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The role of soil organic carbon (SOC) sequestration as a 'win‐win' solution to both climate change and food insecurity receives an increasing promotion. The opportunity may be too good to be missed! Yet the tremendous complexity of the two issues at stake calls for a detailed and nuanced examination of any potential solution, no matter how appealing. Here, we critically re‐examine the benefits of global SOC sequestration strategies on both climate change mitigation and food production. While estimated contributions of SOC sequestration to climate change vary, almost none take SOC saturation into account. Here, we show that including saturation in estimations decreases any potential contribution of SOC sequestration to climate change mitigation by 53%–81% towards 2100. In addition, reviewing more than 21 meta‐analyses, we found that observed yield effects of increasing SOC are inconsistent, ranging from negative to neutral to positive. We find that the promise of a win‐win outcome is confirmed only when specific land management practices are applied under specific conditions. Therefore, we argue that the existing knowledge base does not justify the current trend to set global agendas focusing first and foremost on SOC sequestration. Away from climate‐smart soils, we need a shift towards soil‐smart agriculture, adaptative and adapted to each local context, and where multiple soil functions are quantified concurrently. Only such comprehensive assessments will allow synergies for land sustainability to be maximised and agronomic requirements for food security to be fulfilled. This implies moving away from global targets for SOC in agricultural soils. SOC sequestration may occur along this pathway and contribute to climate change mitigation and should be regarded as a co‐benefit. [ABSTRACT FROM AUTHOR]

More than 100 countries have communicated or adopted new Nationally Determined Contributions (NDCs) and net‐zero target pledges. We investigate the impact on global, national, sectoral, and individual greenhouse gas emissions projections under different scenarios based on the announced NDCs and net‐zero pledges using the IMAGE integrated assessment model. Our results show that while the net‐zero pledges, if implemented, could be an important step forward, they are still not enough to achieve the Paris Agreement goals of well below 2°C and preferably 1.5°C by the end of the century. Still, our net‐zero scenarios project significant all‐sector decarbonization, in particular, electricity; however, certain sectors like industry and transport prove hard to completely abate. [ABSTRACT FROM AUTHOR]

Large‐scale bioenergy plays a key role in climate change mitigation scenarios, but its efficacy is uncertain. This study aims to quantify that uncertainty by contrasting the results of three different types of models under the same mitigation scenario (RCP2.6‐SSP2), consistent with a 2°C temperature target. This analysis focuses on a single bioenergy feedstock, Miscanthus × giganteus, and contrasts projections for its yields and environmental effects from an integrated assessment model (IMAGE), a land surface and dynamic global vegetation model tailored to Miscanthus bioenergy (JULES) and a bioenergy crop model (MiscanFor). Under the present climate, JULES, IMAGE and MiscanFor capture the observed magnitude and variability in Miscanthus yields across Europe; yet in the tropics JULES and IMAGE predict high yields, whereas MiscanFor predicts widespread drought‐related diebacks. 2040–2049 projections show there is a rapid scale up of over 200 Mha bioenergy cropping area in the tropics. Resulting biomass yield ranges from 12 (MiscanFor) to 39 (JULES) Gt dry matter over that decade. Change in soil carbon ranges from +0.7 Pg C (MiscanFor) to −2.8 Pg C (JULES), depending on preceding land cover and soil carbon.2090–99 projections show large‐scale biomass energy with carbon capture and storage (BECCS) is projected in Europe. The models agree that <2°C global warming will increase yields in the higher latitudes, but drought stress in the Mediterranean region could produce low yields (MiscanFor), and significant losses of soil carbon (JULES and IMAGE). These results highlight the uncertainty in rapidly scaling‐up biomass energy supply, especially in dry tropical climates and in regions where future climate change could result in drier conditions. This has important policy implications—because prominently used scenarios to limit warming to 'well below 2°C' (including the one explored here) depend upon its effectiveness. [ABSTRACT FROM AUTHOR]

