Co‐benefits of planting species mixes in carbon projects

The carbon market offers a unique opportunity to achieve large‐scale ecological restoration of degraded agricultural landscapes. Here, we outline some of the benefits of planting mixes of native species rather than monocultures in carbon plantings as a step towards creating biodiverse carbon‐rich forests and woodlands in Australia. We highlight the gaps in our knowledge and emphasise the importance of setting benchmarks for carbon projects to maximise their potential to deliver co‐benefits such as habitat provision for wildlife. On the whole, we are optimistic that ongoing refinement of joined biodiversity conservation and carbon credit initiatives will help to develop a carbon market that can drive ecological restoration of Australian agricultural landscapes.     

Restoration of Biodiversity and Ecosystem Services on Agricultural Land

Cultivation and cropping are major causes of destruction and degradation of natural ecosystems throughout the world. We face the challenge of maintaining provisioning services while conserving or enhancing other ecosystem services and biodiversity in agricultural landscapes. There is a range of possibilities within two types of intervention, namely “land sharing” and “land separation”; the former advocates the enhancement of the farmed environment, but the latter a separation between land designated for farming versus conservation. Land sharing may involve biodiversity-based agricultural practices, learning from traditional farming, changing from conventional to organic agriculture and from “simple” crops and pastures to agro-forestry systems, and restoring or creating specific elements to benefit wildlife and particular services without decreasing agricultural production. Land separation in the farmland context involves restoring or creating non-farmland habitat at the expense of field-level agricultural production—for example, woodland on arable land. Restoration by land sharing has the potential to enhance agricultural production, other ecosystem services and biodiversity at both the field and landscape scale; however, restoration by land separation would provide these benefits only at the landscape scale. Although recent debate has contrasted these approaches, we suggest they should be used in combination to maximize benefits. Furthermore, we suggest “woodland islets”, an intermediate approach between land abandonment and farmland afforestation, for ecological restoration in extensive agricultural landscapes. This approach allows reconciliation of farmland production, conservation of values linked to cultural landscapes, enhancement of biodiversity, and provision of a range of ecosystem services. Beyond academic research, restoration projects within agricultural landscapes are essential if we want to halt environmental degradation and biodiversity loss.     

The role of natural regeneration to ecosystem services provision and habitat availability: a case study in the Brazilian Atlantic Forest

Natural regeneration provides multiple benefits to nature and human societies, and can play a major role in global and national restoration targets. However, these benefits are context specific and impacted by both biophysical and socioeconomic heterogeneity across landscapes. Here, we investigate the benefits of natural regeneration for climate change mitigation, sediment retention and biodiversity conservation in a spatially explicit way at very high resolution for a region within the global biodiversity hotspot of the Atlantic Forest. We classified current land‐use cover in the region and simulated a natural regeneration scenario in abandoned pasturelands, areas where potential conflicts with agricultural production would be minimized and where some early stage regeneration is already occurring. We then modeled changes in biophysical functions for climate change mitigation and sediment retention, and performed an economic valuation of both ecosystem services. We also modeled how land‐use changes affect habitat availability for species. We found that natural regeneration can provide significant ecological and social benefits. Economic values of climate change mitigation and sediment retention alone could completely compensate for the opportunity costs of agricultural production over 20 yr. Habitat availability is improved for three species with different dispersal abilities, although by different magnitudes. Improving the understanding of how costs and benefits of natural regeneration are distributed can be useful to design incentive structures that bring farmers’ decision making more in line with societal benefits. This alignment is crucial for natural regeneration to fulfill its potential as a large‐scale solution for pressing local and global environmental challenges.     

