43 research outputs found
Restoring Rangelands for Nutrition and Health for Humans and Livestock
Drylands cover 40% of the global land area and host 2 billion people, of which 90% live in low- or middleincome countries. Drylands often face severe land degradation, low agricultural productivity, rapid population growth, widespread poverty, and poor health. Governance structures and institutions are often eroded. Livestock-based livelihoods, largely depending on seasonal migration are common. Pastoralist communities and their land are highly vulnerable to climate shocks, while there are also changes in land tenure, insecurity/conflicts and rapid infrastructure development. Drylands Transform is an interdisciplinary research project revolving around the UN Sustainable Development Goals (SDGs). The project aim is to contribute new knowledge to a transformative change and sustainable development of drylands in East Africa to help escape the ongoing negative spiral of land, livestock and livelihood degradation. We investigate the links between land health, livelihoods, human well-being, and land management and governance with several study sites along the Kenya-Uganda border. Through strong stakeholder engagement we will explore challenges and pathways towards a social-ecological transformation in these drylands. The entry point is the urgent need to identify and enhance synergies between food and nutrition security (SDG2), land and ecosystem health (SDG15) and governance and justice (SDG16) for sustainable dryland development, aiming to improve health and equity (SDGs 3 and 5), while minimizing trade-offs between agricultural productivity, natural resources management and climate change. We are using innovative field research approaches focusing on livelihood improvement through rangeland (grazing areas) restoration and governance interventions. We will present results from the initial work to assess land health using the Land Degradation Surveillance Framework and explore the links with human health and well-being through household survey data. We will also show how we will co-develop sustainable dryland management options (e.g., field experiments with fodder grasses and shrubs) with local communities and set-up knowledge sharing hubs
LegumeSELECT: A baseline characterisation of four selected sites in Kisii and Migori counties of western Kenya
Supporting smallholder farmers' decisions on legume use in East Africa - The LegumeCHOICE approach
Grain legumes and dryland cereals for enhancing carbon sequestration in semi-arid and sub-humid agro-ecologies of Africa and South Asia
Sorghum, millets (pearl and finger millet) and grain legumes (chickpea, common bean, cowpea, lentils, pigeon pea and soybean), collectively referred to as GLDC under the CGIAR research program on Grain Legumes and Dryland Cereals, are commonly grown, eaten and traded by small holder farmers in Africa and South Asia. These crops contribute to food and nutritional security, environmental sustainability, and economic growth in the region. However, their possible contribution to carbon sequestration through biomass production and accumulation of soil organic carbon (SOC) is not known. To find out more about their contribution, and how to increase SOC, this study reviewed the evidence of carbon sequestration in farming systems that integrate GLDC in Africa and South Asia. A total of 437 publications reporting SOC and its proxies across 32 countries in Africa (N=250 studies) and South Asia (N=187) were identified as sources of evidence for carbon sequestration. Among these, 179 publications provided appropriate control groups for evaluating changes in aboveground carbon when GLDC were integrated under intercrop (n=38), crop rotation (n=8) or agroforestry (n=13), or when improved varieties of GLDC were compared with local varieties (n=14). A further 81 publications compared SOC content at the start and the end of the experiment while 43 publications compared SOC between farms growing GLDC and those which did not. Aboveground carbon of GLDC was found to be 1.51±0.05 Mg/ha in Africa and 2.29±0.10 Mg/ha in South Asia. Absolute SOC concentration in the topsoil (0-30 cm) was 0.96±0.06% in Africa and 0.58±0.04 in South Asia. It was observed that GLDC produced more aboveground carbon and significantly increased SOC when grown as intercrops and in crop rotations. The increase, however, depended on the species and whether the crop was a legume or a cereal. The largest amount of aboveground carbon (>2 Mg/ha) was found in cereals (and pigeon pea) while the largest increase in SOC was found in farming systems that included legumes. Aboveground carbon of improved varieties of GLDC was lower compared to local varieties. Soils which had low initial (32%) showed the greatest potential for carbon sequestration when GLDC were grown. Among the GLDC crops, pigeon pea which is a perennial grain legume showed the highest biomass production and carbon sequestration in the soil when integrated into farming systems in Africa and South Asia. Findings from this study underscore the importance of aboveground residues in regulating the addition of carbon to the soil, and the role of legumes in the enhancement of SOC
