毕业论文英文 Impacts Of Biofuel Expansion In Biodiversity Hotspots
The finitude of fossil fuels, concerns for energy security and the need to respond to climate change have led to growing worldwide interests in biofuels. However, a significant proportion of conventional biofuel feedstocks is produced in biodiversity hotspots in the tropics, notably oil palm in Southeast Asia, and soy and sugarcane in Brazil. This is a worrying trend for many tropical biologists because it is also within the tropics where majority of the world�s biodiversity hotspots are located (Myers et al. 2000). For at least the next decade, first generation biofuels will still be in demand. In biodiversity hotspots, where a myriad of anthropogenic factors are already driving intense land use conflicts, biofuels production will pose an additional challenge to the preservation of the remaining natural habitats. Here we address the following questions: How does biofuel expansion threaten biodiversity hotspots? How can we reconcile biofuel expansion with biodiversity conservation in these hotspots?
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X.1. Biofuels in biodiversity hotspots
Approximately 80% of total world energy supply is derived from fossil fuels such as oil, natural gas and coal. Fossil fuels are finite sources of energy and are estimated to last anywhere from 41 to ~700 years, depending on production and consumption rates (Goldemberg and Johansson 2004; Goldemberg 2007). Growing demand for energy from industrialized nations, such as the U.S., as well as emerging economies, such as China and India, will continue to place tremendous pressures on world petroleum supplies in the next few decades (Worldwatch Institute 2007). This trend is reflected in the price of crude oil, which has risen from ~US$25 per barrel in January 2000 to ~US$76 per barrel in January 2010 (peaking at ~US$140 per barrel in June 2008) (EIA-DOE 2010). As such, many countries are seeking to diversify their energy portfolio. Growing concerns over anthropogenic climate change have also driven countries to search for alternatives to fossil fuels that can help lower greenhouse gas emissions and slow the pace of global warming.
These pressing global energy and environmental challenges have at least partly driven the recent worldwide interest in biofuels. Both developed (e.g. the U.S.) and developing nations (e.g. China) view biofuels as a renewable energy source that can help achieve energy security, decrease greenhouse gas emissions and fulfill rural development standards (Fulton et al. 2004, Armbruster and Coyle 2006, Pickett et al. 2008). Between 1980 and 2005, global biofuel production increased from 4.4 to 50.1 billion litres (Murray 2005, Armbruster and Coyle 2006). Recently, several of these countries have also announced ambitious targets for switching from fossil fuels to renewable fuels (Worldwatch Institute 2007).
Biofuels are renewable fuels derived from biological feedstocks. Currently, the most widely used liquid biofuels in the transportation sector are bioethanol and biodiesel. Bioethanol is produced from the fermentation of corn (Zea mays), sugar-cane (Saccharum spp.), or other starch- or sugar-rich crops. Biodiesel is manufactured from vegetable oil (e.g. soybean (Glycine max L.), oil palm (Elaeis guineensis) or animal fats. At present, bioethanol is primarily produced from corn in the U.S., and from sugarcane in Brazil. Biodiesel is produced largely from rapeseed and sunflower seed oil in Europe, and soybean oil in the U.S. However, there is a steadily growing demand for palm oil produced in the tropics due to its much higher yield (~5,000 litres per ha compared to ~1,200 litres per ha for rapeseed), and hence lower production costs (Worldwatch Institute 2007). This is a worrying trend for many tropical biologists because it is also within the tropics where majority of the world�s biodiversity hotspots are located (Conservation International 2010; www.biodiversityhotspots.org). Furthermore, high proportions of yet forested lands in these hotspots may be suitable for biofuel production (Table 1). A recent study estimated that an increase in global biodiesel production capacity to meet future biodiesel demands (an estimated 277 million tons per year by 2050) may lead to potential habitat losses of between 0.4 million to 114.2 million ha within these hotspots, depending on the feedstock (Koh 2007). Without proper mitigation guidelines, the future expansion of biodiesel feedstock production in biodiversity hotspots will likely threaten their native biodiversity (Mittermeier et al. 2004).
