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Quantitative description of woody plant communities: Part I. An approach
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: G.N. Smit --- Department of Agriculture and Water Supply (Transvaal Region), Republic of South AfricaVarious descriptive units for woody plant communities are proposed. These are the Evapotranspiration Tree Equivalent (ETTE), Browse Tree Equivalent (BTE) and Canopied Subhabitat Index (CSI), which describe the status of a woody community in terms of potential moisture use, value... -
Quantitative description of woody plant communities: Part II. Computerized calculation procedures
Item type: Journal Article • Journal: Journal of the Grassland Society of Southern Africa • Authors: G.N. Smit --- Department of Agriculture and Water Supply (Transvaal Region), Republic of South AfricaCalculation procedures for various quantitative descriptive unit‐values are described. These procedures are divided into primary and secondary calculations. The former is then divided into the calculation of spatial tree volume and preliminary calculations regarding the complete quantitative description. The latter... -
Use of the SDSS test to predict the protein content and bread volume of wheat cultivars
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: O.T. de Villiers --- Department of Botany, Republic of South Africa E.W. Laubscher --- Centre for Cereal Research, Department of Agronomy and Pastures, Republic of South AfricaThe relationship between the sodium dodecyl sulphate sedimentation volume (SDSS test) and the protein content and bread volume of wheat cultivars was determined to ascertain whether the SDSS test could be used to predict these parameters of baking quality. This... -
A comparison of three methods of soil water content determination
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: K.M. Little --- , Republic of South Africa B. Metelerkamp --- , New Zealand C.W. Smith --- , Republic of South AfricaIn forestry the need to manage plantations on a sustainable site-specific basis requires the understanding and management of any growth limiting factors. Soil water regime is a factor considered to be of prime importance with respect to explaining differences in... -
Artificial neural networks and non-linear regression for quantifying the wood volume in Eucalyptus species
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Tays Silva Batista --- , Brazil Larissa Pereira Ribeiro Teodoro --- , Brazil Gileno Brito de Azevedo --- , Brazil Glauce Taís de Oliveira Sousa Azevedo --- , Brazil Nerison Luis Poersch --- , Brazil Marcus Vinicius Vieira Borges --- , Brazil Paulo Eduardo Teodoro --- , BrazilWood volume is the variable that best represents the yield of planted forests, and several regression models are used in its estimation. Artificial neural networks (ANNs) are recognised for their accuracy and generalisation capacity associated with the quality and quantity... -
RATE OF EROSION IN THE CATCHMENT OF THE BULBERGFONTEIN DAM NEAR REDDERSBURG IN THE ORANGE FREE STATE
Item type: Journal Article • Journal: Journal of the Limnological Society of Southern Africa • Authors: J.S. Ie Roux --- Department of Geography, South Africa Z.N. Roos --- Department of Geography, South AfricaThe volume of sediment in the Bulbergfontein Dam was computed after mapping the area of the dam and ascertaining the depth of the sediment by digging and augering. The watershed of the impoundment had been delimited by means of aerial... -
PHYSICAL, CHEMICAL AND BIOTIC RESPONSES TO DECREASING WATER DEPTH IN A HIGHVELD PAN FOLLOWING WET AND DRY SUMMERS
Item type: Journal Article • Journal: Southern African Journal of Aquatic Sciences • Authors: KH Rogers --- Department of Botany, WN Ellery --- Department of Botany, NL Winternitz --- Department of Botany, R Dohmeier --- Department of Botany,The classification of highveld pans by Geldenhuys (1982) emphasized the spatial diversity of morphology, vegetation and fauna. However, since the characteristics of individual pans also change seasonally and over longer term wet/dry cycles, he called for more detailed limnological studies... -
A novel method for estimating tree dimensions and calculating canopy volume using digital photography
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: AS Barrett --- Applied Behavioural Ecology and Ecosystems Research Unit, South Africa LR Brown --- Applied Behavioural Ecology and Ecosystems Research Unit, South AfricaStudies on plant phenology and browse capacity require effective methods to rapidly quantify plant dimensions such as tree height, height of maximum canopy diameter, height of first leaves, maximum canopy diameter, and diameter of trunk(s) at height of first leaves... -
Savanna browse production. 1: Determinants and measurement
Item type: Journal Article • Journal: African Journal of Range & Forage Science • Authors: Caryn A Penderis --- School of Life Sciences, South Africa Kevin P Kirkman --- Grassland Science, South AfricaWith the rapid expansion of wildlife ranching and conservation in South African savannas and the resultant increase in multi-species grazing and browsing systems, information on browse production potential is essential for determination of carrying capacity. This study, conducted on three... -
Analysis of individual tree volume equations for Cupressus lusitanica in Munessa forest, Ethiopia
