Riverside Vegetation Research Articles

Children's perceptions of river landscapes and play: what children's photographs reveal

The insights that children's photography can provide into children's perceptions of river landscapes and play opportunities are focused upon, based on an analysis of over 500 photographs and comments generated during visits to two London rivers by children aged nine to eleven from three nearby schools. In their photographs, the children recognized the aesthetic appeal of specific natural features of the river landscapes, particularly trees. Some also appreciated broader river landscape ‘views’. The rivers themselves were seen as littered and polluted. Dangers were identified, but these were not seen as unmanageable. The children recognized the special character of the rivers as play places affording varied, adventurous and manipulable play opportunities, but wanted cleaner, safer, more accessible and managed rivers. Some differences were found in the responses of boys and girls and in the children's responses to the two rivers. The urban children taking part in the study showed little understanding of the functions that living and decaying riverside vegetation might have in river ecology, indicating a need for more environmental education.

Holocene palaeoenvironmental changes in southern France: a palaeobotanical study of travertine at St-Antonin, Bouches-du-Rhône

Travertines are carbonate deposits formed generally during temperate climatic periods. They usually present a succession of travertinous units and detrital sedimentary levels containing leaf impressions and charcoal, respectively. The travertine of St-Antonin was formed during the Holocence in accordance with this model; snail shells and archaeological material have also been preserved, essentially in detrital levels. An interdisciplinary investigation combining two palaeobotanical approaches (identification of leaf imprints and charred wood) has been carried out to identify vegetation changes, at a local or microregional scale during the travertine formation. Our results were compared with those of previous malacological, geomorphological and archaeological studies. The Preboreal and Boreal sequence of the travertine shows evidence of a reduction of the riverside vegetation correlated with the establishment of a mesophilous vegetation dominated by the pubescent oak (Quercus pubescens). During the Boreal–Atlantic transition, the vegetation structure changed slightly under anthropogenic influence. From the Atlantic to the first part of the Subboreal, vegetation seems to have been profoundly affected by intensive human exploitation. This process has broken up the forested area into different plant communities and favoured the dominance of heliophilous and thermophilous species.

Diet of Juvenile Varanus niloticus (Sauria: Varanidae) on the Black Volta River in Ghana

Published accounts of the diet of Varanus niloticus suggest that it is a generalized feeder, eating a wide range of invertebrates and vertebrates that are caught by hunting and scavenging (reviewed by Losos and Greene, 1988). Examination of the skull has suggested an ontogenetic change in diet from a generalized feeder to one specialized for molluscivory (Rieppel and Labhardt, 1979), but there is no direct evidence of a high degree of molluscivory in this species. Little is known about the diet of juvenile V. niloticus, nor of the of most other Varanus species. Schmidt (1919) examined nine juvenile V. niloticus collected in Zaire and reported that only three contained food (mantid, grasshopper, frog, four slugs, crickets and unidentified insects). Auffenberg (1994) examined the stomach contents of 92 juvenile V. bengalensis from various locations and found them to be entirely insectivorous, feeding mainly on hymenopterans and coleopterans. His study suggested animals from Pakistan accumulated large amounts of fat in the first few months of life preceding a period of fasting. Varanus niloticus is heavily exploited throughout Africa for its meat and skin (Luxmoore et al., 1988), but there have been few ecological studies of the animal on which to base conservation strategies (Lenz, 1995). This study investigated the feeding ecology of young V niloticus by examination of diets and fat bodies in a sample taken from a 12 km stretch of the Black Volta River. In this study juveniles are animals of the youngest age class (probably no more than four months old), and adults refers to all other age classes. Knowledge of the diet of juvenile monitor lizards is of particular interest because very little is known about the ecology of the of any Varanus species. I report on the alimentary contents of 43 juvenile [mean SVL = 143 + 2.7 mm (SE); mean mass 41 + 2.4 g] and five adult (mean SVL 390, + 32.7 mm; mean mass 1134 + 373.8g) V niloticus, caught on the Black Volta River between Batoo village (8?17'N, 2?15'W) and Bope camp (8?22'N, 2?17'W) between 929 July 1996, and deposited in the Cape Coast University Museum, Ghana. Animals were collected by canoe as they lay in riverbank vegetation. Alimentary tracts of preserved animals were opened and all items removed. Gut contents were rinsed into a strainer with mesh size of approximately 1 mm2 and examined under low-power magnification. Identifiable fragments were recorded and identified to order. Prey were classified according to residence in the stomach or alimentary tract (referred to in this work as lower gut), depending on whether the bulk of the item lay proximal or distal to the pylorus, respectively. Recognizable fragments other than single limbs were recorded as prey items. Intact prey items were TABLE 1. Diet of juvenile Varanus niloticus (N = 43), expressed as percentage of total number of prey items.

