Can agriculture reach net zero emissions by 2050?

Significant GHG emissions reductions in agriculture are achievable through reducing emission intensity of production, but population growth and dietary changes may offset absolute emissions reductions. Emission reductions consistent with 2030 targets are achievable in many countries; attaining the 2050 targets will require innovation and systems transformation. Net zero agriculture cannot be achieved without sinks. Governance, economics, and sociocultural factors are the keys to food system transformations

Soil nitrous oxide and methane fluxes from a land-use change transition of primary forest to oil palm in an Indonesian peatland

Despite the documented increase in greenhouse gas (GHG) emissions from Southeast Asian peat swamp forest degradation and conversion to oil palm over recent decades, reliable estimates of emissions of nitrous oxide (N2O) and methane (CH4) are lacking. We measured soil fluxes of N2O and CH4 and their environmental controls along a peatland transition from primary forest (PF) to degraded drained forest (DF) to oil palm plantation (OP) over 18 months in Jambi, Sumatra, Indonesia. Sampling was conducted monthly at all sites and more intensively following two fertilization events in the OP. Mean annual emissions of N2O (kg N ha−1 yr−1) were 1.7 ± 0.2 for the PF, 2.3 ± 0.2 for the DF and for the OP 8.1 ± 0.8 without drainage canals (DC) and 7.7 ± 0.7 including DC. High N2O emissions in the OP were driven by peat decomposition, not by N fertilizer addition. Mean CH4 annual fluxes (kg C ha−1 yr−1) were 8.2 ± 1.9 for the PF, 1.9 ± 0.4 for the DF, and 1.6 ± 0.3 for the OP with DC and 1.1 ± 0.2 without. Considering their 20-year global warming potentials (GWP), the combined non-CO2 GHG emission (Mg CO2-equivalent ha−1 yr−1) was 3.3 ± 0.6 for the PF and 1.6 ± 0.2 for the DF. The emission in the OP (3.8 ± 0.3 with or without DC) was similar to the PF because reductions in CH4 emissions offset N2O increases. However, considering 100-year GWP, the combined non-CO2 GHG emission was larger in the OP (3.4 ± 0.3 with DC and 3.5 ± 0.3 without) compared to both the PF and the DF (1.5 ± 0.2 and 1.2 ± 0.1, respectively). The increase in peat N2O emissions associated with the land-use change transition from primary forest to oil palm plantation at our sites provides further evidence of the urgent need to protect tropical peat swamp forests from drainage and conversion

Modeling the spatial distribution of soil organic carbon and carbon stocks in the Casanare flooded savannas of the Colombian Llanos

Abstract Flooded savannas are valuable and extensive ecosystems in South America, but not widely studied. In this study, we quantify the spatial distribution of soil organic carbon (SOC) content and stocks in the Casanare flooded savannas. We sampled 80 sites at two soil-depth intervals (0-10 and 10-30 cm), where SOC values ranged from 0.41% in the surface and 0.23% in the sub-surface of drier soils to over 14.50% and 7.51%, in soils that experienced seasonal flooding. Spatial predictions of SOC were done through two digital soil mapping (DSM) approaches: Expert-Knowledge (EK) and Random-Forest (RF). Although both approaches performed well, EK was slightly superior at predicting SOC. Covariates derived from vegetation cover, topography, and soil properties were identified as key drivers in controlling its distribution. Total SOC stocks were 55.07 Mt with a mean density of 83.1±24.3 t·ha -1 in the first 30 cm of soil, with 12.3% of this located in areas that experience long periods of flooding (semi-seasonal savannas) , which represented only 7.9% of the study area (664,752 ha). Although the study area represents only 15% of the total area of the Casanare department, the intensive pressure of human development could result in the reduction of its SOC stocks and the release of important amounts of greenhouse gases into the atmosphere. At regional level, the impact of a large-scale land use conversions of the flooded Llanos del Orinoco ecosystem area (15 Mha) could transform this area in a future source of important global emissions if correct decisions are not taken regarding the land management of the region

Will CO2 Emissions from Drained Tropical Peatlands Decline Over Time? Links Between Soil Organic Matter Quality, Nutrients, and C Mineralization Rates

