• Energy Research
• 11. Sustainability close
• IT close
• University of Queensland close

AbstractAgriculture is the largest single source of environmental degradation, responsible for over 30% of global greenhouse gas (GHG) emissions, 70% of freshwater use and 80% of land conversion: it is the single largest driver of biodiversity loss (Foley JA, Science 309:570–574, 2005, Nature 478:337–342, 2011; IPBES. Global assessment report on biodiversity and ecosystem services of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services. IPBES Secretariat, Bonn, 2019; Willett W et al. The Lancet 393:447–492, 2019). Agriculture also underpins poor human health, contributing to 11 million premature deaths annually. While too many still struggle from acute hunger, a growing number of individuals, including in low to middle-income countries (LMICs), struggle to access healthy foods. Greater consideration for, and integration of, biodiversity in agriculture is a key solution space for improving health, eliminating hunger and achieving nature-positive development objectives.This rapid evidence review documents the best available evidence of agriculture’s relationships with biodiversity, drawing on the contributions of leading biodiversity experts, and recommends actions that can be taken to move towards more biodiversity/nature-positive production through the delivery of integrated agricultural solutions for climate, biodiversity, nutrition and livelihoods. The analysis, which takes a whole-of-food-system approach, brings together a large body of evidence. It accounts for aspects not typically captured in a stand-alone primary piece of research and indicates where there are critical gaps.

AbstractGovernments have committed to conserving ≥17% of terrestrial and ≥10% of marine environments globally, especially “areas of particular importance for biodiversity” through “ecologically representative” Protected Area (PA) systems or other “area‐based conservation measures”, while individual countries have committed to conserve 3–50% of their land area. We estimate that PAs currently cover 14.6% of terrestrial and 2.8% of marine extent, but 59–68% of ecoregions, 77–78% of important sites for biodiversity, and 57% of 25,380 species have inadequate coverage. The existing 19.7 million km2 terrestrial PA network needs only 3.3 million km2 to be added to achieve 17% terrestrial coverage. However, it would require nearly doubling to achieve, cost‐efficiently, coverage targets for all countries, ecoregions, important sites, and species. Poorer countries have the largest relative shortfalls. Such extensive and rapid expansion of formal PAs is unlikely to be achievable. Greater focus is therefore needed on alternative approaches, including community‐ and privately managed sites and other effective area‐based conservation measures.

Abstract Biomass-derived synthetic jet fuel with low net greenhouse gas emissions can help decarbonize aviation. Demonstration projects are required to show technical feasibility and give confidence to investors in large commercial-scale deployments. Most previous literature focuses on assessing future commercial-scale systems, for which performance and costs will differ considerably from demonstration projects. Here, a detailed analysis is presented for a first-of-a-kind demonstration plant that would be built in the Southeastern US. The plant, which cogasifies biomass and lignite and captures CO2 prior to Fischer-Tropsch synthesis, was designed and simulated using Aspen Plus. The process heat recovery system was designed using a systematic optimization method. Lifecycle analysis was used to assess net greenhouse gas emissions. Capital and operating cost estimates were developed in collaboration with a major engineering firm. The plant produces 1252 barrels per day (80% jet fuel), exports 15 MWe (net), and has a net energy efficiency of 35.8% (lower heating value). Captured CO2 (1326 t/d) is sold for use in enhanced oil recovery. With biomass coming from sustainably-managed pine plantations, net lifecycle greenhouse gas emissions are well below those for petroleum jet fuel. The estimated range of capital required to build the plant is 3875–5762 $/kWth of feedstock input (2015$). As expected for a small demonstration designed to minimize technological risks, subsidies are required for the jet fuel product to compete with petroleum jet fuel. Technology innovations, learning via construction and operating experience, and larger plant scales will improve the economics of future commercial plants.

