2007]] ; [[#Pichegru--2012|Pichegru et al., 2012]] ; [[#Sherley--2012|Sherley et al., 2012]] ). High temperatures frequently expose the birds to severe heat stress, causing adults to abandon their nests and resulting in the mortality of eggs and chicks ( [[#Frost--1976|Frost et al., 1976]] ; [[#Shannon--1999|Shannon and Crawford, 1999]] ; [[#Pichegru--2012|Pichegru et al., 2012]] ). Intensifying storm surges and greater wave heights can cause nest flooding ( [[#Randall--1986|Randall et al., 1986]] ; [[#de%20Villiers--2002|de Villiers, 2002]] ).

The African penguin’s survival in the wild is dependent on the success of adaptation action. Increasing access to food resources is a management priority ( [[#Birdlife%20International--2018|Birdlife International, 2018]] ). One approach is to reduce fishing pressure immediately around breeding colonies. An experiment excluding fishing around colonies since 2008 has demonstrated positive effects ( [[#Pichegru--2010|Pichegru et al., 2010]] ; [[#Pichegru--2012|Pichegru et al., 2012]] ; [[#Sherley--2015|Sherley et al., 2015]] ; [[#Sherley--2018|Sherley et al., 2018]] ; [[#Campbell--2019b|Campbell et al., 2019b]] ). A second approach is to establish breeding colonies closer to their prey. An ongoing translocation initiative aims to entice birds eastwards, to recolonise an extinct breeding colony and potentially establish a new one ( [[#Schwitzer--2013|Schwitzer et al., 2013]] ; [[#Sherley--2014|Sherley et al., 2014]] ; [[#Birdlife%20International--2018|Birdlife International, 2018]] ). Penguin ‘look-alikes’ or decoys, constructed from rubber and concrete, have been placed at the site of the extinct colony, and, along with call play-backs, these give the illusion of an established penguin colony ( [[#Morris--2018|Morris and Hagen, 2018]] ). This approach has not yet proven successful.

To promote on-site adaptation to heat extremes and flooding, initiatives are underway to provide cooler nesting sites that also provide storm protection and are sufficiently above the high-water level ( [[#Birdlife%20International--2018|Birdlife International, 2018]] ; [[#Saving%20Animals%20From%20Extinction--2018|Saving Animals From Extinction, 2018]] ). Artificial nest boxes of various designs and constructed from a range of materials have been explored, in combination with the use of natural vegetation. Some designs have proven successful, increasing breeding success ( [[#Kemper--2007|Kemper et al., 2007]] ; [[#Sherley--2012|Sherley et al., 2012]] ), but the same designs have had less success at other locations ( [[#Pichegru--2013|Pichegru, 2013]] ; [[#Lei--2014|Lei et al., 2014]] ).

Hand-rearing and releasing African penguin chicks, including from eggs, has long proven valuable because moulting parents, being shore-bound, are unable to feed late-hatching chicks. Since 2006, over 7,000 orphaned chicks have been released into the wild as part of the Chick Bolstering Project, with a success rate of 77% ( [[#Schwitzer--2013|Schwitzer et al., 2013]] ; [[#Sherley--2014|Sherley et al., 2014]] ; [[#Klusener--2018|Klusener et al., 2018]] ; [[#SANCCOB--2018|SANCCOB, 2018]] ). A new project at Boulders Beach aims to use real-time weather station data, within-nest temperatures and known thresholds of penguin heat stress as triggers for implementing a Heat Wave Response Plan. Drawing on well-established chick-rearing facilities and a large body of expertise, this includes removing heat-stressed eggs and birds, hand-rearing and/or rehabilitation and release. It is hoped that such birds can be released at the proposed new colony site.