Some researchers argue that �next generation� biofuels, produced from non-food feedstocks such as agricultural wastes, can fulfill many of the promises of renewable fuels without much of the environmental ills. These second and third generation biofuels are currently too costly to be produced on a commercial scale. Nevertheless, they may become more readily available and affordable in the future through technological breakthroughs, driven by strong governmental support and a string of local government and international subsidies and initiatives (Doornbosch and Steenblik 2007). Even so, next generation biofuels may not be completely free of environmental tradeoffs. A recent study that analyzed the potential environmental impacts of a global, aggressive cellulosic biofuels programme, projected major losses for biodiversity within biodiversity hotspots both directly, by replacing native habitats, or indirectly, by displacing other agricultural land uses onto native habitats (Melillo et al. 2009).
For at least the next decade, first generation biofuels will still be in demand (OECD-FAO 2008). In biodiversity hotspots, where a myriad of anthropogenic factors are already driving intense land use conflicts, adding biofuels as another demand on the land will make the preservation of the remaining natural habitats an even greater challenge. Hence, it is imperative for us to assess the impacts of biofuel expansion on biodiversity hotspots by asking the following two questions: (1) How does biofuel expansion threaten biodiversity within biodiversity hotspots? (2) How might we reconcile biofuel expansion with biodiversity conservation in these hotspots?
X.2. How does biofuel expansion threaten biodiversity within biodiversity hotspots?
X.2.1. Habitat loss
毕业论文英文 Impacts Of Biofuel Expansion In Biodiversity Hotspots
Currently, biodiversity hotspots in Southeast Asia and Latin America are under the greatest threat of biofuel expansion, namely from oil palm, sugarcane and soybean expansion. Based on land-cover data compiled by the Food and Agricultural Organisation of the United Nations, Koh and Wilcove (2008) calculated an expansion of 1.8 million ha of oil palm in Malaysia and 3 million ha in Indonesia between 1995 and 2005. Approximately 55-59% of this oil palm expansion in Malaysia and at least 56% of that in Indonesia occurred at the expense of primary or logged over forests. In Brazil, the area of soybean expansion increased dramatically by 10 million ha, from 11.6 million to 22.9 million ha between 1995 and 2005 (FAO 2010). Successful expansion of soybean has been driven by a biotechnological breakthrough�the development of soybean-bacteria combinations with pseudosymbiotic relationships, which allows soybeans to be planted with little or no application of nitrogen fertilizers (Fearnside 2001)). Although much of this soybean expansion has occurred on non-forested lands, particularly in the Cerrado, this natural grassland ecosystem nonetheless contains high concentrations of endemic and threatened species and has been delineated as a biodiversity hotspot (Fearnside 2001). Sugarcane expansion in Brazil has almost doubled from 4.5 million ha in 1995 to 8.1 million ha in 2008, with a rapid increase of 2.3 million ha between 2005 and 2008 (FAO 2010). Even though sugarcane plantings so far have mostly replaced pasture lands, continued expansion of sugarcane-bioethanol into the Center West of Brazil will likely displace cattle ranchers and soybean producers onto the Amazon and Atlantic Forest and lead to extensive deforestation (Martinelli and Filoso 2008; Lapola et al. 2010). The expansion of biofuel industries is not the only cause of habitat loss in these areas; other causes include large-scale commercial logging, pulp and paper industries, cattle ranching, shifting cultivation, mining, urban development and agricultural expansion of other crops (Angelsen and Kaimowitz 1999). However, growing global demand for palm oil, soybean and sugarcane for biofuels will likely exacerbate deforestation in these hotspots over the next decade (IATP 2008).
