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Coastal Areas (coastal + area)
Selected AbstractsMonitoring a Marine Coastal Area: Use of Mytilus galloprovincialis and Mullus barbatus as BioindicatorsMARINE ECOLOGY, Issue 2002Ilaria Corsi Abstract. Samples of Mytilus galloprovincialis and Mullus barbatus were collected in eight coastal sites along the South Adriatic and Ionic coasts of Italy in spring 2000 for a survey of coastal pollution in the Mediterranean basin. Specimens were analysed using an integrated approach based on residue analysis of common aquatic pollutants like organochlorines such as hexachlorobenzene (HCB), DDTs and polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), heavy metals and nonylphenols (NPnE) and biomarker responses such as acetylcholinesterase (AChE) activity, and the two specific P450 activities benzo(a)pyrene monooxygenase (BPMO) and 7-ethoxyre-sorufin-(9-deethylase (EROD). Biological and morphological parameters like somatic liver index (SLI), gonadosomatic index (GSI) and gonadal and gamete histology (eggs and sperms) were also evaluated in red mullet samples. A contamination gradient in which several hot spots occur were revealed in this study. The hot spots account for high levels of organochlorines in both species near incinerators and of PAHs in harbour areas. Levels of both NPnE and AChE activity were highest in two protected marine areas and were within detectable limits in others. This finding was confirmed by P450 activities, in which maximum levels were detected in harbours and protected marine areas. No morphological alterations of male and female gonads were observed on the histological level. [source] Variability of UVR Effects on Photosynthesis of Summer Phytoplankton Assemblages from a Tropical Coastal Area of the South China Sea,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 4 2007Kunshan Gao From June to September 2005, we carried out experiments to determine the ultraviolet radiation (UVR) -induced photoinhibition of summer phytoplankton assemblages from a coastal site of the South China Sea. Variability in taxonomic composition was determined throughout the summer, with a peak chlorophyll a (chl a,20 ,g chl a L,1) dominated by the diatom Skeletonema costatum that was detected early in the study period; the rest of the time samples were characterized by monads and flagellates, with low chl a values (1,5 chl a ,g L,1). Surface water samples were placed in quartz tubes, inoculated with radiocarbon and exposed to solar radiation for 2,3 h to determine photosynthetic rates under three quality radiation treatments (i.e. PAB, 280,700 nm; PA, 320,700 nm and P, 400,700 nm) using different filters and under seven levels of ambient irradiance using neutral density screens (PvsE curves). UVR inhibition of samples exposed to maximum irradiance (i.e. at the surface) varied from ,12.2% to 50%, while the daytime-integrated UVR-related photoinhibition in surface seawater varied from ,62% to 7%. The effects of UVR on the photosynthetic parameters PBmax and Ek were also variable, but UV-B accounted for most of the observed variability. During sunny days, photosynthesis of microplankton (>20 ,m) and piconanoplankton (<20 ,m) were significantly inhibited by UVR (mostly by UV-B). However, during cloudy days, while piconanoplankton cells were still inhibited by UVR, microplankton cells used UVR (mostly UV-A) as the source of energy for photosynthesis, resulting in higher carbon fixation in samples exposed to UVR than the ones exposed only to photosynthetically active radiation (PAR). Our results indicate that size structure and cloudiness clearly condition the overall impact of UVR on phytoplankton photosynthesis in this tropical site of South China. In addition, model predictions for this area considering only PAR for primary production might have underestimated carbon fixation due to UVR contribution. [source] Balancing the Need to Develop Coastal Areas with the Desire for an Ecologically Functioning Coastal Environment: Is Net Ecosystem Improvement Possible?RESTORATION ECOLOGY, Issue 1 2005R.M. Thom Abstract The global human population is growing exponentially, close to a majority lives and works near the coast, and coastal commerce and development are critical to the economies of many nations. Hence, coastal areas will continue to be a major focus of development and economic activity. People desire the economic advantages provided by coastal development along with the fisheries and social commodities supported by estuarine and coastal ecosystems. Because of these facts, we view the challenge of balancing coastal development with enhancing nearshore marine and estuarine ecosystems (i.e., net ecosystem improvement) as the top priority for coastal researchers in this century. Our restoration research in Pacific Northwest estuaries and participation in nearshore project design and impact mitigation has largely dealt with these competing goals. To this end, we have applied conceptual models, comprehensive assessment methods, and principles of restoration ecology, conservation biology, and adaptive management to incorporate science into decisions about uses of estuarine systems. Case studies of Bainbridge Island and the Columbia River demonstrate the use of objective, defensible methods to prioritize tidally influenced shorelines and habitats (i.e., riparian forests, marshes, unvegetated flats, rocky shores, seagrass meadows, kelp forests) for preservation, conservation, and restoration. Case studies of Clinton, Washington, and Port Townsend, Washington, demonstrate the incorporation of an ecological perspective and technological solutions into design of overwater structures to minimize impacts on nearshore ecosystems. Adaptive management has allowed coastal development and restoration uncertainties to be better evaluated, with the information used to improve management decisions. Although unproven on a large scale, we think these kinds of methods can contribute to the net improvement of already degraded ecosystems. The ingredients include applied science to understand the issues, education, incentives, empirical data, cumulative impact analysis, and an effective adaptive management program. Because the option of net ecosystem improvement is often more costly than alternatives such as no net loss, commitment by the local or regional community to this approach is essential. [source] Trade-Offs between Species Conservation and the Size of Marine Protected AreasCONSERVATION BIOLOGY, Issue 1 2010P. M. CHITTARO áreas marinas protegidas; conservación de la biodiversidad; relaciones especies,área Abstract:,Moving from single-species- to ecosystem-based management requires an understanding of how community-level attributes such as diversity change with area. We used survey data from bottom