ArticleLiterature Review
To read the full-text of this research, you can request a copy directly from the authors.

Abstract

Understanding how the world's flora and fauna will respond to bioenergy expansion is critical. This issue is particularly pronounced considering bioenergy's potential role as a driver of land-use change, the variety of production crops being considered and currently used for biomass, and the diversity of ecosystems that can potentially supply land for bioenergy across the planet. We conducted a global meta-analysis to ask how eight of the most commonly used bioenergy crops may impact site-level biodiversity. Species diversity and abundance were generally lower in crops being considered for bioenergy when compared to the natural ecosystems they may replace. First-generation crops, derived from oils, sugars, and starches, tended to have greater effects than second-generation crops, derived from lignocellulose, woody crops, or residues. Crop yield had non-linear effects on abundance and, to a lesser extent overall biodiversity, with biodiversity effects being driven by negative yield effects for birds but not other taxa. Our results emphasize that replacing natural ecosystems with bioenergy crops across the planet will largely be detrimental for biodiversity, with first generation and high yielding crops having the strongest negative effects. We argue that meeting energy goals with bioenergy using existing marginal lands or via biomass extraction within existing production landscapes may provide more biodiversity friendly alternatives than via land conversion of natural ecosystems. Impact Statement: Meta-analysis reveals that replacing natural ecosystems with bioenergy crops across the planet will largely be detrimental for biodiversity. This article is protected by copyright. All rights reserved.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the authors.

... The expansion and intensification of agricultural landuse has simplified landscape structure, and extended the use of chemical inputs, undermining biodiversity and other ecosystem functions [17]. Understanding the impact of expanded non-food bioenergy cropping on plant and animal species is crucial and previous qualitative reviews have identified both positive and negative impacts of these crops on biodiversity, depending on the reference land-use and land management [7,[18][19][20][21][22]. The conversion of natural and semi-natural ecosystems to non-food bioenergy crops is likely to lead to negative impacts on biodiversity [20,21,23], as well as the loss of stored carbon [12,13]. ...
... Understanding the impact of expanded non-food bioenergy cropping on plant and animal species is crucial and previous qualitative reviews have identified both positive and negative impacts of these crops on biodiversity, depending on the reference land-use and land management [7,[18][19][20][21][22]. The conversion of natural and semi-natural ecosystems to non-food bioenergy crops is likely to lead to negative impacts on biodiversity [20,21,23], as well as the loss of stored carbon [12,13]. Whilst it is often assumed that an expansion of non-food bioenergy crops will largely occur on marginal unimproved semi-natural land rather than productive agricultural land, this assumption is likely too simplistic. ...
... Currently, agricultural landscapes are typically intensively managed and often dominated by the monocultures of several crops, driving negative impacts on biodiversity [17]. Our results reflect the positive biodiversity impact that non-food bioenergy crops can have in these landscapes, through less intense management, increased heterogeneity, and providing features more similar to natural ecosystems [20,23,54,55]. The context of bioenergy planting will be important for determining biodiversity impacts locally, with management decisions, such as agrochemical inputs, weed control, tilling, vegetation structure, harvesting, and crop rotation all influencing outcomes [18][19][20]. ...
Article
Full-text available
Bioenergy has been identified as a key contributor to future energy scenarios consistent with the Paris Agreement targets, and is relied upon in scenarios both with and without bioenergy with carbon capture and storage, owing to the multiple ways in which bioenergy can substitute fossil fuels. Understanding the environmental and societal impacts of land-use change (LUC) to bioenergy crops is important in determining where and how they could be deployed, and the resulting trade-offs and co-benefits. We use systematic review and meta-analysis to assess the existing literature on two poorly understood impacts of this LUC that are likely to have an important effect on public acceptability: cultural ecosystem services and biodiversity. We focus on the impact of LUC to non-food bioenergy crops on agricultural landscapes, where large-scale bioenergy planting may be required. Our meta-analysis finds strong benefits for biodiversity overall (up 75% ± 13%), with particular benefits for bird abundance (+81% ± 32%), bird species richness (+100% ± 31%), arthropod abundance (+52% ± 36%), microbial biomass (+77% ± 24%), and plant species richness (+25% ± 22%), when land moves out of either arable crops or grassland to bioenergy production. Conversions from arable land to energy trees led to particularly strong benefits, providing an insight into how future LUC to non-food bioenergy crops could support biodiversity. There were inadequate data to complete a meta-analysis on the effects of non-food bioenergy crops on cultural ecosystem services, and few generalizable conclusions from a systematic review of the literature, however, findings highlight the importance of landscape context and planting strategies in determining impact. Our findings demonstrate improved farm-scale biodiversity on agricultural land with non-food bioenergy crops, but also limited knowledge concerning public response to this LUC, which could prove crucial to the successful expansion of bioenergy to meet the Paris targets.
... Because first-generation biofuels are generally higher-yielding than second-generation biofuels, they are thought to be more damaging to biodiversity, per unit area (Immerzeel et al. 2014;Núñez-Regueiro et al. 2020), and studies have reported that second-generation biofuels can have positive effects on aspects of biodiversity in temperate regions. For example, perennial grasses and short rotation coppiced willow have been found to diversify local vegetation structure and increase invertebrate abundance, which can provide food for birds and enhance avian diversity Haughton et al. 2016). ...
... However, most studies on biofuels and biodiversity are limited in taxonomic scope and are restricted to particular tropical or temperate regions (Dauber et al. 2010;Dornburg et al. 2010;Dauber and Miyake 2016). These limitations are problematic given that biodiversity impacts can vary among regions and taxonomic groups (Phillips et al. 2017;Núñez-Regueiro et al. 2020), and that long-distance biofuel trade poses a particular challenge to sustainability (Araújo et al. 2017). Synthesising studies from multiple geographic regions that investigate how a wide range of taxonomic groups are impacted by a variety of biofuel crops provides the best prospect for understanding some of these context-dependencies of the biofuel-biodiversity relationship, and for providing results that are robust enough to inform conservation and policy. ...
... Very few sources explicitly stated whether crops at each site were being grown for biofuel (only three out of 120 sources that were checked mentioned a biofuel term anywhere in the article). We therefore treated all sites with biofuel crops as biofuel sites, as in Fletcher et al. (2011) andNúñez-Regueiro et al. (2020), assuming that the biodiversity effects of growing the crop do not much depend on the crop's end use. Analysis of data from sites that are actually being used for biofuel would be preferable, and may produce ...
Article
Full-text available
Concerns about the impacts of climate change have led to increased targets for biofuel in the global energy market. First-generation biofuel crops contain oil, sugar or starch and are usually also grown for food, whereas second-generation biofuel is derived from non-food sources, including lignocellulosic crops, fast-growing trees, crop residues and waste. Biofuel production drives land-use change, a major cause of biodiversity loss, but there is limited knowledge of how different biofuel crops affect local biodiversity. Therefore, a more detailed understanding could inform more environmentally-conscious decisions about where to grow which biofuel crops. We synthesised data from 116 sources where a potential biofuel crop was grown and estimated how two measures of local biodiversity, species richness and total abundance, responded to different crops. Local species richness and abundance were 37% and 49% lower at sites planted with first-generation biofuel crops than in sites with primary vegetation. Soybean, wheat, maize and oil palm had the worst effects; the worst affected regions were Asia and Central and South America; and plant species richness and vertebrate abundance were the worst affected biodiversity measures. Second-generation biofuels had smaller, but still significant, effects: species richness and abundance were 19% and 25%, respectively, lower in such sites than in primary vegetation. Our models suggest that land clearance to cultivate biofuel crops reduces local biodiversity. However, the yield of biofuel from different crops influences the biodiversity impacts per unit of energy generated, and the geographic and taxonomic variation in effects are also relevant for making sustainable land-use decisions.
... Not all studies indicated standard errors and deviations. For this reason, the variance and weighting factors of the study-specific RRs were based on the number of locations (Hamman, Pappalardo, Bence, Peacor, & Osenberg, 2018;Núñez-Regueiro, Siddiqui, & Fletcher, 2019). The weighting factor W was calculated by Equation (2): where N PRG and N ara are the number of locations with PRG cultivation and annual arable crops respectively (Núñez-Regueiro et al., 2019). ...
... For this reason, the variance and weighting factors of the study-specific RRs were based on the number of locations (Hamman, Pappalardo, Bence, Peacor, & Osenberg, 2018;Núñez-Regueiro, Siddiqui, & Fletcher, 2019). The weighting factor W was calculated by Equation (2): where N PRG and N ara are the number of locations with PRG cultivation and annual arable crops respectively (Núñez-Regueiro et al., 2019). The mean weighted response ratio (RR ++ ) was calculated from the RRs of individual pairwise comparisons between PRG and the reference, as given in Equation (3): ...
... The first category is related to information on biomass yield, which predominantly depends on climate and soil conditions but also on factors including planting density, crop establishment status, plant age and genotypic variation. As has been previously shown, these attributes strongly influence biodiversity potential in second-generation biomass crops and PRGs in particular (Dauber et al., 2015;Núñez-Regueiro et al., 2019). Biomass productivity is directly F I G U R E 2 Cumulated response of biodiversity impacts to cultivation of perennial rhizomatous grasses (PRG). ...
Article
Full-text available
Perennial rhizomatous grasses (PRG), such as miscanthus and switchgrass, are considered promising lignocellulosic feedstocks. Their cultivation is expected to experience a significant increase in the near future, as it offers a wide range of benefits. For instance, when PRG replace typical annual crops, positive biodiversity impacts are usually anticipated. However, to date, there is no solid, statistically strong evidence for this hypothesis. This study aims to evaluate its validity through a meta‐analysis based on an extensive systematic literature review of research comparing biodiversity attributes in PRG and common annual crops. Dynamics of species richness and abundance in response to PRG cultivation were quantitatively evaluated drawing on 220 paired comparisons from 25 studies. This includes data on five taxonomic groups—arthropods, birds, earthworms, mammals and plants—and three PRG—miscanthus, switchgrass and reed canary grass. The results indicate that biodiversity tends to be higher in PRG cultivations relative to the reference crops, but the initial hypothesis of significantly beneficial impacts could not be confirmed. Trends were specific to the individual taxonomic groups: significantly higher biodiversity was found for plants and small mammals. Positive but insignificant trends were observed for arthropods and birds, while earthworm response was neutral and insignificant. More substantial conclusions could not be drawn, which is mainly due to the low number of studies conducting biodiversity assessments in PRG cultivations that included a comparison with annual crops. In addition, a detailed analysis of the observed responses was impaired by poor reporting of the parameters influencing biodiversity in the studies reviewed, such as planting and crop density, as well as yields. For this reason, we conclude with a call for improved data reporting in biodiversity assessments of PRG cultivations and detail requirements for future biodiversity research.
... LUC represents the major driver of biodiversity loss in recent decades, with 47 % of natural ecosystems in decline and around one million plant and animal species estimated to be at risk of extinction 16 . Understanding the impact of expanded bioenergy cropping on different species is crucial and previous qualitative reviews have identified both positive and negative impacts of bioenergy crop deployment on biodiversity, depending on the reference land-use and land management 7,[17][18][19][20] . The conversion of natural and semi-natural ecosystems to bioenergy crops is likely to lead to negative impacts on biodiversity 19,20 , as well as the loss of stored carbon 12,13 . ...