X.2.2. Biodiversity loss
Conversion of natural habitats into monocultures, by definition, implies a drastic loss in biodiversity and change in the composition of species communities in the area. Oil palm plantations contain less than half as many vertebrate species as primary forests (Fitzherbert et al. 2008). Forest bird species declined by 73%-77% (Koh and Wilcove 2008) and only 10% of mammal species were detected in oil palm plantations (Maddox et al. 2007). Endangered species such as the Sumatran tiger (Panthera tigris sumatrae), tapirs (Tapirus indicus) and clouded leopards (Neofelis nebulosa) were never recorded in oil palm plantations; and most mammals even preferred marginal and heavily degraded landscapes, such as shrublands, to oil palm (Maddox et al. 2007). Mammals that do occur in oil palm plantations tend to be of low conservation value, and are dominated by a few generalist species such as the wild pig (Sus scrofa), bearded pig (Sus barbatus), leopard cat (Prionailurus bengalensis) and common palm civet (Paradoxurus hermaphroditus) (Maddox et al. 2007). On the other hand invertebrate taxa showed greater variation between oil palm plantations and natural forests (Fitzerherbert et al. 2008). For example, the conversion of forests to oil palm caused forest butterfly species to decline by 79%-83% (Koh and Wilcove 2008); whereas ants, moths and bees showed a higher total species richness in oil palm than forests (Danielsen et al. 2009). Nevertheless, studies consistently showed a dominance of non-forest invertebrate species in oil palm plantations (Danielsen et al. 2009). Comparing across both vertebrate and invertebrate taxa, a mean of only 15% of species recorded in primary forest could be found in oil palm plantations (Fitzherbert et al. 2008). Not surprisingly, plant diversity within oil palm plantations was impoverished compared to forests due to regular maintenance and replanting (every 25 to 30 years) of oil palm fields (Fitzherbert et al. 2008; Danielsen et al. 2009). Biodiversity loss from soybean and sugarcane production has not been as well studied as oil palm but is expected to be significant by virtue of large scale natural habitat conversion (Fearnside 2001). The Cerrado is the largest savanna region in South America and contains a rich diversity of different vegetation types, from tree and scrub savanna, grasslands with scattered trees and patches of dry, closed canopy forests known as the Cerrad�o (Conservation International 2010). This region contains a large number of plant (10,000 species) and animal species (2,000 species), including many endemic species such as the maned wolf (Chrysocyon brachyurus), the giant armadillo (Priodontes maximus) and the giant anteater (Myrmecophaga tridactyla) (Conservation International 2010). The ecotone between forest and cerrado is also rich in endemic plant species (Fearnside and Ferraz 1995). Unfortunately, this ecosystem has also been widely cleared for soybean expansion as it is the least protected ecosystem in Brazil, with only 1.5% protected within federal reserves (Casson 2003).
X.2.3. Environmental pollution
Apart from habitat loss, biofuel industries can threaten biodiversity hotspots by causing environmental pollution and degradation through poor farming practices. Inappropriate management practices such as intensive usage of fertilizers and pesticides as well as using fires for land clearing could lead to environmental problems such as soil degradation, and water and air pollution, which in turn could lead to long-term ecological impacts on these biodiversity hotspots. For soybean and sugarcane, which are both annual crops, the ecosystem of the agricultural landscape is disrupted yearly and requires high inputs of fertilizers, pesticides and weed control to maintain high levels of production (Casson 2003; Martinelli and Filoso 2008). For sugarcane production, bare soils are exposed to intense winds and rains during management practices which can result in soil erosion rates of up to 30 tons/ha/year (Sparovek and Schnug 2001; Martinelli and Filoso 2008). Soil erosion as a result of soybean cultivation amounts to similar rates of losses between 19 and 30 tons/ha/year depending on soybean management practices, land aspect and soil type (Tomei and Upham 2009). Mature oil palm plantations in Malaysia have a soil erosion rate of approximately 7.7 to 14 tons/ha/year (Hartemink 2006). Soil erosion in oil palm plantations can be even more serious in the early years when a complete palm canopy has not yet been established, which is why maintaining a legume crop cover is important to protect against soil erosion (Corley and Tinker 2003).
