Traffic lights for crop-based biofuels

This editorial was written while the author was a Raymond and Beverly Sackler research fellow at Churchill College, Cambridge, working on research funded by the Isaac Newton Trust and the RSPB. He assumes all responsibility for the opinions expressed. No writing assistance was utilized in the production of this manuscript.This is the submitted version of the article. The final version is available at http://www.future-science.com/doi/abs/10.4155/bfs.10.83

Agriculture as a key element for conservation: Reasons for caution

This is the pre-peer reviewed version of the following article: Phalan B., Balmford A. & Green R. E. (2012) Agriculture as a key element for conservation: reasons for caution. Conservation Letters 5: 323–324 which has been published in final form at: http://onlinelibrary.wiley.com/doi/10.1111/j.1755-263X.2012.00248.x/abstrac

The potential for land sparing to offset greenhouse gas emissions from agriculture

Greenhouse gas emissions from global agriculture are increasing at around 1% per annum, yet substantial cuts in emissions are needed across all sectors. The challenge of reducing agricultural emissions is particularly acute, because the reductions achievable by changing farming practices are limited and are hampered by rapidly rising food demand. Here we assess the technical mitigation potential offered by land sparing-increasing agricultural yields, reducing farm land area and actively restoring natural habitats on the land spared. Restored habitats can sequester carbon and can offset emissions from agriculture. Using the United Kingdom as an example, we estimate net emissions in 2050 under a range of future agricultural scenarios. We find that a land-sparing strategy has the technical potential to achieve significant reductions in net emissions from agriculture and land-use change. Coupling land sparing with demand-side strategies to reduce meat consumption and food waste can further increase the technical mitigation potential, however economic and implementation considerations might limit the degree to which this technical potential could be realised in practice.This research was funded by the Cambridge Conservation Initiative Collaborative Fund for Conservation and we thank its major sponsor Arcadia. We thank J. Bruinsma for the provision of demand data, the CEH for the provision of soil data and J. Spencer for invaluable discussions. A.L. was supported by a Gates Cambridge Scholarship.This is the author accepted manuscript. The final version is available from Nature Publishing Group via http://dx.doi.org/10.1038/nclimate291

Impacts of climate change on plant diseases – opinions and trends

There has been a remarkable scientific output on the topic of how climate change is likely to affect plant diseases in the coming decades. This review addresses the need for review of this burgeoning literature by summarizing opinions of previous reviews and trends in recent studies on the impacts of climate change on plant health. Sudden Oak Death is used as an introductory case study: Californian forests could become even more susceptible to this emerging plant disease, if spring precipitations will be accompanied by warmer temperatures, although climate shifts may also affect the current synchronicity between host cambium activity and pathogen colonization rate. A summary of observed and predicted climate changes, as well as of direct effects of climate change on pathosystems, is provided. Prediction and management of climate change effects on plant health are complicated by indirect effects and the interactions with global change drivers. Uncertainty in models of plant disease development under climate change calls for a diversity of management strategies, from more participatory approaches to interdisciplinary science. Involvement of stakeholders and scientists from outside plant pathology shows the importance of trade-offs, for example in the land-sharing vs. sparing debate. Further research is needed on climate change and plant health in mountain, boreal, Mediterranean and tropical regions, with multiple climate change factors and scenarios (including our responses to it, e.g. the assisted migration of plants), in relation to endophytes, viruses and mycorrhiza, using long-term and large-scale datasets and considering various plant disease control methods

To what extent could edge effects and habitat fragmentation diminish the potential benefits of land sparing?

Land sharing and land sparing are contrasting proposals for minimising the impacts of agriculture on wild species. Edge effects (biophysical gradients near habitat boundaries) might reduce population sizes on spared land, particularly in highly-fragmented landscapes, so might change conclusions about whether land sparing or land sharing is better for species' persistence. We assessed this possibility by modelling the population sizes of 120 Ghanaian bird species in the presence of a range of hypothetical edge effects under land-sparing and land-sharing strategies, and at different levels of habitat fragmentation and agricultural production. We found that edge effects can reduce population densities on spared land, and in highly-fragmented landscapes can - at modest levels of agricultural production combined with high edge penetration distances - cause the optimal strategy to switch from land sparing to land sharing. Nevertheless, land sparing maximised population sizes for more species in most cases tested. This conclusion was best supported for sensitive species with small global geographical ranges, which are likely to include those of greatest future conservation concern. The size of patches of spared land affected conservation outcomes: population sizes were maximised under a land-sparing strategy that spared large blocks of natural habitat of ~ 1000 or, better, ~ 10,000 ha. To effect land sparing in practice would require policies that promoted both increases in agricultural yield and the establishment or protection of natural habitats on spared land. Because the optimum scale of patches of spared land for edge-sensitive species is generally larger than the size of individual farms, policies that facilitate coordinated action by farmers or other land managers might be required.A.L. was funded by a Gates Cambridge Scholarship

