Diversity and ecology of algae from the Nahal Qishon river,northern Israel

In 59 samples of periphyton and phytoplankton collected in 2002 - 2003 from the Nahal Qishon (Qishon River), northern Israel, we found 178 species from seven divisions of algae and cyanoprocaryotes. Diatoms, clorophytes, and cyanoprocaryotes prevail. Nitzschia and Navicula (Bacillariophyta) are the most abundant. Most of the species are cosmopolitan or widespread, except Lagynion janei (Chrysophyta), which is endemic for the Mediterranean Realm. About 17% of species (26) are new for Israel and five of them represent the first recorded genera: Crinalium endophyticum Crow, Actinocyclus normanii (Gregory) Hustedt, Rhizoclonium hieroglyphicum (Agardh) Kütz (Chlorophyta), Lagynion janei Bourelly, and Stylococcus aureus Chodat. Most of them come from a rare riverine assemblage with red alga Audouinella pygmea, as well as from the estuarine assemblage. Alkaliphiles predominate among the indicators of acidity, with few acidophiles confined to the communities under the impact of industrial wastes. Among the indicators of salinity, most numerous are the oligohalobien-indifferents and species adapted to a moderate salinity level. The relative species richness of ecological groups and the indices of saprobity are correlated with changes in conductivity, pH, and N-nitrate concentration. Indicators of organic pollution fall in the range of betameso- to alfamesosaprobic self-purification grades. Our studies show ecological significance of the Nahal Qishon as a model for a strongly disturbed aquatic ecosystem in the coastal zone of eastern Mediterranean.     

Invertebrate drift in the Dan River,Israel

The Dan river, a principal source of the Jordan River, Israel, is unusually constant in discharge (8 m³·s^–1) and water temperature (15–16 °C). The Jordan headwaters constitute the southernmost oasis of a palearctic north temperate fauna, and presumably the very constancy of the Dan contributes to its important role as a regional refuge. However, little is known of river ecology from this region. We report a twelve month study of drift, undertaken to assess diel, seasonal, and spatial patterns of the abundance of drifting invertebrates.Diel periodicity in drift was detectable but minimal. Baetidae nymphs showed a pronounced nocturnal increase, gammarid amphipods a modest, twofold increase, while dipteran larvae showed no diel variation. Seasonal variation likewise was minimal and due principally to the Baetidae, while gammarid amphipods showed no significant seasonality. The notably small diel and seasonal variation in aquatic drift in the Dan may be attributable to the extremely constant physical regime.Spatial variation was substantial. Two stations located 30 and 200 m below the karstic exsurgence of the Dan provided drift densities among the lowest reported anywhere, whereas two stations located 1 and 4.5 km downstream had more typical drift densities. A water diversion project completed halfway through the study resulted in a 50% reduction in flow at the most downstream stations, but had no discernible effect on drift.     

River Dan,headwater of the Jordan,an aquatic oasis of the Middle East

River Dan is the largest of the headwater rivers of the Jordan. The karstic exsurgence of the Dan has a seasonally stable output, a long stretch of strongly turbulent flow, stable temperature around 15.5°C and high oxygen saturation. A total of 156 taxa, mainly at the species level, were identified from the river. These species are almost exclusively of Palearctic origin. About half of the species are limited to the northernmost part of Israel. The faunal complex described, does not present any longitudinal zonation for the 5 kilometers of turbulent flow; neither does it present seasonal changes in species composition. River Dan is considered to be a post-Pleistocenic river which has an important function of refugium for a wide area of aquatic water-bodies in the area, including the presently drained Lake Hula. It is suggested that in the Illies scheme of stream classification, River Dan might represent a type of stream belonging to a ‘pseudorhithral’ along with other stenothermic warm water torrents of the tropical-subtropical climatic belt.     

