西藏唐北地区湖泊动态及空间格局预测

本研究评估了西藏唐古拉山以北地区(唐北地区)湖泊动态并预测了湖泊空间格局变化.使用面向对象分类和光谱角向量变化检测方法生成了2000-2015年西藏唐北地区每5年一期的生态系统分布数据.以此为基础,分析了湖泊与其他生态系统之间的转换和空间格局特征,评估了湖泊空间格局的动态及其与相关自然地理因素的关系.通过增强回归树识别了不同因素对湖泊动态的贡献,使用GEOMOD模型预测了湖泊到2030年的空间变化.结果表明:唐北地区在2000-2015年间湖泊增加了14.2%,是唐北地区生态系统变化的主要形式之一.区域内15个面积大于10 km2的湖泊有10个增加,另有5个减少,且缩减量较低.通过空间格局分析发现,唐北地区湖泊斑块表现为面积和数量同时增加,大斑块面积比重略有上升.扩张幅度高的湖泊多分布于海拔高、坡度大、温度低、降水少、距离冰川近的区域.位于现有湖泊周边、温度低、降水少、坡度小的区域转变为湖泊的几率较高.根据过去15年的趋势,到2030年,唐北地区湖泊将继续增加119 km2,主要变化形式从大湖扩张转变为小型水面扩张.     

The realigment of the orchid flora in the mountain range of Guamuahaya,Cienfuegos, Cuba

The present study of the Orchidaceae family was carried out in Guamuahaya’s mountain range, from 2000 to March 2013. Fifteen districts were explored after 33 expeditions in the Province of Cienfuegos. Ninety two plant species were identified in the studied area, taking into account the ecological parameters of the mountainous areas of Cienfuegos and Cumanayagua municipalities.     

The impact of predation by the powerful owl,Ninox strenua,on a population of the greater glider,Petauroides volans

Powerful owls were frequently observed during a study of the ecology of a community of arboreal marsupials in south-eastern New South Wales. For about 17 months the population of greater gliders in the 100 ha study area appeared to remain ‘stable’ at more than 80 individuals. In the following 46 months, the population declined to about one-tenth of its previous level. The forest in the study area was unlogged and remained undisturbed during this period. The frequency of sightings of powerful owls holding captured greater gliders, and of observations on the ground of tails and bodies belonging to greater gliders, and the unaccountable disappearance of 9 out of 11 individually marked greater gliders in the study area, suggest that the observed decline in the population of greater gliders was due to predation by the powerful owl. Powerful owls were not detected in the study area during the first 12 months or the last 21 months of the study. It is suggested that powerful owls forage by concentrating their activities in pockets of their large home range until they reduce the populations of their preferred prey below limits where it becomes difficult to catch the remaining animals. If preferred prey are available elsewhere, powerful owls probably move their centres of foraging activity to these pockets and harvest them before moving on to the next pocket of their range.     

The role of macrophytes,especiallyZostera marina,in the carbon cycle of Lake Grevelingen (IV)

Summary Macrophytes in Lake Grevelingen comprise macroalgae (Ulva, Enteromorpha, Chaetomorpha) and eelgrass (Zostera marina). In terms of production of organic matter far out the largest share comes from eelgrass. Eelgrass showed an enormous increase after the closure of the dam in 1971: in 1968 the phanerogam covered an area of 1200 ha, and in 1978 this area was 4400 ha (Fig. 3).     

Physicochemical and biological characterization of the water quality in the Piedras Blancas basin, Antioquia, Colombia] [In Process Citation

From April to December 1996 a limnological study was carried out in 17 streams near Medellin, in order to stablish their water quality. The area is located in Piedras Blancas Park (6 degrees 8' 20"N, 75 degrees 30' 20"W) SE of Medellin at 2,400 m altitude. Three sampling periods, encompasing wet and dry season were selected: April-May, August-September and October-December. For qualitative collection methods hand screen and D-net were used. Each station was intensively sampled to collect most macroinvertebrates in all types of habitat. The area sampled in each station was 6 m2. Physicochemical variables in general showed small fluctuations along the study; only conductivity and total dissolved solids exhibited significant changes, all related with high precipitation in the wet season. Macroinvertebrate community consisted of 113 genera, 63 families and seven phyla. Trichoptera was the most abundant group. The results indicate that the freshwater ecosystems in the study area present a high water quality corresponding to a oligo-mesotrophic system.     

