Spawning periodicity and habitat of the palolo worm Eunice viridis (Polychaeta: Eunicidae) in the Samoan Islands

The relationship between the phase of the moon and the emergence of the epitokous segments of the palolo worm Eunice viridis Gray has been known to the natives of the Samoan Islands for centuries. They predict the date and time of day when the emergence occurs so that they can be ready to catch the worms. This phenomenon is one of the best known examples of lunar periodicity. It was first described scientifically at the end of the last century. My own investigations concern the occurrence of the worms in the reef, in which they gnaw long tunnels through the massive blocks of coral limestone at levels characterized by the occurrence of symbiotic algae. Apparently the algae are the main sources of nutrition for the worms. The casting off of the epitokous segments occurs at the third quarter of the moon in October or November. An analysis of known dates on which the swarms of worms have appeared permitted a precise method of prediction to be formulated. The causality of this periodicity is discussed.     

Studies on enzymes associated with calcification of the cuticle of the hermit crab Clibanarius olivaceous

In the anomuran Clibanarius olivaceous Henderson, the cuticle of the cephalic and thoracic regions is calcified, while that of the abdominal region is uncalcified. Histochemical observations have been made on the possible enzymes involved in the process of calcification of cuticle. The calcified regions show the presence of enzymes such as phosphorylase, alkaline phosphatase and carbonic anhydrase. The possible role of phosphorylase in calcification may be production of phosphoric esters, which form the required substrate for alkaline phosphatase. The latter appear to be associated with the production of phosphate ions from phosphoric esters. The carbonic anhydrase may be associated with the production of carbonate ions. The suggestion that these enzymes are involved in the process of calcification is further supported by experimental evidence of inhibition of the action of enzymes by enzyme inhibitors. The inhibition of enzymes leads to reduction in the amount of calcium added to the cuticle.This paper formed part of a thesis approved for the award of Ph. D. degree of the University of Madras.     

Effects of simulated deposition of dredged material on structure of nematode assemblages – the role of contamination

 Certain criteria must be satisfied before a licence for the deposition of dredged material at sea in UK waters is issued. These relate to the chemical quality of the material, the quantity to be disposed of, its nature and origin, and its predicted impacts at the disposal site. Although chemical analyses of dredgings provide an indication of the relative degrees of contamination, they do not provide a measure of any resultant biological effects. A laboratory experiment was therefore designed to investigate the effects of the degree of contamination and the role of burial associated with the deposition of dredged material on the meiofauna. Estuarine nematode assemblages were exposed to the simulated deposition of uncontaminated, oxic intertidal mud and anoxic sediments from the Mersey and the Tees estuaries, both of which were contaminated with heavy metals. The sediments, which differed little in terms of grain size, were deposited in two different frequencies. Nematodes showed a clear species-specific response to the experimental treatments, depending on the frequency of deposition and the chemical quality of the deposited material (e.g. metal and oxygen concentrations). The response of nematode assemblages was mainly determined by the deposition frequency rather than the type of sediment or the degree of contamination. The deposition of sediment in one large dose at the beginning of the experiment caused more severe changes in assemblage structure than the same quantity deposited in several smaller doses. Although lower than in uncontaminated mud, relatively high migration and survival rates in the contaminated high-frequency treatments were observed. This may have been due to reduced bioavailability of metals and the tolerance of estuarine nematodes to both metal contamination and the deposition of small sediment volumes at regular intervals. The observed trends demonstrate the potential of small-scale laboratory experiments for testing the quality of contaminated dredged material at the licensing stage, i.e. prior to the issue of a disposal licence. Received: 11 February 2000 / Accepted: 26 June 2000     

Sensitivity analysis of a theoretical energy balance model for water temperatures is small streams

Relative sensitivities were computed to determine the importance of the variables to the system. Sensitivity functions were used to predict the nature of the relationships between water temperature and the variables. Unlike earlier studies, this treats a stream subject to intense solar heating. The consequently elevated water temperatures, cause heat loss components to be significant. Evaporation and conduction are the most important. The analysis indicates that the wind spped, the thermal properties of the streambed, the season, its depth, and the amount of shading are the most important variables. The initial water temperature and the ambient water vapor pressure are less important. The air temperature, the albedo of the streambed, and the annual mean air temperature are of little importance. Neither the amount of turbulence in turbulently flowing water, nor the latitude of the stream has an effect. The model allows the trends of the system to be predicted on the basis of easily measurable variables. Hence, the difficulty of measuring the energy balance components may be avoided.     

