News category: NWS_SCIENCE

Jonna, a talented environmental engineering student from Stockholm’s esteemed Royal Institute of Technology (KTH), collaborated with Nature-based Solutions Initiative, with expert guidance from Dr. William Thompson and Dr. Ulla Mörtberg, for this key research – as part of the UKRI NERC funded HARP project.

Following several months based in the NbSI in Oxford, Jonna immersed herself in the world of cocoa farming, in the landscapes of Kumasi, Ghana. There, her study explored the potential of shade trees in sustaining cocoa production under changing climatic conditions.

The fieldwork was partly funded through the Swedish scholarship Minor Field Studies provided by The Swedish International Development Cooperation Agency.

The thesis consisted of two parts:

1. To conduct a species distribution model to examine which shade trees used in West African cocoa agroforestry systems would be suitable for future climates;
2. To examine how the microclimate on farms was affected by the diversity of shade trees on the farms.

As part of the fieldwork, Jonna joined up with a team of skilled field assistants from Ghana’s Kwame Nkrumah University of Science and Technology (KNUST). Together, they gathered comprehensive data on microclimatic measurements, farm characteristics, and household surveys. Harnessing technology, they also utilized drones to acquire valuable aerial data.

To comprehensively evaluate microclimate influence, Jonna strategically positioned sensors both above the cocoa canopy and in the ground, to record maximum temperatures during the study period. By comparing temperatures recorded near shade trees versus in open areas, she sought to assess the shade trees’ buffering capacity. The study incorporated three distinct farm structures, which were categorized based on the diversity and density of shade tree species.

Data analysis found farms with a medium/high density of shade trees exhibited a significant buffering of temperature increases, when sensors were placed above the cocoa canopy near a shade tree. However, no significant changes were observed at ground-level. This indicates potential benefits for local farmers of further research of agroforestry solutions, to aid crop resilience against projected temperature rises in West Africa. By integrating shade trees into cocoa farms, farmers can increase resilience to climate change while promoting sustainable and eco-friendly cocoa production practices.

By tapping into the potential of nature-based solutions such as agroforestry, we can build resilient agricultural systems and ensure a thriving cocoa industry for generations to come.

 

 

Related Publication

Cocoa plantations are associated with deforestation in Côte d’Ivoire and Ghana | Nature Food

 

 

 

The production of coffee, one of the world’s most popular beverages, is facing an uncertain future due to climate change.

As the effects of climate change are felt, Vietnam, the second-largest coffee producer globally, is grappling with declining productivity, water shortages, soil degradation, and increased pest and disease prevalence. Looking at possible future solutions, NbSI Masters student Caleb Bram embarked on a mission to explore the synergies and trade-offs between environmental and socio-economic outcomes for coffee agroforestry systems in this crucial region.

Caleb focused his research on agroforestry as a nature-based solution. Agroforestry, the practice of integrating trees and crops, offers a promising solution to the modern agricultural challenge: how can we increase production to meet global demands, whilst also reducing environmental harm and safeguarding farmers’ livelihoods?

Combining crops to tackle climate change  

By studying coffee agroforestry, where coffee is grown under shade, we can unlock the potential to address these critical concerns.

Conducting fieldwork in Vietnam’s Central Highlands, (with support from the University of Oxford, The Tropical Agriculture Association (TAA) and EuroFins Foundation), Caleb compared full-sun coffee monocultures with two shaded coffee agroforestry systems: coffee-pepper intercropping and fruit-based coffee agroforestry. Over eight weeks, he collected data through interdisciplinary research, including surveys, on-farm measurements, and a microclimate study in Vietnam’s Lak district. The goal of this study was to quantify the effects of shaded coffee systems on various environmental, social, and economic indicators.

Key findings of the study showed notable differences between shaded agroforestry and monoculture growing systems:

• Total productivity per unit land area in shaded coffee systems was, on average, higher by 1 tonne per hectare (t ha-1) compared to coffee monocultures.
• Net income per hectare ($ ha-1) in shaded coffee systems were, on average, greater by $1760 compared to coffee monocultures.
• Maximum temperatures experienced by coffee trees were 1.7 degrees celcius lower under shade compared to unshaded conditions.
• Relative humidity under shade was 2.9% higher compared to unshaded conditions.
• On average, above ground carbon storage was higher in shaded coffee systems by 6.5 Megagrams carbon per hectare (Mg C ha-1). i.e., carbon sequestration in shaded coffee systems was, on average, 1.8 times greater than coffee monocultures.

Results unveiled a wealth of benefits provided by shaded coffee systems, in which lie the potential to tackle the effects of climate change on production through this as a nature-based solution. Shaded agroforestry systems not only sequestered significantly more carbon than monocultures, but they also created microclimates that favoured coffee plants during the intense dry season. Shade offered relief with lower air temperatures and higher relative humidity, protecting the delicate coffee plants. Furthermore, the shaded coffee systems demonstrated increased water-use efficiency without sacrificing productivity. This breakthrough suggests the potential to implement significant reductions in irrigation rates while maintaining competitive coffee yields.