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: T. TeshomeThree different volume equations were fitted to individual tree volume (V) data collected on 260 Cupressus lusitanica trees from 49 plantations in Munessa Shashemene Forest, Ethiopia. The data were first split randomly into equation development and equation testing data sets... -
Root volume and raising period affect field performance of Pinus patula cuttings in South Africa
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: R. G. Mitchell J. Zwolinski N. B. Jones A. D. BayleyThe propagation of pines through cuttings has become a commercial means of rapidly multiplying improved genetic material for operational use in forestry companies. Cuttings of pines are produced entirely in containers in South Africa. Containers, however, can negatively affect plant... -
Predicting fir trees stem diameters using Artificial Neural Network models
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: MariaJ. DiamantopoulouThe financial exploitation of forests constitutes an important part of human activity. This effort is being made in order to conserve the sustainable exploitation while avoiding the degradation of the environment. One of the most important operations in forest mensuration... -
Modeling woody vegetation resources using Landsat TM imagery in northern Namibia
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: Alex Verlinden Risto LaamanenIn 1995 a forest inventory covering northern Namibia was initiated, based on stratified systematic field sampling of plots with a radius of up to 30 m. In these plots detailed tree parameters were measured. Due to security problems the most... -
A root-bound index for evaluating planting stock quality of container-grown pines
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: D.B. South R. G. MitchellPot-binding can adversely affect the performance of container-grown stock. One factor that affects pot-binding is the size of the root system in relation to the size of the container. The aim of this study was to determine if an objective... -
Alternative Taper Curve Estimation Methods for Eucalyptus cloeziana (F. Muell.)
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: K. P.A. Eerikäinen --- Faculty of Forestry, Finland D. Mabvurira --- , Zimbabwe J. Saramäki --- ,Three types of taper estimation methods for Eucalyptus cloeziana were applied and compared by using Zambian and Zimbabwean plantation data. The methods are: (1) Schumacher's taper equation, (2) diameter prediction method and (3) polynomial taper curve. The Schumacher's taper equation... -
Update on the bathymetry of Lake Mweru (Zambia), with notes on water level fluctuations
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: ArthurR Bos CyprianK Kapasa PaulAM van ZwietenA new bathymetric map of Lake Mweru was developed, displaying previously unknown morphological features and correcting the shape of the shoreline as presented in older maps. Water depth was measured during 11 transect cruises in early 1994. Two depressions were... -
Volume Regression Equations for Eucalyptus Grandis on the Coastal Plain of Zululand
Item type: Journal Article • Journal: South African Forestry Journal • Authors: B.V. Bredenkamp --- Natal Forestry Research Centre,Separate volume regression equations for pulpwood, sawtimber and over-mature Eucalyptus grandis are presented. An investigation of Schumacher and Hall's volume equation indicated that a better fit may be obtained by adding a constant to the dbh as predictor variable. The... -
The November 2011 irruption of buoy barnacles Dosima fascicularis in the Western Cape, South Africa
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: PG Ryan --- Percy FitzPatrick Institute of African Ornithology, DST/NRF Centre of Excellence, South Africa GM Branch --- Marine Research Institute, Department of Zoology, South AfricaNovember 2011 saw an unprecedented irruption of buoy barnacles Dosima fascicularis in coastal waters off the Western Cape, South Africa. Buoy barnacles not uncommonly strand in the region attached to feathers, plastic litter and other small objects, but the 2011... -
Stand biomass and volume estimation for Miombo woodlands at Kitulangalo, Morogoro, Tanzania
Item type: Journal Article • Journal: The Southern African Forestry Journal • Authors: S.A.O. Chamshama --- Faculty of Forestry and Nature Conservation, Tanzania A.G. Mugasha --- Faculty of Forestry and Nature Conservation, Tanzania E. Zahabu --- Faculty of Forestry and Nature Conservation, TanzaniaTree volume and biomass equations developed for Kitulangalo area in Morogoro, Tanzania ignored small branches and small trees. Consequently, this study was carried out to develop new individual tree volume and biomass equations, and assess current regeneration status, biodiversity and... -
Determining the effect of tree size, bark-wood bond strength and tree form on the productivity of an excavator-based harvester in Acacia mearnsii in the KwaZulu-Natal forestry region of South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: M Ramantswana --- , South Africa A McEwan --- , South Africa J Pauw --- , South AfricaThe aim of this study was to determine the effect of tree size, bark-wood bond strength and tree form on the productivity of cut-to-length harvesting of Acacia mearnsii, using an excavator-based harvester with a SP Maskiner harvester head in the... -