安徽沿江地区4种蛇的染色体组型、C带和Ag-NORs研究

本文报道游蛇亚科４种蛇的核型、Ｃ带和ＡｇＮＯＲｓ,结果：黄链蛇２ｎ＝４６．虎斑游蛇２ｎ＝４０,第４号染色体（Ｎｏ．４）有随体．鸟梢蛇和紫灰锦蛇２ｎ＝３６,鸟梢蛇的Ｎｏ．５短臂近着丝粒区有一次缢痕．虎斑游蛇Ｎｏ．５为性染色体,其余３种的性染色体为Ｎｏ．４．这４种蛇均为ＡＦ＝５０;Ｃ带型的种属性特征明显,其中紫灰锦蛇的端粒型Ｃ带特别发育,其余三种以着丝粒Ｃ带较发达．黄链蛇、虎斑游蛇和紫灰锦蛇的Ｗ染色体Ｃ带正染呈现整条异染色质化;银染结果４种蛇均只显示一对ＮＯＲｓ,但其分布不同,其中虎斑游蛇ＮＯＲｓ呈异态现象．文章讨论了核型的演化和次缢痕、ＮＯＲｓ及Ｃ带的关系     

The possible causes of diel vertical migrations of planktonic animals

Experimental measurements of the sinking velocity of anaesthetized planktonic animals carried out in the first half of this century prove that the downward migration of planktonic populations may be entirely attributed to passive sinking. This conclusion, along with data from voluminous literature devoted to circadian rhythms, supports the supposition that diel vertical migration is the result of an innate alternation of phases of high and low activity. During the phase of low locomotory activity, a passive sinking of an organism of negative buoyancy takes place; during the phase of high activity, the same organism actively climbs to the surface using the well-known mechanisms of space orientation. This hypothesis offers an explanation both of the usual course of diel migration and various deviations from this course, some of which are mentioned here. If the above considerations are correct, and if we admit that one of the trends of the evolution of pelagic organisms is directed towards the reduction of energy expenditure for the maintenance of the body in a suspended state, i.e. towards neutral buoyancy, the conclusion may be drawn that diel vertical migrations are not the result of adaptation to the planktonic mode of life.     

Analysis by slow-motion picture photography and scanning electron microscopy of radular function in Urosalpinx cinerea follyensis (Muricidae,Gastropoda) during shell penetration

Radular function in the muricid gastropod Urosalpinx cinerea follyensis Baker during shell penetration was examined with slow-motion picture photography and scanning electron microscopy. Particular attention was paid to possible injury of buccal structures by radular cusps. The presence of a flexible cuticulated buccal armature, and delicate synchronization of movements of odontophoral cartilages, subradular membrane, teeth, and buccal mass, explain the absence of shredding of live buccal tissues. Some light abrasion was evident, but generally only in the cuticulated gully of the subodontophoral shield, on the rim of the jaw, and on the anterior edge of the esophageal valve. Rasping at the surface of incomplete bore-holes is done by major cusps of rachidian teeth over the bending plane. Marginal teeth lie on the slopes of the odontophore, generally remain depressed below the level of rachidian teeth, and thus scrape the shell only lightly, if at all. The sharp posteriorly recurved shape of central and lateral rachidian cusps enhances their scooping effectiveness. These teeth produce smooth, conspicuous traces in the soft shell of Mya arenaria and shallow traces in the harder shell of Mytilus edulis Linné. The impact of individual cusp strikes was not evident in traces. With wear, rachidian cusps become increasingly blunted, a reflection of their ploughing action over chemically weakened shell, and are eventually sanded flat. Marginal teeth wear primarily at their ends, the tips becoming truncated as they pass lightly over the shell surface. The advancing edge of the odontophore during rasping strokes, plotted on the image from motion pictures moves slowly at first, then more rapidly in the middle of the stroke, and slows again at the end. Duration of strokes ranged from 0.45 to 0.75 sec. Duration of rasping cycles varied from 1.3 to 2.0 sec. The number of transverse rows of teeth passing over the bending plane during the rasping stroke varied from 14 to 32, and the average time for the passage of one transverse row over the bending plane ranged from 20 to 48 msec. The number of transverse rows of teeth remaining exposed beneath the odontophore below the bending plane at the end of the rasping stroke, and between the bending plane and the anterior end of the sulcus in the radular diverticulum, was approximately 10.     

