scholarly journals Ecological Distribution of Cyclemys oldhamii (Gray, 1863) from Nepal

Our Nature ◽  
1970 ◽  
Vol 2 (1) ◽  
pp. 7-12 ◽  
Author(s):  
Kalu Ram Rai
Keyword(s):  
Habitat Loss ◽  
Paddy Field ◽  
Flood Plain ◽  
Southern Slope ◽  
Ecological Distribution ◽  
Eupatorium Adenophorum ◽  
Adult Specimen ◽  
Juvenile Specimen ◽  
River Valleys ◽  
Ecological Habitats

Tangting River originates from southern slope of Murtidanda of Mahabharat range and forms a very narrow v-shaped agriculturally fertile valley in lower parts of Chure hills. It has three main tributaries merging from east and west. Water is clear with rocky bed and margin is covered with thick bushes of semi-shrubs (Eupatorium adenophorum). During the herpetological survey, a live juvenile specimen of Cyclemys oldhamii (Gray, 1983) was collected from the periphery of Banmare Khola, an eastern tributory of the river. It was found hiding in the paddy field in the flood plain of Tangting river (280 m), and another adult specimen was collected from Dhobi Khola (450 m), a western tributory of the river. Empty shells were also collected from Garuwa and Mai valleys, respectively. Tangting and Garuwa river valleys are the favourable habitats for Cyclemys oldhamii. The main reason of discontinued distribution is habitat loss by deforestation. Key words: Cyclemys, Morphology, Ecological habitats, Distributiondoi:10.3126/on.v2i1.317Our Nature (2004) 2: 7-12

Showing the vegetation cover of flood-plains and river valleys on the Vegetation Map of Kazakhstan and middle Asia

1995 ◽  
pp. 58-66
Author(s):  
N. M. Kalibernova
Keyword(s):  
Plant Communities ◽  
Vegetation Cover ◽  
Flood Plain ◽  
Vegetation Map ◽  
Flood Plains ◽  
Additional Information ◽  
Ground Waters ◽  
The Matrix ◽  
River Valleys ◽  
Former Ussr

The fragment of the legend of the map concerning the vegetation of flood- plains and river-valleys in the subzones of northern and southern deserts is presented in the article. The map is compiled in Department of Vegetspon Geography and Cartography of Komarov Botanical Institute by a large team of botanists-geographers of the former USSR. The nature environments determining the development of vegetation of river-valleys in arid climate are conditioned by the intrazonal factors (alluvial and flood processes) at the background of natural zonal factors. Contrasts of environments and corresponding plant communities manifest themselves first of all. Mineralization of ground waters, salinity of soils, including the alluvial ones, are of essential importance. The practice of vegetation mapping of unstable habitats, to which floodplain landscapes belong, has shown that units of phytocoenological classification is of little use for this purpose. The heterogeneity of vegetation, consisting of short-term unstable serial communities generates a need for typification of space combinations of such phytocoenoses. For this purpose it is convenient to use generalized ecological-dinamic series, including plant communities of all levels within the limits of definite segment of valley. These series are the mapping units on the map. The vegetation of the first terrace is also nessecary to include in a single series with flood-plain vegetation because it has supplementary influence of ground waters. The higher divisions of the legend are based on zonal characters: vegetation of valleys in northern, middle and southern deserts. 13 numbers are used to show the vegetation cover of flood-plains and valleys. Additional 7 numbers are used for the out-of-valley meadow vegetation. The content is enriched by using of the letters by the numbers showing the geographic variants of series and ciphers for combination of series and out-of-series communities. The text legend is supplemented by the matrix (table), showing the subordination of subtitles, zonal position and geographic distribution of divisions. The types of series in the matrix are listed with indication of the main dominant species that gives the additional information on the legend divisions. The author's conclusion is that valley vegetation reveals clearly the zonal features, correlating with zonal (desert) vegetation.

scholarly journals Temporal and spatial variation of NPP and its response to climatic factors in main river valleys on the southern slope of Qilian Mountains