Growing biodiverse carbon‐rich forests

Regrowing forests on cleared land is a key strategy to achieve both biodiversity conservation and climate change mitigation globally. Maximizing these co‐benefits, however, remains theoretically and technically challenging because of the complex relationship between carbon sequestration and biodiversity in forests, the strong influence of climate variability and landscape position on forest development, the large number of restoration strategies possible, and long time‐frames needed to declare success. Through the synthesis of three decades of knowledge on forest dynamics and plant functional traits combined with decision science, we demonstrate that we cannot always maximize carbon sequestration by simply increasing the functional trait diversity of trees planted. The relationships between plant functional diversity, carbon sequestration rates above ground and in the soil are dependent on climate and landscape positions. We show how to manage ‘identities’ and ‘complementarities’ between plant functional traits to achieve systematically maximal cobenefits in various climate and landscape contexts. We provide examples of optimal planting and thinning rules that satisfy this ecological strategy and guide the restoration of forests that are rich in both carbon and plant functional diversity. Our framework provides the first mechanistic approach for generating decision‐makingrules that can be used to manage forests for multiple objectives, and supports joined carbon credit and biodiversity conservation initiatives, such as Reducing Emissions from Deforestation and forest Degradation REDD+. The decision framework can also be linked to species distribution models and socio‐economic models to find restoration solutions that maximize simultaneously biodiversity, carbon stocks, and other ecosystem services across landscapes. Our study provides the foundation for developing and testing cost‐effective and adaptable forest management rules to achieve biodiversity, carbon sequestration, and other socio‐economic co‐benefits under global change.     

Reduction in Lyme Disease Risk as an Economic Benefit of Habitat Restoration

Habitat restoration is costly and it is often necessary to justify the costs with evidence of benefits to society. These benefits are difficult to quantify because they are measured in terms of ecosystem services rather than currency. This paper introduces a somewhat novel restoration‐related ecosystem service, a reduction in the risk of tick‐borne disease, and incorporates it into a cost/benefit analysis of the restoration of a rare habitat. We use a cost‐of‐illness study to calculate the costs averted by preventing Lyme disease (LD), and a contingent‐valuation survey to estimate the benefit of biodiversity protection. The restoration, removal of an invasive tree, reduced the risk of LD by approximately 98%. Cost‐of‐illness studies show that the restoration would be financially justifiable if it averted 75 cases of LD per year. Given the local LD rate and the visitation rate to the preserve, the habitat restoration can plausibly be justified solely on the benefit of LD cases averted. However, as we do not know how many cases of LD are contracted in the preserve, we also establish the perceived value of protecting biodiversity in a contingent‐valuation survey. Results show that residents were willing to pay a significant fraction of the net cost of restoration to protect biodiversity. When these benefits are taken into account, the number of cases of disease that must be averted to justify remediation is reduced. This exercise spotlights an underappreciated ecosystem service that, when appropriate, can help establish the cost effectiveness of restoration.     

Can carbon credits fund riparian forest restoration?

Ecological restoration is increasingly called on to provide ecosystem services (ES) valuable to humans, as well as to benefit biodiversity and improve wildlife habitat. Where mechanisms to pay for ES exist, they may serve as incentives to embark on habitat restoration projects. We evaluated the potential of newly established carbon markets in the United States to incentivize afforestation along riparian corridors, by comparing the income earnable by carbon offset credits with the costs of planting, maintaining, and registering such a restoration project in California. We used a 20‐year chronosequence of riparian forest sites along the Sacramento River as our model project. We found that carbon credits can repay more than 100% of costs after two decades of regrowth, if sufficient effort is put into sampling intensity in the first post‐restoration decade. However, carbon credits alone are unlikely to entice landowners currently engaged in agricultural activities to switch from farming crops to farming habitat.     

Objectives versus realities: Spatial,temporal, financial and social deficiencies in Australia’s public revegetation investment model

Past and continuing fragmentation and modification of ecosystems, as well as other threatening processes, cause ongoing biodiversity losses and species extinctions in Australia. At the same time as biodiversity declines, government funding for conservation and restoration is diminishing, leading to reduced action and greater reliance on private investment and community groups. In order to maintain and restore biodiverse ecosystems and the essential services they provide, both conservation of existing vegetation and habitat reconstruction are required. In this paper, we summarise the available data on planting area and cost from the Australian Government’s 20 Million Trees programme (2014–2020), the largest recent national‐scale revegetation incentives programme in Australia. We find that the current spatial scale of effort and investment in habitat reconstruction is insufficient to match the scale required to meet national conservation objectives. Furthermore, the funding rate ($/ha) and contracting arrangements are inadequate for the establishment of high‐quality self‐sustaining vegetation needed for the recovery of Australia’s threatened species and ecological communities. We estimate that the minimum amount of funding required for habitat reconstruction is at least five times higher than is provided for current national flagship programmes such as 20 Million Trees. We provide recommendations, designed to assist future habitat reconstruction programmes achieve their long‐term biodiversity objectives.     

