12,310 research outputs found
Environmental and biodiversity impacts of organic farming in the hills and uplands of Wales
1. Organic farming is based on principles of co-existence with natural systems, the minimisation of pollution and damage to the environment, and the promotion of the health of soil, plant and animal to produce healthy food with high standards of animal welfare and respect for the wider social and ecological impacts of the agricultural system.
2. Organic Farming has become an important aspect of EU agri-environment policy. Since the implementation of EC Reg. 2078/92 the EU promotes organic farming explicitly on its positive effects on the environment.
3. The environmental and biodiversity benefits of organic systems in the lowlands for mixed farming is generally accepted (Shepherd, 2003) but similar benefits for upland systems have not been identified. This report has been produced by OCW with funding from CCW to address this gap. Where relevant, means to ensure the beneficial impacts through changes to agri-environment schemes, organic standards, and education and dissemination are identified.
4. Hill and uplands are characterised as areas over 200m above sea level where the physical landscape results in production constraints.
5. Biodiversity losses linked to changes in hill and upland agriculture include the erosion of genetic diversity in farmed livestock and crops as well as in wildlife and flora, a reduction in habitat, soil and wildlife diversity and the loss of local knowledge and farming culture.
6. The organic approach to sustainable agriculture in hill or upland systems is through the use of multi species swards and mixed stocking.
7. The report identifies potential points of difference between organic and conventional management practices with regard to hill and upland farming and highlights research requirements to confirm or explore those potentials.
8. Conventional farms can adopt any or all of the practices of the organic farming system, but the engagement with the entire system and annual inspections are specific to the organic farmer.
9. The impacts are not just determined by the system of organic regulations and but also by the management ability and technical skills of the farmer and workers.
10. The practices on organic livestock farms identified that may differ from conventional and have direct biodiversity or environmental impacts are: lower stocking rates (overall manure loading maximum of 170kg/N/ha/yr); an adjustment of the stocking balance (increasing ratio of cattle to sheep); keeping indigenous breeds and strains adapted to the environmental conditions on the farm; limitation on products to control external parasites; reduction and restriction on the use of prophylactic veterinary medicines; the use of foragebased diets; storage and use of slurries, manures and composts, and constraints on the import and export of nutrients.
11. Organic practices in management of grassland and crops identified that may differ from conventional and have direct biodiversity or environmental impacts are: cessation of N fertiliser use; restriction on P & K use; use of lime to maintain pH; use of clovers and herbs in grass leys; cessation of use of chemical pesticides and all herbicides; mechanical and manual weed control and sensitive and timely cultivations; the use of mixed farm systems and rotations on in-bye land; the use of cover crops and undersowing; the use of green manures.
12. Organic regulations do not require habitat creation, but standards state, “that concern for the environment should manifest”…“in high standards of conservation management throughout the organic holding”.
Discussion
13. Apart from practices that impact directly on biodiversity or the environment, each management decision on the farm will have knock-on effects that have their own consequences, for example welfare standards for livestock require bedding materials and greater housing space.
14. Organic farms operating solely in the hills and uplands can only be part of a system. Use of in-bye land or having a relationship with lowland holdings to provide winter-feed and forage is necessary to comply with regulations. This will increase the amount of lowland managed organically, bringing widely recognised environmental benefits.
15. Organic agriculture is, by legal definition, a system of production and is based on principles and uses practices adopted to optimise the health of the system. Any farmer may adopt individual practices, and the Tir Gofal scheme provides an opportunity for farmers to provide positive conservation measures, whether conventional or organic. Farming under the EU Regulation defining Organic farming provides assurance to the end consumer that the system used to produce or process the food product was according to that system. This provides a reliable means for consumers to support a system of agriculture that fits more closely with their expectations than intensive systems.
16. Any advantages of lower stocking rates and mixed stocking will only be maintained while organic farms are viable. Organic labelling provides an opportunity for consumers to make a positive choice for high welfare, environmentally benign systems; however the difficulties of marketing, the lack of consumer awareness of food production issues and unwillingness to pay are barriers to access to premium markets for many producers.