Surface runoff as a result of soil erosion brings organic matter and agro-chemicals into aquatic systems which can lead to deterioration of aquatic habitats and affect the biodiversity downstream. For example, contaminants such as atrazine, a herbicide used in sugarcane crops, and heavy metals like copper, were found in water samples and stream bed sediments collected from waterways flowing through areas of extensive sugarcane cultivation (Carvalho et al. 1999, Azevedo et al. 2004, Corbi et al. 2006). High levels of nitrogen fertilizer used for sugarcane crops can lead to the excessive accumulation of nitrogen into aquatic systems. Filoso et al. (2003) reported high rates of nitrogen export into rivers draining watersheds such as the Piracicaba and Mogi river basins which are heavily cultivated with sugarcane. As a legume, soybean cultivation requires little nitrogen inputs but do require agrochemicals to combat diseases, weeds and pests. The concentration of these agrochemicals in water bodies surrounded by soybean plantations may also accumulate in fishes caught for human consumption (Fearnside 2001). Waste products and by-products of the industrial processing of sugarcane and palm oil into ethanol and crude palm oil respectively are highly pollutive and are a large source of pollution if released into the environment without proper treatment. Palm oil mill effluent (POME) and vinasse from sugarcane distillation are rich in organic matter and contribute to eutrophication and depletion of dissolved oxygen levels in aquatic systems if left untreated (Donald 2004; Martinelli and Filoso 2008). Despite the existence of present technologies to treat mill effluents, it is not uncommon for leakages and discharge from small mills to happen, leading to adverse impacts on aquatic ecosystems (Martinelli and Filoso 2008; Sheil et al. 2009)).
Burning is a common crop management practice in Brazil for facilitating the harvesting of sugarcane and has been used to clear natural vegetation for oil palm and soybean expansion in Indonesia and Brazil (Casson 2003; Martinelli and Filoso 2008; Sheil et al. 2009). The burning of the straw and leaves of sugarcane greatly facilitates the process of harvesting and drives out snakes which may pose a danger to the cane cutters (Martinelli and Filoso 2008). However, it also contributes to a higher concentration of suspended aerosols in the atmosphere (Lara et al. 2005) and leads to increases in soil temperature, decreases in soil water content and soil degradation (Dourado-Net et al. 1999; Oliveira et al. 2000; Tominaga et al. 2002). Oil palm expansion has been partially responsible for the devastating 1997-1998 forest fires in Indonesia, where satellite imagery showed fires were started by oil palm companies to clear land (Dennis et al. 2005). The dry conditions brought about by the El Nino phenomenon exacerbated the fires which burnt 11.6 million ha of land, more than half of which were montane, lowland and peat forests (Tacconi 2003). Fires are used to clear forests because they are a quick and cheap way to clear land (Guyon and Simorangkir 2002) and they lead to forest degradation which allows oil palm companies to acquire land use permits more easily(Casson 2000). In Brazil, the El Nino effect also led to serious droughts in the North and North-East and fires ignited in the savanna areas for pasture and agricultural crops like soybean blazed out of control, contributing to serious forest fires in the North (Casson 2003).
X.2.4. Interaction with other frontier opening activities
The development of biofuel plantations is associated with other drivers of habitat loss and degradation such as industrial activities like logging or cattle ranching and the building of infrastructure such as roads and waterways. This increases the accessibility of natural resources for further exploitation and heightens the level of fragmentation and isolation of remnant natural habitats. Oil palm plantations have been associated with logging companies as the profits obtained from the sale of timber can help cover part of the establishment costs of an oil palm plantation (Casson 2000). In cases where companies seek short-term profits or are unwilling to take the risks in developing oil palm industries in infrastructure-poor regions (e.g. Papua and Kalimantan), application for licenses to establish oil palm estates provide a loophole for these companies to clear-cut forests without the use of sustainable management practices for the timber extracted (Casson 2000). This explains why less than 1 million ha out of 5.3 million ha of land allocated to oil palm development have actually been planted with oil palm in Kalimantan (Casson et al. 2007). The expansion of soybean in Brazil has been linked to both charcoal production and cattle ranching (Casson 2003). Soybean expansion provides access to Cerrado trees which are used by the Brazilian steel industry for charcoal production. Profits generated by selling the Cerrado trees to charcoal producers have helped soybean farmers to further soybean expansion. The degradation of gallery forests due to the extraction of such trees has raised concern as these forests provide a corridor that links the Amazon and the coastal forests with the Cerrado and is an important habitat for several endemic fauna (Tengn�s and Nilsson 2003). The advance of large-scale mechanized soybean farms as a result of government policies and soybean technologies pushed small-scale farmers into the Amazonian frontier where agricultural expansion and pasture development took place at the expense of forests (Skole et al. 1994; Schneider et al. 2000). Fearnside (2001) describes how soybean expansion has led to major infrastructure developments in Brazil and highlights the potential for habitat exploitation due to greater accessibility in the region.
