Orographic enhancement of wet deposition in the United Kingdom: case studies and modelling

Two field experiments to observe the detailed response of wet deposition to orography in a polluted environment are reported. Rain events were classed as frontal, convective or mixed on the basis of meteorological data. Analysis of the deposition enhancement and cap cloud composition confirmed that for the frontal events the seeder-feeder effect (scavenging of cap cloud by rain drops) dominates. The greater concentration of ions in the water scavenged from the cap cloud than in the rain means that deposition is enhanced for all ions. For marine ions the scavenged water was found to be between five and six times as concentrated as the rain and for anthropogenically produced ions it was about twice as concentrated.A computational model of rainfall incorporating the seeder-feeder effect has been broadly successful in predicting enhancement although some details of the observed pattern remain to be explained.     

Quantifying the fine scale (1km × 1km) exposure,dose and effects of ozone: Part 2 estimating yield losses for agricultural crops

In Britain wheat is an important crop accounting for 41% of the total cereal production. In this study ozone concentrations for 1989 estimated as described in Part 1 of the paper are integrated with the estimated wheat distribution to derive a detailed estimate of the impact of ozone on wheat yields at a fine spatial scale (1km × 1km). These data provide estimates for calculating regional and national yield losses. The methodology can be applied to other crop species. Recent research on a range of crops has established relationships between the economic yield loss for certain crops, including wheat, and ozone exposure. Exposure is described as the accumulated exposure above a threshold experienced during the daylight hours (AOT). Critical AOT values are derived from yield exposure relationships which show linear reductions of yield loss with increasing ozone concentrations. This study has made use of land cover data from remotely sensed imagery at 25m resolution and nationally collected agricultural statistics for counties. These data were combined using an areal interpolation technique to provide more spatially articulate estimates of the location and intensity of wheat production. The results demonstrate the economic importance of ozone as a pollutant. Wheat yield losses attributed to ozone vary between different parts of the country but, for years when ozone levels are high, yield losses are likely to be significant in some areas.     

Study of Aerosol Deposition at a Wind Exposed Forest Edge Using 210Pb and 137Cs Soil Inventories

Water, Air, &; Soil Pollution - The radionuclide 210Pb derived from gaseous 222Rn present in the atmosphere becomes attached to the same aerosols as the bulk of the main pollutants sulphur and...     

Llama medicine. Conformation and soundness

Conformational problems tend to be common in llamas and alpacas. Without setting a standard, basic conformation can still be evaluated by comparing with equine conformation, especially in terms of straightness of limbs. Good conformation should evoke a sense of balance in the observer. Conformation faults predispose to unsoundness.     

Relationship between plasma insulin and triglyceride concentrations in hypertriglyceridaemic donkeys

Hyperinsulinaemia is a commonly-observed characteristic of insulin resistance, and a reduction in insulin sensitivity is thought to be either a causative and/or symptomatic feature of equine hyperlipaemia. A positive correlation (r=0·545, P=0·0015) existed between plasma insulin and triglyceride concentrations determined in 31 donkeys with naturally occurring hyperlipidaemia/hyperlipaemia. Greater insulin values tended to occur in the animals with an overweight body score. Inter-animal variation in insulin concentrations, however, prevented the identification of any differences either within hypertriglyceridaemic donkeys (when classified by clinical condition, date of arrival to a sanctuary and eventual outcome after treatment) or between groups of normotriglyceridaemic (n=6) and experimentally fasted hypertriglyceridaemic (n=5) donkeys. Determination of basal plasma insulin concentrations may not provide an accurate assessment of underlying insulin sensitivity. Alternatively, hyperinsulinaemia may be evident only in animals with established insulin resistance.