... Understanding the impact of expanded bioenergy cropping on different species is crucial and previous qualitative reviews have identified both positive and negative impacts of bioenergy crop deployment on biodiversity, depending on the reference land-use and land management 7,[17][18][19][20] . The conversion of natural and semi-natural ecosystems to bioenergy crops is likely to lead to negative impacts on biodiversity 19,20 , as well as the loss of stored carbon 12,13 . It is often assumed that an expansion of bioenergy crops will largely occur on marginal unimproved semi-natural land rather than productive agricultural land, but this assumption is likely too simplistic. ...
... ; https://doi.org/10.1101/2021.06.16.448590 doi: bioRxiv preprint ecosystem services 53 . Future improved crop yields and dietary shifts away from animal agriculture could free up agricultural land for conversion to bioenergy crops, supporting biodiversity without undermining food security and could be an attractive way to expand bioenergy cropping, given that a recent review found evidence that LUC from natural ecosystems to bioenergy crops could be negative for biodiversity 19 . ...
Preprint
Full-text available
Most decarbonization scenarios of energy systems necessitate more than 500 Mha of land converted to non-food bioenergy crops to provide both energy substitutes for fossil fuels and negative emissions through bioenergy with carbon capture and storage (BECCS). Understanding the environmental and societal impact of this significant land-use change (LUC) is important in determining where and how bioenergy crops should be deployed, and the trade-offs and co-benefits to the environment and society. Here, we use two systematic reviews and a meta-analysis to assess the existing literature on impacts that are likely to have an important effect on public perceptions of the acceptability of such land use change: biodiversity and amenity value. We focus on the impact of LUC to non-food bioenergy crops on agricultural landscapes, where large-scale bioenergy planting may be required. Our meta-analysis finds strong benefits for biodiversity overall (up 75 % ± 13 %), with particular benefits for bird abundance (+ 81 % ± 32 %), bird species richness (+ 100 % ± 31 %), arthropod abundance (+ 52 % ± 36 %), microbial biomass (+ 77 % ± 24 %), and plant species richness (+ 25 % ± 22 %), when land moves out of either arable crops or grassland to bioenergy production. Conversions from arable land to energy trees led to particularly strong benefits, providing an insight into how future LUC to bioenergy crops could support biodiversity. There were inadequate data to complete a meta-analysis on the effects of bioenergy crops on landscape amenity value, and few generalizable conclusions from systematic review of the literature, however, findings highlight the importance of landscape context and planting strategies in determining amenity values. Our findings demonstrate improved farm-scale biodiversity on agricultural land with bioenergy crops, but also limited knowledge concerning public response to this land use change which could prove crucial to the effective deployment of bioenergy.
... Introduction of the moldboard plough for breaking up native prairies catalysed the almost complete conversion of these ecosystems in the Midwest to crops (Bogue, 2011;Smith, 1981). Further west, the invention of barbed wire to control cattle was instrumental in bringing agricultural activity to the Great Plains during the late 19th century (Netz, 2004). This westward expansion, combined with industrialization in the east, contributed to a "forest transition" in New England, where widespread abandonment of agricultural land and reforestation occurred (Mather, 1992). ...
... These feedstocks could range from annual crops like corn and sorghum to herbaceous perennial grasses like switchgrass and Miscanthus and woody species like poplar and pine. While turning to corn as a bioenergy feedstock exacerbates landscape simplification and further erodes ecosystem services (Landis et al., 2008), perennial crops tend to be more friendly to biodiversity (Núñez-Regueiro et al., 2020;Werling et al., 2014). Replacing annual crops with perennial bioenergy grasslands could strongly enhance ecosystem services Robertson et al., 2017;Werling et al., 2014). ...
Chapter
Agricultural landscapes in North America have developed through complex interactions of biophysical, socioeconomic and technological forces. While they can be highly productive, these landscapes are increasingly simplified, causing biodiversity loss. As a result, ecosystem services associated with biodiversity are being dismantled. Agricultural landscape structure arises from collective decisions of farmers over long time periods, which are usually not intentionally coordinated beyond the farm scale. Regaining ecosystem services will require active efforts to intentionally redesign landscapes, in part based on ecological evidence about relationships between landscape structure and ecosystem services. Here we focus on services provided by arthropods and how to foster them at landscape scales. We first provide a brief history of how agricultural landscape structure in temperate North America developed and review the landscape-scale ecological drivers underpinning arthropod-based ecosystem services. We then propose ecological and social principles for designing agricultural landscapes, based on the ecological evidence we reviewed and on previous efforts in agricultural landscape design. Finally, we look ahead to discern prospects for putting agricultural landscape design into practice, including ecological, technological and policy opportunities. To reap benefits from arthropod-based services, future agricultural landscapes will need to increase in structural heterogeneity and diversity across multiple dimensions including crop, farmer and consumer diversity. A number of knowledge gaps persist, including how to design landscapes at spatial scales that are relevant to service providers, identifying areas of overlap or conflict between design for ecosystem services and for biodiversity conservation more broadly and navigating the social and political processes needed to implement landscape design.
... Introduced species such as Miscanthus sp. have the ability to become invasive [8][9][10] creating other environmental issues. Annual crops, such as maize, take more effort and resources to establish every year and provide fewer ecosystem services compared with perennials, including increased runoff, nutrient loss, and soil erosion [11][12][13][14][15]. Native perennial biofuels perform better than annual biofuels in terms of positively impacting wildlife, however, if native habitat was removed to plant the perennial biofuel wildlife may be negatively impacted [16][17][18][19]. The type of biofuels and location on the landscape are vital components to successful biofuel plantings, as ecosystem services and wildlife benefit from native perennial plants in the right settings [14,[20][21][22]. ...
... Literature search results showed eighteen papers saying that either diversity, abundance, richness, or presence of insects, birds, and other vertebrates were positively impacted by having native perennial biofuels planted [8,[14][15][16][17][18][19]21,22,[77][78][79][80][81][82][83][84][85]. The differences between how the wildlife reacted to native perennial biofuels depended on what the previous land use was, which perennial biofuel was planted, and biofuel harvest dates. ...
Article
Full-text available
While biofuels have been touted as a benefit for growers—with the ability to be planted on marginal lands, for improved wildlife habitat, to sustain soils, and to reduce runoff—there remains to be a general summary of how beneficial they really are. This paper aims to review the environmental effects, feasibility, and economic aspects of using native perennial grasses in North America as biofuels as opposed to traditional annual crops. The Scopus database was used to search for manuscripts relating to each topic. In some instances, very few results appeared, so a second database, Digitop, was also used. Native perennial grasses have been found to sequester carbon and cultivating them can create a carbon sink in the soil. Overall, wildlife benefit more by having native perennial grass for biofuels planted than annual maize and having fewer harvests a season is better for wildlife over the entire year. Economically, growing native perennial grasses can be advantageous especially on marginal land, where it has a comparatively high yield. Although the second-generation biofuel supply chain is susceptible to changing market prices, it can be made more resilient and has advantages, for example resistance against the impacts of drought. Although there are many cultivars to choose from, factors like climate, soil, and genetics can provide pertinent information to match each specimen’s ideal growing conditions to the right location.
... One method of landscape diversification is to convert marginal lands-lands that are under cultivation but consistently underperforming (Basso et al., 2019)-to natural or seminatural habitats that can also produce bioenergy (Cai et al., 2011;Núñez-Regueiro et al., 2019;Robertson et al., 2008). Biofuel agriculture is needed in most climate mitigation scenarios that limit atmospheric warming to 1.5°C by 2100 due to its ability to reduce life cycle carbon emissions (Gelfand et al., 2020;IPCC, 2018). ...
Article
Full-text available
In order to both combat the decline of biodiversity and produce food, fuel, and fiber for a growing human population, current agricultural landscapes must transition into diversified, multifunctional systems. Perennial cellulosic biofuel crops have potential to meet both of these challenges, acting as multifunctional systems that can enhance biodiversity. What is not well understood, and what we test here, are the trade‐offs among different perennial crops in their performance as biofuels and in biodiversity conservation. Working in an established bioenergy experiment with four native, perennial, cellulosic biofuel crop varieties – ranging from monoculture to diverse restoration planting – we tested the effect of biofuel crop management on flower communities, pollinator communities, and crop yield. The greatest abundance and diversity of pollinators and flowers were in treatments that were successional (unmanaged), followed by restored prairie (seeded mix of native grasses and forbs), switchgrass, and a mix of native grasses. However, biofuel crop yield was approximately the inverse, with native grasses having the highest yield, followed by switchgrass and prairie, then successional treatments. Restored prairie was the optimal biofuel crop when both pollinator conservation and crop yield are valued similarly. We add to mounting evidence that policy is needed to create sustainable markets that value the multifunctionality of perennial biofuel systems in order to achieve greater ecosystem services from agricultural landscapes.
... There is still a lack of agreement on the degree to which biofuels both provide positive ecosystem services (e.g., fuel, climate regulation) and compromise other ecosystem services (e.g., biodiversity, food) (Fischer et al., 2009). Perhaps the most controversial are precisely the first generation biofuels, i.e. bioethanol and biodiesel from dedicated crops, because several studies have confirmed their negative impact on the environment (Kaletnik et al., 2019), biodiversity (Núñez-Regueiro et al., 2019), climate (Frank et al., 2016) and food prices (Chakravorty et al., 2017). Land and resource constraints create economic pressure among the various anthropogenic uses of biomass, the so called food-energy-environment trilemma (Wang et al., 2017). ...
Article
Agro-ecosystems have large potentials for supporting human well-being and local development, also by providing large amounts of organic matter for bioenergy generation. The use of agricultural residues was proposed as a possible solution to support energy transition, while avoiding conflicts for the use of agricultural land destined to food production. The present work uses an Ecosystem Services (ES) approach to map and estimate the potential availability of agricultural residues (potential ES supply) in the Emilia-Romagna region (Italy), where high productive croplands are present. The map was overlapped with the bioenergy plants currently present in the region (ES demand) that could be sustained by residues, considering a buffer area of 10 km radius for a sustainable supply chain and under the assumption of using only the 25% of total residues. Additionally, suitable areas for bioenergy development were mapped by means of a hotspot analysis. The results showed that the Emilia-Romagna region has a large availability of agricultural residues to be potentially used for bioenergy generation. The 82.4% of the total installed power of biogas plants and the whole installed power of those using woody biomasses may be supported by using agricultural residues. When considering buffer areas for sustainable supply chains, agricultural residues could meet the 95% and 50% of total demand from biogas and solid biomasses plants, respectively. However, competition for agricultural residues among bioenergy plants could arise because of the overlap of their buffer zones. Moreover, hotspot analysis revealed large suitable areas for the development of environmental and cost-effective biogas plants. Contrasting ES supply and demand may unveil unexplored forms of sustainable development in agro-ecosystems, thus contributing to a more rational use of agricultural production which supports renewable energies without competing for the agricultural land.
... In the southeastern United States, agricultural land use conversions for bioenergy production are expected to come mostly in the form of loblolly pine plantations (U.S. Department of Energy, 2016;Núñez-Regueiro et al., 2021;Perdue et al., 2017;USDA 2010). Pine plantation owners have responded to these changing energy standards and have increased profits by overseeing a variety of factors ranging from fertilization rates to physical site characteristics (Trlica et al., 2021;Vance et al., 2010). ...