Algal indicator system of environmental variables in the Hadera River basin,central Israel

Abstract

We identified 126 species of algae and cyanoprokaryotes from seven divisions in 21 samples of plankton and periphyton collected at 8 stations over the Hadera River in 2003 – 2005. The chlorophytes strongly prevail. Of these, 110 species are indicators of environmental conditions. The indicators of saprobity (Watanabe's scale) show a medium level of organic pollution. The saprobity index S (Sládecek's scale) varies from 1.73 to 2.80, corresponding to II – IV classes of water quality. The environmental pollution index (EPI) varies from 2 to 5 indicating a range of slightly to strongly polluted water of classes III and IV. The Water Ecosystem State Index, WESI = 0.6, testifies to a toxic impact on the algae in the middle reaches. The River Pollution Index for saprobity (RPIs = 2.35 – 2.42), temperature (RPIt = 17.1 in winter), conductivity (RPIε = 3.31 – 4.5), nitric nitrogen (RPI_N = 15.3), and pH (RPI_pH = 7.6 – 8.3) indicate alkaline, moderately mineralized waters with an occasional input of nitrates all year round, corresponding to classes III – IV of water quality, and the beta- to alfa-mesosaprobic self-purification zone. According to our results, the self-purification capacity of the Hadera River ecosystem is rather high. This study shows the potential of the algal bioindication method for aquatic ecosystems of Israel.     

Spring and summer macroinvertebrate drift in the Lower Mississippi River,Louisiana

Macroinvertebrate drift was sampled dielly each month at three stations across the lower Mississippi River, Louisiana. At least 134 taxa were identified from seven phyla. Total drift catches varied with respect to month, time of day, and station. Relative abundance was greatest in June and August, moderate in July, and lowest in April and May. Dipterans, ephemeropterans and trichopterans numerically dominated the catches and each tended to have its zenith in July, August and June respectively. Important non-insect groups were hydroids, oligochaetes, pelecypods and amphipods and with the exception of pelecypods, were most abundant in April. The presence of certain apparent exotic oligochaetes suggested that at least some elements of the drift may be derived from rather remote areas — perhaps even the drainage headwaters. Diel periodicity was most pronounced during the summer months of high total drift densities. Ephemeropterans exhibited strong, nocturnally — oriented diel periodicity, both at the ordinal and lower taxonomic levels, trichopterans and dipterans showed varying tendencies with respect to individual lower taxa. Catches for the dielly-periodic taxa indicated a preponderance of the bigeminus forms. But each major insect order may have had one lower taxon exhibiting the alternans pattern. The stations were decreasingly productive from right-shore to left-shore, while taxonomic richness was greater at midstream and approximately equal along the shores. But spatial patterns of occurrence varied according to months.     

Lower Paleolithic hominin ecology at the fringe of the desert: Faunal remains from Bizat Ruhama and Nahal Hesi, Northern Negev, Israel

The Southern Levant is a pivotal area for the study of hominin paleoecology during the Lower Paleolithic, because of its location on the out-of-Africa dispersal route and its significant ecological diversity. Important information has been gained by archaeofaunal studies, which usually reveal that exploitation of diverse Mediterranean environments with woodlands, marshes and lake margins, represents a dominant subsistence strategy for Lower Paleolithic hominins. Here, we present new taxonomic and taphonomic data from two sites in the southern coastal plain of the Southern Levant, at the fringe of the Negev Desert: Bizat Ruhama (Early Pleistocene) and Nahal Hesi (Middle Pleistocene). The sites preserve anthropogenic faunas, with the former signaling a marrow-exploitation strategy, perhaps related to scavenging from carnivore kills, and the latter showing evidence for primary access to fleshed ungulate carcasses. The species composition of these Northern Negev sites is unique for the Levantine Lower Paleolithic in that these sites lack typical woodland and riparian species, probably indicating an open, relatively uniform environment with patchy water sources and trees, much like this semiarid region today. Bizat Ruhama and Nahal Hesi are among the only Levantine Lower Paleolithic faunas associated with such a setting, thereby widening the known spectrum of environments exploited by hominins in the region. It is suggested that the two sites, coupled with the nearby Late Pleistocene evidence, reflect a largely stable semiarid environment on the northwestern fringe of the Negev Desert throughout much of the Pleistocene.     