Influence of Naturalized Plants on the Riverside Vegetation of the Lower and Middle Reaches of the Todai River in Japan's Southern Alps

南アルプス仙丈ヶ岳に源を発する戸台川の河辺はトダイアカバナ, カワラニカナ等多くの絶滅危惧種の生育地として保全上重要な地域である。しかし近年, 帰化植物の侵入, 定着がみられ, これら絶滅危惧種への影響が懸念されている。本研究では, 戸台川河辺植生の現状, 特に帰化植物定着の絶滅危惧種への影響を明らかにすることを目的とし, 中, 下流域において植物相及び群落調査を行った。最下流部の帰化率は約12%であったが, 一般都市河川の帰化率約20%と比較すると, 山岳河川としては低い値ではないと考えられた。また帰化植物のフサフジウツギ等は絶滅危惧種のカワラニガナ, トダイアカバナのハビタットと重複することが示唆された。

WOOD CHARACTERISTICS OF AMAZON FOREST TYPES

The Tambopata region of the southern Peruvian Amazon supports a high diversity of both woody plants and forest types. Woods collected from low riverside vegetation, floodplain forest, clay-soil forest on an upper terrace, sandy-soil forest, and swamp forest provide an opportunity to test for significant differences in quantitative anatomical characters among forest types. Vessel-element length in floodplain-forest trees is significantly greater than in the other forest types. Specific gravity is lower in the two early-successional associations (low riverine forest and mature floodplain forest). Vessel diameter and density do not show significant differences among forest types and may be responding to overall climate controls. These two characters, however, show a pattern of variation within a transect extending back from the river along a gradient of increasing substrate and forest age; in addition, sites characterized by frequent flooding or presence of standing water lack vessels in the wider-diameter classes. The six characters analyzed show distributions that are, with the exception of wood specific gravity, significantly nonnormally distributed, a consideration that may be important in representing characteristics of assemblages of taxa. The degree of variability seen in some of the quantitative characters shows the importance of either basing analysis on adequate sample sizes or identifying robust indicators that can be used with small samples.

Analysis of floristical and environmental gradients in the longitudinal profile of the Loire (France). The use of riparian plant species for a biotypological river‐zone classification

AbstractThe composition of riverbank vegetation at the French Loire was sampled in regular intervals along the longitudinal river profile. Distribution and abundance if 58 selected species of the willow and poplar woodlands, reed beds and adjacent therophyte communities are described from source to estuary.The longitudinal profile of the Loire can be divided by key species groups into four floristically and ecologically defined sections. Their boundaries mainly fall together with changes of water regime characteristics.The connections between species arrangement and major environmental factors (soil and water parameters) are investigated exemplarily for Therophyte communities colonizing riverbanks. The change of species composition (mathematically expressed as “floristic change index”) along the river shows a highly significant monotounous trend and is correlated with changes of pH and electrical conductivity of the soil.

Possibility of the use of Vegetation groin

There are much vegetation in a river bank Vegetation has a role of protecting banks as good. On the other hand, it has a bad role of being rose the water level.So, we should make a river course planning which is desirable for both of the river environment and flood control by using vegetation.In this paper, vegetation is attempted to use as a groin. It is experimented by a curved channel withmovable bed and investigated the flow and bed topography around the vegetation groin, and considered about the possibility of vegetation use as a groin.

Riverside vegetation and gene flow among the Japanese macaques' populations: A speculation from case studies in the Hyogo prefecture

Riverside vegetation and gene flow among the Japanese macaques' populations: A speculation from case studies in the Hyogo prefecture

A-3 川岸の被覆植物除去がコガタハマダラカ幼虫の発生密度に与える影響

A-3 川岸の被覆植物除去がコガタハマダラカ幼虫の発生密度に与える影響

A Comparison of Species Richness and Traits of Riparian Plants between a Main River Channel and Its Tributaries

Summary1 We examined differences in species richness and frequencies of vascular plants in the riverbank vegetation between the main channel of the Vindel River system and seven of its tributaries ...

The Purple-crowned Fairy-wrenMalurus coronatus. I. History, Distribution and Present Status

The two subspecies of Purple-crowned Fairywrens Malurus coronatus coronatus (Kimberleyan) and M.c. rnacgillivrayi (Carpentarian) occupy very restricted riverside vegetation across the Wet-Dry tropics of northern Australia between the 400 mm and 1000 mm isohyets; they are separated by 200 km of unsuitable habitat. The history of settlement, land degradation and the current status of these birds is dealt with in five localities. The Kimberleyan subspecies is estimated to be below 7000 individuals, to be vulnerable and in need of conservation measures. The Carpentarian subspecies is at least twice as numerous and is not threatened at present; its future status will need monitoring because of its restricted habitat. In the past decade several new national parks that are strategically well placed for populations of M. coronatus have been gazetted. Even more importantly, land management appears to be moving out of the exploitive, habitat degrading stage towards practices that minimise erosion and maintain the riverside as a renewable resource. This should benefit the survival of the species, especially M. c. coronatus.