Article
Full-text available
Changes in global bioenergy consumption have catalyzed the emergence of forest plantations as an important energy alternative. In the southeastern United States, land cover changes caused by increasing demands for pine trees as a bioenergy feedstock incite associated impacts on local ecosystem services (e.g., water yield). However, water yield impacts from pine plantation management strategies, such as thinning and short rotation, have yet to be simultaneously examined on multiple spatial scales. Here, we modeled the effects of thinning and clear-cut conditions on long term mean annual water yield across a 55-year time horizon at the watershed scale (watershed area ranging 696 – 7,374 km²) in northern Florida, southern Georgia, and southern Alabama. Additionally, we assessed the long term water yield effects of thinning, clear-cut, and short-rotation management at the pine plantation (i.e., plot) scale. We compared three plot-level evapotranspiration models as well as the watershed-level Water Supply Stress Index water balance model to simulate plot and watershed hydrologic responses from pine plantation management scenarios. Both methods showed that 10% thinning had the smallest increase in water yield (<6%), while clear-cut conditions imposed the greatest increase (up to 51% for plot scale and up to 25% for watershed scale simulations). Short-rotation management caused plot-level water yield increases ranging from 3% to 24%. Overall, greater water yield effects were seen in site simulations, rather than in watersheds, reinforcing the importance of scale when assessing water budget impacts given land cover changes. These results suggest that landowners have agency over the magnitude of water that is yielded from their plantations and that local water supply shortages can be mitigated by changing forestry biomass management strategies. The opportunity to supplement local water availability is especially valuable within the context of changing climate cycles that may bring about drier local conditions. The multi-scale approach presented here can support efforts from landowners and water managers to optimize profit as well as ecosystem service provision.
... Thus, biomass could be a sustainable alternative as long as this approach focuses, for example, on the use of waste, circular economy, and processes without extensive land use. 91 On the other hand, in Chile, geothermal energy development is still early; nevertheless, the country is a pioneer in South America. 92 Note that an energy democracy agenda that seeks to promote far-reaching participation through jointly planned public and communitarian property 93 is a topic that has not yet been fully explored and implemented in the Global South. ...
Article
Addressing climate change is one of the main challenges of twenty-first-century societies. In this context, the energy sector can contribute significantly to the reduction of anthropogenic emissions. Thus, global policies have focused on energy efficiency and the transition to non-conventional renewable energy sources. Still, unfortunately, these topics are often undeveloped and unstudied in countries of the Global South. In a tentative to fill this gap, this article focuses on the transition of the Chilean and Brazilian electrical systems. Notably, both countries have historically used hydro- and thermoelectricity as their predominant energy sources but introducing new resources in the latest years. Thus, this work aimed to analyze the creation and articulation of specific political–institutional arrangements to promote the energy matrix diversification from the beginning of this century and their possible effects on the energy transition process. Despite differences in their paths, the cases analyzed present common elements, such as the crises as triggers and the implementation of energy policy packages since the 2000s decade.
... Additionally, perennial grasses require less intensive management and fewer chemical inputs than their first-generation counterparts to achieve economically viable yields, providing numerous environmental benefits such as reduced nitrogen (N) leaching and greenhouse gas emissions . There is also growing evidence that perennial grass bioenergy cropping systems (PGCS) promote greater biodiversity and ecosystem services, such as increased pollinator abundance and biological pest suppression, than annual, more intensively managed systems (Bellamy et al., 2009;Landis et al., 2018;Meehan et al., 2012;Núñez-Regueiro et al., 2021;Robertson et al., 2012;Werling et al., 2014). A final prominent advantage is the expectation that PGCS have greater potential to accrue and store soil organic C (SOC) (Anderson-Teixeira et al., 2009;Fargione et al., 2008;McGowan et al., 2019). ...
Article
Full-text available
Perennial grass energy crop production is necessary for the successful and sustainable expansion of bioenergy in North America. Numerous environmental advantages are associated with perennial grass cropping systems, including their potential to promote soil carbon accrual. Despite growing research interest in the abiotic and biotic factors driving soil carbon cycling within perennial grass cropping systems, soil fauna remain a critical yet largely unexplored component of these ecosystems. By regulating microbial activity and organic matter decomposition dynamics, soil fauna influence soil carbon stability with potentially significant implications for soil carbon accrual. We begin by reviewing the diverse, predominantly indirect effects of soil fauna on soil carbon dynamics in the context of perennial grass cropping systems. Since the impacts of perennial grass energy crop production on soil fauna will mediate their potential contributions to soil carbon accrual, we then discuss how perennial grass energy crop traits, diversity, and management influence soil fauna community structure and activity. We assert that continued research into the interactions of soil fauna, microbes, and organic matter will be important for advancing our understanding of soil carbon dynamics in perennial grass cropping systems. Further, explicit consideration of soil faunal effects on soil carbon can improve our ability to predict changes in soil carbon following perennial grass cropping system establishment. We conclude by addressing the major knowledge gaps that should be prioritized to better understand and model the complex connections between perennial grass bioenergy systems, soil fauna, and carbon accrual.
... 7 Figure 1. Worldwide bioenergy production prospect [11]. Despite the broad interest in bioenergy and its inclusion in future scenarios, it is still faced with various challenges. ...
Article
Full-text available
The concerns about increasing greenhouse gas emissions and climate change have mobilized the world towards using new materials and technologies to decarbonize the global economy. In line with this, the utilization of diverse forms of bioenergy is expected to expand in various economic sectors due to their potential to solve environmental concerns. More specifically, the carbon contained in bioenergy is mainly from biogenic carbon dioxide; thus, bioenergy utilization contributes much less to environmental impacts than fossil energy. Despite the renewability of bioenergy sources, their production is dependent on immense amounts of construction materials, chemicals, and, most importantly, energy resources. Since the production and use of the above items are also responsible for environmental problems and challenges, the sustainability of bioenergy product systems might also be questioned. Life cycle assessment is a powerful tool to quantify the environmental sustainability of various products, including bioenergy production. It also can identify the sources and causes of the environmental impacts of bioenergy product systems. Despite the significant advantages of life cycle assessment in assessing the environmental sustainability of bioenergy product systems, there are still limitations and disadvantages to using this method. Different assumptions, various inventory data, different methods of impact assessment, and many other sources of uncertainty may give rise to wide ranges of final results. These issues can negatively affect the accuracy and reliability of bioenergy product systems’ life cycle assessment results, leading to incorrect decisions and policies. In light of the above, this study critically discusses the pros and cons of life cycle assessment in bioenergy product systems, identifying the gaps and sources of uncertainty. Finally, frameworks and procedures to improve the applicability and validity of life cycle assessment are suggested to shed light on future research directions.
... A shift to bioenergy production may entail intensification that differs from traditional timber practices to supply wood fiber. These changes could include shortening stand rotation times, planting at higher densities, planting faster-growing tree species, and land conversion, each of which could result in negative impacts to native ecosystems (Aguilar et al., 2020) and biodiversity (Fletcher et al., 2011;Nuñez-Regueiro et al., 2021). Concerns about the sustainability and carbon neutrality of wood-based biomass production have resulted in the UK and EU mandating that such production meets sustainability standards along the supply chain (i.e., carbon neutrality, reforestation after wood harvest, protection of biodiversity, and compliance with best management practices to maintain environmental quality [e.g., water or soil quality]) (Dale et al., 2016;Hodges et al., 2019;Kittler et al., 2020). ...
Article
Full-text available
International demand for wood and other forest products continues to grow rapidly, and uncertainties remain about how animal communities will respond to intensifying resource extraction associated with woody bioenergy production. We examined changes in alpha and beta diversity of bats, bees, birds, and reptiles across wood production landscapes in the southeastern United States, a biodiversity hotspot that is one of the principal sources of woody biomass globally. We sampled across a spatial gradient of paired forest land-uses (representing pre and postharvest) that allowed us to evaluate biological community changes resulting from several types of biomass harvest. Short-rotation practices and residue removal following clearcuts were associated with reduced alpha diversity (-14.1 and -13.9 species, respectively) and lower beta diversity (i.e., Jaccard dissimilarity) between land-use pairs (0.46 and 0.50, respectively), whereas midrotation thinning increased alpha (+3.5 species) and beta diversity (0.59). Over the course of a stand rotation in a single location, biomass harvesting generally led to less biodiversity. Cross-taxa responses to resource extraction were poorly predicted by alpha diversity: correlations in responses between taxonomic groups were highly variable (-0.2 to 0.4) with large uncertainties. In contrast, beta diversity patterns were highly consistent and predictable across taxa, where correlations in responses between taxonomic groups were all positive (0.05-0.4) with more narrow uncertainties. Beta diversity may, therefore, be a more reliable and information-rich indicator than alpha diversity in understanding animal community response to landscape change. Patterns in beta diversity were primarily driven by turnover instead of species loss or gain, indicating that wood extraction generates habitats that support different biological communities.
... In addition, it is recognized that utilizing marginal lands for perennial crop production can have advantageous effects on biodiversity and contribute to land restoration [16]. For example, utilizing marginal lands to produce perennials can enhance biodiversity (SDG 15) by avoiding directly or indirectly the conversion of natural ecosystems for bioenergy production [120]. Furthermore, compared to annual crops, perennial crops can sequester more carbon in biomass and soil, improve soil quality, and reduce soil erosion (SDG 15.3) [121,122]. ...
Article
Full-text available
Bioenergy aims to reduce greenhouse gas (GHG) emissions and contribute to meeting global climate change mitigation targets. Nevertheless, several sustainability concerns are associated with bioenergy, especially related to the impacts of using land for dedicated energy crop production. Cultivating energy crops can result in synergies or trade-offs between GHG emission reductions and other sustainability effects depending on context-specific conditions. Using the United Nations Sustainable Development Goals (SDGs) framework, the main synergies and trade-offs associated with land use for dedicated energy crop production were identified. Furthermore, the context-specific conditions (i.e., biomass feedstock, previous land use, climate, soil type and agricultural management) which affect those synergies and trade-offs were also identified. The most recent literature was reviewed and a pairwise comparison between GHG emission reduction (SDG 13) and other SDGs was carried out. A total of 427 observations were classified as either synergy (170), trade-off (176), or no effect (81). Most synergies with environmentally-related SDGs, such as water quality and biodiversity conservation, were observed when perennial crops were produced on arable land, pasture or marginal land in the ‘cool temperate moist’ climate zone and ‘high activity clay’ soils. Most trade-offs were related to food security and water availability. Previous land use and feedstock type are more impactful in determining synergies and trade-offs than climatic zone and soil type. This study highlights the importance of considering context-specific conditions in evaluating synergies and trade-offs and their relevance for developing appropriate policies and practices to meet worldwide demand for bioenergy in a sustainable manner.
... Supplanting regular biological systems with bioenergy crops across the planet will generally be unfavorable for biodiversity, with first-generation and high-yield crops having the most grounded adverse consequences. Meeting energy objectives with bioenergy utilizing existing negligible grounds or biomass extraction inside existing development landscapes might give more biodiversity-accommodating options than changing typical biological systems for biofuel generation (Núñez-Regueiro et al. 2021). ...
