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41.
42.
In 2008 two male sperm whales (Physeter macrocephalus) stranded along the northern California coast with large amounts of fishing net scraps, rope, and other plastic debris in their stomachs. One animal had a ruptured stomach, the other was emaciated, and gastric impaction was suspected as the cause of both deaths. There were 134 different types of nets in these two animals, all made of floating material, varying in size from 10 cm2 to about 16 m2. The variability in size and age of the pieces suggests the material was ingested from the surface as debris rather than bitten off from active gear. These strandings demonstrate that ingestion of marine debris can be fatal to large whales, in addition to the well documented entanglements known to impact these species.  相似文献   
43.
Current fire danger scales do not adequately reflect the potential destructive force of a bushfire in Australia and, therefore, do not provide fire prone communities with an adequate warning for the potential loss of human life and property. To determine options for developing a bushfire severity scale based on community impact and whether a link exists between the energy release rate (power) of a fire and community loss, this paper reviewed observations of 79 wildfires (from 1939 to 2009) across Victoria and other southern states of Australia. A methodology for estimating fire power based on fuel loading, fire size and progression rate is presented. McArthur??s existing fire danger indices (FDIs) as well as fuel- and slope-adjusted FDIs were calculated using fire weather data. Analysis of possible relationships between fire power, FDIs, rate of spread and Byram??s fireline intensity and community loss was performed using exposure as a covariate. Preliminary results showed that a stronger relationship exists between community loss and the power of the fire than between loss and FDI, although fuel-adjusted FDI was also a good predictor of loss. The database developed for this study and the relationships established are essential for undertaking future studies that require observations of past fire behaviour and losses and also to form the basis of developing a new severity scale.  相似文献   
44.
The study area is the N’zi watershed, sub-watershed of the Bandama River (Ivory Coast). The N’zi watershed is located between longitudes 3°49′ and 5°22′ West and latitudes 6°00′ and 9°26′ North and covers an area of 35,500 km2. This study aims to identify trends in the rainfall-runoff relationship by using a monthly conceptual model. The methodology has consisted on the one hand in highlighting the existence of interannual climate and hydrological variability by using the method of segmentation of Hubert, and on the other hand, in applying the crossed simulations method by using the GR2M model, over several 7-year sub-periods. The results of the application of the method of segmentation of Hubert have demonstrated the presence of a hydroclimatic variability in the N’zi watershed. The modifications of the climate and physical conditions of the flow resulted in a modification of the hydrological response of the watershed translated by a non-stationarity in the rainfall-runoff relation.  相似文献   
45.
Soils are recipients of contaminants from the burning of metal-containing materials in bonfires. In order to obtain a better understanding of the impacts of bonfires on soils, a total of 218 surface soil samples were collected from a traditional bonfire site in Galway City, Ireland. Concentrations of 14 elements including Al, Ca, Co, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sc, Ti and Zn in 30 selected samples were determined using ICP-OES. Strong variations were observed for these elements. Concentrations of Zn, Cu and Pb were elevated, indicating that these metals may be influenced by human activities. Therefore, concentrations of these three metals were further measured using a portable X-ray fluorescence (P-XRF) analyser (n = 218) and their spatial distribution was investigated using a Geographical Information System (GIS). Soils with elevated metal concentrations, as evident from the spatial distribution maps, coincided with the locations of traditional festival bonfires. The results of this study provide useful information for the management of bonfire sites including the enforcement of a control policy regarding the burning of materials in bonfires.  相似文献   
46.
Using the elimination of the parallax followed by the Delaunay normalization, we present a procedure for calculating a normal form of the main problem (J 2 perturbation only) in satellite theory. This procedure is outlined in such a way that an object-oriented automatic symbolic manipulator based on a hierarchy of algebras can perform this computation. The Hamiltonian after the Delaunay normalization is presented to order six explicitly in closed form, that is, in which there is no expansion in the eccentricity. The corresponding generating function and transformation of coordinates, too lengthy to present here to the same order; the generator is given through order four. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
47.
The modern analogue technique (MAT) was applied to six pollen sequences from the Belledonne Massif (northwestern French Alps) to estimate the effect of altitude and local parameters on pollen‐based climate reconstruction during the Lateglacial and the early Holocene. The six sites (Le Vivier (345 m a.s.l.), Les Etelles (700 m a.s.l.), La Coche (980 m a.s.l.), Montendry (1330 m a.s.l.), Le Grand Leyat (1660 m a.s.l.), La Gouille (1800 m a.s.l.)) are located in different vegetation belts (mixed deciduous woods, conifer woods, alpine pastures with maple). The main vegetation changes in the past are recorded at each site. The evolution of four climate parameters (coldest month temperature, warmest month temperature, mean annual temperature, annual precipitation) was quantitatively inferred from pollen data using MAT. The curves obtained were compared to the Les Etelles site, which was the least affected by non‐local pollen transport. The results show consistent trends for the climate parameters reconstructed at the different sites. However, the reconstruction does not indicate a decrease in temperature values related to the increasing elevation. Difficulties in reconstructing the altitudinal variations of climate parameters from pollen data during the periods studied are discussed and perspectives for improvement are considered. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
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