Télédétection et connaissance des ripisylves / Remote sensing and knowledge of river bank vegetation

FRE : Landsat ! Spot ! forêts humides ! ripisylve ! étangs ! marais ! haies ! environnement

Precociously developing individuals in populations of chickweed [Stellaria media (L.) Vill.] from different habitat types, with special reference to the effects of weed control measures

summaryLong‐term weed control in gardens and arable areas is likely to be a potent selective force favouring precocious development of annual weed species. In an experiment with Stellaria media (L.) Vill., we grew progenies from open‐pollinated seed of a number of seed‐parents collected from 12 British populations of five habitat types. We raised plants in a temperate glasshouse and a garden plot, to see if plants from areas subject to weed control ‐gardens and arable fields – had a quicker rate of development from germination to flowering and fruiting than plants from habitats subject to less weed control (waysides) or no weeding pressure (seasonally exposed river sediments and bird colonies).Comparison of the behaviour of plants in the glasshouse and out‐of‐doors revealed a broadly similar pattern of behaviour. However, for some, but not all seed‐parents, rate of development was different in the two sets of conditions.In conformity with hypothesis, plants from one of the gardens were quick to reproduce, but plants from Ness Botanic Garden and arable fields were more variable than expected. Plants from less well weeded and non‐weeded sites did not conform to expectation. Plants from waysides were quick to reproduce, so too was much of the material from a bird colony on the island of Skomer. While some late‐developing plants were detected from a second bird colony (Fame) and from exposed river sediments by the Tweed and Manifold, we found a small number of precocious and some intermediate individuals in the progeny of some seed‐parents.It is possible that bird colonies and exposed river sediments are heterogeneous habitats, in which there are niches where ‘native’ variants with different rates of development are at a selective advantage.However, there is another explanation of our results. First, we discovered that, while some of the seed‐parents were probably behaving as homogeneous lines for rate of development, others show ed segregation, providing evidence that a degree of outcrossing is possible in populations of Stellaria. Secondly, there is evidence that human activities have led to habitat disturbance in and around the bird colonies and riverside vegetation we have studied. Our findings are consistent with the hypothesis that, gene flow by pollen and/or seed of precocious weedy plants has occurred in these man‐disturbed sites, leading to different patterns of variation involving hybridization between ‘introduced’ precocious plants and ‘native’ slow‐developing variants.

The effects of litter displacement on riverbank vegetation

The hypotheses that litter deposition on riverbanks would depend on riverbank features and that litter mass would affect riverbank vegetation were tested by sampling vegetation, litter, and soil along a seventh-order stretch of the unregulated Vindel River in northern Sweden. Sampling was carried out within a horizontal litter gradient at the top of the riverbank where most of the litter deposition occurs. The amount of leaf litter left on the riverbank after flooding was significantly correlated (P < 0.05) with soil organic matter. In contrast, wood litter mass and total litter mass were not correlated (P > 0.05) with riverbank features such as soil organic matter, riverbank slope, or stem density. Species richness, species diversity, and the proportions of stemmed and nonstemmed species showed quadratic relationships (P < 0.05) with leaf litter mass, whereas ground vegetation cover decreased monotonically (P < 0.05) with increasing leaf litter mass. Tall, stemmed species were most frequent at eroded sites with low amounts of leaf litter and at sites where leaf litter had accumulated. In contrast, the highest proportion of low-growing species was found at sites with intermediate leaf litter masses. Community characteristics such as species richness, species diversity, and the proportions of stemmed and nonstemmed species (but not ground vegetation cover) were less strongly correlated with wood litter mass and total litter mass. Linear equations explained about half of the variation in ground vegetation cover along gradients of wood and total litter masses. Density and richness of seeds increased with increasing litter mass. We discuss the litter effects in terms of productivity and disturbance and conclude that flooding in pristine rivers may exert a considerable influence on riverbank vegetation as a result of litter displacement.

Vertebrate conservation in Ankarana special reserve, Northern Madagascar

The Ankarana Massif is a ‘Réserve Spéciale’ of 18 220 ha in northern Madagascar, containing a wide range of biotopes including pinnacle karst, dry wester forest, semi-evergreen canopy forest, savannah, caves and riverside vegetation. This paper clarifies the conservation status of the reserve and the status of some of the rare endemic species found there. The taxa considered include: crowned lemur Lemur coronatus, Sanford's lemur Lemur fulvus sanfordi, white-breasted mesite Mesotornis variegata, and several species of locally endemic reptiles. A small area of semi-evergreen forest in the centre of the reserve holds one of the highest densities of primates known, as well as a population of white-breasted mesites (otherwise known only from two sites worldwide), and six locally endemic and seven regionally endemic species of reptiles. Data from the ‘Réserve Spéciale’ of Analamera, situated 20 km to the north-east, is also presented. Important taxa found there include Van Dam's vanga Xenopirostris damii and Perrier's black sifaka Propithecus diadema perrieri. Both reserves are under threat, from burning, cattle-grazing and commercial forestry. Recommendations for increased protection include marking of reserve boundaries, increased wardening, and provision of local alternatives to forest timber and firewood. Development of tourism is seen as a way of providing these resources.