Machine productivity and residual harvesting residues associated with a cut-to-length harvest system in southern Tasmania
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: MR Ghaffariyan --- , Australia J Sessions --- Department of Forest Engineering, Resources and Management, USA M Brown --- Office of PVC Research, AustraliaThe cut-to-length method is a preferred method for harvest of pine plantations in Australia. The cut-to-length method studied in southern Tasmania consists of a feller-buncher, processor, forwarder, grapple loader and tractortrailers that were producing only pulp logs for the plantation... -
Development and validation of stem volume models for Pinus kesiya in Benguet province, Philippines
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Roscinto IanC Lumbres --- Department of Forest Resources, Korea Young Jin Lee --- Department of Forest Resources, KoreaStem volume equations (overbark) were developed, using established volume equation forms, and validated using a subset of the data collected for Pinus kesiya in Benguet province, Philippines. A total of 481 trees from Pinus kesiya stands in Benguet were measured... -
A comparison between excavator-based harvester productivity in coppiced and planted Eucalyptus grandis compartments in KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Muedanyi Ramantswana --- Nelson Mandela Metropolitan University, South Africa Andrew McEwan --- Nelson Mandela Metropolitan University, South Africa Jaap Steenkamp --- Nelson Mandela Metropolitan University, South AfricaDue to the labour challenges in South Africa, mechanised forestry equipment has increasingly been required to operate in complex forest conditions – such as coppiced Eucalyptus compartments – where they have not operated before. For this reason, harvesters are either... -
Performance of Eucalyptus dunnii as influenced by vegetation control when felled at nine years in KwaZulu-Natal, South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: KM LittleIn 1997, a trial was initiated to determine the impact of eight vegetation control treatments on the growth of Eucalyptus dunnii Maiden at a warm-temperate site in the KwaZulu-Natal Midlands, South Africa. The treatments included a Weedy and Weed-free check,... -
The effect of positive end-expiratory pressure on pulse pressure variation
Item type: Journal Article • Journal: Southern African Journal of Anaesthesia and Analgesia • Authors: FJ Smith --- Department of Anaesthesiology, School of Medicine, Faculty of Health Sciences, M Geyser --- Department of Anaesthesiology, School of Medicine, Faculty of Health Sciences, I Schreuder --- Department of Anaesthesiology, School of Medicine, Faculty of Health Sciences, PJ Becker --- Biostatics Unit,Objectives: To determine the effect of different levels of positive end-expiratory pressure (PEEP) on pulse pressure variation (PPV). -
Estimating wood volume from canopy area in deciduous woodlands of Zimbabwe
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Tawanda W Gara --- Department of Geography and Environmental Science, Zimbabwe Amon Murwira --- Department of Geography and Environmental Science, Zimbabwe Emmerson Chivhenge --- Department of Geography and Environmental Science, Zimbabwe Timothy Dube --- Discipline of Geography, School of Agricultural, Earth and Environmental Sciences, South Africa Tsitsi Bangira --- SAEON Egagasini Node, South AfricaIn this study we tested the predictive ability of canopy area in estimating wood volume in deciduous woodlands of Zimbabwe. The study was carried out in four sites of different climatic conditions. We used regression analysis to statistically quantify the... -
Assessing the utility of ALOS PALSAR and SPOT 4 to predict timber volumes in even-aged Eucalyptus plantations located in Zululand, South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Riyad Ismail --- Sappi Forests, South Africa Horst Kassier --- Sappi Forests, South Africa Morries Chauke --- Sappi Forests, South Africa Francesco Holecz --- Sarmap SA, Switzerland Nico Hattingh --- Sappi Forests, South AfricaIn commercial forestry, regular terrestrial enumerations of the growing stock are required for the valuation, sustain-able management and planning of current and future timber supplies. In this study we examined whether the combination of synthetic aperture radar (ALOS PALSAR) and... -
A comparison of planting and coppice regeneration of Eucalyptus grandis × Eucalyptus urophylla clones in South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Jacob W Crous --- Sappi Forests, South Africa Louisa Burger --- Department of Forest and Wood Science, South AfricaResults from two coppice compared to replant trials are presented that originated from clone by site interaction (CSI) trials established on high‑ and low‑productivity sites in subtropical coastal KwaZulu‑Natal, South Africa. After the 84‑month CSI trial measurements were completed the... -
The implication of using a fixed form factor in areas under different rainfall and soil conditions for Pinus kesiya in Zambia
