Annual Energy Crops Research Articles

The factors determining uptake of energy crop cultivation and woodland creation in England: Insights from farmers and landowners

Perennial energy crops (PECs) and trees have key roles to play in delivering the negative emissions needed for the UK to reduce greenhouse gas emissions to net zero by 2050. Significant changes to land use are needed and the decision to make changes will lie with individual landowners. Using in-depth, semi-structured interviews, this research explores the attitudes of farmers and landowners in England to replacing traditional arable and livestock farming with growing annual or perennial energy crops or planting trees. It was concluded that considerable government policy intervention will be needed to overcome the many economic and social barriers in place including lack of markets and attractive contracts for growers, high establishment costs, loss of annual income, high prices available for cereal crops and the cultural division between farming and forestry. Although energy crops and woodland creation are generally researched and regulated separately, this research suggests that annual energy crops, PECs and woodland creation form a spectrum of land use options for a landowner, with the propensity to adopt these crops being determined predominantly by crop attributes including the risk of planting and the term of commitment.

Effects of Selected Annual and Perennial Energy Crops on Lumbricidae Community Assemblages

Effects of Selected Annual and Perennial Energy Crops on Lumbricidae Community Assemblages

Nematode abundances and community diversity under energy crop (maize and sainfoin) cultivation in annual and perennial cropping systems

Despite conservation efforts and increased awareness, the loss of soil biodiversity goes on across a wide range of ecosystems. Since soil function and structure depend mainly on the state of the biological communities, the soil quality assessment and disturbance in annual vs. perennial cropping systems is done with the help of indicators such as nematodes. Agricultural practices like mix cropping causes variations in the taxonomic abundance of soil nematode communities. This field experiment aimed to assess the overall effect of annual and perennial energy crops (maize: Zea mays and sainfoin: Onobrychis viciifolia) on the nematode communities under pure and mixed cultivation. Sainfoin had the highest nematode abundance, followed by the mixed culture and maize. Out of 38 identified genera, 19 were identified under maize, 31 under perennial sainfoin, 28 under annual sainfoin, 28 under perennial mixture, 20 under the annual mixture and 13 co-existed among these treatments. Of all the trophic groups, the bacterivores were the most abundant (738), followed by plant-parasitic nematodes (272), omnivores (230), fungivores (84), and carnivores (33). Nematode abundance was lower under the annual than perennial plots of both sainfoin and the mixed culture. The perennial plots were dominated by plant-parasitic nematodes. Our results support the idea that soil nematodes should be considered for inclusion in indices of soil quality through their contribution to soil processes. Also, soil nematodes and energy crops like sainfoin may increase the functional properties of agricultural ecosystems and allow better productivity and sustainability.

Assessment of Earthworm Services on Litter Mineralisation and Nutrient Release in Annual and Perennial Energy Crops (Zea mays vs. Silphium perfoliatum)

Abundant and functionally diverse earthworm communities in perennials deliver ecosystem services like increasing nutrient availability by incorporating organic matter. This study aimed to analyse the decomposition of annual and perennial energy crop residues, and the subsequent nutrient release, depending on earthworm functional diversity. In a laboratory experiment, two ecological earthworm groups—anecics (detritivorous Lumbricus terrestris (L.)) and endogeics (geophagous Aporrectodea caliginosa and A. rosea)—were incubated with wilted cup plant (Silphium perfoliatum) and maize (Zea mays) litter for 4 or 8 weeks. Decomposition and consumption rates were calculated. The C, N and P in litter and casts were analysed. Mineralisation was a function of earthworm biomass and the number of individuals. Functional diversity had no beneficial effect. Decomposition was found to be highest in treatments with detritivorous earthworms, i.e., higher earthworm biomass, yet consumption and nutrient turnover in relation to earthworm biomass were higher in treatments with geophages indicating enhanced competition. N limitation became apparent in both litter treatments and was predominant with cup plant litter. N limitation and recalcitrant cell wall compounds affected consumption rates and the egestion of total C and P. While N in casts was lower than expected, P was increased. We observed that the effects manifested at different stages of decomposition of maize and cup plant, highlighting differences in temporal development of decomposition and nutrient turnover between litter types. Our results indicate that earthworms promote decomposition of recalcitrant litter and nutrient turnover, but N limitation may hamper nutrient release. Cup plant systems offer a suitable habitat for soil-dwelling organisms, but management approaches must consider the adequate input of organic matter as an energy and nutrient source to enhance ecosystem service provision.

