Dinâmica populacional de Bemisia tabaci biótipo B em tomate monocultivo e consorciado com coentro sob cultivo orgânico e convencional.

A mosca-branca Bemisia tabaci Biótipo B (Hemiptera: Aleyrodidae), é um herbívoro de difícil controle devido à alta plasticidade genotípica da espécie. No tomateiro pode causar danos severos principalmente pela transmissão de diversas viroses. O manejo do sistema de produção e o consórcio de culturas podem ter um efeito direto nas populações desse herbívoro, sem que seja necessária a aplicação de inseticidas. Avaliou-se a influência dos sistemas de produção orgânico e convencional e o consórcio tomate-coentro na dinâmica populacional da mosca-branca no campo experimental da Embrapa Hortaliças, de maio a setembro/06. O monitoramento dos adultos da mosca-branca e de seus inimigos naturais foi realizado utilizando-se armadilhas adesivas amarelas fixadas nas bordas e no interior das parcelas experimentais e a amostragem de ninfas foi realizada por observação direta das folhas de tomate no campo. Embora as populações ao redor dos diferentes tratamentos fossem equivalentes, a abundância de adultos de mosca-branca foi significativamente menor nas parcelas de tomate consorciado com coentro, tanto no sistema convencional como orgânico. Apenas o consórcio tomatecoentro em sistema orgânico apresentou redução significativa na quantidade de ninfas por planta em relação aos demais tratamentos. Os inimigos naturais foram significativamente mais abundantes em sistema orgânico e foi verificada uma correlação negativa da abundância dos inimigos naturais e a quantidade de ninfas por planta. A associação tomate-coentro e o manejo orgânico do agroecossistema favoreceram ao controle biológico natural da mosca-branca

Transformative Agroecology Learning in Europe: Building Consciousness, Skills and Collective Capacity for Food Sovereignty

Agroecology has been proposed as a key building block for food sovereignty. This article examines the meaning, practices and potentials of ‘transformative agroecology learning’ as a collective strategy for food system transformation. Our study is based on our qualitative and action research with the European Coordination of Via Campesina to develop the European Agroecology Knowledge Exchange Network (EAKEN). This network is linked to the global network of La Via Campesina and builds on the strong experiences and traditions of popular education in Latin American peasant movements. Rather than focusing on agroecology education as a process of individual learning, we analyse how a transformative agroecology education can be strengthened as a critical repertoire of action used by social movements to advance food sovereignty. Our analysis contributes a new theory of transformative agroecology learning based on four key characteristics or qualities: horizontalism; diálogo de saberes (wisdom dialogues); combining practical and political knowledge; and building social movement networks. While these different elements of transformative agroecology learning were present across EAKEN, they were unevenly developed and, in many cases, not systematized. The framework can help to strategically and reflexively systematize and strengthen a transformative agroecology learning approach as a key building block for food sovereignty

Urban and Peri-urban Agroforestry as Multifunctional Land Use

In this era of global changes, rapid urbanization rates, climate change impacts and growing socio-environmental concerns are negatively impacting on various aspects of urban life, such as human health and well-being, urban economy stability, biodiversity levels, land productivity and natural resources availability. In this context, cities - having become the main centres of consumption and production worldwide - need to move towards more sustainable and resilient urban development models, considering novel approaches aimed at integrating grey and green infrastructure, economic growth and environmental concerns, knowledge diffusion and poverty and hunger eradication. In this regard, the implementation of urban and peri-urban agroforestry (UPAF) systems - associated with the integration of urban food systems into urban planning - can greatly support the provision of ecosystem services to urban dwellers, thus contributing to the improvement of their livelihood through increased food and nutrition security, energy and fresh water availability, regulation of local climate, carbon sequestration, maintenance of genetic diversity, recreation opportunities and health improvement. In this sense, UPAF is emerging as a new urban practice addressed to promote sustainable land use as well as the integration between urban and rural development. However, its implementation in urban contexts presents several key challenges, such as land tenure conflicts, lack of integration with urban policies and plans and technical knowledge, as well as necessity of innovative governance models. In this context, the aim of this chapter is to outline, through a review of the relevant literature and case studies from both developed and developing countries, the benefits deriving from the implementation of UPAF systems and highlight how these practices can support the improvement of urban sustainability and resilience, particularly in terms of enhancement of provisioning, cultural, regulating and supporting ecosystem services

From vineyards to feedlots: a fund-flow scanning of sociometabolic transition in the Vallès County (Catalonia) 1860-1956-1999

We analyse the changes to agricultural metabolism in four municipalities of Vallès County (Catalonia, Iberia) by accounting for their agroecosystemfunds and flows during the socioecological transition from organic to industrial farming between the late nineteenth and twentieth centuries. The choice of three different stages in this transition allows us to observe the transformation of its funds and flows over time, the links established between them and the effect on their energy profiles.We emphasize the relevance of the integration and consistency of agroecosystem funds for energy efficiency in agriculture and their role as underlying historical drivers of this socioecological transition. While readjustment to market conditions and availability and affordability of external inputs are considered the main drivers of the transition, we also highlight the role of societal energy and nutritional transitions. An analysis of advanced organic agriculture c. 1860 reveals the great effort required to reproduce soil fertility and livestock from the internal recirculation of biomass. Meanwhile, a balance between land produce and livestock densities enabled the integration of funds, with a positive impact on energy performance. The adoption of fossil fuels and synthetic fertilizers c. 1956 reduced somewhat the pressure exerted on the land by overcoming the former dependence on local biomass flows to reproduce the agroecosystem. Yet external inputs diminished sustainability. Partial dependence on external markets existed congruently with internal crop diversity and the predominance of organic over industrial farm management. A shift towards animal production and consumption led to a new specialization process c. 1999 that resulted in crop homogenization and agroecological landscape disintegration. The energy returns of this linear feed-food livestock bioconversion declined compared to earlier mixed farming. Huge energy flows driven by a globalized economy ran through this agroecosystem, provoking deep impacts at both a local and external scale