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==== 2.6.5.6 Case Study: Conserving Climate Change Refugia for the Joshua Tree in Joshua Tree National Park, CA, USA ====

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Scale: Local

Issue: Possible extirpation of a plant species from a national park

Joshua Tree National Park conserves 3200 km 2 of the Mojave and Sonoran Desert ecosystems. The climate of the national park is arid, with an average summer temperature of 27.3°C ± 0.7°C and average annual precipitation of 170 ± 80 mm yr -1 in the period 1971–2000 ( [[#Gonzalez--2018|Gonzalez et al., 2018]] ). From 1895 to 2017, the average annual temperature increased at a significant (P &lt; 0.0001) rate of 1.5°C ± 0.1°C per century and the average annual precipitation decreased at a significant (P = 0.0174) rate of -32 ± 12% per century ( [[#Gonzalez--2018|Gonzalez et al., 2018]] ). Anthropogenic climate change accounts for half the magnitude of a 2000–2020 drought in the southwestern USA, the most severe since the 1500s ( [[#Williams--2020|Williams et al., 2020]] ).

The national park was established to protect ecosystems and cultural features unique to the region, particularly the Joshua tree ( ''Yucca brevifolia'' ), a tall, tree-like yucca that provides habitat for birds and other small animals and holds cultural significance. The national park protects the southernmost populations of the Joshua tree. Palaeo-biological data from packrat ( ''Neotoma'' spp.) middens and fossilised dung of the extinct Shasta ground sloth ( ''Nothrotheriops shastensis'' ) show that Joshua trees grew 13,000–22,000 years ago across a wider range, extending as far as 300 km south into what is now México ( [[#Holmgren--2010|Holmgren et al., 2010]] ; [[#Cole--2011|Cole et al., 2011]] ). A major retraction of this range began ~11,700 years ago, coinciding with warming of approximately 4°C, caused by Milankovitch cycles, which marked the end of the Pleistocene and the beginning of the Holocene ( [[#Cole--2011|Cole et al., 2011]] ), suggesting a sensitivity of Joshua trees of 300 km of latitude per 4°C.

Under an emissions scenario that could increase park temperatures by &gt;4°C by 2100, the suitable climate for the Joshua tree could shift northwards and the species become extirpated from the park ( [[#Sweet--2019|Sweet et al., 2019]] ). Plant mortality would increase from drought stress and wildfires, which have been rare or absent in the Mojave, but which invasive grasses have fuelled and may continue to fuel ( [[#Brooks--2006|Brooks and Matchett, 2006]] ; [[#DeFalco--2010|DeFalco et al., 2010]] ; [[#Abatzoglou--2011|Abatzoglou and Kolden, 2011]] ; [[#Hegeman--2014|Hegeman et al., 2014]] ).

The national park had been trying to conserve the species wherever in the park it was found. The future risk of extirpation prompted adaptation of conservation efforts to focus on protecting potential refugia, where suitable conditions may persist for the species into the future ( [[#Barrows--2020|Barrows et al., 2020]] ). The national park used spatial analyses of suitable climate to identify potential refugia under all emissions scenarios, except for the highest ( [[#Barrows--2012|Barrows and Murphy-Mariscal, 2012]] ; [[#Sweet--2019|Sweet et al., 2019]] ). The park prioritises the refugia for removal of invasive grasses and fire control ( [[#Barrows--2020|Barrows et al., 2020]] ) and works to restore refugia that have burned in fires, using native plants, including nursery-grown Joshua tree seedlings. The park and its partners are monitoring plant species composition and abundance in the refugia for early warnings of any changes ( [[#Barrows--2014|Barrows et al., 2014]] ).

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==== 2.6.5.7 Case Study: Ecosystem Based Adaptation in Durban, South Africa ====

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Scale: Local

Issue: EbA in a city and surrounding area

Durban was an early pioneer of EbA in a city context, establishing a Municipal Climate Protection Programme (MCPP) in 2004 ( [[#Roberts--2012|Roberts et al., 2012]] ). The city, situated in a global biodiversity hotspot (World Bank, 2016), has a rapidly growing population (approximately 3.5 million) and is highly fragmented ( [[#Roberts--2013|Roberts et al., 2013]] ). High levels of development, particularly in peri-urban areas, have encroached into natural habitats (World Bank, 2016). Degradation of the natural resource base in this way has direct economic and financial costs, is threatening Durban’s long-term sustainability and is exacerbated by climate change (World Bank, 2016; [[#eThekwini%20Municipality--2020|eThekwini Municipality, 2020]] ). The impacts of climate change are anticipated to increase unless appropriate mitigation and adaptation interventions are prioritised ( [[#eThekwini%20Municipality--2020|eThekwini Municipality, 2020]] ). High rates of poverty, unemployment and health problems have pushed Durban to explore a climate change adaptation work stream within its MCPP ( [[#Roberts--2013|Roberts et al., 2013]] ; [[#Roberts--2020b|Roberts et al., 2020b]] ).

