La agricultura familiar en la región pampeana argentina. La utilización de los factores de producción y su relación con nuevas dinámicas familiares

Este artículo tiene un doble objetivo. Por un lado, conocer cuál es la relación que guarda la agricultura familiar de la región pampeana argentina con los distintos factores de producción intentando verificar si es factible encontrar en estas unidades una forma particular de organizar el trabajo, relacionarse con el recurso tierra y/o capitalizarse (invertir en tecnología) que diferencie a la agricultura familiar de otras formas de producción. Por el otro, indagar acerca de los procesos de cambio que se han venido produciendo en las dinámicas de estas familias, con comportamientos y valores "modernos" característicos de familias urbanas, para analizar sus efectos sobre la organización de la unidad productiva. Todo ello, en el contexto de esta región cada vez más especializada en la producción agrícola e inserta en circuitos de comercialización mundiales. En este sentido, primero se observan los rasgos que presenta el vínculo de este tipo de unidades con los distintos factores de producción (tierra, capital y trabajo) y, a continuación, se propone un análisis acerca de las modificaciones atravesadas por las familias involucradas que han venido influyendo en la forma de tomar decisiones por parte de la unidad productiva. En cuanto al abordaje metodológico, se realizó una encuesta a productores familiares a partir de una muestra del total de establecimientos agropecuarios en el partido de Junín, ubicado en el noroeste de la provincia de Buenos Aires, Argentina, así como también se realizaron entrevistas a productores y a esposas e hijos de productores del partido.

De chacareros a rentistas : Trayectorias de abandono de la actividad agropecuaria en el SO bonaerense (Puán y Adolfo Alsina, 1988-2012)

En este artículo se analizan las experiencias de un grupo de familias de los partidos de Puán y Adolfo Alsina (ubicados en el sudoeste de la provincia de Buenos Aires), que hacia fines de los los años 1980 organizaban su actividad en torno al trabajo de lo miembros de la familia y que, en diferentes puntos de los últimos treinta años, abandonaron la producción y se transformaron en rentistas. A partir de un abordaje cualitativo se indaga en las razones que llevaron a esa situación, teniendo en cuenta aspectos objetivos y subjetivos de los procesos. En esa línea, se analizan los factores involucrados en las trayectorias de retiro de la actividad y los efectos que estos procesos han tenido sobre las identidades y perspectivas de los entrevistados

Determination of ages and fossil Coleoptera fauna from eight sites in the London region

These data sets report the fossil beetle assemblages identified from the Mesolithic to Late Bronze Age at eight sites in the London region. All but one of the study sites are within 2 km of the modern course of the Thames. The sites produced 128 faunal assemblages that yielded 218 identified species in 41 families of Coleoptera (beetles).  Beetle faunas of Mesolithic age indicate extensive wetlands near the Thames, bordered by rich deciduous woodlands. The proportion of woodland species declined in the Neolithic, apparently because of the expansion of wetlands, rather than because of human activities. The Early Bronze Age faunas contained a greater proportion of coniferous woodland and aquatic (standing water) species. An increase in the dung beetle fauna indicates the presence of sheep, cattle and horses, and various beetles associated with crop lands demonstrate the local rise of agriculture, albeit several centuries after the beginnings of farming in other regions of Britain. Late Bronze Age faunas show the continued development of agriculture and animal husbandry along the lower Thames. About 33% of the total identified beetle fauna from the London area sites have limited modern distributions or are extinct in the U.K. Some of these species are associated with the dead wood found in primeval forests; others are wetland species whose habitat has been severely reduced in recent centuries. The third group is stream-dwelling beetles that require clean, clear waters and river bottoms.