Winners and losers of national and global efforts to reconcile agricultural intensification and biodiversity conservation

Closing yield gaps within existing croplands, and thereby avoiding further habitat conversions, is a prominently and controversially discussed strategy to meet the rising demand for agricultural products, while minimizing biodiversity impacts. The agricultural intensification associated with such a strategy poses additional threats to biodiversity within agricultural landscapes. The uneven spatial distribution of both yield gaps and biodiversity provides opportunities for reconciling agricultural intensification and biodiversity conservation through spatially optimized intensification. Here, we integrate distribution and habitat information for almost 20,000 vertebrate species with land‐cover and land‐use datasets. We estimate that projected agricultural intensification between 2000 and 2040 would reduce the global biodiversity value of agricultural lands by 11%, relative to 2000. Contrasting these projections with spatial land‐use optimization scenarios reveals that 88% of projected biodiversity loss could be avoided through globally coordinated land‐use planning, implying huge efficiency gains through international cooperation. However, global‐scale optimization also implies a highly uneven distribution of costs and benefits, resulting in distinct “winners and losers” in terms of national economic development, food security, food sovereignty or conservation. Given conflicting national interests and lacking effective governance mechanisms to guarantee equitable compensation of losers, multinational land‐use optimization seems politically unlikely. In turn, 61% of projected biodiversity loss could be avoided through nationally focused optimization, and 33% through optimization within just 10 countries. Targeted efforts to improve the capacity for integrated land‐use planning for sustainable intensification especially in these countries, including the strengthening of institutions that can arbitrate subnational land‐use conflicts, may offer an effective, yet politically feasible, avenue to better reconcile future trade‐offs between agriculture and conservation. The efficiency gains of optimization remained robust when assuming that yields could only be increased to 80% of their potential. Our results highlight the need to better integrate real‐world governance, political and economic challenges into sustainable development and global change mitigation research.     

Ecological restoration of farmland: progress and prospects

Sustainable agricultural practices in conjunction with ecological restoration methods can reduce the detrimental effects of agriculture. The Society for Ecological Restoration International has produced generic guidelines for conceiving, organizing, conducting and assessing ecological restoration projects. Additionally, there are now good conceptual frameworks, guidelines and practical methods for developing ecological restoration programmes that are based on sound ecological principles and supported by empirical evidence and modelling approaches. Restoration methods must also be technically achievable and socially acceptable and spread over a range of locations. It is important to reconcile differences between methods that favour conservation and those that favour economic returns, to ensure that conservation efforts are beneficial for both landowners and biodiversity. One option for this type of mutual benefit is the use of agri-environmental schemes to provide financial incentives to landholders in exchange for providing conservation services and other benefits. However, further work is required to define and measure the effectiveness of agri-environmental schemes. The broader potential for ecological restoration to improve the sustainability of agricultural production while conserving biodiversity in farmscapes and reducing external costs is high, but there is still much to learn, particularly for the most efficient use of agri-environmental schemes to change land use practice.     

Planning for Implementation: Landscape‐Level Restoration Planning in an Agricultural Setting

The conservation of biodiversity in highly fragmented landscapes often requires large‐scale habitat restoration in addition to traditional biological conservation techniques. The selection of priority restoration sites to support long‐term persistence of biodiversity within landscape‐scale projects however remains a challenge for many restoration practitioners. Techniques developed under the paradigm of systematic conservation planning may provide a template for resolving these challenges. Systematic conservation planning requires the identification of conservation objectives, the establishment of quantitative targets for each objective, and the identification of areas which, if conserved, would contribute to meeting those targets. A metric developed by systematic conservation planners termed “irreplaceability” allows for analysis and prioritization of such conservation options, and allows for the display of analysis results in a way that can engage private landowners and other decision makers. The process of systematic conservation planning was modified to address landscape‐level restoration prioritization in southern Ontario. A series of recent and locally relevant landscape ecology studies allowed the identification of restoration objectives and quantitative targets, and a simple algorithm was developed to identify and prioritize potential restoration projects. The application of an irreplaceability analysis to landscape‐level restoration planning allowed the identification of varying needs throughout the planning region, resulting from underlying differences in topography and settlement patterns, and allowed the effective prioritization of potential restoration projects. Engagement with rural landowners and agricultural commodity groups, as well as the irreplaceability maps developed, ultimately resulted in a substantial increase in the number and total area of habitat restoration projects in the planning region.     