Conclusions:
17. The potential benefits of individual practices outlined in the document are often clear, but there are currently few data to confirm the extent of some of the practices that may have most beneficial impact. The need for data on actual practices of the organic farmers in the hills and uplands is therefore highlighted.
18. Few Standards changes are recommended, however the monitoring of derogations to standards and use of restricted veterinary inputs is recommended.
19. Research and development needs, technical, education and dissemination, and agri-environment policy issues which may establish, ensure, or enhance the environmental and biodiversity impacts of organic farming in the hills and uplands are outlined.
20. Infrastructure work to integrate hill and upland and lowland systems is necessary to facilitate organic farming in the uplands; this may assist the viability of lowland organic holdings: the environmental benefits of which are established
Resource efficiency and economic implications of alternatives to surgical castration without anaesthesia
This paper presents an analysis of the economic implications of alternative methods to surgical castration without anaesthesia. Detailed research results on the economic implications of four different alternatives are reported. castration with local anaesthesia, castration with general anaesthesia, immunocastration and raising entire males. The first three alternatives have been assessed for their impact on pig production costs in the most important pig-producing Member States of the EU. The findings on castration with anaesthesia show that cost differences among farms increase if the anaesthesia cannot be administered by farmers and when the veterinarian has to be called to perform it. The cost of veterinarian service largely affects the total average costs, making this solution economically less feasible in small-scale pig farms. In all other farms, the impact on production costs of local anaesthesia is however limited and does not exceed 1 (sic)ct per kg. General anaesthesia administered by inhalation or injection of Ketamin in combination with a sedative (Azaperone, Midazolan) is more expensive. These costs depend heavily on farm size, as the inhalation equipment has to be depreciated on the largest number of pigs possible. The overall costs of immunocastration - including the cost of the work load for the farmer - has to be evaluated against the potential benefits derived from higher daily weight gain and feed efficiency in comparison with surgical castrates. The economic feasibility of this practice will finally depend on the price of the vaccine and on consumer acceptance of immunocastration, The improvement in feed efficiency may compensate almost entirely for the cost of vaccination. The main advantages linked to raising entire males are due to the higher efficiency of feed conversion, to the better growth rate and to the higher leanness of carcass. A higher risk of boar taint on the slaughter line has to be accounted for Raising entire males should not generate more than 2.5% of boar taint among slaughter pigs, in order to maintain the considerable economic benefits of better feed efficiency of entire males with respect to castrates
Unified Approach to Thermodynamic Bethe Ansatz and Finite Size Corrections for Lattice Models and Field Theories
We present a unified approach to the Thermodynamic Bethe Ansatz (TBA) for
magnetic chains and field theories that includes the finite size (and zero
temperature) calculations for lattice BA models. In all cases, the free energy
follows by quadratures from the solution of a {\bf single} non-linear integral
equation (NLIE). [A system of NLIE appears for nested BA]. We derive the NLIE
for: a) the six-vertex model with twisted boundary conditions; b) the XXZ chain
in an external magnetic field and c) the sine-Gordon-massive Thirring
model (sG-mT) in a periodic box of size \b \equiv 1/T using the light-cone
approach. This NLIE is solved by iteration in one regime (high in the XXZ
chain and low in the sG-mT model). In the opposite (conformal) regime, the
leading behaviors are obtained in closed form. Higher corrections can be
derived from the Riemann-Hilbert form of the NLIE that we present.Comment: Expanded Introduction. Version to appear in Nucl. Phys. B. 60 pages,
TeX, Uses phyzz
Sobre a relação entre o antitruste e a estratégia: onde estamos e para onde podemos ir