Biodiversity scientists must fight the creeping rise of extinction denial

Efforts by conservation scientists to draw public attention to the biodiversity crisis are increasingly met with denialist rhetoric. We summarize some of the methods used by denialists to undermine scientific evidence on biodiversity loss, and outline pathways forward for the scientific community to counter misinformation

An agenda for integrated system-wide interdisciplinary agri-food research

© 2017 The Author(s)This paper outlines the development of an integrated interdisciplinary approach to agri-food research, designed to address the ‘grand challenge’ of global food security. Rather than meeting this challenge by working in separate domains or via single-disciplinary perspectives, we chart the development of a system-wide approach to the food supply chain. In this approach, social and environmental questions are simultaneously addressed. Firstly, we provide a holistic model of the agri-food system, which depicts the processes involved, the principal inputs and outputs, the actors and the external influences, emphasising the system’s interactions, feedbacks and complexities. Secondly, we show how this model necessitates a research programme that includes the study of land-use, crop production and protection, food processing, storage and distribution, retailing and consumption, nutrition and public health. Acknowledging the methodological and epistemological challenges involved in developing this approach, we propose two specific ways forward. Firstly, we propose a method for analysing and modelling agri-food systems in their totality, which enables the complexity to be reduced to essential components of the whole system to allow tractable quantitative analysis using LCA and related methods. This initial analysis allows for more detailed quantification of total system resource efficiency, environmental impact and waste. Secondly, we propose a method to analyse the ethical, legal and political tensions that characterise such systems via the use of deliberative fora. We conclude by proposing an agenda for agri-food research which combines these two approaches into a rational programme for identifying, testing and implementing the new agri-technologies and agri-food policies, advocating the critical application of nexus thinking to meet the global food security challenge

Social-ecological outcomes of agricultural intensification

Land-use intensification in agrarian landscapes is seen as a key strategy to simultaneously feed humanity and use ecosystems sustainably, but the conditions that support positive social-ecological outcomes remain poorly documented. We address this knowledge gap by synthesizing research that analyses how agricultural intensification affects both ecosystem services and human well-being in low- and middle-income countries. Overall, we find that agricultural intensification is rarely found to lead to simultaneous positive ecosystem service and well-being outcomes. This is particularly the case when ecosystem services other than food provisioning are taken into consideration

Annual and seasonal movements of migrating short-tailed shearwaters reflect environmental variation in sub-Arctic and Arctic waters

The marine ecosystems of the Bering Sea and adjacent southern Chukchi Sea are experiencing rapid changes due to recent reductions in sea ice. Short-tailed shearwaters Puffinus tenuirostris visit this region in huge numbers between the boreal summer and autumn during non-breeding season, and represent one of the dominant top predators. To understand the implications for this species of ongoing environmental change in the Pacific sub-Arctic and Arctic seas, we tracked the migratory movements of 19 and 24 birds in 2010 and 2011, respectively, using light-level geolocators. In both years, tracked birds occupied the western (Okhotsk Sea and Kuril Islands) and eastern (southeast Bering Sea) North Pacific from May to July. In August–September of 2010, but not 2011, a substantial proportion (68 % of the tracked individuals in 2010 compared to 38 % in 2011) moved through the Bering Strait to feed in the Chukchi Sea. Based on the correlation with oceanographic variables, the probability of shearwater occurrence was highest in waters with sea surface temperatures (SSTs) of 8–10 °C over shallow depths. Furthermore, shearwaters spent more time flying when SST was warmer than 9 °C, suggesting increased search effort for prey. We hypothesized that the northward shift in the distribution of shearwaters may have been related to temperature-driven changes in the abundance of their dominant prey, krill (Euphausiacea), as the timing of krill spawning coincides with the seasonal increase in water temperature. Our results indicate a flexible response of foraging birds to ongoing changes in the sub-Arctic and Arctic ecosystems

Avoiding impacts on biodiversity through strengthening the first stage of the mitigation hierarchy

AbstractThe mitigation hierarchy is a decision-making framework designed to address impacts on biodiversity and ecosystem services through first seeking to avoid impacts wherever possible, then minimizing or restoring impacts, and finally by offsetting any unavoidable impacts. Avoiding impacts is seen by many as the most certain and effective way of managing harm to biodiversity, and its position as the first stage of the mitigation hierarchy indicates that it should be prioritized ahead of other stages. However, despite an abundance of legislative and voluntary requirements, there is often a failure to avoid impacts. We discuss reasons for this failure and outline some possible solutions. We highlight the key roles that can be played by conservation organizations in cultivating political will, holding decision makers accountable to the law, improving the processes of impact assessment and avoidance, building capacity, and providing technical knowledge. A renewed focus on impact avoidance as the foundation of the mitigation hierarchy could help to limit the impacts on biodiversity of large-scale developments in energy, infrastructure, agriculture and other sectors.This paper is a product of a project on strengthening the mitigation hierarchy for greater conservation gains, funded by the Cambridge Conservation Initiative Collaborative Fund. BP was funded by a Zukerman Fellowship at King’s College, Cambridge