Contrary to the perception of trade-offs between environmental and socio-economic benefits, the shaded coffee systems proved to be a win-win solution. Not only were they more productive than monocultures, but they also generated higher profits for farmers. Diversification of the coffee growing system enhanced economic resilience during periods of low coffee prices, as farmers were shielded from volatile market changes. These findings highlight the compatibility of ecological benefits with improved socio-economic performance through nature-based solutions.

This research provided key insights into coffee agroforestry as a nature-based solution that meets the needs of both people and the planet. Insights gained from this study can inform the development of locally relevant and context-specific policies for coffee farmers in the Central Highlands of Vietnam. Additionally, these findings can aid the development of decision-making frameworks for agroforestry, such as the Oxford-led HARP Toolkit.

As the Central Highlands of Vietnam grapples with the challenges of climate change, coffee agroforestry emerges as a beacon of hope. By integrating trees and crops, we can mitigate and adapt to future climates, while simultaneously supporting the local community and economy, and reduce environmental degradation. This research demonstrates a pathway for sustainable coffee farming, emphasizing the importance of balancing ecology and the economy.

 

Paper: “Investigating the synergies and trade-offs between environmental and socio-economic outcomes for coffee agroforestry systems in the Central Highlands of Vietnam.”

With thanks to The Tropical Agriculture Association (TAA) and EuroFins Foundation, who provided grants to facilitate this key research.

 

Related research projects:

Exploring the role of nature-based solutions for social-ecological resilience 

Sustain-Cocoa: Sustainable sourcing policies for biodiversity protection, climate mitigation, and improved livelihoods in the cocoa sector

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In a new paper out in the journal Nature Sustainability, researchers explore the climate–biodiversity–society (CBS) nexus as it relates to the implementation of nature-based solutions (NbS) in the urban context. The article, Global mapping of urban nature-based solutions for climate change adaptation, looks at 216 urban interventions and 130 cities worldwide.

The analysis focused on the use of NbS for climate change adaptation in relation to the CBS nexus, and found that current practice is limited in how comprehensively it can address many of these intersectional challenges. Their research also found that urban NbS knowledge was biased towards the Global North, which led to an underrepresentation of challenges faced by the Global South.

One of the limits they found to the transformative capacity of NbS in urban environments was the lack of engagement with the private sector. Their results showed that most NbS interventions in cities were implemented and funded by local governments and public bodies. These are entities with often highly constrained budgets and shifting priorities which can result in NbS failing to reach their full ecological and technical potential. However, the researchers note that nature-based interventions are often underutilized tools in reaching socio-economic goals towards urban transformation with major potential for further integration.

The authors also point out a need for increasing knowledge sharing strategies across climates and contexts. While there is already knowledge transfer surrounding large scale projects and developments, there is a distinct lack of information flow regarding projects which address Global South focused NbS strategies. While facing exacerbated socio-economic challenges, urban environments in the Global South are more likely to face severe exposure to climate impacts such as rising temperatures, drought, and coastal hazards. Therefore, the authors call for a more nuanced discussion on information sharing, with a focus on diverse interventions and contexts.

While the article focuses on ways to improve the adoption and implementation of NbS moving forward, they also highlight current bright spots within global practice. In many urban environments, NbS can have a transformative capacity in addressing the challenges of the CBS nexus. They found examples of these urban ‘bright spots’ in the Maldives; Durban, South Africa; São Paulo, Brazil; and Hamburg, Germany.

The paper wraps up with two key recommendations to consider moving forward. The first is that research must focus on filling key knowledge gaps and disparities, such as those that exist between the Global North and Global South. The second is that urban policies must interact with all parts of the CBS nexus in order to capture and address the multiple dimensions of climate vulnerability. Together these efforts could help unlock the full potential and transformative capacity of NbS within the urban environment.

To learn more read the full article; Global mapping of urban nature-based solutions for climate change adaptation in Nature Sustainability.

Collas et al. 2022

A new study highlighted by the British Ecological Society shows that the most cost-effective way for the UK to reach its environmental goals is to pay farmers to create woodlands and wetlands. The government has made ambitious international commitments to halt and reverse nature declines by 2030 and to reach net zero carbon emissions by 2050.

In the December 2022 study published in the journal People and Nature, Collas et al. show that compensating farmers to restore native habitats can deliver UK climate and biodiversity targets at half the taxpayer cost of integrating nature into land managed for food production. This is in contrast to most current incentive schemes in the UK which place an emphasis on incentivizing land-sharing approaches that reduce crop-yield in order to support biodiversity and scale down net emissions.

The team instead proposes a land-sparing approach be implemented in the UK, with their research suggesting that it would cost taxpayers just 48% of the current cost of land-sharing techniques in order to achieve the same outcomes. The current strategy includes adding hedgerows to fields and reducing pesticides, which constitutes almost £600m a year of taxpayer money directed towards these initiatives. According to the research team, the implementation of these land sharing farming techniques also could lead to the UK losing more than 30% of its food production capacity.