Ecosystem Services in Conservation Planning: Targeted Benefits vs. Co-Benefits or Costs?

There is growing support for characterizing ecosystem services in order to link conservation and human well-being. However, few studies have explicitly included ecosystem services within systematic conservation planning, and those that have follow two fundamentally different approaches: ecosystem services as intrinsically-important targeted benefits vs. substitutable co-benefits. We present a first comparison of these two approaches in a case study in the Central Interior of British Columbia. We calculated and mapped economic values for carbon storage, timber production, and recreational angling using a geographical information system (GIS). These 'marginal' values represent the difference in service-provision between conservation and managed forestry as land uses. We compared two approaches to including ecosystem services in the site-selection software Marxan: as Targeted Benefits, and as Co-Benefits/Costs (in Marxan's cost function); we also compared these approaches with a Hybrid approach (carbon and angling as targeted benefits, timber as an opportunity cost). For this analysis, the Co-Benefit/Cost approach yielded a less costly reserve network than the Hybrid approach (1.6% cheaper). Including timber harvest as an opportunity cost in the cost function resulted in a reserve network that achieved targets equivalently, but at 15% lower total cost. We found counter-intuitive results for conservation: conservation-compatible services (carbon, angling) were positively correlated with each other and biodiversity, whereas the conservation-incompatible service (timber) was negatively correlated with all other networks. Our findings suggest that including ecosystem services within a conservation plan may be most cost-effective when they are represented as substitutable co-benefits/costs, rather than as targeted benefits. By explicitly valuing the costs and benefits associated with services, we may be able to achieve meaningful biodiversity conservation at lower cost and with greater co-benefits.     

Using prioritisation tools to strategically restore vegetation communities in fragmented agricultural landscapes

Restoring native habitats in heavily cleared and fragmented areas such as agricultural landscapes is important to maintain and increase remaining native floral and faunal communities. Identifying priority vegetation types for restoration – as well as the parcels of land where this restoration could take place at a landscape scale – may assist in strategically protecting these biodiversity assets. To prioritise the restoration of terrestrial habitats around an ecologically and culturally significant Ramsar‐listed wetland in South Australia, we used the spatial prioritisation tool Marxan. Originally designed for prioritising the protection of reserve areas, Marxan can also be used to identify parcels of land for restoration purposes. We tested how Marxan prioritised the restoration of four distinct vegetation types around the Coorong and Lower Lakes region of South Australia using the inverse of habitat remnancy as a cost and soil type and distance to ecologically significant bird species as a conservation feature. By prioritising restoration activities around certain landscape features, such as remnant areas, our results indicate that we would be able to strategically restore parcels of native habitat that would maximise biodiversity outcomes. This study highlights the need for robust input data, such as priority vegetation types and bird species associated with these habitats, to ensure informative modelling outputs. It also suggests that other measures, such as the cost of different land types, should be included in future restoration planning. Finally, we illustrate how prioritisation tools such as Marxan can be used by natural resource managers to restore areas within fragmented agricultural landscapes.     

Ecological Restoration in a Developing Island Nation: How Useful is the Science?

Restoration science is a relatively young branch of ecology that is growing in importance owing to the sheer scale and trend of habitat degradation worldwide and the range of strong benefits that it is seen to potentially carry. Although spearheaded mainly by developed countries, its usefulness at least for the conservation of biodiversity may be greatest in the developing world. Here we examine how Mauritius, a developing island nation that may be regarded as well equipped among developing countries in terms of access to restoration science, is using science to inform the ecological restoration of its degraded native habitats for biodiversity conservation. While Mauritius is known for a number of proactive and at times innovative approaches that may even be setting the pace worldwide, we found that the restoration activities which are impacting the largest areas and an overwhelming proportion of native biodiversity of the country sometimes remain averse to even basic ecological principles. This includes the removal from restoration areas of fast growing native pioneer species with proven nurse‐tree potential to be replaced by a multitude of nursery grown and much slower growing plants that would have naturally grown anyway. Besides representing setbacks to areas undergoing restoration, this elevates restoration costs in the face of scarcity of conservation resources and urgency to restore more than the tiny and isolated areas currently targeted. Research worldwide continues to improve restoration science but blockages to knowledge transfer can seriously undermine its impact where it is most needed.     

