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Coastal Zone (coastal + zone)
Selected AbstractsVariability and divergence in Pongamia pinnata (L.) Pierre germplasm , a candidate tree for biodieselGCB BIOENERGY, Issue 6 2009N. SUNIL Abstract Three explorations were undertaken in South East Coastal zone of India covering parts of Andhra Pradesh (AP) and Orissa states to collect Pongamia pinnata (L.) Pierre germplasm during March,June 2007. A total of 123 accessions were collected and seed data recorded were analyzed for morphometric traits viz., seed length, seed width, seed thickness, 100-seed weight and oil content. Variation in the collected germplasm was analyzed using anova, simple measures of variation and D2 statistics. Significant genetic variability between seed traits and oil content and association among the seed traits was recorded. Phenotypic variance was higher than genotypic variance for all the characters indicating dominant role of environment. High heritability (broad sense) for 100-seed weight (97.6%) and oil content (86.7%) indicated the reliability of these characters as selection criteria for plus trees. Genetic gain was maximum for 100-seed weight (62.6%) followed by oil content (30.5%). D2 analysis grouped the accessions into 12 clusters. Cluster XII and cluster IX were the most diverse based on the intercluster distance. Based on the observed diversity, Chittoor, Srikakulam and Adilabad districts of AP are most suitable for collecting diverse germplasm lines and also for in situ conservation. [source] Tracking environmental processes in the coastal zone for understanding and predicting Oregon coho (Oncorhynchus kisutch) marine survivalFISHERIES OCEANOGRAPHY, Issue 6 2003E.A. Logerwell Abstract To better understand and predict Oregon coho (Oncorhynchus kisutch) marine survival, we developed a conceptual model of processes occurring during four sequential periods: (1) winter climate prior to smolt migration from freshwater to ocean, (2) spring transition from winter downwelling to spring/summer upwelling, (3) the spring upwelling season and (4) winter ocean conditions near the end of the maturing coho's first year at sea. We then parameterized a General Additive Model (GAM) with Oregon Production Index (OPI) coho smolt-to-adult survival estimates from 1970 to 2001 and environmental data representing processes occurring during each period (presmolt winter SST, spring transition date, spring sea level, and post-smolt winter SST). The model explained a high and significant proportion of the variation in coho survival (R2 = 0.75). The model forecast of 2002 adult survival rate ranged from 4 to 8%. Our forecast was higher than predictions based on the return of precocious males (,jacks'), and it won't be known until fall 2002 which forecast is most accurate. An advantage to our environmentally based predictive model is the potential for linkages with predictive climate models, which might allow for forecasts more than 1 year in advance. Relationships between the environmental variables in the GAM and others (such as the North Pacific Index and water column stratification) provided insight into the processes driving production in the Pacific Northwest coastal ocean. Thus, coho may be a bellwether for the coastal environment and models such as ours may apply to populations of other species in this habitat. [source] Larval transport and retention of the spiny lobster, Panulirus argus, in the coastal zone of the Florida Keys, USAFISHERIES OCEANOGRAPHY, Issue 5 2002Cynthia Yeung Abstract The spiny lobster Panulirus argus is of ecological and commercial importance in the South Florida coast of the continental USA and throughout the Intra-Americas Sea. Essential spiny lobster habitat in South Florida is primarily located in the Florida Keys coastal zone (including the Dry Tortugas), where the dynamic regional circulation coupled with the long planktonic larval duration (6,12 months) of P. argus raises questions of larval retention and recruitment. Locally spawned phyllosomata entrained in the Florida Current are likely to be expatriated out of the Straits of Florida, which implies that the local spiny lobster population is sustained by the transport of larval recruits from upstream locations. We examined the physical processes that may influence recruitment. Transport processes in the Keys coastal zone are spatially variable. Observed and modelled data suggest that the upper Keys is a point of onshore larval transport via the inshore meandering of the Florida Current, and the lower Keys to Dry Tortugas region apoint of retention through wind-driven onshore/countercurrents and eddy recirculation. Eddies that propagate between