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1.
Firms often encounter location-based impediments that hinder them from engaging with international markets. These challenges can be exacerbated for smaller firms, which often have limited resources and exposure to global markets. This article examines successful small and medium-sized exporters from Nova Scotia, a province with decreased export activity in recent years. It explores these firms’ trade-related motivations, their impediments, and the strategies that they have used to address possible location-related problems. Although geographical distance does not appear to be a competitive challenge, other issues emerge, including travel expenditures and the costs of export intelligence gathering. Successful exporters have overcome many potential impediments by using government trade programs, establishing and maintaining face-to-face contacts, and working with international partners. 相似文献
2.
The metabolic balance between production and respiration in plankton communities of the Gulf of Papua was investigated in May 2004. Water samples taken at 19 stations were allocated to groups on the basis of physico-chemical characteristics. Oxygen consumption and production in flasks incubated in the dark and in the light was determined by micro-Winkler titration. Dark bottle respiration in samples influenced by the estuarine plume averaged 3.09±1.92 (SD) mmol O2 m−3 d−1 and production within surface light bottles averaged 7.63±3.36 (SD) mmol O2 m−3 d−1. Corresponding values in stations more typical of the central Gulf of Papua were 1.68±1.30 (SD) mmol O2 m−3 d−1 and 1.08±2.25 (SD) mmol O2 m−3 d−1. Despite a shallow (<10 m) euphotic zone within the plume stations, phytoplankton production in the surface layers was sufficiently high to subsidise total water column respiration. Integrating production and respiration over the water column resulted in a calculation of net community production (NCP) of 626±504 (SD) mg C m−2 d−1, and community respiration (CR) of 712±492 mg C m−2 d−1 at the plume stations, with an average P:R ratio of 1.97. In the offshore group NCP was 157±450 (SD) mg C m−2 d−1 and CR was 1620±1576 mg C m−2 d−1. The average P:R ratio was 1.27. Three of the 7 stations allocated to the offshore group were net heterotrophic. In contrast to earlier studies in the area indicating that the Gulf of Papua waters is heterotrophic [Robertson, A.I., Dixon, P., Alongi, D.M., 1998. The influence of fluvial discharge on pelagic production in the Gulf of Papua, Northern Coral Sea. Estuarine, Coastal and Shelf Science 46, 319–331], our data indicate that in May 2004 the Gulf was in positive metabolic balance, but by only ∼120 mg C m−2 d−1. We conclude that waters of the Gulf of Papua under riverine influence are net autotrophic, but that within the central Gulf there is a fine metabolic balance alternating between autotrophy and heterotrophy. 相似文献
3.
Fault-controlled dolomitization at Swan Hills Simonette oil field (Devonian), deep basin west-central Alberta, Canada 总被引：6，自引：0，他引：6
The partly dolomitized Swan Hills Formation (Middle‐Upper Devonian) in the Simonette oil field of west‐central Alberta underwent a complex diagenetic history, which occurred in environments ranging from near surface to deep (>2500 m) burial. Five petrographically and geochemically distinct dolomites that include both cementing and replacive varieties post‐date stylolites in limestones (depths >500 m). These include early planar varieties and later saddle dolomites. Fluid inclusion data from saddle dolomite cements (Th=137–190 °C) suggest that some precipitated at burial temperatures higher than the temperatures indicated by reflectance data (Tpeak=160 °C). Thus, at least some dolomitizing fluids were ‘hydrothermal’. Fluorescence microscopy identified three populations of primary hydrocarbon‐bearing fluid inclusions and confirms that saddle dolomitization overlapped with Upper Cretaceous oil migration. The source of early dolomitizing fluids probably was Devonian or Mississippian seawater that was mixed with a more 87Sr‐rich fluid. Fabric‐destructive and fabric‐preserving dolostones are over 35 m thick in the Swan Hills buildup and basal platform adjacent to faults, thinning to less than 10 cm thick in the buildup between 5 and 8 km away from the faults. This ‘plume‐like’ geometry suggests that early and late dolomitization events were fault controlled. Late diagenetic fluids were, in part, derived from the crystalline basement or Palaeozoic siliciclastic aquifers, based on 87Sr/86Sr values up to 0·7370 from saddle dolomite, calcite and sphalerite cements, and 206Pb/204Pb of 22·86 from galena samples. Flow of dolomitizing and mineralizing fluids occurred during burial greater than 500 m, both vertically along reactivated faults and laterally in the buildup along units that retained primary and/or secondary porosity. 相似文献
4.