trawls to examine spatial patterns of species richness in U.S. Pacific coastal fishes. Specifically, we generated and compared species,area relationships (SARs) for species classified into several groups on the basis of maximum body size, trophic level, diet, maximum depth, geographic affinity, and taxonomic order. Because SARs among groups were not parallel and z values varied significantly for several groups, groups of species were under- or overrepresented (depending on the size of the area) relative to their proportions in the entire community (i.e., entire U.S. Pacific coast). In this way, differences in SARs help demonstrate trade-offs between species representation and coastal area and suggest strategies (such as targeting the protection of habitats and locations where a particular species or groups of species are maximized) that may minimize the size of marine protected areas (MPAs) but protect diversity at the level of the community and functional group. Resumen:,El traslado del manejo de una sola especie al manejo basado en ecosistemas requiere del entendimiento de los cambios en atributos de la comunidad como el cambio de diversidad con el área. Utilizamos datos de muestreo de redes de arrastre para examinar patrones espaciales de la riqueza de especies en peces costeros del Pacífico en E. U. A. Específicamente, generamos y comparamos relaciones especies,área (REAs) para especies clasificadas en varios grupos con base en la talla máxima, nivel trófico, profundidad máxima, afinidad geográfica y orden taxonómico. Debido a que las REAs entre grupos no fueron paralelas y que los valores de z variaron significativamente para varios grupos, los grupos de especies estuvieron sub- o sobre- representados (dependiendo del tamaño del área) en relación con sus proporciones en toda la comunidad (i.e., toda la costa del Pacífico en E. U. A.). De esta manera, las diferencias en REAs ayudan a demostrar el balance entre la representación de especies y el área costera y sugieren estrategias (como la protección de hábitats y localidades donde se maximiza una especie o grupo de especies) que pueden minimizar el tamaño de áreas marinas protegidas pero proteger la diversidad al nivel de la comunidad y grupo funcional. [source] Diversity, distinctiveness and conservation status of the Mediterranean coastal dung beetle assemblage in the Regional Natural Park of the Camargue (France)DIVERSITY AND DISTRIBUTIONS, Issue 6 2001Jorge Miguel Lobo Abstract. The Mediterranean region as a whole has the highest dung beetle species richness within Europe. Natural coastal habitats in this region are among those which have suffered severe human disturbance. We studied dung beetle diversity and distinctiveness within one of the most important coastal protected areas in the west Euro-Mediterranean region (the regional Park of Camargue, southern France) and made comparisons of dung beetle assemblages with other nearby Mediterranean localities, as well as with other coastal protected area (Doñana National Park, Spain). Our finding showed that: (1) The species richness of coastal habitats in the Camargue is low and only grasslands showed a similar level of species richness and abundance to inland habitats of other Mediterranean localities. The unique habitats of the coastal area (beaches, dunes and marshes) are largely colonized by species widely distributed in the hinterland. (2) In spite of their low general distinctiveness, dune and marsh edges are characterized by the occurrence of two rare, vulnerable, specialized and large roller dung beetle species of the genus Scarabaeus. As with other Mediterranean localities, current findings suggest a recent decline of Scarabaeus populations and the general loss of coastal dung beetle communities in Camargue. (3) The comparison of dung beetle assemblages between the Camargue and Doñana shows that, in spite of the low local dung beetle species richness in the Camargue, the regional dung beetle diversity is similar between both protected areas. Unique historical and geographical factors can explain the convergence in regional diversity as well as the striking divergence in the composition of dung beetle assemblages between both territories. [source] Comparison of LiDAR waveform processing methods for very shallow water bathymetry using Raman, near-infrared and green signalsEARTH SURFACE PROCESSES AND LANDFORMS, Issue 6 2010Tristan Allouis Abstract Airborne light detection and ranging (LiDAR) bathymetry appears to be a useful technology for bed topography mapping of non-navigable areas, offering high data density and a high acquisition rate. However, few studies have focused on continental waters, in particular, on very shallow waters (<2,m) where it is difficult to extract the surface and bottom positions that are typically mixed in the green LiDAR signal. This paper proposes two new processing methods for depth extraction based on the use of different LiDAR signals [green, near-infrared (NIR), Raman] of the SHOALS-1000T sensor. They have been tested on a very shallow coastal area (Golfe du Morbihan, France) as an analogy to very shallow rivers. The first method is based on a combination of mathematical and heuristic methods using the green and the NIR LiDAR signals to cross validate the information delivered by each signal. The second method extracts water depths from the Raman signal using statistical methods such as principal components analysis (PCA) and classification and regression tree (CART) analysis. The obtained results are then compared to the reference depths, and the performances of the different methods, as well as their advantages/disadvantages are evaluated. The green/NIR method supplies 42% more points compared to the operator process, with an equivalent mean error (,4·2,cm verusu ,4·5,cm) and a smaller standard deviation (25·3,cm verusu 33·5,cm). The Raman processing method provides very scattered results (standard deviation of 40·3,cm) with the lowest mean error (,3·1,cm) and 40% more points. The minimum detectable depth is also improved by the two presented methods, being around 1,m for the green/NIR approach and 0·5,m for the statistical approach, compared to 1·5,m for the data processed by the operator. Despite its ability to measure other parameters like water temperature, the Raman method needed a large amount of reference data to provide reliable depth measurements, as opposed to the green/NIR method. Copyright © 2010 John Wiley & Sons, Ltd. [source] Shifting altitudinal distribution of outbreak zones of winter moth Operophtera brumata in sub-arctic birch forest: a response to recent climate warming?ECOGRAPHY, Issue 2 2007Snorre B. Hagen Climatic change is expected to affect the extent and severity of geometrid moth outbreaks, a major disturbance factor in sub-arctic birch forests. Previous studies