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Wild rodents were collected using live snap traps in pistachio gardens of Kerman Province, Southeast Iran from 2007 to 2009, then some physiological parameters of them were measured. The samples were identified as follow: Nesokia indica, Meriones persicus, Meriones lybicus and Tatera indica. Blood samples were obtained from the heart, then the blood parameters (glucose, cholesterol, triglyceride, total protein, HDL, red and white blood cell number) in wild species of rodents and laboratory rat were compared. The results showed that there were no significant differences in serum glucose, triglyceride, HDL and total protein levels among different experimental groups. The concentration of cholesterol in T. indica was more than that in N. indica (P < 0.01). The total numbers of red blood cells also showed significant difference between wild garden rodent species and laboratory rat (P < 0.01), while the numbers of white blood cells showed no significant difference.  相似文献   
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An inventory of the vascular plants, bryophytes, fungi and terricolous lichens recorded within the different sand-dune communities in Wales has been compiled and a summary of the importance of these different taxonomic groups to the ecology and conservation of sand dunes is provided. The total floristic assemblage amounted to 945 species, with vascular plants representing 439 of these. Fungi unexpectedly formed the next most important group with ca. 289 species, followed by bryophytes (171 species) and terricolous lichens (66 species). However, very few of these species are confined to sand dunes. Of the vascular plants only ca. 7 % (32 species) could be classed as either wholly dependent or strongly associated with sand dunes, whereas up to 13% (22 species) of the bryophytes fell within this category. Of the fungi only 4% (10 species) appear to be restricted to sand dunes, but none of the lichen species could be classed as being either limited to, or strongly associated with, this habitat. Over 9% (91 species) of the total flora are considered to be rare, scarce or endangered within the UK or Europe, and ca. 8% of the vascular plant species are considered to be endemic or near-endemic to Europe. The inventory therefore not only provides an insight in the overall plant diversity of dune systems in Wales, it also gives an indication of the proportion of species that are under threat, and the numbers of species that are more-or-less totally dependent on sand dunes. In the discussion various relevant sand-dune management issues are addressed.  相似文献   
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Over-stabilisation and eutrophication affect many dune systems in north-west Europe. This leads to lower diversity of typical dune species and an accumulation of soil nutrients. Existing management techniques to remove excess nutrients include mowing, with removal of cuttings, and turf stripping. A new restoration technique called topsoil inversion or deep ploughing may also be able to counter some of the negative effects of eutrophication. It simulates the burial of established soils with fresh mineral sand, by inverting the soil profile. A trial was carried out on two small blocks of eutrophic dune grassland in North Wales, UK. Nutrient-rich surface soils were buried beneath mineral sub-sand using a double-bladed plough, designed to plough to depths of up to 100 cm. Results show that the organic soil horizons were buried to a depth of 80 cm, and covered with 40–50 cm of mineral sand. The pH and organic matter of the surface layers became comparable to those of mobile dunes. Fifteen months after ploughing, bare sand cover was still 70–90%, but significant sand loss through wind erosion resulted in a thinning of the mineral sand over-burden, leaving the buried organic layer closer to the surface. Natural vegetation colonisation was slow, with the first surviving plants observed after 8 months. The majority of species present at 15 months were present before ploughing and had regenerated from rhizomes or root fragments. The effect of excluding disturbance caused by rabbits, people and dogs was assessed within fenced areas. After 11 months, vegetation cover was greater in the fenced areas than in plots exposed to disturbance, therefore disturbance replaced physical conditions as the dominant influence on plant growth and establishment. These early results suggest the trial has been partially successful, but that topsoil inversion could be combined with other methods such as turf stripping or by stabilisation of the ploughed surface by planting with pioneer species, depending on the ultimate restoration goal.  相似文献   
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Muscle tissue was collected from ewes and lambs derived from farms throughout Scotland and sample concentrations of five endocrine disrupting compound groups were determined. Farms of origin were categorised according to geographic region. There were few statistically-significant differences with region or distance from cities. However, the magnitude of the difference between the highest and lowest mean values in ewe muscle from different regions exceeded 30% for 13 of the 15 compounds that were consistently detected in muscle, with animals derived from the industrialised region having the highest mean values for 11 of the 13 compounds. A less marked trend was apparent in the lamb muscle (8 of 13 highest were in the industrialised region). The physiological effects of such small differences in exposure to mixtures of pollutants remain to be determined.  相似文献   
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Soil concentrations of dioctyl phthalate (DOP) and the alkyl phenols, octyl phenol (OP) and nonyl phenol (NP), after repeated surface applications of sewage sludge to pastures, were investigated. Liquid sludge was applied at a rate of 2.25 tonnes dry matter (DM) per hectare to each of three treated (T) plots on three occasions during the summer and two occasions in the early spring over a period of 2.5 years. Control (C) plots were treated with inorganic fertiliser containing amounts of nitrogen equivalent to those applied to the treated plots. At between 69 and 81 days after the application of sludge, 15 separate soil samples were collected from one half of each of the plots (Experiment 1). Concentrations (microg g(-1)) of DOP were higher (P < 0.001) than those of NP, while those of OP were generally below detectable levels. Mean soil concentrations of DOP were not significantly different in T and C plots [0.233 vs. 0.155 microg g(-1); standard error of the difference (SED) = 0.046; not significant (NS)], partly because there was already a relatively large amount of DOP present. NP concentrations were, however, significantly higher in T than in C plots (0.021 vs. 0.013 microg g(-1) SED = 0.002; P < 0.05). There was no consistent