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In recent decades the clearing of Mediterranean maquis along with the creation of new pastures has been a major factor of land degradation in Sardinia (Italy). This was due to an inadequate implementation of agricultural policies. Consequently, tillage and water erosion intensified over a wide area. The present work assesses the impacts of land use change on soil properties in a representative area of central-eastern Sardinia. Paired forest and pasture sampling sites were selected in relation to present land use, land suitability, and land use history. Different soil properties were considered: physical (sand, silt, clay, soil thickness, bulk density, and penetration resistance), chemical (pH, OC, N, C/N, Ca, Mg, Na, K, CEC, and BS), biological (BQI), and micromorphological (microporosity and microstructure). The comparison of forest and pasture soils showed a significant soil loss (in terms of soil thickness, −22%), and a clear decrease in organic carbon storage (−64% on average). An increase in bulk density (+ 44%) and a change in microporosity and its vertical distribution were also observed, respectively by field measurements and micromorphological quantification on digital images.  相似文献   
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This report describes a 2.8-year-old Swiss Braunvieh heifer with conjunctival changes as the lead clinical signs of malignant lymphoma. The heifer was referred to our clinic because of conjunctivitis that did not respond to treatment with antibiotics. The patient had bilateral lacrimation, severe swelling of the third eyelids and prolapse of the conjunctivae, which were erythematous and covered with haemorrhagic crusts. A clinical examination revealed enlarged prescapular and prefemoral lymph nodes. Based on cytological examination of a fine needle aspirate from a prescapular lymph node, a tentative diagnosis of malignant lymphoma was made. The heifer was euthanased and a postmortem examination carried out. The conjunctival lesions consisted of diffuse multifocal nodules of varying size. There was generalised lymphadenopathy and beige nodules were seen in several internal organs. Histological and immunohistological examinations confirmed the diagnosis of multicentric leukosis characterised by T-cell lymphoblasts, which had also infiltrated the conjunctivae. Examination of a blood sample for enzootic bovine leukosis virus yielded a negative result.  相似文献   
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Journal of Soils and Sediments - Loess in Northern Italy has been usually considered deposited during the MIS 4-2 period, which corresponds to the last Pleistocene glacial cycle. In particular, no...  相似文献   
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A multidisciplinary approach was followed to study the pedogenic and palaeoclimatic information preserved in a buried palaeosol belonging to a Late Quaternary succession located along the bay of Alghero (north‐western Sardinia). The bay is dominated by a 5‐km long sandy beach‐ridge system backing an N‐S oriented lagoon system (Calich). The succession studied is characterized by basal shallow marine deposits, followed by clayey lagoon sediments and colluvial strata and capped by a relatively thick aeolianite. The research was based on pedological and sedimentological analyses, supported by optically stimulated luminescence (OSL) dating and by an in‐depth micro‐morphological study. Three main climatic pulses were highlighted during the Eemian. A wet period, with intense carbonate leaching occurred at the very beginning of the Eemian interglacial followed by very dry climatic conditions. This dry phase was long and arid enough to allow the formation of a thick calcrete hardpan, a typical feature of semi‐arid environments. The hardpan is dated at about 120 ka (kilo annum) and this dry event is tentatively associated with the late Eemian arid pulse (LEAP). The last phase of the Eemian recorded the restoration of a wetter climate. Finally, the succession indicated that even in a cooler environment, the central Mediterranean most probably maintained temperate conditions at least until the end of the MIS 5c (about 95 ka; early Würm).  相似文献   
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The clearing of Mediterranean maquis along with the creation of new pasture land has been an important factor of soil and land degradation in the Mediterranean region. The present research compared soil aggregates and their intraporosity in paired pasture/maquis plots in central E Sardinia (Italy), to study the impact of land use change on soil structure. Undisturbed surface horizons were sampled for thin‐section analysis. Aggregate shape was compared and intraporosity was studied for representative aggregates at different depths. Furthermore, the interaction of root activity and grazing under pasture and maquis cover was discussed. The outcomes revealed a complex interplay of trampling and root activity effects. A decrease (–44%) in total voids (regular pores), along with higher aggregate regularity, was observed under pasture in the 0–2 cm layer, and an increase (+261%) in 50–100 μm planar (elongated) pores was determined in the 2–4 cm layer, suggesting a possible surface compaction due to trampling and an increased subsurface fine root activity by the grassland vegetation.  相似文献   
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The present study assesses the effects of Atriplex nummularia Lindl. growth on soil chemical properties in a semi-arid area. The area is located in the Marrakech province (Morocco), in a degraded agropastoral region subjected to soil restoration actions based on fodder shrub plantations.  相似文献   
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The clinical, haematological and biochemical findings, treatment and outcome of 63 cows with haemorrhagic bowel syndrome are described. The general condition and demeanor were moderately to severely abnormal in all the cows. Signs of colic occurred in 27 cows, decreased rectal temperature in 46 and tachycardia in 44. With the exception of one cow, intestinal motility was decreased or absent. Transrectal palpation revealed dilatation of the rumen in 47 cows and dilatation of the small intestine in 18. Faecal output was markedly reduced or absent, and the faeces were dark brown to black and contained blood. Nine cows were euthanized immediately after physical examination. Conservative medical therapy was instituted in two cows; however, both were euthanized a few days later because of deterioration in condition. Exploratory right flank laparotomy was carried out in 52 cows. Of these, 22 were euthanized intraoperatively because of severe lesions. In 27 cows, intestinal massage to reduce the size of blood clots was carried out; 11 were euthanized several days postoperatively because of deterioration in condition. In three other cows, intestinal resection was carried out and all survived. Of the 63 cows, 19 (30.2%) survived and were healthy at the time of discharge from the clinic.  相似文献   
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A 10-year-old Swiss Braunvieh cow near term was referred to our clinic because of severe abdominal distension, which caused loss of demarcation between the udder and ventral abdominal wall. Ultrasonographic examination revealed marked ascites and multiple echogenic nodules in the greater omentum. Based on the findings, non-inflammatory ascites attributable to neoplasia was diagnosed. Rupture of the prepubic tendon from the pubic symphysis was also suspected. Because of a grave prognosis, parturition was induced and a live calf was delivered. The cow was euthanized and a postmortem examination was carried out. The abdominal cavity contained 248.5 litres of clear fluid. The greater omentum was thickened and oedematous and regionally contained fluid-filled cystic structures, which varied in size with a maximum diameter of 10 centimetres. Based on the histological, immunohistochemical and electron microscopical findings, biphasic mesothelioma with cyst formation affecting the entire abdominal cavity was diagnosed.  相似文献   
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