The effects of periodically stagnant soil water conditions on biomass and methane yields of Silphiumperfoliatum

Resulting from the wide range of usages of bio-methane, anaerobic digestion has become a major issue. Beside biogenic residues, the cultivation of energy crops has significantly been expanded in Europe. Due to the increasing competition for land, sites with a low value for food production are predestined for cultivating feedstocks. Numerous studies have shown that perennial energy crops (PECs) present a valuable alternative to annual energy crops since they combine sound energy yields with substantial ecological advantages. Particularly under unprivileged sites conditions, PECs may fully leverage their strengths. Soils showing long lasting periods of soil moisture above field capacity (Stagnosols) were evaluated to be critical for silage maize cultivation as heavy harvest machinery may cause severe soil damages. Additionally, juvenile development of maize suffers from stagnant soil water.This study aimed to verify the results of a former pot experiment in which cup plant (Silphium perfoliatum) showed early sprouting, fast biomass development and higher yields under a soil water regime typical for Stagnosols. Thus, in the presented field experiment, silage maize and cup plant, were cultivated on well-drained soils (Cambisols) and on Stagnosols, and were compared concerning biomass and energy yields.On Stagnosols, the cup plant benefited likely from the higher soil water availability and produced average biomass yields of 14.3 t ha−1 a−1 being about 40% higher than on well-drained soils. The biochemical methane potential was 305 LN kg−1 VS and not affected by the soil type. Nonetheless, the methane yields per area of cup plant were still 35% lower than those of silage maize.

Different life‐form strategies of perennial energy crops and related nutrient exports require a differentiating view specifically concerning a sustainable cultivation on marginal land

AbstractPerennial energy crops (PECs) are increasingly used as feedstock to produce energy in an environmental friendly way. Compared to traditional conversion strategies like thermal use, sophisticated technologies such as biomethanation defined different requirements of the feedstock. Whereas the first concept relies on dry, woody material, biomethanation requires a moist feedstock. Thus, over time, the spectrum of species used as PECs has widened. Moreover, harvest dates were adjusted to provide the feedstock at suitable moisture contents. It is well known that perennial, lignocellulose‐based energy crops, compared to annual, sugar‐ and starch‐based ones, offer ecological advantages such as, inter alia, improving biodiversity in landscape, protecting soil against erosion, and protecting groundwater from nutrient inputs. However, one of the main arguments for PEC cultivation was their undemanding nature concerning external inputs. With respect to the broader spectrum of PEC species and changed harvest dates, the question arises whether the concept of PECs being low‐input energy crops is still valid. This also implies the question of suitable growing conditions and sustainable management. The aims of this opinion paper were to classify different PECs according to their life‐form strategy, compare nutrient exports when harvested in different maturation stages, and to discuss the results in the context of sustainable PEC cultivation on marginal land. This study revealed that nutrient exports with yield biomass of PECs harvested in green state are in the same range than those of annual energy crops and therewith several times higher than those of PECs harvested in brown state or of woody short rotation coppices. Thus, PECs cannot universally be claimed as low‐input energy crops. These results also imply the consequences of cultivation of PECs on marginal land. Finally, the question has to be raised whether the term PECs should prospectively be better specified in written and spoken words.