节约型社会提出的现实背景、理论前提及其法律内涵

通过对节约型社会提出的现实背景的阐述,认为节约型社会的理论前提和基础有生态政治理论、环境资源承载能力理论、资源生态经济理论、资源生态化和环境资源化理论等。并对节约型社会的目标、节约型社会的理念、基本原则等进行了探讨。最后在以上分析的基础上对节约型社会的法律内涵进行界定。认为节约型社会在第一层面的涵义是以供定需的发展战略和资源禀赋导向型的发展规划;第二层面的内涵是资源生态承载能力范围内的经济发展道路选择;第三层面的内涵是对自然资源进入社会经济生产的全过程进行规划和调控。     

Notes on the benthic bionomy of the N-NE Brazilian shelf

This paper deals with the bionomy of the sea bottoms of the N-NE Brazilian continental shelf, between Cape Orange and the State of Sergipe, south of São. Francisco River. It is based on data collected by the Instituto Oceanográfico, Recife, Brazil, during several surveys conducted in that area. Special emphasis is placed on the characteristics of the bottom, chiefly surveyed by means of dredging, as well as on the biological populations living on the different substrata. The sector of Recife, investigated in more detail, provides a general scheme of population delimitation. The study is applicable to the rest of the N-NE Brazilian region. The great extent of the mud or muddy sand bottoms gives the Amazonian coasts a very typical aspect. The rest of the area is remarkable for the predominance of calcareous algae of the Melobesiae group. Some biogeographical considerations are presented regarding the northern and southern limits of the NE Brazilian region. Finally, it is attempted to define the bionomical significance of the bottoms studied, comparing them with similar and better knwon biotopes from the Mediterranean Sea and SW Indian Ocean.Based on recent data collected by the Instituto Oceanográfico, Recife, Brazil.     

The formation of protective dune ridge along the Southeast Baltic Sea coast: historical and social aspects

This paper is based on literature-based studies, as well as material collected by the author over more than 30 years on the shores of the Southeast Baltic Sea. In order to protect roads running along the shoreline from East Prussia to Königsberg, local shore reinforcement works commenced in the fifteenth century, although some individual attempts had been made before. In 1684, M. Ch. Hartknoch theoretically substantiated the necessity for, and methods of, shore reinforcement. The state of the shores deteriorated considerably during the Seven Years War (1756–1763), when woodlands growing along the shores were completely destroyed; hence, nearly 100 km length of the coast of the Kur?i? Nerija (Curonian) sand spit was left without any vegetation. Aeolian sand buried as many as fourteen settlements. This situation forced the authorities to organise maintenance of the coast and the dunes at the governmental level, and to start the formation of an uninterrupted dune ridge. The second half of the nineteenth century and the first half of the twentieth century are notable for the extensive construction of new ports. Along the shores running from the Sambian Peninsula to the Gulf of Riga, eight port engineering structures had been constructed with the intervals of approximately 26 km between the ports of Klaip?da and Liepaja, and every 13 km between Palanga and Pape. Shore management measures were being implemented simultaneously, thus ensuring the functioning of the above-mentioned coastal protection structures and the reduction of impacts upon the shores. In the second half of the twentieth century, ports were dredged and developed significantly. Their entrance channels reduced the long-shore sediment transport. Moreover, total sand reserves in the shore zone also diminished. The processes of erosion of the beaches and the dune ridge made it necessary to actively reinforce the shore. A number of countries passed legal acts governing the protection and use of the shore zone. At the turn of the twenty-first century, the incompatibility of such priorities in human activities as sea transport and recreation with nature protection has become evident. The conflict of interests in the Kur?i? Nerija National Park, the port of Klaip?da, and the resort of Palanga serve as good examples of such incompatibility. The conclusion that can be drawn that in twenty-first century is that the priorities in general coastal management should be as follows: harmonisation of interests among the states and individual fields of activities, as well as measures aimed at neutralisation of negative natural trends (higher frequency of storms, global rise of water level, etc.). The protective beach dune ridge will further play the role of efficient means for reducing shore erosion.     

