scholarly journals Morphodynamic simulation of sediment deposition patterns on a recently stripped bedrock anastomosed channel

2018 ◽  
Vol 377 ◽  
pp. 51-56 ◽  
Author(s):  
David Milan ◽  
George Heritage ◽  
Neil Entwistle ◽  
Stephen Tooth
Keyword(s):  
National Park ◽  
Sediment Deposition ◽  
Low Flow ◽  
Field Observations ◽  
Deposition Patterns ◽  
High Magnitude ◽  
Vegetation Establishment ◽  
Olifants River ◽  
Flow Stage ◽  
Dryland Rivers

Abstract. Some mixed bedrock-alluvial dryland rivers are known to undergo cycles of alluvial building during low flow periods, punctuated by stripping events during rare high magnitude flows. We focus on the Olifants River, Kruger National Park, South Africa, and present 2-D morphodynamic simulations of hydraulics and sediment deposition patterns over an exposed bedrock anastomosed pavement. We examine the assumptions underlying a previous conceptual model, namely that sedimentation occurs preferentially on bedrock highs. Our modelling results and local field observations in fact show that sediment thicknesses are greater over bedrock lows, suggesting these are the key loci for deposition, barform initiation and island building. During peak flows, velocities in the topographic lows tend to be lower than in intermediate topographic areas. It is likely that intermediate topographic areas supply sediment to the topographic lows at this flow stage, which is then deposited in the lows on the falling limb of the hydrograph as velocities reduce. Subsequent vegetation establishment on deposits in the topographic lows is likely to play a key role in additional sedimentation and vegetation succession, both through increasing the cohesive strength of alluvial units and by capturing new sediments and propagules.

scholarly journals The influence of the 1991/92 drought on the woody vegetation of the Kruger National Park

Koedoe ◽  
1995 ◽  
Vol 38 (2) ◽  
Author(s):  
A.J. Viljoen
Keyword(s):  
National Park ◽  
Woody Species ◽  
Aerial Photographs ◽  
Woody Vegetation ◽  
General Area ◽  
Variable Intensity ◽  
The North ◽  
Olifants River ◽  
Area North ◽  
The Impact

All observations and data related to the impact of the 1991/92 drought on the woody vegetation, excluding the riverine vegetation of major rivers, are summarised. This includes data from a visual estimate of damage from aerial photographs, surveys on selected sites, and general observations. Despite lower rainfall, the area north of the Olifants River (excluding the far-northern part) was less affected than the area south of it, suggesting that the woody vegetation in the north is more adapted to drought. A characteristic of the drought was the localised distribution pattern and variable intensity of damage to the same species in the same general area. Information on 31 species are presented briefly. Although a large number of woody species was to some extent damaged, when the woody vegetation is considered as a whole, the influence of the drought was not very severe.

scholarly journals The implementation of an aquatic toxicity index as a water quality monitoring tool in the Olifants River (Kruger National Park)

Koedoe ◽  
1999 ◽  
Vol 42 (1) ◽  
Author(s):  
V. Wepener ◽  
J.H.J. Van Vuren ◽  
H.H. Du Preez
Keyword(s):  
Water Quality ◽  
Water Quality Index ◽  
National Park ◽  
Quality Index ◽  
Aquatic Toxicity ◽  
Temporal Trends ◽  
Kruger National Park ◽  
Toxicity Index ◽  
Olifants River

Large sets of water quality data can leave water quality managers and decision-makers totally overwhelmed. In order to convey the interpretation of the data in a simplified and understandable manner, the water quality results from bi-monthly surveys undertaken at seven different sampling sites in the Letaba, Olifants, and Selati rivers over a two year period (February 1990 to April 1992) were reduced to index values, using a water quality index. The water quality index (Aquatic Toxicity Index or ATI) revealed spatial and temporal trends. The higher index values, recorded for the sampling sites towards the eastern part of the Kruger National Park (KNP), revealed that the water quality was better than the quality measured in the Olifants River on the western bound-ary. The lowest index values were calculated for the Selati River, with index values consistently below 50. Index values indicate that the water quality in the Selati River was unsuitable for supporting normal physiological processes in fish. The water quality of the Selati River had an immediate impact on the water quality of the Olifants River directly below the confluence. Lower index values recorded at sites further downstream was also attributed to the influence of the Selati River since there are no known point sources of contaminants within the boundaries of the KNP. The index scores also elucidated temporal trends with lower scores evident during winter months. This was due to reduced flow in the Olifants River and a greater contribution of contaminated water from the Selati River. Index values increased following the first seasonal rains due to a dilution effect. Very low index values were recorded at certain sites during flood periods due to increased turbidity, reduced oxygen, and increased metal concentrations.

scholarly journals Research of a Spatial Flow of a Low-Flow Stage of a Svd-22 Centrifugal Compressor by Computational Fluid Dynamics Methods Using Super-Computer Technologies

