The 10 Australian ecosystems most vulnerable to tipping points   总被引：2，自引：0，他引：2  

William F. Laurance  Bernard Dell  Stephen M. Turton  Michael J. Lawes  Lindsay B. Hutley  Hamish McCallum  Patricia Dale  Michael Bird  Giles Hardy  Gavin Prideaux  Ben Gawne  Clive R. McMahon  Richard Yu  Jean-Marc Hero  Lin Schwarzkopf  Andrew Krockenberger  Michael Douglas  Ewen Silvester  Michael Mahony  Karen Vella  Udoy Saikia  Carl-Henrik Wahren  Zhihong Xu  Bradley Smith  Chris Cocklin 《Biological conservation》2011,(5):1472-1480

We identify the 10 major terrestrial and marine ecosystems in Australia most vulnerable to tipping points, in which modest environmental changes can cause disproportionately large changes in ecosystem properties. To accomplish this we independently surveyed the coauthors of this paper to produce a list of candidate ecosystems, and then refined this list during a 2-day workshop. The list includes (1) elevationally restricted mountain ecosystems, (2) tropical savannas, (3) coastal floodplains and wetlands, (4) coral reefs, (5) drier rainforests, (6) wetlands and floodplains in the Murray-Darling Basin, (7) the Mediterranean ecosystems of southwestern Australia, (8) offshore islands, (9) temperate eucalypt forests, and (10) salt marshes and mangroves. Some of these ecosystems are vulnerable to widespread phase-changes that could fundamentally alter ecosystem properties such as habitat structure, species composition, fire regimes, or carbon storage. Others appear susceptible to major changes across only part of their geographic range, whereas yet others are susceptible to a large-scale decline of key biotic components, such as small mammals or stream-dwelling amphibians. For each ecosystem we consider the intrinsic features and external drivers that render it susceptible to tipping points, and identify subtypes of the ecosystem that we deem to be especially vulnerable.  相似文献   

Corrigendum to “Modelling forest carbon balances considering tree mortality and removal” [Agric. For. Meteorol. 151 (2011) 179-190]     

Rüdiger Grote  Ralf KieseThomas Grünwald  Jean-Marc OurcivalAndré Granier 《Agricultural and Forest Meteorology》2011,151(5):644

  相似文献   

Modelling forest carbon balances considering tree mortality and removal     

Rüdiger Grote  Ralf KieseThomas Grünwald  Jean-Marc OurcivalAndré Granier 《Agricultural and Forest Meteorology》2011,151(2):179-190

The determination of ecosystem carbon balances is a major issue in environmental research. Forest inventories and - more recently - Eddy covariance measurements have been set up to guide sustainability assessments as well as carbon accounting. A differentiation between ecosystem compartments of carbon such as soil and vegetation, or above- and belowground storages nevertheless requires further empirical assumptions or model simulations. However, models to estimate carbon balances often do not account for carbon export by management and the direct and indirect impacts of forest management. To overcome this obstacle, we complemented a physiologically based process model (MoBiLE-PSIM) with routines for dimensional tree growth and mortality and evaluated the full model with measurements of water availability, primary production, respiration fluxes and forest development (tree dimensions and numbers per hectare).The model is applied to three forests representing different physiological types and climatic environments: Norway spruce, European beech and Mediterranean holm oak. Simulated carbon balances are presented on a daily, annual and decadal time scale throughout the years 1998-2008 for all three stands. On average, gross primary production is 2.0, 1.7, and 1.4 and net ecosystem production 0.6, 0.6, and 0.3 kg C m⁻² a⁻¹. Export of carbon by thinning is highest in the middle-aged beech stand (0.24 kg C m⁻² a⁻¹) which decreases net ecosystem production by 15% compared with an unthinned stand. Between 46 (spruce) and 72 (oak) % of carbon gained by net ecosystem production is sequestered below ground (incl. roots) - a share that is decreased if a part of the carbon is exported as timber. The role of further impacts, in particular carry-over effects in years that follow intense drought periods, is highlighted and the usefulness of the approach for highly resolved environmental change studies is discussed.  相似文献   

Long-distance edge effects in a pine forest with a deep and sparse trunk space: In situ and numerical experiments     

Sylvain Dupont  Jean-Marc BonnefondMark R. Irvine  Eric LamaudYves Brunet 《Agricultural and Forest Meteorology》2011,151(3):328-344

  相似文献   

Surveillance and control of rabies in La Reunion,Mayotte, and Madagascar     

Soa Fy Andriamandimby  Jean-Michel Héraud  Ravo Ramiandrasoa  Maherisoa Ratsitorahina  Jhon H Rasambainarivo  Laurent Dacheux  Anthony Lepelletier  Steven M Goodman  Jean-Marc Reynes  Hervé Bourhy 《Veterinary research》2013,44(1):77

Mayotte and La Reunion islands are currently free of animal rabies and surveillance is performed by the French Human and Veterinary Public Health Services. However, dog rabies is still enzootic in Madagascar with 4 to 10 confirmed human cases each year. The number of antirabies medical centres in Madagascar is still scarce to provide easy access to the local population for post-exposure rabies prophylaxis. Furthermore, stray dog populations are considerable and attempts to control rabies by mass campaigns of dog vaccination have not received sufficient attention from the national health authorities. To address these challenges, an expanded program to control rabies needs to be initiated by the Malagasy authorities.  相似文献   

Validation of an extraction method on whole pericarp of grape berry (Vitis vinifera L. cv. Shiraz) to study biochemical and molecular aspects of flavan-3-ol synthesis during berry development     

Verries C  Guiraud JL  Souquet JM  Vialet S  Terrier N  Ollé D 《Journal of agricultural and food chemistry》2008,56(14):5896-5904