the Dry Tortugas and the lower Keys facilitate the exchange of larvae between the Florida Current and the coastal zone. Northerly wind events associated with cold fronts can enhance recirculation of larvae in the upper Keys. The association of older larvae with the Florida Current front supports the hypothesis that spiny lobster larval recruits come from upstream sources in the Caribbean. [source] Coastal and ancient harbour geoarchaeologyGEOLOGY TODAY, Issue 1 2010N. Marriner What roles have human impacts and natural processes had in shaping the evolution of Mediterranean coastlines during the Holocene? Where, when and how did societies transform the coastal zone? At what scales and rhythms did these changes take place? What can ancient harbour sediments tell us about human-environment interactions? During the past 20 years, geoarchaeological research in the Mediterranean has attempted to understand the interplay between culture and nature, and more particularly how environments and processes have played a role in Holocene human occupation of the coastal zone. This approach has drawn on the multidisciplinary study of sediments, as archives of information, to attempt to differentiate between anthropogenic and natural factors, the latter, we argue, having played an increasingly secondary role with time. Three important spatial scales of analysis have emerged, local, regional and Mediterranean, all of which are outlined here. [source] Evaluation of time-space distributions of submarine ground water dischargeGROUND WATER, Issue 3 2005Makoto Taniguchi Submarine ground water discharge (SGD) rates were measured continuously by automated seepage meters to evaluate the process of ground water discharge to the ocean in the coastal zone of Suruga Bay, Japan. The ratio of terrestrial fresh SGD to total SGD was estimated to be at most 9% by continuous measurements of electrical conductivity of SGD. Semidiurnal changes of SGD due to tidal effects and an inverse relation between SGD and barometric pressure were observed. Power spectrum density analyses of SGD, sea level, and ground water level show that SGD near shore correlated to ground water level changes and SGD offshore correlated to sea level changes. SGD rates near the mouth of the Abe River are smaller than those elsewhere, possibly showing the effect of the river on SGD. The ratio of terrestrial ground water discharge to the total discharge to the ocean was estimated to be 14.7% using a water balance method. [source] Offshore renewable energy: ecological implications of generating electricity in the coastal zoneJOURNAL OF APPLIED ECOLOGY, Issue 4 2005ANDREW B. GILL Summary 1Global-scale environmental degradation and its links with non-renewable fossil fuels have led to an increasing interest in generating electricity from renewable energy resources. Much of this interest centres on offshore renewable energy developments (ORED). The large scale of proposed ORED will add to the existing human pressures on coastal ecosystems, therefore any ecological costs and benefits must be determined. 2The current pressures on coastal ecology set the context within which the potential impacts (both positive and negative) of offshore renewable energy generation are discussed. 3The number of published peer-review articles relating to renewable energy has increased dramatically since 1991. Significantly, only a small proportion of these articles relate to environmental impacts and none considers coastal ecology. 4Actual or potential environmental impact can occur during construction, operation and/or decommissioning of ORED. 5Construction and decommissioning are likely to cause significant physical disturbance to the local environment. There are both short- and long-term implications for the local biological communities. The significance of any effects is likely to depend on the natural disturbance regime and the stability and resilience of the communities. 6During day-to-day operation, underwater noise, emission of electromagnetic fields and collision or avoidance with the energy structures represent further potential impacts on coastal species, particularly large predators. The wider ecological implications of any direct and indirect effects are discussed. 