change over time in the mean soil concentrations of these compounds when sampled at intervals of 3-6 months. Concentrations in soil samples collected at monthly intervals following sludge application indicated that the variation in concentrations of these endocrine-disrupting compounds (EDC) was unrelated to time since sludge application. Rates of soil ingestion, expressed as the percentage of DM intake represented by soil, were higher during the winter than the summer (5.40 vs. 1.17; SED = 0.360; P < 0.001) and estimated daily intakes of DOP and NP were up to 150 microg and 8 microg, respectively. It is concluded that the application of sewage sludge to pasture does not increase soil concentrations of phthalate (as DOP) or alkyl phenols. Thus, the risk of increased exposure to these EDC as a result of sludge application is small. However, the small effect of sludge application on soil concentrations may be largely a reflection of the relatively high concentrations of DOP already present in the soil, which may be biologically significant.  相似文献   
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Newborough Warren is a large calcareous west coast UK dune system, which has experienced rapid vegetation spread in the last 70 years. Information from two high resolution chronosequences for dry and wet dune habitats, 0–145 years, was used to answer the following questions: Does climate influence colonisation of vegetation on bare sand? What are the timescales and sequences of successional change in the vegetation? Analysis of aerial photographs showed that stabilisation of the dune system since 1945 has occurred in three main phases. The onset of stabilisation predated myxomatosis by 10 years; while stabilisation virtually halted during the period 1964–1978. Periods of rapid stabilisation were coincident with higher values of Talbot’s Mobility index (M)?>?0.3. Successional development was apparent in both dry and wet habitats. Fixed dune grassland started to replace earlier successional communities at around 40 years, and could persist to 145 years. Linear succession in dune slacks was less apparent, but a separation between communities typically regarded as ‘younger’ and ‘older’ occurred at around 40 years. Species richness in dry dune habitats increased with age to a maximum on soils around 60 years old, then declined again. Species richness was unrelated to age or soil development in wet dune slacks. The influence of climate suggests that conservation managers can only operate within the constraints imposed by natural climatic conditions. Vegetation growth and soil development are closely linked and maintaining some open areas is key to preventing soil development and over-stabilisation.  相似文献   
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Kenfig NNR (National Nature Reserve) is a coastal sand dune system in south Wales, UK. The site is an important location for the conservation of the fen orchidLiparis loeselii, a significant proportion of the UK population is found solely on the site. Approaches to the mapping and monitoring of the habitats at Kenfig NNR using EO (Earth Observation) methods are investigated. Typical airborne EO missions over such sites produce more than a single source of EO data; these may include various optical imaging sensors with different spectral ranges, film cameras and ranging devices to measure topography. Conservation managers are thus presented with the problem of which sources of data to use when producing a land cover map of the site of interest. Using a data set gathered over the Kenfig NNR site, we investigate land cover mapping methods for conservation. The land cover types of interest typically cover small areas within a much larger site so they present a hard problem for the EO data and associated classification methods to solve. Land cover classifications produced from the data sets provide a set of competing hypotheses of land cover type for the site. Methods we use to resolve this competition between the data sets include voting methods, data fusion methods and a method utilising fuzzy logic to aggregate information. This paper is intended to act as an introduction to some of the issues involved in using EO data for habitat mapping in highly heterogeneous coastal dune environments and to present some preliminary results of the performance of each method.  相似文献   
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The Countryside Council for Wales (CCW) is developing a management framework with the primary aim of restoring favourable conservation status to the sand dune resource of Wales. It will take onboard the requirements of both national and international conservation legislation and will also help CCW integrate its responsibilities for biodiversity, geodiversity, landscape, access and recreation for this habitat. In order to achieve certain conservation goals it will be necessary to have in place a variety of different types of management ranging from non- or minimal intervention through to intensive single species management and habitat re-creation. However, it will not provide a comprehensive framework for all aspects of site management, but only those that are deemed to be of strategic importance, and have significance within an all-Wales perspective for their nature conservation importance.  相似文献   
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A generalized quantitative risk assessment for the use of source-segregated green waste (SSGW) compost use in livestock production is presented. This assessment focussed on potential risks associated with a specific product, PAS100 compost that meets the UK publicly available specification 100 and represents the majority of compost available for use in extensive Scottish livestock systems. A hazard screening approach was used to identify all potentially hazardous agents present in compost. A total of 497 potentially hazardous agents were screened, with 147 finally put forward for quantitative risk assessment. Scenarios modelled in the assessment included surface application of compost to grazing land and also incorporation into soil and subsequent uptake by fodder crops. Risk estimates were compared to those associated with six comparator materials, including various sludges, slurries and farm yard manures. Overall, five potentially hazardous agents (PCB28, PCB138, PCB153, 1,2,3,4,6,7,8-HpCDD, Clopyralid) returned a hazard quotient >1 but within margins of uncertainty, indicating that further investigation may be required. Within the limitations of available information, SSGW compost was found to pose less risk to grazing livestock, or the environment, than other commonly-used soil amendments. While this assessment relates to a specific product/standard used in the UK, the methodology could easily be applied to other composts/products/situations. Therefore these results have wider applicability.  相似文献   
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