The threats to biodiversity hotspots from biofuel expansion are both direct (habitat replacement and environmental pollution) and indirect (displacement of other activities into natural habitats and increasing accessibility for further exploitation). However, these impacts are not only limited to biofuel production and have surfaced in other agricultural expansion for industry (e.g. rubber [(Li et al. 2007)] and timber (Fredericksen and Putz 2003)]) as well as food production (e.g. rice, coffee, cocoa [see Donald 2004]). The underlying reason for these damaging impacts are poor agricultural practices and policies which focus on the maximization of profits and productivity without taking into consideration the sustainability of the agricultural system and the costs to the environment (IATP 2008). Reducing the biodiversity impacts of biofuel expansion would require a change in production systems and policies and a set of stringent criteria to ensure that biofuels are produced at little cost to biodiversity and ecological systems. Considering the initial environmental reasons for using biofuels over fossil fuels, it would be a cruel irony if they are to be produced at the expense of biodiverse regions and result in more harm than good to the environment.
X.3. How can we reconcile biofuel expansion with biodiversity conservation in these hotspots?
Reconciling biofuel expansion with biodiversity conservation is not a straightforward process due to the links between the biofuel industry and both the agricultural and energy sector. A careful assessment of land use allocation options and major restructuring of the agricultural management system may be required for biofuel expansion to proceed with little or no environmental costs. Additionally, the development of energy-efficient transportation systems and advancement of second and third generation biofuels will help alleviate demand for conventional biofuel feedstocks. However, these actions will require a considerable amount of time, resources and long-term commitment from society. From a biodiversity perspective, there is an added urgency to also work on immediate solutions to minimize the loss of threatened biodiversity to biofuel expansion within these hotspots.
毕业论文英文 Impacts Of Biofuel Expansion In Biodiversity Hotspots
X.3.1. Degraded lands
Clearly, the obvious solution is to avoid planting biofuel feedstocks on native natural habitats (IATP 2008). The replacement of biodiverse habitats with monoculture plantations is without a doubt the greatest threat to biodiversity in these hotspots. Moreover, as many of these hotspots contain high levels of endemic flora and fauna, the loss of these habitats would result in global extinctions of numerous species (Myers et al. 2000). The removal of critical ecosystems for biofuel production negates any benefits accrued from the use of biofuels over fossil fuels (Gibbs et al. 2008). Some researchers have argued for the use of �degraded lands� for biofuel cultivation. However, this proposal is not as straightforward as it seems. Should the definition of �degraded� be stretched to include secondary logged forests, then biodiversity losses will continue as such forests still preserve a significant portion of primary forest biodiversity (Dunn 2004; Barlow et al. 2007; Koh & Wilcove 2008). In some cases, degraded lands have been shown to be utilized by high conservation value species like the Sumatran tiger and the value of their biodiversity cannot be judged simply based on the vegetation structure and characteristic of the landscape (Maddox 2007). Significant amounts of fertilizers and weed control are also required to convert alang-alang grasslands into oil palm plantations (Fairhurst and McLaughlin 2009) and insecure land tenure regarding degraded lands pose big risks to any biofuel feedstock producing company investing in plantation development (Cotula et al. 2008). Degraded lands can also be open to other land uses such as restoration ecology, cattle ranching, settlements and urbanization, hence strategies to expand biofuel production into degraded lands must be approached with caution.