Estimation of the Biochar Effect on Annual Energy Crops Grown in Post-Mining Lands

Estimation of the Biochar Effect on Annual Energy Crops Grown in Post-Mining Lands

Soil organic carbon allocation and dynamics under perennial energy crops and their feedbacks with soil microbial biomass and activity

AbstractThe cultivation of perennial instead of annual energy crops has received growing interest. Previous studies identified numerous beneficial effects of perennial energy crop (PEC) cultivation for the agricultural landscape such as promotion of agrobiodiversity, reduced requirements for agrochemicals and fertilizers as well as a large potential for carbon accumulation in soil. However, the mere presence of soil organic matter (SOM) accumulation gives no indication about the persistence of the SOM for example after a recultivation of the stands. Therefore, this study focused on SOM pools of different density fractions and soil microbial parameters. Six different PECs were tested against a typical benchmark system as feedstock for anaerobic digestion. The study has shown that all PEC species increased soil microbial activity and provided an insight how they sequester carbon in soil. Moreover, significant modifications in basic soil properties caused by plant growth were observed. For example, the cultivation of giant knotweed has lowered the soil pH by more than 0.5 pH units compared to the benchmark system. After 5 years of PEC cultivation, total soil organic carbon stocks were increased between 1,500 ± 400 and 4,500 ± 1,500 kg C ha‐1 for the upper 10 centimetres of soil. The distribution among different soil fractions showed species‐specific patterns. Tall wheatgrass and Virginia mallow showed particular high accumulation rates in the mineral‐associated SOM fraction which indicates long residence times of the SOM after a possible recultivation of the fields.

Modelling dynamic soil organic carbon flows of annual and perennial energy crops to inform energy-transport policy scenarios in France

Low carbon strategies recently focus on soil organic carbon (SOC) sequestration potentials from agriculture and forestry, while Life Cycle Assessment (LCA) increasingly becomes the framework of choice to estimate the environmental impacts of these activities. Classic LCA is limited to static carbon neutral approaches, disregarding dynamic SOC flows and their time-dependent GHG contributions. To overcome such limitation, the purpose of this study is to model SOC flows associated with agricultural land use (LU) and the provision of agricultural substrates to transport biofuels, thus generating dynamic inventories and comparatively assessing energy policy scenarios and their climate consequences in the context of dynamic LCA. The proposed framework allows computing SOC from annual and perennial species under specific management practices (e.g. residue removal rates, organic fertiliser use). The results associated with the implementation of three energy policies and two accounting philosophies (C-neutral and C-complete) show that shifting energy pathways towards advanced biofuels reduces overall resource consumption, LU and GHG emissions. The French 2015 Energy Transition for Green Growth Act (LTECV) leads towards higher mitigation targets compared with business-as-usual (BAU) and intermediate (15BIO) policy constraints. C-neutral results show reduced radiative forcing effects by 10% and 34% for 15BIO and LTECV respectively, with respect to BAU. C-complete (i.e. dynamic assessment of all biogenic- and fossil-sourced C flows) results reveal further mitigation potentials across policies, whereof 50%-65% can be attributed to temporal C sequestration in perennial rhizomes. A sensitivity analysis suggests important SOC variations due to temperature increase (+2°C) and changes in residue removal rates. Both parameters affect mitigation and the latter also LU, by a factor of −0.56 to + 5. This article highlights the importance of SOC modelling in the context of LU in LCA, which is usually disregarded, as SOC is considered only in the context of land use change (LUC).

Quantifying the climate change effects of bioenergy systems: Comparison of 15 impact assessment methods

AbstractOngoing concern over climate change has led to interest in replacing fossil energy with bioenergy. There are different approaches to quantitatively estimate the climate change effects of bioenergy systems. In the present work, we have focused on a range of published impact assessment methods that vary due to conceptual differences in the treatment of biogenic carbon fluxes, the type of climate change impacts they address and differences in time horizon and time preference. Specifically, this paper reviews fifteen different methods and applies these to three hypothetical bioenergy case studies: (a) woody biomass grown on previously forested land; (b) woody biomass grown on previous pasture land; and (b) annual energy crop grown on previously cropped land. Our analysis shows that the choice of method can have an important influence on the quantification of climate change effects of bioenergy, particularly when a mature forest is converted to bioenergy use as it involves a substantial reduction in biomass carbon stocks. Results are more uniform in other case studies. In general, results are more sensitive to specific impact assessment methods when they involve both emissions and removals at different points in time, such as for forest bioenergy, but have a much smaller influence on agricultural bioenergy systems grown on land previously used for pasture or annual cropping. The development of effective policies for climate change mitigation through renewable energy use requires consistent and accurate approaches to identification of bioenergy systems that can result in climate change mitigation. The use of different methods for the same purpose: estimating the climate change effects of bioenergy systems, can lead to confusing and contradictory conclusions. A full interpretation of the results generated with different methods must be based on an understanding that the different methods focus on different aspects of climate change and represent different time preferences.