7Synthesis and applications. This review demonstrates that offshore renewable energy developments will have direct and, potentially, indirect consequences for coastal ecology, with these effects occurring at different scales. Ecologists should be involved throughout all the phases of an ORED to ensure that appropriate assessments of the interaction of single and multiple developments with the coastal environment are undertaken. [source] A major fish stranding caused by a natural hypoxic event in a shallow bay of the eastern South Pacific OceanJOURNAL OF FISH BIOLOGY, Issue 7 2010E. Hernández-Miranda A massive beaching and mortality of fishes occurred in Coliumo Bay, a shallow bay located along the coast of the eastern South Pacific Ocean on 3 January 2008. This stranding was a consequence of an abrupt decrease in the dissolved oxygen concentration throughout the whole water column, due to the effect of intense upwelling along the coast off central-southern Chile. The main objectives of this study were: (1) to characterize taxonomically and biologically the fish species assemblage present in this beaching; (2) to evaluate several physiological indicators for the condition of the beached species at the time of their death; and (3) to assess the possible cause,effect mechanisms involved in the fishes death and the changes that took place in the fish community throughout the time. In this beaching, 26 fish species were identified: 23 teleosts, one myxiniform and two elasmobranchs. Most beached specimens were juveniles. Haematological and histological evidence indicate that severe hypoxia that lasted for at least 48 h was the most plausible cause of death. The main conclusion of this study is that the presence of oxygen-poor equatorial sub-surface water in the shallow coastal zone due to intense regional-scale upwelling caused the fish stranding. Although the effect of the hypoxic event was severe for the fish assemblage of Coliumo Bay, the rapid recuperation observed suggests that hypoxic events at the local spatial scale can be buffered by migration processes from the fish community inhabiting close by areas non-affected by low oxygen conditions. The effect that severe hypoxic events may have on larger spatial scales remains unknown. [source] Marginal formation of De Geer moraines and their implications to the dynamics of grounding-line recession,JOURNAL OF QUATERNARY SCIENCE, Issue 2 2005Mattias Lindén Abstract De Geer moraine ridges occur in abundance in the coastal zone of northern Sweden, preferentially in areas with proglacial water depths in excess of 150 m at deglaciation. From detailed sedimentological and structural investigations in machine-dug trenches across De Geer ridges it is concluded that the moraines formed due to subglacial sediment advection to the ice margin during temporary halts in grounding-line retreat, forming gradually thickening sediment wedges. The proximal part of the moraines were built up in submarginal position as stacked sequences of deforming bed diamictons, intercalated with glaciofluvial canal-infill sediments, whereas the distal parts were built up from the grounding line by prograding sediment gravity-flow deposits, distally interfingering with glaciolacustrine sediments. The rapid grounding-line retreat (ca. 400,m,yr,1) was driven by rapid calving, in turn enhanced by fast iceflow and marginal thinning of ice due to deforming bed conditions. The spatial distribution of the moraine ridges indicates stepwise retreat of the grounding line. It is suggested that this is due to slab and flake calving of the ice cliff above the waterline, forming a gradually widening subaqueous ice ledge which eventually breaks off to a new grounding line, followed by regained sediment delivery and ridge build-up. Copyright © 2005 John Wiley & Sons, Ltd. [source] Ecological implications of biomass and morphotype variations of bacterioplankton: an example in a coastal zone of the Northern Adriatic Sea (Mediterranean)MARINE ECOLOGY, Issue 2 2005Rosabruna La Ferla Abstract This study had the objective of quantifying the variability in abundance, cell volume, morphology and C content of a natural bacterioplankton community in a coastal zone of the North Adriatic Sea during two periods (February and June) of two consequent years (1996 and 1997). We used epifluorescence microscopy with Acridine Orange staining procedures and a microphotographic technique. Low variability in bacterial abundance (range 0.3,3.1 × 105 cells ml,1) occurred between summer and winter periods. Conversely, the cell volume and the calculated carbon content changed greatly with warm and cold periods (ranges: 0.015,0.303 ,m3 and 5.83,42.17 fg C cell,1, respectively). Elongated bacteria were dominant while coccoid cells prevailed only in February 1997. Biomass showed high variability (range 0.12,10.21 ,g C l,1) whilst the abundance did not show noticeable differences among the sampling periods. As a consequence, quantification of bacterial biomass based solely on cell abundance must be considered with caution because the true biomass could depend on variability in cell volumes and morphotypes. [source] A transcriptomic