992 resultados para Admiralty Inlet, Baffin Island, Canada
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Several methods for estimating the potential impacts caused by multiple probabilistic risks have been suggested. These existing methods mostly rely on the weight sum algorithm to address the need for integrated risk assessment. This paper develops a nonlinear model to perform such an assessment. The joint probability algorithm has been applied to the model development. An application of the developed model in South five-island of Changdao National Nature Reserve, China, combining remote sensing data and a GIS technique, provides a reasonable risk assessment. Based on the case study, we discuss the feasibility of the model. We propose that the model has the potential for use in identifying the regional primary stressor, investigating the most vulnerable habitat, and assessing the integrated impact of multiple stressors. (C) 2006 Elsevier Ltd. All rights reserved.
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Chang-Fu Wang, Xian-Qiu Ren, and Run-Lin Xu (2010) Composition, abundance, and diversity of the Peracarida on different vegetation types in the Qi'ao-Dan'gan Island Mangrove Nature Reserve on Qi'ao Island in the Pearl River estuary, China. Zoological Studies 49(5): 608-615. Almost nothing is known about the Peracarida in the Pearl River estuary. This is the 1st report to study the composition, abundance, and diversity of the Peracarida in the Qi'ao-Dan'gan I. Mangrove Nature Reserve on Qi'ao I., in the Pearl River estuary, southern China. Bimonthly samplings were carried out in 3 representative vegetation types (mangrove arbor, emergent plants, and seaweed) for 2 yr. Using a Peterson grab, 1940 individuals (id.) were collected in total, including 11 species of 6 genera, 5 families, and 3 orders (Amphipoda, Isopoda, and Tanaidacean). Discapseudes mackiei Bamber 1997 was the dominant species with the highest density of 1,432 incl./m(2). The effect of temperature on the abundance of Peracarida was significant (p < 0.01), and the optimum temperature was 22-23 degrees C in both the mangrove arbor and seaweed. The results showed that the abundance of the Peracarida was higher in the mangrove arbor, while the diversity, especially Amphipoda diversity, was higher in the seaweed. In contrast, emergent plants provided no suitable habitats for the Peracarida. http://zoolstud.sinica.edu.tw/Journals/49.5/608.pdf
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Hydrothermal fluid containing abundant matter erupts from seafloor, meets ambient cold seawater and forms chimneys. So the main matter origins of chimneys are seawater and matter which are taken by hydrothermal fluid from deep reservoir. However, because of seawater's little contribution to the forming of chimneys, it is usually covered by the abundant matter which is taken by hydrothermal fluid. Therefore, chimneys formed in ordinary deep seawater hydrothermal activity, containing complex elements, cannot be used to study the seawater's contribution to their formation. While the native sulfur chimneys, formed by hydrothermal activity near the sea area off Kueishantao, are single sulfur composition (over 99%), and within chimneys distinct layers are seen. Different layers were sampled for trace element determination, with Inductively Coupled Plasma Mass Spectrometry (ICP-MS). By analyzing the data, we consider C-layer (secondary inner-layer) as the framework layer of the chimney which formed early (Fig. 4), and its trace elements derive from hydrothermal fluid. While the trace elements within A, B, D layers have undergone later alteration. A, B layers are affected by seawater and D layer by hydrothermal fluid. The increase of trace elements of A and B layers was calculated using C layer as background. Based on the known typical volume of chimneys of the near sea area off Kueishantao, we calculated the volume of seawater that contributed trace element to chimneys formation to be about 6.37 x 10(4) L. This simple quantified estimate may help us better understand the seafloor hydrothermal activity and chimneys.
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The species and characteristics of Radiolaria in the surface sediments were systematcally investigated in the sea east of Taiwan Island. One hundred and seventy-eight species of Radiolaria (including 21 unidentified species) have been identified in the surface sediments, and they belong to 2 orders, 34 families and 101 genera. Among them there are 19 families, 70 genera, 134 species of Spumellaria and 15 families, 31 genera, 44 species of Nassellaria. Of the 178 species of Radiolaria, the individual number of Spumellaria amounts to 88.1% of the total individual number, and that of Nassellaria amounts to 11.9% of the total individual number. It is shown that most of the dominant species belong to the tropical and subtropical dominant species and are brought into the area mainly by the Kuroshio, and some affecting factors including the submarine topography, submarine sediments, upwelling current east of Taiwan Island and carbonate dissolution play a secondary role in forming the Radiolaria distributions.
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Elemental (TOC, TN, C/N) and stable carbon isotopic (delta(13)C) compositions and n-alkane (nC(16-38)) concentrations were measured for Spartina alterniflora, a C-4 marsh grass, Typha latifolia, a C-3 marsh grass, and three sediment cores collected from middle and upper estuarine sites from the Plum Island salt marshes. Our results indicated that the organic matter preserved in the sediments was highly affected by the marsh plants that dominated the sampling sites. delta(13)C values of organic matter preserved in the upper fresh water site sediment were more negative (-23.0+/-0.3) as affected by the C-3 plants than the values of organic matter preserved in the sediments of middle (-18.9+/-0.8) and mud flat sites (-19.4+/-0.1) as influenced mainly by the C4 marsh plants. The distribution of n-alkanes measured in all sediments showed similar patterns as those determined in the marsh grasses S. alterniflora and T. latifolia, and nC(21) to nC(33) long-chain n-alkanes were the major compounds determined in all sediment samples. The strong odd-to-even carbon numbered n-alkane predominance was found in all three sediments and nC(29) was the most abundant homologue in all samples measured. Both delta(13)C compositions of organic matter and n-alkane distributions in these sediments indicate that the marsh plants could contribute significant amount of organic matter preserved in Plum Island salt marsh sediments. This suggests that salt marshes play an important role in the cycling of nutrients and organic carbon in the estuary and adjacent coastal waters. (C) 2003 Elsevier Ltd. All rights reserved.