Individual variation in homing tendency in the European minnow, Phoxinus phoxinus (L)

The ability of minnows to accept home ranges in aquarium tanks was confirmed. Observation of individually marked fish indicated that there was variation in the tendency for individual movement. Minnows which spent the majority of their time at home showed differences in the number of forays out of their home area. Non-homing fish also varied, from individuals which moved a lot and showed no preference for any area, to others which spent most of their time in a strange area and made few forays.     

Radioautographic study on the localization of an anti-allergic agent, tranilast, in the rat liver

In order to demonstrate the localization associated with metabolism of an anti-allergic agent, Tranilast, in the liver, light microscopic radioautography of the liver was performed. Rats were administrated orally with 3H-Tranilast, and were sacrificed at 15 minutes to 24 hours after the administration. The livers were taken out and fixed, embedded and processed for light microscopic radioautography. 3H-Tranilast was absorbed rapidly, and the radioactivity in the liver increased and decreased within several hours. The number of radioautographic silver grains reached a maximum 3 hours after the administration. From 1 to 6 hours after the administration, the silver grains decreased from the portal area toward the central area. Seventy to 80% of all silver grains on the hepatocytes were retained in the cytoplasms of the hepatocytes at any experimental period. From these results, it was concluded that the localization of radioautographic silver grains was associated with Tranilast uptake of hepatocytes in each hepatic lobular compartment and that the metabolic process from uptake to excretion of Tranilast took part in the hepatocytes in each hepatic lobular compartment.     

Some observations on the seasonal distribution of dab,Limanda limanda, in the southern North Sea

The seasonal changes in the population structure of dab were observed in intervals of four to six weeks from January 1993 to November 1994 at a fixed station northwest of Helgoland. The sex distribution was characterized by a reduced number of males during autumn and winter. In the autumn of both years, an immigration of large females was evident. During long periods in spring and summer, the population structure remained relatively constant. The observations indicate that dab in the Helgoland region carry out a seasonal migration between coastal waters and the sampling area. Seasonal changes of the population structure occurred at a relatively slow rate.     

Re-examination of the lower stratigraphy in the classic section, limeworks site, Makapansgat, South Africa

At the end of Member 2 times, remnant mammillary-form stalactites in the roof and wall contacts show that an irregular wedge-shaped space existed from the Classic Section out to the Cone area. It was into this space that hyenas and other denning animals were able to gain access from an as yet unfilled Cone area. During the mining operations of the 1920’s, Eitzman (1958) recollects entering an impressive bone breccia resembling a charnel house. We suggest that it is most probable that the Grey Breccia corresponds to his main breccia as only the area on top of Member 2, between the dolomite walls, roof and stalagmite boss has the required volume. It also lies at the end of an incline first dug by the miners, (still in existence), and at the end of which he was able to note some of the deposits. The bone breccias at the same level at the back of the Cone suggest that other dens were created at about this time. As the roof continued to retreat upslope and more material was washed in or fell in from the surface so more sediment was winnowed into the back of the Cone. At some stage this allowed prey animals to enter the Cone area and gain access between the speleothem barrier to the area of the Classic Section. As most Australopithecine fragments came from this breccia, it seems likely that, as with Swartkrans, the hominid fragments are the result of predation. Then as sediments continued to wash into the Cone area, the Classic Section and the back of the Cone became inaccessible for denning purposes. Large speleothem remnants embedded in sediment starting part-way up the Cone shows that a roof continued to exist in this area for some time. In fact, even today, although bits of speleothems can be found in the eroded hardened surface sediments there are few, if any, dolomite blocks. We presume that they were removed along with the upper part of the infilled, cavern along with the country rock as the surface continued to erode. Although it may not be possible to reconstruct a complete strati-graphic sequence involving the whole of the site, we have presented summary of evidence here that shows it is possible to trace stratigraphic relationships from the base of the Ancient Entrance to the top of the Cone and which includes the Grey Breccia and the two other bone breccias. Present work is focussed on completion of a new chronology by comparing our site magnetostratigraphy with the global polarity timescale. The speleothem deposition today in any of the caves of the Makapansgat area, with its annual rainfall of about 700mm, is extremely low. It is commonly recognised by karst geomorphologists (eg, Ford and Williams, 1989) that massive deposits of speleothem are characteristic of humid tropical to semi-tropical karsts. Hence, at the time of their formation some 3 Ma or more ago, the massive speleothem deposits are evidence for a warmer, and certainly a much wetter, climate than that of today.     

