1,720,973 research outputs found
A growing produce bubble: United States produce tied to Mexico's unsustainable agricultural water use
Full text linkGlobal analyses have revealed virtual drains and gains of water between trading countries, with Mexico ranking as one of the countries with the fastest increase in unsustainable water consumption in agriculture for export markets, since 2000. It is unclear, however, how Mexico has reshaped its crop production and associated reliance on freshwater resources to satisfy growing domestic and international markets, especially the United States (US). While the Mexico-US partnership has been identified as one supported by unsustainable irrigation water, the spatial understanding of its strain on water resources has remained at the national scale and without context of the crops driving the change. In this analysis, we focus on the evolution of Mexican agriculture since 1994, the year the North American Free Trade Agreement was enacted, to identify hotspots of water unsustainability in crop production in the domestic and US supply chain. Using a global process-based crop water model, we find that between 1994 and 2015, rainwater (or 'green' water) and irrigation (or 'blue') water consumed in the production of crops increased by one fourth nationally, while water in crops exported to the US doubled. Virtual export of blue water embodied in the trade of berries increased five orders of magnitude; a substantial growth in blue water export was also associated with trade to the US of cereals, fruits, nuts, vegetables, pulses, and tubers. Our results show that in Mexico irrigated water plays an increasingly prominent role in export agriculture, and that many healthy crops that dominate US imports from the world are grown in water scarce Mexican municipalities relying on unsustainable irrigation practices. This serves as a warning for the sustainability of future Mexican healthy food supplies, both for the domestic market and for export to the US
The value generated by irrigation in the command areas of new agricultural dams in Africa
No full textRecent years have seen continued investments in new irrigation dams across Africa, which have led to the emergence of new irrigated areas in their vicinity (or ‘command areas’). The ability to irrigate land that was previously only rainfed allows for an increase in crop production and is therefore associated with an increase in the value generated by agriculture. What is the value produced by irrigation in the command areas of new major African dams? Here we use crop water modeling under a variety of crop distribution scenarios to determine the increase in agricultural value induced by irrigation in the ‘command’ areas adjacent to the major irrigation dams. We use these estimates to determine the shadow price of irrigation water in these regions along with the increase in land value and land's economic productivity. We focus on dams built in Africa between 2000 and 2015, which are clustered in northern, east, and southern Africa. This study provides a framework to determine the economic benefits of irrigation dams and evaluate the increase in agricultural revenues resulting from access to water for irrigation
Water resources constraints in achieving silk production self-sufficiency in India
No full textOne of the main challenges for India is increasing food security and promoting economic development using the domestic finite and already stressed natural resources. In the last decades silk production has been booming in India in response to the 2025 silk self-sufficiency goal set by the Indian Ministry of Textile. It is not clear to which extent mulberry (Morus alba), used to feed silkworm in 70% of the total domestic silk production, can be expanded in the wastelands identified by the Indian Government as suitable for moriculture without both endangering natural resources and causing competition for natural resources with the food sector. This issue is here investigated by a) assessing mulberry water consumption (rain and irrigation) in the plantations presently cultivated and in all the wastelands selected by the government for the expansion of moriculture as well; b) analyzing annual and sub-annual water scarcity induced by mulberry plantations within the plantations; c) studying the potential competition for natural resources between food crops and mulberry. To this end the dynamic spatially distributed crop water balance WATNEEDS model has been used to analyze two different scenarios being the reference scenario considering the present climate and land cover, and the “silk expansion scenario” combining present climate and the new mulberry plantations. Results for the reference scenario show mulberry expansion areas already suffering food insecurity and water scarcity in the dry period. Here, the expansion of mulberry cultivation is shown to exacerbate water scarcity in pre-monsoon months especially in the North-Eastern Region affecting on a yearly scale eleven million people. Results also show expanding food production on wastelands rather than mulberry could be a viable solution for alleviating the burden of malnutrition
Socio-environmental impacts of diamond mining areas in the Democratic Republic of Congo
No full textThe mining industry of the Democratic Republic of the Congo (DRC) represents the most important sector of the country's economy, and the DRC belongs to the world top five diamond producers. Artisanal small-scale mining (ASM) of alluvial diamonds represents an important source of alternative income for subsistence farmers, but it also leads to several socio-environmental impacts: deforestation, river pollution, water resources exploitation, unhealthy, unregulated and sometimes dangerous work environments. We perform a data-driven comprehensive analysis of the impact of the diamond mining industry on natural resources and assess the potential relevance of these resources to the DRC food system. To this end, we evaluate land and water resources consumption associated with diamond mining from 2001 to 2018, cross-referencing high-resolution data on mines, land use and tree cover, and using a dynamic and spatially distributed agro-hydrological model. We leverage disaggregated agrological data to provide alternative resources allocation scenarios, and use subnational development indicators and spatially explicit conflict data to frame our analysis within the socio-economic context. We find that, despite the richness in natural resources of the DRC, the impact of diamond mining is relevant because of its effects on ecology, economy, and society. Resources and efforts currently put into the mining industry may have the potential to alleviate the malnourishment crisis in DRC if diverted towards the construction of a more structured and resilient food system. Phenomena such as the illicit trafficking of diamonds and their use to finance wars contribute to nullify the potential of mining as an alternative source of income for subsistence farmers
A Blue Water Scarcity-Based Method for Hydrologically Sustainable Agricultural Expansion Design
No full textSustainable development and intergenerational responsibility entail the prudent use of natural resources. Water availability can constrain agriculture, a key sector in terms of resources consumed and goods and services provided. The sustainability of its intensification and expansion has been studied, often with a particular focus on water. Agricultural strategies have been based on local water availability, and some downstream effects have been evaluated. However, a method to identify and quantify hydrologically sustainable land use and crop use changes directly accounting for downstream effects is yet to be defined. We propose a framework to design land-use and crop-use changes preventing local and downstream effects. We apply it on of coffee plantations expansion in Kenya, a sector that is growing and planned to grow, given its agricultural, economic and social development potential, not without risks associated to hydroclimatic change. We use crop- and land-use specific hydrological modeling to simulate water scarcity impacts of coffee plantation expansion onto available suitable areas, and use the results to iteratively identify and filter out expansion areas increasing water scarcity locally or downstream. This assessment proves effective in preserving water availability, identifying 10% of the suitable and available areas as hydrologically sustainable. Total water footprints are similar in these expansion areas and in currently used areas, but expansion areas have higher precipitation-generated water availability. The proposed methodology locates and quantifies areas in a physically robust way, maintaining flexibility to the selected expansion scenario. Thus, the methodology is replicable for planning hydrologically agricultural development.A new methodology for designing sustainable agricultural expansion while preventing water scarcity is developedThe methodology selects areas with high water availability while ensuring that neither local nor downstream water scarcity is triggeredAn application on coffee expansion in Kenya finds more areas than foreseen by policy, leaving action space for further selection criteri
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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