2019 ◽  
Vol 131 ◽  
pp. 01044
Author(s):  
Rong-rong Yang ◽  
Guang-chao Cao ◽  
Sheng-kui Cao ◽  
Yao Lan ◽  
Zhuo Zhang ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Climatic Factors ◽  
Growing Season ◽  
Qilian Mountains ◽  
River Valley ◽  
Distribution Characteristics ◽  
Southern Slope ◽  
Qilian Mountain ◽  
Main River ◽  
River Valleys

Based on the NPP products of MODIS data, the spatial and temporal distribution characteristics of grassland NPP and its response to climatic factors in the vegetation growing season of the main river valleys in the southern slope of Qilian Mountains from 2000 to 2016 were carried out by correlation analysis and spatial interpolation. The research further provides a scientific basis for the quality evaluation of grassland ecosystems on the southern slope of Qilian Mountain and the rational use of grassland resources along the river. The results show that: (1) With the increasing distance of buffers on both sides of the river, the NPP of grassland in each year shows the characteristics of “single-peak” distribution, which is increased first and then decreased; (2) the NPP of grassland in the main river valley of the southern slope of Qilian Mountain The spatial distribution characteristics show a trend of increasing from northwest to southeast. (3) The spatial distribution of NPP and air temperature in the main river valleys of the southern slope of Qilian Mountains is gradually increasing from northwest to southeast, but the spatial distribution correlation coefficient of NPP and precipitation in the river valley grassland of vegetation growing season basically shows a trendof decreasing from northwest to southeast.

The Geology of the Area

1987 ◽  
Vol 53 (s1) ◽  
pp. 4-4
Author(s):  
B W Conway
Keyword(s):  
Sea Level ◽  
Flood Plain ◽  
Last Interglacial ◽  
Average Width ◽  
Late Professor ◽  
Geological Maps ◽  
Geological Sciences ◽  
River Valleys ◽  
Thames River

Mr B W Conway of the Institute of Geological Sciences has kindly made the following comments on the geology of the site:“The causewayed enclosure is sited on the eroded terminal surface of the gravel train of the Upper Floor Plain Terrace at the junction of the Coinè and Thames river valleys (see OS 6 inch geological maps Buckinghamshire 56 SE, 58 NE and Middlesex 19 NE and SE (and Fig 2)). The late Professor Zeuner traced the profile of this terrace and claimed that it grades into the Late Monasirian sea level (7.5 metres) of the latter part of the last interglacial. The Coinè valley Flood Plain joins that of the Thames at Wraysbury and projects into the Thames as a distinct, slightly raised, delta. This delta was formed by the piling up of aggradation by the Coinè beyond the capacity of the Thames to remove it. The presence of this delta was the cause of the breaking up of the Coinè into a series of distributory channels: mainly those of the River Coinè, the Coinè Brook and Wyrardisbury River. These in turn eroded the Cclne delta and the Flood Plain gravel train. Erosion by the several distributory channels left slightly elevated gravel ridges between their valleys and clays, peats, and silts accumulated in these valleys. The eroded remnants of the delta and the Flood Plain Terrace appear as low “islands” of gravel between marshy stream valleys. The Staines causewayed enclosure is sited on the southern tip of the largest of these islands, which is approximately 4km long, has an average width of about 0.4km, and an area of approximately 182.lha.”

Complex geomorphological characteristics and relief geodynamic features of morphostructural units of the southern slope of the Greater Caucasus

2021 ◽  
Vol 07 (02) ◽  
pp. 61-63
Author(s):  
Qüdrət Tərlan oğlu Məmmədli ◽  
Keyword(s):  
Key Words ◽  
Geological Structure ◽  
Southern Slope ◽  
Greater Caucasus ◽  
River Valleys ◽  
Geomorphological Analysis