The N-P-K soil nutrient balance of portuguese cropland in the 1950s: the transition from organic to chemical fertilization
Agricultural nutrient balances have been receiving increasing attention in both historical and
nutrient management research. The main objectives of this study were to further develop balance
methodologies and to carry out a comprehensive assessment of the functioning and nutrient cycling
of 1950s agroecosystems in Portugal. Additionally, the main implications for the history of agriculture
in Portugal were discussed from the standpoint of soil fertility. We used a mass balance approach
that comprises virtually all nitrogen (N), phosphorus (P) and potassium (K) inputs and outputs from
cropland topsoil for average conditions in the period 1951â56. We found a consistent deficit in N, both
for nationwide (â2.1 kg.haâ1.yrâ1) and arable crops (â1.6 kg.haâ1.yrâ1) estimates, that was rectified
in the turn to the 1960 decade. P and K were, in contrast, accumulating in the soil (4.2â4.6 kg.haâ1.yrâ1
and 1.0â3.0 kg.haâ1.yrâ1, respectively). We observed that the 1950s is the very moment of inflection
from an agriculture fertilized predominantly through reused N in biomass (livestock excretions plus
marine, plant and human waste sources) to one where chemical fertilizers prevailed. It is suggested that
N deficiency played an important role in this transitioninfo:eu-repo/semantics/publishedVersio
Nitrogen management in organic farming: comparison of crop rotation residual effects on yields, N leaching and soil conditions
Suprimento de potåssio em função da adubação potåssica residual em um Latossolo Vermelho do Cerrado
Considering Soil Potassium Pools with Dissimilar Plant Availability
Soil potassium (K) has traditionally been portrayed as residing in four functional pools: solution K, exchangeable K, interlayer (sometimes referred to as âfixedâ or ânonexchangeableâ) K, and structural K in primary minerals. However, this four-pool model and associated terminology have created confusion in understanding the dynamics of K supply to plants and the fate of K returned to the soil in fertilizers, residues, or waste products. This chapter presents an alternative framework to depict soil K pools. The framework distinguishes between micas and feldspars as K-bearing primary minerals, based on the presence of K in interlayer positions or three-dimensional framework structures, respectively; identifies a pool of K in neoformed secondary minerals that can include fertilizer reaction products; and replaces the âexchangeableâ K pool with a pool defined as âsurface-adsorbedâ K, identifying where the K is located and the mechanism by which it is held rather than identification based on particular soil testing procedures. In this chapter, we discuss these K pools and their behavior in relation to plant K acquisition and soil K dynamics
Soil classification problems of 13 Nordic Reference Soils
Koko teksti on CD-ROM-levyllÀ, 7 sivuavo
Perspectives on nutrient management in mixed farming systems
Changes in agricultural subsidies in Europe and the ready availability of fertilisers have allowed a spatial decoupling of livestock and crop production. This has increased the flow of nutrients that occurs between farms compared to within individual farms. In terms of nutrient cycling mixed farms provide the opportunity to re-integrate aspects of agricultural production. The degree of integration between crop and livestock production is defined by the reliance on the use of home-produced feed compared to imported feed, and is independent of intensity. Farm scale nutrient use efficiency (NUE) is inversely related to stocking density. Management of inputs and/or internal flows offers the scope to improve NUE on mixed farms. Greatest uncertainties in calculating NUE are associated with variation in yield and composition of home produced feed and consequent manure composition. Three key areas are addressed here 1) the role of livestock diet in manipulating the amount and availability of manure nutrients 2) the impact of manure management on nutrient losses and 3) nutrient management through the integration of crops and livestock in rotations. While not all the associated issues are unique to mixed farming these three areas all influence NUE