In the study researchers interviewed 118 farmers, who together manage 1.7% of England’s arable lands, and asked them what cost incentives they would require to implement either land-sparing or land-sharing techniques. When provided with a wide variety of agricultural approaches, nature interventions and payment rates, the farmers were willing to accept lower payments per hectare for land sharing practices on average.

In regards to their findings, senior researcher on the study and Cambridge Professor Andrew Balmford stated that “Greater incentives for farmers to create woodlands and wetlands will deliver for wild species and climate mitigation at half the cost to the taxpayer of the land-sharing approach that currently receives ten times more public funding.”

As the UK continues to formulate its post-Brexit environmental strategy these studies can help inform improvements to England’s new Environmental Land Management Schemes.

Learn more about this research by reading the British Ecological Society’s press release and the full study titled The costs of delivering environmental outcomes with land sharing and land sparing in People and Nature.

Jackson et al. 2022

In a new Ecology and Evolution study, short-range multispectral imaging in a temperate calcareous grassland is demonstrated to provide indicators of grassland biodiversity metrics at high spatial resolution.

Image sensing technology developments are improving the cost-effectiveness of biodiversity monitoring efforts, yet logistical difficulties impede broad-scale implementation and use in characterizing biodiversity at different spatial scales. The use of unmanned aerial vehicle (UAV) technology with multispectral sensors has far-reaching potential to provide cost-effective and high-resolution monitoring of biodiversity in complex environments. In order to test this potential, the authors investigated the utility of multispectral imaging technology from commercially available unmanned aerial vehicles (UAVs, or drones) in estimating biodiversity metrics at short-range (<10 m image recording height) in a temperate calcareous grassland ecosystem in Oxfordshire, UK.

Species differences in the reflectance of electromagnetic radiation, such as m easured by UAV technology, are a promising target to estimate plant biodiversity using multispectral image data. The effectiveness of the multispectral images at estimating ground-truthed biodiversity metrics from in-situ botanical surveys for 37 – 1 m × 1 m quadrats were tested. For this, a suite of moments were calculated (coefficient of variation, standard deviation, skew, kurtosis) for the distribution of radiance from multispectral images at five wavelength bands (Blue 450±16 nm; Green 560±16 nm; Red 650±16 nm; Red Edge 730±16 nm; Near Infrared 840±16 nm).

The study found positive associations between the variation in the detected spectral radiance and two biodiversity indices. The study also found find that the average coefficient of variation in spectral radiance was consistent and highly repeatable, across sampling days and recording heights. The positive associations with biodiversity indices were consistent irrespective of the image recording height (2-8 m), but there were reductions in estimates of spectral diversity with higher UAV recording heights. UAV imaging were found to be much more time efficient that in-situ botanical surveys; reducing sampling time by a factor of 16.

The study results demonstrate the utility of multispectral radiance moments as an indicator of biodiversity in this temperate calcareous grassland at a fine spatial resolution using a widely available UAV monitoring system with a coarse spectral resolution. This adds to the growing body of literature highlighting links between spectral and species diversity, highlighting the potential for UAV technology with multispectral sensors for cost-effective and high-resolution monitoring of biodiversity.

Learn more in the full Ecology and Evolution study, Short-range multispectral imaging is an inexpensive, fast, and accurate approach to estimate biodiversity in a temperate calcareous grassland.

 

Keith et al. 2022

A new paper in Nature, A function-based typology for Earth’s ecosystems, presents the International Union for Conservation of Nature (IUCN) Global Ecosystem Typology. It is a conceptually robust, scalable, spatially explicit approach for generalizations and predictions about functions, biota, risks and management remedies across the entire biosphere.

The typology is intended for policy, media and technical specialists interested in better understanding ecosystem dynamics. Supported by maps, infographics and pictures, it also provides a summary as well as in-depth information on notions such as realms, biomes, functional groups and more technical notions such as ecological drivers, distribution  that can help specialists to assess ecosystems.

The comprehensive classification framework of Earth’s ecosystems integrates their functional and compositional features, and helps identify the ecosystems that are most critical for biodiversity conservation, research, management and human wellbeing into the future. The typology was created through a large collaboration across disciplines, and places the world’s ecosystems into a single theoretical context, that can be used to guide ecosystem policy and management from global to local scales. It can also support knowledge transfer for ecosystem-specific management and restoration, globally standardized ecosystem risk assessments, natural capital accounting and progress on the post-2020 global biodiversity framework vision of ‘living in harmony with nature’.

The IUCN Global Ecosystem Typology is the first globally consistent classification of ecosystems that reflects functional responses to change and management within individual ecosystems, and their variable biota, service provision and relative exposure to risks.

Learn more in the full Nature paper A function-based typology for Earth’s ecosystems.

Chaplin-Kramer et al. 2022

A recent Nature Ecology & Evolution paper by Chaplin-Kramer et al. maps nature’s contributions to people globally, and determines the critical areas where their magnitude is the highest and where they provide the highest potential human benefit.

The authors define critical natural assets as the natural and semi-natural ecosystems that provide 90% of the total current magnitude of 14 types of nature’s contributions to people (NCP), and these critical natural assets were then mapped at 2 km resolution. The results show that conserving 30% of the Earth’s land and 24% of coastal waters would sustain 90% of nature’s current contribution to people in every country.