Article
Full-text available
This review gives concise information on green technology (GT) and Industrial Revolution 4.0 (IR 4.0). Climate change has begun showing its impacts on the environment, and the change is real. The devastating COVID-19 pandemic has negatively affected lives and the world from the deadly consequences at a social, economic, and environmental level. In order to balance this crisis, there is a need to transition toward green, sustainable forms of living and practices. We need green innovative technologies (GTI) and Internet of Things (IoT) technologies to develop green, durable, biodegradable, and eco-friendly products for a sustainable future. GTI encompasses all innovations that contribute to developing significant products, services, or processes that lower environmental harm, impact, and worsening while augmenting natural resource utilization. Sensors are typically used in IoT environmental monitoring applications to aid ecological safety by nursing air or water quality, atmospheric or soil conditions, and even monitoring species’ movements and habitats. The industries and the governments are working together, have come up with solutions—the Green New Deal, carbon pricing, use of bio-based products as biopesticides, in biopharmaceuticals, green building materials, bio-based membrane filters for removing pollutants, bioenergy, biofuels and are essential for the green recovery of world economies. Environmental biotechnology, Green Chemical Engineering, more bio-based materials to separate pollutants, and product engineering of advanced materials and environmental economies are discussed here to pave the way toward the Sustainable Development Goals (SDGs) set by the UN and achieve the much-needed IR 4.0 for a greener-balanced environment and a sustainable future. Graphical abstract
... In the southeastern United States, agricultural land use conversions for bioenergy production are expected to come mostly in the form of loblolly pine plantations (U.S. Department of Energy, 2016;Núñez-Regueiro et al., 2021;Perdue et al., 2017;USDA 2010). Pine plantation owners have responded to these changing energy standards and have increased profits by overseeing a variety of factors ranging from fertilization rates to physical site characteristics (Trlica et al., 2021;Vance et al., 2010). ...
... Third, pine plantations in the Southeast are typically thinned (i.e., tree density is reduced for the first time commercially between ages 12 and 16 to promote growth of remaining trees; Antony et al. 2011, Amateis andCarlson 2014), and this harvested material is a potential source of biomass for bioenergy production. The energy yield obtained from each of these three biomass production pathways varies (Eisenbies et al. 2009, Munsell andFox 2010), and the nature of their impacts on biodiversity is presumed to vary as well (Verschuyl et al. 2011, Riffell et al. 2011a,b, Gottlieb et al. 2017, Loy et al. 2020, Nuñez-Regueiro et al. 2020. ...
Article
Full-text available
Human demand for food, fiber, and space is accelerating the rate of change of land cover and land use. Much of the world now consists of a matrix of natural forests, managed forests, agricultural cropland, and urbanized plots. Expansion of domestic energy production efforts in the USA is one driver predicted to influence future land‐use and land management practices across large spatial scales. Favorable growing conditions make the southeastern USA an ideal location for producing a large portion of the country’s renewable bioenergy. We investigated patterns of bat occurrence in two bioenergy feedstocks commonly grown in this region (corn, Zea mays, and pine, Pinus taeda and P. elliottii). We also evaluated potential impacts of the three major pathways of woody biomass extraction (residue removal following clearcut harvest, short‐rotation energy plantations, and mid‐rotation forest thinning) to bat occurrence through a priori land‐use contrasts. We acoustically sampled bat vocalizations at 84 sites in the Southeastern Plains and Southern Coastal Plains of the southeastern USA across three years. We found that mid‐rotation thinning resulted in positive effects on bat occurrence, and potential conversion of unmanaged (reference) forest to managed forest for timber and/or bioenergy harvest resulted in negative effects on bat occurrence when effects were averaged across all species. The effects of short‐rotation energy plantations, removal of logging residues from plantation clearcuts, and corn were equivocal for all bat species examined. Our results suggest that accelerated production of biomass for energy production through either corn or intensively managed pine forests is not likely to have an adverse effect on bat communities, so long as existing older unmanaged forests are not converted to managed bioenergy or timber plantations. Beyond bioenergy crop production, mid‐rotation thinning of even‐aged pine stands intended for timber production, increases to the duration of plantation rotations to promote older forest stands, arranging forest stands and crop fields to maximize edge habitat, and maintaining unmanaged forests could benefit bat communities by augmenting roosting and foraging opportunities.
Article
The purpose of this paper is to investigate the perspective of using wood waste, especially the one that resulted from the construction and demolition activities, to produce sustainable bioenergy. The context of this research is characterized by a more accelerated need for development, a growing need for energy to fuel all human activities, and a greater awareness of the pressure on the environment and the negative effects produced. One of the major challenges for environmental protection is the issue of mitigating CO2 emissions, and among the biggest contributors to the CO2 emissions is the construction industry. Given the current rhythm of society development, a decrease in construction activities is not possible so a solution can be better management of the waste produced in various stages. If the need for better waste management is joined with the need for more sustainable energy, then using waste to produce bioenergy seems like a good solution. This study focuses mainly on wood waste and to respond to the research purpose it uses bibliometric literature search, scientometric analysis, and in‐depth discussions. The data were obtained by interrogating the ISI Web of Science database using the keywords “bioenergy”, “wood waste” and “construction and demolition” as search criteria. The extraction of data was done using the PRISMA method and processed with VOSviewer and Bibliometrix software. The processing of the data was done so to obtain information related to the importance of the research topic given by the number of publications, the most studied topics revealed by a keywords co‐occurrence analysis and a trend topic plot, as well as the world scientific productions on the studied topics. The main results indicate a significant increase, in the last years, of the interest in the studied topics, all over the world. Wood waste is considered as a direct combustion fuel or as a raw material for components of fuels used to produce energy, as well as components for new building materials. Given the limitations of other renewable energy sources, wood biomass is a subject that must be considered more in the future. The use of wood waste as biomass for the production of bioenergy can be a very good solution that will bring the advantage of both ensuring a renewable source of energy and at the same time decreasing the impact of the building industry on the environment. This paper investigates the perspective of using wood waste from construction and demolition to produce sustainable bioenergy. Based on a bibliometric analysis of the data extracted from the ISI web of science database was observed an increased interest in this topic in recent years and that the use of wood waste can be very good solution to ensure a renewable source of energy and to decrease the impact of the building industry on the environment.
Article
Switchgrass has been identified as a high potential bioenergy feedstock, and was expected to play an important role in achieving the production targets for cellulosic biofuels laid out under the Energy Security and Independence Act of 2007. However, the development of cellulosic biofuels at commercially viable levels has been slower than anticipated and supply side challenges, due to limited feedstock availability, continue to be a major bottleneck. Understanding the role of the farming community, their perceptions, and their willingness to cultivate dedicated bioenergy feedstocks is an important part of overcoming these challenges. To this end, a survey was administered in March-April 2017 and the results of our analysis are both insightful and timely. We studied the role of farmer perceptions around the suitability of switchgrass for their operations. We evaluated the impact of their perceptions and existing land uses on their willingness to cultivate switchgrass and their land allocation decisions using a 2-step Heckman model. Factors such as potential for diversification of crop-mix, creation of habitat for wildlife, as well as ownership of woodland or forestland played an important role in influencing farmer willingness to cultivate switchgrass. We also found that land allocated for switchgrass cultivation was more likely to come from lands under non-crop uses, such as hay or other land use, and was unlikely to cause displacement of lands used for cultivating row crops, which obviates conflicts that could arise from competing land use vis-à-vis food-crops.
Article
Full-text available
Bioenergy with carbon capture and storage (BECCS) based on purpose-grown lignocellulosic crops can provide negative CO2 emissions to mitigate climate change, but its land requirements present a threat to biodiversity. Here, we analyse the implications of crop-based BECCS for global terrestrial vertebrate species richness, considering both the land-use change (LUC) required for BECCS and the climate change prevented by BECCS. LUC impacts are determined using global-equivalent, species-area relationship-based loss factors. We find that sequestering 0.5–5 Gtonne of CO2 per year with lignocellulosic crop-based BECCS would require hundreds of Mha of land, and commit tens of terrestrial vertebrate species to extinction. Species loss per unit of negative emissions decreases with: i) longer lifetimes of BECCS systems, ii) less overall deployment of crop-based BECCS, and iii) optimal land allocation, i.e., prioritising locations with lowest species loss per negative emission potential, rather than minimising overall land use or prioritising locations with lowest biodiversity. The consequences of prevented climate change for biodiversity are based on existing climate response relationships. Our tentative comparison shows that for crop-based BECCS considered over 30 years, LUC impacts on vertebrate species richness may outweigh the positive effects of prevented climate change. Conversely, for BECCS considered over 80 years, the positive effects of climate change mitigation on biodiversity may outweigh the negative effects of LUC. However, both effects and their interaction are highly uncertain and require further understanding, along with analysis of additional species groups and biodiversity metrics. We conclude that factoring in biodiversity means lignocellulosic crop-based BECCS should be used early to achieve the required mitigation over longer time periods, on optimal biomass cultivation locations, and most importantly, as little as possible where conversion of natural land is involved, looking instead to sustainably grown or residual biomass-based feedstocks and alternative strategies for carbon dioxide removal.
Article
Full-text available
The type of metric and weighting method used in meta-analysis can create bias and alter coverage of confidence intervals when the estimated effect size and its weight are correlated. Here, we investigate bias associated with the common metric, Hedges’d, under conditions common in ecological meta-analyses. We simulated data from experiments, computed effect sizes and their variances, and performed meta-analyses applying three weighting schemes (inverse variance, sample size, and unweighted) for varying levels of effect size, within-study replication, number of studies in the meta-analysis, and among-study variance. Unweighted analyses, and those using weights based on sample size, were close to unbiased and yielded coverages close to the nominal level of 0.95. In contrast, the inverse-variance weighting scheme led to bias and low coverage, especially for meta-analyses based on studies with low replication. This bias arose because of a correlation between the estimated effect and its weight when using the inverse-variance method. In many cases, the sample size weighting scheme was most efficient, and, when not, the differences in efficiency among the three methods were relatively minor. Thus, if using Hedges’d, we recommend using weights based upon sample size that do not involve individual study estimates of the effect size.
Article
Full-text available
The idea that noncrop habitat enhances pest control and represents a win-win opportunity to conserve biodiversity and bolster yields has emerged as an agroecological paradigm. However, while noncrop habitat in landscapes surrounding farms sometimes benefits pest predators, natural enemy responses remain heterogeneous across studies and effects on pests are inconclusive. The observed heterogeneity in species responses to noncrop habitat may be biological in origin or could result from variation in how habitat and biocontrol are measured. Here, we use a pest-control database encompassing 132 studies and 6,759 sites worldwide to model natural enemy and pest abundances, predation rates, and crop damage as a function of landscape composition. Our results showed that although landscape composition explained significant variation within studies, pest and enemy abundances, predation rates, crop damage, and yields each exhibited different responses across studies, sometimes increasing and sometimes decreasing in landscapes with more noncrop habitat but overall showing no consistent trend. Thus, models that used landscape-composition variables to predict pest-control dynamics demonstrated little potential to explain variation across studies, though prediction did improve when comparing studies with similar crop and landscape features. Overall, our work shows that surrounding noncrop habitat does not consistently improve pest management, meaning habitat conservation may bolster production in some systems and depress yields in others. Future efforts to develop tools that inform farmers when habitat conservation truly represents a win-win would benefit from increased understanding of how landscape effects are modulated by local farm management and the biology of pests and their enemies.
Article
Full-text available
Most prior studies have found that substituting biofuels for gasoline will reduce greenhouse gases because biofuels sequester carbon through the growth of the feedstock. These analyses have failed to count the carbon emissions that occur as farmers worldwide respond to higher prices and convert forest and grassland to new cropland to replace the grain (or cropland) diverted to biofuels. By using a worldwide agricultural model to estimate emissions from land-use change, we found that corn-based ethanol, instead of producing a 20% savings, nearly doubles greenhouse emissions over 30 years and increases greenhouse gases for 167 years. Biofuels from switchgrass, if grown on U.S. corn lands, increase emissions by 50%. This result raises concerns about large biofuel mandates and highlights the value of using waste products.