Neste artigo, é examinado o papel que a análise estratégica tem desempenhado no antitruste e são discutidos novos caminhos. A fim de alcançar este objetivo, o trabalho apresenta duas direções. Inicialmente, realiza-se a revisão do debate atual sobre a relação entre antitruste e estratégia. Defende-se que grande parte da discussão contemporânea sobre o assunto se baseia em abordagens econômicas tradicionais de estratégia, o que leva à desconsideração do papel da heterogeneidade da firma na dinâmica competitiva. Na segunda parte do artigo, é esboçada uma abordagem de antitruste fundamentada na visão baseada em recursos. Esta abordagem é particularmente útil para examinar as condições de rivalidade do mercado, sendo um complemento – e não necessariamente um substituto – à análise econômica antitruste tradicional.En este artículo se evalúa el papel que el análisis estratégico ha jugado en la defensa de la competencia y se discuten nuevos caminos. Para ello, se presentan dos direcciones. Inicialmente, se lleva a cabo una revisión del actual debate sobre la relación entre la defensa de la competencia y la estrategia. Se argumenta que gran parte de la discusión contemporánea sobre el tema se basa en los enfoques económicos tradicionales de estrategia, lo que lleva a ignorar el papel de la heterogeneidad de la organización en la dinámica competitiva. En la segunda parte del artículo, se describe un enfoque de antimonopolio que se apoya en la visión basada en recursos. Este enfoque es particularmente útil para examinar las condiciones de competencia del mercado, y puede complementar – y no necesariamente reemplazar – el análisis económico antitrust tradicional.In this paper, I examine the role that strategic analysis has played on antitrust and discuss new analytical venues. In order to accomplish this goal, the paper presents two directions. Initially, I undertake a review of the current debate between antitrust and strategy. I argue that much of the contemporary discussion on the subject is founded on traditional economic approaches to strategy, what leads to the disregard of the role of firm heterogeneity in competitive dynamics. In the second part of the paper, I sketch an approach to antitrust based on the resource-based view of strategy. This approach is particularly useful in examining the conditions of market rivalry, being a complement – not necessarily a substitute – to the traditional antitrust economic analysis
Genes, Economics, and Happiness
We explore the influence of genetic variation on subjective well-being by employing a twin design and genetic association study. In a nationally-representative twin sample, we first show that about 33% of the variation in life satisfaction is explained by genetic variation. Although previous studies have shown that baseline happiness is significantly heritable, little research has considered molecular genetic associations with subjective well-being. We study the relationship between a functional polymorphism on the serotonin transporter gene (5-HTTLPR) and life satisfaction. We initially find that individuals with the longer, transcriptionally more efficient variant of this genotype report greater life satisfaction (n=2,545, p=0.012). However, our replication attempts on independent samples produce mixed results indicating that more work needs to be done to better understand the relationship between this genotype and subjective well-being. This work has implications for how economists think about the determinants of utility, and the extent to which exogenous shocks might affect individual well-being.life satisfaction, twin study, genetic association, serotonin transporter gene, 5-HTTLPR, rs2020933
Genes, Economics and Happiness
A major finding from research into the sources of subjective well-being is that individuals exhibit a "baseline" level of happiness. We explore the influence of genetic variation by employing a twin design and genetic association study. We first show that about 33% of the variation in happiness is explained by genes. Next, using two independent data sources, we present evidence that individuals with a transcriptionally more efficient version of the serotonin transporter gene (SLC6A4) report significantly higher levels of life satisfaction. These results are the first to identify a specific gene that is associated with happiness and suggest that behavioral models benefit from integrating genetic variation.wellbeing, socio-demographics, happiness, genetics, life satisfaction
The "Unfriending" Problem: The Consequences of Homophily in Friendship Retention for Causal Estimates of Social Influence
An increasing number of scholars are using longitudinal social network data
to try to obtain estimates of peer or social influence effects. These data may
provide additional statistical leverage, but they can introduce new inferential
problems. In particular, while the confounding effects of homophily in
