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Application of multiple sublethal stress indicators to assess the health of fish in Pamlico Sound following extensive flooding 总被引：1，自引：0，他引：1
S.?Marshall?AdamsEmail author Mark?S.?Greeley J.?McHugh?Law Edward?J.?Noga Judith?T.?Zelikoff 《Estuaries and Coasts》2003,26(5):1365-1382
Multiple indicators of sublethal stress (bioindicators) were used to assess the health and condition of two important estuarine fish species in the Pamlico Sound estuary following extensive flooding from three sequential hurricanes that occurred during early fall 1999. Bioindicators ranging from the biochemical to the reproductive and organism-level were used to assess the health of southern flounder and spot in Pamlico Sound compared to the health of these same species sampled from a relatively unaffected references site in lower Core Sound. Many of the physiological, reproductive, immunological, histopathological, and general condition indices suggested that both species, and particularly spot, in Pamlico Sound were sublethally stressed and in poorer condition than fish sampled from Core Sound. The major environmental stressors causing these sublethal stress responses in Pamlico Sound fish appears to be those related to episodic hypoxic exposure or a combination of effects associated with hypoxic conditions such as alterations in preferred habitat and food availability. Although fish populations in Pamlico Sound do not appear to be severely damaged or impaired at this time, organisms that are sublethally stressed can incur increased vulnerability to additional or future stressors such as modified physicochemical regimes, changes in food and habitat availability, and increases in infectious pathogens. Because of the low flushing rate (～1 yr) of Pamlico Sound, recovery rate may be exceptionally slow, prolonging any adverse effects of altered nutrient regimes (such as hypoxia) on the health and fitness of resident fish populations. Flooding from the 1999 hurricanes may have contributed to the short-term health and condition of finfish species in Pamlico Sound and also influenced longer-term recovery and ecological status of this system. Longer-term manifestation of effects from flooding may be of particular concern as the frequency of hurricanes is expected to increase over the next few years and the accelerated uses of the coastal zone places further stress on estuarine resources. 相似文献
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A S Kane M J Dykstra E J Noga R Reimschuessel A Baya C Driscoll H W Paerl J Landsberg 《Marine environmental research》2000,50(1-5):473-477
Lesions in estuarine finfish are associated with a variety of organisms including parasites and bacterial, viral, and fungal infectious agents. In addition, trauma, suboptimal water quality, and other abiotic stress factors may result in the loss of homeostasis. We have observed solitary ulcerative lesions on menhaden sampled from the Chesapeake Bay, Maryland, the Pimlico River, North Carolina, and the St. Johns River, Florida. Histologically, the lesions demonstrated a marked chronic inflammatory infiltrate and granulomas in response to fungal hyphae throughout large areas of exposed necrotic muscle. Gram-negative rod-shaped bacteria were also observed in the lesions, a common finding in ulcers of aquatic organisms. Similar observations in menhaden and other species have been described previously in the literature as ulcerative mycosis, mycotic granulomatosis, red spot disease, and epizootic ulcerative syndrome. Despite the many different known causes of fish lesions, the popular press and the scientific literature have recently emphasized Pfiesteria piscicida and other Pfiesteria-like dinoflagellates (and their bioactive compounds) as the primary causative agent for finfish lesions, particularly mycotic granulomatous ulcers in Atlantic menhaden. While some laboratory data suggest that Pfiesteria may play a role in field-observed lesions, much more cause-and-effect evidence is needed to determine the importance of other risk factors, both alone or and in combination with Pfiesteria. In order to better understand the etiology of lesion initiation and progression in estuarine finfish, accurate assessments of environmental conditions collected on appropriate temporal and spatial scales, and fish morphological indicators consistent with gross and histological pathologic terminology, should be used for reporting fish lesion observations and kills. Further, this outlook will help to avoid bias and may foster a broader perspective for examining the health of estuarine systems in general. 相似文献
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Noga Collins-Kreiner 《The Professional geographer》2013,65(4):589-591
This article explores the conceptual and empirical relationships among connectivity, employment, and specialization in advanced business services (ABS) in major cities in the United States. Correlation and regression analysis produces three chief empirical conclusions: First, the distribution of employment predicts and explains the level of connectivity; second, specialization does not predict connectivity; and, closer examination shows that these results vary by sector, which might relate to the informational characteristics of different types of ABS agglomerations. These conclusions demonstrate the continued relevance of agglomerative dynamics as they influence the networks and hierarchies of the ABS and corporate spatial structures. 相似文献
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Noga Collins‐Kreiner 《Geographical review》2008,98(2):197-213
ABSTRACT. In order to view the establishment of new religions centers and how they are received by local populations, I analyze such basic geographical concepts as scale, space, location, and image. I see how these can alter the perception and further refine the concept of spatial transgression in three case studies in Israel: the building of the Mormon Center in Jerusalem, the establishment of the Bahá‘í Gardens in Haifa, and the struggle to build a mosque in Nazareth. In this article I seek to identify the factors influencing the presence or absence of conflict to help explain the different “stories” revealed. The article also constitutes an addition to the literature on Israeli (and Palestinian) religiogeographical controversies by focusing on nonmainstream or nondominant cases and by comparing the relative roles of different factors that shape the success or failure of spatial transgressions in religious geography. 相似文献
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On the red coloration of saltern crystallizer ponds 总被引：3，自引：0，他引：3
To assess, respectively, the contribution of red bacteria of theHalobacterium-Haloferax-Haloarcula group and of the β-carotene-rich green algaDunaliella salina to the red colour of saltern crystallizer ponds, we studied the optical properties of the brines of NaCl-saturated saltern
ponds in Eilat, Israel, and quantified the pigments present in their biota. The absorption spectrum of the brines, as measured
using the opal glass method to reduce the interference by scattering, or using an integrating sphere, nearly corresponded
to thein vivo absorption spectrum of bacterioruberin-containing red archaeobacteria. However, extracts of the microbial community in organic
solvents were dominated by β-carotene, a pigment occurring in high concentrations in theDunaliella cells present, and bacterioruberin contributed only between 13 and 28 per cent of the total visible light absorption by the
extracts. The apparent discrepancy between these results can be explained by the very small in vivo optical cross-section
of β-carotene, which is densely packed in globules inside theD. salina cells. 相似文献
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This paper explores the inherent contradiction and conceptual conflict that arises when sacred sites are marketed as secular for the purpose of promoting tourism. The question of conflict is further frustrated within the context of Israel’s contested religious landscape and Israeli policy. Using a Lefebvrian framework, the historical development of the Bahai Gardens in Haifa, Israel, the tourism board’s promotion of the site as Haifa’s primary tourist designation, and the distinct spatial practices that have been used by both constituencies are investigated. Further, the authors posit that the Bahai Gardens are multi-dimensional spaces characterized by two different socio-spatial processes and practices that co-exist—the tourist’s and the pilgrim’s. These practices transform the holy site into a secular shared community asset. The paper concludes with a discussion of the socio-spatial implications of the case and its broader implications concerning the globalization of tourism and the efficacy of developing “layered” Lefebvrian triad to try and avoid conflict. 相似文献
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