Article
Full-text available
Context Land-use change is a key driver of pollinator declines worldwide. Plantation forests are a major land use worldwide and are likely to expand substantially in the near term, especially with projected cellulosic biofuel production. But little is known about the potential local and landscape-scale impacts of plantation forestry on bees, the most important group of pollinators worldwide. Objectives We studied the effects of local management, landscape context, and their interaction on bee abundance and species richness in the southeastern US, in pine plantations and other nearby land uses. Methods We sampled bee communities using aerial netting and pan trapping in 85 sites over 3 years. Results We found that both landscape composition and configuration are important factors for bee diversity and abundance at the landscape scale, though interestingly many landscape factors showed contrasting directional responses for diversity versus abundance. Removing the four most common species, all in the genus Lasioglossum (and which comprised ~ 45% of all specimens) largely harmonized the results between diversity and abundance. In addition, we found several interactions between local management and landscape factors, all consistent with the idea that compositional heterogeneity and configurational complexity are more important for bee communities in poorer-quality local habitat. Conclusions Our results underscore the importance of considering (1) both landscape configuration and composition in analyses, and (2) interactions between local management and landscape factors. The interactions in particular highlight the need to maintain landscape compositional heterogeneity and configurational complexity, particularly in heavily managed landscapes.
Article
Full-text available
Although the United States has pursued rapid development of corn ethanol as a matter of national biofuel policy, relatively little is known about this policy's widespread impacts on agricultural land conversion surrounding ethanol refineries. This knowledge gap impedes policy makers' ability to identify and mitigate potentially negative environmental impacts of ethanol production. We assessed changes to the landscape during initial implementation of the Renewable Fuel Standard v2 (RFS2) from 2008 to 2012 and found nearly 4.2 million acres of arable non-cropland converted to crops within 100 miles of refinery locations, including 3.6 million acres of converted grassland. Aggregated across all ethanol refineries, the rate of grassland conversion to cropland increased linearly with proximity to a refinery location. Despite this widespread conversion of the landscape, recent cropland expansion could have made only modest contributions to mandated increases in conventional biofuel capacity required by RFS2. Collectively, these findings demonstrate a shortcoming in the existing 'aggregate compliance' method for enforcing land protections in the RFS2 and suggest an alternative monitoring mechanism would be needed to appropriately capture the scale of observed land use changes.
Article
Full-text available
Climate change and biodiversity loss are two of the greatest challenges of the 21st century. To date, actions proposed by the international community to address these problems have largely been conducted in a piecemeal fashion. Conservation biologists advocate for low-intensity management in temperate protected areas to maintain and restore biodiversity. Low-input, high-diversity biomass from such areas has been proposed as a promising alternative bioenergy feedstock. Here, we show that there is a vast unexploited biomass-for-bioenergy potential present in Natura 2000, the European nature conservation network. Spanning 7.5 million hectares (ha), non-forest ecosystems within Natura 2000 have a biomass production of 17.9 teragrams (Tg) of dry matter annually. The conversion of this biomass to bioenergy will not lead to the displacement of food production systems, thereby avoiding 12.5 Tg of carbon dioxide equivalent greenhouse-gas emissions and circumventing between 1.2 and 2.8 million ha of indirect land-use change. The use of conservation biomass as bioenergy feedstock clearly offers the opportunity to reconcile biodiversity goals and climate-change mitigation.
Article
Full-text available
Energy production in the United States for domestic use and export is predicted to rise 27% by 2040. We quantify projected energy sprawl (new land required for energy production) in the United States through 2040. Over 200,000 km² of additional land area will be directly impacted by energy development. When spacing requirements are included, over 800,000 km² of additional land area will be affected by energy development, an area greater than the size of Texas. This pace of development in the United States is more than double the historic rate of urban and residential development, which has been the greatest driver of conversion in the United States since 1970, and is higher than projections for future land use change from residential development or agriculture. New technology now places 1.3 million km² that had not previously experienced oil and gas development at risk of development for unconventional oil and gas. Renewable energy production can be sustained indefinitely on the same land base, while extractive energy must continually drill and mine new areas to sustain production. We calculated the number of years required for fossil energy production to expand to cover the same area as renewables, if both were to produce the same amount of energy each year. The land required for coal production would grow to equal or exceed that of wind, solar and geothermal energy within 2–31 years. In contrast, it would take hundreds of years for oil production to have the same energy sprawl as biofuels. Meeting energy demands while conserving nature will require increased energy conservation, in addition to distributed renewable energy and appropriate siting and mitigation.
Article
Full-text available
Growing demand for palm oil is driving its expansion into the African tropics, potentially leading to significant carbon emissions if tropical forest is converted to palm monoculture. In this first study of a Central African oil palm concession (31,800 ha), we predict that the conversion of 11,500 ha of logged forest to a palm plantation in Gabon will release 1.50 Tg C (95% CI = [1.29, 1.76]). These emissions could be completely offset over 25 years through sequestration in planned forest set-asides given a 2.6:1 ratio of logged to converted forest. Using an agricultural suitability model, we find that careful national land-use planning could largely avoid high carbon emissions while meeting goals for palm oil production. We recommend that Gabon adopts a national carbon threshold for land conversion and requires concession-level set-aside ratios that meet no-net emissions criteria as mechanisms for steering plantations away from high carbon forests.
Article
Full-text available
Current quantification of climate warming mitigation potential (CWMP) of biomass-derived energy has focused primarily on its biogeochemical effects. This study used site-level observations of carbon, water, and energy fluxes of biofuel crops to parameterize and evaluate the community land model (CLM) and estimate CO2 fluxes, surface energy balance, soil carbon dynamics of corn (Zea mays), switchgrass (Panicum virgatum), and miscanthus (Miscanthus × giganteus) ecosystems across the conterminous United States considering different agricultural management practices and land-use scenarios. We find that neglecting biophysical effects underestimates the CWMP of transitioning from croplands and marginal lands to energy crops. Biogeochemical effects alone result in changes in carbon storage of -1.9, 49.1, and 69.3 g C m⁻² y⁻¹ compared to 20.5, 78.5, and 96.2 g C m⁻² y⁻¹ when considering both biophysical and biogeochemical effects for corn, switchgrass, and miscanthus, respectively. The biophysical contribution to CWMP is dominated by changes in latent heat fluxes. Using the model to optimize growth conditions through fertilization and irrigation increases the CWMP further to 79.6, 98.3, and 118.8 g C m⁻² y⁻¹, respectively, representing the upper threshold for CWMP. Results also show that the CWMP over marginal lands is lower than that over croplands. This study highlights that neglecting the biophysical effects of altered surface energy and water balance underestimates the CWMP of transitioning to bioenergy crops at regional scales.
Article
Full-text available
Tropical forest landscapes face competing demands for conserving biodiversity, sustaining ecosystem services and accommodating production systems such as forestry and agriculture. Land-sparing and land-sharing have emerged as contrasting strategies to manage trade-offs between production and biodiversity conservation. Both strategies are evident in land-management policies at local-to-international scales. However, studies rarely report the impacts of these strategies, assessed for multiple stakeholders and multiple ecosystem services, particularly in real landscapes. Using a case study from a high-priority region for forest protection, restoration and rural development in Central Kalimantan, Indonesia, we analysed the potential outcomes under 10 alternative policy scenarios, including land-sharing, land-sparing and mixed strategies. We used a novel optimization process integrating integer programming with conservation-planning software (Marxan with Zones) to identify production possibility frontiers (PPFs), highlighting the trade-off between smallholder agriculture and oil palm, subject to achievement of a set of carbon, timber and biodiversity conservation targets. All policy scenarios modelled proved to be capable of achieving all targets simultaneously. Most strategies resulted in an expansion of the PPF from the baseline, increasing the flexibility of land allocation to achieve all targets. Mixed strategies gave the greatest flexibility to achieve targets, followed closely by land-sparing. Land-sharing only performed better than the baseline when no yield penalties were incurred, and resulted in PPF contraction otherwise. Strategies assessed required a minimum of 29-37% to be placed in conservation zones, notably protecting the majority of remaining forest, but requiring little reforestation. Policy implications. Production possibility frontiers (PPFs) can evaluate a broad spectrum of land-use policy options. When using targets sought by multiple stakeholders within an ecosystem services framework, PPFs can characterize biophysical, socio-economic and institutional dimensions of policy trade-offs in heterogeneous landscapes. All 10 policy strategies assessed in our case study are biophysically capable of achieving all stakeholder objectives, provided at least 29-37% of the landscape is conserved for biodiversity. This novel methodological approach provides practical options for systematic analysis in complex, multifunctional landscapes, and could, when integrated within a larger planning and implementation process, inform the design of land-use policies that maximize stakeholder satisfaction and minimize conflict.
Article
Full-text available
Expansion of land area used for agriculture is a leading cause of biodiversity loss and greenhouse gas emissions, particularly in the tropics. One potential way to reduce these impacts is to increase food production per unit area (yield) on existing farmland, so as to minimize farmland area and spare land for habitat conservation or restoration. There is now widespread evidence that such a strategy could benefit a large proportion of wild species, provided that spared land is conserved as natural habitat (1). However the scope for yield growth to spare land by lowering food prices and hence incentives for clearance (“passive” land sparing) can be undermined if lower prices stimulate demand, and higher profits per unit area encourage agricultural expansion, increasing the opportunity cost of conservation (2, 3). We offer a first description of four categories of “active” land-sparing mechanisms that could overcome these rebound effects by linking yield increases with habitat protection or restoration. The effectiveness, limitations and potential for unintended consequences of these mechanisms have yet to be systematically tested, but in each case we describe real-world interventions which illustrate how intentional links between yield increases and land sparing might be developed.
Article
Full-text available
In Mediterranean areas, riparian zones are particularly important for maintaining biodiversity. Nevertheless, the native vegetation in these zones has been modified or lost at an alarming rate during the last decades. The main objective of this study was to investigate the influence of poplar plantations on bird diversity in riparian zones, in order to estimate the ecological implications of a substantial expansion of poplar plantations. Breeding birds were sampled by the point-count method in twenty-four poplar plantations of I-214 clone, according to a factorial design combining stand age and understory management. Furthermore, the three native riparian forests remaining in the study area were also surveyed. Explanatory variables included (1) dendrometric, (2) understory and (3) landscape variables within six different radii of circular buffers. The species richness and abundance index were higher in riparian forests than in poplar plantations. Landscape variables (percentage of poplar plantations in the surrounding landscape) strongly influenced bird diversity in poplar plantations. Furthermore, at the local scale, understory cover was also a key factor in shaping bird assemblages. This suggests that poplar plantations should not be used as surrogates for native forests. Nevertheless, poplar plantations can still accommodate rich communities of forest bird species, providing that suitable management is applied at local and landscape levels.
Article
Full-text available
Ecologists widely use the log response ratio for summarizing the outcomes of studies for meta-analysis. However, little is known about the sampling distribution of this effect size estimator. Here I show with a Monte Carlo simulation that the log response ratio is biased when quantifying the outcome of studies with small sample sizes, and can yield erroneous variance estimates when the scale of study parameters are near zero. Given these challenges, I derive and compare two new estimators that help correct this small-sample bias, and update guidelines and diagnostics for assessing when the response ratio is appropriate for ecological meta-analysis. These new bias-corrected estimators retain much of the original utility of the response ratio and are aimed to improve the quality and reliability of inferences with effect sizes based on the log ratio of two means.