analysis of land-use impacts on the oyster, Crassostrea virginica, in the South Atlantic bightMOLECULAR ECOLOGY, Issue 11 2009ROBERT W. CHAPMAN Abstract Increasing utilization and human population density in the coastal zone is widely believed to place increasing stresses on the resident biota, but confirmation of this belief is somewhat lacking. While we have solid evidence that highly disturbed estuarine systems have dramatic changes in the resident biota (black and white if you will), we lack tools that distinguish the shades of grey. In part, this lack of ability to distinguish shades of grey stems from the analytical tools that have been applied to studies of estuarine systems, and perhaps more important, is the insensitivity of the biological end points that we have used to assess these impacts. In this study, we will present data on the phenotypic adjustments as measured by transcriptomic signatures of a resilient organism (oysters) to land-use practices in the surrounding watershed using advanced machine-learning algorithms. We will demonstrate that such an approach can reveal subtle and meaningful shifts in oyster gene expression in response to land use. Further, the data show that gill tissues are far more responsive and provide superior discrimination of land-use classes than hepatopancreas and that transcripts encoding proteins involved in energy production, protein synthesis and basic metabolism are more robust indicators of land use than classic biomarkers such as metallothioneins, GST and cytochrome P-450. [source] The use of a geographical information system for land-based aquaculture planningAQUACULTURE RESEARCH, Issue 4 2002Ian McLeod Abstract Site selection for aquaculture planning is a complex task involving the identification of areas that are economically, socially and environmentally suitable, available to aquaculture and commercially practicable. This paper reports upon a study into the use of a geographic information system (GIS) to assist in aquaculture planning. Using a case study in the site selection for land-based shrimp farming within the Australian coastal zone, we demonstrate that a GIS has potential to assist aquaculture planning. Our analysis is based on a sequential, two-stage approach. The first stage eliminates the grossly unsuitable portion of the study area through a preselection with low resolution, cheap and easily available data. The second stage then focuses on and ranks the remaining area using high resolution, possibly more expensive data. Finally, we use the GIS to present the results of the analysis in an easily accessible form. [source] Legal implications of mobile shorelines in Great BritainAREA, Issue 2 2009Derek J McGlashan This paper highlights the three legally defined property areas that lie in the coastal zone in Great Britain (land, foreshore and seabed), and considers the mechanisms used by the two legal systems that operate on the mainland (Scots and English law) to cope with natural processes of erosion and accretion. The two legal systems are shown to be slightly different in how they accommodate erosion and accretion. However, they both have difficulty in coherently addressing the issues of coastal mobility and land ownership, which raises important questions of social justice, as they are based on the perceptions of judges in historic cases. [source] Universality and variability in basin outlet spacing: implications for the two-dimensional form of drainage basinsBASIN RESEARCH, Issue 2 2009Rachel C. Walcott ABSTRACT It has been observed that the distance between the outlets of transverse basins in orogens is typically half of the distance between the main divide and the range front irrespective of mountain range size or erosional controls. Although it has been suggested that this relationship is the inherent expression of Hack's law, and/or possibly a function of range widening, there are cases of notable deviations from the typical half-width average spacing. Moreover, it has not been demonstrated that this general relationship is also true for basins in morphologically similar nonorogenic settings, or for those that do not extend to the main drainage divide. These issues are explored by investigating the relationship between basin outlet spacing and the 2-dimensional geometric properties of drainage basins (basin length, main valley length and basin area) in order to assess whether the basin outlet spacing-range width ratio is a universal characteristic of fluvial systems. We examined basins spanning two orders of magnitude in area along the southern flank of the Himalayas and the coastal zone of southeast Africa. We found that the spacing between basin outlets (Los) for major