The diversity of life-form type, habitat preference and phenology of the endemics in the Goa region of the Western Ghats, India

Aim To carry out (1) a floristic survey of endemic flowering plants of the Western Ghats occurring in Goa, (2) identify their habitat preference and diversity of life‐form type, (3) observe flowering phenology of the endemics and (4) to correlate factors that affect their phenological pattern. Location Goa state is located between 15°48′ N and 14°53′54′′ N and 74°20′13′′ E and 73°40′33′′ E, in the northern part of the Western Ghats, India. Method A list of endemic plants from the study area was prepared using available floristic works and checklists of endemic plants of India. Based on preliminary field observations carried out in the study area, major habitats such as plateaus, moist deciduous forests, semi‐evergreen forests, evergreen forests and mangroves were identified for the subsequent intensive survey of endemics. Voucher specimens for all the endemic species were collected, processed using conventional herbarium techniques and deposited in the Herbarium, Department of Botany, Goa University. Species were identified using local and regional floras and their identity was confirmed at various herbaria along the Western Ghats. Data on their life‐form types, habitat and phenology was recorded in the field. Phenological observations were made every fortnight. A computerized data base was generated incorporating details on their life‐form type, phenology and habitat. Results A floristic survey of endemic plants of the Western Ghats in Goa resulted in the collection of 113 endemic species. Life‐form analysis reveals that herbaceous endemics are the most dominant followed by trees, shrubs and climbers. Plateaus in the study area harbour the largest number of endemic species, especially herbs. Endemic trees are distributed in the semi‐evergreen and evergreen forests. Endemic species in the study area show different peak and lean seasons of flowering depending on their life‐form type, habitat and ecological factors like temperature and rainfall/moisture content in the soil. Main conclusions The plateaus in the northern part of the Western Ghats are unique, being species rich with herbaceous endemics. These ephemerals are closely associated with the rainfall patterns thus; any change of moisture regime over the long‐term will have an impact on the distribution of these endemics.     

鳗草在荣成天鹅湖不同生境中生长的适应性

鳗草在北半球温带海域广有分布,受到不同程度的人为干扰和环境胁迫,海草床面积急剧退化.为探讨鳗草对不同环境胁迫的适应性,于2014年11月—2015年10月对荣成天鹅湖草床的潮间带和潮下带的斑块区、鳗草草场边缘和鳗草草场内部4个生境的鳗草形态和繁殖能力进行了研究.结果表明: 叶长、叶宽、节间长度/直径、地上生物量/地下生物量和分枝频率在不同月份和生境间差异显著,其中除了分枝频率最大值出现在草场边缘(88.4%)外,其他各项指标的最大值均出现在草场内部(分别为78.54 cm、7.93 mm、7.03和3.88).地上生物量/地下生物量的可塑性指数在各站位均较高(0.77～0.92),叶宽的可塑性(0.41～0.64)略小.不同生境中单株鳗草佛焰苞数差异不显著,而单位面积的佛焰苞数差异显著,在草场内部偏向于克隆生殖,而在人为干扰较大的斑块区倾向于有性生殖.     

Evaluation of industrial, hospital and domestic wastewater genotoxicity with the Salmonella fluctuation test and the SOS chromotest