汾河流域中下游植物群落物种多样性与土壤因子的关系

于2011年4~10月对汾河流域中下游33个样地128个样方的植被进行样地调查和土壤取样分析,并运用双向指示种分析（TWINSPAN）进行群落分类,用典范对应分析法（CCA）分析7种土壤因子与汾河流域中下游植物群落的分布关系,以揭示汾河流域中下游植被的物种多样性与土壤因子的关系。结果表明:（1）汾河流域中下游地区共发现植物121种,隶属33科81个属,其中以菊科、禾本科、藜科和蓼科植物最多,分别占总数的24.79%、14.05%、8.26%和7.43%,且芦苇的分布频率最高,达到49%。（2）双向指示种分析表明,汾河流域中下游33个样地分为8个群落类型（Ⅰ~Ⅷ）。（3）汾河流域中下游植物群落的Patrick丰富度指数和Shannon-Wiener指数变化趋势相似,而Simpson指数则与Patrick丰富度指数和Shannon-Wiener指数呈相反的变化趋势;Pielou均匀度指数的变化趋势与其他3个指数均不同。（4）汾河流域中下游土壤含水量、速效钾含量在不同群落类型的不同样地间的差异大部分达到显著水平,土壤养分具有比较明显的空间分布中度不均的特点。（5）汾河流域中下游地区的土壤有机质含量与物种Simpson指数以及土壤全氮与Pielou均匀度指数均具有显著负相关关系。（6）CCA排序结果表明,土壤含水量及速效磷、速效钾含量是影响植被群落分布最重要的环境因子。     

图们江下游湿地水鸟及其生态分布

于１９８８－１９９８年期间分不同季节以图们江下游湿地水鸟进行了调查研究,共调查统计到湿地水鸟９目１２科５６种。调查以野外实地考察为主,同时进行一些座谈访问和资料收集工作,数量统计采取线路统计与样方统计组结合的方法。     

全新世早期中国长江下游地区橡子和水稻的开发利用

最近发掘的浙江上山和小黄山遗址(11400—8000cal BP)是长江下游地区迄今发现最早的村落遗址。这两个遗址均出土有大量磨石, 而有机物遗存保存很少。本文对7件石器进行了淀粉粒、植硅体以及矿物残留物的初步分析, 以便检验这些方法在复原古代生计形态和器物功能研究中的可行性。鉴定出的淀粉粒包括橡子、根茎类、薏苡以及疑似菱角等, 但是没有发现水稻。在发现的水稻植硅体中, 来自茎杆和叶的密度较高, 而来自颖壳的密度较低。矿物分析表明残留物来自工具的使用以及周围的土壤基质。结果显示这些磨石曾经用于加工富含淀粉的植物和制陶用的羼和料。我们认为, 对富含淀粉并且适于长期贮存的植物特别是橡子的大量开发利用是全新世早期长江下游地区生计形态中采集策略的特征。本研究显示了淀粉粒和植硅体分析在古代生计重建中的巨大潜力。对这些遗址残留物的进一步研究将有助于我们更好地理解这一地区从采集经济到定居农耕经济的转变。     

Contribution to the taxonomy and ecology of the Azorean benthic marine algae

Algal zonation patterns were studied in two sites (Caloura, south coast and Ribeirinha, north coast) of the island of Sao Miguel, Azores. At each site two stations were studied and the transects revealed the occurrence of two distinct and well established algal zones. In the first zone, daily immersed and emersed by the tide, the algae were growing in a dense and short tangle forming a mat, referred to as algal turf. In the second zone, which was wet most of the time, the algae were larger and frondose. A list of the species of benthic marine algae occurring on the algal turf of each station is given. Of the total of 47 species found, eight are new for the Azores and another 13 species are recorded for the first time for Sao Miguel. Gigartina acicularis (Roth) Lamouroux and articulate coralline algae (Corallina oficinalis Linnaeus and Jania spp.) were the more common species. Seasonal variation of the algal turf was studied and related to mean monthly values of air and sea water temperatures, insolation and hours of light. The zonation patterns and composition of algal species were compared with those from other open rocky shores.     