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Darius Phiri --- School of Natural Resources, Zambia Eliud Phiri --- 47 Second Street, Mindolo, Zambia Robby Kasubika --- School of Natural Resources, Zambia Donald Zulu --- School of Natural Resources, Zambia Chisala Lwali --- School of Natural Resources, ZambiaThe study was undertaken to evaluate form factors for Pinus kesiya growing in the three Zambia Forest and Forestry Industries Corporation (ZAFFICO) plantations – the Ndola, Ichimpe and Chati groups – under different rainfall (900–1 500 mm) and soil conditions (pH... -
Total tree, merchantable stem and branch volume models for miombo woodlands of Malawi
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Daud J Kachamba --- Department of Ecology and Natural Resource Management, Norway Tron Eid --- Department of Ecology and Natural Resource Management, NorwayThe objective of this study was to develop general (multispecies) models for prediction of total tree, merchantable stem and branch volume including options with diameter at breast height (dbh) only, and with both dbh and total tree height (ht), as... -
A taper function for Pseudotsuga menziesii plantations in Spain
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Carlos A López-Sánchez --- Instituto de Silvicultura e Industria de la Madera, México Roque Rodríguez-Soalleiro --- Departamento de Producción Vegetal, Spain Fernando Castedo-Dorado --- Departamento de Ingeniería y Ciencias Agrarias, Spain Sacramento Corral-Rivas --- División de Estudios de Posgrado e Investigación, México Juan G Álvarez-González --- Departamento de Ingeniería Agroforestal, SpainFive stem taper models belonging to three different taper function categories were fitted to data corresponding to 282 Pseudotsuga menziesii trees. The trees were selected in the area surrounding 61 research plots installed in Galicia, Asturias and the Basque Country,... -
Relationship between clutch size, egg volume and hatching success in a Yellow-legged Gull Larus michahellis colony in south-eastern Tunisia
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Abdessalem Hammouda --- Département des Sciences de la Vie, Tunisia Foued Hamza --- Département des Sciences de la Vie, Tunisia Jessica Pearce-Duvet --- Centre d'Ecologie Fonctionnelle et Evolutive (CEFE), France Slaheddine Selmi --- Département des Sciences de la Vie, TunisiaThis study aimed to test the hypothesis that clutch size covaries with egg volume and hatching success in the Yellow-legged Gull Larus michahellis. We determined clutch size and egg volume in a sample of 131 nests, and we used the... -
Indirect methods of tree biomass estimation and their uncertainties
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Marco A Njana --- Tanzania Forest Services Agency, TanzaniaTree aboveground biomass (AGB) may be determined using direct (weighing or biomass models) and indirect (involving the use of a form factor [FF]) or volume models, basic density [BD] and biomass expansion factor [BEF]) methods. Focusing on three dominant mangrove... -
Season, sex and age variation in the haematology and body condition of geometric tortoises Psammobates geometricus
Item type: Journal Article • Journal: African Zoology • Authors: Margaretha D Hofmeyr --- Chelonian Biodiversity and Conservation – Southern Africa, Biodiversity and Conservation Biology Department, South Africa Brian T Henen --- Chelonian Biodiversity and Conservation – Southern Africa, Biodiversity and Conservation Biology Department, South Africa Shasheen Walton --- Chelonian Biodiversity and Conservation – Southern Africa, Biodiversity and Conservation Biology Department, South AfricaBody condition and haematological indices provide powerful information when assessing wildlife health. Reference intervals for these indices can facilitate wildlife management, and would benefit initiatives to save the Critically Endangered geometric tortoise (Psammobates geometricus). We collected data from 126 geometric... -
Bark thickness and bark volume of Pinus patula in South Africa
Item type: Journal Article • Journal: Southern Hemisphere Forestry Journal • Authors: A. van LaarIn South Africa, tree volume tables and volume functions are usually based on the under bark stem volume. Many forest management studies, however, give the estimated over bark volume, in which case equations are required that estimate bark volume and... -
Estimation of taper rates and volume of smaller-sized logs in spotted gum saw timber plantations in Southeast Queensland, Australia
Item type: Journal Article • Journal: Southern Hemisphere Forestry Journal • Authors: TN Maraseni G Cockfield A ApanSpotted gum (Corymbia citriodora subsp. variegata) is a popular tree species for hardwood saw timber plantations in Southeast Queensland (SEQ), Australia. In many parts of the world, logs up to 10cm top diameter are considered to be merchantable logs and... -
Generating optimum solar output energy with three-dimensional photovoltaic system – the effect of solar radiation
Item type: Journal Article • Journal: African Journal of Science, Technology, Innovation and Development • Authors: Olufunmilayo Alice Mafimidiwo --- School of Engineering, South Africa Akshay Kumar Saha --- School of Engineering, South AfricaIn order to optimize the solar energy generated from a photovoltaic solar panel, adequate utilization of the global irradiation incident on the photovoltaic panel is necessary. Solar irradiation received on the surface of any material on the earth could be... -
The ‘suitcase hypothesis’: Can entrainment of meroplankton by eddies provide a pathway for gene flow between Madagascar and KwaZulu-Natal, South Africa?
