Distribution of Organic Matter, Iron, Mangenese in SurfaceSediments in the Nansha Islands Sea Area, South China Sea

Concentrations of organic matter, iron and manganese in the deep sea surface sediments in the Nansha Islands sea area, South China Sea are measured, Horizontal and vertical distributions of iron and manganese are discussed. The vertical distribution of iron and manganese in the sediments results from reduction, diffusion, and redeposition of manganese (or iron) oxide and hydroxide in the sediment. There are the maxima of iron and manganese in solid phase in the top of the sediment, which is caused by the penetration of O2 and the upward flux of Mn^2 ( or Fe^2 ). Manganese bacteria play a very important role in the cycle of solid-phase iron and manganese in the ocean environment. Manganese bacteria oxidize Mn^2 ( or Fe^2 ) in dissolved state to Mn^4 ( or Fe^3 ) in oxidized state under the aerobic condition, whereas they reduce iron and manganese in anaerobic conditions.     

Fisheries management in Central Maluku,Indonesia, 1997–98

Interviews with government staff responsible for fisheries management in Maluku, Indonesia in 1997–98 revealed problems in capacity, and an emphasis on economic development rather than management. The traditional institutions which persisted in some villages to regulate the access and withdrawal rights over key inshore species, were also disjunct from government departments. The period following December 1998 is marked by political upheaval, legislative change that (in theory) decentralized governance over inshore waters, and violent unrest centered in Maluku. All these make the data collected in 1997–98 of historical interest. The state of fisheries management in Maluku remains undefined, pending further legislative reform and peace that will allow governments and communities to negotiate and implement new institutional arrangements.     

Distribution of moretene, sterere, fernene, hopene and dienoic carboxylic acid in marine sediments in sea area of the Southern Ocean

The soluble organic matters were extracted from marine sediments in the sea area of Southern Ocean by using organic solvents. The hydrocarbon and carboxylic acid fractions were separated with the thin layer chromatography. The organic compounds of 170(H), 21α(H)- bishomomoretene, cholest - 5 - ene, 24 - methyl - cholestene, 24 - ethylcholestene, hop-17(21)-ene, neohop - 13(18)-ene, fern-8-ene, fern-7-ene, 170(H), 210 (H) - hop - 22(29)-ene (diplotene), steranes, β, β-hopanes C29 -C31 and unsaturated carboxylic acids C18:2Δ9.12 , C18:1Δ9,C18:1Δ11 , have been identi-fied in the hydrocarbon and carboxylic acid fractions by means of gas chromatography and gas chromatography - mass spec-trometry - data system. The distributions of 3, a - bishomomoretene, β,β- hopene and β,β- hopane are characteristic of immature organic matter. The sterane, C29 20S/20R epimer ratio 0. 6 indicate that the organic matter had experienced a thermal evolution in the early sedimentation. The unsaturated fatty acids espec     

From community-based to co-management: Improvement or deterioration in fisheries governance in the Cherai Poyil fishery in the Cochin Estuary,Kerala, India?

During the last 50 years, several different forms of fisheries governance have been tried and failed in the Cochin Estuary, Kerala, India. The latest shift has been from a community-based system to a co-management system, and this paper evaluates the current system in the light of the theoretical debate over the respective merits of community-based management and co-management. The paper is based on documentary material and data from interviews carried out during fieldwork in 2004, from which it concludes that provided the co-management system incorporates community principles within it, it will be an effective form of fisheries governance.     

Creeping in? Neoliberalism,indigenous realities and tropical rock lobster (kaiar) management in Torres Strait,Australia

This article examines current neoliberal forces in the Torres Strait tropical rock lobster (TRL) fishery and their likely impacts on the lives of indigenous Islanders. It describes how neoliberal principles of market governance, commodification of natural resources, profit maximization, individualization and property rights are at odds with Islander rights, values, sense of place, and institutions of knowledge, tenure and practice. It argues that proposed fisheries measures based on neoliberal imperatives could cause important conflicts and create high social, political, and economic costs. The TRL fishery is integral to Islanders’ aspiration of self-determination and economic autonomy. A more holistic vision inclusive of Islander perspectives is necessary if management of the TRL fishery is to be truly socially and culturally appropriate.     

