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Featured researches published by Steven J. Vanek.


Proceedings of the National Academy of Sciences of the United States of America | 2014

Obstacles to integrated pest management adoption in developing countries

Soroush Parsa; Stephen Morse; Alejandro Bonifacio; Tim Chancellor; Bruno Condori; Verónica Crespo-Pérez; Shaun L. A. Hobbs; Jürgen Kroschel; Malick N. Ba; François Rebaudo; Stephen Sherwood; Steven J. Vanek; Emile Faye; Mario Herrera; Olivier Dangles

Significance Integrated pest management (IPM) has been the dominant crop protection paradigm promoted globally since the 1960s. However, its adoption by developing country farmers is surprisingly low. This article reports 51 potential reasons why, identified and prioritized by hundreds of IPM professionals and practitioners around the world. Stakeholders from developing countries prioritized different adoption obstacles than those from high-income countries. Surprisingly, a few of the obstacles prioritized in developing countries appear to be overlooked by the literature. We suggest that a more vigorous analysis and discussion of the factors discouraging IPM adoption in developing countries may accelerate the progress needed to bring about its full potential. Despite its theoretical prominence and sound principles, integrated pest management (IPM) continues to suffer from anemic adoption rates in developing countries. To shed light on the reasons, we surveyed the opinions of a large and diverse pool of IPM professionals and practitioners from 96 countries by using structured concept mapping. The first phase of this method elicited 413 open-ended responses on perceived obstacles to IPM. Analysis of responses revealed 51 unique statements on obstacles, the most frequent of which was “insufficient training and technical support to farmers.” Cluster analyses, based on participant opinions, grouped these unique statements into six themes: research weaknesses, outreach weaknesses, IPM weaknesses, farmer weaknesses, pesticide industry interference, and weak adoption incentives. Subsequently, 163 participants rated the obstacles expressed in the 51 unique statements according to importance and remediation difficulty. Respondents from developing countries and high-income countries rated the obstacles differently. As a group, developing-country respondents rated “IPM requires collective action within a farming community” as their top obstacle to IPM adoption. Respondents from high-income countries prioritized instead the “shortage of well-qualified IPM experts and extensionists.” Differential prioritization was also evident among developing-country regions, and when obstacle statements were grouped into themes. Results highlighted the need to improve the participation of stakeholders from developing countries in the IPM adoption debate, and also to situate the debate within specific regional contexts.


Annals of the American Association of Geographers | 2017

Mountain Ecology, Remoteness, and the Rise of Agrobiodiversity: Tracing the Geographic Spaces of Human–Environment Knowledge

Karl S. Zimmerer; Hildegardo Córdova-Aguilar; Rafael Mata Olmo; Yolanda Jiménez Olivencia; Steven J. Vanek

We use an original geographic framework and insights from science, technology, and society studies and the geohumanities to investigate the development of global environmental knowledge in tropical mountains. Our analysis demonstrates the significant relationship between current agrobiodiversity and the elevation of mountain agroecosystems across multiple countries. We use the results of this general statistical model to support our focus on mountain agrobiodiversity. Regimes of the agrobiodiversity knowledge of scientists, government officials, travelers, and indigenous peoples, among others, interacting in mountain landscapes have varied significantly in denoting geographic remoteness. Knowledge representing pre-European mountain geography and diverse food plants in the tropical Andes highlighted their centrality to the Inca Empire (circa 1400–1532). The notion of semiremoteness, geographic valley–upland differentiation, and the similitude-and-difference knowledge mode characterized early Spanish imperial rule (1532–1770). Early modern accounts (1770–1900) amplified the remoteness of the Andes as they advanced global ecological sciences, knowledge standardization, and racial representations of indigenous people as degraded, with scant attention to Andean agriculture and food. Global agrobiodiversity knowledge increasingly drew on corresponding representations of mountain remoteness. Our integration of the biogeophysical–social sciences with the geohumanities reveals distinctive geographies of agrobiodiversity knowledge. Assumed remoteness of mountain agrobiodiversity is not inherent but rather is actively formed in relation to global societies and knowledge systems and is thus relational. Connectivity and claims to territorial and indigenous autonomy distinguish newly emergent characteristics of agrobiodiversity. The multifunctionality and political geography of agrobiodiversity are integral to current mountain environments, societies, and sustainability.


Journal of Microbial & Biochemical Technology | 2016

Pore-Size and Water Activity Effects on Survival of Rhizobium tropici inBiochar Inoculant Carriers

Steven J. Vanek; Janice E. Thies; Bing Wang; Kelly Hanley; Johannes Lehmann

Research examining biochar (pyrolyzed biomass) as a microbial inoculant carrier may enable broader use of inoculant microbes and elucidate relationships between non-spore forming bacteria, such as rhizobia, and their microhabitats in carriers and soils. We tested 32 biochars as habitat for Rhizobium tropici (CIAT 899) to quantify the effects of pore size distribution, chemical characteristics and clay addition on bacterial abundance, in both in sixmonth storage incubations at 27°C, and under drying conditions. Pressure plate measurements and micrographic analysis yielded correlated estimates of mean macropore (0.3-30 μm) size in the different biochar carriers (r=0.80, p<0.0001). Macropore size was assigned to the first principal component of variation in biochar properties, along with mineral content derived from plant feedstocks. Under moist storage conditions, a number of biochars were equivalent to peat as microbial carriers. Rhizobium tropici abundance in these storage incubations exhibited a quadratic dependence on biochar pore size (p<0.001) with maximal abundance at a macropore size of 13.6 μm (pressure plate) or 10.1 μm (micrographs). Abundance was lower for biochars with higher ASTM volatile content (p<0.001) and was increased by plant feedstock derived mineral content in the biochars (p<0.01). Goethite and Montmorillonite additions to biochar before pyrolysis increased macropores of size <0.3 μm. Added Goethite reduced bacterial survival, while montmorillonite increased R. tropici abundance in a large-pored pine biochar by 10 times (p<0.05), and improved its survival between two and 11 times (p<0.001) in four biochars after drying for 10 days. We conclude that optimizing pore size distribution and chemical properties of biochars is a promising strategy to produce carrier materials that are as effective as mined irradiated peat for non-spore forming bacteria such as R. tropici.