Article
Full-text available
Widespread land use changes, and ensuing effects on ecosystem services, are expected from expanding bioenergy production. Although most U. S. production of ethanol is from corn, it is envisaged that future ethanol production will also draw from cellulosic sources such as perennial grasses. In selecting optimal bioenergy crops, there is debate as to whether it is preferable from an environmental standpoint to cultivate bioenergy crops with high ecosystem services (a "land-sharing" strategy) or to grow crops with lower ecosystem services but higher yield, thereby requiring less land to meet bioenergy demand (a "land-sparing" strategy). Here, we develop a simple model to address this question. Assuming that bioenergy crops are competing with uncultivated land, our model calculates land requirements to meet a given bioenergy demand intensity based upon the yields of bioenergy crops. The model combines fractional land cover of each ecosystem type with its associated ecosystem services to determine whether land-sharing or land-sparing strategies maximize ecosystem services at the landscape level. We apply this model to a case in which climate protection through GHG regulation-an ecosystem's greenhouse gas value (GHGV)-is the ecosystem service of interest. Our results show that the relative advantages of land sparing and land sharing depend upon the type of ecosystem displaced by the bioenergy crop; as the GHGV of the unfarmed land increases, the preferable strategy shifts from land sharing to land sparing. Although it may be preferable to replace ecologically degraded land with high-GHGV, lower yielding bioenergy crops, average landscape GHGV will most often be maximized through high-yielding bioenergy crops that leave more land for uncultivated, high-GHGV ecosystems. Although our case study focuses on GHGV, the same principles will be applicable to any ecosystem service whose value does not depend upon the spatial configuration of the landscape. Whenever bioenergy crops have substantially lower ecosystem services than the ecosystems with which they are competing for land, the most effective strategy for meeting bioenergy demand while maximizing ecosystem services on a landscape level is one of land sparing: focusing simultaneously on maximizing the yield of bioenergy crops while preserving or restoring natural ecosystems.
Article
Full-text available
Maximum likelihood or restricted maximum likelihood (REML) estimates of the parameters in linear mixed-effects models can be determined using the lmer function in the lme4 package for R. As for most model-fitting functions in R, the model is described in an lmer call by a formula, in this case including both fixed- and random-effects terms. The formula and data together determine a numerical representation of the model from which the profiled deviance or the profiled REML criterion can be evaluated as a function of some of the model parameters. The appropriate criterion is optimized, using one of the constrained optimization functions in R, to provide the parameter estimates. We describe the structure of the model, the steps in evaluating the profiled deviance or REML criterion, and the structure of classes or types that represents such a model. Sufficient detail is included to allow specialization of these structures by users who wish to write functions to fit specialized linear mixed models, such as models incorporating pedigrees or smoothing splines, that are not easily expressible in the formula language used by lmer.
Article
Full-text available
Agriculture is being challenged to provide food, and increasingly fuel, for an expanding global population. Producing bioenergy crops on marginal lands-farmland suboptimal for food crops-could help meet energy goals while minimizing competition with food production. However, the ecological costs and benefits of growing bioenergy feedstocks-primarily annual grain crops-on marginal lands have been questioned. Here we show that perennial bioenergy crops provide an alternative to annual grains that increases biodiversity of multiple taxa and sustain a variety of ecosystem functions, promoting the creation of multifunctional agricultural landscapes. We found that switchgrass and prairie plantings harbored significantly greater plant, methanotrophic bacteria, arthropod, and bird diversity than maize. Although biomass production was greater in maize, all other ecosystem services, including methane consumption, pest suppression, pollination, and conservation of grassland birds, were higher in perennial grasslands. Moreover, we found that the linkage between biodiversity and ecosystem services is dependent not only on the choice of bioenergy crop but also on its location relative to other habitats, with local landscape context as important as crop choice in determining provision of some services. Our study suggests that bioenergy policy that supports coordinated land use can diversify agricultural landscapes and sustain multiple critical ecosystem services.
Article
Full-text available
Meta-analysis is a statistical technique that allows one to combine the results from multiple studies to glean inferences on the overall importance of various phenomena. This method can prove to be more informative than common ''vote counting,'' in which the number of significant results is compared to the number with nonsignificant results to determine whether the phenomenon of interest is globally important. While the use of meta- analysis is widespread in medicine and the social sciences, only recently has it been applied to ecological questions. We compared the results of parametric confidence limits and ho- mogeneity statistics commonly obtained through meta-analysis to those obtained from re- sampling methods to ascertain the robustness of standard meta-analytic techniques. We found that confidence limits based on bootstrapping methods were wider than standard confidence limits, implying that resampling estimates are more conservative. In addition, we found that significance tests based on homogeneity statistics differed occasionally from results of randomization tests, implying that inferences based solely on chi-square signif- icance tests may lead to erroneous conclusions. We conclude that resampling methods should be incorporated in meta-analysis studies, to ensure proper evaluation of main effects in ecological studies.
Article
Full-text available
We evaluated the conditions under which patch size effects are important determinants of local population density for animals living in patchy landscapes. This information was used to predict when patch size effects will be expected to occur following habitat loss and fragmentation. Using meta-analysis, we quantitatively reviewed the results of 25 published studies that tested for a relationship between patch size and population density. Patch size effects were strong for edge and interior species (negative and positive patch size effects, respectively), but negligible for generalist species that use both edge and interior habitat. We found significant differences in mean patch size effects between migratory and residential species, between herbivores and carnivores, and among taxonomic groups. We found no evidence that patch size effects were related to landscape characteristics such as the proportion of landscape covered by habitat, median patch size, or the scale at which a study was conducted. However, species in the Western Hemisphere tended to have larger absolute effect sizes, and eastern species tended to be more variable in their response. For landscapes undergoing habitat loss and fragmentation, our results predict the following: (1) among generalist species that use both the edge and the interior of a habitat patch, the decline in population size associated with habitat destruction should be accounted for by pure habitat loss alone; (2) for interior species, the decline in population size associated with habitat fragmentation per se will be greater than that predicted from pure habitat loss alone; (3) for edge species, the decline in population size will be less than that predicted by pure habitat loss alone; (4) these relative effects will not be influenced by the extent of habitat loss, but they will be affected by the pattern of habitat when large or small patches are preferentially removed; and (5) as loss and fragmentation increase within a landscape, migratory species will generally suffer less of a decline in population size than resident species.
Article
Full-text available
Little information is available on earthworm distribution and diversity in the State of Paraná, southern Brazil. Earthworm abundance and species diversity was evaluated in four land use systems near Jaguapitã, (Paraná); where pastures are being converted to soybean and sugarcane. Samples were taken during the rainy and dry seasons of 2004 and 2005 in eight sites: two old degraded pastures, an old pasture being converted to row cropping, two grain crop fields, two sugarcane fields and a native forest fragment. Twenty-five 25 × 25 cm soil blocks were taken at each site, 20 of them to 10 cm and five to 30 cm depth. Earthworms were manually sorted from the soil and preserved in formaldehyde. Earthworm species found were: the exotics Pontoscolex corethrurus (Glossoscolecidae), Dichogaster affinis, D. bolaui and D. saliens (Acanthodri-lidae), Eukerria saltensis, E. eiseniana and Ocnerodrilus occidentalis (Ocnerodrilidae), and Amynthas sp. (Megascolecidae); the native species Glossoscolex n. sp. and Fimoscolex n. sp. (Glossoscolecidae), Belladrilus n. sp.1 and an unidentifiable Ocnerodrilidae n. sp.1 (probably Belladrilus); and two unidentified Eukerria spp. (of unknown origin) (Ocnerodrilidae). Pasture conversion to row crops had a negative effect on earth-worm abundance and diversity: fewer individuals and species were found in the cropping systems than the pastures. The forest was not a suitable reference site, having low earthworm populations and diversity. Exotic species tended to predominate in the land use systems near Jaguapitã, but native earthworm species still survived, even in degraded pastures and row crops, many years after deforestation.
Article
Full-text available
In the US Corn Belt, a recent doubling in commodity prices has created incentives for landowners to convert grassland to corn and soybean cropping. Here, we use land cover data from the National Agricultural Statistics Service Cropland Data Layer to assess grassland conversion from 2006 to 2011 in the Western Corn Belt (WCB): five states including North Dakota, South Dakota, Nebraska, Minnesota, and Iowa. Our analysis identifies areas with elevated rates of grass-to-corn/soy conversion (1.0-5.4% annually). Across the WCB, we found a net decline in grass-dominated land cover totaling nearly 530,000 ha. With respect to agronomic attributes of lands undergoing grassland conversion, corn/soy production is expanding onto marginal lands characterized by high erosion risk and vulnerability to drought. Grassland conversion is also concentrated in close proximity to wetlands, posing a threat to waterfowl breeding in the Prairie Pothole Region. Longer-term land cover trends from North Dakota and Iowa indicate that recent grassland conversion represents a persistent shift in land use rather than short-term variability in crop rotation patterns. Our results show that the WCB is rapidly moving down a pathway of increased corn and soybean cultivation. As a result, the window of opportunity for realizing the benefits of a biofuel industry based on perennial bioenergy crops, rather than corn ethanol and soy biodiesel, may be closing in the WCB.
Article
Full-text available
Demand for land to grow corn for ethanol increased in the United States by 4.9 million hectares between 2005 and 2008, with wide-ranging effects on wildlife, including habitat loss. Depending on how biofuels are made, additional production could have similar impacts. We present a framework for assessing the impacts of biofuels on wildlife, and we use this framework to evaluate the impacts of existing and emerging biofuels feedstocks on grassland wildlife. Meeting the growing demand for biofuels while avoiding negative impacts on wildlife will require either biomass sources that do not require additional land (e.g., wastes, residues, cover crops, algae) or crop production practices that are compatible with wildlife. Diverse native prairie offers a potential approach to bioenergy production (including fuel, electricity, and heat) that is compatible with wildlife. Additional research is required to assess the compatibility of wildlife with different composition, inputs, and harvest management approaches, and to address concerns over prairie yields versus the yields of other biofuel crops.
Article
Full-text available
Biomass crops grown on marginal soils are expected to fuel an emerging bioenergy industry in the United States. Bioenergy crop choice and position in the landscape could have important impacts on a range of ecosystem services, including natural pest-suppression (biocontrol services) provided by predatory arthropods. In this study we use predation rates of three sentinel crop pests to develop a biocontrol index (BCI) summarizing pest-suppression potential in corn and perennial grass-based bioenergy crops in southern Wisconsin, lower Michigan, and northern Illinois. We show that BCI is higher in perennial grasslands than in corn, and increases with the amount of perennial grassland in the surrounding landscape. We develop an empirical model for predicting BCI from information on energy crop and landscape characteristics, and use the model in a qualitative assessment of changes in biocontrol services for annual croplands on prime agricultural soils under two contrasting bioenergy scenarios. Our analysis suggests that the expansion of annual energy crops onto 1.2 million ha of existing perennial grasslands on marginal soils could reduce BCI between -10 and -64% for nearly half of the annual cropland in the region. In contrast, replacement of the 1.1 million ha of existing annual crops on marginal land with perennial energy crops could increase BCI by 13 to 205% on over half of the annual cropland in the region. Through comparisons with other independent studies, we find that our biocontrol index is negatively related to insecticide use across the Midwest, suggesting that strategically positioned, perennial bioenergy crops could reduce insect damage and insecticide use on neighboring food and forage crops. We suggest that properly validated environmental indices can be used in decision support systems to facilitate integrated assessments of the environmental and economic impacts of different bioenergy policies.