天南星（Arisaema erubescens Schott）对钉螺（Oncomlania hupensis）的毒杀作用

近年来,血吸虫病在我国又有回升的势头,采用植物灭螺进而消灭血吸虫病是控制血吸虫病蔓延的有效方法.实验研究了一种新型灭螺植物——天南星(ArisaemaerubescertsSchott)的灭螺效果和机理.采用天南星植物水浸液用于灭螺(Oncomlaniahupensis)实验,并检测天南星处理后钉螺肝脏生理生化指标的变化.结果显示,天南星全株均具有较强的灭螺效果,其中块茎灭螺效果最好:0.1%块茎水浸液处理3天后钉螺死亡率达88.4%,5天后达100%;天南星不同部位的灭螺效果为:块茎>叶>茎.天南星块茎水浸液处理钉螺后,随处理浓度的增加和处理时间的延长,钉螺肝脏丙二醛(MDA)含量显著升高,而过氧化物酶(POD)和超氧化物歧化酶(SOD)活性显著降低.天南星水浸液可引起钉螺肝细胞的过氧化损伤,导致其抗氧化能力下降,从而降低了其代谢和解毒功能.研究结果表明,天南星是一种具有良好灭螺效果的植物,可成为构建植物群落生态工程灭螺林新的物种资源.     

Public expenditure and the environmental management of Brazilian municipalities: a panel data model

Environmental expenditure can be classified as an indicator to measure the efforts of public agents with the environment. Cities and countries seek to understand the determinants of environmental spending over time. This research aims to analyze the variables that influence the environmental spending of Brazilian municipalities between the years 2012 and 2016. Thus, this research helps fill the gap on lack of longitudinal research that involves local contexts in relation to public municipal expenditures on the environment. The research method consists of the panel data model. Data were collected on the environmental expenditures of the municipalities and other variables of 4269 Brazilian municipalities, the collection generated 21,329 observations. The results showed that the municipalities of the state of Amapá had better relative expenditure averages, it was also observed that the municipalities in the Northeast region show the worst results. The municipality of Itamaracá, located in the state of Pernambuco, presented the best percentage of the country, 9.47% of the environmental expenditure in relation to total expenditure. Regarding the results of panel data, the variables revenue, population, density, GDP, and HDI presented significance in all models; the models estimated by fixed effects ensure the consistency of the parameters.     

南通市城镇化过程中水环境调控研究

城镇化是涉及诸多影响因素的复杂动态过程,而水环境又是城镇化进程中最为显著的问题.文章首先介绍了南通市城镇化的发展历程,通过分析城镇化进程中水环境问题,提出了强化水资源保障能力、增强水环境承载能力,提高水灾害防御能力,提升水经济调控能力等有效措施和对策.参13.     

宁波市某人工泻湖浮游生物变化特征及影响因素分析

以宁波市北仑区梅山水道形成的人工泻湖为研究对象,在不同季节进行水质及浮游生物调查,分析其浮游生物时空分布特征与水质的关系。4个采样点共检出浮游植物66种,以硅藻为绝对优势种,检出浮游动物25种,主要为桡足类、少量轮虫及网纹虫;拦坝后水道内浮游生物密度有了数量级增长,各项生物评价指数降低,但各采样点仍处于中污染水平。监测理化参数表明,研究水域在拦坝后盐度下降、悬浮物浓度下降,氮磷含量无明显变化;水域大部分点位处于中度富营养化水平。结合浮游生物分布与理化参数进行分析,发现堤坝合龙后,水道内侧海水淡化、悬浮物含量下降,导致浮游生物密度上升、生物多样性下降、出现淡水优势种群;营养盐含量不是浮游生物生长的限制因子,对浮游生物分布无显著影响。     

Implementation obstacles of the ICZM protocol and mitigation efforts

After the signing of the ICZM Protocol in the Mediterranean (Madrid, 21 January 2008) its implementation became the main focus of interest for the future. Several obstacles on the way to implementation are briefly analysed, starting with the ratification process, the competence for the implementation and the availability of financial resources to put the Protocol requirements in place. A list of mitigation actions is proposed in order to overcome these obstacles. The ways in which the Centre responsible for assisting the countries can implement this legal instrument (i.e. PAP/RAC) is elaborated in the second part of the paper. This includes the preparation of a stocktaking report to allow for defining the starting point for ICZM in the Mediterranean, elaboration of an explanatory guide of the text of the Protocol, as well as guidelines for the definition of a coastal setback. Equally important is awareness-raising and training for the implementation of the Protocol.     