friendship formation are widely appreciated, homophily in friendship retention
may also confound causal estimates of social influence in longitudinal network
data. We provide evidence for this claim in a Monte Carlo analysis of the
statistical model used by Christakis, Fowler, and their colleagues in numerous
articles estimating "contagion" effects in social networks. Our results
indicate that homophily in friendship retention induces significant upward bias
and decreased coverage levels in the Christakis and Fowler model if there is
non-negligible friendship attrition over time.Comment: 26 pages, 4 figure
Formal vs self-organised knowledge systems: a network approach
In this work we consider the topological analysis of symbolic formal systems
in the framework of network theory. In particular we analyse the network
extracted by Principia Mathematica of B. Russell and A.N. Whitehead, where the
vertices are the statements and two statements are connected with a directed
link if one statement is used to demonstrate the other one. We compare the
obtained network with other directed acyclic graphs, such as a scientific
citation network and a stochastic model. We also introduce a novel topological
ordering for directed acyclic graphs and we discuss its properties in respect
to the classical one. The main result is the observation that formal systems of
knowledge topologically behave similarly to self-organised systems.Comment: research pape
Devo ir ao tribunal?: o papel do Judiciário nas disputas entre pecuaristas e a indústria frigorífica no Brasil
El principal objetivo en este estudio es examinar el papel del poder judicial en la resolución de conflictos entre ganaderos y la industria frigorífica en Brasil. Para ello, se investiga la compra de ganado para matadero en el estado de Mato Grosso do Sul (centro oeste de Brasil) en tres etapas. Inicialmente, se describe el patrón de las transacciones entre los ganaderos y la industria frigorífica, lo que permite identificar un vacío de garantías a lo largo de la cadena de suministro. A continuación, se presentan evidencias de que dicho vacío de garantías puede dar lugar a conflictos legales relativos a falta de pago, lo que es, efectivamente, el tema predominante en el poder judicial. Finalmente, se investiga el papel del poder judicial en la resolución de dichos conflictos. Los resultados sugieren que los productores tienen, en general, poca confianza en el sistema legal, lo que indica un posible papel que mecanismos informales juegan en este sistema agroindustrial. Se concluye el estudio con sugerencias de estrategias públicas y privadas.The main objective of this perspective paper is to analyze the role of the judiciary in resolving conflicts between cattle raisers and meatpacking firms in Brazil. Looking at the transaction for the acquisition of cattle for slaughter in the state of Mato Grosso do Sul (the central-western region of Brazil), the analysis encompasses three steps. First, the authors describe the transaction pattern between cattle raisers and meatpacking firms, identifying a guarantee vacuum within the supply chain. Secondly, the authors present evidence that the guarantee vacuum may give rise to legal conflicts of non-payment, which are indeed prevalent in disputes that reach the courts. Finally, the role of the judiciary in resolving these conflicts is investigated. Results suggest that, on average, producers have little confidence in the legal system, indicating the potential function that informal mechanisms may play in the supply chain. The paper concludes by suggesting some implications for public and private strategies.A pesquisa apresentada neste artigo tem por principal objetivo analisar o papel do Judiciário na solução de conflitos entre os pecuaristas e a indústria frigorífica no Brasil. Para tanto, investiga-se a aquisição de gado para abate no estado de Mato Grosso do Sul (Centro-Oeste do Brasil), em três etapas. Inicialmente, descreve-se o padrão da transação entre os pecuaristas e a indústria frigorífica, identificando um vácuo de garantias ao longo da cadeia de suprimentos. Em sequência, apresentam-se evidências de que esse vácuo de garantias pode dar margem a conflitos legais de não pagamento, o que, de fato, é a questão prevalente no Judiciário. Finalmente, investiga-se o papel do Judiciário para solucionar esses conflitos. Os resultados sugerem que, em média, os produtores têm baixa confiança no sistema legal, indicando um papel potencial que mecanismos informais desempenham nesse sistema agroindustrial. Conclui-se com sugestões de estratégias públicas e privadas
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