A single approach to adaptation is likely to be insufficient ( [[#Archer--2014|Archer et al., 2014]] ), and community-based adaptation should be integrated as part of a package of tools applied at the city level. Durban’s climate change adaptation work stream is composed of three separate components: municipal adaptation (adaptation activities linked to the key functions of local government), community-based adaptation (CbA, focused on improving the adaptive capacity of local communities), and a series of urban management interventions (addressing specific challenges such as the urban heat island, increased storm-water runoff, water conservation and SLR) ( [[#Roberts--2013|Roberts et al., 2013]] ).

Lessons learnt from Durban’s experience include the importance of meaningful partnerships, long-term financial commitments ( [[#Douwes--2015|Douwes et al., 2015]] ) and significant political and administrative will ( [[#Roberts--2012|Roberts et al., 2012]] ; [[#Roberts--2020b|Roberts et al., 2020b]] ). Securing these requires strong leadership ( [[#Douwes--2015|Douwes et al., 2015]] ), including from local champions ( [[#Archer--2014|Archer et al., 2014]] ), even when EbA is considered cost-effective ( [[#Roberts--2012|Roberts et al., 2012]] ). Projects for the restoration of natural habitats are seen as an ideal tool, as they combine mitigation outcomes with an increased adaptation capacity, not only reducing the vulnerability of ecosystems and communities ( [[#Douwes--2016|Douwes et al., 2016]] ) but creating economic opportunities. These include direct job creation ( [[#Diederichs--2016|Diederichs and Roberts, 2016]] ; [[#Douwes--2016|Douwes and Buthelezi, 2016]] ) with various spin-offs such as better education for schoolchildren ( [[#Douwes--2015|Douwes et al., 2015]] ). Indirect benefits, including better water quality and reduced flooding, are generated as a result of improved ecosystem service delivery ( [[#Douwes--2016|Douwes and Buthelezi, 2016]] ). In areas that are already developed, opportunities for green-roof infrastructure can yield reductions in roof storm-water runoff (by approx.. 60 ml/m 2 /min during a rainfall event), slow the release of water over time and reduce temperatures on roof surfaces ( [[#Roberts--2012|Roberts et al., 2012]] ).

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==== 2.6.5.8 Case Study: Protecting Gondwanan Refugia against Fire in Tasmania, Australia ====

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Scale: Local

Issue: Protection of rare endemic species

The Tasmanian Wilderness World Heritage Area (TWWHA) has a high concentration of ‘palaeo-endemic’ plant species which are restricted to living in cool, wet climates and fire-free environments, but recent wildfires have burnt substantial stands that are unlikely to recover ( [[#Harris--2018b|Harris et al., 2018b]] ; [[#Bowman--2021a|Bowman et al., 2021a]] ). The fires led to government inquiries and a fire-fighting review, which have suggested changes to management as climate change will make such fires more likely in the future ( [[#AFAC--2016|AFAC, 2016]] ; [[#Press--2016|Press, 2016]] ; [[#AFAC--2019|AFAC, 2019]] ).

Most of the TWWHA is managed as a wilderness zone and is currently carried out in a manner that allows natural processes to predominate. The exclusion of fire from stands of fire-sensitive trees such as the pencil pine, ''Athrotaxis cupressoides'' , is part of this management strategy, possible in the past due to the moisture differential and lower flammability of these areas. However, in recent years, the threat posed by extensive and repeated wildfires and increasing awareness that fire risk is likely to increase ( [[#Fox-Hughes--2014|Fox-Hughes et al., 2014]] ; [[#Love--2017|Love et al., 2017]] ; [[#Love--2019|Love et al., 2019]] ) have meant that more direct management intervention has been implemented. There has been a realisation that a ‘hands off’ approach to managing the threat will not be sufficient to protect the palaeo-endemics. Not only is fire-fighting difficult in this remote wilderness area, but limited resources mean that fire managers must prioritise where fires will be fought when many fires are threatening towns and lives across the state simultaneously.

