GPS linked photos of benthic cover transect surveys in Heron Reef

Underwater photo-transect surveys were conducted on September 23-27, 2007 at different sections of the reef flat, reef crest and reef slope in Heron Reef. This survey was done by swimming along pre-defined transect sites and taking a picture of the bottom substrate parallel to the bottom at constant vertical distance (30cm) every two to three metres. A total of 3,586 benthic photos were taken. A floating GPS setup connected to the swimmer/diver by a line enabled recording of coordinates of transect surveys. Approximation of the coordinates for each benthic photo was based on the photo timestamp and GPS coordinate time stamp, using GPS Photo Link Software. Coordinates of each photo were interpolated by finding the the gps coordinates that were logged at a set time before and after the photo was captured. The output of this process was an ArcMap point shapefile, a Google Earth KML file and a thumbnail of each benthic photo taken. The data in the ArcMap shapefile and in the Google Earth KML file consisted of the approximated coordinate of each benthic photo taken during the survey. Using the GPS Photo Link extension within the ArcMap environment, opening the ArcMap shapefile will enable thumbnail to be displayed on the associated benthic cover photo whenever hovering with the mouse over a point on the transect. By downloading the GPSPhotoLink software from the www.geospatialexperts.com, and installing it as a trial version the ArcMap exstension will be installed in the ArcMap environment.

Georeferenced standardized apparent wave power along the coastline of Cabrera National Park for analysis of essential habitats of littoral species

Wind- induced exposure is one of the major forces shaping the geomorphology and biota in coastal areas. The effect of wave exposure on littoral biota is well known in marine environments (Ekebon et al., 2003; Burrows et al., 2008). In the Cabrera Archipelago National Park wave exposure has demostrated to have an effect on the spatial distribution of different stages of E.marginatus (Alvarez et al., 2010). Standarized average wave exposures during 2008 along the Cabrera Archipelago National park coast line were calculated to be applied in studies of littoral species distribution within the archipelago. Average wave exposure (or apparent wave power) was calculated for points located 50 m equidistant on the coastline following the EXA methodology (EXposure estimates for fragmented Archipelagos) (Ekebon et al., 2003). The average wave exposures were standardized from 1 to 100 (minimum and maximum in the area), showing coastal areas with different levels of mea wave exposure during the year. Input wind data (direction and intensity) from 2008 was registered at the Cabrera mooring located north of Cabrera Archipelago. Data were provided by IMEDEA (CSIC-UIB, TMMOS http://www.imedea.uib-csic.es/tmoos/boyas/). This cartography has been developed under the framework of the project EPIMHAR, funded by the National Park's Network (Spanish Ministry of Environment, Maritime and Rural Affairs, reference: 012/2007 ). Part of this work has been developed under the research programs funded by "Fons de Garantia Agrària i Pesquera de les Illes Balears (FOGAIBA)".

The benthic foraminiferal community in a naturally CO2-rich coastal habitat of the southwestern Baltic Sea

It is expected that the calcification of foraminifera will be negatively affected by the ongoing acidification of the oceans. Compared to the open oceans, these organisms are subjected to much more adverse carbonate system conditions in coastal and estuarine environments such as the southwestern Baltic Sea, where benthic foraminifera are abundant. This study documents the seasonal changes of carbonate chemistry and the ensuing response of the foraminiferal community with bi-monthly resolution in Flensburg Fjord. In comparison to the surface pCO2, which is close to equilibrium with the atmosphere, we observed large seasonal fluctuations of pCO2 in the bottom and sediment pore waters. The sediment pore water pCO2 was constantly high during the entire year ranging from 1244 to 3324 µatm. Nevertheless, in contrast to the bottom water, sediment pore water was slightly supersaturated with respect to calcite as a consequence of higher alkalinity (AT) for most of the year. Foraminiferal assemblages were dominated by two calcareous species, Ammonia aomoriensis and Elphidium incertum, and the agglutinated Ammotium cassis. The one-year cycle was characterised by seasonal community shifts. Our results revealed that there is no dynamic response of foraminiferal population density and diversity to elevated sediment pore water pCO2. Surprisingly, the fluctuations of sediment pore water undersaturation (Omega calc) co-vary with the population densities of living Ammonia aomoriensis. Further, we observed that most of the tests of living calcifying foraminifera were intact. Only Ammonia aomorienis showed dissolution and recalcification structures on the tests, especially at undersaturated conditions. Therefore, the benthic community is subjected to high pCO2 and tolerates elevated levels as long as sediment pore water remains supersaturated. Model calculations inferred that increasing atmospheric CO2 concentrations will finally lead to a perennial undersaturation in sediment pore waters. Whereas benthic foraminifera indeed may cope with a high sediment pore water pCO2, the steady undersaturation of sediment pore waters would likely cause a significant higher mortality of the dominating Ammonia aomoriensis. This shift may eventually lead to changes in the benthic foraminiferal communities in Flensburg Fjord, as well as in other regions experiencing naturally undersaturated Omega calc levels.