Over 80% of the natural asset locations identified as critical for 12 local benefits are also critical for climate regulation benefits at the global scale (via carbon storage and moisture recycling); together these account for 44% of Earth’s lands. Some ecosystems are crucial for the whole planet, but the results reveal that every country has critical areas for local communities.

In addition, these areas overlap substantially with cultural diversity (areas containing 96% of global languages) and biodiversity (covering area requirements for 73% of birds and 66% of mammals). At least 87% of the world’s population live in the areas benefitting from critical natural assets for local-scale NCP, while only 16% live on the lands containing these assets. 6.1 billion people live within one hour’s travel of these areas, while 3.7 billion people live downstream of them, highlighting the importance of putting local people at the centre of discussions about biodiversity & conservation.

The results reveal that explicitly prioritizing critical natural assets and the NCP they provide could simultaneously advance development, climate and conservation goals, yet many of the NCP areas mapped here are left out of international agreements focused on conserving species or mitigating climate change.

Learn more in the full Ecology & Evolution paper, Mapping the planet’s critical natural assets.

Pacheco & Meyer, 2022

A recent Nature Communications study, Land tenure drives Brazil’s deforestation rates across socio-environmental contexts, investigates the relationship between land tenure and deforestation rates in Brazil, revealing that poorly defined land rights lead to increased deforestation rates. The privatisation of such lands can only mitigate this effect if combined with strict environmental policies.

The researchers analysed 33 years of agriculture-driven deforestation across Brazilian tropical forestlands to compare six land-tenure regimes (undesignated/untitled, private, strictly-protected and sustainable-use protected areas, indigenous, and “quilombola” lands held by Afro-Brazilian communities) and their respective rates of deforestation. Land-tenure determines how land can be used and by whom meaning that changes to these regimes have implications for forests within them, exacerbated by the increasing pressure from agroeconomic development.

The regime with an clear associated increase in deforestation was publicly owned lands with poorly defined tenure rights. Such lands are not designated for any use but can be inhabited by rural settlers without guaranteed property rights. There are almost one hundred million hectares of such inhabited publicly owned land in Brazil.

To reduce the deforestation that occurs within undesignated and untitled forestlands, privatising the land alongside strict environmental policies can be used, such as the Forest Code in the Amazon, which requires landowners to maintain 80% of their land under native vegetation. The research indicates that both strictly protected areas and sustainable-use protected areas were most effective at reducing deforestation rates while privatizing conservation regimes or lands held by indigenous peoples and local communities would likely increase the risk of deforestation across Brazil.

Read more in the full Nature Communications study, Land tenure drives Brazil’s deforestation rates across socio-environmental contexts.

Pendrill, F., et al. 2022

A recent study in Science, Disentangling the numbers behind agriculture-driven tropical deforestation, tropical deforestation from 2011 to 2015 was investigated, and it was found that 90-99% of all deforestation was driven directly or indirectly by agriculture, yet only 45-65% was converted into productive agricultural land.

Although different land uses and commodities can interact to drive deforestation, it was found that pasture expansion forms the most important driver, accounting for around half of the deforestation resulting in agricultural production across the tropics. Oil palm and soy cultivation accounted for at least a fifth, while 6 crops—rubber, cocoa, coffee, rice, maize, and cassava – while regionally variable and with higher uncertainty, were found to likely account for most of the remainder.

The study has also enabled a more precise estimate of how much forest has been converted to agricultural land across the tropics, with a range of 6.4 to 8.8 million hectares per year. The remaining uncertainty in such estimates are a result of only partial expansion of active agricultural production on the deforested land, with forests and other ecosystems also cleared for abandoned land speculation and projects, land unsuitable for cultivation, and fires that damaged the remaining forests that neighboured cleared areas.

Data availability and trends were found to vary across regions, suggesting complex links between agriculture and forest loss, with important implications for policy efforts to understand and address these factors, such as supply chain measures to reduce forest loss, and rural development policy in producer countries. To ensure effective NbS, interventions need to work in support & partnership with producers, consumer markets and governments, so that supply chain and demand-side measures also address the substantial indirect forest loss resulting from agriculture-driven deforestation.

Read more in the full Science paper, Disentangling the numbers behind agriculture-driven tropical deforestation.

Doelman, J.C. & Stehfest, E. 2022

A recently published Matters Arising response to the 2020 Nature paper, Global priority areas for ecosystem restoration (Strassburg et al., 2020), asserts that overstating the role of restoration in preventing climate change may undermine mitigation efforts and distract from the core task of reducing carbon emissions.

Strassburg et al. presented a high-resolution method to identify optimal locations for ecosystem restoration globally for conserving biodiversity and increasing carbon sequestration, and present as one conclusion that 30% of total CO2 increase in the atmosphere since the Industrial Revolution can be sequestered by restoring 15% of converted lands. Doelman & Stehfest argue that this is an overly optimistic message that is partly based on inaccurate assumptions, and that this creates unrealistic expectations for the contribution of restoration to the mitigation of climate change.