Costing conservation: an expert appraisal of the pollinator habitat benefits of England’s entry level stewardship

Pollination services provided by insects play a key role in English crop production and wider ecology. Despite growing evidence of the negative effects of habitat loss on pollinator populations, limited policy support is available to reverse this pressure. One measure that may provide beneficial habitat to pollinators is England’s entry level stewardship agri-environment scheme. This study uses a novel expert survey to develop weights for a range of models which adjust the balance of Entry Level Stewardship options within the current area of spending. The annual costs of establishing and maintaining these option compositions were estimated at £59.3–£12.4 M above current expenditure. Although this produced substantial reduction in private cost:benefit ratios, the benefits of the scheme to pollinator habitat rose by 7–140 %; significantly increasing the public cost:benefit ratio. This study demonstrates that the scheme has significant untapped potential to provide good quality habitat for pollinators across England, even within existing expenditure. The findings should open debate on the costs and benefits of specific entry level stewardship management options and how these can be enhanced to benefit both participants and biodiversity more equitably.     

Application of Assisted Natural Regeneration to Restore Degraded Tropical Forestlands

Assisted natural regeneration (ANR) is a simple, low‐cost forest restoration method that can effectively convert deforested lands of degraded vegetation to more productive forests. The method aims to accelerate, rather than replace, natural successional processes by removing or reducing barriers to natural forest regeneration such as soil degradation, competition with weedy species, and recurring disturbances (e.g., fire, grazing, and wood harvesting). Compared to conventional reforestation methods involving planting of tree seedlings, ANR offers significant cost advantages because it reduces or eliminates the costs associated with propagating, raising, and planting seedlings. It is most effectively utilized at the landscape level in restoring the protective functions of forests such as watershed protection and soil conservation. ANR techniques are flexible and allow for the integration of various values such as timber production, biodiversity recovery, and cultivation of crops, fruit trees, and non‐timber forest products in the restored forest. This paper describes the steps of applying ANR and conditions under which it will be most effective. It also discusses ANR’s comparative advantages as well as some of its constraints.     

Ecosystem Services and Opportunity Costs Shift Spatial Priorities for Conserving Forest Biodiversity

Inclusion of spatially explicit information on ecosystem services in conservation planning is a fairly new practice. This study analyses how the incorporation of ecosystem services as conservation features can affect conservation of forest biodiversity and how different opportunity cost constraints can change spatial priorities for conservation. We created spatially explicit cost-effective conservation scenarios for 59 forest biodiversity features and five ecosystem services in the county of Telemark (Norway) with the help of the heuristic optimisation planning software, Marxan with Zones. We combined a mix of conservation instruments where forestry is either completely (non-use zone) or partially restricted (partial use zone). Opportunity costs were measured in terms of foregone timber harvest, an important provisioning service in Telemark. Including a number of ecosystem services shifted priority conservation sites compared to a case where only biodiversity was considered, and increased the area of both the partial (+36.2%) and the non-use zone (+3.2%). Furthermore, opportunity costs increased (+6.6%), which suggests that ecosystem services may not be a side-benefit of biodiversity conservation in this area. Opportunity cost levels were systematically changed to analyse their effect on spatial conservation priorities. Conservation of biodiversity and ecosystem services trades off against timber harvest. Currently designated nature reserves and landscape protection areas achieve a very low proportion (9.1%) of the conservation targets we set in our scenario, which illustrates the high importance given to timber production at present. A trade-off curve indicated that large marginal increases in conservation target achievement are possible when the budget for conservation is increased. Forty percent of the maximum hypothetical opportunity costs would yield an average conservation target achievement of 79%.     

