8,258 research outputs found
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Towards a method for the economic evaluation of environmental indicators in UK Integrated Arable Farming Systems
Integrated Arable Farming Systems (IAFS), which involve a reduction in the use of off-farm inputs, are attracting considerable research interest in the UK. The objectives of these systems experiments are to compare their financial performance with that from conventional or current farming practices. To date, this comparison has taken little account of any environmental benefits (or disbenefits) of the two systems. The objective of this paper is to review the assessment methodologies available for the analysis of environmental impacts. To illustrate the results of this exercise, the methodology and environmental indicators chosen are then applied to data from one of the LINK - Integrated Farming Systems experimental sites. Data from the Pathhead site in Southern Scotland are used to evaluate the use of invertebrates and nitrate loss as environmental indicators within IAFS. The results suggest that between 1992 and 1995 the biomass of earthworms fell by 28 kg per hectare on the integrated rotation and rose by 31 kg per hectare on the conventional system. This led to environmental costs ranging between £2.24 and £13.44 per hectare for the integrated system and gains of between £2.48 and £14.88 for the conventional system. In terms of nitrate, the integrated system had an estimated loss of £72.21 per hectare in comparison to £149.40 per hectare on the conventional system. Conclusions are drawn about the advantages and disadvantages of this type of analytical framework.
Keywords: Farming systems; IAFS; Environmental valuation; Economics; Earthworms; Nitrates; Soil faun
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Integrated Arable Farming Systems and their potential uptake in the UK
Integrated Arable Farming Systems are examined from the perspective of the farmer considering the use of such techniques, and data are presented which suggest that the uptake of the approach may expose the manager to a greater degree of risk. Observations are made about the possible uptake of such systems in the UK and the implications this may have for agricultural and environmental policy in general
Negative impacts of felling in exotic spruce plantations on moth diversity mitigated by remnants of deciduous tree cover
Moths are a vital ecosystem component and are currently undergoing extensive and severe declines across multiple species, partly attributed to habitat alteration. Although most remaining forest cover in Europe consists of intensively managed plantation woodlands, no studies have examined the influence of management practices on moth communities within plantations. Here, we aimed to determine: (1) how species richness, abundance, diversity of macro and micro moths in commercial conifer plantations respond to management at multiple spatial scales; (2) what the impacts of forest management practices on moth diversity are, and (3) how priority Biodiversity Action Plan (BAP) species respond to management. BAP species were selected as they represent formerly widespread and common species, which have undergone substantial declines in the UK and Europe. We assessed moth communities in three conifer plantations in Northern England and Scotland by light trapping, combining local (e.g. age of planting) and landscape level (e.g. proximity to felled areas) characteristics to evaluate the impacts of forest management on moths. We found no relationship between local factors and moth richness, abundance and diversity but the amount of clear felling in the surrounding landscape had a strongly negative correlation. In contrast, the amount and proximity of broadleaf cover in the surrounding landscape positively influenced macro moth richness and abundance. For six BAP species, abundances were lower close to felled areas but increased with the size of adjacent broadleaf patches. We conclude that clear felling negatively affects moths, probably through alteration of habitats, the loss of larval host plants, and by limiting dispersal. A shift to continuous cover and maintaining broadleaf tree cover within plantations will greatly enhance their value for moth communities
Low-Temperature Long-Time Simulations of Ising Ferromagnets using the Monte Carlo with Absorbing Markov Chains method
The Monte Carlo with Absorbing Markov Chains (MCAMC) method is introduced.
This method is a generalization of the rejection-free method known as the
-fold way. The MCAMC algorithm is applied to the study of the very
low-temperature properties of the lifetime of the metastable state of Ising
ferromagnets. This is done both for square-lattice and cubic-lattice
nearest-neighbor models. Comparison is made with exact low-temperature
predictions, in particular the low-temperature predictions that the metastable
lifetime is discontinuous at particular values of the field. This discontinuity
for the square lattice is not seen in finite-temperatures studies. For the
cubic lattice, it is shown that these `exact predictions' are incorrect near
the fields where there are discontinuities. The low-temperature formula must be
modified and the corrected low-temperature predictions are not discontinuous in
the energy of the nucleating droplet.Comment: Submitted to Computer Physics Communicatinos, for proceedings of the
Conference CCP2001, 4 figure
Update on form factor at zero-recoil using the Oktay-Kronfeld action
We present an update on the calculation of
semileptonic form factor at zero recoil using the Oktay-Kronfeld bottom and
charm quarks on flavor HISQ ensembles generated by the MILC
collaboration. Preliminary results are given for two ensembles with and fm and MeV. Calculations have been done
with a number of valence quark masses, and the dependence of the form factor on
them is investigated on the fm ensemble. The excited state is
controlled by using multistate fits to the three-point correlators measured at
4--6 source-sink separations.Comment: 7 pages and 4 figures. Talk at The 36th Annual International
Symposium on Lattice Field Theory - LATTICE201
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