For converted lands, Strassburg et al. assume that current aboveground carbon stocks are 6 tonnes of carbon per ha (tC ha−1). However, especially in locations identified as priority areas, such as southeast Asia, the western African coastal area and the Caribbean, carbon stocks in converted lands are in fact much higher because they mostly consist of mosaic and agroforestry-type landscapes. Such areas make up a large share of the highlighted 15% priority areas by Strassberg et al., and therefore, the higher reference carbon stocks result in substantially reduced carbon-sequestration potential.

The response also highlights the feasibility issue of unconstrained restoration with large-scale abandonment of agriculture in high priority locations that are mostly located in tropical regions. About 50% of all agricultural land in southeast Asia, Central Africa, the Caribbean and Mesoamerica would need to be restored in the case proposed by Strassberg et al., which would have enormous impacts on the agricultural system and beyond. Doelman & Stehfest suggest that the case with national targets (a maximum of 15% agricultural abandonment) represents a more realistic approach to restoration and mitigation potential.

Read more in the full Nature Matters Arising article, The risks of overstating the climate benefits of ecosystem restoration. A response to this from Strassberg et al. can be found at Reply to: The risks of overstating the climate benefits of ecosystem restoration. In the response Strassberg et al. counters the analysis from Doelman & Stehfest regarding estimates of land-use and carbon stocks, and summarises that: ‘Achieving ecosystem restoration at planetary scales targeted by multiple international agreements and processes will be very complex, involving multiple practical, ecological, social and ethical considerations that need to be dealt with appropriately. However, the resulting contributions to some of our greatest global challenges, as shown in our Article and reaffirmed in the analyses summarized here, are vast and can hopefully motivate all relevant stakeholders to take appropriate actions towards realizing this potential.’

A previous response to Strassburg et al., 2020 was also published in July: Fleischman, F., et al. Restoration prioritization must be informed by marginalized people. Nature 607, E5–E6 (2022). Fleischman et al. warn that the large-scale, broad characterization of areas as ready for restoration, such as by Strassburg et al. 2020, risks displacing marginalized people, compromising food security and undermining democratic processes.

The concerns raised by Fleischman et al. and Doelman & Stehfest highlight the importance of including local and Indigenous communities in nature-based solutions such as ecosystem restoration. IPLCs depend highly on nature-based resources for their livelihood and have extensive, traditional knowledge about nature conservation. Therefore, the collaboration of scientists and policy-makers with organizations representing people who live on and manage lands is likely to provide the best identification of land-use priorities in the face of ongoing climate change.

Allen, M.R., et al. 2022

A new study Net Zero: Science, Origins, and Implications in Annual Review of Environment and Resources, co-authored by NbSI Technical Director Cecile Girardin and ECI Oxford colleagues, includes examination of the role of nature-based solutions in net zero.

The review explains the science behind the drive for global net zero emissions, why this is needed to halt the ongoing rise in global temperatures, and examines carbon removal/mitigation measures including NbS.

The paper argues that while NbS provide opportunities to reduce CO2 emissions alongside substantial co-benefits, it must in future also counter food production and global warming-induced biosphere carbon emissions. Relying on the biosphere to partially or fully compensate for continued production of CO2 from burning fossil fuels also carries risks, including rerelease of carbon to the atmosphere because land-use practices change, pathogen or invasive pest outbreaks (an acute problem in low-diversity forests such as temperate or island ecosystems), or risks due to climate change itself increasing the likelihood of carbon loss from ecosystems. NbS are therefore unlikely to be scaled sufficiently to compensate for ongoing fossil fuel emissions past mid-century

The review argues that what matters is not the precise makeup of emissions & removals, but the sustainability of the net zero strategy, and its implications for global temperature over multidecadal timescales.

Read the full paper: Net Zero: Science, Origins, and Implications

Guerry et al. 2022.

A new study in npj Urban Sustainability reveals the add-on benefits of NbS such as conserving marshlands and restoring beaches, which are protecting against sea-level rise as well as concrete sea walls. This is in addition to further additional benefits including climate change mitigation through carbon storage, nutrient pollution reduction, and opportunities for recreation, incentivising policymakers to prioritise NbS for sea-level rise.

California is amongst the US states most exposed to sea-level rise, with the San Francisco Bay Area is particularly at-risk. Within the Bay Area, San Mateo County is at particular risk of exposure to flooding and erosion over the next 50–100 years, with the population more vulnerable to the effects of sea-level rise due to demographic factors including age, race, income, and housing vulnerability.

Three scenarios were modelled for seal-level rise adaption, with input from stakeholder workshops and testing of the suitability of stretches of shoreline for restoration of different coastal habitats. Scenario 1 modelled concreate seawalls across the  San Francisco Bay coastline. Scenario 2 considered conservation and restoration projects currently underway or in various stages of planning, such as rehabilitation of salt ponds and the addition of a beach in front of a levee. Scenario 3 explored additional NbS projects, such as protecting marshlands and restoring native seagrasses and oyster beds along the coastline.