First record of the Leatherback Turtle,Dermochelys coriacea,from Jordan

Abstract

The present study provides information on the ecology of four species of land snail which are distributed in the north region of the Republic of Yemen (NY). These are Eurypryxis labiosa, Euryptyxis fragosa, Zebrinops albata and Macroptychia sumarana. In addition, Revoilia bentianum and the slug Laevicaulis alte are recorded for the first time from northern Yemen and from Yemen as a whole respectively.     

Some aspects of the reproductive biology ofBarbus spp.,Capoeta damascina and their hybrids (Cyprinidae, Teleostei) in Israel

The reproductive biology and gonad cycle of three Cyprinid fish species:Barbus canis (Valenciennes, 1842),B. longiceps (Valenciennes, 1842) andCapoeta damascina (Valenciennes, 1842), in the upper Jordan River system of Israel were studied by monthly sampling over a two-year period. The reproductive activity of the three species was found to peak from January to April, mostly involving upstream migration towards spawning grounds on river beds 400–900 m above the Jordan River. Hybrids of the three species were collected in nature: in those ofBarbus canis ×Capoeta damascina, the gonads possessed both types of gametes, spermatogonia and oogonia, all of which became arrested at an early stage of development, and infertile; in hybrids of detected in nature, males had oocytes dispersed in the testis, whereas in females, the ovaries had small islets of spermatogonial tissue. In these female hybrids the oocytes ripened normally and spawning occurred.     

Green algae from the Lower Cretaceous carbonate of northern Shiraz (Zagros Mountains,SW Iran)

In northern Shiraz (SW Iran), Lower Cretaceous carbonate was studied in detail. In this study, nine species of dasycladacea algae were classified. There are different species of dasycladacea algae which belong to seven different genera: Actinoporella, Cylindroporella, Dissocladela, Heteroporella, Neomeris, Salpingoporella, Trinocladus; one species of udoteaceae belongs to Bouenia; one species of acetabulariaceae belongs to Clypeina and the microproblematicum Coptocampylodon was also seen. Among the green algae, dasycladaceae and acetabulariceae are the most frequent and udoteaceans are rare in Zagros Mountains. The genus of Trinocladus is a new record for Lower Cretaceous (Upper Albian) in SW Iran.     

Distribution,habitat and conservation status of desert pupfish (Cyprinodon macularius) in the Lower Colorado River Basin,Mexico

In order to better determine the currentstatus of desert pupfish populations (Cyprinodon macularius macularius) in the LowerColorado River Basin of Mexico, bimonthly fishsampling and habitat evaluations were carriedout from September 1996 to August 1997 in sixlocalities of Baja California and Sonora.Desert pupfish were collected using minnowseines and traps. Four sampling sites are inSonora, in shallow marginal habitats of theCiénega Santa Clara (Hunters' Camp, Outletof the Welton-Mohawk channel, El Doctor andFlor del Desierto) and two are in BajaCalifornia (Cerro Prieto and streams south ofCerro Prieto). The most abundant fish speciessampled was native desert pupfish (C.macularius, 59%) followed by sailfin molly(Poecilia latipinna, 19%), redbellytilapia (Tilapia cf. zilli, 10%) and western mosquito fish (Gambusiaaffinis, 7%). Significant temporalfluctuations in distribution and abundance ofdesert pupfish populations, as previouslyreported for these populations, was againdocumented. The main anthropogenic factorsaffecting distribution and abundance of desertpupfish populations in the Mexican portion ofthe Lower Colorado River Basin are progressivealteration of aquatic and riparian habitats, aswell as presence of exotic fishes that havecaused the displacement or elimination ofnative fish populations. Both habitat andpresence of the desert pupfish populations inthe study area are controlled by theperiodicity, quality and volume of dischargesinto the Mexican portion of the basin from theUnited States.     

