Seasonal variations of phytoplankton diversity in the Coleroon coastal waters, southeast coast of India

The results of an investigation carried out during June 2005 to May 2007 on physico-chemical parameters,species composition and community structure of phytoplankton including Chlorophyll a(Chl-a) at the Coleroon coastal waters(Southeast coast of India) are reported.Air and surface water temperatures(°C) varied from 25.1 to 30.1 and from 24.5 to 28.5 respectively.Salinity values varied from 6 to 28.5 and the pH ranged between 7.0 and 8.3.Variation in dissolved oxygen content was from 3.1 to 7.5 mg/dm-3 while the light extinction coefficient values(LEC) ranged between 3.1 and 10.1 cm.The ranges of inorganic nutrients(μmol/dm-3) viz.,nitrate,nitrite,phosphate and silicate were 10.1-23.4,1.2-8.9,0.2-3.1 and 55-125,respectively.The ranges of Chlorophyll a(μg/dm-3) values was 2.0-7.5.Presently,124 phytoplankton species representing different classes viz:Bacillariophyceae(77),Dinophyceae(19),Cyanophyceae(15),Chlorophyceae(10) and Chrysophyceae(3) were recorded.The phytoplankton cell abundance varied from 0.290 to 111.662 cells/cm-3,with peak diversity(3.38 bits/ind.) during summer season.The maximum abundance was found during summer season coinciding with the stable hydrographical conditions.The seasonal distribution and abundance of phytoplankton are discussed in relation to hydrographical parameters.Canonical Correspondence Analysis(CCA) was applied in this paper for discriminating environmental factors having effect on phytoplankton community at species level.Coleroon coastal water is subjected to long term fluctuations in physico-chemical parameters depending upon the seasonal tidal amplitude and freshwater influx resulting in a continuous exchange of organic,inorganic,plant and animal matters.     

A Note on Tsunami Bore Front

A note is presented on tsunami bore front. This tsunami bore front is an old dynamical problem but also a new problem to be understood. The tsunami event on 2004 December 26 has raised this is an urgent problem. The author introduces here a model in order to see a hydrodynamical specific property of the tsunami bore front. This modeling gives us a new understanding about what mechanics is for the interested tsunami bore front, especially, around a coastal zone. This work adds a new understanding about mechanics of water motions as the tsunamis generated by the earthquake undersea at a distant area from the coast. The model in this work points out a specific transitional pattern as a function of time and space of tsunami bore front. This modeling gives what is essential at considering tsunami bore front.     

Three sipunculan species (two new) from New Zealand

Two new species of Sipuncula arc described from New Zealand; Phascolion temporariae from, the empty tubes of the polychaete Temporaria inexpectata (Mestayeri), and Phascolion tortum from the shells of four species of molluscs. Specimens of Golfingia improvisa (Theel) are also reported from the empty frustules of the foraminiferan Ammodiscoides mestayeri (Cushman) and the sandy tubes of the foraminifera Rhizammina sp. All the species were dredged at depths of 370–660 m from Taiaroa and Papanui Canyons, off the Otago Peninsula, New Zealand. The body cavity of several specimens of G. improvisa contained the larval stage of a nematode.     

Northern Adriatic phytoplankton response to short Po River discharge pulses during summer stratified conditions

A 275‐km‐long transversel Northern Adriatic profile from the mouth of the Po River (Italian Adriatic coast) to the Kvarner region (Croatian coastal island area) was investigated in three successive case studies in August 2008, 2009 and 2010. The short Po River pulses in August result in the surface advection of riverine water, nutrients and phytoplankton from the western to the eastern side of the Adriatic. This surface spreading exhibits inter‐annual variability depending on the riverine discharge in the preceding period. The Po River discharge pulse in August 2010 in particular resulted in an extraordinary tongue‐like advection of riverine water, nutrients, and phytoplankton towards the Eastern Adriatic coast. The phenomenon was detected using both satellite imagery and classical oceanographic measurements. In the advective water, toxic dinoflagellates were most abundant in August 2010, when the influence of the Po was greatest.     