2020 ◽  
Vol 220 ◽  
pp. 01082
Author(s):  
Yuri Kozhukhov ◽  
Serafima Tatchenkova ◽  
Sergey Kartashov ◽  
Vyacheslav Ivanov ◽  
Evgeniy Nikitin
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Centrifugal Compressor ◽  
Low Flow ◽  
Centrifugal Compressors ◽  
Control Measurement ◽  
Flow Features ◽  
Super Computer ◽  
Multistage Compressors ◽  
Flow Stage

This paper provides the results of the study of a spatial flow in a low-flow stage of a SVD-22 centrifugal compressor of computational fluid dynamics methods using the Ansys CFX 14.0 software package. Low flow stages are used as the last stages of multistage centrifugal compressors. Such multistage compressors are widely used in boosting compressor stations for natural gas, in chemical industries. The flow features in low-flow stages require independent research. This is due to the fact that the developed techniques for designing centrifugal compressor stages are created for medium-flow and high-flow stages and do not apply to low-flow stages. Generally at manufacturing new centrifugal compressors, it is impossible to make a control measurement of the parameters of the working process inside the flow path elements. Computational fluid dynamics methods are widely used to overcome this difficulties. However verification and validation of CFD methods are necessary for accurate modeling of the workflow. All calculations were conducted on one of the SPbPU clusters. Parameters of one cluster node: AMD Opteron 280 2 cores, 8GB RAM. The calculations were conducted using 4 nodes (HP MPI Distributed Parallel startup type) with their full load by parallelizing processes on each node.

scholarly journals Analisis Pengembangan Program Coorporate Social Responsibility (CSR) Pengelolaan Taman Nasional (PTN) Cianjur Taman Nasional Gunung Gede Pangrango

2017 ◽  
pp. 42
Author(s):  
Tun Susdiyanti
Keyword(s):  
Corporate Social Responsibility ◽  
Social Responsibility ◽  
Development Strategy ◽  
National Park ◽  
Swot Analysis ◽  
Descriptive Analysis ◽  
Field Observations ◽  
Evaluation Stage ◽  
Strategic Position ◽  
Corporate Social

This study aims to analyze the development of Corporate Social Responsibility (CSR) programs based on field observations and recommend appropriate strategies in implementing CSR in the National Park Management ( PTN ) Cianjur Gunung Gede Pangrango National Park. Working methods in this study include the evaluation stage uses a conceptual framework for descriptive analysis and recommendations on technical and drafting stage strategy using SWOT analysis. SWOT analysis, CSR program in Cianjur PTN is aggressive ( points 2.22; 1.74 ) is a strategic position. Proposed development strategy that can be implemented that increase the public's understanding, increase community participation, the optimization of the use of funds, and improve the performance extension, Polhut, PEH and operators in the implementation of CSR activities.

scholarly journals A note on the sex ratio of Steenbok Raphicerus Campestrts in the Kalahari Gemsbok National Park

Koedoe ◽  
1971 ◽  
Vol 14 (1) ◽  
Author(s):  
B. L. Penzhorn
Keyword(s):  
Sex Ratio ◽  
South African ◽  
National Park ◽  
Kruger National Park ◽  
Field Observations

Field observations on steenbok in the Kalahari Gemsbok National Park reveal a 1 : 1 sex ratio. This is corroborated by observations in the Kruger National Park and by a survey of steenbok material in two South African museums.

scholarly journals Natural history of Ctenus medius Keyserling, 1891 (Araneae, Ctenidae) I: observations on habitats and the development of chromatic patterns

2000 ◽  
Vol 60 (3) ◽  
pp. 503-509 ◽  
Author(s):  
C. E. ALMEIDA ◽  
E. F. RAMOS ◽  
E. GOUVÊA ◽  
M. do CARMO-SILVA ◽  
J. COSTA
Keyword(s):  
Life Cycle ◽  
Natural History ◽  
National Park ◽  
Common Species ◽  
Field Observations ◽  
Mata Atlântica ◽  
Adult Females ◽  
History Of ◽  
Males And Females ◽  
Phoneutria Nigriventer

Ctenus medius Keyserling, 1891 is a common species in several spots of Mata Atlântica, however there is a great lack of studies in all aspects of its natural history. This work aims to elucidate aspects of ecotope preference compared to large spiders, and to provide data on the development of chromatic patterns during its life cycle. The observations on the behavior of C. medius were done in the campus of Centro Universitário de Barra Mansa (UBM) by means of observations and nocturnal collections using cap lamps. For observations on the development of chromatic patterns, spiderlings raised in laboratory, hatched from an oviposition of a female from campus of UBM, and others spiderlings collected in field were used. The field observations indicate that: C. medius seems to prefer ecotopes characterized by dense shrub vegetation or herbal undergrowth; Lycosa erythrognatha and L. nordeskioldii seems to prefer open sites; Phoneutria nigriventer seems to prefer shrub vegetation and anthropogenic ecotopes as rubbish hills; Ancylometes sp. seems to prefer ecotopes near streams. Concerning chromatic patterns, it was observed that males and females show well distinct patterns during the last two instars, allowing distinction by sex without the use of a microscope. Through chromatic patterns it was also possible to draw a distinction between C. medius and C. ornatus longer that 3 mm cephalothorax width. 69 specimens of C. medius (males and females) collected in the campus of UBM did not show a striking polymorphism in chromatic pattern, but one among 7 adult females collected in National Park of Itatiaia, showed a distinct chromatic pattern.