Extra benefits from adaptation options were modelled. Scenario 2 – with NbS projects already being implemented – provides 6 times more storm water pollution reduction than concrete seawalls. Scenario 3 including proposed additional NbS projects, would result in 8 times more storm-water pollution reduction than traditional approaches.

The results informed guiding principles for the county’s sea-level rise adaptation planning, including to prioritize NbS, use an inclusive, equitable, and community-based process to make decisions, and rigorously track the process to reduce vulnerability, risks, and impacts. This case adds to the evidence base that NbS help protect coastlines while yielding diverse ecosystem services.

Read more in the full npj Urban Sustinability paper, Protection and restoration of coastal habitats yield multiple benefits for urban residents as sea levels rise.

Matthews et al. 2022.

A recent study in Communications Earth & Environment has found that temporary nature-based carbon storage (NbCS) can decrease the peak temperature increase associated with anthropogenic climate change, but only if implemented as a complement (and not an alternative) to ambitious fossil fuel CO2 emissions reductions.

The study utilised a global climate model featuring two Shared Socioeconomic Pathway (SSP) climate mitigation scenarios simulating temperature change –  those of weak and ambitious greenhouse gas emissions reductions. In the relatively weak emissions reduction scenario, carbon emissions continue through to 2100, whereas in the ambitious scenario carbon emissions reach net-zero by 2050. Alongside the two SSP scenarios, three idealized NbCS scenarios were used for modelling pathways, based on estimates of the feasible potential of NbCS-based carbon removal. The scenarios included an increasing rate of removal beginning in 2020, and reaching a maximum removal rate at 2030 of 3.64 and 10.4 GtCO2 per year relative to the baseline scenario emissions. In two of the scenarios, this rate of removal then decreased after 2030 to zero at the year 2056, resulting in cumulative removals of 81 and 173 GtCO2 in the two scenarios; in the third, a  higher removal rate of 10.4 GtCO2 per year was sustained until the year 2050 before decreasing it to zero at 2056, leading to a cumulative removal of 316 GtCO2.  In all three NbCS scenarios, the removed carbon was subsequently fully or partially (50%) returned to the atmosphere after 2056.

The researchers used an intermediate-complexity global climate model to simulate the near-term rate of temperature increase, the peak temperature change, and the long-term temperature trajectory in response to a set of emissions scenarios which include both global decarbonization efforts and temporary land-based enhanced carbon storage. In both scenarios, the carbon storage is temporary due to the losses back to the atmosphere from forests as a result of disturbances such as wildfire or deforestation. The resulting nature-based climate solutions are anticipated to withdraw carbon from the atmosphere over the next 30 years then slowly release the carbon during the second half of the century.

The study also highlighted the additional social and environmental benefits of nature protection and restoration for local and Indigenous communities, in addition to storing carbon to for climate change mitigation. The inherent value of biodiversity, water and air quality are and the efforts to protect them also aid in building resilience to climate change for communities.

Read more in the full Communications Earth & Environment paper, Temporary nature-based carbon removal can lower peak warming in a well-below 2 °C scenario.

Shin et al. 2022

A review in Global Change Biology examines conservation actions which have the largest potential for mitigation of climate change, highlighting that conservation actions have a variety of benefits and few trade-offs with climate change mitigation.

The study looked at the extent to which actions taken to halt or reverse biodiversity loss have consequences for these climate change mitigation processes, and how, when and where the form and strength of such links vary. The study identifies direct co-benefits in 14 out of the 21 action targets of the draft post-2020 global biodiversity framework of the Convention on Biological Diversity. These targets for 2030, which aim to contribute to the 2050 Vision for Biodiversity, were not primarily designed to have direct or indirect impacts on climate change mitigation, but have potential contributions to carbon capture, storage and sequestration, the albedo effect and non-CO2 GHG fluxes.

As the relationships between biodiversity and climate mitigation are context and scale-dependent, the study showcases local biodiversity conservation actions that can be incentivized, guided and prioritized by global objectives and targets. These actions include:

• Restoring degraded natural areas and retaining existing intact wilderness areas.
• Implementing a well-connected and effective system of protected areas.
• Recovering and conserving wild species.
• Ensuring sustainable harvesting of wild species, food production and supply chains.
• Reducing pollution from excess nutrients.
• Supporting the productivity, sustainability and resilience of biodiversity in agricultural and other managed ecosystems.
• Increasing benefits from biodiversity and green/blue spaces in urban areas.
• Mainstreaming biodiversity.
• Eliminating unsustainable consumption patterns.
• Eliminating incentives harmful for biodiversity.

A selection of case studies were then collated from across different continents, oceans and latitudes that cover a diversity of conservation measures, types of NCP, needs of local communities, socio-economic contexts and governance situations. These were used to unpack the enabling conditions (including incentives and governance factors) that have been effective in fulfilling multifunctional and multiple-use land- and sea-scape objectives simultaneously. Synergistic benefits are strongly dependent the biomes, ecosystem uses, and sectoral interactions under consideration, with win-win synergies and trade-offs hard to achieve at all parts of a landscape or seascape; instead becoming progressively easier at the multifunctional and multiple-use land- and sea-scape level.