汉江支流堵河鱼类群落结构及多样性

基于堵河2018年6月-2019年5月渔获物,分析了鱼类群落组成及变化、优势种以及群落多样性时空分布特征,讨论了外界环境扰动作用对鱼类群落结构和生物多样性的影响.结果 表明:调查期间共采集鱼类38种,分属4目8科,其中鲤形目鱼类最多(26种),占总种数的68.4％.群落优势种为鳙(Aristichthys nobili...     

The ecology of some Benthic Oligochaeta from the Paraná River,Argentina

Simple and multiple correlations among physical and chemical parameters and densities of the dominant Oligochaete species were calculated for various channels of the middle Paraná valley and its tributaries. Paranadrilus descolei Gavrilov, 1955, was observed in rivers with average depth and current velocity, mud-clay sediments, and low conductivity. Tubifex tubifex f. blanchardi Vejd., 1891, was found in channels of low depth, current velocity and discharge but with high conductivity. Limnodrilus hoffmeisteri Claparède, 1862, and Aulodrilus pigueti Kowalewski, 1914, were ubiquitous species. Narapa bonettoi Righi and Varela, 1983, was typical of rivers highest in depth, current velocity, and discharge with sandy sediments and low conductivity.     

黑河下游额济纳绿洲植物群落特征与物种多样性研究

根据53个20 m×20 m样方调查资料,对黑河下游额济纳绿洲植物群落特征及物种多样性进行研究.结果表明:(1)调查样方的植物种类组成成分简单,科属组成较为分散.共有12科26属28种,以藜科、菊科为主,分别占21.43%和14.29%.种类优势现象明显,重要值>10的物种主要有胡杨、梭梭、柽柳、白刺、沙拐枣、苦豆子等;(2)不同植物群落类型的物种多样性指数均较低,且存在较大差异.以重要值计算的Margalef丰富度指数(Rm)介于0.027 3~0.567 7,Simpson多样性指数(Ds)介于0.677 8~0.999 3,Shannon-Weiner多样性指数(H′)介于0.098 2~0.367 3,Pielou均匀度指数(J′)在0.078~0.383之间,表明荒漠绿洲植物群落的结构简单、组织水平低;(3)样方统计的物种多样性指数纬向变化没有经向变化趋势明显,Ds和H′的纬向变化在42.02°N附近存在一个明显的高值区,经向变化呈先增后减的趋势,J′纬向变化与Ds和H′变化趋势较为一致,经向变化趋势不明显,呈连续波动的复杂变化特征.     

The Epipelic Algal Flora of the River Wye System,Wales, U. K. 2. Algal Phyla and Species Population Dynamics

The Bacillariophyta dominated over the other phyla and were mainly recorded in high densities during summer and autumn. The Chlorophyta and Myxophyta (Cyanobacteria) were represented by coccoid forms and by non-heterocystous, filamentous forms, respectively. Both were mainly recorded during summer and mostly absent during winter. Other phyla were occasionally recorded in low densities; the Chrysophyta being found in the River Elan and at one site on the River Wye during June 1980. Their members were considered as “contaminants” or “fall-out” from other communities. Pennate diatoms were the most “constant” species and either showed a general upstream or downstream increase or a general distribution throughout the study area. Populations of the same species colonising both sediments and stones were not correlated or insignificantly correlated with each other at most stations. It was concluded that sediments were unsuitable for algal colonisation. The River Elan and upper Wye were rated as oligosaprobic, the River Ithon and lower Wye as β-mesosaprobic and the River Lugg as α-mesosaprobic.