Peer Revie

The Role of Agriculture in the UN Climate Talks

Agriculture, and consequently food security and livelihoods, is already being affected by climate change, according to latest science from the IPCC. The various strands of work already underway on agriculture within the UNFCCC process can be strengthened and made more coherent. A 2015 climate agreement should reference food production and provide the financial, technical and capacity building support for countries to devise ambitious actions for the agricultural sector. A new climate agreement should be consistent with the Sustainable Development Goal (SDG) proces

What is out there? A typology of land restoration projects in Latin America and the Caribbean

Abstract Restoring degraded lands is high on the international agenda and the number of restoration projects in Latin America and the Caribbean (LAC) has increased considerably over the past decades. However, the variety of approaches used have not been systematically documented and analyzed. We aimed to develop a restoration typology as a function of the geographical and socio-economical setting, planning, timeframe, finances, implementation, monitoring and potential impact, which will help to discern broad patterns and identify gaps in project implementation in LAC. We categorized 97 restoration projects using Multiple Correspondence Analysis and a Hierarchical Clustering on Principal Components. Three main restoration types emerged from the clustering, with the main defining variables being: (1) project area under restoration, (2) amount of funding received, (3) source of funding and (4) monitoring efforts. The first type are large-scale projects, which receive high amounts of funding provided by international donors, and with a well-established monitoring plan; the second type are projects financed with private money, typically lacking a sound monitoring program; and the third type represents small projects with low amounts of funding, financed with public funds from national governments, often with a rudimentary monitoring plan. The typology enables a comparative analysis of the status and trends of restoration activities across Latin America. We conclude that, despite growing awareness and recognition that integrated approaches are needed to revert complex and interconnected socio-economic and environmental issues like land degradation, the socio-economic dimension remains underexposed in the majority of restoration projects, whereas monitoring is still regarded as an extra cost instead of a necessary investment

Progress on agriculture in the UN climate talks: How COP21 can ensure a food-secure future

Agriculture, and consequently food security and livelihoods, is already being affected by climate change, according to latest science from the IPCC (Porter et al. 2014). The IPCC agrees that the world needs to produce at least 50% more food than we do today in order to meet the goal of feeding a projected 9 billion people by 2050. This must be achieved in the face of climatic variability and change, growing constraints on water and land for crops and livestock, and declining wild capture fishery stocks. Although the protection of food security lies within the core objective of the United Nations Framework Convention on Climate Change (UNFCCC) (Article 2), formal arrangements for addressing agriculture within COP21 are unlikely. CGIAR would welcome the strengthening of aspirations for food security through action on mitigation and adaptation within a new agreement. We recognise that the new climate agreement is unlikely to be prescriptive about how adaptation in agriculture is supported and how agriculture might contribute to emission cuts. These issues are addressed within countries’ INDCs and determined at national level

Characterizing and evaluating the impacts of national land restoration initiatives on ecosystem services in Ethiopia

Land restoration is considered to be the remedy for 21st century global challenges of land degradation. As a result, various land restoration and conservation efforts are underway at different scales. Ethiopia is one of the countries with huge investments in land restoration. Tremendous land management practices have been implemented across the country since the 1970s. However, the spatial distribution of the interventions has not been documented, and there is no systematic, quantitative evidence on whether land restoration efforts have achieved the restoration of desired ecosystem services. Therefore, we carried out a meta‐analysis of peer‐reviewed scientific literature related to land restoration efforts and their impacts in Ethiopia. Results show that most of the large‐scale projects have been implemented in the highlands, specifically in Tigray and Amhara regions covering about 24 agro‐ecological zones, and land restoration impact studies are mostly focused in the highlands but restricted in about 11 agro‐ecological zones. The highest mean effect on agricultural productivity is obtained from the combination of bunds and biological interventions followed by conservation agriculture practices with 170 % and 18% increases, respectively. However, bunds alone, biological intervention alone, and terracing (Fanya Juu) reveal negative effects on productivity. The mean effect of all land restoration interventions on soil organic carbon is positive, the highest effect being from “bunds + biological” (139%) followed by exclosure (90%). Reduced soil erosion and runoff are the dominant impacts of all interventions. The results can be used to improve existing guidelines to better match land restoration options with specific desired ecosystem functions and services. While the focus of this study was on the evaluation of the impacts of land restoration efforts on selected ecosystem services, impacts on livelihood and national socio‐economy have not been examined. Thus, strengthening socio‐economic studies at national scale to assess the sustainability of land restoration initiatives are an essential next step