AbstractThe ongoing agrarian transition from small-holder farming to large-scale commercial agriculture is reshaping systems of production and human well-being in many regions. A fundamental part of this global transition is manifested in large-scale land acquisitions (LSLAs) by agribusinesses. Its energy implications, however, remain poorly understood. Here, we assess the multi-dimensional changes in fossil-fuel-based energy demand resulting from this agrarian transition. We focus on LSLAs by comparing two scenarios of low-input and high-input agricultural practices, exemplifying systems of production in place before and after the agrarian transition. A shift to high-input crop production requires industrial fertilizer application, mechanization of farming practices and irrigation, which increases by ~5 times fossil-fuel-based energy consumption compared to low-input agriculture. Given the high energy and carbon footprints of LSLAs and concerns over local energy access, our analysis highlights the need for an approach that prioritizes local resource access and incorporates energy-intensity analyses in land use governance.

Canada is committed to reducing its greenhouse gas emissions to 6% below 1990 amounts between 2008 and 2012, and methane is one of several greenhouse gases being targeted for reduction. Methane production from ruminants is one area in which the agriculture sector can contribute to reducing our global impact. Through mathematical modeling, we can further our understanding of factors that control methane production, improve national or global greenhouse gas inventories, and investigate mitigation strategies to reduce overall emissions. The purpose of this study was to compile an extensive database of methane production values measured on beef cattle, and to generate linear and nonlinear equations to predict methane production from variables that describe the diet. Extant methane prediction equations were also evaluated. The linear equation developed with the smallest root mean square prediction error (RMSPE, % observed mean) and residual variance (RV) was Eq. I: CH(4), MJ/d=2.72 (+/-0.543) + [0.0937 (+/-0.0117) x ME intake, MJ/d] + [4.31 (+/-0.215) x Cellulose, kg/d] - [6.49 (+/-0.800) x Hemicellulose, kg/d] - [7.44 (+/-0.521) x Fat, kg/d] [RMSPE=26.9%, with 94% of mean square prediction error (MSPE) being random error; RV=1.13]. Equations based on ratios of one diet variable to another were also generated, and Eq. P, CH(4), MJ/d=2.50 (+/-0.649) - [0.367 (+/-0.0191) x (Starch:ADF)] + [0.766 (+/-0.116) x DMI, kg/d], resulted in the smallest RMSPE values among these equations (RMSPE=28.6%, with 93.6% of MSPE from random error; RV=1.35). Among the nonlinear equations developed, Eq. W, CH(4), MJ/d=10.8 (+/-1.45) x (1-e([-0.141 (+/-0.0381) x DMI, kg/d])), performed well (RMSPE=29.0%, with 93.6% of MSPE from random error; RV=3.06), as did Eq. W(3), CH(4), MJ/d=10.8 (+/-1.45) x [1-e({-[-0.034 x (NFC/NDF)+0.228] x DMI, kg/d})] (RMSPE=28.0%, with 95% of MSPE from random error). Extant equations from a previous publication by the authors performed comparably with, if not better than in some cases, the newly developed equations. Equation selection by users should be based on RV and RMSPE analysis, input variables available to the user, and the diet fed, because the equation selected must account for divergence from a "normal" diet (e.g., high-concentrate diets, high-fat diets).

Earth’s biodiversity and human societies face pollution, overconsumption of natural resources, urbanization, demographic shifts, social and economic inequalities, and habitat loss, many of which are exacerbated by climate change. Here, we review links among climate, biodiversity, and society and develop a roadmap toward sustainability. These include limiting warming to 1.5°C and effectively conserving and restoring functional ecosystems on 30 to 50% of land, freshwater, and ocean “scapes.” We envision a mosaic of interconnected protected and shared spaces, including intensively used spaces, to strengthen self-sustaining biodiversity, the capacity of people and nature to adapt to and mitigate climate change, and nature’s contributions to people. Fostering interlinked human, ecosystem, and planetary health for a livable future urgently requires bold implementation of transformative policy interventions through interconnected institutions, governance, and social systems from local to global levels.