A land-based approach for the environmental assessment of Mediterranean annual and perennial energy crops

Abstract Biomass production helps address the worldwide energy demand. However, some controversial issues have been identified such as the possible conflict between the goal of increasing vegetable biomass and food production and the need to limit environmental impacts. In Mediterranean region, where the supply of some natural resources appears significantly limited (e.g., water) and the competition for land is higher than it was in the past, the objective of evaluating environmental burdens at a regional scale represents an important issue, especially if the assessment considers the farmer scope of increasing productivity. Using a Life Cycle Assessment (LCA) “from cradle to field gate” approach, this paper aims to evaluate land-based environmental sustainability related to four energy crop options. We carried out a LCA differentiating between annual and perennial species and between irrigated (giant reed and sorghum) and rainfed crops (cardoon and milk thistle) to determine their performances and impacts within the same context. The findings suggest that irrigated crops generate larger impacts on the environment than rainfed species and that annual crops (both irrigated and rainfed) are more damaging than the respective perennial crops. The damages were expressed in Ecopoints, where one Ecopoint corresponds to one thousandth of the annual overall environmental burden of an average European inhabitant. Ecopoints for sorghum, giant reed, milk thistle and cardoon are equal to 361, 288, 146, and 138, respectively. Except for irrigation, fertilizers were found to be the input with the largest effect, accounting for 37% (giant reed) to 75% (cardoon) of the environmental burden on the system. The results do not suggest the presence of a winning crop option – i.e., a crop that shows the best environmental performances everywhere and in all categories – since regional environmental burdens are simultaneously related to different factors (e.g., land allocation, crop productivity, and degree of practice intensification) that drive farmer choice. Finally, following a dynamic and innovative perspective, we evaluated the trade-off between productivity and environmental burden for each crop simulating an increasing product variation. We found that environmental burdens would increase more proportionally than crop yields done. Especially the latter finding provides interesting suggestions on energy cropping system integration within agricultural planning under stressed natural resource conditions.

Co-design and ex ante assessment of cropping system prototypes including energy crops in Eastern France

Producing biofuels from crops is controversial due to environmental issues and to food security threats linked with the dedication of land to energy crops rather than to food production. The 2009 European Renewable Energy Directive defined the reduction of greenhouse gas (GHG) emissions as an essential requirement for biofuels. Whatever their specific lifespans, energy crops have short- and long-term effects on the following crops, thus requiring assessment at cropping system level, which is rarely done in the literature.This study aimed at designing and assessing cropping system prototypes (CSP) that include energy crops and food/feed crops in Bourgogne (France), before being implemented in the field (i.e. ex ante). CSP were first designed, using a prototyping approach involving scientists and farm advisors, and then ex ante assessed, using indicators covering the environment, energy, economic and food issues. They were compared with two cropping systems based on food/feed crops. Lastly, we analyzed the sensitivity of the CSP profitability to several scenarios of crop yields and prices (i.e. grain and forage prices for food and feed crops respectively).CSP including Miscanthus x giganteus performed better in terms of GHG emissions, energy costs, nitrate losses and pesticide use than CSP that include only annual crops requiring more inputs, but achieved lower profitability and food production capacity. The cropping systems including only food/feed crops frequently achieved higher economic outcomes and food production capacity. Lastly, CSP combining pluriannual or annual energy crops and annual food/feed crops showed satisfactory trade-offs among environmental impacts and food production capacity.