have reported that the two geometrid species involved, autumnal moth and winter moth, differ in their temperature requirements and, consequently, in their altitudinal and latitudinal distribution patterns. In this study, we document the altitudinal distribution of winter moth outbreaks in a large coastal area in northern Norway. We show that, in the present winter moth outbreak, defoliated birch stands were seen as distinct zones with a rather constant width in the uppermost part of the forest and where the upper limit coincided with the forest line. The outbreak zone closely followed the spatially variable forest line as an undulating belt, although some of the variation in outbreak zone width was also related to variation in topographical variables, such as distance from the coast, forest line altitude, and slope of the terrain. A distinct outbreak zone at the altitudinal forest line is the typical picture that has been depicted in more qualitative historical records on previous outbreaks of autumnal moth rather than winter moth. We suggest that the recent documented climate warming in this region may have induced a shift in distribution of the winter moth both relative to topography and geography. Further investigation is, however, required to substantiate these suspicions. [source] Environmental determinants correlated to Vibrio harveyi -mediated death of marine gastropodsENVIRONMENTAL MICROBIOLOGY, Issue 1 2010Youhei Fukui Summary Vibrio harveyi is an emerging pathogen that causes mass mortality in a wide variety of marine animal species; however, it is still unclear which environmental determinants correlate V. harveyi dynamics and the bacterium-mediated death of marine animal life. We conducted a correlation analysis over a 5-year period (2003,2007) analysing the following data: V. harveyi abundance, marine animal mortality and environmental variables (seawater temperature, salinity, pH, chlorophyll a, rainfall and total viable bacterial counts). The samples were collected from a coastal area in northern Japan, where deaths of a marine gastropod species (Haliotis discus hannai) have been reported. Our analysis revealed significant positive correlations between average seawater temperature and average V. harveyi abundance (R = 0.955; P < 0.05), and between average seawater temperature and V. harveyi -mediated abalone death (R = 0.931; P < 0.05). Based on the regression model, n°C rise in seawater temperature gave rise to a 21n -fold increase in the risk of mortality caused by V. harveyi infection. This is the first report providing evidence of the strong positive correlation between seawater temperature and V. harveyi -mediated death of marine species. [source] Regional socio-economic importance of fisheries in FinlandFISHERIES MANAGEMENT & ECOLOGY, Issue 4-5 2001J. Virtanen The total value of Finnish fisheries production in 1997 was almost FIM 2 billion. The bulk of this sum was from processing and wholesaling, but in terms of value added, somewhat more than half was contributed by the primary sector, i.e. fishing and fish farming. In economic terms, fisheries accounted for 0.1% of gross domestic product (GDP) in 1997 and the relative job creation capacity was 0.15%. This paper examines the structure of Finnish fisheries in terms of production value and employment. It also considers the level of dependency on fisheries and of value added along the production chain. The focus is on concentration of the industry and on input to the economy at the regional level. The concentration of fisheries and regional dependence on fisheries are assessed in absolute and relative terms. Examining employment and value added in these two ways enables the regional nature of fisheries to be shown in greater detail. The input of fisheries to the regional economy is examined by the share of value added and by location quotients. The location quotient compares an area's share of a particular activity with that area's share of some basic or aggregated phenomenon. The location quotient showed that fisheries have importance not only in the coastal area but also inland. [source] Growth and movement patterns of early juvenile European anchovy (Engraulis encrasicolus L.) in the Bay of Biscay based on otolith microstructure and chemistryFISHERIES OCEANOGRAPHY, Issue 3 2010NAROA ALDANONDO Abstract Various hypotheses have been put forward to explain the mechanisms in the Bay of Biscay that result in a good recruitment of European anchovy. Anchovy larvae from the spawning area in the Gironde River plume are advected towards off-shelf waters, where juveniles are commonly observed. Otolith microstructural and chemical analysis were combined to assess the importance of this off-shelf transport and to determine the relative contribution of these areas for anchovy survival. Chemical analysis of otoliths showed that anchovy juveniles in the Bay of Biscay can be divided into two groups: a group that drifts towards off-shelf waters early in their life and returns later, and a group that remains in the low salinity waters of the coastal area. The first group presents significantly faster growth rates (0.88 mm day,1) than those remaining in the coastal waters (0.32 mm day,1). This may be due to off-shelf waters being warmer in spring/summer, and to the fact that the lower food concentration is compensated for by higher prey visibility. Furthermore, the group of juveniles that drifted off the spawning area and had faster growth rates represents 99% of the juvenile population. These findings support the hypothesis that anchovy in the Bay of Biscay may use off-shelf waters as a spatio-temporal loophole, suggesting that transport off the shelf may be favourable for recruitment. [source] A numerical study of inferred rockfish (Sebastes spp.) larval dispersal along the central California coastFISHERIES OCEANOGRAPHY, Issue 1 2010CHRISTINE H. PETERSEN Abstract Successful recruitment of marine fishes depends on survival during early life-history stages, which is influenced by oceanic advection due to its impact on coastal trophodynamics and transport processes. Here we evaluate the influence of ocean circulation on the dispersal of rockfish (Sebastes spp.) larvae along the central California coast using an implementation of the Regional Ocean Modeling System, driven at the surface by output from the Coupled Ocean Atmosphere Mesoscale Prediction System. Thousands of floats simulating rockfish larval propagules, constrained to follow fixed depths, were released over a broad coastal area at 2-day intervals, and transported by simulated ocean currents at depths of 1, 7, 20, 40, and 70 m. Trajectory statistics are averaged across the 4-yr period from January 2000 through December 2003 to reveal mean trajectory direction, net displacement, fractional cross-shore loss, and duration