Modern sustainable bioenergy can contribute toward mid‐century European energy decarbonization targets by replacing fossil fuels. Fulfilling this role would require access to increased volumes of bioenergy, with extra‐EU imports projected to play an important part. Access to this resource on the international marketplace is not governed by Europe's economic competitiveness alone. This study investigates geopolitical, socioeconomic, and regulatory considerations that can influence Europe's bioenergy imports but that are so far underexplored. The effect of these constraints on European import volumes, sourcing regions, mitigation potential, and their implications for European and global emissions is projected to the year 2050 using a global integrated assessment model. The projections show that Europe can significantly increase imports from 1.5 EJ year−1 in 2020 to 8.1 EJ year−1 by 2050 whilst remaining compliant with Renewables Energy Directive recast II (RED II) greenhouse gas (GHG) criteria. Under these conditions, bioenergy could provide annual GHG mitigation of 0.44 GtCO2eq. in 2050. However, achieving this would require a structural diversification of trading partners from the present. Furthermore, socioeconomic and logistical concerns may limit the feasibility of some of the projected major sourcing regions, including Africa and South America. Failure to overcome these challenges within supplying regions could limit European imports by 60%, reducing annual mitigation to 0.16 GtCO2eq. in 2050. From a global perspective, regions with a comparatively carbon‐intense energy system offer an alternative destination for globally traded biomass that could increase the mitigative potential of bioenergy. © 2022 The Authors. Biofuels, Bioproducts and Biorefining published by Society of Industrial Chemistry and John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Bioenergy with carbon capture and storage (BECCS) based on purpose‐grown lignocellulosic crops can provide negative CO2 emissions to mitigate climate change, but its land requirements present a threat to biodiversity. Here, we analyse the implications of crop‐based BECCS for global terrestrial vertebrate species richness, considering both the land‐use change (LUC) required for BECCS and the climate change prevented by BECCS. LUC impacts are determined using global‐equivalent, species–area relationship‐based loss factors. We find that sequestering 0.5–5 Gtonne of CO2 per year with lignocellulosic crop‐based BECCS would require hundreds of Mha of land, and commit tens of terrestrial vertebrate species to extinction. Species loss per unit of negative emissions decreases with: (i) longer lifetimes of BECCS systems, (ii) less overall deployment of crop‐based BECCS and (iii) optimal land allocation, that is prioritizing locations with the lowest species loss per negative emission potential, rather than minimizing overall land use or prioritizing locations with the lowest biodiversity. The consequences of prevented climate change for biodiversity are based on existing climate response relationships. Our tentative comparison shows that for crop‐based BECCS considered over 30 years, LUC impacts on vertebrate species richness may outweigh the positive effects of prevented climate change. Conversely, for BECCS considered over 80 years, the positive effects of climate change mitigation on biodiversity may outweigh the negative effects of LUC. However, both effects and their interaction are highly uncertain and require further understanding, along with the analysis of additional species groups and biodiversity metrics. We conclude that factoring in biodiversity means lignocellulosic crop‐based BECCS should be used early to achieve the required mitigation over longer time periods, on optimal biomass cultivation locations, and most importantly, as little as possible where conversion of natural land is involved, looking instead to sustainably grown or residual biomass‐based feedstocks and alternative strategies for carbon dioxide removal. [ABSTRACT FROM AUTHOR]

Scenario‐based biodiversity modelling is a powerful approach to evaluate how possible future socio‐economic developments may affect biodiversity. Here, we evaluated the changes in terrestrial biodiversity intactness, expressed by the mean species abundance (MSA) metric, resulting from three of the shared socio‐economic pathways (SSPs) combined with different levels of climate change (according to representative concentration pathways [RCPs]): a future oriented towards sustainability (SSP1xRCP2.6), a future determined by a politically divided world (SSP3xRCP6.0) and a future with continued global dependency on fossil fuels (SSP5xRCP8.5). To this end, we first updated the GLOBIO model, which now runs at a spatial resolution of 10 arc‐seconds (~300 m), contains new modules for downscaling land use and for quantifying impacts of hunting in the tropics, and updated modules to quantify impacts of climate change, land use, habitat fragmentation and nitrogen pollution. We then used the updated model to project terrestrial biodiversity intactness from 2015 to 2050 as a function of land use and climate changes corresponding with the selected scenarios. We estimated a global area‐weighted mean MSA of 0.56 for 2015. Biodiversity intactness declined in all three scenarios, yet the decline was smaller in the sustainability scenario (−0.02) than the regional rivalry and fossil‐fuelled development scenarios (−0.06 and −0.05 respectively). We further found considerable variation in projected biodiversity change among different world regions, with large future losses particularly for sub‐Saharan Africa. In some scenario‐region combinations, we projected future biodiversity recovery due to reduced demands for agricultural land, yet this recovery was counteracted by increased impacts of other pressures (notably climate change and road disturbance). Effective measures to halt or reverse the decline of terrestrial biodiversity should not only reduce land demand (e.g. by increasing agricultural productivity and dietary changes) but also focus on reducing or mitigating the impacts of other pressures. [ABSTRACT FROM AUTHOR]

Abstract: The impacts of land use have been shown to have considerable influence on regional climate. With the recent international commitment to limit global warming to well below 2°C, emission reductions need to be ambitious and could involve major land‐use change (LUC). Land‐based mitigation efforts to curb emissions growth include increasing terrestrial carbon sequestration through reforestation, or the adoption of bioenergy crops. These activities influence local climate through biogeophysical feedbacks, however, it is uncertain how important they are for a 1.5° climate target. This was the motivation for HAPPI‐Land: the half a degree additional warming, prognosis, and projected impacts—land‐use scenario experiment. Using four Earth system models, we present the first multimodel results from HAPPI‐Land and demonstrate the critical role of land use for understanding the characteristics of regional climate extremes in low‐emission scenarios. In particular, our results show that changes in temperature extremes due to LUC are comparable in magnitude to changes arising from half a degree of global warming. We also demonstrate that LUC contributes to more than 20% of the change in temperature extremes for large land areas concentrated over the Northern Hemisphere. However, we also identify sources of uncertainty that influence the multimodel consensus of our results including how LUC is implemented and the corresponding biogeophysical feedbacks that perturb climate. Therefore, our results highlight the urgent need to resolve the challenges in implementing LUC across models to quantify the impacts and consider how LUC contributes to regional changes in extremes associated with sustainable development pathways. [ABSTRACT FROM AUTHOR]