According to the modern geodynamic concept of lithosphere pans, the geological structure of the Greater Caucasus in the system of geosynclinal and platform regions is very complex. This situation, along with different conditions for the geomorphological development of the area, led to the formation of a complex and diverse relief with different ridges, massifs, inland basins, river valleys and other small morphostructures and morphosculptures. Key words: Greater Caucasus, southern part of Greater Caucasus, southern slopes, mosfostructure, geomorphological analysis, relief forms

Geographical separation of diploid and triploid cytotypes of Allium scorodoprasum in Lithuania

Biologia ◽  
2013 ◽  
Vol 68 (4) ◽  
Author(s):  
Birutė Karpavičienė
Keyword(s):  
Environmental Variables ◽  
Somatic Chromosome ◽  
Forest Edges ◽  
Ecological Distribution ◽  
Geographical Separation ◽  
Allium Scorodoprasum ◽  
High Level ◽  
Mesobromion Erecti ◽  
River Valleys ◽  
Somatic Chromosome Numbers

AbstractThe aim of this study was to determine the geographical and ecological distribution of Allium scorodoprasum cytotypes in Lithuania. 46 populations were studied: environmental variables were recorded and somatic chromosome numbers of 797 individuals from all populations were assessed. Diploids were found in 13 populations in the northern part of the study area, while triploids occurred in 33 populations from the western part of Lithuania. A. scorodoprasum frequently occurred in river valleys, particularly in the rarely flooded high level floodplains or on lower terraces. Only one population was recorded in Alno-Ulmion forest and three on the Glechometalia hederaceae forest edges, while 42 populations occurred in mesophilous or semidry Arrhenatheretalia elatioris, Mesobromion erecti and Trifolio-Geranietea sanguinei grasslands. No distinct differences in relative frequencies of diploid and triploid cytotypes in different plant communities were found whereas the soil chemical composition between the habitats of both cytotypes differed statistically. These differences however were indicative of the geographical separation of habitats rather than ecological differentiation between the two cytotypes. The results suggest that there were at least two separate roads of colonization of diploid and triploid A. scorodoprasum into Lithuania.

scholarly journals Habitat use by the globally endangered Hinde's Babbler Turdoides hindei and its sympatric relative, the Northern Pied Babbler T. hypoleucus

1998 ◽  
Vol 8 (1) ◽  
pp. 59-65 ◽  
Author(s):  
Peter Njoroge ◽  
Leon A. Bennun ◽  
Luc Lens
Keyword(s):  
Endangered Species ◽  
Habitat Use ◽  
Group Size ◽  
Habitat Loss ◽  
Conservation Status ◽  
Habitat Type ◽  
River Valleys ◽  
Feeding Grounds ◽  
Foraging Ranges ◽  
Central Kenya

SummaryWe examined and compared territoriality and habitat use of two congeneric babbler species in Kirinyaga district, central Kenya, with the aim of explaining their differences in global conservation status. Hinde's Babbler Turdoides hindei is a scarce, globally Endangered species whereas Northern Pied Babbler T. hypoleucus is much more abundant and widespread, and occurs throughout the range of Hinde's Babbler. Our findings suggested a lack of flexibility in the choice of habitat by Hinde's Babbler, whose territories were centred on a scarce habitat type: Lantana thickets in river valleys or near swamps. The two species showed similar daily foraging ranges but Hinde's Babbler occupied smaller group territories, whose size was not related to group size. Aggressive encounters between the two species occurred over shared feeding grounds, all of which were initiated and won by Hinde's Babbler. Its dependence on Lantana thickets makes Hinde's Babbler highly susceptible to further habitat loss within its range.