The palynology of a Holocene marginal peat swamp environment in Johore, Malaysia

The development of a shallow Holocene peat near Pekan Nanas, Johore, is studied pollen-analytically. A total of 47 pollen and spore types were determined. Three main ecological phases have been observed within the pollen profile. The profile starts on fluviatile, sandy sediments and shows a succession from an open swamp vegetation with mangrove influence to a marginal peat swamp facies with river bank vegetation. A radiocarbon dating on the deepest peat sample yielded an age of 4896 years ± 70 B.P.. This age corresponds remarkedly well with a general sea-level change recorded from West Malaysian shorelines at approximately 4800 years before present.

Ulv Aerial Applications of Naled For Control of A Complex of Livestock Insects on Platte River Pastures in Nebraska, 1975-76

Abstract Aerial applications of naled at various ULV rates were made over tree and shrub lined banks of the Platte River. Both times of season and volume of material applied were altered in an effort to obtain the most benefit in terms of application after most of the tabanids and mosquitoes had emerged and the best rate of application on river bank vegetation. Flights were made at temperatures above 80°F and when wind velocity was>10 MPH and at a 40 ft altitude. Insect counts were made with the use of bionculars and were made on one side of an animal only. Species identification was determined by net sweeping tame animals. Aedesvexans comprised 99% of the daytime mosquito population and the tabanid Tabanuslineola population was comprised of 91%, Chyrsopsdiscolis 5% and T.atratus 4%.

Changements récents de la Flore polonaise

In recent years, radical changes due to human interference have been observed in the flora of Poland. They consist of: (1) arrival and territorial extension of newcomers introduced by Man, and (2) disappearance of former components of the flora. Some 250–300 of the total of 2,250–2,300 species of vascular plants occurring in Poland have been introduced by Man and have become established in this country, about 100 of them being recent immigrants which have arrived during the sixteenth to twentieth centuries. They grow mostly in ‘ruderal’ places and in cultivated fields. Only 34 species of these newcomers have established themselves in the seminatural vegetation of river-banks, pastures, meadows, etc., and only 9 others have been able to penetrate into natural plant communities. Both native and formerly introduced components of the flora are dying out. It is difficult to estimate the total effect of this process; in some regions more than 10 per cent of the species of vascular plants that formerly occurred are supposed to have become extinct during the last 100 years. Indirect human influence through environmental changes is the main cause of this phenomenon. Direct changing of the whole vegetational cover is also very significant, whereas destruction of particular plant species seems to be of secondary importance.

The Merseyside Aquarium Society

ONE of the most extensive collections of British fresh-water aquaria and aquatic and river-side vegetation, in addition to foreign aquaria, has lately been brought together by the Merseyside Aquarium Society at its aquarium at Cliff House, Wallasey, which was opened by the Mayor of Wallasey in March 1932. The collection, which now comprises some sixty tanks, is claimed to be the most extensive of its kind in the North of England, and situated in extensive glass-houses, is largely the result of much hard work by enthusiasts in all classes of life in an effort to establish a really efficient scientific and public aquarium on Merseyside. The Merseyside Aquarium Society was instituted in 1926, largely through the efforts of Mr. F. Jefferies, a past president of the Liverpool Naturalists' Field Club, and incorporated in 1930, and its first president was the late Prof. James Johnstone. The president of the Society is Alderman A. H. Evans of Wallasey, the vice-presidents Prof. J. H. Orton, professor of zoology in the University of Liverpool, W. S. Laverock, lately of the Liverpool Museums, and Alderman D. R. Charlesworth, ex-mayor of Wallasey, and the honorary secretary, Mr. F. Jefferies. By a system of exchange, the Cliff Aquarium has acquired a number of valuable exhibits from the New York Aquarium Society, and it has lately been successful in breeding and rearing the axolotl (Amblystoma) to maturity. The present premises have been loaned the Society by the Wallasey Corporation, but the Aquarium is only considered a nucleus for a much larger building which it is hoped to have built as a municipal affair in the future. The Society issues a volume of Proceedings, holds six indoor meetings annually, and affords special help for the amateur aquarists, for the exchange of knowledge and experience amongst experts, and to promote school aquaria and vivaria.