Article
Full-text available
Meta-analysis provides formal statistical techniques for summarizing the results of independent experiments and is increasingly being used in ecology. The response ratio (the ratio of mean outcome in the experimental group to that in the control group) and closely related measures of proportionate change are often used as measures of effect magnitude in ecology. Using these metrics for meta-analysis requires knowledge of their statistical properties, but these have not been previously derived. The authors give the approximate sampling distribution of the log response ratio, discuss why it is a particularly useful metric for many applications in ecology, and demonstrate how to use it in meta-analysis. The meta-analysis of response-ratio data is illustrated using experimental data on the effects of increased atmospheric CO{sub 2} on plant biomass responses.
Article
Concerns over energy demands and climate change has led the United States to set ambitious targets for bioenergy production in the coming decades. The southeastern U.S. has had a recent increase in biomass woody pellet production and is projected to produce a large portion of the nation's cellulosic biofuels. We conducted a large-scale, systematic comparison of potential impacts of two types of bioenergy feedstocks–corn (Zea mays) and pine (Pinus spp.)–on bird communities across the southeastern U.S. In addition, we evaluated three biomass alternatives for woody biomass from pine plantations: thinning, residue harvest, and short-rotation energy plantations (SREPs). We conducted transect counts for birds in eight different land-uses across the region (85 sites), including corn fields, reference and plantation forests, 2013-2015. We then used hierarchical occupancy models to test the effect of these biomass alternatives on 31 species. Across all species, birds had lower rates of occupancy in corn fields compared to pine stands. Thinning had positive effects on the average occupancy across species, while residue harvest and the potential conversion of conventional plantations to SREPs had negative effects. Cavity nesters and species with bark-gleaning foraging strategies tended to show the strongest responses. These results highlight the potential negative effects of corn as an energy crop relative to the use of pine biomass. In addition, harvesting biomass via thinning was a bird-friendly harvest method in comparison to other alternatives. While SREPs may negatively impact some bird species, previously reported yields emphasize that they may provide an order of magnitude greater yield per unit area than other alternatives considered, such that this land-use practice may be an important alternative to minimize the bioenergy impacts across the landscape. This article is protected by copyright. All rights reserved.
Code
Tools for performing model selection and model averaging. Automated model selection through subsetting the maximum model, with optional constraints for model inclusion. Model parameter and prediction averaging based on model weights derived from information criteria (AICc and alike) or custom model weighting schemes. [Please do not request the full text - it is an R package. The up-to-date manual is available from CRAN].
Article
Conservation biologists are devoting an increasing amount of energy to debating whether land sparing (high-yielding agriculture on a small land footprint) or land sharing (low-yielding, wildlife-friendly agriculture on a larger land footprint) will promote better outcomes for local and global biodiversity. In turn, concerns are mounting about how to feed the world, given increasing demands for food. In this review, I evaluate the land-sparing/land-sharing framework-does the framework stimulate research and policy that can reconcile agricultural land use with biodiversity conservation, or is a revised framing needed? I review (1) the ecological evidence in favor of sparing versus sharing; (2) the evidence from land-use change studies that assesses whether a relationship exists between agricultural intensification and land sparing; and (3) how that relationship may be affected by socioeconomic and political factors. To address the trade-off between biodiversity conservation and food production, I then ask which forms of agricultural intensification can best feed the world now and in the future. On the basis of my review, I suggest that the dichotomy of the land-sparing/land-sharing framework limits the realm of future possibilities to two, largely undesirable, options for conservation. Both large, protected regions and favorable surrounding matrices are needed to promote biodiversity conservation; they work synergistically and are not mutually exclusive. A "both-and" framing of large protected areas surrounded by a wildlife-friendly matrix suggests different research priorities from the "either-or" framing of sparing versus sharing. Furthermore, wildlife-friendly farming methods such as agroecology may be best adapted to provide food for the world's hungry people. © 2015 New York Academy of Sciences.
Article
Commercial selective logging and the conversion of primary and degraded forests to agriculture are the biggest threats to tropical biodiversity. Our understanding of the impacts of these disturbances and the resulting local extinctions on the functional roles performed by the remaining species is limited. We address this issue by examining functional diversity (FD), which quantifies a range of traits that affect a species' ecological role in a community as a single continuous metric. We calculated FD for birds across a gradient of disturbance from primary forest through intensively logged forest to oil palm plantations on previously forested land in Borneo, Southeast Asia, a hotspot of imperilled biodiversity. Logged rainforest retained similar levels of FD to unlogged rainforest, even after two logging rotations, but the conversion of logged forest to oil palm resulted in dramatic reductions in FD. The few remaining species in oil palm filled a disproportionately wide range of functional roles but showed very little clustering in terms of functional traits, suggesting that any further extinctions from oil palm would reduce FD even further. Determining the extent to which the changes we recorded were due to under-utilization of resources within oil palm or a reduction in the resources present is an important next step. Nonetheless our study improves our understanding of the stability and resilience of functional diversity in these ecosystems and of the implications of land-use changes for ecosystem functioning.
Article
In the United States, government-mandated growth in the production of crops dedicated to biofuel (agrofuels) is predicted to increase the demands on existing agricultural lands, potentially threatening the persistence of populations of grassland birds they support. We review recently published literature and datasets to (1) examine the ability of alternative agrofuel crops and their management regimes to provide habitat for grassland birds, (2) determine how crop placement in agricultural landscapes and agrofuel-related land-use change will affect grassland birds, and (3) identify critical research and policy-development needs associated with agrofuel production. We find that native perennial plants proposed as feedstock for agrofuel (switchgrass, Panicum virgatum, and mixed grass–forb prairie) have considerable potential to provide new habitat to a wide range of grassland birds, including rare and threatened species. However, industrialization of agrofuel production that maximizes biomass, homogenizes vegetation structure, and results in the cultivation of small fields within largely forested landscapes is likely to reduce species richness and/or abundance of grassland-dependent birds. Realizing the potential benefits of agrofuel production for grassland birds’ conservation will require the development of new policies that encourage agricultural practices specifically targeting the needs of grassland specialists. The broad array of grower-incentive programs in existence may deliver new agrofuel policies effectively but will require coordination at a spatial scale broader than currently practiced, preferably within an adaptive-management framework.
Article
Changes in land use patterns and vegetation can trigger ecological change in occupancy and community composition. Among the potential ecological consequences of land use change is altered susceptibility to occupancy by invasive species. We investigated the responses of three introduced mammals (red deer, Cervus elaphus; wild boar, Sus scrofa; and European hare, Lepus europaeus) to replacement of native vegetation by exotic pine plantations in the Patagonian forest‐steppe ecotone using camera‐trap surveys (8633 trap‐days). We used logistic regression models to relate species presence with habitat variables at stand and landscape scales. Red deer and wild boar used pine plantations significantly more frequently than native vegetation. In contrast, occurrence of European hares did not differ between pine plantations and native vegetation, although hares were recorded more frequently in firebreaks than in plantations or native vegetation. Presence of red deer and wild boar was positively associated with cover of pine plantations at the landscape scale, and negatively associated with mid‐storey cover and diversity at the stand scale. European hares preferred sites with low arboreal and mid‐storey cover. Our results suggest that pine plantations promote increased abundances of invasive species whose original distributions are associated with woodlands (red deer and wild boar), and could act as source or pathways for invasive species to new areas.
Article
The use of biomass as feedstock for energy is often associated with increased claims on land, competition with food production and impacts on other ecosystem services. Studies on sustainability aspects of bioenergy production often indicate biodiversity as a key concern. This article presents a first comprehensive review of published impacts of bioenergy crop production on biodiversity, evaluates the drivers and pressures of biodiversity change and summarizes current trends and impacts. The review provides insight into the types of biodiversity indicators applied under a range of conditions and the mitigating measures proposed to minimize negative impacts or realize biodiversity benefits. The 53 selected publications give diverse results that are explained by the various spatial scales, production systems and regions, time horizons, methodologies and biodiversity indicators used. Reported impacts depend on initial land use and are mostly negative, especially in tropical regions. The impacts of second generation bioenergy crops tend to be less negative than first generation ones, and are in some cases positive (at the field level), in particular in temperate regions. Land-use change appears as the key driver of biodiversity change, whereas the associated habitat loss, alterations in species richness and abundance are the main impacts addressed. Such changes are often paired with the (initiation of a) process of biological homogenization. The article confirms that concerns about the expansion of bioenergy crop production not only relate to the direct effects on biodiversity by replacing natural vegetation, but increasingly to indirect effects as well. These effects have, however, shown to be difficult to quantify. At the same time, the land sparing vs. land sharing debate receives growing attention, whereas little evidence exists in bioenergy literature on the impacts of large-scale application of these strategies on (agro)biodiversity. Following the findings of the review, the article finally provides recommendations for future research.
Article
Tropical landscapes are dominated by agroecosystems, and most species that survive in forest remnants interact with these agroecosystems. The potential value of agroecosystems for aiding species survival is often ignored. Essential ecosystem services may suffer when functional groups such as pollinators and predators are affected by land use. We used agroforestry systems differing in land-use intensity to examine flower-visiting bees on coffee plants and the community structure of trap-nesting bees and wasps and their natural enemies. The number and abundance of all species of coffee-visiting bees did not show a significant correlation with land-use intensity. The abundance ( but not the number of species) of solitary bees increased with land-use intensity, whereas the abundance and number of species of social bees significantly decreased. In a further experiment, abundance and number of trap-nesting species increased with land-use intensity. These results contrast with the common expectation that intensively used agroforestry systems are characterized only by loss of species. Furthermore, they support the idea that many nonpest and beneficial insect species may even profit from agricultural land use. Parasitism and predation of trap-nest inhabitants did not change with land-use intensity, but species diversity (number of enemy species) and ecological function (mortality) were correlated.
Article
Changes in agricultural management can potentially increase the accumulation rate of soil organic C (SOC), thereby sequestering CO 2 from the atmosphere. This study was conducted to quantify potential soil C sequestration rates for different crops in response to decreasing tillage intensity or enhancing rotation complexity, and to estimate the duration of time over which sequestration may occur. Analyses of C sequestration rates were completed using a global database of 67 long-term agricultural experiments, consisting of 276 paired treatments. Results indicate, on average, that a change from conventional tillage (CT) to no-till (NT) can sequester 57 ± 14 g C m -2 yr -1 , excluding wheat (Triticum aestivum L.)-fallow systems which may not result in SOC accumulation with a change from CT to NT. Enhancing rotation complexity can sequester an average 20 ± 12 g C m -2 yr -1 , excluding a change from continuous corn (Zea mays L.) to corn-soybean (Glycine max L.) which may not result in a significant accumulation of SOC. Carbon sequestration rates, with a change from CT to NT, can be expected to peak in 5 to 10 yr with SOC reaching a new equilibrium in 15 to 20 yr. Following initiation of an enhancement in rotation complexity, SOC may reach a new equilibrium in approximately 40 to 60 yr. Carbon sequestration rates, estimated for a number of individual crops and crop rotations in this study, can be used in spatial modeling analyses to more accurately predict regional, national, and global C sequestration potentials.