X.3.2. PES and REDD
Apart from their biodiversity values, it is imperative to recognize the ecosystem services natural habitats provide including genetic diversity, carbon sequestration, water cycling and purification, climate regulation and many other non-timber products which are not found elsewhere (Constanza et al. 1997). The establishment and enforcement of protected areas in biodiversity hotspots remains a top strategic priority for protecting biodiversity, but these legislative tools could be supplemented with innovative schemes, such as Payment for Ecosystem Services (PES) or Reducing Emissions from Deforestation and Degradation (REDD), which create financial incentives to divert agricultural expansion away from forests and onto pre-existing croplands or degraded lands. The question which follows then is whether such incentives are sufficient to counter strong market forces that favour natural habitat conversion. Recent REDD scheme partnerships between non-governmental organizations and private companies (Fisher 2009) are positive steps towards greater collaboration and engagement of various stakeholders towards conserving forests in biodiversity hotspots. However, few studies have compared the feasibility of such schemes against current market prices for biofuel feedstocks. Butler et al. (2009) compared the profitability of converting forests into oil palm plantations against conserving forests for an REDD scheme. Under current voluntary carbon markets, conversion of forest into oil palm (yielding net present values of US$3835-$9630) will be more profitable to landowners than preserving it for carbon credits (US$614-$994). However, should REDD become a legitimate emissions reduction activity under the second commitment period of the Kyoto Protocol (2013-17), carbon credits traded in Kyoto-compliance markets have a fighting chance to compete with oil palm agriculture or other similarly profitable human activity as an economically attractive land-use option. Similar economic evaluations of comparing the value of non-forest biodiverse habitats like the Cerrado to soybean and sugarcane production in Brazil can also be carried out to determine the competition of various land uses based on monetary values. A recent study by Igari et al. (2009) calculated an annual profitability of US$134/ha/year and US$149/ha/year for sugarcane and soybean crop respectively growing near the Cerrado region in Sao Paulo State, Brazil. Opportunity costs to set aside the Cerrado for preservation were much higher compared to PES values of US$27 and US$42 per ha paid to landowners in Mexico and Costa Rica respectively (Munoz-Pina et al. 2008; Barton et al. 2009) and only slightly comparable, US$111 per ha, with the average annual value paid by USDA Conservation Reserve Programme in the United States (USDA 2006; Baylis et al. 2008). Considerable amount of research is currently underway to use REDD as a tool against natural habitat conversion by other land uses (Mongabay 2010). However, for natural habitats which are already slated for land use conversion, complete avoidance is not a realistic option and strategies to mitigate biodiversity impacts will have to be formulated.
X.3.3. Improve management practices
To partially reconcile biofuel expansion with biodiversity conservation, a set of compromises regarding biodiversity loss and a great deal of collaboration with biofuel producers will be required. It will be imperative for conservation groups to engage with biofuel producers of various levels � from small farmers to large private companies, to help producers and growers recognize the value and importance of biodiversity in the unique habitats where they grow their biofuel crops. As soybean and sugarcane are annual crops, little can be done to preserve biodiversity within the agricultural landscape when great disturbances to the landscape occur during harvest seasons. Fewer disturbances occur in oil palm plantations which are perennial crops that last for a period of 25 to 30 years. In these artificial habitats, (Koh 2008a) demonstrated that various local vegetation characteristics such as percentage ground cover of weeds, epiphyte prevalence and presence of leguminous crops can help enhance native bird and butterfly species richness. On a landscape level, the percentage of natural forest cover was able to explain 1.2-12.9% of variation in butterfly species richness and 0.6-53.3% of variation in bird species richness. Adoption of such measures is not just important to make oil palm plantations more hospitable for native biodiversity. Bird-exclusion experiments in oil palm plantations have shown a significant increase in herbivory damage by herbivorous insects, providing an economic justification for conserving remnant natural habitats for this natural pest control service (Koh 2008b). Many oil palm plantations have also included integrated pest management systems which favour the use of non-chemical pest control methods such as the establishment of �beneficial plants� (e.g. Euphorbia heterophylla) to attract insect predators and parasitoids of oil palm pests (e.g. the wasp Dolichogenidea metesae [Basri et al. 1995; Corley & Tinker 2003]). Other means of mitigating the impacts on biodiversity loss within the oil palm plantation landscape include the formation of riparian buffer zones to reduce water pollution, preservation of high conservation value (HCV) forests, formation of wildlife buffer zones to �soften� the edge between plantations and natural forests and the creation of habitat corridors to link remnant forest patches together (Maddox 2007; Fitzherbert et al. 2008). Even with the employment of all these responsible management practices, oil palm and other biofuel plantations will still have a considerable residual impact on the environment. In such cases, biodiversity offsets which is the calculation of the residual impact and paying off by conserving another natural habitat, have been proposed to ensure full compensation to the environmental damage incurred by the plantation (Maddox 2007).
