Conservation cornerstones: Capitalising on the endeavours of long-term monitoring projects     

Greg J. Holland  Jerry S.A. Alexander  Peter Johnson  Andrew H. Arnold  Merril Halley  Andrew F. Bennett 《Biological conservation》2012,145(1):95-101

Ecological monitoring is widely used to measure change through time in ecosystems. The current extinction crisis has resulted in a wealth of monitoring programs focussed on tracking the status of threatened species, and the perceived importance of monitoring has seen it become the cornerstone of many biodiversity conservation programs. However, many monitoring programs fail to produce useful outcomes due to inherent flaws. Here we use a monitoring program from south-eastern Australia as a case study to illustrate the potential of such endeavours. The threatened carnivorous marsupial, the brush-tailed phascogale (Phascogale tapoatafa), has been monitored at various locations between 2000 and 2010. We present strong evidence for a decline in relative abundance during this period, and also describe relationships with environmental variables. These results provide insights likely to be valuable in guiding future management of the species. In the absence of the monitoring program, informed management would not be possible. While early detection of population declines is important, knowledge of the processes driving such declines is required for effective intervention. We argue that monitoring programs will be most effective as a tool for enhanced conservation management if they test specific hypotheses relating to changes in population trajectories. Greater emphasis should be placed on rigorous statistical analysis of monitoring datasets in order to capitalise on the resources devoted to monitoring activities. Many datasets are likely to exist for which careful analysis of results would have benefits for determining management directions.  相似文献   

Clinical trial of vinblastine in dogs with transitional cell carcinoma of the urinary bladder     

Arnold EJ  Childress MO  Fourez LM  Tan KM  Stewart JC  Bonney PL  Knapp DW 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2011,25(6):1385-1390

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The versatile,changing, and advancing roles of fish in sediment toxicity assessment—a review     

Arnold V. Hallare  Thomas-Benjamin Seiler  Henner Hollert 《Journal of Soils and Sediments》2011,11(1):141-173

Purpose  

Sediments serve as integral and dynamic parts of our aquatic systems. Within the last 15 to 20 years, however, the scientific community has begun noticing deterioration of sediment quality at an alarming rate worldwide. Sediments are now harboring hazardous pollutants that can directly influence water quality, thereby creating very stressful conditions for aquatic life. As a consequence, global efforts were initiated in the early 1970s, to find ways to assess sediment quality. Because of their obvious ecological and economic significance, fish have remained a major taxonomic group for appraising the general quality of aquatic systems. However, for sediment risk assessment, fish have lagged behind invertebrates due to their mobility and generally, pelagic lifestyle. To our knowledge, this is the first paper that comprehensively presents and reviews the versatile role of fish in assessing the state of health of aquatic sediments.  相似文献   

Mineral nutrient and amino acid composition of certain tropical cultivars of soybean     

N.N. Barthakur  N.P. Arnold  D.C. Cloutier  R. Saikia 《Journal of plant nutrition》2013,36(5):599-610

Mineral nutrient and amino acid composition of twelve varieties of soybean grown in an alluvial soil under tropical climate of Assam, India, were studied. On a dry weight basis, Ca and K contents were between 0.35 to 0.46% and 1.66 to 2.11%, respectively, which were relatively high compared with those in temperate varieties. Protein content of the soybeans varied between 40 to 48%. SL‐96 showed the highest amounts of K, Zn, Mn, and B; DS‐37 contained the maximum total amino acids and protein. On the basis of nutrient contents, SL‐96 and DS‐37 are recommended for cultivation in Assam.  相似文献   

Der einfluss von grundwasser und witterung auf den trockenmasseertrag eines grasmischbestandes (lysimeterergebnis)     

Gerhart Mundel  Herbert Arnold 《Archives of Agronomy and Soil Science》2013,59(5):329-348

In einem Langzeitversuch von 18 Jahren wurde in einer Lysimeterserie mit unterschiedlichen Grundwasserständen die Ertragsleistung von Grasmischbeständen untersucht. In einer multiplen linearen Regressionsanalyse konnte ermittelt werden, daß Grundwassertiefe, Niederschlag, Zusatzwasserangebot, Globalstrahlung, Lufttemperatur und das Sättigungsdefizit Einfluß auf den Ertrag haben. Die Zunahme der Globalstrahlung, des Niederschlages und des Zusatzwassers führen zur Ertragserhöhung. Negativ auf den Ertrag wirken sich zunehmende Grundwassertiefe und Lufttemperatur sowie zunehmendes Sättigungsdefizit aus. Es wurde ein Vergleich zwischen gemessenen und errechneten Erträgen vorgenommen, wobei teils sehr gute Übereinstimmungen vorliegen, in einzelnen Jahren auch größere Abweichungen festzustellen sind.  相似文献   