Item type: Journal Article • Journal: African Journal of Marine Science • Authors: S Ockhuis --- Cape Peninsula University of Technology, South Africa JA Huggett --- Branch: Oceans and Coasts, Department of Environmental Affairs, South Africa G Gouws --- African Coelacanth Ecosystem Programme (ACEP), South Africa C Sparks --- Cape Peninsula University of Technology, South AfricaSimilarities in the marine fauna found off the coasts of southern Madagascar and KwaZulu-Natal Province (KZN), South Africa, led to the development of the ‘suitcase project,’ with the aim of establishing whether eddies that form off southern Madagascar may package... -
A first-approximation simple dynamic growth model for forest teak plantations in Gujarat state of India
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Vindhya Prasad Tewari --- Himalayan Forest Research Institute, India Bilas Singh --- Arid Forest Research Institute, IndiaTectona grandis (teak) is one of the most important tropical timber species occurring naturally in India. In India, teak is the single most important commercial timber species. Scientifically sound growth models, based on advanced modelling techniques, are often not available,... -
Rotation-end financial performance of vegetation control on Eucalyptus smithii in South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Keith M Little --- School of Natural Resource Management, South Africa Anssi Ahtikoski --- Natural Resources Institute Finland, Finland Andrew R Morris --- Institute for Commercial Forestry Research, South AfricaControl of competing vegetation during eucalypt regeneration is important but the cost-benefit of varying levels of control is not well understood. A trial was initiated to quantify the impact of five vegetation control treatments on Eucalyptus smithii R.T.Baker. to determine... -
Development of a stand density management diagram for Santalum album plantations in Karnataka, India
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Vindhya Prasad Tewari --- Himalayan Forest Research Institute, India Baragur N Diwakara --- Forest Biometry Division, Institute of Wood Science and Technology, IndiaStand density management diagrams are average stand-level models that graphically display the relationship between stand yield, density, height and diameter throughout the various stages of forest development in even-aged stands. These are useful tools for designing, displaying and evaluating alternative... -
A retrospective analysis of the effect of planning tumour volume on survival in cervical carcinoma
Item type: Journal Article • Journal: Southern African Journal of Gynaecological Oncology • Authors: Ilze Fourie --- Division of Radiation Oncology, Stellenbosch University, Tygerberg Academic Hospital, South Africa Hannah M Simonds --- Division of Radiation Oncology, Stellenbosch University, Tygerberg Academic Hospital, South AfricaIntroduction: Locally advanced stages of invasive cervical cancer (ICC) are associated with poor outcomes; factors influencing survival include increased tumour volume. In resource-constrained settings access to diagnostic imaging with CT and MRI is limited. Alternative methods of establishing tumour volume... -
Development and validation of a stem volume equation for Cupressus lusitanica in Gergeda Forest, Ethiopia
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Mengesha Tsega --- College of Environmental Science and Engineering, China Awoke Guadie --- Department of Biology, College of Natural Sciences, Ethiopia Zebene Lakew Teffera --- College of Environmental Science and Engineering, China Yigez Belayneh --- College of Environmental Science and Engineering, China Dongjie Niu --- State Key Laboratory of Pollution Control and Resource Reuse, ChinaStem volume equations were fitted for Cupressus lusitanica in Gergeda Forest, Ethiopia using six different established equation forms. A total of 260 trees were measured for their diameter at breast height (D), total height (H )and stem volume using destructive sampling... -
Characterisation of the soil pore system in relation to its hydraulic functions in two South African aeolian soil groups
Item type: Journal Article • Journal: South African Journal of Plant and Soil • Authors: Achamyeleh G Mengistu --- Department of Soil, Crop and Climate Sciences, South Africa Sabelo SW Mavimbela --- Department of Soil, Crop and Climate Sciences, South Africa Leon D van Rensburg --- Department of Soil, Crop and Climate Sciences, South AfricaThe characterisation of soil pores has a prime importance in soil hydrology particularly for soil water management in both irrigated and dryland agriculture. Hence, this study describes the soil pore system in the Clovelly and Hutton soil forms and its... -
A new sentiment index for the Islamic stock market
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Muhammad Asif Khan --- Faculty of Business and Accountancy, Malaysia Rubi Ahmad --- Faculty of Business and Accountancy, Malaysia Anna Azmi --- Faculty of Business and Accountancy, Malaysia Muhammad Akbar --- Birmingham City Business School, UKThis study attempts to examine the predictability of Google search volume (GSV) and to construct an appropriate investor sentiment index for Islamic stock markets for seven United States (US) Islamic stock indices. Using principal component analysis, we construct an appropriate... -