After the wildfires in 2016 caused extensive damage ( [[#Bowman--2021a|Bowman et al., 2021a]] ), significant efforts and resources were spent trying to protect the remaining stands of pencil pine during the 2019 fires, using new approaches including the strategic application of long-term fire retardant and the installation of kilometres of sprinkler lines ( [[#AFAC--2019|AFAC, 2019]] ). These approaches are thought to have been effective at halting the fire and protecting high-value vegetation in some situations. Impact reports are currently being finalised to quantify the extent of fire-sensitive vegetation communities that have been affected. However, there is concern that these interventions may have adverse effects on the values of the TWWHA if applied widely, so while research is ongoing, these will only be applied in strategic areas (e.g., fire retardant is not being applied to some areas).

The TWWHA Management Plan (2016) emphasises Aboriginal fire management as an important value of the area, along with Aboriginal knowledge of plants, animals, marine resources and minerals (ochre and rock sources), and the connection with the area as a living and dynamic landscape. Fire management planning aims to protect important sites from fire and ensure that management does not impact Aboriginal cultural values ( [[#DPIPWE--2016|DPIPWE, 2016]] ). Increasingly, there is an acknowledgment that the cessation of traditional fire use has led to changes in vegetation and there are calls to incorporate Aboriginal burning knowledge into the fire management of the TWWHA.

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==== 2.6.5.9 Case Study: Bhojtal Lake, Bhopal, India ====

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Scale: Local

Issue: Protection of water resources and biodiversity

The city of Bhopal, the capital of Madhya Pradesh state in central India, is dependent for its water supply on Bhojtal, a large man-made lake bordering the city ( [[#Everard--2020|Everard et al., 2020]] ). Bhojtal is also an important conservation site, with its wetlands protected under the Ramsar convention and diverse flora and fauna ( [[#WWF--2006|WWF, 2006]] ). It also provides a wide range of other benefits to people, including tourism, recreation, navigation and subsistence and commercial fisheries, supporting the livelihoods of many families ( [[#Verma--2001|Verma, 2001]] ).

Climate change in Bhopal may pose ecological and socioeconomic stresses due to changes in rainfall and weather patterns ( [[#Ministry%20of%20Environment--2019|Ministry of Environment et al., 2019]] ), and exacerbated by a series of problems such as waste-water discharge, illegal digging of bore wells and unsustainable water extraction/exploitation ( [[#Everard--2020|Everard et al., 2020]] ). Ecosystem service provision at Bhojtal was assessed using the Rapid Assessment of Wetland Ecosystem Services (RAWES) approach, including an analysis of the lake’s water quality. Information on the geology, hydrology and catchment ecology of the lake was collected and a baseline biodiversity assessment was conducted.

The Lake Bhopal Conservation and Management Project ( [[#JICA--2007|JICA, 2007]] ) was developed with the following actions:

# Desilting and dredging; deepening and widening of spill channel; prevention of pollution (sewage scheme); management of shoreline and fringe area; improvement and management of water quality
# Soil and water conservation measures using vegetative and engineering structures, particularly at upper ridges of watersheds; construction of small check dams or percolation tanks for recharge purposes in areas marked for ‘drainage line recharge measures’
# Afforestation initiatives

Implementation of these measures with the help of local communities improved the lake’s health. NbS are more resilient adaptation measures towards climate change. Restoration not only reduced water stress but also provides multiple societal benefits in the urban area ( [[#Kabisch--2016|Kabisch et al., 2016]] ).