Ecology and Society | 2018

Smallholder telecoupling and potential sustainability

Karl S. Zimmerer; Eric F. Lambin; Steven J. Vanek

Smallholders are crucial for global sustainability given their importance to food and nutritional security, agriculture, and biodiversity conservation. Worldwide smallholders are subject to expanded telecoupling whereby their social-ecological systems are linked to large-scale socioeconomic and environmental drivers. The present research uses the synthesis of empirical evidence to demonstrate smallholder telecoupling through the linkages stemming from the global-level integration of markets (commodity, labor, finance), urbanization, governance, and technology. These telecoupling forces are often disadvantageous to smallholders while certain conditions can contribute to the potential sustainability of their social-ecological systems. Case studies were chosen to describe sustainability opportunities and limits involving smallholder production and consumption of high-agrobiodiversity Andean maize amid telecoupled migration (Bolivia), the role of international eco-certification in smallholder coffee-growing and agroforests (Colombia), smallholder organic dairy production in large-scale markets and technology transfer (upper Midwest, U.S.A.), and smallholders’ global niche commodity production of argan oil (Morocco). These case studies are used to identify the key challenges and opportunities faced by smallholders in telecoupling and to develop a conceptual framework. This framework specifies the integrated roles of global systems together with influential public and private institutions operating at multiple scales including the national level. The framework also integrates the local dynamics of smallholders’ multiple land use units and their socioeconomic and environmental variation. Spatial spillover effects in smallholder landscapes are an additional element. This framework further establishes the unRomantic, nonteleological, and antifetishistic view of smallholders. It provides specific insights on the multilevel dynamics of smallholder telecoupling and potential sustainability opportunities that can strengthen livelihoods, biodiversity conservation, and food and nutritional security. These insights are concluded to be valuable to environmental, agricultural, and food scientists and scholars (both biogeophysical sciences and social sciences), policy makers, institutional analysts, development specialists and practitioners, social justice activists, and others seeking to advance global sustainability including sustainable development.


Experimental Agriculture | 2016

INTEGRATING SCIENTIFIC AND LOCAL SOILS KNOWLEDGE TO EXAMINE OPTIONS BY CONTEXT INTERACTIONS FOR PHOSPHORUS ADDITION TO LEGUMES IN AN ANDEAN AGROECOSYSTEM

Steven J. Vanek; Laurie E. Drinkwater

This research sought to link Andean soil knowledge and farmer categorization of soil fertility to soil science characterization of soils, and use these to understand the impacts of phosphorus (P) fertilization of legumes using rock phosphate and soluble P fertilizer in 17 smallholder-managed sites with varying soil properties. We found that farmer high/low categorization of soils corresponded to soil P fertility and distance from farmer dwellings. Measures of soil P fertility also were inversely related to mycorrhizal colonization of vetch roots and directly related to the potential for P release by legume residues (C:P ratio). However, particular soil properties (texture and calcium phosphate pools) were better in explaining the response of legume biological nitrogen fixation to P addition, with maximal impacts in low-clay soils and soils with low calcium phosphates, as assessed with a dilute HCl extraction. In these conducive contexts, legume BNF increased 67 and 150% for RP and TSP, respectively ( p p p


The International Journal of Environmental, Cultural, Economic, and Social Sustainability: Annual Review | 2010

Climate Change in the High Andes:implications and adaptation strategies for small-scale farmers

Carlos Perez; Claire Nicklin; Olivier Dangles; Steven J. Vanek; Stephen Sherwood; Stephan Halloy; Karen A. Garrett; Gregory A. Forbes


Current Opinion in Environmental Sustainability | 2015

Sustainable smallholder intensification in global change? Pivotal spatial interactions, gendered livelihoods, and agrobiodiversity

Karl S. Zimmerer; Judith Carney; Steven J. Vanek


Plant and Soil | 2015

Phosphorus availability to beans via interactions between mycorrhizas and biochar

Steven J. Vanek; Johannes Lehmann


Advances in Agronomy | 2012

Pathways to Agroecological Intensification of Soil Fertility Management by Smallholder Farmers in the Andean Highlands

Steven J. Fonte; Steven J. Vanek; Pedro Oyarzun; Soroush Parsa; D. Carolina Quintero; Idupulapati M. Rao; Patrick Lavelle


Plant and Soil | 2016

Phosphorus availability from bone char in a P-fixing soil influenced by root-mycorrhizae-biochar interactions

Marie J. Zwetsloot; Johannes Lehmann; Taryn L. Bauerle; Steven J. Vanek; Rachel Hestrin; Abebe Nigussie

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Karl S. Zimmerer

Pennsylvania State University

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Steven J. Fonte

Colorado State University

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Stephen Sherwood

Wageningen University and Research Centre

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Olivier Dangles

Centre national de la recherche scientifique

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Soroush Parsa

International Center for Tropical Agriculture

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Gregory A. Forbes

International Potato Center

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D. Carolina Quintero

International Center for Tropical Agriculture

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