Article
Growing demand for alternative energy sources has contributed to increased biofuel production, but the effects on biodiversity of land-use change to biofuel crops remain unclear. Using a meta-analysis for crops being used or considered in the US, we find that vertebrate diversity and abundance are generally lower in biofuel crop habitats relative to the non-crop habitats that these crops may replace. Diversity effects are greater for corn than for pine and poplar, and birds of conservation concern experience greater negative effects from corn than species of less concern. Yet conversion of row-crop fields to grasslands dedicated to biofuels could increase local diversity and abundance of birds. To minimize impacts of biofuel crops on biodiversity, we recommend management practices that reduce chemical inputs, increase heterogeneity within fields, and delay harvests until bird breeding has ceased. We encourage research that will move us toward a sustainable biofuels economy, including the use of native plants, development of robust environmental criteria for evaluating biofuel crops, and integrated cost-benefit analysis of potential land-use change.
Article
This study explored the relationship between landscape-level factors (land use type) and the diversity of soil mites (Acari: Oribatida, Mesostigmata) at a within-site scale, using diversity measures including point diversity (local species diversity within a single sampling point), patterns of species turnover among the sampling points, and alpha diversity (total species richness in a habitat). The land use types included corn fields, intensive short-rotation forestry plantations, two types of abandoned agricultural fields, and hardwood forests.Land use type was identified as a significant factor influencing both small-scale (within individual soil cores) and site-scale diversity of Oribatida, which increased in the order “corn→willow→abandoned fields→forests”. There was no statistical relationship between land use type and abundance or diversity of Mesostigmata.Using a bootstrapping method to generate “random” communities, we found that all land use types had significantly more diverse patterns of species abundance than was expected by chance. On the other hand, the patterns of presence/absence of species were less diverse than expected by chance. Local site factors were significant in driving the patterns of diversity of soil mites at the site scale; land use type was less important. The overall structure of Oribatida and Mesostigmata assemblages was significantly related to land use type. We conclude that soil communities respond to land management on both local scales and habitat-wide scales.
Article
All is not well for biodiversity in the tropics. Despite recent debate over the extent of future tropical extinctions and the effectiveness of reserve systems, the continued disappearance of habitat, soaring human population, and loss of vital ecosystem services demand immediate action. This crisis is worrying, given that tropical regions support over two-thirds of all known species and are populated by some of the world's poorest people, who have little recourse to lower environmental-impact lifestyles. Recent evidence has shown that - in addition to unabated rates of forest loss - coastal development, overexploitation of wildlife, catchment modification, and habitat conversion are threatening human well-being. We argue that the recent technical debate about likely extinctions masks the real issue - that, to prevent further loss of irreplaceable tropical biodiversity, we must err on the side of caution. We need to avoid inadvertently supporting political agendas that assume low future extinction rates, because this will result in further destruction of tropical biodiversity.
Article
Tropical ecosystems are globally important for bird diversity. In many tropical regions, land-use intensification has caused conversion of natural forests into human-modified habitats, such as secondary forests and heterogeneous agricultural landscapes. Despite previous research, the distribution of bird communities in these forest-farmland mosaics is not well understood. To achieve a comprehensive understanding of bird diversity and community turnover in a human-modified Kenyan landscape, we recorded bird communities at 20 sites covering the complete habitat gradient from forest (near natural forest, secondary forest) to farmland (subsistence farmland, sugar-cane plantation) using point counts and distance sampling. Bird density and species richness were on average higher in farmland than in forest habitats. Within forest and farmland, bird density and species richness increased with vegetation structural diversity, i.e., were higher in near natural than in secondary forest and in subsistence farmland than in sugarcane plantations. Bird communities in forest and farmland habitats were very distinct and very few forest specialists occurred in farmland habitats. Moreover, insectivorous bird spe-cies declined in farmland habitats whereas carnivores and herbivores increased. Our study confirms that tropical farmlands can hardly accommodate forest specialist species. Contrary to most previous studies, our findings show that structurally rich tropical farmlands hold a surprisingly rich and distinct bird community that is threatened by conversion of subsistence farmland into sugarcane plantations. We conclude that conservation strategies in the tropics must go beyond rain forest protection and should integrate structurally heteroge-neous agroecosystems into conservation plans that aim at maintaining the diverse bird communities of tropical forest-farmland mosaics.
Article
Short-rotation woody cropping (SRWC) refers to silvicultural systems designed to produce woody biomass using short harvest cycles (1–15 years), intensive silvicultural techniques, high-yielding varieties, and often coppice regeneration. Recent emphasis on alternatives to fossil fuels has spurred interest in producing SRWC on privately owned and intensively managed forests of North America. We examined potential bird and small mammal response at the stand level to conversion of existing, intensively managed forests to SRWCs using meta-analysis of existing studies. We found 257 effect sizes for birds (243 effect sizes) and mammals (14 effect sizes) from 8 studies involving Populus spp. plantations. Diversity and abundance of bird guilds were lower on short-rotation plantations compared with reference woodlands, while abundance of individual bird species was more variable and not consistently higher or lower on SRWC plantations. Shrub-associated birds were more abundant on SRWC plantations, but forest-associated and cavity-nesting birds were less abundant. Effects on birds appeared to decrease with age of the SRWC plantation, but plantation age was also confounded with variation in the type of reference forest used for comparison. Both guilds and species of mammals were less abundant on SRWC plantations. These conclusions are tentative because none of these studies directly compared SRWC plantations to intensively managed forests. Plantations of SRWCs could contribute to overall landscape diversity in forest-dominated landscapes by providing shrubby habitat structure for nonforest species. However, extensive conversion of mature or intensively managed forests to SRWC would likely decrease overall diversity, especially if they replace habitat types of high conservation value.
Article
Aim Worldwide, functional homogenization is now considered to be one of the most prominent forms of biotic impoverishment induced by current global changes. Yet this process has hardly been quantified on a large scale through simple indices, and the connection between landscape disturbance and functional homogenization has hardly been established. Here we test whether changes in land use and landscape fragmentation are associated with functional homogenization of bird communities at a national scale. Location France. Methods We estimated functional homogenization of a community as the average specialization of the species present in that community. We studied the spatial variation of this community specialization index (CSI) using 1028 replicates from the French Breeding Bird Survey along spatial gradients of landscape fragmentation and recent landscape disturbance, measured independently, and accounting for spatial autocorrelation. Results The CSI was very sensitive to both measures of environmental degradation: on average, 23% of the difference in the CSI values between two sample sites was attributed to the difference in fragmentation and the disturbance between sites. This negative correlation between CSI and sources of landscape degradation was consistent over various habitats and biogeographical zones. Main conclusions We demonstrate that the functional homogenization of bird communities is strongly positively correlated to landscape disturbance and fragmenta-tion. We suggest that the CSI is particularly effective for measuring functional homogenization on both local and global scales for any sort of organism and with abundance or presence–absence data.
Article
We examined the potential local- and landscape-level impacts of different biofuel production systems on biocontrol, an important service provided by arthropod natural enemies. Specifically, we sampled natural enemies with sweep nets and measured predation of sentinel pest eggs in stands of corn, switchgrass and mixed prairie in Michigan and Wisconsin (total n=40 for natural enemy sampling, n=60 for egg predation), relating them to crop type, forb cover and diversity, and the composition and heterogeneity of the surrounding landscape. Grasslands with intermediate levels of forb cover and flower diversity supported two-orders of magnitude more natural enemy biomass, fourfold more natural enemy families, and threefold greater rates of egg predation than corn. Data suggest this was in part due to a general increase in biomass, richness and predation in perennial grasslands compared with corn, combined with a positive effect of intermediate levels of forb cover and flower diversity. Specifically, natural enemy biomass and family richness showed hump-shaped relationships to forb cover that peaked in sites with 5–25% forbs, while egg predation increased with floral diversity. At the landscape scale, both natural-enemy biomass and egg predation increased with the area of forest in the landscape, and egg predation almost doubled as the area of herbaceous, perennial habitats within 1.5 km of study sites increased. Our results suggest that floristically diverse, perennial grasslands support diverse and abundant predator communities that contribute to natural pest suppression. In addition, large-scale production of biofuel crops could positively or negatively affect biocontrol services in agricultural landscapes through associated changes in the area of perennial habitats. Biofuel landscapes that incorporate perennial grasslands could support a variety of beneficial organisms and ecosystem services in addition to producing biomass.
Article
Expansion of agriculture is a principal driver of biodiversity losses in the tropics, prompting suggestions that plantations should be made more hospitable to wildlife. Such “wildlife-friendly” practices contrast with the alternative “land sparing” strategy, which promotes separation of agricultural and conservation areas. Focusing on the wildlife-friendly strategy of retaining fragments of forest within the agricultural matrix, here we report the abundance and diversity of birds within oil palm plantations, fragments, and contiguous forest. Abundances of imperiled bird species were 60 times lower in fragments and 200 times lower in oil palm than in contiguous forest. Forest fragments also did not increase bird abundances in adjacent oil palm, had lower species richness than contiguous forest, and had an avifaunal composition that was more similar to oil palm than to contiguous forest. Therefore, from a conservation perspective, any investment in the retention of fragments would be better directed toward the protection of contiguous forest.
Article
Oil palm is one of the world's most rapidly expanding equatorial crops. The two largest oil palm-producing countries—Indonesia and Malaysia—are located in Southeast Asia, a region with numerous endemic, forest-dwelling species. Oil palm producers have asserted that forests are not being cleared to grow oil palm. Our analysis of land-cover data compiled by the United Nations Food and Agriculture Organization suggests that during the period 1990–2005, 55%–59% of oil palm expansion in Malaysia, and at least 56% of that in Indonesia occurred at the expense of forests. Using data on bird and butterfly diversity in Malaysia's forests and croplands, we argue that conversion of either primary or secondary (logged) forests to oil palm may result in significant biodiversity losses, whereas conversion of pre-existing cropland (rubber) to oil palm results in fewer losses. To safeguard the biodiversity in oil palm-producing countries, more fine-scale and spatially explicit data on land-use change need to be collected and analyzed to determine the extent and nature of any further conversion of forests to oil palm; secondary forests should be protected against conversion to oil palm; and any future expansion of oil palm agriculture should be restricted to pre-existing cropland or degraded habitats.
Article
Recently, an active debate has emerged around greenhouse gas emissions due to indirect land use change (iLUC) of expanding agricultural areas dedicated to biofuel production. In this paper we provide a detailed analysis of the iLUC effect, and further address the issues of deforestation, irrigation water use, and crop price increases due to expanding biofuel acreage. We use GLOBIOM – an economic partial equilibrium model of the global forest, agriculture, and biomass sectors with a bottom-up representation of agricultural and forestry management practices. The results indicate that second generation biofuel production fed by wood from sustainably managed existing forests would lead to a negative iLUC factor, meaning that overall emissions are 27% lower compared to the “No biofuel” scenario by 2030. The iLUC factor of first generation biofuels global expansion is generally positive, requiring some 25 years to be paid back by the GHG savings from the substitution of biofuels for conventional fuels. Second generation biofuels perform better also with respect to the other investigated criteria; on the condition that they are not sourced from dedicated plantations directly competing for agricultural land. If so, then efficient first generation systems are preferable. Since no clear technology champion for all situations exists, we would recommend targeting policy instruments directly at the positive and negative effects of biofuel production rather than at the production itself.