57 research outputs found

    Accounting for mitigation of N-fertiliser emissions at national and project scales

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    This report provides an overview of the United Nations Framework Convention on Climate Change (UNFCCC) reporting process for national greenhouse gas (GHG) inventories with particular focus on the methodology used for estimating direct nitrous oxide (N2O) emissions from mineral fertiliser. Examples are given of several schemes for sub-national or project- level approaches to monitor and estimate the impact of fertiliser best management practice (BMP) on direct N2O emission reductions. The extent to which these approaches align with those of the national inventory is evaluated and conclusions drawn on actions needed to close any gaps. Collectively, 63% of world fertiliser consumed is reported at the higher Tier 2 and Tier 3 levels. However, countries reporting at the Tier 1 level for direct N2O emissions from fertilisers still predominate, accounting for 180 of the total 191 reporting countries. Case studies of fertiliser BMP were generally found to align well with national inventory methods, mainly through the use of modifiers to Tier 1 & 2 emission factors (EFs). Good quality activity data (AD) is a main challenge to full alignment of project and national inventory-based estimates of fertiliser-induced emissions and emission reductions. Lack of quality AD also limits the extent to which national inventories can capture mitigation impacts. Given the early stage of developing accounting processes for agricultural GHGs, an opportunity now exists to design national GHG inventory processes to reflect emissions savings achieved through mitigation actions such as implementing fertiliser BMPs. To achieve this, it is necessary to strengthen the alignment among different policy instruments, inventory compilation processes and national data providers. In this respect, we should seize opportunities made available from instruments such as the Nationally Determined Contributions that would support development of project-specific, nationally consistent and inventory-aligned measurement, reporting and verification (MRV) methods for capturing mitigation actions, including the establishment of robust baseline AD

    Stress tolerant varieties to counter climate change.

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    gender and inorganic nitrogen what are the implications of moving towards a more balanced use of nitrogen fertilizer in the tropics

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    ABSTRACTFor agriculture to play a role in climate change mitigation strategies to reduce emissions from inorganic nitrogen (N) fertilizer through a more balanced and efficient use are necessary. Such strategies should align with the overarching principle of sustainable intensification and will need to consider the economic, environmental and social trade-offs of reduced fertilizer-related emissions. However, the gender equity dimensions of such strategies are rarely considered. The case studies cited in this paper, from India, Lake Victoria in East Africa and more broadly from sub-Saharan Africa (SSA), show that the negative externalities of imbalanced inorganic N use in high- and low-use scenarios impact more strongly on women and children. We examine, through a literature review of recent work in SSA, the relative jointness of intra-household bargaining processes in low N use scenarios to assess the degree to which they impact upon N use. We suggest that gender-equitable strategies for achieving more ba..

    Climate change impacts and potential benefits of heat-tolerant maize in South Asia

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    Article Purchased; Published online: 14 September 2016Maize is grown by millions of smallholder farmers in South Asia (SA) under diverse environments. The crop is grown in different seasons in a year with varying exposure to weather extremes, including high temperatures at critical growth stages which are expected to increase with climate change. This study assesses the impact of current and future heat stress on maize and the benefit of heat-tolerant varieties in SA. Annual mean maximum temperatures may increase by 1.4–1.8 °C in 2030 and 2.1–2.6 °C in 2050, with large monthly, seasonal, and spatial variations across SA. The extent of heat stressed areas in SA could increase by up to 12 % in 2030 and 21 % in 2050 relative to the baseline. The impact of heat stress and the benefit from heat-tolerant varieties vary with the level of temperature increase and planting season. At a regional scale, climate change would reduce rainfed maize yield by an average of 3.3–6.4 % in 2030 and 5.2–12.2 % in 2050 and irrigated yield by 3–8 % in 2030 and 5–14 % in 2050 if current varieties were grown under the future climate. Under projected climate, heat-tolerant varieties could minimize yield loss (relative to current maize varieties) by up to 36 and 93 % in 2030 and 33 and 86 % in 2050 under rainfed and irrigated conditions, respectively. Heat-tolerant maize varieties, therefore, have the potential to shield maize farmers from severe yield loss due to heat stress and help them adapt to climate change impacts