Food and energy in the diet of brown and rainbow trout from Lake Benmore,New Zealand

The diet of brown trout (Salmo trutta) and rainbow trout (S. gairdnerii) was studied in specimens from Lake Benmore, a deep, oligo‐trophic lake in South Island, New Zealand. Between November and July, both species fed mainly on small molluscs (Potamopyrgus antipodarum, Physa sp., and Gyraulus corinna) gleaned from the littoral weed beds. Energy values for the three species of mollusc were determined: P. antipodarum, 6000 J g^‐1; G. corinna, 5500 J g^‐1; Physa sp., 9800 J g^‐1. Potamopyrgus antipodarum yielded little energy to the fish, unless its shell broke during passage through the gut. Physa sp. was the most profitable mollusc, irrespective of shell breakage and Potamopyrgus antipodanim the least profitable. The mean energy value per snail for G. corinna and Physa sp. eaten by rainbow trout was 25–30% less than for snails eaten by brown trout, possibly because rainbow trout ingested empty shells from the sediment surface. Rainbow trout extracted about 20% more energy than brown trout from unbroken shells. In July, 84% of the brown trout switched to predation of common bullies, Gobio‐morphus cotidianus, probably as a result of bully reproductive behaviour. Rainbow trout did not show the same change, apparently because they were feeding in deeper water where few bullies were available. The low‐energy diet and its possible connection with growth rate are discussed.     

海阳市典型砂质海岸侵蚀机制与防护对策研究

海阳市砂质海岸资源丰富,延绵近120 km,尤以万米沙滩浴场著称,但近年岸滩侵蚀严重影响其社会经济发展.本研究基于海阳市羊角畔两侧长约20 km典型砂质海岸连续3 a的海岸线蚀和典型剖面蚀淤调查,定量化研究海滩侵蚀及其变化,辅以一维数值模型,研究人类活动影响下的泥沙运动特征和海滩侵蚀机制.研究结果表明,调查区42.5％...     

Trophic interactions of the pelagic ciliate Stentor spp. in North Patagonian lakes

The zooplankton of oligotrophic lakes in North Patagonia is often dominated by mixotrophic ciliates, particularly Stentor amethystinus and Stentor araucanus. Therefore, we tested whether Stentor spp. (i) is an important food for juvenile endemic (Cheirodon australe, Galaxias maculatus, Odontesthes mauleanum, Percichthys trucha) and introduced (Oncorhynchus mykiss) fish species, and (ii) represents a remarkable grazer of bacteria. Ingestion rates of fish estimated by disappearance of Stentor in feeding experiments ranged between 8 (G. maculatus) and 53 (C. australe) ciliates per fish and day, and assimilation rates measured by using radioactively labelled Stentor ranged between 3 (P. trucha) and 52 (C. australe) ciliates per fish and day. However, although we detected the consumption of Stentor by fish, the daily consumption amounted to at most 0.2% of the fish biomass which can not cover the energy requirement of the fish. Furthermore, the daily consumption was equivalent to a maximum of 1.6% of the Stentor standing stock so that fish predation does not seem to be an important mortality factor for the ciliates. The clearance rate of Stentor sp. on natural bacteria was on average 3.8 μl cil⁻¹ h⁻¹. The daily ingestion (mean 3.9 ng C cil⁻¹ d⁻¹) was about 3.5% of the individual biomass of Stentor sp. Therefore, bacteria ingestion might explain a ciliate growth rate of appr. 1% d⁻¹, which was about 17% of the photosynthesis of endosymbiotic algae. The maximum density of Stentor sp. in the lake could ingest about 1 μg C L⁻¹ d⁻¹ bacteria which is only 3% of average bacterial production. Thus, grazing by Stentor sp. does not seem to be a main loss factor for the bacteria.     

闽东南沿海老红砂沉积地层与形成时代

采用岩石地层学、磁性地层学和地球化学等方法,结合TL、ESR和¹⁴C等测年,对广泛分布于闽东南沿海的老红砂沉积地层及其形成时代进行了划分。结果表明,该区老红砂沉积地层可综合划分为5个地层段,其中老红砂层可分出3个地层段,分属60~40 ka B.P.、30~25 ka B.P.和20~10 ka B.P.所形成;两个古土层,反映大约在40~30 ka B.P.和25~20 ka B.P.老红砂的发育有过两次较长时间的沉积间断或减弱。     

The Effect of Tsunami in 2004 on Mangrove Forests,Nias Island,Indonesia

The earthquake and tsunami that devastated coastal area in Nanggroe Aceh Darussalam Province and North Sumatra Province,especially Nias Island on December 26,2004,caused damage to most mangrove and coastal forests in the areas.Before the 2004 tsunami,there is no report or publication about mangrove and coastal vegetation in Nias Island.The aims of this research were to describe the mangrove forests and coastal vegetation after tsunami disaster and to learn the ecological functions of mangrove forests and co...     

'There is a tide': An examination of the evolution of New Zealand Coastal Policy Statements

Abstract:   In this paper the proposed New Zealand Coastal Policy Statement is set within the context of its Resource Management Act legislative framework and in terms of the evolution of the fundamental influence of policy statements on coastal management in New Zealand. This discussion is coupled with an examination of the development of strong policy directions in the proposed statement and the potential impact of giving effect to these policies on the regional and unitary authorities tasked with this responsibility.