scholarly journals The contemporary geomorphology of the Letaba River in the Kruger National Park

Koedoe ◽  
2001 ◽  
Vol 44 (1) ◽  
Author(s):  
B.P. Moon ◽  
G.L. Heritage
Keyword(s):  
South Africa ◽  
Flow Regime ◽  
Field Observation ◽  
National Park ◽  
Kruger National Park ◽  
The Other ◽  
Northern Province ◽  
Sediment Delivery ◽  
North East ◽  
Olifants River

The Letaba River drains part of Northern Province in north-east South Africa. Its catchment has been modified significantly by human activity which has affected the flow regime; it experiences only ephemeral flows through the Kruger National Park to its confluence with the Olifants River. Although the Letaba is similar to the other rivers in the Kruger National Park in that it displays some bedrock influenced channel features, increased sediment delivery from the degraded catchment upstream has resulted in extensive alluviation within the channel. Sections of channel flowing over bedrock with no sediment covering are rare, and the river comprises a series of channel types: mixed anastomosing, alluvial braided, mixed pool-rapid and alluvial single thread. Each is characterised by a different combination of morphological units which relate to the degree of alluviation in the channel. These channel types are described in detail and inferences are made concerning their formation and maintenance from field observation and measurement.

Redescription of Lamproglena Clariae Fryer, 1956 (Copepoda, Lernaeidae), With Notes On Its Occurrence and Distribution

Crustaceana ◽  
1996 ◽  
Vol 69 (4) ◽  
pp. 509-523 ◽  
Author(s):  
A. Avenant-Oldewage ◽  
Hazel M. Marx
Keyword(s):  
Electron Microscopy ◽  
South Africa ◽  
Scanning Electron Microscopy ◽  
National Park ◽  
Kruger National Park ◽  
Gill Parasite ◽  
Morphological Findings ◽  
Olifants River ◽  
First Time ◽  
Scanning Electron

AbstractThe morphology of the gill parasite Lamproglena clariae Fryer, 1956, from the Olifants River, Kruger National Park, South Africa, was studied with the aid of light and scanning electron microscopy. Ultrastructural details of all appendages are given as well as a table and map with information on the occurrence and distribution of L. clariae in Africa. Important morphological findings include: the observation of only one claw on the maxilla; first time findings and descriptions of the nuchal organ, upper and lower lips, the fifth pair of legs and circular openings on all appendages.

scholarly journals Pengembangan Ekowisata Batu Katak Melalui Metode Swot Analisis

2018 ◽  
Vol 1 (2) ◽  
pp. 231-237
Author(s):  
Yayuk Yuliana ◽  
Slamet Indarjo
Keyword(s):  
Natural Resource ◽  
Spatial Planning ◽  
National Park ◽  
Buffer Zone ◽  
Field Observations ◽  
Natural Conditions ◽  
Alternative Strategies

Pengembangan ekowisata merupakan salah satu upaya untuk menjaga kelestarian hutan sebagai sumberdaya alam hayati dan mensejahterakan masyarakat di sekitarnya.  Dusun Batu Katak merupakan salah satu dusun yang berada di daerah penyangga  Taman Nasional Gunung Leuser.  Sejak tahun 2013 masyarakat Dusun Batu Katak telah membuka Ekowisata Batu Katak.  Wisatawan  yang berkunjung ke Ekowisata Batu Katak terus mengalami peningkatan. Penelitian yang dilakukan bertujuan untuk mengetahui faktor-faktor dalam pengembangan Ekowisata Batu Katak.  Metode pengumpulan data dengan melakukan studi literatur, observasi lapangan, wawancara dengan masyarakat dan stakeholder.  Analisis data dengan menggunakan analisis SWOT untuk merumuskan alternatif-alternatif strategi.  Hasil penyusunan alternatif-alternatif strategi diketahui terdapat 11 alternatif strategi.  Perencanaan  Ekowisata masih tetap mempertahankan kondisi alami dengan penataan ruang,  sirkulasi ekowisata yang tetap menjamin kenyamanan pengunjung dan penduduk. Ecotourism development is one of the efforts to preserve the forest as a natural resource and prosper the surrounding community. Batu Katak Village is one of the buffer zone of Gunung Leuser National Park. Since 2013 the Batu Katak community has opened the Batu Katak Ecotourism. Tourists visiting the Batu Katak Ecotourism continue to increase recently. The research was aimed to determine the factors in the development of Ecotourism in Batu Katak. Data was done by collecting the literature studies, field observations, interviews with the community and stakeholders. Data was analyzed using SWOT to formulate alternative strategies. The results of the preparation of alternative strategies had 11 alternative strategies. Ecotourism planning still maintained the natural conditions with spatial planning, ecotourism circulation which still guarantees the comfort of visitors and residents.

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