Soil quality indicator response to land‐use change from annual to perennial bioenergy cropping systems in Germany

AbstractProduction of biomass feedstock for methanation in Europe has focused on silages of maize and cereals. As ecological awareness has increased in the last several years, more attention is being focused on perennial energy crops (PECs). Studies of specific PECs have shown that their cultivation may enhance agrobiodiversity and increase soil organic carbon stocks while simultaneously providing valuable feedstock for methanation. This study was designed to compare soil quality indicators under annual energy crops (AECs), PECs and permanent grassland (PGL) on the landscape level in south‐western Germany. At a total 25 study sites, covering a wide range of parent materials, the cropping systems were found adjacent to each other. Stands were commercially managed, and PECs included different species such as the Cup Plant, Tall Wheatgrass, Giant Knotweed, Miscanthus, Virginia Mallow and Reed Canary Grass. Soil sampling was carried out for the upper 20 cm of soil. Several soil quality indicators, including soil organic carbon (Corg), soil microbial biomass (Cmic), and aggregate stability, showed that PECs were intermediate between AEC and PGL systems. At landscape level, mean Corg content for (on average) 6.1‐year‐old stands of PEC was 22.37 (±7.53) g kg−1, compared to 19.23 (±8.08) and 32.08 (±10.11) for AEC and PGL. Cmic contents were higher in PECs (356 ± 241 μg C g−1) compared to AECs (291 ± 145) but significantly lower than under PGL (753 ± 417). The aggregate stability increased by almost 65% in PECs compared to AEC but was still 57% lower than in PGL. Indicator differences among cropping systems were more pronounced when inherent differences in the parent material were accounted for in the comparisons. Overall, these results suggest that the cultivation of PECs has positive effects on soil quality indicators. Thus, PECs may offer potential to make the production of biomass feedstock more sustainable.

Impact of newly introduced perennial bioenergy crops on soil quality parameters at three different locations in W‐Germany

AbstractThe land areas used for bioenergy crop cultivation are increasing across Europe. For several years now, various perennial crops have been cultivated, including Miscanthus, switchgrass and reed canary grass, and the newly introduced cup plant, giant knotweed, tall wheatgrass, virginia mallow, and wild plant mixtures. We investigated the impact that many of these perennial bioenergy crops (PECs) have on the soil organic C and N pools, microbial properties, and earthworm activity at three different study sites in W‐Germany with varying soil conditions after an experimental period of five years. Silage maize (Zea maize) in rotation with green rye (Cecale cereale) or Triticale was used for comparison (= annual energy crops; AEC). The overall intention of this study was to gain insights into the future trends of soil quality with changes in land‐use towards bioenergy production. Our results emphasized that in general, soil quality was improved through the cultivation of perennials. For example, after five years of investigation, the mean soil organic carbon contents increased, on average, by 1–2% at two of the three study sites, the soil microbial biomass increased from 13% (virginia mallow) to 27% (tall wheatgrass) (p < 0.05) compared to AEC treatment and the mean earthworm activity (cast production) was significantly improved in PECs compared to AEC. These trends were mainly found in silty to loamy soils, but the results were slightly different in sandy soils and dry climate conditions. We suggest that this might be traced back to unfavourable growing conditions for perennial crops during the first years of establishment. To our knowledge, this is the first comprehensive field investigation of the impact of these newly introduced perennial crops on soil quality indicators that considers various site‐ and soil‐specific growth conditions.

Yields of Annual and Perennial Energy Crops in a 12‐year Field Trial

Core Ideas A long‐term field trial of important perennial and annual energy crops was conducted. Maize is most high yielding of biomass with high N inputs. Miscanthus is most high yielding of biomass without or with moderate N inputs. In crop rotations, no‐till practice with less input does not reduce the productivity. Nitrogen input is more important in annuals than perennials to maintain the yield level. To find an energy cropping system with low input and high productivity, a 12‐yr field trial was conducted in Southwest Germany with perennial crops, and monocropping or rotation of annual crops. The perennials were willow (Salix schwerinii E. Wolf × viminalis L.) short rotation coppice, miscanthus (Miscanthus × giganteus Greef et Deu.), and switchgrass (Panicum virgatum L.). The monocropped annual was maize (Zea mays L.), and the rotation was oilseed rape (Brassica napus L. ssp. oleifera)–wheat (Triticum aestivum L.)–triticale (Triticale × triticosecale Wittmack). The rotation was split into tillage with moldboard plow or no‐till. These systems were implemented with three N fertilization levels. Annual yield trend in years, accumulated yields of biomass, and gross energy were compared across N levels between perennials and annuals, and between tillage managements. Among these cropping systems, maize (18.5 Mg ha−1 yr−1) and miscanthus (18.3 Mg ha−1 yr−1) were most productive. Without N fertilization, miscanthus was most productive (13.6 Mg ha−1 yr−1). In the long run, N fertilization significantly increased the yields of all systems. The long‐term yield trends of the perennials were relatively stable, while the annuals without N fertilization showed a prevailing trend of yield decrease. No‐till did not significantly lower the yield compared to plowing (8.7 vs. 9.3 Mg ha−1 yr−1). Generally, the perennial systems produced higher gross energy yield compared to the annual systems under comparable N fertilizations. Particularly miscanthus gained high yields even with moderate to no N inputs.