Seasonal changes in phytoplankton densities in four North Island lakes, 1973–74

In a 1973–74 survey of preserved phytoplankton from Lakes Rotoiti, Rotoehu, Rotoma and Waikaremoana, 205 algal taxa (including 111 Chlorophyta, 56 Chrysophyta, 17 Cyanophyta, 16 Pyrrhophyta, and 5 Euglenophyta) were found. The greatest number of species was found in Lake Rotoehu, but monthly maxima based on cell counts were usually greater in Lake Rotoiti. A summer bloom of the toxic blue‐green alga Aphanizomenon flos‐aquae occurred in Lake Rotoehu. Each lake had its own pattern of dominance. Surface and subsurface samples showed marked differences in species composition and abundance. Diatoms were important winter and spring components, with desmids forming conspicuous subordinates. Cemtium hirundinella was prominent in subsurface layers of Lakes Rotoma and Waikaremoana.

Compound indices (ratios of number of species of most other algae to that of desmids) point to Lake Rotoehu as extremely eutrophic, to Lake Rotoma as moderately eutrophic, and to Lakes Rotoiti and Waikaremoana as oligotrophic rather than meso‐ or eutrophic.     

Study on ecology of foulers on buoys in Dianbai, Guangdong, China

From May to July, 1985, foulers on eleven navigation buoys have been surveyed in Shuidongand Bohe Harbours of Dianbai, Guangdong. Foulers on different parts of buoys (side, bottom and in-side tail tube) were sampled. The thickness and cover area of foulers were measured in the field andall the foulers on an area of 30×30 cm~2 were taken back for lab. identification. Thirty-four quatita-tive samples and several qualitative samples have been got and five hundred and twenty-four sampleshave been classified.     

Biomass of meiobenthic in the Bohai Sea, China

IorasMeiOfauna is a vmp imprtant pep in benthic small bo web energetica1ly duo to theirarell aize and high turnovr rates. A nde Of meMauna op be the recireulaton of nutrient8*Marine nemathe mey keep the bacterial chnies on sand grains in active phase Of gorth byfeding on bacteria, thus enhancing the recirculation Of nutrients (McIntyre, l969; Feller andWrmick, l988; MOntagna et al., l995). But energetics studie8, no matter tfor conductedon the energybudgt level for individua sPeCies or a…     

Dynamic Meteorology Research in Russia, 2015–2018

Izvestiya, Atmospheric and Oceanic Physics - This review outlines the most important results of research in dynamic meteorology performed by Russian scientists in 2015–2018. It is part of the...     

Regionally coherent trends in colonies of African penguins Spheniscus demersus in the Western Cape,South Africa, 1987–2005

From 1987 to 2005, numbers of African penguins Spheniscus demersus breeding in South Africa's Western Cape Province increased by about 50%. Numbers decreased at the four northernmost colonies in the region: Lambert's Bay and the three colonies in Saldanha Bay, although at Jutten Island the decrease is inferred from an estimate for 1987, derived from interpolation. Numbers also decreased at Geyser Rock and Dyer Island on the South Coast. At five colonies between Saldanha Bay and Dyer Island there were large increases. At a sixth colony in that region, Seal Island, where Cape fur seals Arctocephalus pusillus pusillus limit breeding space, numbers remained stable. At two colonies that were initiated in the early 1980s, Robben Island and Boulders, increases were initially rapid (>20% per annum) and matched growth of the South African stock of sardine Sardinops sagax. Strong growth at Dassen and Vondeling islands, between Robben Island and Saldanha Bay, was observed from about 1996–2002, when there was a large increase in the biomass of pelagic fish off South Africa. Increases at colonies between Saldanha Bay and Boulders slowed after 2002, whereas the colony at Dyer Island stabilised at that time. In 2003, a new colony was initiated east of Dyer Island at De Hoop Nature Reserve. These latter trends followed an eastward shift in the distribution of sardine. Small penguin colonies may act as foci for growth in a period when the distribution of prey is changing. Hence, it is important that they be maintained, especially those that, if lost, would increase the isolation of regional populations. Some of the small colonies are less susceptible to oil spills than colonies in the proximity of harbours, and for that reason also are important.     