Diet of catfish Clarias buthupogon Sauvage, 1879 (Clariidae) in two rivers in the Yoko Reserve, Tshopo Province, Democratic Republic of the Congo
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: RB Mahamba --- Department of Phytotechnics, Democratic Republic of the Congo JN Ndjaki --- Department of Hydrobiology, Democratic Republic of the Congo AB Kankonda --- Department of Hydrobiology, Democratic Republic of the Congo J-C Micha --- Environmental Biology Research Unit (URBE), BelgiumThe diet of the catfish, Clarias buthupogon, was studied in two forest rivers in the Yoko Reserve, the Yoko and Biaro Rivers, from September 2008 to August 2009. Gill nets, long lines and traditional traps were used to catch the... -
Volume recovery and estimation of commercial volumes of Okan (Cylicodiscus gabunensis Harms) in southern Cameroon
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Julien M Seka --- Ministry of Forestry and Wildlife, National Forestry School, Cameroon Jean Bégin --- Department of Wood and Forest Sciences, Faculty of Forestry, Geography and Geomatics, CanadaThe objective of this study was to quantify the volume of residues and develop volume equations for estimation of commercial outside-bark volumes of Okan (Cylicodiscus gabunensis) at different logging stages. Two hundred and five stems with diameter at breast height... -
Stem volume and tree biomass harvested by different thinning intensities from dense and sparse karee stands in Central Bushveld, South Africa
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Kassahun T Maru --- Department of General Forestry, Wondo Genet College of Forestry and Natural Resources, Ethiopia Coert J Geldenhuys --- Department of Plant and Soil Sciences, South Africa Paxie W Chirwa --- SAFCOL Forest Chair for Forest Postgraduate Programme, Department of Plant and Soil Sciences, South AfricaThe aim of this study was to determine the aboveground stem volume and tree biomass of the multi-stemmed karee tree (Searsia lancea) for its potential use for producing wood chips and/or pellets. A stratified random sampling was done, by selecting... -
Height and volume functions for Pinus lawsonii, Pinus leiophylla, Pinus oocarpa and Pinus pringlei plantations in Guarei, São Paulo, Brazil
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Rafaella Carvalho Mayrinck --- School of Environment and Sustainability, Canada Vinicius Gontijo Rodrigues Roque --- Grupo Resinas Brasil, Complexo Florestal Sao Pedro, Brazil Antonio Carlos Ferraz Filho --- Departamento de Engenharia, Brazil Eduardo Michaloski Filho --- Grupo Resinas Brasil, Complexo Florestal Sao Pedro, Brazil Fredo Arias-King --- T & R Chemicals, USA Andressa Ribeiro --- Departamento de Engenharia, BrazilInventories are time- and money-consuming. Hence, accurate equations to estimate difficult-to-measure variables are desirable, especially for species that are not commercially established, such as Pinus lawsonii, P. leiophylla, P. pringlei and P. oocarpa. This study aimed to fit height and... -
Improving the forecasts of commercial timber volume in transition forest in the northern Brazilian Amazon
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Robson B de Lima --- , Brazil Rinaldo LC Ferreira --- , Brazil José AA da Silva --- , Brazil Marcelino C Guedes --- , Brazil Jadson C de Abreu --- , Brazil Cinthia P de Oliveira --- , Brazil Robson C Lima --- , Brazil Diego AS da Silva --- , Brazil Renan M Santos --- , Brazil Erik PF Carvalho --- , Brazil Robson M de Araújo Silva --- , BrazilThe commercial volume in tropical forests is fundamental to the implementation of sustainable forest management plans. However, in the absence of local or generic volumetric equations, most forest managers and forest services are still using traditional form factors (FF) to... -
Development and testing of volume models for Pinus nigra Arn., Fagus sylvatica L., and Quercus pubescens Willd.
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Dimitrios I Raptis --- , Greece Vassiliki Kazana --- , Greece Angelos Kazaklis --- , Greece Christos Stamatiou --- , GreeceVolume models were developed and tested for Pinus nigra Arn., Fagus sylvatica L., and Quercus pubescens Willd. to accurately predict the woody stem volume at tree level, since despite the economic importance of these species in the Mediterranean type of... -
An analysis of South African sawmilling competitiveness
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: S Grobbelaar --- , South Africa JK Visser --- , South AfricaThe South African sawn timber market supply and demand are in equilibrium and significantly associated with the local residential construction market. During the great financial crisis (GFC), the local residential construction market contracted. This caused a reduction in sawn timber... -
Residual fertiliser and liming impacts in a long-term Acacia mearnsii trial
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Louis Titshall --- , South AfricaSixth rotation growth measurements of an Acacia mearnsii fertiliser trial established to test the effect of nitrogen (N), phosphorus (P), potassium (K) and lime application on growth and bark production, showed that residual P and lime effects are present. First... -
Reliability and quality of artificial nectar feeders for birds in the Cape Floristic Region