Miscanthus as biogas substrate – cutting tolerance and potential for anaerobic digestion

AbstractIn the anaerobic digestion and biogas industry in Germany, the step of energy crop production accounts for a high proportion of the greenhouse gas emissions and environmental impacts. Replacing annual energy crops, for example maize, by perennial biomass crops such as miscanthus offers the potential to increase the sustainability of biogas crop production. However, the cutting tolerance of miscanthus and the mechanisms influencing it need to be investigated to assess its potential as a biogas crop. For this purpose, a field trial with different harvest regimes was conducted to identify the potential methane yield and cutting tolerance of Miscanthus x giganteus. Several fertilization regimes were tested under nitrogen‐limited conditions in a pot trial to investigate the mechanisms behind the cutting tolerance. The refilling of carbohydrate (starch) stores in the rhizome was identified as a very important factor influencing the cutting tolerance of miscanthus, whereas the nutrient relocation appeared to be of less importance. The field trial revealed that Miscanthus x giganteus offers a very high methane yield potential of approx. 6000 m3 ha−1 when harvested in October, which is within the range of the methane hectare yield of energy maize. The substrate‐specific methane yield of Miscanthus x giganteus biomass decreased with later harvest dates and reached 247 ml (g oDM)−1 in October. This harvest date delivered very high, stable yields of on average 26 t DM ha−1 over two years and enabled a good cutting tolerance. Green harvest in October was identified to be suitable for Miscanthus x giganteus and is recommended for biogas utilization. In conclusion, the perennial biomass crop Miscanthus x giganteus is a very promising biogas crop and offers the potential to increase the sustainability of the anaerobic digestion sector in Germany by replacing a substantial area of biogas maize cultivation.

Group-based crop change planning: Application of SmartScape™ spatial decision support system for resolving conflicts

Agricultural changes are complex and managing an appropriate type of crop change to satisfy stakeholders with various interests is challenging. Decisions regarding a crop change need to be debated among multiple stakeholders with various conflicting viewpoints. Two kinds of conflicts might occur as a result of crop change in an agricultural landscape: (1) conflicts among multiple ecosystem services i.e., internal conflicts and (2) conflicts among multiple stakeholders i.e., external conflicts. While a spatial decision support system (SDSS) can provide answers concerning multifaceted problems, there are currently a few SDSSs that indicate the trade-offs among multiple ecosystem services as a result of crop change and also enable stakeholders with diverse preferences to arrive at group-based decisions. In this study, we held a series of meetings with stakeholders, who were experts in economics, energy, soil erosion, greenhouse gas emission, surface water, and biodiversity, to develop two crop change scenarios by replacing perennial energy crops with annual energy crops and vice versa. We then used an online SDSS, SmartScape™, and applied it to Dane county, Wisconsin, U.S. to (1) run the two aforementioned crop change scenarios separately in order to assess how effectively SmartScape™ enables decision makers to resolve internal conflicts while considering the relative values of multiple ecosystem services, and (2) run the two crop change scenarios jointly to show how well SmartScape™ enables decision makers to resolve external conflicts in a group while taking into account the diverse goals of stakeholders. The outcomes of this study can inform policy-makers about both internal conflicts within a crop change scenario and external conflicts among stakeholders and provide a unique framework to resolve both types of conflict in an effective way. Obtaining acceptable crop change solutions among stakeholders with conflicting interests can lead us in moving from individual decision-making to group-based decision-making so that we can enhance sustainability in agricultural landscapes.