  相似文献   

Effect of pulsed-light treatment on milk proteins and lipids   总被引：1，自引：0，他引：1  

Elmnasser N  Dalgalarrondo M  Orange N  Bakhrouf A  Haertlé T  Federighi M  Chobert JM 《Journal of agricultural and food chemistry》2008,56(6):1984-1991

Pulsed-light treatment offers the food industry a new technology for food preservation. It allows the inactivation of numerous micro-organisms including most infectious foodborne pathogens. In addition to microbial destruction, one can also question whether pulsed-light treatment induced conformational changes in food components. To investigate this question, the influence of pulsed-light treatment on protein components of milk was evaluated by using UV spectroscopy, spectrofluorometry, electrophoresis, and determination of amino acid composition. Pulsed-light treatment resulted in an increase of UV absorbance at 280 nm. The intrinsic tryptophan fluorescence of beta-lactoglobulin (BLG) showed a 7 nm red shift after 10 pulses. SDS-PAGE showed the formation of dimers after treatment of BLG by 5 pulses and more. No significant changes in the amino acid composition of proteins and lipid oxidation were observed after pulsed-light treatment. The obtained results indicated changes in the polarity of the tryptophanyl residue microenvironment of BLG solutions or changes in the tryptophan indole structure and some aggregation of studied proteins. Hence, pulsed-light treatment did not lead to very significant changes in protein components; consequently, it could be applied to process protein foods for their better preservation.  相似文献   

Ethanol effect on the structure of beta-lactoglobulin b and its ligand binding     

Mousavi SH  Chobert JM  Bordbar AK  Haertlé T 《Journal of agricultural and food chemistry》2008,56(18):8680-8684

The changes of structure and ligand binding properties of beta-LG B have been studied by fluorescence and circular dichroism spectroscopy in ethanolic solutions. Fluorescence measurements of retinol/beta-LG interactions at 480 nm in various ethanol concentrations show that the maximal fluorescence intensity induced by this interaction between retinol and beta-LG is observed around 20% v/v of ethanol. It is reduced to zero at 40% and 50% of ethanol. These results suggest that there are two distinct structural changes in beta-LG occurring between 20% and 30% and around 40% of ethanol. The first transition, which increases affinity and the apparent number of binding sites for retinol, may be related or similar to the Tanford transition. The strong quenching of retinol emission at 480 nm in 40% of ethanol indicates the radical transformation of beta-LG tertiary structure and the release of retinol. CD spectra at the aromatic region show that secondary and tertiary structures of beta-LG are not significantly affected between 0% and 20% of ethanol. In 30% of ethanol, beta-sheet percentage of beta-LG decreases with respect to native beta-LG (from 55% to 46%). beta-Sheet percentage in beta-LG increases in 40% and 50% alcohol (51% and 53%) relative to 30% of ethanol, which also indicates the strong rearrangement of the secondary structure of beta-LG, while its tertiary structure and beta-LG interactions are radically changed.  相似文献   

Serotypes of Streptococcus agalactiae cultured from dairy milk samples in Québec          下载免费PDF全文

Daignault D  Guévremont E  Guillemette JM  Messier S  Gottschalk M  Higgins R 《The Canadian veterinary journal. La revue veterinaire canadienne》2003,44(3):217-220

Streptococcus agalactiae remains an important pathogen of dairy herds in Québec, but data about antigenic characteristics of this microorganism are sparse. This study was conducted to determine the variety of S. agalactiae serotypes in dairy herds in Québec. Two hundred and ninety-five isolates cultured from the milk of individual cows from 7 regions of Québec were serotyped. Sixty-two percent of the isolates were untypable. Among the 38% of typeable isolates, serotype III was found most frequently. In conclusion, the heterogeneity found among antigenic determinants of isolates from bovine milk suggests that an immunological method for the detection of S. agalactiae performed directly on bovine milk would not be a practical approach.  相似文献   

Fasciola hepatica and Paramphistomum daubneyi: changes in prevalences of natural infections in cattle and in Lymnaea truncatula from central France over the past 12 years     

Mage C  Bourgne H  Toullieu JM  Rondelaud D  Dreyfuss G 《Veterinary research》2002,33(5):439-447

A retrospective study was carried out over a 10- to 12-year period to analyse the changes in prevalences of natural fasciolosis and paramphistomosis among cattle and snails in central France, and to determine the causes which had induced these changes. The prevalences of natural fasciolosis in cattle increased from 1990 to 1993 (13.6% to 25.2%) and diminished afterwards up to 1999 (at 12.6%). Those of natural paramphistomosis showed a progressive increase between 1990 and 1999 (from 5.2 to 44.7%). The prevalences of natural infections and the numbers of free rediae counted in the snails (Lymnaea truncatula) infected with F. hepatica did not show any significant variations over time. By contrast, the prevalences of natural paramphistomosis in snails significantly increased from 1989 to 1996 and remained afterwards in the same range of values (3.7-5.3%), while the number of free rediae significantly increased up to 2000 (from a mean of 6.5 to 13.8 rediae per infected snail, respectively). Three hypotheses may explain the increase of paramphistomosis in cattle and snails: a better quality of diagnosis for the detection of P. daubneyi eggs in veterinary analysis laboratories, the use of specific molecules in the treatment of cattle fasciolosis since 1993, and the lack of an effective treatment up to now against cattle paramphistomosis. Since the objective of most farmers in central France is to obtain the highest antiparasitic efficiency with a single treatment of cattle per year, it is reasonable to assume that the prevalence of bovine paramphistomosis will continue to increase in the future.  相似文献