Floodplain Infrastructure and the Toxic Tide

2015 ◽  
pp. 150-173
Author(s):  
Sanford R. Bender
Keyword(s):  
Climate Change ◽  
Invasive Species ◽  
Sea Level Rise ◽  
Sea Level ◽  
Habitat Loss ◽  
Flood Plain ◽  
Storm Events ◽  
Global Issues ◽  
Environmentally Sensitive ◽  
Coastal Sand

The human species is drawn to water. They are attracted by its dynamic flow and the promise of renewal that can lift their spirits up from the mundane. However, there is a growing awareness of how prior and current building practices continue to jeopardize environmentally sensitive wetlands, estuaries, bays, rivers, and coastal sand barriers. Constructing infrastructure in the floodplain causes erosion, pollution, habitat loss, invasive species, and increased vulnerability to hurricanes and other flooding disasters. This chapter will focus primarily on how building infrastructure located in the flood plain can affect the environment under the duress of catastrophic storm events. Reference is made to more far reaching phenomena global issues such as climate change, sea level rise, shifting continental fault lines, and other meteorological and geological changes that appear to be hastening the appearance of major disastrous events.

Landscape Change and the Cultural Evolution of the Hohokam along the Middle Gila River and Other River Valleys in South-Central Arizona

2001 ◽  
Vol 66 (2) ◽  
pp. 285-299 ◽  
Author(s):  
Michael R. Waters ◽  
John C. Ravesloot
Keyword(s):  
Flood Plain ◽  
Late Nineteenth Century ◽  
San Pedro River ◽  
Gila River ◽  
South Central ◽  
Channel Erosion ◽  
Major Period ◽  
Sphere Of Influence ◽  
Political Economic ◽  
River Valleys

Changes in river floodplain morphology can have devastating consequences for irrigation agriculturalists. Channel erosion occurred in the late nineteenth century, on the flood plain of the middle Gila River, Arizona and severely impacted the native Akimel O' odham (Pima) farmers. Prior to the Akimel O' odham, the prehistoric Hohokam also pursued irrigation agriculture along this river. Geoarchaeological investigations of the Gila River flood plain document a major period of channel cutting and widening sometime between A.D. 1020 to 1160. This channel erosion is coincident with the partial abandonment of large Hohokam villages and significant population rearrangements. It also marks the beginning of a major social reorganization when ball-courts were replaced by platform mounds as the social integrative structure and the Hohokam sphere of influence contracted. Other rivers utilized by the Hohokam—the Santa Cruz River, San Pedro River, and Tonto Creek-also experienced channel cutting between A.D. 1050 and 1150. Thus, a regional episode of channel erosion appears to have been a major factor that contributed to the reorganization seen in the Hohokam archaeological record. These synchronous landscape changes would have severely impacted Hohokam irrigation systems and food production capabilities. This undoubtedly created stresses within Hohokam society which in turn may have accelerated social, political, economic, ideological, and demographic changes that were already underway.

scholarly journals Ecological constraints associated with genome size across salamander lineages

2019 ◽  
Vol 286 (1911) ◽  
pp. 20191780 ◽  
Author(s):  
Gavia Lertzman-Lepofsky ◽  
Arne Ø. Mooers ◽  
Dan A. Greenberg
Keyword(s):  
Genome Size ◽  
Life History Traits ◽  
Larval Habitat ◽  
Evolutionary Constraint ◽  
Evolutionary Transition ◽  
Ecological Distribution ◽  
Ecological Constraints ◽  
Larval Habitats ◽  
Taxonomic Groups ◽  
Ecological Habitats

Salamanders have some of the largest, and most variable, genome sizes among the vertebrates. Larger genomes have been associated with larger cell sizes, lower metabolic rates, and longer embryonic and larval durations in many different taxonomic groups. These life-history traits are often important for dictating fitness under different environmental conditions, suggesting that a species' genome size may have the potential to constrain its ecological distribution. We test how genome size varies with the ephemerality of larval habitat across the salamanders, predicting that species with larger genomes will be constrained to more permanent habitats that permit slower development, while species with smaller genomes will be more broadly distributed across the gradient of habitat ephemerality. We found that salamanders with larger genomes are almost exclusively associated with permanent aquatic habitats. In addition, the evolutionary transition rate between permanent and ephemeral larval habitats is much higher in salamander lineages with smaller genome sizes. These patterns suggest that genome size may act as an evolutionary constraint on the ecological habitats of salamanders, restricting those species with large genomes and slower development to habitats with permanent sources of water.

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