Spatial patterns in the distribution of tropical tree species   总被引：1，自引：0，他引：1  

Condit R  Ashton PS  Baker P  Bunyavejchewin S  Gunatilleke S  Gunatilleke N  Hubbell SP  Foster RB  Itoh A  LaFrankie JV  Lee HS  Losos E  Manokaran N  Sukumar R  Yamakura T 《Science (New York, N.Y.)》2000,288(5470):1414-1418

Fully mapped tree census plots of large area, 25 to 52 hectares, have now been completed at six different sites in tropical forests, including dry deciduous to wet evergreen forest on two continents. One of the main goals of these plots has been to evaluate spatial patterns in tropical tree populations. Here the degree of aggregation in the distribution of 1768 tree species is examined based on the average density of conspecific trees in circular neighborhoods around each tree. When all individuals larger than 1 centimeter in stem diameter were included, nearly every species was more aggregated than a random distribution. Considering only larger trees (>/= 10 centimeters in diameter), the pattern persisted, with most species being more aggregated than random. Rare species were more aggregated than common species. All six forests were very similar in all the particulars of these results.  相似文献   

Predatory Dinosaurs from the Sahara and Late Cretaceous Faunal Differentiation     

PC Sereno  DB Dutheil  M Iarochene  HCE Larsson  GH Lyon  PM Magwene  CA Sidor  DJ Varricchio  JA Wilson 《Science (New York, N.Y.)》1996,272(5264):986-991

Late Cretaceous (Cenomanian) fossils discovered in the Kem Kem region of Morocco include large predatory dinosaurs that inhabited Africa as it drifted into geographic isolation. One, represented by a skull approximately 1.6 meters in length, is an advanced allosauroid referable to the African genus Carcharodontosaurus. Another, represented by a partial skeleton with slender proportions, is a new basal coelurosaur closely resembling the Egyptian genus Bahariasaurus. Comparisons with Cretaceous theropods from other continents reveal a previously unrecognized global radiation of carcharodontosaurid predators. Substantial geographic differentiation of dinosaurian faunas in response to continental drift appears to have arisen abruptly at the beginning of the Late Cretaceous.  相似文献   

Fenthion poisoning of native birds in southern Queensland     

RA McKENZIE  AEL LANHAM  JD TAYLOR  JA GIBSON  RJ PIERCE 《Australian veterinary journal》1996,74(4):321-323

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The risks and problems associated with the import and export of domestic poultry     

W L Ashton 《The British veterinary journal》1984,140(3):221-228

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Angiostroneylosis in Cornwall: Clinical presentations of eight cases     

M. W. S. Martin  G. Ashton  V. R. Simpson  C. Neal 《The Journal of small animal practice》1993,34(1):20-25

Clinical signs in eight dogs with Angiostrongylus vasorum infection included chronic cough, dyspnoea, lumbar pain, hindleg paresis/paralysis, abdominal pain, weakness and collapse; two of the dogs were asymptomatic. Thrombocytopenia was present in two dogs and a mild anaemia in one. Thoracic radiographs showed mild right heart enlargement in two out of three dogs and a pneumothorax in one. At post mortem examination in three dogs, the lungs were swollen with a mottled appearance and there was dilatation of the right ventricle. Adult A vasorum were found in the right heart, the pulmonary artery and its branches. Adult worms were also found in the systemic vasculature in one dog, associated with thromboembolism. Treatment with ivermectin in two dogs and fenbendazole in three dogs resulted in the resolution of clinical signs and no demonstrable larvae in the faeces one to two weeks later.  相似文献   

Artificial Insemination in Dogs     

JA Rodger 《Australian veterinary journal》1993,70(12):462-463

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Chronic renal failure and urolithiasis in a 2-years-old colt     

JA LAING  AL RAISIS  RJ RAWLINSON  AC SMALL 《Australian veterinary journal》1992,69(8):199-200

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4 THE EFFECTS OF EXERCISE AND INJURY ON CHONDROITIN SULFATE AND KERATAN SULFATE CONTENT IN EQUINE SYNOVIAL FLUID.     

MP  Brown  AHK Plaas  JD Sandy  JA Hernandez  KA Merritt  . 《Veterinary surgery : VS》2003,32(6):599-599

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Antimicrobial susceptibility of Pasteurella multocida isolates from cases of pneumonia in slaughter swine from south-east Queensland     

CP STEPHENS  JA GIBSON  L RICHARDSON 《Australian veterinary journal》1995,72(4):156-156

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Chorioretinitis and buphthalmos in turkeys     

K C Barnett  W L Ashton  G Holford  I Macpherson  P D Simm 《The Veterinary record》1971,88(24):620-627

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