水稻害虫治理措施的综合评价

在对广州有机水稻生产示范区稻田节肢动物多样性和害虫控制效果调查分析的基础上,应用层次分析法对研究区有机水稻生产过程中经济、社会和生态3方面的效益和代价进行了评价.结果表明：有机水稻生产方式下所产生的综合效益最大,权重值达0.5355;生态代价在综合代价中占据主导地位;化学防治病虫害的水稻生产方式付出的生态代价最惨重,其综合代价权重值达0.6252;从综合效益代价比（RPC）来看,有机水稻生产模式是较理想的模式,其RPC值达2.4776,符合农业可持续发展的要求.     

Reconciling Biodiversity with Fishing: A Holistic Strategy for Pacific Sea Turtle Recovery

Recovery of sea turtle populations requires addressing: multiple sources of mortality; nonmarket, diffuse benefits with costs localized on the poor; and a transboundary resource with incomplete jurisprudence, markets, and institutions. Holistic recovery strategies include: beach conservation protecting nesting females, their eggs, and critical breeding habitat to maximize hatchling production; enhanced at-sea survival of turtles on the high seas and in commercial coastal fisheries; and reduced artisanal coastal fisheries mortality of turtles. The traditional approach of focusing long-term sustained conservation efforts on the nesting beaches has by itself led to increases in several sea turtle populations. However, current conservation is inadequate to reverse declines in other cases such as the critically endangered leatherback populations in the Pacific. This article discusses policy instruments comprising a holistic recovery strategy that reconciles fishing with biodiversity conservation.     

Land‐use strategies to balance livestock production,biodiversity conservation and carbon storage in Yucatán,Mexico

Balancing the production of food, particularly meat, with preserving biodiversity and maintaining ecosystem services is a major societal challenge. Research into the contrasting strategies of land sparing and land sharing has suggested that land sparing—combining high‐yield agriculture with the protection or restoration of natural habitats on nonfarmed land—will have lower environmental impacts than other strategies. Ecosystems with long histories of habitat disturbance, however, could be resilient to low‐yield agriculture and thus fare better under land sharing. Using a wider suite of species (birds, dung beetles and trees) and a wider range of livestock‐production systems than previous studies, we investigated the probable impacts of different land‐use strategies on biodiversity and aboveground carbon stocks in the Yucatán Peninsula, Mexico—a region with a long history of habitat disturbance. By modelling the production of multiple products from interdependent land uses, we found that land sparing would allow larger estimated populations of most species and larger carbon stocks to persist than would land sharing or any intermediate strategy. This result held across all agricultural production targets despite the history of disturbance and despite species richness in low‐ and medium‐yielding agriculture being not much lower than that in natural habitats. This highlights the importance, in evaluating the biodiversity impacts of land use, of measuring population densities of individual species, rather than simple species richness. The benefits of land sparing for both biodiversity and carbon storage suggest that safeguarding natural habitats for biodiversity protection and carbon storage alongside promoting areas of high‐yield cattle production would be desirable. However, delivering such landscapes will probably require the explicit linkage of livestock yield increases with habitat protection or restoration, as well as a deeper understanding of the long‐term sustainability of yields, and research into how other societal outcomes vary across land‐use strategies.     

Effects of Connectivity and Regional Dynamics on Restoration of Small Mammal Communities in Midwestern Grasslands

Grasslands are among the most imperiled North American ecosystems. State Acres for Wildlife Enhancement (SAFE) is a national conservation program that converts agricultural fields into grasslands mainly to improve habitat for high priority wildlife species. To provide a broader assessment of the contribution of the SAFE program to biodiversity in the Midwest region of North America, we evaluated local and landscape constraints to restoration of small mammal communities. We livetrapped small mammals during three summers (2009–2011) on plots that were recently seeded, seeded 1–4 years prior to sampling, or established references (>10 years old). Restoration trajectories for small mammal communities included a shift over time from dominance by the habitat generalist Peromyscus maniculatus (deer mouse) to communities dominated by grassland Microtus species (prairie voles and meadow voles). Vole abundance during the first year following restoration depended on spatial connectivity provided by linear habitats (roadside ditches and grass waterways) within 300 m of the restored grassland. Patch size and seeding type (cool‐season versus warm‐season grasses) were not predictors of early restoration success. In 2011, voles experienced a severe regional decline consistent with multi‐year population cycles. During the crash, most remaining voles occurred on restored SAFE grasslands, but not on established grasslands. This surprising outcome suggests young restoration plots could function as refuges for voles during population declines in agricultural landscapes.