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We reviewed studies aimed at understanding functional relationships between weeds and arthropods in agroecosystems as influenced by biodiversity at different scales, with the main goal of highlighting gaps in knowledge, research methods and approaches. We first addressed: (i) the regulation of arthropod communities by weed diversity at genetic, species and habitat levels, (ii) the regulation of weed communities by arthropods through seed predation and dispersal and (iii) belowground weed-insect interactions. We then focussed on methodologies to study weed-arthropod interactions in agricultural landscapes and discuss techniques potentially available for data analysis and the importance of joint weed-arthropod trend detection. Lastly, we discuss the implications of research findings for biodiversity conservation policies (agri-environmental schemes) and suggest some priorities for future work. Results showed that to date research has largely ignored weed-arthropod interactions in agricultural landscapes. No information is available on the role of weed genetic diversity as driver of weed-arthropod interactions, whereas studies on effects of species and habitat diversity often lack a functional perspective and ? or a spatial component. Also, information on how management of the wider agricultural biotope might express positive weed- arthropod functional interactions is scarce. Another area worth being explored is the relationship between weed-leaf ? root herbivores and beneficial arthropods. Tools for spatial data analysis might be useful for elucidating weed-arthropod interactions in agricultural landscapes, but some methodological aspects, e.g. the definition of the most appropriate experimental design and sampling scale ? frequency, must be refined. New studies on weed-arthropod interactions should encompass an explicit spatial component; this knowledge is particularly important for improving IPM ?IWM systems and designing more targeted agri-environmental schemes.

Wessex Institute of Technology;Universidad Complutense, Tenth International Conference on Modelling, Monitoring and Management of Air Pollution, Air Pollution X -- 1 July 2002 through 3 July 2002 -- Segovia -- 63138, To monitor the effect of control measures for ozone it is desirable to map the concentrations for this pollutant at regional level, in agreement with the aims of the European Framework Directive on ambient air quality assessment and management. In principle, passive sampling represents a perfect tool in the light of the Directive to map a particular area for a given pollutant and to characterise those areas where the limit values are expected to be exceeded. A simple, inexpensive diffusive sampler for ozone has been developed. The sampler was tested in a chamber study and in a field trial in the Lazio Region, where it was carried out a monitoring campaign for ozone together with sulphur dioxide and nitrogen oxides, also measured by using a diffusive sampling technique. The results obtained are reported and discussed. The sampler is capable of reliable measurements of ozone at common levels of a polluted atmosphere in urban and rural settings yielding average concentration levels over one month and beyond.

A simple, cost-effective diffusive sampler is described that is suitable for measuring parts per billion (ppb) levels of ozone and nitrogen oxides. The diffusive sampler makes use of nitrite for ozone determination whereas for nitrogen oxides and nitrogen dioxide an active carbon tissue impregnated with sodium carbonate is used. Nitrate and nitrite, the formation of which is proportional to the pollutant concentration and sampling duration, are the two species analysed, respectively. Diffusion tubes have the advantage of being a low- cost, convenient way of mapping spatial distributions and investigating long-term trends of ozone and nitrogen oxides. The method is extremely useful for assessing long-term concentrations such as the annual mean for nitrogen oxides, as required by the Daughter Directive 1999/30/EC. Field tests to validate the method have been carried out at an urban background location with co-located passive samplers and continuous measurements of O3and NOx. An application in ecological effects monitoring for ozone is also presented.

The purpose of this research is to estimate the causal and/or pre-existing causal influence of some working factors, such as the standing (position) in pelvic pain syndrome, in relation to the reduction in working performance.The research was carried out by means of an inclusive questionnaire, the purpose being to analyse anamnestic and working information. The questionnaire was proposed to a group of female sanitary staff selected in relation to their working activity.Examination of the questionnaire shows prominently the association between pelvic pain and orthostatic working activity, kept not below 4-6 hours each duty. In fact, 70% of the people selected have reported this mutual relationship.Working activities in the orthostatic position can produce pelvic pain, whose origin and intensity seem to be related to extended orthostatic working activity. The mechanism by which the upright position can produce an outbreak of pelvic pain in women seems to be linked to the compression on abdominal vessels, with slowing-down and reduction of the hematic uterine discharge.

The central issue of this study was to evaluate the economic and environmental sustainability of an organic dairy farm. We also endeavoured to provide technical information for future agricultural policies. We used a linear programming model to simulate the environmental, economic, technical and organisational farm results. We prepared two versions of the model, one for the present situation of the farm (organic version) and another for the situation prior to conversion from conventional to organic agriculture (conventional version). The objective function of the model optimises farm gross income. We present the general structure of the model and specify environmental aspects. In particular, we consider three main environmental components: nitrogen cycle into the agroecosystem, soil erosion and non-replaceable energy consumption. The results of the simulation show how the organic method achieves an economic efficiency level equal to the conventional one, due to the favourable price the farm could obtain for organic milk. Moreover the organic method generates sorne relevant environmental effects. We calculated the marginal and average production costs of environmental externalities through parametric linear programming. We suggest a new agricultural policy based on the costs of environmental externalities.

Atmospheric nitrogen compounds perform a critical role in tropospheric photochemistry and are crucial to understand the chemical and physical evolution of atmospheric pollutants in polar areas. Measurements of these species in remote areas are rare, although their relevance is well established. Sampling campaigns of gaseous and particulate atmospheric trace species were performed in Arctic and in Antarctica during three consecutive years (1997-1999), using a proper combination of annular denuders and filter pack. After sampling, the ionic species were extracted with aqueous solutions and analysed by means of ion chromatography. Quality assurance on the sampling and analytical steps allowed accurate and precise measurements of all relevant compounds, which are thought to be important to nitrogen chemistry, at very low concentration levels measured in remote atmospheres. In addition, the sampling campaigns also included a multistage low pressure impactor for the collection of particulate matter in different size regions (0.035-15.9 mm). Results obtained from these campaigns demonstrate that the minor components may be measured at levels as low as a few nanograms per cubic meter in remote atmospheres using the annular denuder technique. The reported concentrations are to be considered among the first observations of nitrogen containing compounds.