An evaluation of the genotoxic potential of different wastewaters collected in the Rouen area was performed with the SOS chromotest (on Escherichia coli PQ37) and the Salmonella fluctuation test on Salmonella typhimurium strains TA98, TA100 and TA102 with or without metabolic activation. The samples were taken during two 1-week periods, one in January and one in April 2003. Six sites were selected for wastewater sampling in order to allow a comparative study between an area of mixed discharge (industrial, hospital and domestic) and an area of primarily domestic discharge. Out of a total of 71 daytime samples tested, 46 (65%) were positive in at least one assay: 22 samples out of 33 in January (67%), and 24 samples out of 38 in April (63%). The two genotoxicity tests have different sensitivities. Indeed, the Salmonella fluctuation test allowed the detection of 56% of the samples as genotoxic in January (18 out of 33), and 63% in April (24 out of 38) while the SOS chromotest allowed the detection of 18% of the samples as genotoxic, whatever the sampling period. The samples collected in domestic wastewater are at least as genotoxic as the samples collected in mixed wastewater. The possible source of the detected genotoxicity (industrial, hospital or domestic) is discussed. The results of this study show that the different types of wastewaters present a genotoxic risk. Additional studies should be undertaken in the analytical field in order to try to identify and quantify the compounds responsible for the genotoxicity. This difficult task will be necessary in order to identify the sources of toxicants and thus to take preventive and/or curative measures to limit the toxicity of the wastewater.     

福建省长汀县河田盆地区近35年来地表裸土变化的遥感时空分析

福建省长汀县河田盆地区是中国南方最典型的红壤水土流失区之一,当地人民和各级政府一直为治理该区的水土流失进行着不懈的努力.利用遥感技术对该区1976年以来地表裸土分布的时空变化进行了分析,基于所提出的双重遥感指数法对该区的裸土信息进行提取,查明了该区地表裸土分布的时空变化情况.研究表明,该区近35年的治理已大大减轻了地表的裸露程度,地表裸土面积从1976年的159.17 km2锐减到2010年的51.98 km2.在3个不同的观察时间段里,裸土面积的变化呈现逐次减少、减速加快的趋势,客观地反映了该区水土流失治理的3个重要历史时期和政策所产生的效应.     

百色田东百渡旧石器遗址发掘简报

百渡遗址位于右江南岸,广西田东县附近, 在2002年发掘了700m2, 出土约1500件石制品。石制品类型包括石器、砾石、石锤、石核、石片、断块和碎片; 原料均为砾石, 岩性以砂岩为主; 石核包括单台面、双台面和多台面三种; 打片和加工石器均以锤击法为主, 单面加工; 石器类型有砍砸器、手镐、刮削器。从石制品的特征和组合看, 该遗址既是古人类的石器制造场所, 又是生产、生活的地方。其石制品与百色盆地第4级阶地网纹红土中的石制品有一定的差别, 表现出比较进步的性质。通过地质、地貌和出土遗物的对比分析判断, 遗址的年代可能为中更新世后段。     

Eggs and larvae of the 'curvina' Plagioscion squamosissimus (Heckel, 1840) (Osteichthyes, Sciaenidae) in the Baia River, Mato Grosso do Sul State, Brazil

The aim of this work was to study the eggs and larvae of the‘curvina’, specifically the examination of spatialand temporal variation, location of spawning and dispersal groundsand verification of the relationship between occurrence andenvironmental variables. Sixteen collection sites were establishedin the Baía River, Brazil, and grouped into four areas.Collections were carried out between February 1999 and April2000. Spatial and temporal variations were analysed using ANOVA.Identification of the spawning and dispersal grounds was carriedout using development stage distribution. The relationship betweenoccurrence and the environmental variables was determined usingPrincipal Components Analysis (PCA) and Pearson correlation.The eggs were found in every area practically every month, almostexclusively in the initial embryo stage, while the larvae occurredin every area mainly between October and April. The correlationbetween PCA scores and organism occurrence demonstrated thatthe highest catches occurred when the values of temperature,water level and rainfall were high and those of dissolved oxygenand pH were low. This specie spawns and develops in lentic areas,and the lotic stretch serves as a dispersal route through whichthe eggs and larvae are transported.     