of retention for different seasons. On average, near-surface propagules originating nearshore are transported offshore during the upwelling season, whereas deeper propagules move alongshore to the north. This vertical shear vanishes during winter, with most floats moving alongshore to the north, regardless of depth. After 35 days in the water column, typical transport distances were ,50 km for floats remaining nearshore and ,150 km for floats over the midshelf and slope. Implications for performance of marine reserves for rockfish conservation are discussed. Our results also provide evidence for a strong semiannual pattern of coastal retention rates, with high export of near-surface drifters during the upwelling season. In contrast, high rates of shelf retention occurred for releases at 20 m and deeper during summer, and at all depths during winter. [source] Interannual variability in hatching period and early growth of juvenile walleye pollock, Theragra chalcogramma, in the Pacific coastal area of HokkaidoFISHERIES OCEANOGRAPHY, Issue 3 2007AKIRA NISHIMURA ABSTRACT Juvenile walleye pollock of the Japanese Pacific population were collected from the Funka Bay [spawning ground; 16,64 mm fork length (FL)] in spring and the Doto area (nursery ground; 70,146 mm FL) in summer. Hatch dates were estimated by subtracting the number of otolith daily increments from sampling dates, and their early growth was back-calculated using otolith radius,somatic length relationships. Interannual change of the hatching period was observed during 2000,02, and the peaks ranged from mid-February in 2000 to early-April in 2002. In 2000, when a strong year class occurred, early life history of the surviving juveniles could be characterized by early hatching and slower growth in the larval stage (<22 mm length). Higher growth rate in 2001 and 2002 did not always lead to good survival and recruitment success. Even though their growth was slow in 2000, the larvae hatched early in the season had larger body size on a given date than faster-growing larvae hatched in later season in 2001 and 2002. Bigger individuals at a certain moment may have advantage for survival. The delay of hatching period may result in higher size-selective mortality, and as a necessary consequence, back-calculated growth in 2001 and 2002 could shift towards higher growth rate, although abundance of such a year class would be at the lower level. Variability in spawning period, early growth and their interaction might have a strong relation to larval survival through cumulative predation pressure or ontogenetic changes in food availability. [source] Triassic metasedimentary successions across the boundary between the southern Apennines and the Calabrian Arc (northern Calabria, Italy)GEOLOGICAL JOURNAL, Issue 2 2005A. Iannace Abstract The boundary area between the Apenninic fold-and-thrust belt and the crystalline Calabrian Arc, located around Sangineto in northern Calabria, has been investigated. New geological mapping in the Sant'Agata area has been performed on the Triassic successions traditionally attributed to the metasedimentary San Donato Unit. This, coupled with a reappraisal of the stratigraphy and tectonics of coeval successions present more to the south in the Cetraro Unit, results in a new reconstruction of the Triassic evolution of all the metasedimentary successions found in the region. Four informal stratigraphic units have been distinguished in the S. Agata area. The lowest one (Unit A) consists of well-bedded metalimestones and bioturbated marly limestones that correlate with Ladinian,Carnian carbonates in nearby areas. A second unit (Unit B), never recognized before, contains a complex alternation of dolomites, phyllites and some meta-arenites containing several beds of Cavernoso facies, attributed to the Carnian. They grade upward to platform and platform-margin dolomites of Norian,Rhaetian age (Unit C) that in turn are replaced upward and laterally by a fourth unit (Unit D) consisting of well-bedded, dark dolomites and metalimestones with marly interlayers locally found as resedimented large blocks in slope conglomerates. Unit D correlates with Rhaetian,Liassic beds in nearby areas. Several pieces of evidence of post-metamorphic contractional tectonics, with 140°N and 30°N trends, are found together with evidence of SW-directed extension. The siliciclastic Carnian beds of Unit B are correlated with the phyllites of Cetraro, formerly believed to be Middle Triassic; moreover, it is suggested that in the Cetraro area Unit C is almost totally replaced by Unit D. This demonstrates that the former distinction between the two tectonic units in the whole area has to be discarded. We have made a general palaeoenvironmental reconstruction which progresses laterally, during Ladinian,Carnian times, from (i) a coastal, mixed siliciclastic,carbonate,evaporitic area at Cetraro to (ii) a transitional carbonate shelf where siliciclastic input was only episodic, and finally to (iii) a bioconstructed margin which was later replaced by a steepened margin created by tectonic instability. Starting from the Norian, subsidence shifted toward the former coastal area where an intraplatform, restricted basin developed. The proposed stratigraphy corresponds closely to the Alpujarride units of the Betic Cordillera, Spain. Moreover, it is shown that strong affinities also exist, in terms of the structural framework, with the metamorphic units of Tuscany and Liguria. Copyright © 2005 John Wiley & Sons, Ltd. [source] Temporal patterns of growth in larval cohorts of the Japanese sardine Sardinops melanostictus in a coastal nursery areaJOURNAL OF FISH BIOLOGY, Issue 6 2008G. Plaza Growth patterns of larval sardine Sardinops melanostictus were studied in a coastal nursery area, in southern Japan for four monthly hatch cohorts of larvae (November, December, January and February) for the 2003,2004 and 2004,2005 seasons. Laird,Gompertz models were fitted to each cohort using both total length (LT)-at-age at capture and mean LT -at-age data derived from backcalculations. In both approaches, the absolute daily growth rates (GR) and absolute daily growth rates at the inflection point (GXO) were estimated. In parallel, individual growth rates (GI) were derived from backcalculated LT (LB). Growth showed the following general common patterns irrespective of hatch month, season and methods: (1) significant Laird,Gompertz fits, (2) asymptotic growth, (3) a decrease in GR after the inflexion point, except for February for the 2003,2004 season that showed an apparent constant growth pattern, (4) six in eight cohorts showed GXO ranging from 0·8 to 1·2 mm day,1 and (5) a decreasing tendency of GI from 1·75 to 0·24 mm day,1, from first feeding through the first month of larval life. The contrasting pattern between