Assemblage structure,spatial patterns,recruitment, and post‐settlement mortality of subtidal bivalve molluscs in a large harbour in north‐eastern New Zealand

Infaunal bivalve molluscs on the flood tidal delta of Tauranga Harbour, north‐eastern New Zealand, were surveyed twice over a 6‐month period, with the aim of assessing shellfish resources, assessing the magnitudes of temporal and spatial variability in abundances, and identifying potentially important processes. The surveys identified a total of 31 bivalve taxa from 27 sites. Species richness per site ranged between 0 and 9, and varied greatly in space and time, as did two other measures of diversity. Extremely high densities of bivalves (>20 000 m^‐2) were encountered at several sites. Densities of several abundant species varied greatly in time, as a result of recruitment pulses. The abundances of the three species that dominated the fauna (Paphies australis, Tawera spissa, and Ruditapes largillierti) had characteristic spatial scales on the order of 200 m. Comparisons of size frequency distributions for individual sites suggested that mortality or emigration in the first year of benthic life was high. Substantial populations of bivalves occur on Centre Bank, and the most abundant of these are greatly influenced by events early in their lives.     

Water quality and phytoplankton communities in Lake Pontchartrain during and after the Bonnet Carré Spillway opening,April to October 2008, in Louisiana,USA

The Bonnet Carré Spillway, located 28 miles northwest of New Orleans, was constructed in the early 1930s as part of an integrated flood-control system for the lower Mississippi River system. From 11 April to 8 May 2008, Mississippi River water was diverted through the spillway into the 629-square-mile Lake Pontchartrain, which is hydraulically connected to the Gulf of Mexico. On 8 April, prior to the opening of the spillway, water-quality instruments were deployed and recorded hourly measurements of water temperature, dissolved oxygen, specific conductance, pH, and nitrate. Discrete water-quality and phytoplankton (algae) samples were collected in Lake Pontchartrain from 8 April to 3 October 2008 to assess the water-quality nutrient enrichment effects of the diversion on the lake. The maximum influence of river water in the southern portion of the lake was captured with continuous (hourly) monitoring of nitrate concentrations, and field measurements such as of specific conductance during the critical period in late April to early May. By late May, the deployed instruments had recorded the arrival, peak, and decline of selected constituents associated with the freshwater influx from the Mississippi River/Bonnet Carré Spillway diversion. The continuous monitoring data showed the short-term interactions of high-nitrate, low-specific conductance river water and low-nitrate, high-specific conductance lake water. The phytoplankton community composition, as an indicator of water quality, illustrated an extended response from the river water evident even after the continuous and discrete samples indicated that the lake had returned to pre-diversion conditions. The initial phytoplankton community response to nutrient increases was related to accumulations of diatoms. During periods of low nutrient concentrations, accumulations of blue-greens occurred by July and August. As blue-green algae cell densities and biovolumes increased in the summer, so did the species richness of blue-green algae, particularly the harmful algae bloom taxa. Cell densities and biovolume of the phytoplankton lake indicator taxa Skeletonema costatum, Anabaena sp., and Cylindrospermopsis raciborskii were highest and dominated the diatom and blue-green algae communities during the period of most river water influence on the lake and immediately following the freshwater inflows. The dominance and recession of these indictor taxa reflect the dramatic changes that occurred in the phytoplankton community in response to an increase in nutrient-rich freshwater from the diversion into the lake, and not normal seasonal phytoplankton compositional differences. Water-quality data indicated a gradual reversion to pre-diversion lake conditions by June to July, but shifts in the phytoplankton composition were still evident through August 2008. Observations from this study were similar to results from previous studies of Mississippi River/Bonnet Carré Spillway diversion opening in 1997.     

