335 research outputs found
Temperature-Dependent Reproductive Success of Stickleback Lateral Plate Morphs: Implications for Population Polymorphism and Range Shifts Under Ocean Warming
Changing environments associated with rapid climate change can shape direct measures of fitness such as reproductive success by altering mating behavior, fecundity and offspring development. Using a polymorphic oceanic population of threespine stickleback (Gasterosteus aculeatus), we investigated whether a 4°C increase in sea surface temperature influenced clutch siring success, reproductive output, and offspring growth among lateral plate morphs. Since low plated morphs are thought to have a selective advantage in warmer environments, we predicted that low plated males should have higher clutch siring success in +4°C environments, and that thermal plasticity of traits (e.g., egg size, offspring growth) should reflect different trait optima in different environments among plate morphs. Parentage analysis of egg clutches revealed temperature-specific clutch siring success, in that low plated males sired more clutches in +4°C environments and completely plated males sired more clutches at ambient (seasonal) temperature. Both completely and low plated females laid larger eggs when acclimated to +4°C, but only completely plated females had smaller clutches at +4°C. Offspring of low and partially plated females grew much less at +4°C compared to those of completely plated females. Taken together, our results demonstrate that ocean warming could impact reproductive success at various levels, with differential effects depending on phenotype, in this case, lateral plate morph. Some traits (clutch siring success, egg size) showed better performance for low plated fish at +4°C, whereas others (e.g., growth) did not. Higher clutch siring success of low plated males at elevated temperature might indicate a future shift in plate morph composition for polymorphic stickleback populations, with potential implications for colonization ability during range shifts under climate change
Synthesis 2006
The purpose of this report is to summarize and synthesize activities and achievements of
the CPWF through the end of 2006.
The CPWF is a CGIAR Challenge Program designed to take on the global challenge of
water scarcity and food security. It takes the form of an international, multi-institutional
research-for-development initiative that brings together scientists, development
specialists, and river basin communities in Africa, Asia and Latin America. It seeks to
create and disseminate international public goods (IPGs) helpful in achieving food
security, reducing poverty, improving livelihoods, reducing agricultureârelated pollution,
and enhancing environmental security.
This Challenge Program is a three-phase, 15-year endeavor. Several years have passed
since the start of Phase 1 (2003-2008) which began with an inception phase in 2003 and
was followed by full CPWF launch in January 2004. Research projects began field
operations in mid-2004. This synthesis report, then, only describes work carried out in
the first two and a half years of the Program.
During this time, CPWF has conducted its research on water and food in nine
benchmark basins, organized around five different themes. This work is being
implemented through âfirst call projectsâ, âbasin focal projectsâ, âsmall grant projectsâ
and âsynthesis researchâ. This present report is one example of the latter.
CPWF projects have made considerable progress in developing innovative technologies,
policies and institutions to address water and food issues. Some projects focused on
improving agricultural water productivity. Others focused on developing mechanisms to
inform multi-stakeholder dialogue and negotiation, or explored ways to value water used
to produce ecosystem services. Advances were also made in understanding water-foodpoverty
links, and their regional and global policy context
Institutions for Agricultural Mitigation: Potential and Challenges in Four Countries
The agriculture sector has great potential to contribute to the mitigation of greenhouse gas emissions through changes in agricultural management and land use. However, the technical potential for agricultural mitigation has yet to translate into actual emission reductions due to considerable constraints to the generation of emission offsets through agricultural projects. These constraints include national and subnational policies and institutional structures as well as institutional and resource constraints at the local level, such as lack of knowledge, organizational capacity, and start-up finance. This paper explores the institutional barriers to agricultural mitigation in four developing countries: Ghana, Morocco, Mozambique, and Vietnam. The findings show that the institutional environment greatly influences the capacity to engage in agricultural mitigation activities. In particular, the centrally planned system in Vietnam provides little space for local, community-based organizations to act collectively around issues of mutual interest, making it difficult to engage numerous smallholders in agricultural mitigation projects. At the same time, government-led mitigation projects may be more feasible in Vietnam compared to the African case studies, where the governments lack well-defined and coordinated strategies and regulations to support mitigation. Governance of contractual obligations is also a challenge to agricultural mitigation. While several organizations in the case study countries have relevant experience for organizing smallholder farmers, most of these organizations lack technical expertise in carbon markets, have limited knowledge of strategies for agricultural mitigation, and lack resources needed for start-up and implementation of mitigation projects
Climate and southern Africa's water-energy-food nexus
In southern Africa, the connections between climate and the water-energy-food nexus are strong. Physical and socioeconomic exposure to climate is high in many areas and in crucial economic sectors. Spatial interdependence is also high, driven for example, by the regional extent of many climate anomalies and river basins and aquifers that span national boundaries. There is now strong evidence of the effects of individual climate anomalies, but associations between national rainfall and Gross Domestic Product and crop production remain relatively weak. The majority of climate models project decreases in annual precipitation for southern Africa, typically by as much as 20% by the 2080s. Impact models suggest these changes would propagate into reduced water availability and crop yields. Recognition of spatial and sectoral interdependencies should inform policies, institutions and investments for enhancing water, energy and food security. Three key political and economic instruments could be strengthened for this purpose; the Southern African Development Community, the Southern African Power Pool, and trade of agricultural products amounting to significant transfers of embedded water
Responding to global challenges in food, energy, environment and water: Risks and options assessment for decision-Making
We analyse the threats of global environmental change, as they relate to food security. First, we review three discourses: (i) âsustainable intensificationâ, or the increase of food supplies without compromising food producing inputs, such as soils and water; (ii) the ânexusâ that seeks to understand links across food, energy, environment and water systems; and (iii) âresilience thinkingâ that focuses on how to ensure the critical capacities of food, energy and water systems are maintained in the presence of uncertainties and threats. Second, we build on these discourses to present the causal, risks and options assessment for decision-making process to improve decision-making in the presence of risks. The process provides a structured, but flexible, approach that moves from problem diagnosis to better risk-based decision-making and outcomes by responding to causal risks within and across food, energy, environment and water systems
Market analysis for cultured proteins in low- and lower-middle income countries.