Modelling impacts and recovery in benthic communities exposed to localised high CO2

Regulations pertaining to carbon dioxide capture with offshore storage (CCS) require an understanding of the potential localised environmental impacts and demonstrably suitable monitoring practices. This study uses a marine ecosystem model to examine a comprehensive range of hypothetical CO2 leakage scenarios, quantifying both impact and recovery time within the benthic system. Whilst significant mortalities and long recovery times were projected for the larger and longer term scenarios, shorter-term or low level exposures lead to reduced projected impacts. This suggests that efficient monitoring and leak mitigation strategies, coupled with appropriate selection of storage sites can effectively limit concerns regarding localised environmental impacts from CCS. The feedbacks and interactions between physiological and ecological responses simulated reveal that benthic responses to CO2 leakage could be complex. This type of modelling investigation can aid the understanding of impact potential, the role of benthic community recovery and inform the design of baseline and monitoring surveys.

Modelling impacts and recovery in benthic communities exposed to localised high CO2

Regulations pertaining to carbon dioxide capture with offshore storage (CCS) require an understanding of the potential localised environmental impacts and demonstrably suitable monitoring practices. This study uses a marine ecosystem model to examine a comprehensive range of hypothetical CO2 leakage scenarios, quantifying both impact and recovery time within the benthic system. Whilst significant mortalities and long recovery times were projected for the larger and longer term scenarios, shorter-term or low level exposures lead to reduced projected impacts. This suggests that efficient monitoring and leak mitigation strategies, coupled with appropriate selection of storage sites can effectively limit concerns regarding localised environmental impacts from CCS. The feedbacks and interactions between physiological and ecological responses simulated reveal that benthic responses to CO2 leakage could be complex. This type of modelling investigation can aid the understanding of impact potential, the role of benthic community recovery and inform the design of baseline and monitoring surveys.

An investigation on benthic macro-invertebrates species diversity as bio-indicators of environmental health in Bahrekan Bay