Population structure and ecology of the African buffalo (Syncerus caffer Sparrman, 1779) in Chebera Churchura National Park,Ethiopia

An investigation of population structure and ecology of the African buffalo (Syncerus caffer Sparrman, 1779) was carried out in the Chebera Churchura National Park, Ethiopia during the wet and dry seasons of 2005–2006. Sample counts of African buffaloes were carried out in an area of 1,215 km². The estimated population of buffalo was 2,617 individuals. Males comprised 35.0%, while females 52.8% of the population. The remaining 12% of the population was young of both sexes and of all ages of unknown sex. It was difficult to categorize the young into male and female in the field, as their primary sexual characteristics were not easily visible. Male to female sex ratio was 1.00 : 1.51. Age structure was dominated by adults, which constituted 72.06% of the total population. Subadults comprised 22.02%, and young accounted for 5.9% of the population. Larger herds of up to 27 individuals were observed during the wet season and smaller herds of eight individuals during the dry season. The mean herd size during wet and dry seasons was 24.81 and 7.77, respectively. The African buffaloes were distributed in four habitat types such as grasslands, woodlands, montane forests and riverine habitat in the study area. They were observed more in the riverine vegetation types during the dry season. Relative abundance of food resources, green vegetation cover and water availability in the area were the major factors governing their distribution in the present study area. They spent a greater proportion of the time in feeding and resting/ruminating activities. On the average, 49.7% of the daytime was spent in feeding, and 38.75% of the day on resting (lying down and standing). Morning and the late afternoon activity peaks were more pronounced during the dry season than the wet season.     

A SCUBA-diving investigation of Baltic herring (Clupea harengus membras L.) spawning grounds in the Askö-Landsort area, northern Baltic proper

In a spawning area survey in the Askö area, northern Baltic proper, undertaken in the beginning of summer 1978, 100 randomly established and sampled transects were studied by diving. Herring spawn was found at 45 of the transects. The eggs were usually found on Pilayella littoralis , a filamentous brown algae, at the more exposed transects. Eggs were only found down to a depth of 11 m. In a neighbouring oil spill area spawn were found at only four out of 20 transects. Of eggs taken to the laboratory for hatching, 54% of those from the unaffected area hatched but only 25% of those from the oil spill area.     

Land-use and resource conflicts in the Okavango Delta, Botswana

This study assesses land-use conflicts in the Okavango wetland ecosystem. A survey of the livelihood activities of a sample of four villages has been carried out and a stakeholder approach used to identify and analyse the key actors involved in resource competition and conflicts in the area. Traditional and emerging stakeholders were identified and found to be in conflict not only with each other but within themselves. Institutional policies on land use in the area are not properly harmonized, and there has been a top-down approach to development planning and implementation of development programmes. As a result, land-use conflicts have escalated in the area. The Okavango Delta Management Plan adopted in 2007 should integrate and harmonize all the land-use policies, and land management in the area.     

Changes in Melaleuca forest density on the Magela floodplain,Northern Territory,between 1950 and 1975

The stability of the Magela floodplain prior to the development of uranium mining at Ranger, in the Magela catchment, was estimated by comparing aerial photographs taken in 1950 and 1975, using the density of Melaleuca swamp forest as an index of change. The 1975 photographs were interpreted in the light of a ground survey carried out in the dry season of 1976. There was no increase in the area occupied by Melaleuca trees, indicating that infilling of perennial swamp and plant succession were not significant agents of change in this period. Thirty-eight per cent of the forested area suffered a significant decrease in tree density: fire, wind and buffalo are among the probable causes, and these hazards should be taken into account in monitoring the effects of the uranium mining.     

Characterization of the water quality of dam lakes on Shikoku Island, Japan

This study clarifies the distribution and variation of bioelements in dam lakes of the Shikoku region, Japan. The survey was carried out from 2002 to 2003 on three dam lakes in the Shikoku Mountains with high precipitation levels and on three dam lakes in the Sanuki mountain range with low precipitation levels. By the conventional classification for eutrophication, the dam lakes in the Shikoku Mountains were classified as oligotrophic to mesotrophic, whereas those in the Sanuki mountain range were classified as mesotrophic to eutrophic. Furthermore, for the dam lakes in the Sanuki mountain range, it was indicated that the amount of precipitation directly and indirectly affected lake water quality, such as high nitrogen concentration, low dissolved oxygen concentration, and increase in primary production. Especially, in a hypertrophic dam lake, during the period of low precipitation the surface water flowed out and the water under the thermocline, with no dissolved oxygen, appeared on the lake surface. As a result, the anaerobic environment extended across all the layers. Because a compulsory water-level operation was carried out in the dam lake, it was considered that the effect of the hydrological environment in the catchment area on the dam lake was relatively large in comparison with that in natural lakes.