the 2003,2004 and the 2004,2005 seasons were: (1) allometric v. logarithmic (ln) LT and otolith radius relationships, (2) low GXOv. high GXO, (3) high GRv. low GR when growth turned asymptotic, (4) low GXOv. high GXO when monthly hatch cohorts were combined and (5) LB and GI not differing among monthly hatch cohorts. The differences in growth patterns and growth rates between seasons seemed to be linked to the influx of warmer and oligotrophic waters of the Kuroshio Current that triggered an increase of 3° C in the coastal area for the 2003,2004 seasons. In the overall context, however, the high GXO, within cohorts and seasons reported in the current study, suggests that either sea surface temperature (SST) or food availability, or both are in the optimal range of preferences for S. melanostictus larvae. Consequently, nearshore coastal areas seem to be playing an important role as a nursery area for the larval stage of this species. [source] 160 Copepodology for the Phycologist with Apologies to G. E. HutchensonJOURNAL OF PHYCOLOGY, Issue 2003P. A. Tester Heterocapsa triquetra is one of the most common bloom forming dinoflagellates found in estuaries and near shore regions around the world. In order to bloom, H. triquetra optimizes a suite of factors including low grazing pressure, increased nutrient inputs, alternative nutrient sources, and favorable salinity and hydrodynamic conditions, as well as the negative factors of temperature-limited growth, short day lengths, and periods of transient light limitation. The prevailing environmental conditions associated its wintertime blooms are largely the result of atmospheric forcing. Low-pressure systems moved through coastal area at frequent intervals and are accompanied by low air temperatures and rainfall. Runoff following the rainfall events supplies nutrients critical for bloom initiation and development. Heterocapsa triquetra blooms can reach chl a levels >100 mg L,1 and cell densities between 1 to 6×106 L,1. As the blooms develop, nutrient inputs from the river became insufficient to meet growth demand and H. triquetra feeds mixotrophically, reducing competition from co-occurring phytoplankton. Cloud cover associated with the low-pressure systems light limit H. triquetra growth as do low temperatures. More importantly though, low temperatures limit micro and macrozooplankton populations to such an extent that grazing losses are minimal. [source] Anthropogenic changes in the landscape of west Java (Indonesia) during historic times, inferred from a sediment and pollen record from Teluk BantenJOURNAL OF QUATERNARY SCIENCE, Issue 3 2004Sander van der Kaars Abstract Palynological and charcoal analyses of shallow marine core 98-28 from the northern coastal area of West Java provide a regional vegetation history during the last few centuries. Reliable chronostratigraphical control is provided by 210Pb analyses and the occurrence of the 1883 Krakatau ash/tsunami layer as a time marker. The results permit the distinction of four successive stages, reflecting increased disturbance and land clearance, with some evidence for the presence of deciduous lowland forests in the Banten area during the early Holocene. The establishment of coconut and pine plantations and the severe loss of biodiversity in the last few decennia are also echoed in the pollen record. The effect of the Krakatau eruption was insignificant compared with human impact on vegetation in the Banten area. Copyright © 2004 John Wiley & Sons, Ltd. [source] Fate of epiphytes on phorophytes with different architectural characteristics along the perturbation gradient of Sabal mexicana forests in Veracruz, MexicoJOURNAL OF VEGETATION SCIENCE, Issue 1 2010A. Aguirre Abstract Question: Vascular epiphytes and hemiepiphytes (E/HE) in neotropical forests account for a large fraction of plant richness, but little is known of how the interplay between phorophyte architectural characteristics and habitat perturbation affect communities of E/HE. Location: Sabal mexicana forests in a coastal area of Veracruz, Mexico. Methods: We compared communities of E/HE on phorophytes with different architectural characteristics , the palm S. mexicana and non-palm phorophytes , in three environments: conserved sites, perturbed sites and small regenerated forest fragments. We combined traditional (abundance, species richness, similarity and complementarity indices) and more recent (phylogenetic diversity) metrics to describe the communities of E/HE. Results: Overall, we recorded 924 E/HE individuals (nine families, 16 genera and 21 species). The abundance and species richness of E/HE was higher on palms than on non-palm phorophytes. Abundance-based complementarities between phorophytes and sites were high. We detected clear changes in community structure of E/HE with habitat perturbation, but there were no effects on the phylogenetic diversity of the E/HE community. Palm phorophytes hosted a more phylogenetically diverse community of E/HE than did non-palm phorophytes. Conclusions: Palm phorophytes are key elements supporting the conservation of resilient communities of E/HE in S. mexicana forest. Habitat fragmentation has a strong effect on the structure of the E/HE community in S. mexicana forests. Ferns are the group of epiphytes most severely affected by habitat perturbation, but we detected no significant effect on the phylogenetic diversity of the community. [source] Nutrients, Chlorophyll a and Phytoplankton in the ,skenderun Bay (Northeastern Mediterranean)MARINE ECOLOGY, Issue 2 2002Sevim Polat Abstract. The monthly changes in chlorophyll a, phytoplankton abundance and nutrient concentrations at two stations, one at the inshore and the other at the deep waters of the northern part of ,skenderun Bay, were investigated between 1994,,,1995. The vertical distribution of nutrients and phytoplankton biomass were also studied at the deep station. The concentrations of NO3+NO2 -N, PO4 -P and SiO4 -Si of surface water at both stations were 0.31,,,1.63 µg-at · l -1, 0.08,,,0.60 µg-at · l -1 and 0.50,,,2.7 µg-at · l -1, respectively. The highest concentrations were measured at the inshore station and clear differences were found between the inshore and deep-water stations. Chlorophyll a concentrations ranged from 0.17 to 2.78 µg · l -1 and the highest value was measured in March. At the inshore station, which was affected by land run-off, phytoplankton abundance reached the highest value (21,308 cells · l -1) in October 1995, with a marked dominance of Pseudonitzschia pungens (20,200 cells · l -1). The nutrient and chlorophyll a concentrations at the inshore station were higher than those at the deep station. One reason for this is the land-based nutrient input into the coastal area here. In spite of these effects, the bay is not eutrophicated because of