Land use effects on habitat,water quality,periphyton, and benthic invertebrates in Waikato,New Zealand,hill‐country streams

Water quality, habitat, and biota were compared during spring amongst c. 100 m reaches on 11 streams draining pasture, native (podocarp‐broadleaf) forest, and exotic pine forest established on pasture 15 years previously. Differences were greatest between the pasture and native forest streams. Only 1–3% of incident light reached native and pine forest streams whereas 30% reached pasture streams. Pasture streams had 2.2°C higher mean temperature than the native streams, and 5‐fold higher nitrate, 30‐fold higher algal biomass, and 11‐fold higher gross photosynthesis. Native streams were 60% wider than pasture, with pine streams intermediate. Pine and pasture streams had 3‐fold higher suspended solids and fine sediment stored in the streambed than native streams. Woody debris volume was 17‐fold greater in pine than pasture streams, with native streams intermediate. Invertebrate taxa richness did not differ between land uses. Community composition differed most between pasture and native forest, with pine forest streams intermediate. Invertebrate densities were 3‐fold higher in pasture than native streams, mainly because of more chironomids and snails, but mayflies, stoneflies, and caddisflies densities were 2–3‐fold higher in forest streams than pasture.     

Vertical Variability of Primary Production and Features of the Subsurface Chlorophyll Maximum in the Laptev Sea in August–September, 2015, 2017, and 2018

Oceanology - The vertical distribution of phytoplankton primary production (PP) and chlorophyll a (Chl) was studied based on the data carried out in August–September 2015, 2017, and 2018. The...     

Some observations on phytoplankton species composition,biomass, and productivity in Kenepuru Sound,New Zealand, 1982–83

Phytoplankton species composition, biomass, and rates of primary production were determined at two sites within Kenepuru Sound, New Zealand, in spring, summer, and autumn of 1982–83. Microflagellates and ultraplankton (< 5–10 μm) were numerically very abundant on each occasion and small gymnodinoid nanno‐planktonic (< 10–15 μm) dinoflagellates were likewise always a common component of the populations. The dinoflagellate, Prorocentrum gracile, made a substantial contribution to the total biomass in summer. The diatom community changed from mainly small chain forming species (Chaetoceros spp., Leptocylindricus spp.) in spring to small solitary centric and pennate forms (Nitzchia longissima, Coscinodiscus spp.) in summer, to a diversity of larger taxa (Coscinodiscus concinnus, Eucampia zoodiacus) in autumn. The autotrophic ciliate Mesodinium rubrum was a particularly important member of the autumn photo‐autotrophic assemblage. Both phytoplankton biomass and productivity increased from spring to autumn. In situ rates of primary production ranged from 15 to 1420 mgC m^‐2h^‐1 and chlorophyll a concentrations ranged from 6.9 to 258.5 mgChl a m^‐2. A gross primary production rate, in summer, was estimated at 0.57 gC m^‐2 d^‐1. Phytoplankton production and biomass appeared to be related to dissolved inorganic nutrient concentrations as a result of variations in the freshwater inflow. A tentative comparison between the rates of phytoplankton and cultivated mussel production is made.     

Petrology, Geochemistry and Nd-Sr-Pb Isotopic Properties of Volcanic Rocks in Daheishan Island, Penglai, Shandong Province

