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311.
- 1. Mapping of seabed habitats is increasingly being used to identify the distribution and structure of marine ecosystems and as surrogate measures of biodiversity for marine protected area (MPA) planning. In this study, the distribution of seabed habitats to the 3 nmi limit around the Kent Group of islands, south‐eastern Australia were mapped using video ground‐truthed single‐beam acoustics at the mesoscale level (10 m to 1 km) as part of an MPA planning process.
- 2. Six distinct seabed habitat types (continuous reef, patchy reef, sand, hard sand, sparse sponge, and seagrass) were identified based primarily on visual differences in the first and second echo and a further four (low, medium and high profile reef, and sand hills) on variations in seabed profile identified in the echogram. Extensive acoustic and video transects allowed an estimate of the broad‐scale spatial distribution of seabed habitats defined at several hierarchical levels and provided information on the cover of the dominant benthic species or assemblages.
- 3. The island group supports a range of consolidated habitats, including rocky reefs of varying profile dominated by the macroalgae Phyllospora comosa and Ecklonia radiata in depths down to around 45 m, adjacent to deeper sponge‐dominated reefs containing encrusting, erect and branching forms. Unconsolidated habitats occurred broadly through the island group, with the offshore region dominated by hard sand (sand with scallop shells and/or shell grit) and sparse sponge‐habitats (sand interspersed with low cover of sponge‐dominated assemblages). The sheltered coves were dominated by sand and seagrass habitats consisting of beds of the seagrasses Halophila australis, Zostera tasmanica and Posidonia australis, with variations in species composition, patchiness and percentage cover evident within and between coves.
- 4. In February 2004 the Kent Group MPA was announced, covering all waters out to the 3 nmi limit containing two areas defined as a Sanctuary Zone (‘no take’) and a Habitat Protection Zone (‘restricted take’). Overall, seabed habitat mapping generated a capability to define the boundary and size of potential MPA zones within the Kent Group of islands and was an essential component of the planning process to improve the likelihood that the MPA was comprehensive, adequate and representative (CAR).
- 5. The need to define habitats at multiple scales within a hierarchical classification scheme that are meaningful in terms of biodiversity and CAR principles and identifiable using mapping techniques is discussed.
312.
Dirk Maes Wouter Vanreusel Ilf Jacobs Koen Berwaerts Hans Van Dyck 《Biological conservation》2012,145(1):258-266
Red Lists are used to assess the extinction risk of species based on quantitative IUCN criteria. For the compilation of a new Red List of butterflies in Flanders (north Belgium), we collated ca 800,000 distribution records and applied the IUCN Red List criteria to this small region (ca 135,00 km2). We also explored the effect of spatial resolution on the outcome of the Red List assessment by alternatively using 1 × 1 km2 and 5 × 5 km2 grid cells for geographic range size and trend calculations. We determined conservation hot spots in Flanders based on the Red List status of the species composition in each grid cell. The new Red List classified 20 butterflies (out of 68 resident species) as Regionally Extinct, six as Critically Endangered, five as Endangered, seven as Vulnerable and seven as Near Threatened. The remaining 23 species were classified as Least Concern. Using coarse instead of fine grain grid cells would have classified ten species in a lower Red List category. Compared with the previous Red List, nine species were classified in a lower and 12 in a higher threat category. In total, 218 1 × 1 km2 grid cells were considered as (very) high butterfly conservation priority sites. The application of the new IUCN criteria in a small region such as Flanders resulted in a Red List that offered challenging opportunities for the conservation of butterflies in particular and biodiversity in general. 相似文献
313.
Potential commercial wheat cultivars usually have to adhere to strict criteria regarding primary rheological and baking properties such as mixogram peak time, alveogram dough strength and configuration ratio, farinogram water-absorption and loaf volume. Excluding the mixogram, all these tests require large quantities of flour, which is only available during the advanced breeding phases. The aim of this study was to determine if additional selected mixogram parameters, other than the peak time, can be used as indicators of acceptable rheological and baking characteristics. Thirteen mixogram parameters were used to determine correlations with primary rheological and baking characteristics. Highly significant correlations between mixogram and rheological and baking characteristics were observed. Multiple stepwise regressions indicated variable contributions made by the selected mixogram characteristics to variation in the measured characteristics. Specific mixogram parameters were identified which can be used as indicators of the most important baking and rheological characteristics. 相似文献
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Carter JA Fabrycky DC Ragozzine D Holman MJ Quinn SN Latham DW Buchhave LA Van Cleve J Cochran WD Cote MT Endl M Ford EB Haas MR Jenkins JM Koch DG Li J Lissauer JJ MacQueen PJ Middour CK Orosz JA Rowe JF Steffen JH Welsh WF 《Science (New York, N.Y.)》2011,331(6017):562-565
The Kepler spacecraft has been monitoring the light from 150,000 stars in its primary quest to detect transiting exoplanets. Here, we report on the detection of an eclipsing stellar hierarchical triple, identified in the Kepler photometry. KOI-126 [A, (B, C)], is composed of a low-mass binary [masses M(B) = 0.2413 ± 0.0030 solar mass (M(⊙)), M(C) = 0.2127 ± 0.0026 M(⊙); radii R(B) = 0.2543 ± 0.0014 solar radius (R(⊙)), R(C) = 0.2318 ± 0.0013 R(⊙); orbital period P(1) = 1.76713 ± 0.00019 days] on an eccentric orbit about a third star (mass M(A) = 1.347 ± 0.032 M(⊙); radius R(A) = 2.0254 ± 0.0098 R(⊙); period of orbit around the low-mass binary P(2) = 33.9214 ± 0.0013 days; eccentricity of that orbit e(2) = 0.3043 ± 0.0024). The low-mass pair probe the poorly sampled fully convective stellar domain offering a crucial benchmark for theoretical stellar models. 相似文献
318.