circulation events in the northeastern Mediterranean. [source] Fishing gears involved in entanglements of minke whales (Balaenoptera acutorostrata) in the East Sea of KoreaMARINE MAMMAL SCIENCE, Issue 2 2010Kyung-Jun Song Abstract Entanglement of marine mammals in fishing gear is a global issue. It is considered a significant threat to minke whales (Balaenoptera acutorostrata) in the East Sea of Korea. A total of 214 entanglements of minke whales in this area between 2004 and 2007 were used to investigate types and parts of fishing gears involved in entanglements. The majority of entanglements were mainly caused by three types of fishing gears: set nets, pots, and gill nets (n= 207, 96.7%). Other entanglements were associated with bottom trawls, purse seines, and trawls. A total of 65 entanglements were attributed to the main and branch lines of fishing gears. The most common body part of minke whales which attached to fishing gears was the mouth (n= 63, 30.4%). Most entanglements took place within 10 nmi from land (n= 179, 86.5%), and between 10 and 220 m of water depth. The mean length of entangled minke whales in set nets was significantly smaller than that of whales in pots and gill nets samples (P < 0.001). Also, the mean body length of minke whales that entangled in the coastal area and shallow waters was significantly shorter than that of whales in the offshore area and deep waters (P < 0.001). This information can be used as fundamental data to conserve and manage this population of minke whales in the East Sea of Korea, and also to modify fishing gear to reduce entanglements. Future studies should focus on investigating the impact of these entanglements on the population and the effectiveness of mitigation measures to reduce entanglements of minke whales in this area. [source] Salmon lice infection of wild sea trout and Arctic char in marine and freshwaters: the effects of salmon farmsAQUACULTURE RESEARCH, Issue 12 2001P A Bjørn Abstract The abundance of salmon lice and the physiological effects of infection were examined in two stocks of sympatric sea trout and anadromous Arctic char in northern Norway. One stock feed in a coastal area with extensive salmon farming (exposed locality), while the other feed in a region with little farming activity (unexposed locality). The results showed that the lice infection was significantly higher at the exposed locality, at which the mean intensity of infection peaked in June and July at over 100 and 200 lice larvae per fish respectively. At the exposed locality we also observed a premature return to freshwater of the most heavily infected fish. Such behaviour has previously been interpreted as a response by the fish to reduce the stress caused by the infection and/or to enhance survival. Blood samples taken from sea trout at sea at the exposed locality showed a positive correlation between intensity of parasite infection and an increase in the plasma cortisol, chloride and blood glucose concentrations, while the correlations from sea trout in freshwater were more casual. Several indices pointed towards an excessive mortality of the heaviest infected fish, and 47% of the fish caught in freshwater and 32% of those captured at sea carried lice at intensities above the level that has been shown to induce mortality in laboratory experiments. Furthermore, almost half of all fish from the exposed locality had lice intensities that would probably cause osmoregulatory imbalance. High salmon lice infections may therefore have profound negative effects upon wild populations of sea trout. At the unexposed location, the infection intensities were low, and few fish carried more than 10 lice. These are probably within the normal range of natural infection and such intensities are not expected to affect the stock negatively. [source] Biomass removal by dolphins and fisheries in a Mediterranean Sea coastal area: do dolphins have an ecological impact on fisheries?AQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 5 2010Giovanni Bearzi Abstract 1.Dolphins are often claimed to compete with fisheries, including through removal of substantial biomass. To calculate the biomass removed by fisheries and the degree of resource overlap with dolphins in a coastal area of Greece, estimates of dolphin abundance based on photographic capture,recapture were combined with an assessment of fishing effort and catch. 2.The estimated total biomass consumed annually by local dolphin populations , 15 short-beaked common dolphins and 42 common bottlenose dolphins , was 15.5 and 89.8 tonnes, respectively. The total biomass removed by the local fishing fleet (307 fishing boats) was 3469.2 tonnes, i.e. about 33 times greater than that removed by dolphins. 3.Dolphins removed 2.9% of the total biomass, fisheries 97.1%. Nine purse seiners (representing only 3% of the active fishing fleet) were responsible for 31.9% of biomass removal. Similarity of biomass composition between dolphins and fisheries was expressed by a Pianka index of 0.46 for common dolphins and 0.66 for bottlenose dolphins. 4.Overlap differed according to fishing gear. Common dolphin overlap was higher with purse seiners (0.82), and lower with beach seiners (0.31), bottom trawlers (0.11) and trammel boats (0.06). There was virtually no overlap with longliners (0.02). Bottlenose dolphin overlap was higher with trammel boats (0.89) and bottom trawlers (0.75), and lower with longliners (0.38), purse seiners (0.24) and beach seiners (0.18). There was minimal overlap (0.12) between the two dolphin species. 5.This study suggests that ecological interactions between dolphins and fisheries in this coastal area have minor effects on fisheries. Conversely, prey depletion resulting from overfishing can negatively affect dolphins. Fisheries management measures consistent with national and EU legislation are proposed to ensure sustainability and to protect marine biodiversity. Copyright © 2010 John Wiley & Sons, Ltd. [source] Loss of Ostracoda biodiversity in Western Mediterranean wetlandsAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 3 2008José M. Poquet Abstract 1.The coastal area of Valencia (Spain) in the Western Mediterranean is rich in freshwater and brackish wetlands. These areas are mostly protected for bird conservation but are also highly affected by human impacts. Six shallow lakes located in Ramsar wetland sites of this area were studied in order to assess past and present ostracod biodiversity and relate it to the status of the lakes, taking into consideration the indicator value of these easily fossilizable crustaceans. 2.In all the wetlands studied, ostracod taphocoenoses showed much higher species richness than the corresponding biocoenoses. This is expected from the time accumulative character of the taphocoenosis, but the trend is clearly evident in the most disturbed sites which indicated loss of ostracod diversity owing to human impacts. 