transverse basins that drain the main divide (range-scale basins) is approximately half of the basin length (Lb) for all basins, irrespective of size, in southeast Africa. In the Himalayas, while this ratio was observed for eastern Himalayan basins (a region where the maximum elevations coincided with the main drainage divide), it was only observed in basins shorter than ,30 km in the western and central Himalayas. Our analysis indicates that basin outlet spacing is consistent with Hack's law, apparently because the increase in basin width (represented by outlet spacing) with basin area occurs at a rate similar to the increase in main stream length (Lv) with basin area. It is suggested that most river systems tend towards an approximately diamond-shaped packing arrangement, and this applies both to the nonorogenic setting of southeast Africa as well as most orogenic settings. However, in the western Himalayas shortening associated with localised rock uplift appears to have occurred at length scales smaller than most the basins examined. As a result rivers in basins longer than ,30 km have been unable to erode in a direction normal to the range front at a sufficiently high rate to sustain this form and have been forced into an alternative, and possibly unstable, packing arrangement. [source] Factors influencing the challenges of modelling and treating fecal indicator bacteria in surface watersECOHYDROLOGY, Issue 4 2009Cristiane Q. Surbeck Abstract In the United States, thousands of creeks, rivers, and coastal zones are listed as impaired in the Clean Water Act's 303(d) list. The number one general cause of impairments is denoted as ,pathogens', which can include known pathogenic organisms or, more commonly, fecal indicator bacteria (FIB), such as fecal coliform bacteria, Escherichia coli, and enterococci bacteria. Despite efforts by water quality managers to reduce FIB in surface waters via treatment, successful and significant reduction of FIB has been difficult to achieve to meet water quality standards. In addition, current efforts to numerically model FIB concentrations in surface waters do not consider many complexities associated with FIB as a pollutant. Reasons for the challenge of treating and modelling FIB are their varied sources and mechanisms of survival and decay in the environment. This technical note addresses this challenge by discussing the nature of FIB, their sources, and their fate and transport mechanisms. Sources of FIB to surface waters include wastewater, stormwater and dry-weather runoff, and animals. Mechanisms of pathogen indicator occurrence in surface waters are transport in stormwater, ecological proliferation, and interaction with sediments. Copyright © 2009 John Wiley & Sons, Ltd. [source] In situ on-line toxicity biomonitoring in water: Recent developmentsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 9 2006Almut Gerhardt Abstract ,In situ on-line biomonitoring is an emerging branch of aquatic biomonitoring. On-line biomonitoring systems use behavioral and/or physiological stress responses of caged test organisms exposed in situ either in a bypass system or directly instream. Sudden pollution waves are detected by several existing single-species on-line biomonitors, which until now have been placed mostly in streamside laboratories. However, recent achievements have been multispecies biomonitors, mobile biomonitors for direct in-stream use, development of new instruments, new methods for data analysis and alarm generation, biomonitors for use in soil and sediment, and scientific research supporting responses as seen in on-line biomonitors by linking them to other biological and ecological effects. Mobile on-line monitoring platforms containing an array of biomonitors, biosensors, and chemical monitoring equipment might be the future trend, especially in monitoring transboundary rivers at country borders as well as in coastal zones. [source] Germination of Salicornia bigelovii Ecotypes under Stressing Conditions of Temperature and Salinity and Ameliorative Effects of Plant Growth-promoting BacteriaJOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 3 2007E. O. Rueda-Puente Abstract Salinity is a major stress condition. Salicornia bigelovii is a valuable edible halophyte, considered to be a promising resource for cultivation in arid coastal zones. Its productivity depends on the supplementary provision of nitrogen, for which an option is chemical fertilization. Nevertheless, indiscriminate use of chemical fertilizers contributes to the problem of increased salinity. The inoculation of plant growth-promoting bacteria (PGPB) represents an alternative. Seed ecotypes from four coastal areas [Santa Rosa