The purpose of this study was to evaluate benthic macro-invertebrates species diversity as bio-indicators of environmental health in Bahrekan bay (in the Northwest of Persian gulf). Seasonal sediments sampling along 5 transects, 15 stations at 4 replicates (3 replicates for macrobenthos and 1 replicate for sediment analysis) was done from November 2008 to August 2009 by 0.025 m2 Van Veen grab sampler. Physical and chemical parameters of water, grain size analysis, %TOM and Ni and Va concentrations of sediments were assessed through four seasons. Macrobenthic communities after staining and sorting, using stereomicroscope have been identified. Their density in every station and every season calculated. For using of AMBI index, identified macrobenthos according to their sensitivity to stressors and pollutants, categorized into 5 ecological groups and for using of Bentix index categorized into 3 ecological groups. The diversity indices and indicators that showing ecological status were calculated. Also, the differences between physiochemical parameters of sea water, sediments TOM% and grain size, diversity indices in stations and seasons were recorded (P=0.05). The correlation coefficient determined for all parameters. According to the results of grain size analysis, bottom grain size categorized as clay. Highest percent of TOM was belong to autumn (36.39±.075) and lowest was belong to summer (19.01±0.51). Also there was positive correlation (p=0.01) between %TOM and %Clay that showing sediments with lowest size containing highest amounts of organic matters. Ni concentrations in sediments (87.80±21.25)mg/kg showed the amounts over than standards levels but Va concentrations in sediments (53.54±17.60)mg/kg showed the amounts lower than standards level. The highest density of macrobenthos was recorded for summer (8254±485) N/m2 and the lowest density was recorded for spring (3775±172)N/m2. The highest annual density was belong to mollusca (81%) and then polycheates (13%), Others (4%) and crustaceae (2%). The highest diversity was recorded for winter (Simpson index: 0.13±0.01, H':3.47±0.06) and the lowest diversity recorded for autumn (Simpson index: 0.16±0.01, H':3.17±0.06). in all stations, the highest amount of Shanon index was belong to T2S3 station in summer (4.11± 0.32) and the lowest amount was belong to T1S1 station in autumn (2.42± 0.41). The annual mean of Simpson diversity index: (0.15 ±0.04) and Shanon diversity index (3.36±0.03), illustrated that macrobenthos in Bahrekan bay have a good variation. The results of Brilluin and N1 (Number of equally common species) indices confirm the results of Simpson index. For study on the regions that diversity has a little difference between stations, with use of Ni index, the degree of differences could be better ono recognizable. According to the results of AMBI index in all seasons (autumn: 0.46±0.03; summer: 0.22±0.01; annual mean:0.31±0.01) and standards (0.0

Nutrient-induced perturbations to delta C-13 and delta N-15 in symbiotic dinoilagellates and their coral hosts

Inorganic nutrients play a critical role in determining benthic community structure in tropical seas. This study examined the impact of adding inorganic nutrients (ammonium and phosphate) on the isotopic composition of 2 reef-building corals, Pocillopora damicornis and Heliofungia actiniformis, on the southern Great Barrier Reef. The addition of elevated nutrients to patch reefs that pond at low tide did not perturb the C:N ratio of either species or their symbiotic dinoflagellates. The C:N ratios were significantly higher in material extracted from the skeleton (14.8 +/- 1.50 and 10.8 +/- 1.42) than either host (7.6 +/- 0.87 and 6.0 +/- 0.71) or symbiotic dinoflagellates (5.7 +/- 0.48 and 6.9 +/- 0.66) (P. damicornis and H. actiniformis respectively; 95 confidence intervals). The ratio of acquired N to background N suggests that the added dissolved inorganic nitrogen (DIN) accounted for 50 to 100% of total nitrogen within the tissues of P. damicornis and H. actiniformis at the end of the experiment. The addition of the isotopically depleted nutrients (delta(15) N = 0parts per thousand) to patch reefs significantly decreased delta(15)N from control values of between 3 and 4 to values to below 1 in the case of all compartments, while delta(13)C values were relatively unresponsive to nutrient treatments. These findings suggest that coral delta(15)N has the potential to provide a historical record of the delta(15)N of dissolved nitrogen surrounding reef-building corals and their symbiotic dinoflagellates.

Dynamic ecosystems under anthropogenic stress : how does macrotidal sandy fauna respond to green tides?