Analysis of Wind-Induced Thermocline Oscillations of Lake Tanganyika

An analysis is presented of the wind-induced thermocline oscillations of Lake Tanganyika, East Africa. The region undergoes a four month dry season and the wet season for the rest of the year. The dry season is characterised by nearly constant high southeasterly winds, while for the rest of the year mild wind blows generally from the northeast. Observations show that the dry season high winds cause tilting of the thermocline, being higher/lower than normal at the southern/northern ends of the lake. The thermocline tries to restabilise itself after the cessation of dry season winds and oscillates for the rest of the year. A non-linear reduced-gravity model is used to study the thermocline oscillations of the lake. The numerical simulations satisfactorily represent the oscillations, their period and amplitude. Different forcing conditions (thermocline depth, wind stress and stability) are used in the model and their effect on the period and amplitude of the oscillations are studied. The amplitude of oscillations ranges from 15 to 45 m, while their period varies from 3 to 4 weeks according to the variation in the model parameters. Wavelet transform is used to study the evolution of periods of oscillations with depth in the time series of observations and along the length of the lake using model simulations. Wavelet spectra presents several dominant modes including the semidiurnal, diurnal, synoptic, intraseasonal variability, besides the modes representing the wind-induced thermocline oscillations.     

污染场地中有机氯农药对土壤原生动物群的影响

有机氯农药污染土壤对生态环境具有潜在的风险。采集某废弃农药厂污染场地的土壤样品,测定了土壤的理化性质,以及典型有机氯农药滴滴涕(DDTs)和六六六(HCHs)的残留浓度,并对土壤中原生动物的组成和数量进行了分析。结果显示,农药厂区域的土壤中原生动物的组成结构为:鞭毛虫和肉足虫为优势类群,纤毛虫为稀有类群。土壤理化性质与原生动物数量的相关性分析表明,总氮含量与鞭毛虫、纤毛虫数量和原生动物总数量呈显著正相关,总磷含量与肉足虫数量呈显著正相关。同时,农药厂区域土壤中的原生动物数量较对照区显著减少,污染场地中长期残留的有机氯农药对原生动物有明显抑制作用。     

Topological structure and interaction strengths in model food webs

We report the results of carrying out a large number of simulations on a coevolutionary model of multispecies communities. A wide range of parameter values were investigated which allowed a rather complete picture of the change in behaviour of the model as these parameters were varied to be built up. Our main interest was in the nature of the community food webs constructed via the simulations. We identify the range of parameter values which give rise to realistic food webs and give arguments which allow some of the structure which is found to be understood in an intuitive way. Since the webs are evolved according to the rules of the model, the strengths of the predator–prey links are not determined a priori, and emerge from the process of constructing the web. We measure the distribution of these link strengths, and find that there are a large number of weak links, in agreement with recent suggestions. We also review some of the data on food webs available in the literature, and make some tentative comparisons with our results. The difficulties of making such comparisons and the possible future developments of the model are also briefly discussed.     

分子生物学方法在微生物多样性及微生物生态研究中的应用

首先介绍了分子生物学技术在微生物多样性及微生物生态研究中应用的理论基础，以及在此基础上引入的分子生物学技术如：PCR、DNA杂交技术在分子层面上来研究微生物遗传多样性，并结合已有工作积累展望了分子微生物生态研究的发展前景．图2参20     

渍水土壤中硒迁移行为的研究

用土柱模拟4种加硒处理的土壤还原淋溶过程，研究了硒在土壤中的迁移和积累。结果表明，未加硒处理（土壤背景硒）的溶液中硒的迁移以有机硒占优势，Se(Ⅵ）及Se（Ⅳ）占的比例很小；土壤富野酸硒由上层向下层迁移。外源蛋白硒的处理的溶液中硒迁移为有机硒，部分外源硒以富里酸硒积累在下层土壤。外源Se(Ⅵ）和Se（Ⅳ）处理的溶液中硒迁移量只占加入量的0．2％和0．4％，硒迁移的主要形态前者为有机硒，后者为Se(Ⅳ）和有机硒；外源Se（Ⅵ）和Se(Ⅳ）的绝大部分以富里酸硒的形态积累于土壤，其积累量Se（Ⅵ）处理高于Se(Ⅳ）处理，上层土壤高于下层土壤。