3.By considering the ecology of most frequent species, multivariate ordination of both tapho- and biocoenoses showed trends within and between lakes in their limnological status, which were related mainly to water chemistry, and also to temporality and eutrophication to a certain extent. Some lakes have apparently lost most of their past ostracod community owing to an increasing trophic status in some cases and to modifications of the hydrological regime in others. Copyright © 2007 John Wiley & Sons, Ltd. [source] Tropical Storm Gamma and the Mosquitia of eastern Honduras: a little-known story from the 2005 hurricane seasonAREA, Issue 4 2009David M Cochran Jr The 2005 Atlantic hurricane season was unprecedented in terms of storm activity in the United States, Mexico, Central America and Caribbean. Given the impacts of hurricanes Katrina and Rita, the Honduran Mosquitia sparked little attention despite being hit by two hurricanes and a tropical storm in 2005. This article recounts the history of these storms in the Afro-Caribbean community of Batalla, drawing from public weather advisories and testimony of local residents obtained through participatory research. We contextualise this local history with results from the first paleotempestological study undertaken in the Mosquitia to shed light on long-term risk of catastrophic storms in the region and to demonstrate the value of integrating these two research approaches. Our findings contribute to recent ethnographic research on hazards by describing how a coastal people understand and respond to tropical cyclones and how landscape change influences the vulnerability of a coastal area. Although residents have not witnessed a storm as intense as those documented in the paleotempestological record, their knowledge and perceptions show how tropical cyclones can be disasters while leaving behind no sedimentary records. The paleotempestological evidence, however, reminds us that catastrophic hurricanes have struck the Mosquitia in the past and will do so again in the future. Understanding the interactions between contemporary human perceptions and responses and long-term hurricane risk provides insight for emergency managers and local stakeholders to better prepare for such a catastrophic event. [source] Influence of assimilated SST on regional atmospheric simulation: A case of a cold-air outbreak over the Japan SeaATMOSPHERIC SCIENCE LETTERS, Issue 1 2008Masaru Yamamoto Abstract Sea surface temperature (SST) assimilated using an ocean circulation model is used for the atmospheric simulation of a cold-air outbreak over the Japan Sea. The upward surface-turbulent heat fluxes are significantly influenced by the high-resolution SST structure resulting from mesoscale oceanic eddies. A strong deceleration of the outbreak due to local convective activity arises in a coastal area when using the assimilated SST data, in good agreement with observations; however, this feature is not observed when using the interpolated SST. In general, the use of assimilated temperature does improve regional atmospheric simulations. Copyright © 2008 Royal Meteorological Society [source] Diversity and seasonal succession of coastal mosquitoes (Diptera: Culicidae) in the northern Adelaide region of South AustraliaAUSTRALIAN JOURNAL OF ENTOMOLOGY, Issue 2 2009Craig R Williams Abstract Northern coastal suburbs in metropolitan Adelaide, South Australia are often subject to extreme levels of mosquito nuisance biting. The diversity and seasonality of the mosquito community in the coastal area of northern Adelaide was investigated over 7 years (2000,2007) in the suburb of Globe Derby Park, which is adjacent to both mangrove and samphire swamps. Eight species were identified from adult mosquito collections, with the salt marsh mosquitoes Aedes camptorhynchus (Thomson) (55.7%) and Ae. vigilax (Skuse) (29.5%) most abundant. These two species display seasonal succession, with the former most abundant in spring and early summer, giving way to the latter in mid-late summer and autumn. Logistic regression showed that Ae. camptorhynchus abundance spikes were associated with lower temperatures, higher rainfall and increasing day length (r2 = 0.38). Aedes vigilax abundance spikes were associated with higher temperatures and decreasing day length (r2 = 0.52). The description of such temporal succession in salt marsh mosquitoes in southern Australia is novel. The analysis presented might therefore lead to the development of mosquito nuisance predictive tools and novel mosquito management strategies. [source] Late Quaternary history of the Kap Mackenzie area, northeast GreenlandBOREAS, Issue 3 2010BERND WAGNER Wagner, B., Bennike, O., Cremer, H. & Klug, M. 2010: Late Quaternary history of the Kap Mackenzie area, northeast Greenland. Boreas, Vol. 39, pp. 492,504. 10.1111/j.1502-3885.2010.00148.x. ISSN 0300-9483. The Kap Mackenzie area on the outer coast of northeast Greenland was glaciated during the last glacial stage, and pre-Holocene shell material was brought to the area. Dating of marine shells indicates that deglaciation occurred in the earliest Holocene, before 10 800 cal. a BP. The marine limit is around 53 m a.s.l. In the wake of the deglaciation, a glaciomarine fauna characterized the area, but after c. one millennium a more species-rich marine fauna took over. This fauna included Mytilus edulis and Mysella sovaliki, which do not live in the region at present; the latter is new to the Holocene fauna of northeast Greenland. The oldest M. edulis sample is dated to c. 9500 cal. a BP, which is the earliest date for the species from the region and indicates that the Holocene thermal maximum began earlier in the region than previously documented. This is supported by driftwood dated to c. 9650 cal. a BP, which is the earliest driftwood date so far from northeastern Greenland and implies that the coastal area was at least partly free of sea ice in summer. As indicated by former studies, the Storegga tsunami hit the Kap Mackenzie area at c. 8100 cal. a BP. Loon Lake, at 18 m a.s.l., was isolated from the sea at c. 6200 cal. a BP, which is distinctly later than expected from existing relative sea-level curves for the region. [source] Effects of Coastal Lighting on Foraging Behaviorof Beach MiceCONSERVATION BIOLOGY, Issue 5 2004BRITTANY L. BIRD comportamiento de forrajeo; iluminación artificial; polución por luz; ratones de playa (Peromyscus polionotus leucocephalus) Abstract:,Introduction of artificial light into wildlife habitat represents a rapidly expanding form of human encroachment, particularly in coastal systems. Light pollution alters the behavior of sea turtles during nesting; therefore, long-wavelength lights,low-pressure sodium