The article discusses the researches on biogeochemical and biophysical interactions of land-cover change with climate system. It says that Integrated Assessment modeling and Earth System stresses the significance of land use and land cover change to understand its interactions with socio-economic and climate systems. It argues that major researches on land use and land cover change helps in understanding ecosystem and goods services provision, management decisions, and managing climate change.

In this study, we analyze the impact of fertilizer- and manure-induced N2O emissions due to energy crop production on the reduction of greenhouse gas (GHG) emissions when conventional transportation fuels are replaced by first-generation biofuels (also taking account of other GHG emissions during the entire life cycle). We calculate the nitrous oxide (N2O) emissions by applying a statistical model that uses spatial data on climate and soil. For the land use that is assumed to be replaced by energy crop production (the ‘reference land-use system’), we explore a variety of options, the most important of which are cropland for food production, grassland, and natural vegetation. Calculations are also done in the case that emissions due to energy crop production are fully additional and thus no reference is considered. The results are combined with data on other emissions due to biofuels production that are derived from existing studies, resulting in total GHG emission reduction potentials for major biofuels compared with conventional fuels. The results show that N2O emissions can have an important impact on the overall GHG balance of biofuels, though there are large uncertainties. The most important ones are those in the statistical model and the GHG emissions not related to land use. Ethanol produced from sugar cane and sugar beet are relatively robust GHG savers: these biofuels change the GHG emissions by −103% to −60% (sugar cane) and −58% to −17% (sugar beet), compared with conventional transportation fuels and depending on the reference land-use system that is considered. The use of diesel from palm fruit also results in a relatively constant and substantial change of the GHG emissions by −75% to −39%. For corn and wheat ethanol, the figures are −38% to 11% and −107% to 53%, respectively. Rapeseed diesel changes the GHG emissions by −81% to 72% and soybean diesel by −111% to 44%. Optimized crop management, which involves the use of state-of-the-art agricultural technologies combined with an optimized fertilization regime and the use of nitrification inhibitors, can reduce N2O emissions substantially and change the GHG emissions by up to −135 percent points (pp) compared with conventional management. However, the uncertainties in the statistical N2O emission model and in the data on non-land-use GHG emissions due to biofuels production are large; they can change the GHG emission reduction by between −152 and 87 pp. [ABSTRACT FROM AUTHOR]

Aim Over the next 100 years, human-driven climate change and resulting changes in species occurrences will have global impacts on biodiversity, ecosystem function, and human health. Here we examine how climate change may affect the occurrences of tick species in Africa and alter the suitability of habitat outside Africa for African ticks. Location Africa and the world. Methods We predicted continental and global changes in habitat suitability for each of 73 African tick species, using multiple regression models in different climate change scenarios that cover a wide range of uncertainty. Results Global habitat suitability improves for nearly all tick species under each of a representative range of eight climate change scenarios. Depending on the scenario, African tick species experience an average increase in global habitat suitability of between 1 million and 9 million square kilometres between 1990 and 2100. Main conclusions The potential for successful translocations of ticks and their pathogens from Africa to the rest of the world is likely to increase over the next 100 years. Although the general trend is one of range expansion, there are winners and losers among tick species in each scenario, suggesting that tick community composition will be disrupted substantially by climate change. If this is also typical of other invertebrates, then climate change will disrupt not only the geographic location of communities but also their structure. Changes in tick communities are also likely to influence tick-borne pathogens. [ABSTRACT FROM AUTHOR]

Reductions in river discharge (water availability) like those from climate change or increased water withdrawal, reduce freshwater biodiversity. We combined two scenarios from the Intergovernmental Panel for Climate Change with a global hydrological model to build global scenarios of future losses in river discharge from climate change and increased water withdrawal. Applying these results to known relationships between fish species and discharge, we build scenarios of losses (at equilibrium) of riverine fish richness. In rivers with reduced discharge, up to 75% (quartile range 4–22%) of local fish biodiversity would be headed toward extinction by 2070 because of combined changes in climate and water consumption. Fish loss in the scenarios fell disproportionately on poor countries. Reductions in water consumption could prevent many of the extinctions in these scenarios. [ABSTRACT FROM AUTHOR]

A correction to the article "The contribution of N2O to the greenhouse gas balance of first-generation biofuels" that was published in the volume 15, 2010 issue is presented.