THE EFFECT OF PHYSIOLOGICAL STATUS ON DIET SELECTION BY GRAZING EWES     

W. R. McManus  G. W. Arnold  Judith Ball 《Grass and Forage Science》1968,23(3):223-227

The effect of the physiological status of grazing ewes on diet selection was studied, using ewes with oesophageal fistulae. The diets of dry ewes grazing Phalaris annual grasses and subterranean clover pastures, over a range of availabilities, were compared with those of ewes in various stages of pregnancy and lactation. There were no significant differences at any stage of reproduction in the botanical composition of the diets. However, small differences in diet digestibility, soluble carbohydrate and nitrogen content were found during pregnancy and lactation. These occurred at all levels of availability of pasture. The differences did not appear to have nutritional significance in the particular pasture ecosystems studied because levels of N, soluble carbohydrates and digestibility of the diet were such that selection for survival was unlikely to be necessary.
It is concluded that dry fistulated ewes can be used to obtain samples for assessing diet N and soluble carbohydrate contents for ewes in other physiological states. The use of in vitro digestibility tests of diets of dry ewes to assess diet digestibility for ewes in other physiological states may be subject to error.  相似文献   

Identifying resistance in wild and ornamental cherry towards bacterial canker caused by Pseudomonas syringae     

Michelle T. Hulin  Andrea Vadillo Dieguez  Francesca Cossu  Samantha Lynn  Karen Russell  Helen C. Neale  Robert W. Jackson  Dawn L. Arnold  John W. Mansfield  Richard J. Harrison 《Plant pathology》2022,71(4):949-965

Bacterial canker is a major disease of stone fruits and is a critical limiting factor to sweet cherry (Prunus avium) production worldwide. One important strategy for disease control is the development of resistant varieties. Partial varietal resistance in sweet cherry is discernible using shoot or whole tree inoculations; however, these quantitative differences in resistance are not evident in detached leaf assays. To identify novel sources of resistance to canker, we used a rapid leaf pathogenicity test to screen a range of wild cherry, ornamental Prunus species and sweet cherry × ornamental cherry hybrids with the canker pathogens, Pseudomonas syringae pvs syringae, morsprunorum races 1 and 2, and avii. Several Prunus accessions exhibited limited symptom development following inoculation with each of the pathogens, and this resistance extended to 16 P. syringae strains pathogenic on sweet cherry and plum. Resistance was associated with reduced bacterial multiplication after inoculation, a phenotype similar to that of commercial sweet cherry towards nonhost strains of P. syringae. Progeny resulting from a cross of a resistant ornamental species Prunus incisa with susceptible sweet cherry (P. avium) exhibited resistance indicating it is an inherited trait. Identification of accessions with resistance to the major bacterial canker pathogens is the first step towards characterizing the underlying genetic mechanisms of resistance and introducing these traits into commercial germplasm.  相似文献   

Channel catfish, Ictalurus punctatus, leukocytes secrete immunoreactive adrenal corticotropin hormone (ACTH)     

R.E. Arnold  C.D. Rice 《Fish physiology and biochemistry》2000,22(4):303-310

The interrelationships between the neuroendocrine and immune systems are becoming more understood, at least in mammalian systems. The most characterized of these relationships is that of hormonal signaling within the hypothalamo-pituitary-adrenal (HPA) axis. CNS-perceived signals stimulate the release of corticotropin releasing hormone (CRH) which in turn stimulates the release of pituitary corticotropin (ACTH) and ultimately the release of adrenal-cortex-derived corticosteroids. We demonstrate that channel catfish peripheral blood mononuclear cells, a channel catfish B-cell line (1G8) and a T-cell line (28S.1), constitutively and in response to CRF, secrete a molecule that is reactive with a mammalian RIA for ACTH (irACTH). The T-cell line was the most responsive to CRH and may provide a valuable model for understanding the interrelationships between the neuroendocrine and immune systems in lower vertebrates. Lymphoid derived ACTH, or ACTH-like products, in fish, as well as higher vertebrates, may represent a paracrine or autocrine control on lymphocyte function and immune regulation.  相似文献   

Determination of hematology and plasma chemistry reference intervals for 3 populations of captive Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus)     

Mark A. Matsche  Jill Arnold  Erin Jenkins  Howard Townsend  Kevin Rosemary 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2014,43(3):387-396

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Embryo-Maternal Communication in Bovine – Strategies for Deciphering a Complex Cross-Talk     

E Wolf  GJ Arnold  S Bauersachs  HM Beier  H Blum  R Einspanier  T Fröhlich  A Herrler  S Hiendleder  S Kölle  K Prelle  H-D Reichenbach  M Stojkovic  H Wenigerkind  F Sinowatz 《Reproduction in domestic animals》2003,38(4):276-289

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