Improving the linkages between the different scales of actions was found to be essential for successfully implementing joint biodiversity and climate actions, with locally motivated actions incentivized, guided and prioritized by international objectives and targets, rigorously based on evidence to avoid oversimplified objectives. The study highlighted the important of considering local to global policies and practices in an integrated and consultative way in mixed-use land- and sea-scapes, so that win-win synergies and nature’s contributions to people can be maximized.

Read more in the full Global Change Biology paper, Actions to halt biodiversity loss generally benefit the climate.

Hua et al. 2022

A recent study in Science has revealed the differences in the ecosystem services and biodiversity benefits of native forests compared to tree plantations. Diverse native forests were found to perform better in terms of supporting biodiversity, above-ground carbon storage, soil erosion prevention, and water provisioning, compared to simple tree plantations. Plantations were found to perform better for wood production.

The synthesis study was based on a database consisting of almost 26,000 records from 264 studies conducted in 53 countries, and found that environment-oriented ecosystem services (aboveground carbon storage, soil erosion control, and water provisioning), as well as biodiversity, are delivered better by native forests than by tree plantations. Soil erosion control and water provisioning showed the greatest difference, with plantations significantly less effective at water provisioning than native forests in drier climates with increased water scarcity. Additionally, the study also found that abandoned plantations no longer used for wood production do not deliver the ecosystem services or biodiversity benefits of native forests, highlighting opportunities for restoring them to native forests to deliver environmental benefits.

Delivery of these greater ecosystem benefits by native forest restoration results in a trade-off with wood production due to the yield advantage of plantations over restored native forests as measured in wood volumes. Plantations use fast-growing species which tend to grow tall and straight, and can include active management with fertilisers and weeding. Native forests contain multiple tree, shrub, and herbaceous species without being managed for growth, with wood production therefore possibly less efficient.

The study reveals the importance of restoration of native forests as a nature-based solution by delivering both biodiversity conservation and ecosystem services, with some trade-offs in wood production. Therefore, if wood production is not the primary goal, site-appropriate measures including unassisted and assisted natural regeneration and active planting of diverse native species should be used for native forest restoration. Where forest restoration goals include wood production, trade-offs between environmental and production outcomes must be incorporated into decision making.

The study also highlights the needed future research into the trade-offs between wood production, biodiversity benefits and ecosystem services for a range of restored forest covers. This would ensure that forest restoration actions provide environmental gains while meeting any wood production goals.

Read the full Science paper, The biodiversity and ecosystem service contributions and trade-offs of forest restoration approaches.

 

 

Vadya Sarira et al 2022.

A new study in Nature Sustainability by researchers at the National University of Singapore (NUS) reveals the social and environmental benefits of forest protection in South-east Asia.

This region contains 196 million ha of tropical forests, many of which are under threat from agricultural expansion and other economic activities. Large-scale carbon projects in the region focus on avoided deforestation as a nature-based climate solution, with countries such as Cambodia committing to a ~60% reduction of their emissions from forestry in their Nationally Determined Contributions by 2030. Protecting forests through carbon projects throughout Southeast Asia could avoid 835 ± 348 MtCO₂e of emissions from deforestation across the region per year

In addition to the carbon benefits, the study found that people living in or around forests within carbon projects experience co-benefits including pollination service for pollinator-dependent agriculture and water quality regulation, as well as biodiversity conservation.

Forest carbon projects in proximity to agricultural lands provide important foraging and nesting habitats for wild pollinators, which both ensure ecosystem health and support pollinator-dependent agricultural production and nutritional services within the immediate vicinity. Forest absorption of nutrients such as nitrogen also reduces the amount of nutrients that flow into freshwater habitats within the area’s watersheds and thereby improve the quality of water flowing downstream, reducing the need for added treatment of potable water. Additionally, protecting forests through carbon projects in the region would conserve 25 ± 3 Mha of KBAs (sites that contribute greatly to the global persistence of biodiversity), half of all terrestrial forest KBAs in the region.

The study reveals that investment in the protection of forests, their natural capital and their ongoing provision of services through carbon projects enables a financially viable and sustainable means of addressing other socio-economic and environmental issues beyond climate change. This demonstrates the potential of carbon finance to meet global climate and human development ambitions.

Read the full Nature Sustainability paper, Co-benefits of forest carbon projects in Southeast Asia.

Schulte et al  2022.

A new study in Environmental Research Letters presents a systematic review of the contextual factors that influence the implementation of natural climate solutions (NCS).

By examining a large global collection of research case studies from the peer-reviewed literature, the study synthesizes and maps the bottom-up evidence on NCS. This is is then used to clarify the definition of NCS, including in the context of nature-based solutions and other ecosystem-based approaches to addressing climate change.

The research trends, opportunities, gaps, and biases were examined to discern the factors that may affect geographic variation in NCS implementation, and what trends may be generalizable to inform best practices in policy discussions. The reviewed studies included were found to be dominated by a focus on tropical regions and activities in forest landscapes. Implementation of NCS was found to be influenced by multiple interlinked enabling factors and the interaction between them. Particular drivers were found to include engagement of indigenous peoples and local communities, performance-based finance, and technical assistance, while important interactions between factors were social and political.