Analyzing crop change scenario with the SmartScape™ spatial decision support system

Agricultural land use is increasingly changing due to different anthropogenic activities. A combination of economic, socio-political, and cultural factors exerts a direct impact on agricultural changes. This study aims to illustrate how stakeholders and policymakers can take advantage of a web-based spatial decision support system (SDSS), namely SmartScape™ to either test existing crop change policies or produce effective crop change decisions using tradeoff analysis. We addressed the consequences of two common crop change scenarios for Dane county in Wisconsin, United States, (a) replacing perennial energy crops with annual energy crops and (b) replacing annual energy crops with perennial energy crops. The results suggested that converting areas under grass and alfalfa production that were located on high quality soil and flat slope to corn promoted a net-income and availability of gross biofuel. Additionally, the model outcome proposed that converting areas under corn and soy production that were located on high slope to grass promoted net-energy, phosphorus loading, soil loss, soil carbon sequestration, nitrous oxide emission, grassland bird habitat, pollinator abundance, and biocontrol. Therefore, SmartScape™ can assist strategic crop change policy by comparing the tradeoff among ecosystem services to ensure that crop change policies have outcomes that are agreeable to a diversity of policymakers.

Potential job creation in the cellulosic biofuel industry: the effect of feedstock price

AbstractA large‐scale biofuel industry based on cellulosic materials would provide many new job opportunities. We model potential direct jobs generated by a cellulosic ethanol industry in the United States. These job projections are estimated via a bottom‐up approach based on the cellulosic feedstock supply chain systems as a function of the price farmers receive for the feedstock. The cellulosic feedstock types involved in the feedstock supply chain system are crop residues, perennial grasses, annual energy crops, and coppiced and non‐coppiced woody crops. Results show that the feedstock transportation sector is where most of the jobs are created, followed by the feedstock production sector. Jobs generated by the feedstock transportation sector account for around one‐third of total new jobs generated, while jobs generated by cellulosic feedstock production account for about one‐quarter of the new jobs. In the United States, most of the new jobs are created in Iowa, Kansas, Missouri, Oklahoma, and Texas. At feedstock prices over US$ 55 per dry ton, more than 100 000 new direct full‐time equivalent jobs are potentially generated. The number of jobs potentially generated by the cellulosic ethanol fuel production system is highly sensitive to the feedstock price. At $60 per ton, a 50% increase in feedstock price, the system generates over 6 times more jobs than it does at a feedstock price of $40 per ton. Many more farmers produce cellulosic feedstock for ethanol production at higher feedstock prices, and thus more ethanol production leads to more job creation. © 2015 Society of Chemical Industry and John Wiley & Sons, Ltd

Pesticide runoff from energy crops: A threat to aquatic invertebrates?

The European Union aims to reach a 10% share of biofuels in the transport sector by 2020. The major burden is most likely to fall on already established annual energy crops such as rapeseed and cereals for the production of biodiesel and bioethanol, respectively. Annual energy crops are typically cultivated in intensive agricultural production systems, which require the application of pesticides. Agricultural pesticides can have adverse effects on aquatic invertebrates in adjacent streams. We assessed the relative ecological risk to aquatic invertebrates associated with the chemical pest management from six energy crops (maize, potato, sugar beet, winter barley, winter rapeseed, and winter wheat) as well as from mixed cultivation scenarios.The pesticide exposure related to energy crops and cultivation scenarios was estimated as surface runoff for 253 small stream sites in Central Germany using a GIS-based runoff potential model. The ecological risk for aquatic invertebrates, an important organism group for the functioning of stream ecosystems, was assessed using acute toxicity data (48-h LC50 values) of the crustacean Daphnia magna. We calculated the Ecological Risk from potential Pesticide Runoff (ERPR) for all three main groups of pesticides (herbicides, fungicides, and insecticides). Our findings suggest that the crops potato, sugar beet, and rapeseed pose a higher ecological risk to aquatic invertebrates than maize, barley, and wheat. As maize had by far the lowest ERPR values, from the perspective of pesticide pollution, its cultivation as substrate for the production of the gaseous biofuel biomethane may be preferable compared to the production of, for example, biodiesel from rapeseed.