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==== 2.6.5.10 Case Study: Addressing the Vulnerability of Peat Swamp Forests in Southeast Asia ====

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Scale: Regional

Issue: Protecting peatland biodiversity, carbon and ecosystem services from climate change and land degradation

Peatlands in SEA have undergone extensive logging, drainage and land use conversion that have caused habitat loss for endemic species, i.e., the orangutan ( ''Pongo'' spp.) ( [[#Gregory--2012|Gregory et al., 2012]] ; [[#Struebig--2015|Struebig et al., 2015]] ). Prolonged droughts associated with El Niño ( [[IPCC:Wg2:Chapter:Chapter-4#4.4.3|Section 4.4.3.2]] ) compound the effects of drainage, leading to large recurrent fires ( [[#Langner--2009|Langner and Siegert, 2009]] ; [[#Gaveau--2014|Gaveau et al., 2014]] ; [[#Putra--2019|Putra et al., 2019]] ). Under RCP8.5, it is projected that by the end of this century, the annual rainfall over SEA will decrease significantly (by 30%), and the number of consecutive dry days will increase significantly (by 60%) over Indonesia and Malaysia (Supari et al., 2020). Peat degradation and losses to fire result in high GHG emissions ( [[#Miettinen--2016|Miettinen et al., 2016]] ) as well as haze pollution which is a trans-boundary problem in the region ( [[#Heil--2007|Heil et al., 2007]] ).

Improving the resilience of SEA peatlands to fire and climate change through restoration is extremely difficult and presents many challenges. The Indonesian government has tasked the Badan Restorasi Gambut (Peatland Restoration Agency) to restore peatlands ( [[#Darusman--2021|Darusman et al., 2021]] ; [[#Giesen--2021|Giesen, 2021]] ). Other local initiatives exist, such as fire management programmes and restoration projects ( [[#Puspitaloka--2020|Puspitaloka et al., 2020]] ). Since 2016, the government of Indonesia has re-wetted ~380,000 hectares of degraded peatlands, mainly by blocking canals and flooding, but less than 2000 hectares have been successfully restored to sustaining native plant species common to peat swamp forests ( [[#Giesen--2021|Giesen, 2021]] ). Replanting native trees has had relatively little success ( [[#Lampela--2017|Lampela et al., 2017]] ) because such trees have low tolerance to prolonged inundation and no fire adaptation strategies ( [[#Page--2009|Page et al., 2009]] ; [[#Roucoux--2013|Roucoux et al., 2013]] ; [[#Dohong--2018|Dohong et al., 2018]] ; [[#Cole--2019|Cole et al., 2019]] ; [[#Luom--2020|Luom, 2020]] ; [[#Giesen--2021|Giesen, 2021]] ).

The barriers to successful management are complex, and include the disparity in time frames between ecological restoration and political/socioeconomic needs ( [[#Harrison--2020|Harrison et al., 2020]] ) and an over-focus on fire-fighting rather than fire prevention ( [[#Mishra--2021a|Mishra et al., 2021a]] ). Early protection of peat forests has been highlighted as a more effective management strategy than restoration, not only on islands in SEA but also in areas like Papua New Guinea, which may be targeted for the expansion of estate crop plantations ( [[#Neuzil--1997|Neuzil et al., 1997]] ; [[#Dennis--1999|Dennis, 1999]] ; [[#Anshari--2001|Anshari et al., 2001]] ; [[#Anshari--2004|Anshari et al., 2004]] ; [[#Hooijer--2006|Hooijer et al., 2006]] ; [[#Heil--2007|Heil et al., 2007]] ; [[#Page--2009|Page et al., 2009]] ; [[#Page--2011|Page et al., 2011]] ; [[#Posa--2011|Posa et al., 2011]] ; [[#Miettinen--2012|Miettinen et al., 2012]] ; [[#Wetlands%20International--2012|Wetlands International, 2012]] ; [[#Biagioni--2015|Biagioni et al., 2015]] ; [[#Miettinen--2016|Miettinen et al., 2016]] ; [[#Rieley--2016|Rieley and Page, 2016]] ; [[#Adila--2017|Adila et al., 2017]] ; [[#Cole--2019|Cole et al., 2019]] ; [[#Vetrita--2019|Vetrita and Cochrane, 2019]] ; [[#Harrison--2020|Harrison et al., 2020]] ; [[#Hoyt--2020|Hoyt et al., 2020]] ; [[#Ruwaimana--2020|Ruwaimana et al., 2020]] ; [[#Ward--2020|Ward et al., 2020]] ; [[#Cole--2021|Cole et al., 2021]] ).

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