I. C. Duggan 《新西兰海洋与淡水研究杂志》2013,47(4):825-829
The thiarid snail Melanoides tuberculata (Müller, 1774), native to the Middle East and East Africa, is recorded from the wild in New Zealand for the first time from a geothermally influenced stream at Golden Springs, near Taupo. Introduction was most likely the result of one or more releases from tropical aquaria, although the timing of release is uncertain. Specimens were collected at temperatures of 29.0 and 30.4°C, and survival at these sites is likely dependent on the elevated stream temperatures. The possible spread of this species to other habitats, and potential effects on native thermal water communities, are discussed. 相似文献
5.
Many transoceanic vessels enter the Great Lakes carrying residual ballast water and sediment that harbours live animals and diapausing eggs. In this study, we examine the potential for sodium hypochlorite (NaOCl) to reduce the risk of species introductions from diapausing invertebrate eggs in residual ballast sediment. We collected sediment from three transoceanic vessels and from Lake Erie and exposed them to NaOCl concentrations between 0 and 10,000 mg/L for 24 h. Hatching success was reduced by >89% in all four experiments at 1,000 mg/L relative to unexposed controls. Fewer species hatched at high than at low NaOCl concentrations. Based on an average residual ballast of 46.8 tonnes, the volume of NaOCl required to treat inbound vessels is 374 L. Impacts of NaOCl use could be minimized by neutralization of treated residuals with sodium bisulfite. Further research is needed, however, to evaluate the effect of NaOCl on ballast tank corrosion. 相似文献
6.
The stratigraphic nomenclature for the Lamington Volcanics in the southern part of the Tweed Shield Volcano is revised. An alkaline formation (the Kyogle Basalt) containing discontinuous rhyolitic‐agglomerate (the Homeleigh Agglomerate Member) and rhyolite flow (the Georgica Rhyolite Member) horizons is the basal unit of the volcanic succession. The Kyogle Basalt thins eastward where it is overlain by a subalkaline sequence comprising the Lismore Basalt, Nimbin Rhyolite, and Blue Knob Basalt respectively. The Lismore Basalt is composed predominantly of tholeiitic andesite with minor icelandite and sporadic flows of mildly alkaline rocks; tholeiitic andesites predominate in the Blue Knob Basalt. The Nimbin Rhyolite consists of rhyolite flows, and a relatively minor pyroclastic component (principally lapilli tuff). 相似文献
7.
A high-alumina tholeiitic andesite from the southern portion of the Tweed Shield Volcano in northeastern New South Wales contains abundant megacrysts of plagioclase (Ab50An46Or4) and megacrysts of aluminian bronzite (Ca4Mg71Fe25) and relatively Ca-poor aluminian augite (Ca36Mg41Fe20). The pyroxenes commonly occur as inclusions in the plagioclase megacrysts. Electron probe microanalyses of the pyroxene megacrysts indicate that they differ in character and composition from the groundmass ferromagnesian phases, namely a more Al- and Na-poor augite (Ca41Mg42Fe17) and olivine (Fa53). The bulk composition of the plagioclase megacrysts is slightly more Ab-rich than that of the groundmass plagioclase, but differences in the two compositions are extended by microanalyses of groundmass plagioclases. Evaluation of the megacryst compositions in the light of experimental data and analogous occurrences in alkaline volcanics leads to the interpretation that the megacrysts represent cognate precipitates formed at pressures broadly equivalent to the crust-mantle boundary. More important, they provide strong evidence for the high pressure origin of tholeiitic andesites, customarily interpreted as the products of low pressure fractional crystallization of tholeiitic magma. 相似文献
8.