Highly dynamic systems, often considered as resilient systems, are characterised by abiotic and biotic processes under continuous and strong changes in space and time. Because of this variability, the detection of overlapping anthropogenic stress is challenging. Coastal areas harbour dynamic ecosystems in the form of open sandy beaches, which cover the vast majority of the world’s ice-free coastline. These ecosystems are currently threatened by increasing human-induced pressure, among which mass-development of opportunistic macroalgae (mainly composed of Chlorophyta, so called green tides), resulting from the eutrophication of coastal waters. The ecological impact of opportunistic macroalgal blooms (green tides, and blooms formed by other opportunistic taxa), has long been evaluated within sheltered and non-tidal ecosystems. Little is known, however, on how more dynamic ecosystems, such as open macrotidal sandy beaches, respond to such stress. This thesis assesses the effects of anthropogenic stress on the structure and the functioning of highly dynamic ecosystems using sandy beaches impacted by green tides as a study case. The thesis is based on four field studies, which analyse natural sandy sediment benthic community dynamics over several temporal (from month to multi-year) and spatial (from local to regional) scales. In this thesis, I report long-lasting responses of sandy beach benthic invertebrate communities to green tides, across thousands of kilometres and over seven years; and highlight more pronounced responses of zoobenthos living in exposed sandy beaches compared to semi-exposed sands. Within exposed sandy sediments, and across a vertical scale (from inshore to nearshore sandy habitats), I also demonstrate that the effects of the presence of algal mats on intertidal benthic invertebrate communities is more pronounced than that on subtidal benthic invertebrate assemblages, but also than on flatfish communities. Focussing on small-scale variations in the most affected faunal group (i.e. benthic invertebrates living at low shore), this thesis reveals a decrease in overall beta-diversity along a eutrophication-gradient manifested in the form of green tides, as well as the increasing importance of biological variables in explaining ecological variability of sandy beach macrobenthic assemblages along the same gradient. To illustrate the processes associated with the structural shifts observed where green tides occurred, I investigated the effects of high biomasses of opportunistic macroalgae (Ulva spp.) on the trophic structure and functioning of sandy beaches. This work reveals a progressive simplification of sandy beach food web structure and a modification of energy pathways over time, through direct and indirect effects of Ulva mats on several trophic levels. Through this thesis I demonstrate that highly dynamic systems respond differently (e.g. shift in δ13C, not in δ15N) and more subtly (e.g. no mass-mortality in benthos was found) to anthropogenic stress compared to what has been previously shown within more sheltered and non-tidal systems. Obtaining these results would not have been possible without the approach used through this work; I thus present a framework coupling field investigations with analytical approaches to describe shifts in highly variable ecosystems under human-induced stress.

Effect of industrial pollution on the benthic communities of a tropical estuary

Cochin backwaters, a tropical barbuilt estuary is well known for its prawn, molluscan and demersal fisheries. Also it formed the dumping area for sewage,235 retting of husks and discharge of effluents from industries located on either side of it. As a result the fishery is being gradually dwindled year after year due to the lowering of the water quality. The effect of industrial polution on the benthic community of this tropical estuary was worked out. An area extending over 21 km from the mouth of the estuary to upstream of industrial belt was selected. Temporal and spatial variations of 16 environmental parameters at 9 stations along the area were monitored monthly during 1981. Benthic fauna of these 9 stations consisted of amphipods , polychaetes, isopods, tanaidaceans, molluscs and other crustaceans (Decapods, Acetes, Alpheids, Balanus, insect larvae, chironomid larvae, cumacea and some fresh water forms ). Apart from these, sea anemone, flat worms, nematodes, sipunculoids, echinoderms and fishes were also encountered. 75 species belonging to 31 faunal groups were identified. Of these 31 groups, amphipods, polychaedes, isopods, tanaidaceans and molluscs were numerically abundant. Rest of the 26 groups (including 13 riverine forms) were found less significant due to their rare occurrence/low numerical abundance. Polychaetes and molluscs were the only major groups present at all the stations.

The heterogeneity of wooded-agricultural landscape mosaics influences woodland bird community assemblages

Context Landscape heterogeneity (the composition and configuration of different landcover types) plays a key role in shaping woodland bird assemblages in wooded-agricultural mosaics. Understanding how species respond to landscape factors could contribute to preventing further decline of woodland bird populations. Objective To investigate how woodland birds with different species traits respond to landscape heterogeneity, and to identify whether specific landcover types are important for maintaining diverse populations in wooded-agricultural environments. Methods Birds were sampled from woodlands in 58 2 x 2 km tetrads across southern Britain. Landscape heterogeneity was quantified for each tetrad. Bird assemblage response was determined using redundancy analysis combined with variation partitioning and response trait analyses. Results For woodland bird assemblages, the independent explanatory importance of landscape composition and landscape configuration variables were closely interrelated. When considered simultaneously during variation partitioning, the community response was better represented by compositional variables. Different species responded to different landscape features and this could be explained by traits relating to woodland association, foraging strata and nest location. Ubiquitous, generalist species, many of which were hole-nesters or ground foragers, correlated positively with urban landcover while specialists of broadleaved woodland avoided landscapes containing urban areas. Species typical of coniferous woodland correlated with large conifer plantations. Conclusions At the 2 x 2 km scale, there was evidence that the availability of resources provided by proximate landcover types was highly important for shaping woodland bird assemblages. Further research to disentangle the effects of composition and configuration at different spatial scales is advocated.