The global burden of malnutrition is unacceptably high.10 Worldwide, an estimated 22% of children under the age of five were stunted and 8% were wasted in 2018.11 Low-quality diets lacking in essential vitamins, minerals, proteins, and other nutrients are a key contributor to this burden.12 Animal-source foodsâsuch as meat, poultry, fish, eggs, and dairyâare important components of a diverse diet and provide high-quality proteins and other essential nutrients that promote optimal growth and development.13,14,15,16,17As populations and incomes grow, the global demand for animal-source foods is projected to increase substantially, particularly in many low- and lower-middle income countries (LMICs).18,19 However, cost is currently a significant barrier to animal-source food consumption. In addition, meeting this growing demand for animal-source foods will require rapid increases in livestock production, which has significant environmental impacts, requiring considerable land, water, chemical, and energy inputs.10,17,18 Global food production is responsible for roughly one-quarter of all greenhouse gas emissions, most of which (up to 80%) are related to livestock.20,21 Livestock production is also a contributor to water pollution, deforestation, land degradation, overfishing, and antimicrobial resistance.20,22,23 Given these challenges, this report aims to assess the market for potentially more sustainable alternative proteins and their potential for use in LMIC settings. The report focuses on proteins derived from fermentation-based cellular agriculture, called cultured proteins, given their potential near-term time to market and their potential impact in LMIC populations. Most cultured protein manufacturers are developing proteins that are present in animal-source milk and eggs
Giant capsids from lattice self-assembly of cyclodextrin complexes
Proteins can readily assemble into rigid, crystalline and functional structures such as viral capsids and bacterial compartments. Despite ongoing advances, it is still a fundamental challenge to design and synthesize protein-mimetic molecules to form crystalline structures. Here we report the lattice self-assembly of cyclodextrin complexes into a variety of capsidlike structures such as lamellae, helical tubes and hollow rhombic dodecahedra. The dodecahedral morphology has not hitherto been observed in self-assembly systems. The tubes can spontaneously encapsulate colloidal particles and liposomes. The dodecahedra and tubes are respectively comparable to and much larger than the largest known virus. In particular, the resemblance to protein assemblies is not limited to morphology but extends to structural rigidity and crystallinity-a well-defined, 2D rhombic lattice of molecular arrangement is strikingly universal for all the observed structures. We propose a simple design rule for the current lattice self-assembly, potentially opening doors for new protein-mimetic materials
Challenges and Prospects in Ocean Circulation Models
We revisit the challenges and prospects for ocean circulation models following Griffies et al. (2010). Over the past decade, ocean circulation models evolved through improved understanding, numerics, spatial discretization, grid configurations, parameterizations, data assimilation, environmental monitoring, and process-level observations and modeling. Important large scale applications over the last decade are simulations of the Southern Ocean, the Meridional Overturning Circulation and its variability, and regional sea level change. Submesoscale variability is now routinely resolved in process models and permitted in a few global models, and submesoscale effects are parameterized in most global models. The scales where nonhydrostatic effects become important are beginning to be resolved in regional and process models. Coupling to sea ice, ice shelves, and high-resolution atmospheric models has stimulated new ideas and driven improvements in numerics. Observations have provided insight into turbulence and mixing around the globe and its consequences are assessed through perturbed physics models. Relatedly, parameterizations of the mixing and overturning processes in boundary layers and the ocean interior have improved. New diagnostics being used for evaluating models alongside present and novel observations are briefly referenced. The overall goal is summarizing new developments in ocean modeling, including: how new and existing observations can be used, what modeling challenges remain, and how simulations can be used to support observations.Peer reviewe
Efficient land water management practice and cropping system for increasing water and crop productivity in semiâarid tropics
In Indian semi-arid tropics (SATs), low water and crop productivity in Vertisols
and associated soils are mainly due to poor land management and erratic and low
rainfall occurrence. This study was conducted from 2014 to 2016 at the ICRISAT
in India to test the effect of broad bed furrows (BBF) as land water management
against conventional flatbed planting for improving soil water content (SWC) and
water and crop productivity of three cropping systems: sorghum [Sorghum bicolor
(L.) Moench]âchickpea (Cicer arientinum L.) and maize (Zea mays)âgroundnut
(Arachis hypogaea L.) as sequential and pearl millet [Pennisetum glaucum (L.)]
+ pigeonpea [Cajanus cajan (L.) Millsp.] as intercropping, grown under different
nutrients management involving macronutrients (N, P, and K) only and combined
application of macro- and micronutrients. The results stated that the SWC in BBF
was higher over flatbed by 9.35â10.44% in 0- to 0.3-m, 4.56â9.30% in 0.3- to 0.6-m
and 3.85â5.26% in 0.6- to 1.05-m soil depths during the cropping season. Moreover,
depletion of the soil water through plant uptake was higher in BBF than in flatbed.
Among the cropping systems, sorghumâchickpea was the best in bringing highest
system equivalent yield and water productivity with the combined application of
macro- and micronutrients. The BBF minimized water stress at critical crop growth
stages leading to increase crop yield and water productivity in SATs. Thus, BBF
along with the application of macro- and micronutrients could be an adaptation
strategy to mitigate erratic rainfall due to climate change in SATs
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