Chica, Santa Rosa Grande, Santa Cruz and Cerro Prieto (CP), Sonora, México] were collected, in order to inoculate them with two species of PGPB (Azospirillum halopraeferens and Klebsiella pneumoniae). Two germination tests were carried out to study the effect of salinity, temperature regime (night/day) and inoculation with PGPB on germination (percentage and rate), plant height, root length and biomass produced (fresh and dry matter). In the first test, all four ecotypes were considered, whereas in the second test only the CP ecotype was involved because it was found to be the outstanding ecotype in the previous test. Results showed inhibition of germination when salinity was higher in all ecotypes except CP. The CP ecotype showed a decrease of seed germination with an increase in NaCl concentrations at all temperatures tested. However, when it was inoculated with both PGPB, the germination percentage was influenced. [source] Phylogeography of the introduced species Rattus rattus in the western Indian Ocean, with special emphasis on the colonization history of MadagascarJOURNAL OF BIOGEOGRAPHY, Issue 3 2010Charlotte Tollenaere Abstract Aim, To describe the phylogeographic patterns of the black rat, Rattus rattus, from islands in the western Indian Ocean where the species has been introduced (Madagascar and the neighbouring islands of Réunion, Mayotte and Grande Comore), in comparison with the postulated source area (India). Location, Western Indian Ocean: India, Arabian Peninsula, East Africa and the islands of Madagascar, Réunion, Grande Comore and Mayotte. Methods, Mitochondrial DNA (cytochrome b, tRNA and D-loop, 1762 bp) was sequenced for 71 individuals from 11 countries in the western Indian Ocean. A partial D-loop (419 bp) was also sequenced for eight populations from Madagascar (97 individuals), which were analysed in addition to six previously published populations from southern Madagascar. Results, Haplotypes from India and the Arabian Peninsula occupied a basal position in the phylogenetic tree, whereas those from islands were distributed in different monophyletic clusters: Madagascar grouped with Mayotte, while Réunion and Grand Comore were present in two other separate groups. The only exception was one individual from Madagascar (out of 190) carrying a haplotype that clustered with those from Réunion and South Africa. ,Isolation with migration' simulations favoured a model with no recurrent migration between Oman and Madagascar. Mismatch distribution analyses dated the expansion of Malagasy populations on a time-scale compatible with human colonization history. Higher haplotype diversity and older expansion times were found on the east coast of Madagascar compared with the central highlands. Main conclusions, Phylogeographic patterns supported the hypothesis of human-mediated colonization of R. rattus from source populations in either the native area (India) or anciently colonized regions (the Arabian Peninsula) to islands of the western Indian Ocean. Despite their proximity, each island has a distinct colonization history. Independent colonization events may have occurred simultaneously in Madagascar and Grande Comore, whereas Mayotte would have been colonized from Madagascar. Réunion was colonized independently, presumably from Europe. Malagasy populations may have originated from a single successful colonization event, followed by rapid expansion, first in coastal zones and then in the central highlands. The congruence of the observed phylogeographic pattern with human colonization events and pathways supports the potential relevance of the black rat in tracing human history. [source] The global distribution of infant mortality: a subnational spatial viewPOPULATION, SPACE AND PLACE (PREVIOUSLY:-INT JOURNAL OF POPULATION GEOGRAPHY), Issue 3 2008Adam Storeygard Abstract We describe the compilation of a spatially explicit data-set detailing infant mortality rates in over 10,000 national and subnational units worldwide, benchmarked to the year 2000. Although their resolution is highly variable, subnational data are available for countries representing over 90% of the non-OECD population. Concentration of global infant deaths is higher than implied by national data alone. Assigning both national and subnational data to map grid cells so that they may be easily integrated with other geographical data, we generate infant mortality rates for environmental regions, including biomes and coastal zones, by continent. Rates for these regions also show striking refinements from the use of the higher resolution data. Possibilities and limitations for related work are discussed. Copyright © 2008 John Wiley & Sons, Ltd. [source] | ||||||||||||||||