毕业论文英文 Impacts Of Biofuel Expansion In Biodiversity Hotspots
X.3.4. Certification schemes
To ensure that biofuel and biofuel feedstock producers are encouraged to adopt environmentally friendly practices, international certification schemes which satisfy a set of social and environmental criteria have been introduced. Creation of multi-stakeholder organizations such as the Roundtable of Sustainable Biofuels (RSB), the Roundtable of Responsible Soy (RTRS), the Better Sugarcane Initiative (BSI) and the Roundtable of Sustainable Palm Oil (RSPO) aim to engage a diverse range of biofuel-sector stakeholders � governments, non-governmental organizations, producers, consumers, suppliers � to work towards producing biofuel feedstocks using sustainable practices. These organizations create, verify and certify performance standards for sustainable production of biofuel feedstocks and biofuels (UNEP 2009). Within these organizations, conservation groups have a platform to engage and inform producers of suitable new areas for biofuel expansion which will lead to the least ecological damage. Independent Environmental Impact Assessments (EIAs) of future biofuel crop plantings and Life-Cycle Analyses (LCAs) of biofuel products provide greater transparency on the costs of production of biofuels and reassure consumers that biofuels purchased are produced with the best sustainable practices (UNEP 2009). However, critics of biofuel certification schemes argue that market-based product certification often cover only a fraction of the market size (Sto et al. 2005; Liu et al. 2004) and may be misleading as some production appear to be sustainable but in actual fact are not (Doornsbach & Steenblik 2007). Most importantly, it has no control over the extent of indirect land use change resulting from displacement of other land use activities by biofuel production (Doornsbach & Steenblik 2007).
X.3.5. Designer landscapes
Addressing the problems arising from indirect land use changes require a landscape-level approach where biofuel feedstock production has to be coordinated within the industry and with regional or national land-use plans (Maddox 2007; Koh et al. 2009). From an ecological perspective, two concepts have been proposed to minimize the adverse impacts of agricultural expansion on biodiversity � land sparing and wildlife-friendly farming. The former seeks to minimize land area required for farming by land intensification through maximizing yields and the latter tries to enhance biodiversity within an agricultural landscape (Fischer et al. 2008). Koh et al. (2009) proposed a harmonization of both approaches to design landscapes threatened by biofuel expansion based on optimal requirements for sustaining biodiversity, economic and livelihood needs. Agroforestry (wildlife-friendly farming) zones around HCV areas can be used as corridors to connect surrounding fragments of HCV forests, act as buffer zones to mitigate human encroachment into HCVs and reduce edge and matrix effects from the intensively cultivated biofuel feedstock landscape (land sparing). How effective such an approach would be has yet to be tested in the field but offers a possibility for biofuel plantations to be developed in biodiversity hotspots. The importance of engagement with local stakeholders and support from local authorities cannot be stressed further as biodiversity conservation in biodiversity hotspots as mentioned throughout this chapter involve developing nations such as Brazil and Indonesia where rural development and improvement of people�s lives are an urgent priority.
X.4. CONCLUSION
Direct conversion of natural habitats in biodiversity hotspots into agricultural landscapes for biofuel feedstocks is the biggest threat arising from biofuel expansion. There is an urgent need to recognize that all biofuel plantations we reviewed in this chapter are depauperate in biodiversity compared to the natural habitats they replace. Other biofuel feedstocks such as Jatropha and cassava were not explored as there currently exists little research regarding these biofuel crops and their impacts on the environment. Although there are several proposals to reconcile biodiversity conservation with biofuel expansion, these suggestions are still limited in the extent of biodiversity which can be preserved compared to previous natural habitats. Policy-makers need to be very aware of how biofuel policies in their countries have the potential to do more harm than good should biofuel production occur at the expense of the world�s most biodiverse habitats. Unfortunately, the impact of biofuels is further complicated by the fact that these first generation biofuel feedstocks (soybean, sugarcane and palm oil) are also important global commodities. Rises in commodity prices as a result of biofuel policies can also trigger expansion on the agricultural front regardless of whether the end use of these commodities is for food, feed or fuel. Hence, emphasis on multi-stakeholder collaboration to produce biofuels sustainably and to ensure the protection of remaining natural habitats in biodiversity hotspots is the best immediate remediation to the expansion of biofuels in biodiversity hotspots.