The review also highlights remaining challenges to ensuring enabling factors in practice. Projects can be slow to progress or provide tangible benefits due to insecure finance or poor governance, while public perception and creating trust and confidence in project developers can greatly impact implementation. Successful participation was also found to required awareness such as through education, dialogue, or an existing connection to the land, which can also strengthen the longevity of NCS activities by promoting buy-in among indigenous peoples and local communities.

The study provides a broad assessment of implementation to inform meso-scale planning and designing non-quantitative indicators for monitoring NCS, highlights key research questions, the current discourse and state of research, the realities on-the-ground, and challenges widely held assumptions and narratives around the potential of NCS. Given that climate change is taking place across all social, economic, political, institutional, financial, technical and biophysical contexts, the study emphasises the need to prioritise  research and policy that understands and balances the enabling factors within these realms. By examining these factors, the characteristics of NCS are discerned that are relevant to designing and implementing socially just solutions and achieving long-term positive change.

Read the full paper, What influences the implementation of natural climate solutions? A systematic map and review of the evidence, in Environmental Research Letters.

 

Cook-Patton et al 2021.

A recent study in Nature Climate Change, led by scientists from The Nature Conservancy, outlines a hierarchy for decision-making regarding protecting, managing, and restoring natural systems for climate mitigation.

A series of approaches to maximising the use of Natural Climate Solutions (NCS) to tackle climate change were compared against four key criteria: magnitude of climate benefit; immediacy of impact; cost-effectiveness; and co-benefits for people and nature.  Analysis of the results were then used to propose a  robust decision-making hierarchy designed to aid public and private sector organisations in deploying such nature-based approaches at scale.

The hierarchy utilises a general rule of thumb to protect, manage and then restore lands – prioritising establishing stronger protection and management protocols for existing climate-critical landscapes like forests, wetlands and grasslands given their ability to reap cost-effective carbon-storing benefits. It also reveals how the key criteria explain alternative prioritisation and portfolio schemes, as the framework aims to optimise the effectiveness of natural climate solutions when resources are constrained.

The NCS routes of protection, improved management and restoration are not mutually exclusive, and in planning and practice they can be highly complementary. As the priorities at the national and local scales depend on context (for example, biophysical, political, institutional, economic and socio-cultural factors), the framework provides a process to improve the overall impact of climate mitigation and biodiversity conservation, in place of more rigid prescriptions. The authors note that NCS do not replace or delay the large scale decarbonisation needed to keep global warming below 2 °C, but NCS land-stewardship actions aid in this by capturing or reducing greenhouse gas (GHG) emissions; through protecting existing ecosystems, improving the management of working lands or restoring natural ecosystems.

Read the full paper, Protect, manage and then restore lands for climate mitigation, in Nature Climate Change.

 

Fedele et al. 2021

A recent study in Global Environmental Change led by Conservation International Europe investigated where people depend the most on locally available natural resources for their basic human needs, such as energy, water, housing and livelihoods. The study aimed to improve the current limited understanding of the importance of nature in directly supporting people’s basic needs, and the resulting risk of perpetuating poor or unsustainable development outcomes.

This pioneering study utilized 5 million household interviews across 85 tropical countries to identify that 1.2 billion people, or 30% of the population across tropical countries, are highly dependent on nature. Nature-dependent people were defined in the study as those that directly depend on locally available natural resources for at least three of the four basic needs considered, i.e. housing materials, water, energy, and occupation. These households were identified by assessing the amount of direct use of natural resources for basic needs, with this then used as a proxy indicator for identifying their dependencies on natural resources.

The largest number of highly nature-dependent people on the continental scale were found to live in tropical Asia-Pacific (636 million or 27% of the total population in that region), followed by Africa (478 million or 48%) and the Americas (48 million or 9%). Looking at the country level, the largest proportion of people who were found to be highly dependent on nature per country was found to be in Africa, with more than 75% of people in several African countries highly depend on nature, especially in the central and eastern regions, including Burundi, the Democratic Republic of Congo, Chad, Ethiopia, Rwanda, Central African Republic, Niger, and Madagascar. The total number of nature-dependent people identified increased to 2.7 billion (or 69% of populations across tropical countries) when including people that are dependent on nature for at least one basic need.

The study also demonstrated a negative correlation between nature-dependent people and the human development index (a measure of the standard of living of a citizen which combines life expectancy, education, and income per capita indicators). Such a correlation was determined to reflect the inter-dependencies between human development and nature, empirically supporting the positive association between high poverty and high human dependency on nature, which had not been previously shown at the global level.

The authors highlight that understanding the needs of these peoples is crucial for planning conservation and development interventions, given that a high direct dependency on nature makes people particularly sensitive to changes in climate, land cover, and land tenure. The study then recommends that nature-based strategies that protect, restore or sustainably manage ecosystems must be carefully designed to promote inclusive human development alongside environmental benefits.

Read the full paper, Nature-dependent people: Mapping human direct use of nature for basic needs across the tropics, in Global Environmental Change.