The composition of the zooplankton community in a macrotidal (8 m tidal range), tropical estuarine system (Darwin Harbour,
Australia; 12o28′ S, 130o50′ E) was studied over a 2 year period with the goal of describing biodiversity and determining the environmental factors
that have the greatest impact on community structure. Most (82–84%) of the >73 μm plankton was composed of copepod nauplii
and copepodites, and plankton samples taken with larger, coarser meshed (150 and 350 μm) nets did not contain significant
numbers of larger (non-copepod) organisms. In all, 32 copepod species were recorded, with small euryhaline marine copepod
species such as Parvocalanus crassirostris, Bestiolina similis and Oithona aruensis dominating the zooplankton. Plankton abundances ranged between 30,000 and 110,000 m−3, and there were significant year (2003 > 2004), season (wet > dry) and site differences (inner harbour sites > outer harbour
sites), but negligible diurnal differences. Multivariate analyses identified three sample groups: (1) middle and outer harbour
sites, (2) inner harbour and river sites and (3) the river site during the wet seasons. Middle and outer harbour stations
were characterised by a diverse mixture of coastal copepods, whereas inner harbour and river sites were dominated by P. crassirostris and O. aruensis. During the wet season, there was a distinct copepod community within the Blackmore River, dominated by Acartia sinjiensis, Oithona nishidai and Pseudodiaptomus spp. Environmental variables (nutrients and chlorophyll a) were correlated with salinity, which had the strongest influence on community structure. There was a significant drop in
species richness from harbour to river sites. Small copepods of the families Paracalanidae and Oithonidae dominate tide-dominated
Australian tropical estuaries, whereas copepods belonging to the family Centropagidae (such as Gladioferens spp.) appear to be characteristic of wave-dominated estuaries in southern Australia. 相似文献
9.
Louis A. Tremblay Olivier Champeau Patrick L. Cahill Steve Pullan Natasha Grainger Ian C. Duggan 《新西兰海洋与淡水研究杂志》2019,53(1):97-112
Non-indigenous zooplankton species pose a biosecurity threat to New Zealand’s freshwater native taxa. Nine species are known to have established in New Zealand lakes to date. The spread of some zooplankton taxa is linked to the translocation of farmed fish, principally grass carp (Ctenopharyngodon idella), and recreational vessel movements. The aims of this study were to assess the effectiveness of a range of chemical and physical treatments for transport water and associated equipment to kill freshwater cladoceran, copepod, and rotifer zooplankton species, and their risk to non-target fish. Sodium chloride was the most effective and applicable chemical treatment tested at length in the cladoceran and, combined with physical treatment via mechanical filtration of water or hot water immersion of equipment (to also manage the risk of diapausing eggs), represents an effective option for the control of non-indigenous zooplankton, with limited impact on stenohaline fish. 相似文献
10.
Brown trout (Salmo trutta) are known to have effects on multiple trophic levels in New Zealand streams, but their impacts on lower trophic levels are less well understood within lentic systems. We examined the effects of brown trout removal using rotenone on zooplankton and phytoplankton community composition in the Upper Karori Reservoir, New Zealand. Significant shifts were observed in zooplankton and phytoplankton composition following removal of brown trout from the reservoir. Shifts in zooplankton community composition did not occur immediately following trout removal (February), but instead followed the likely timing of galaxiid spawning (July). The removal of brown trout likely resulted in reduced predation pressure on galaxiids. A major change occurred in the zooplankton community with the dominance shifting from larger crustaceans to smaller rotifers, indicating an increased predation pressure from the larval native galaxiid. A delayed response in zooplankton community composition change indicates rotenone was not the direct cause of this. A major shift in phytoplankton community composition occurred immediately following trout removal. This was not consistent with the trophic cascade hypothesis of reduced grazing pressure from larger zooplankton due to increased galaxiid predation as a result of brown trout removal. 相似文献