Item type: Journal Article • Journal: Ostrich: Journal of African Ornithology • Authors: Anina Coetzee --- , South Africa Phoebe Barnard --- , South Africa Anton Pauw --- , South AfricaSupplementary feeding of birds may have considerable ecological and evolutionary effects on bird communities. However, there is a lack of basic information on the prevalence, frequency and quality of supplementary feeders, especially in African urban areas. Here we describe the... -
Wood volume estimation strategies for trees from a Dry Forest/Savannah transition area in Piauí, Brazil
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Lailla Sabrina Queiroz Nazareno --- , Brazil Andressa Ribeiro --- , Brazil Mylla Vyctória Coutinho Sousa --- , Brazil Cynthia Wanick Vieira --- , Brazil Antonio Carlos Ferraz Filho --- , BrazilPrediction of aboveground wood volume is one of most important stages when conducting a forest inventory and making forest management decisions. This is more difficult for native forest than for plantations given the high variability of the former (trees of... -
Machine learning and regression models to predict multiple tree stem volumes for teak
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Ivaldo da Silva Tavares Júnior --- , Brazil Jianne Rafaela Mazzini de Souza --- , Brazil Lucas Sérgio de Sousa Lopes --- , Brazil Leonardo Pereira Fardin --- , Brazil Gianmarco Goycochea Casas --- , Brazil Ricardo Rodrigues de Oliveira Neto --- , Brazil Rodrigo Vieira Leite --- , Brazil Helio Garcia Leite --- , BrazilThe quantification of a stand’s wood stock is one of the most important procedures for Tectona spp. (teak) management. An optimal method for estimating tree volume must accommodate the variation of the data collected in the inventory. This study evaluated... -
Charcoal heaps volume estimation based on unmanned aerial vehicles
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Luiza Marina Esteves de Carvalho --- , Brazil Alessandra Melo --- , Brazil Glauco José de Matos Umbelino --- , Brazil Jan-Peter Mund --- , Germany Jhonathan Gomes dos Santos --- , Brazil Jacqueline Rosette --- , United Kingdom Daniel Silveira --- , São Paulo Eric Bastos Gorgens --- , BrazilThe charcoal stock in a forestry business is controlled based on the theoretical capacity of the masonry ovens (input) and shipped trucks (output). During the year, the company must monitor the stock for accountability reports and internal governance. This paper... -
Long‐term variation in reproductive traits of Bibron's agama, agama impalearis, in Western Morocco
Item type: Journal Article • Journal: African Journal of Herpetology • Authors: M. Znari --- Cadi Ayyad University, Morocco E. El Mouden --- Cadi Ayyad University, Morocco H. Francillon‐Vieillot --- Université Denis Diderot Paris 7, Laboratoire d'Anatomie Comparée, FranceFemale reproductive characteristics (clutch size [CS], egg volume [EV] and egg mass [EM]) of Agama impalearis and their annual variation were studied over a six‐year period (1993–1998) in the central Jbilet mountains, Western Morocco. Females produced one to two clutches... -
Long-term study of the drought impact on the phytoplankton concentration and assemblages in two water supply reservoirs in Namibia
Item type: Journal Article • Journal: African Journal of Aquatic Science • Authors: Johannes Sirunda --- Namibia Water Corporation, Namibia Paul Oberholster --- University of the Free State, South Africa Gideon Wolfaardt --- Stellenbosch University, South Africa Christoff Truter --- Toronto Metropolitan University, Canada Sean van der Merwe --- University of the Free State, South AfricaRising temperatures and increased occurrences of droughts, brought on by climate change, are expected to affect reservoir water levels. We hypothesised that the decrease in reservoir volumes in dams with desert climates will favour the growth of phytoplankton biomass, measured... -
Time–frequency analysis of cryptocurrency attention
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Zuzana Kučerová --- VSB-Technical University of Ostrava, Czech Republic Svatopluk Kapounek --- Mendel University in Brno, Czech Republic Jarko Fidrmuc --- Mendel University in Brno, Czech RepublicWe present a wavelet analysis of retail investor attention and the daily returns of Bitcoin, Ethereum, and Litecoin at five selected crypto exchanges that identifies the fractal dynamics of the short- and long-term persistent processes. The investors’ attention is proxied... -
Effects of succinic acid impregnation on physical properties of sapwood and heartwood from plantation-grown short-rotation teak
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Sarah Augustina --- National Research and Innovation Agency (BRIN), Indonesia Teguh Darmawan --- National Research and Innovation Agency (BRIN), Indonesia Sudarmanto --- National Research and Innovation Agency (BRIN), Indonesia Narto Narto --- National Research and Innovation Agency (BRIN), Indonesia Adik Bahanawan --- National Research and Innovation Agency (BRIN), Indonesia Danang S Adi --- National Research and Innovation Agency (BRIN), Indonesia Dimas Triwibowo --- National Research and Innovation Agency (BRIN), Indonesia Yusup Amin --- National Research and Innovation Agency (BRIN), Indonesia Imran A Sofianto --- National Research and Innovation Agency (BRIN), Indonesia Prabu S Sejati --- National Research and Innovation Agency (BRIN), Indonesia Wahyu Dwianto --- National Research and Innovation Agency (BRIN), Indonesia Witjaksono --- National Research and Innovation Agency, Indonesia Ragil Widyorini --- Universitas Gadjah Mada, Philippe Gérardin --- Université de Lorraine, France Sari Delviana Marbun --- National Research and Innovation Agency (BRIN), IndonesiaThe aim of this study was to improve the properties of 15-year-old short rotation teak wood using a succinic acid (SA) treatment without excessively increasing the weight gain. The samples were classified as sapwood (SW) and heartwood (HW). Samples were... -