The major elements, trace elements, K-Ar age and Sr-Nd-Pb isotopic systems of the Cenozoic volcanic rocks in Daheishan Island and Cishan, Penglai, Shandong Province are measured. The volcanic rocks ( olivine-nephelinite and nepheline-basanite ) in DaheishanIsland erupted periodically in an interval of 0.32 Ma, from 8.72 Mm 8.39 Ma, 8.08 Ma to 7.73Ma. The volcanic rocks are all rich in light REEs. They are similar to the OIB-type alkali basalt in the trace elements normalized model by primordial mantle: rich in high field elements such as Nb and Ta, and imcompatible elements such as Cs, Rb, Ba, Th, U. The volcanic rocks show a depletion of K and Rb elements. It is suggested by the trace elements that the olivine-nephelinite in Daheishan Island is originated fi‘om deep resources under the continental mantle, ε Nd (0) values of the volcanic rocks in Daheishan Island and Cishan are 5.31 - 8.51 and 7.33 respectively, suggesting that the volcanic rocks are from the depleted mantle resources, which have higher Sm/Nd ratios than the CHUR. ^143Nd /^144Nd ratios of Daheishan Island olivine-nephelinite and Cishan alkali basalts are 0.512 910 - 0.513 074 and 0.513 014 resoeetivelv. The ^87Sr /^86Sr of Daheishan lsland volcanic rocks are lower than that of Cishan, 0.703 427 - 0.703 482 and 0.703 895 respectively. The Daheishan Island olivinenephelinite has the Pb isotopic values as follows: ^206Pb /^204pb= 18.028 9 ～17.972 8,^207Pb /^204Pb= 15,435 8 - 15.402 2 and ^208Pb /^204Pb=38.087 6 - 37.997 5, lower than those of Cishan basanite. The Cishan basanite has ^206Pb / ^204Pb = 18.240 1, ^208Pb /^204Pb = 15.564 5 and ^208Pb /^204Pb=38.535. The authors suggest that the olivine-nephelinite in Daheishan Island is similar to the E-type MORB or Hawaii OIB, and the alkali basalts in Cishan similar to the Kerguelen OIB. The dominant mantle components of DM PREMA and perhaps DM( Dupal type ) are the dominant mantle components for volcanic rocks in Daheishan Island and Cishan. The PREMA component plays an important role.     

Species Diversity and Abundance Distribution of Pelagic Siphonophores in Nan Wan Bay of Taiwan, China, in Late Autumn and Early Winter

Zooplankton surveys were carried out on November 2-3 and December 8-10, 2001 at 12 stations in the Nan Wan Bay of Taiwan, China. Altogether 92 quantitative zooplankton samples were collected from subsurface water and bottom water layers with two conical plankton nets （180 cm in length, 45 cm in opening diameter, 333μm and 200 larn in mesh size）. A total of 31 species of Siphonophores were identified, among them 7 species are new records in the waters around Taiwan Island, of which Rocacea cymbiformis is a new record in China. Dominated by Chelophyes appendiculata, Bassia bassensis, Diphyes bojani, Diphyes dispar, Abylopsis eschscholtzi and Chelophyes contorta, these species accounted for over 76 % and 63 % of the total abundance in November and December. The species number and Siphonophores abundance in December （25 species, 1.99 inds/m3） were more than those in November （19 species, 0.438 inds/m3）, and they were more in the surface water layer than in the bottom layer at most sampling stations. In early winter, the offshore high salinity water mass was a main factor influencing the distribution. The sampling efficiency for two plankton nets is discussed and the seasonal variation of species number and abundance in the Nan Wan Bay is compared with that in the neighboring waters.     

Pilchard distribution in South African waters, 1983–1985

Seasonal movements of South African pilchard Sardinops ocellatus in the relatively abundant 1982/83 year-class are inferred by means of length frequency information from predator diet analyses and from commercial and research catches in various localities. Pilchard of approximately one year of age were most abundant in the vicinity of Algoa Bay on the south-eastern Cape coast in the summer of 1983/84. The pilchard length frequency distribution in gannet diet and research midwater trawl samples in this area provided a clear linkage, through the known juvenile growth rate, with fish of an average 6 months of age, which were abundant off the West Coast during May 1983. Pilchard in this year-class were subsequently found to be widely distributed over the Agulhas Bank, with a tendency for them to inhabit deeper water towards the shelf edge as they reached the age of first spawning (about 18 months). During 1985, a noticeable increase in the abundance of large, two-year-old and older pilchard in the diet of West Coast gannets and in West Coast commercial catches indicated a movement of 1982/83 year-class fish into that area. The changes in distribution of pilchard in this year-class are discussed in relation to seasonal differences in the marine environment off South Africa.