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The present paper reports six genera nine species of Palaemonidae collected from Clipperton Island, eastern tropical Pacific, including three new species of the pontoniine genus Chacella: C. bicornuta, C. quadricornuta, and C. sexicornuta. We provide a key to identify all the six known species of Chacella.
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Gold deposits hosted in the Gezhen shear zone at Qingxi, Hainan Island occur in the Precambrian metamorphic rock series and are regionally developed in the N-E direction along the tectonic zone. From northeast to southwest are distributed the Tuwaishan-Baoban gold mining district, the Erjia gold mining district and the Bumo gold mining district, making up the most industrially important gold metallogenesis zone on the Hainan Island. Isotope geochemical studies of the typical gold deposits in this metallogen
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http://www.archive.org/details/worldwideevangel00unknuoft
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http://www.archive.org/details/fortyyearsamongt00craiuoft
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http://www.archive.org/details/canadasmission00unknuoft/
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The aim of this study was to develop a methodology, based on satellite remote sensing, to estimate the vegetation Start of Season (SOS) across the whole island of Ireland on an annual basis. This growing body of research is known as Land Surface Phenology (LSP) monitoring. The SOS was estimated for each year from a 7-year time series of 10-day composited, 1.2 km reduced resolution MERIS Global Vegetation Index (MGVI) data from 2003 to 2009, using the time series analysis software, TIMESAT. The selection of a 10-day composite period was guided by in-situ observations of leaf unfolding and cloud cover at representative point locations on the island. The MGVI time series was smoothed and the SOS metric extracted at a point corresponding to 20% of the seasonal MGVI amplitude. The SOS metric was extracted on a per pixel basis and gridded for national scale coverage. There were consistent spatial patterns in the SOS grids which were replicated on an annual basis and were qualitatively linked to variation in landcover. Analysis revealed that three statistically separable groups of CORINE Land Cover (CLC) classes could be derived from differences in the SOS, namely agricultural and forest land cover types, peat bogs, and natural and semi-natural vegetation types. These groups demonstrated that managed vegetation, e.g. pastures has a significantly earlier SOS than in unmanaged vegetation e.g. natural grasslands. There was also interannual spatio-temporal variability in the SOS. Such variability was highlighted in a series of anomaly grids showing variation from the 7-year mean SOS. An initial climate analysis indicated that an anomalously cold winter and spring in 2005/2006, linked to a negative North Atlantic Oscillation index value, delayed the 2006 SOS countrywide, while in other years the SOS anomalies showed more complex variation. A correlation study using air temperature as a climate variable revealed the spatial complexity of the air temperature-SOS relationship across the Republic of Ireland as the timing of maximum correlation varied from November to April depending on location. The SOS was found to occur earlier due to warmer winters in the Southeast while it was later with warmer winters in the Northwest. The inverse pattern emerged in the spatial patterns of the spring correlates. This contrasting pattern would appear to be linked to vegetation management as arable cropping is typically practiced in the southeast while there is mixed agriculture and mostly pastures to the west. Therefore, land use as well as air temperature appears to be an important determinant of national scale patterns in the SOS. The TIMESAT tool formed a crucial component of the estimation of SOS across the country in all seven years as it minimised the negative impact of noise and data dropouts in the MGVI time series by applying a smoothing algorithm. The extracted SOS metric was sensitive to temporal and spatial variation in land surface vegetation seasonality while the spatial patterns in the gridded SOS estimates aligned with those in landcover type. The methodology can be extended for a longer time series of FAPAR as MERIS will be replaced by the ESA Sentinel mission in 2013, while the availability of full resolution (300m) MERIS FAPAR and equivalent sensor products holds the possibility of monitoring finer scale seasonality variation. This study has shown the utility of the SOS metric as an indicator of spatiotemporal variability in vegetation phenology, as well as a correlate of other environmental variables such as air temperature. However, the satellite-based method is not seen as a replacement of ground-based observations, but rather as a complementary approach to studying vegetation phenology at the national scale. In future, the method can be extended to extract other metrics of the seasonal cycle in order to gain a more comprehensive view of seasonal vegetation development.
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This article aims to investigate contemporary cultural representations of the Beothuk Indians in art, literature and museum displays in Newfoundland, Canada, focussing on ways these reimagine the past for the present, offering perspectives on contested histories, such as the circumstances leading to the demise of the Beothuk. Wiped out through the impact of colonialism, the Beothuk are the ‘absent other’ who continue to be remembered and made present through the creative arts, largely at the expense of other indigenous groups on the island. Rather than focussing on the ‘non-absent past, according to Polish scholar Ewa Domańska, ‘instead we turn to a past that is somehow still present, that will not go away or, rather, that of which we cannot rid ourselves’ (2006, 346). Depictions of the last Beothuk are part of a cultural remembering where guilt and reconciliation are played out through media of the imagination