Effects of thinning on growth performance of teak (Tectona grandis) plantations in Tain II Forest Reserve, Ghana
Item type: Journal Article • Journal: Southern Forests: a Journal of Forest Science • Authors: Bertrand Festus Nero --- Kwame Nkrumah University of Science and Technology, Ghana Maxwell Asuenabisa --- Kwame Nkrumah University of Science and Technology, GhanaAlthough recent interest in commercial teak plantation establishment has soared, knowledge of intensive silvicultural management of residual stands is limited in most parts of West Africa. This study evaluated the effects of thinning regimes on the growth responses and pruning... -
Changes in hepatic volume and body composition following a two-week very low-calorie diet (VLCD) prior to a laparoscopic Nissen fundoplication
Item type: Journal Article • Journal: South African Journal of Clinical Nutrition • Authors: Francis-Mico Price --- University of the Free State, South Africa Francois Nicholaas Schutte --- Zuid-Afrikaans Hospital, South AfricaAn enlarged fatty liver makes laparoscopic surgery of the upper gastrointestinal tract (GIT) more technically challenging. A 35-year-old female was referred to the dietitian for a preoperative very low-calorie diet (VLCD) to assist in decreasing hepatic volume and visceral adiposity... -
Impacts of analyst coverage initiation on market quality
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Yongsik Kim --- Hankuk University of Foreign Studies, Korea Doojin Ryu --- Sungkyunkwan University, KoreaWe examine whether the initiation of financial analysts’ coverage leads to improved stock-price informativeness and increased market liquidity using the difference-in-differences methodology. The average value of daily total trading volume is significantly higher after than before initiation. The increase in... -
The spillover and leverage effects and trading volume of FinTech Exchange-Traded Funds
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Sabbor Hussain --- Chung Yuan Christian University, Taiwan Jo-Hui Chen --- Department of Finance, Chung Yuan Christian University, TaiwanThis paper explores the spillover and leverage effects, as well as trading volume dynamics, of Financial, Technology, and FinTech Exchange-Traded Funds (ETFs) using ARMA-GARCH and ARMA-EGARCH models. The study indicates that these ETF sectors and the stock market index have... -
CEO-related announcements, trading activity, and calendar effects
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Katarzyna Byrka-Kita --- University of Szczecin, Poland Mateusz Czerwiński --- University of Szczecin, PolandThis study examines how abnormal trading volumes reflect new information, such as CEO-related announcements. Using hand-collected data on 1,236 CEO reappointments and turnovers from Polish firms listed on the Warsaw Stock Exchange, we show that investor reaction to CEO-related announcements... -
Public attention, investor sentiment and stock markets: Evidence from Chinese listed firms
Item type: Journal Article • Journal: Investment Analysts Journal • Authors: Renbo Shi --- School of Economics and Management, Beihang University, China Wei Shan --- School of Economics and Management, Beihang University, China Junguang Gao --- , China Changfeng Cheng --- School of Economics and Management, Beihang University, ChinaThe COVID-19 pandemic’s onset introduced unforeseen disruptions to the Chinese stock market. This study uses all A-share companies from 20 January to 26 April 2020, as research samples to explore the impact of public attention on investor sentiment and the... -
Type 2 diabetes mellitus but not overweight/obesity reduces testicular volume and endocrine function in men
Item type: Journal Article • Journal: Journal of Endocrinology, Metabolism and Diabetes of South Africa • Authors: E Musa --- Kaduna State University, Nigeria GC Musa --- University of Cape Town, South Africa E Salazar-Petres --- Universidad San Sebastián, Carrera de Obstetricia, Chile F Bello --- Ahmadu Bello University, Nigeria AG Bakari --- Ahmadu Bello University, Nigeria -
Umbilicity of complete linear Weingarten hypersurfaces immersed in certain Einstein manifolds
Item type: Journal Article • Journal: Quaestiones Mathematicae • Authors: Henrique F. de Lima --- Universidade Federal de Campina Grande, Brazil Lucas S. Rocha --- Universidade Federal de Campina Grande, Brazil Marco Antonio L. Velásquez --- Universidade Federal de Campina Grande, BrazilIn this paper, we present some sets of geometric conditions that ensure the umbilicity of linear Weingarten hypersurfaces immersed in an Einstein manifold satisfying standard curvature constraints which, in particular, are verified by a Riemannian space with constant sectional curvature...