Controlling factors of benthic macroinvertebrates distribution in a small tropical pond, lateral to the Paranapanema River (São Paulo, Brazil).

The aim of the present study was to examine the benthic fauna in a marginal pond lateral to the Paranapanema River and to identify the main controlling factors of its distribution. Considering the small size of the lacustrine ecosystem, we expected that seasonal variations of the benthic community attributes are more important than spatial variations; Methods: Two samplings, one in March and another in August, were carried out at nine sites in the pond. Sediment samples were obtained through a Van Veen grab for invertebrate sorting, granulometric analysis, and for quantification of organic matter in sediment. Other abiotic factors were measured, such as water transparency, dissolved oxygen, pH, electric conductivity, temperature, and depth of sediment sampling sites. Regarding the comparative analysis at spatial scale, no significant variations in density of the benthic invertebrate community were found. Results: In relation to the studied abiotic factors, only depth presented significant differences among sampling sites; All the measured environmental parameters presented significant differences among sampling months, except depth and the physical and chemical characteristics of the sediment. The abundance of Chaoboridae and Chironomidae was the unique attribute with a significant difference in comparing the two months. A higher abundance of taxa occurred in August, especially for Oligochaeta, Nematoda, Chaoboridae, and Chironomidae; Conclusions: Because of the low structural complexity of the studied pond, we concluded that the changes in benthic macroinvertebrate community attributes were mainly due to seasonal effects.

Admiralty Bay Benthos Diversity-A census of a complex polar ecosystem

A thorough census of Admiralty Bay benthic biodiversity was completed through the synthesis of data, acquired from more than 30 years of observations. Most of the available records arise from successive Polish and Brazilian Antarctic expeditions organized since 1977 and 1982, respectively, but also include new data from joint collecting efforts during the International Polar Year (2007-2009). Geological and hydrological characteristics of Admiralty Bay and a comprehensive species checklist with detailed data on the distribution and nature of the benthic communities are provided. Approximately 1300 species of benthic organisms (excluding bacteria, fungi and parasites) were recorded from the bay`s entire depth range (0-500 m). Generalized classifications and the descriptions of soft-bottom and hard-bottom invertebrate communities are presented. A time-series analysis showed seasonal and interannual changes in the shallow benthic communities, likely to be related to ice formation and ice melt within the bay. As one of the best studied regions in the maritime Antarctic Admiralty Bay represents a legacy site, where continued, systematically integrated data sampling can evaluate the effects of climate change on marine life. Both high species richness and high assemblage diversity of the Admiralty Bay shelf benthic community have been documented against the background of habitat heterogeneity. (C) 2010 Elsevier Ltd. All rights reserved.

Evaluating gillnetting protocols to characterize lacustrine fish communities

Ecological research and monitoring of lacustrine ecosystems often requires a whole-lake assessment of fish communities. Gillnet sampling offers an efficient means of estimating abundance, biomass and fish community composition. However the choice of gillnet sampling protocol may influence lake characterization via physical properties of the nets and allocation of sampling effort between littoral, benthic and pelagic habitats. This paper compares two commonly used, whole-lake sampling protocols applied across 17 prealpine, subalpine and alpine European lakes ranging widely in size, depth and altitude to determine their relative strength for research and management applications. Effort-corrected estimates of abundance, biomass and species richness were correlated between the protocols and both distinguished the trout-dominated alpine communities from subalpine and prealpine lakes dominated by whitefish and perch. A considerable amount of variance remained unexplained between the two protocols however, which seemed to correspond with differences in the proportion of effort among benthic and pelagic habitats. We suggest that both the European standard (CEN) and vertical (VERT) netting protocols are suitable for assessing ecological status and monitoring changes in lake fish communities through time. However the details of each protocol should be kept in mind when comparing fish communities between lakes. Mesh sizes used in CEN nets produce a more even size frequency distribution, suggesting that this protocol is most appropriate for assessing size structure of fish assemblages. The high proportion of netting effort in benthic habitats shallower than 70 m depth under the CEN protocol means that, particularly in larger lakes, outcomes will be disproportionately influenced by the ecological condition of this habitat. The VERT protocol presumably provides a more accurate estimate of whole-lake CPUE and community composition because effort, in terms of net area, is more evenly distributed across the entire volume of the lake. This is particularly important in large and deep lakes where pelagic habitats occupy a high proportion of the lake volume.