Collisional Formation and Modeling of Asteroid Families

In the last decade, thanks to the development of sophisticated numerical codes, major breakthroughs have been achieved in our understanding of the formation of asteroid families by catastrophic disruption of large parent bodies. In this review, we describe numerical simulations of asteroid collisions that reproduced the main properties of families, accounting for both the fragmentation of an asteroid at the time of impact and the subsequent gravitational interactions of the generated fragments. The simulations demonstrate that the catastrophic disruption of bodies larger than a few hundred meters in diameter leads to the formation of large aggregates due to gravitational reaccumulation of smaller fragments, which helps explain the presence of large members within asteroid families. Thus, for the first time, numerical simulations successfully reproduced the sizes and ejection velocities of members of representative families. Moreover, the simulations provide constraints on the family dynamical histories and on the possible internal structure of family members and their parent bodies.

Development of land rental market and its effect on household farming in rural China : an empirical study in Zhejiang Province

This paper investigates the impact of land rental market development on the efficiency of labor allocation and land utilization in rural China. To test the hypothesis that the shadow wage of a rent-in household with limited off-farm opportunities will increase with the development of a land rental market for households, a statistical comparison between the shadow wage and the estimated market wage was conducted. The results showed that the shadow wage for both rent-in households and non-rent-in households was significantly lower than the market wage, but that the wage for the rent-in households was statistically higher than that for non-rent-in households in Fenghua and Deqing, the two counties surveyed in this study. In addition, the estimated marginal product of farmland for rent-in households was statistically higher than the actual land rent that those households paid, while a null hypothesis that the actual rental fee accepted by rent-out households is equivalent to the marginal product of farmland for those households was not rejected in Fenghua county where land transactions by mutual agreement were more prevalent. These results indicate that the development of the land rental market facilitates the efficiency of labor allocation and farmland utilization in rural China.

Farming strategy of African smallholder farmers in transition from traditional to alternative agriculture : the case of the Nupe in central Nigeria

It is worthwhile to understand farming strategies of smallholder farmers in sub-Saharan Africa, especially those of farmers who are in transition from traditional to alternative agriculture in terms of adoption of innovative technologies. In a case study of inland valleys in central Nigeria, we investigated the farming strategy of Nupe farmers who have a long-term tradition of wet rice cultivation and indigenous methods of land preparation for soil, water and weed management. In this region, a new method of land preparation has recently been introduced along with a recommendation to use improved seeds and chemical fertilizers. Our findings reveal that Nupe farmers directly sow traditional seeds and apply a marginal amount of fertilizer to paddy plots prepared by labor-saving methods on drought-prone hydromorphic valley fringes and flood-susceptible valley bottoms, whereas they preferentially transplanted improved seedlings and applied a relatively large quantity of fertilizer to paddy fields prepared by a labor-intensive and mechanized method on a valley position where they can access to optimum water condition (less risky against the drought and flood).

Plant protein-coding gene families: emerging bioinformatics approaches

Protein-coding gene families are sets of similar genes with a shared evolutionary origin and, generally, with similar biological functions. In plants, the size and role of gene families has been only partially addressed. However, suitable bioinformatics tools are being developed to cluster the enormous number of sequences currently available in databases. Specifically, comparative genomic databases promise to become powerful tools for gene family annotation in plant clades. In this review, I evaluate the data retrieved from various gene family databases, the ease with which they can be extracted and how useful the extracted information is.

A waypoint-based mission planner for a farmland coverage with an aerial robot - a precision farming tool

Remote sensing (RS) with aerial robots is becoming more usual in every day time in Precision Agriculture (PA) practices, do to their advantages over conventional methods. Usually, available commercial platforms providing off-the-shelf waypoint navigation are adopted to perform visual surveys over crop fields, with the purpose to acquire specific image samples. The way in which a waypoint list is computed and dispatched to the aerial robot when mapping non empty agricultural workspaces has not been yet discussed. In this paper we propose an offline mission planner approach that computes an efficient coverage path subject to some constraints by decomposing the environment approximately into cells. Therefore, the aim of this work is contributing with a feasible waypoints-based tool to support PA practices