vapor and bug lights,that minimize impacts on turtles are required for beach lighting in Florida (U.S.A.). We investigated the effects of these two kinds of lights on the foraging behavior of Santa Rosa beach mice ( Peromyscus polionotus leucocephalus). We compared patch use and giving-up densities of mice for experimental food patches established along a gradient of artificial light in the field. Mice exploited fewer food patches near both types of artificial light than in areas with little light and harvested fewer seeds within patches near bug lights. Our results show that artificial light affects the behavior of terrestrial species in coastal areas and that light pollution deserves greater consideration in conservation planning. Resumen:,La introducción de luz artificial al hábitat de vida silvestre representa una forma de intrusión humana que se expande rápidamente, particularmente en sistemas costeros. Durante la anidación, la polución por luz altera el comportamiento de tortugas marinas; por tanto, para la iluminación de playas en Florida (E. U. A) se requieren luces de longitud de onda larga , luces de vapor de sodio de baja presión y contra insectos , que minimizan impactos sobre las tortugas. Investigamos los efectos de estos dos tipos de luces sobre el comportamiento de forrajeo de ratones de playa de Santa Rosa ( Peromyscus polionotus leucocephalus). Comparamos el uso de parches y las densidades de rendición de ratones en parches alimenticios experimentales establecidos a lo largo de un gradiente de luz artificial en el campo. Los ratones utilizaron menos parches de forrajeo cercanos a ambos tipos de luz artificial que en áreas con poca iluminación y cosecharon menos semillas en parches cercanos a luces contra insectos. Nuestros resultados muestran que la luz artificial afecta el comportamiento de especies terrestres en áreas costeras y que la polución por luz merece mayor consideración en la planificación de la conservación. [source] Reassessing the value of nursery areas to shark conservation and managementCONSERVATION LETTERS, Issue 2 2009Michael John Kinney Abstract Concern over declining shark populations has led to an intense interest in their conservation and management. Due to the difficulties involved in managing adult sharks, focus has been placed on young juvenile and neonate age classes that inhabit discrete inshore nursery areas. However, past confusion over what qualifies as a nursery habitat has led to the identification of vast coastal areas as nurseries, making conservation unfeasible. With the establishment of more discerning criteria for nursery area identification such concerns have been somewhat alleviated, but while effort has been put into defining, identifying, mapping, and in some cases protecting nursery areas, little attention has been paid to the practical value of nurseries for the recovery of exploited shark populations. Often neonate and young juveniles are considered the most critical age classes in terms of population stability/recovery, but evidence is mounting that suggests life stages outside the nursery may be more important in this regard. While nursery area protection should remain a component in shark management strategies it will be critical to link early life stage conservation with management strategies that encompass older individuals residing outside nurseries if effective management is to be achieved. [source] Elevation of gene expression for salmon gonadotropin-releasing hormone in discrete brain loci of prespawning chum salmon during upstream migrationDEVELOPMENTAL NEUROBIOLOGY, Issue 2 2005Takeshi Onuma Abstract Our previous studies suggested that salmon gonadotropin-releasing hormone (sGnRH) neurons regulate both final maturation and migratory behavior in homing salmonids. Activation of sGnRH neurons can occur during upstream migration. We therefore examined expression of genes encoding the precursors of sGnRH, sGnRH-I, and sGnRH-II, in discrete forebrain loci of prespawning chum salmon, Oncorhynchus keta. Fish were captured from 1997 through 1999 along their homing pathway: coastal areas, a midway of the river, 4 km downstream of the natal hatchery, and the hatchery. Amounts of sGnRH mRNAs in fresh frozen sections including the olfactory bulb (OB), terminal nerve (TN), ventral telencephalon (VT), nucleus preopticus parvocellularis anterioris (PPa), and nucleus preopticus magnocellularis (PM) were determined by quantitative real-time polymerase chain reactions. The amounts of sGnRH-II mRNA were higher than those of sGnRH-I mRNA, while they showed similar changes during upstream migration. In the OB and TN, the amounts of sGnRH mRNAs elevated from the coast to the natal hatchery. In the VT and PPa, they elevated along with the progress of final maturation. Such elevation was also observed in the rostroventral, middle, and dorsocaudal parts of the PM. The amounts of gonadotropin II, and somatolactin mRNAs in the pituitary also increased consistently with the elevation of gene expression for sGnRH. These results, in combination with lines of previous evidence, indicate that sGnRH neurons are activated in almost all the forebrain loci during the last phases of spawning migration, resulting in coordination of final gonadal maturation and migratory behavior to the spawning ground. © 2005 Wiley Periodicals, Inc. J Neurobiol, 2005 [source] Past distribution and ecology of the cork oak (Quercus suber) in the Iberian Peninsula: a pollen-analytical approachDIVERSITY AND DISTRIBUTIONS, Issue 1 2000J. S. Carrión Abstract., This study presents pollen-analytical data from continental and offshore Iberian Peninsula sites that include pollen curves of Quercus suber, to provide information on the past distribution and ecology of the cork oak (Q. suber). Results centre on a new pollen record of Navarrés (Valencia, eastern Spain), which shows that the cork oak survived regionally during the Upper Pleistocene and was important during a mid-Holocene replacement of a local pine forest by Quercus -dominated communities. This phenomenon appears linked to the recurrence of fire and reinforces the value of the cork oak for reforestation programmes in fire-prone areas. In addition to Navarrés, other Late Quaternary pollen sequences (Sobrestany, Casablanca-Almenara, Padul, SU 8103, SU8113, 8057B) suggest last glacial survival of the cork oak in southern and coastal areas of the Peninsula and North Africa. Important developments also occur from the Late Glacial to the middle Holocene, not only in the west but also in the eastern Peninsula. It is suggested that, in the absence of human influence, Q. suber would develop in non-monospecific forests, sharing the arboreal stratum both with other sclerophyllous and deciduous Quercus and Pinus species. 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