High-resolution in situ oxygen microprofiles, porewater and solid phase geochemistry from the Crimean shelf (Black Sea) from Maria S. Merian cruise MSM15/1

The outer western Crimean shelf of the Black Sea is a natural laboratory to investigate effects of stable oxic versus varying hypoxic conditions on seafloor biogeochemical processes and benthic community structure. Bottom-water oxygen concentrations ranged from normoxic (175 µmol O2/L) and hypoxic (< 63 µmol O2/L) or even anoxic/sulfidic conditions within a few kilometers' distance. Variations in oxygen concentrations between 160 and 10 µmol/L even occurred within hours close to the chemocline at 134 m water depth. Total oxygen uptake, including diffusive as well as fauna-mediated oxygen consumption, decreased from 15 mmol/m**2/d on average in the oxic zone, to 7 mmol/m**2/d on average in the hypoxic zone, correlating with changes in macrobenthos composition. Benthic diffusive oxygen uptake rates, comprising respiration of microorganisms and small meiofauna, were similar in oxic and hypoxic zones (on average 4.5 mmol/m**2/d), but declined to 1.3 mmol/m**2/d in bottom waters with oxygen concentrations below 20 µmol/L. Measurements and modeling of porewater profiles indicated that reoxidation of reduced compounds played only a minor role in diffusive oxygen uptake under the different oxygen conditions, leaving the major fraction to aerobic degradation of organic carbon. Remineralization efficiency decreased from nearly 100 % in the oxic zone, to 50 % in the oxic-hypoxic zone, to 10 % in the hypoxic-anoxic zone. Overall, the faunal remineralization rate was more important, but also more influenced by fluctuating oxygen concentrations, than microbial and geochemical oxidation processes.

Growth increments of the recent brachiopod Magellania venosa mechanically marked in Paso Comau and Comau Fjord, Chile, 2011/2012

Magellania venosa, the largest recent brachiopod, occurs in clusters and banks in population densities of up to 416 ind/m**2 in Comau Fjord, Northern Chilean fjord region. Below 15 m, it co-occurs with the mytilid Aulacomya atra and it dominates the benthic community below 20 m. To determine the question of why M. venosa is a successful competitor, the in situ growth rate of the brachiopod was studied and its overall growth performance compared with that of other brachiopods and mussels. The growth in length was measured between February 2011 and March 2012 after mechanical tagging and calcein staining. Settlement and juvenile growth were determined from recruitment tiles installed in 2009 and from subsequent photocensus. Growth of M. venosa is best described by the general von Bertalanffy growth function, with a maximum shell length (Linf) of 71.53 mm and a Brody growth constant (K) of 0.336/year. The overall growth performance (OGP index = 5.1) is the highest recorded for a rynchonelliform brachiopod and in the range of that for Mytilus chilensis (4.8-5.27), but lower than that of A. atra (5.74). The maximal individual production (PInd) is 0.29 g AFDM/ind/year at 42 mm shell length and annual production ranges from 1.28 to 89.25 g AFDM/year/m**2 (1-57% of that of A. atra in the respective fjords). The high shell growth rate of M. venosa, together with its high overall growth performance may explain the locally high population density of this brachiopod in Comau Fjord. However, the production per biomass of the population (P/B-ratio) is low (0.535) and M. venosa may play only a minor role in the food chain. Settling dynamics indicates that M. venosa is a pioneer species with low juvenile mortality. The coexistence of the brachiopod and bivalve suggests that brachiopod survival is affected by neither the presence of potential brachiopod predators nor that of space competitors (i.e. mytilids).