    Re-assessing Nitrous Oxide Emissions from Croplands Across Mainland China

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    Reliable quantification of nitrous oxide emission is a key to assessing efficiency of use and environmental impacts of N fertilizers in crop production. In this study, N2O emission and yield were quantified with a database of 853 field measurements in 104 reported studies and a regression model was fitted to the associated environmental attributes and management practices from China’s croplands. The fitted emission model explained 48% of the variance in N2O emissions as a function of fertilizer rate, crop type, temperature, soil clay content, and the interaction between N rate and fertilizer type. With all other variables fixed, N2O emissions were lower with rice than with legumes and then other upland crops, lower with organic fertilizers than with mineral fertilizers. We used the subset of the dataset for rice - covering a full range of different typical water regimes, and estimated emissions from China’s rice cultivation to be 31.1 Gg N2O-N per year. The fitted yield model explained 35% of the variance in crop yield as a function of fertilizer rate, temperature, crop type, and soil clay content. Finally, the empirical models for N2O emission and crop yield were coupled to explore the optimum N rates (N rate with minimum N2O emission per unit yield) for combinations of crop and fertilizer types. Consequently, the optimum N application rate ranged between 100 kg N ha−1 and 190 kg N ha−1 respectively with organic and mineral fertilizers, and different crop types. This study therefore improved on existing empirical methods to estimate N2O emissions from China’s croplands and suggests how N rate may be optimized for different crops, fertilizers and site conditions

    Ringed, Bearded, and Ribbon Seal Vocalizations North of Barrow, Alaska: Seasonal Presence and Relationship with Sea Ice

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    The acoustic repertoires of ringed, bearded, and ribbon seals are described, along with their seasonal occurrence and relationship to sea ice concentration. Acoustic recordings were made between September and June over three years (2006 – 09) along the continental slope break in the Chukchi Sea, 120 km north-northwest of Barrow, Alaska. Vocalizations of ringed and bearded seals occurred in winter and during periods of 80% – 100% ice cover but were mostly absent during open water periods. The presence of ringed and bearded seal calls throughout winter and spring suggests that some portion of their population is overwintering. Analysis of the repertoire of ringed and bearded seal calls shows seasonal variation. Ringed seal calls are primarily barks in winter and yelps in spring, while bearded seal moans increase during spring. Ribbon seal calls were detected only in the fall of 2008 during the open water period. The repertoire of known ribbon seal vocalizations was expanded to include three additional calls, and two stereotyped call sequences were common. Retrospective analyses of ringed seal recordings from 1982 and ribbon seal recordings from 1967 showed a high degree of stability in call repertoire across large spatial and temporal scales.Le rĂ©pertoire acoustique des phoques annelĂ©s, des phoques barbus et des phoques Ă  bandes sont dĂ©crits, de mĂȘme que leur prĂ©sence saisonniĂšre et leur rapport avec la concentration de glace de mer. Des enregistrements acoustiques ont Ă©tĂ© effectuĂ©s entre septembre et juin sur une pĂ©riode de trois ans (2006 – 2009), le long de la rupture de la pente continentale, dans la mer des Tchouktches, Ă  120 km au nord-nord-ouest de Barrow, en Alaska. Les vocalisations de phoques annelĂ©s et de phoques barbus Ă©taient prĂ©sentes pendant l’hiver et pendant les pĂ©riodes oĂč la concentration de glace Ă©tait de 80 % Ă  100 %, mais elles se faisaient rares pendant les pĂ©riodes d’eau libre. La prĂ©sence des cris de phoques annelĂ©s et de phoques barbus tout au long de l’hiver et du printemps suggĂšre qu’une partie de leur population hiverne. L’analyse du rĂ©pertoire de cris de phoques annelĂ©s et de phoques barbus indique une variation saisonniĂšre. L’hiver, le cri du phoque annelĂ© prend principalement la forme d’aboiements, tandis que le printemps, il prend la forme de glapissements. Les gĂ©missements du phoque barbu s’intensifient au printemps. Le cri des phoques Ă  bandes n’a Ă©tĂ© captĂ© qu’à l’automne 2008, pendant la pĂ©riode des eaux libres. Le rĂ©pertoire des vocalisations connues du phoque Ă  bandes a Ă©tĂ© Ă©largi pour inclure trois autres cris, bien que deux sĂ©quences de cris stĂ©rĂ©otypĂ©es Ă©taient courantes. L’analyse rĂ©trospective des enregistrements de cris de phoques annelĂ©s de 1982 et de phoques Ă  bandes de 1967 a laissĂ© entrevoir une grande stabilitĂ© du point de vue du rĂ©pertoire des cris, et ce, sur de vastes Ă©chelles spatiales et temporelles