Dr. C. E. Bodwell C. W. Miles E. Morris E. S. Prather W. Mertz J. J. Canary 《Plant foods for human nutrition (Dordrecht, Netherlands)》1987,37(4):361-376
The iron status of men, women and children consuming beef extended with soy protein was evaluated by measuring serum ferritin and clinical parameters of iron status during a six-month study. Fifty-two families (245 participants) were randomly assigned to consume, for 180 days, 1 of 7 beef products: all beef, beef extended with either soy isolate, soy concentrate or soy flour (20% reconstituted soy product, 80% beef), or beef extended with each of the three soy products fortified with 60 mg Fe and 25 mg Zn/100 g protein. The beef product was consumed by the subjects as their principal source of protein for 1 meal a day (children 1–18 yr) or 1–2 meals a day (11 per week; adult men and women). A control group consumed their usual self-selected diets. No evidence was found that consumption of beef extended with soy protein deleteriously affected the iron status of men, women or children. Consumption of beef extended with soy protein, at the levels used in this study, by military men and women and by school lunch participants would not appear to impose a risk in these population groups. 相似文献
319.
Prevalence and patterns of antimicrobial resistance of fecal Escherichia coli among pigs on 47 farrow-to-finish farms with different in-feed medication policies in Ontario and British Columbia 下载免费PDF全文
Holy T. Akwar Cornelis Poppe Jeff Wilson Richard J. Reid-Smith Monica Dyck Josh Waddington Dayue Shang Scott A. McEwen 《Canadian journal of veterinary research》2008,72(2):195-201
The main objectives of this study were to determine the prevalence and patterns of antimicrobial resistance in pigs on farms that medicated swine ration and those that did not. A total of 940 isolates of Escherichia coli from 188 pooled fecal samples obtained from weaner and finisher pigs on 47 farrow-to-finish swine farms (34 farms used in-feed medication and 13 did not) were tested for susceptibility to 21 antimicrobials using a breakpoint concentration method. The prevalence of resistance varied widely (0.0% to 81.3%) among the antimicrobials tested. Ninety percent of all the isolates tested were resistant to one or more antimicrobials. The most common multi-drug resistance patterns were to 2 to 6 antimicrobials. Resistance was significantly more frequent (P < 0.01) on farms that used in-feed medication compared to those that did not, and significantly more frequent (P < 0.01) in weaner pigs compared to finisher pigs. These findings indicate that resistance to a broad range of antimicrobials was prevalent among fecal E. coli isolates of pigs on study farms, and that this constitutes a potential reservoir for resistance genes that could spread to pathogens. The findings also provide further evidence that use of medication in swine rations provides selective pressure for antimicrobial resistance in E. coli in pigs. 相似文献
320.
Effects of pre‐slaughter stressor and feeding preventative Chinese medicinal herbs on glycolysis and oxidative stability in pigs 下载免费PDF全文
Linqi Xie Xiaodong Hu Xi Lin Changzheng Wu Ningcong Zhou Anru Wang Miles Todd See 《Animal Science Journal》2016,87(8):1028-1033
A total of 64 5‐month‐old Pietrain pigs were randomly allocated to four treatments with four replicates per treatment according to body weight. The pigs were fed either a standard corn‐soybean meal based control diet (treatments 1 and 2), the standard diet with 1% Lycium barbarum (LB) (treatment 3), or the standard diet with 1% Polygala tenuifolia Willd (PT) (treatment 4). Serum lactic acid and glucose concentrations were increased in stressed pigs (P < 0.05). Addition of the herbs in the diet had no effect on the serum lactic acid concentration, but 1% LB decreased (P < 0.05) serum glucose concentration in the stressed pigs. Pre‐slaughter stress also decreased (P < 0.01) liver glycogen concentration and the decrease could be inhibited by addition of 1% LB in the diet (P > 0.05). Pre‐slaughter stress increased the concentration of maleic dialdehyde (MDA) (P < 0.05) and decreased glutathione peroxidase (GSH‐Px) activity in serum, while dietary 1% LB increased (P < 0.05) the activity of GSH‐Px and decreased the concentration of MDA in the serum. In conclusion, pre‐slaughter stress induces oxidative stress in pigs and dietary supplementation with 1% LB improves antioxidant capacity in stressed pigs before slaughtering. 相似文献