    Cost-effective opportunities for climate change mitigation in Indian agriculture

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    This work was jointly carried out by International Maize and Wheat Improvement Center (CIMMYT) and University of Aberdeen and funded by the CGIAR research program on Climate Change, Agriculture and Food Security (CCAFS). CCAFS’ work is supported by CGIAR Fund Donors and through bilateral funding agreements. For details please visit https://ccafs.cgiar.org/donors. The views expressed in this paper cannot be taken to reflect the official opinions of these organizations. We sincerely acknowledge the input and support provided by various stakeholders in India during stakeholder meetings. We are thankful to Gokul Prasad for graphics assistance.Peer reviewedPublisher PD

    Climate Services for Resilient Development in South Asia and Bangladesh: Semi-Annual and Inception Period Report April 2017

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    Developing countries are at considerable risk from climate variability and climate change, both of which threaten poverty reduction and development efforts. The Climate Services for Resilient Development (CSRD) partnership is led by the United States Government has developed a consortium of global leaders in science, technology and development finance to assist at-risk nations to adapt to these problems. CSRD is aligned with the the Global Framework for Climate Services and works in Bangladesh, Ethiopia, and Colombia to creating and provide timely and useful climate data, information, tools, and services. Within South Asia, efforts to develop agricultural climate services under CSRD are led by the International Maize and Wheat Improvement Center (CIMMYT). CSRD in turn works to support Investment Options Paper (IOP) for Climate Services for Resilient Development in Bangladesh, compiled by the Asian Development Bank (ADB) in 2016. CSRD’s core objectives are to prepare farmers, extension services, and agricultural policy makers with actionable climate information and crop management advisories to reduce agricultural production risks and to increase the resilience of smallholder farming communities. This report summarizes CSRD activities, achievements, and challenges during the project’s inception phase (from the end of November 2017 through April of 2017)

    Measurement of the W+W-gamma Cross Section and Direct Limits on Anomalous Quartic Gauge Boson Couplings at LEP

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    The process e+e- -> W+W-gamma is analysed using the data collected with the L3 detector at LEP at a centre-of-mass energy of 188.6GeV, corresponding to an integrated luminosity of 176.8pb^-1. Based on a sample of 42 selected W+W- candidates containing an isolated hard photon, the W+W-gamma cross section, defined within phase-space cuts, is measured to be: sigma_WWgamma = 290 +/- 80 +/- 16 fb, consistent with the Standard Model expectation. Including the process e+e- -> nu nu gamma gamma, limits are derived on anomalous contributions to the Standard Model quartic vertices W+W- gamma gamma and W+W-Z gamma at 95% CL: -0.043 GeV^-2 < a_0/Lambda^2 < 0.043 GeV^-2 0.08 GeV^-2 < a_c/Lambda^2 < 0.13 GeV^-2 0.41 GeV^-2 < a_n/Lambda^2 < 0.37 GeV^-2
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