Rangeland Ecology & Management
Get reliable science
Toggle Search
Result Type
Collection
Keywords
Document Type
Displaying 151 - 200 of 206 results
- Library Collection RecordThis paper investigates the predictability of the soil erodibility factor (K) in the revised universal soil loss equation from soil clay content (C), the Naperian logarithm of the geometric mean…Publication Date 1997
- water erosion
- soil erodibility
- Revised Universal Soil Loss Equation
- Fuzzy logic
- Fuzzy erodibility
- Erosion prediction
- Erosion uncertainty
- soil erosion
- modelling
- Africa
- Library Collection RecordA near real-time crop-specific drought monitoring system that combines crop modelling and a geographical information system (GIS) has been developed in South Africa. The system is intended to provide…Publication Date 1997
- agriculture
- drought
- modelling
- GIS
- decision support systems
- monitoring
- Africa
- Library Collection RecordWe present an operational two-source (soil+vegetation) model for evaluating the surface energy balance given measurements of the time rate of change in radiometric surface temperature (TRAD) during…Publication Date 1997
- remote sensing
- modelling
- GIS
- temperature
- surface vegetation
- Africa
- Library Collection RecordThe amount and quality of inputs into soil organic matter will be altered by both climate and landuse change. The increase in growth of plants caused by increasing CO2 concentration implies not only…Publication Date 1997
- elevated carbon dioxide
- Decomposition
- organic residues
- secondary chemicals
- soil organic carbon
- climate change
- land use
- plant autecology
- carbon dioxide
- modelling
- ecosystem dynamics
- ecosystem ecology
- plant production
- management
- Africa
- Library Collection RecordPolycultural agroecosystems, such as rangelands, are too complex and poorly understood to permit precise numerical simulation. Management decisions that depend on behavioral predictions of such…Publication Date 1996
- Case-based reasoning (CARMA)
- Model-based reasoning
- prediction
- ecosystem
- Reasoning paradigms
- pest management
- rangelands
- ecosystem ecology
- modelling
- ecosystem dynamics
- management
- decision support systems
- Africa
- Library Collection RecordAlien plants invade many ecosystems worldwide, often having substantial negative effects on ecosystem structure and functioning. The apparent complexity of invasions has impaired the development of a…Publication Date 1996
- biological invasions
- Model comparison
- Plant dispersal
- Alien invasive species
- modelling
- management
- decision support systems
- ecosystem ecology
- Africa
- Library Collection RecordSPUR (Simulation of Production and Utilization of Rangelands) is a physically-based model designed to simulate the complexity of rangeland ecosystems (Wight and Skiles, 1987). Results of extensive…Publication Date 1996
- model evaluation
- Rangeland ecosystems
- Spur
- modelling
- management
- soils
- temperature
- livestock
- Africa
- Library Collection RecordRiver salination due to dryland agriculture was studied between 1985 and 1986 in the 150-km2 large catchment of the Sandspruit river, a tributary of the Berg river in the semi-arid Western Cape…Publication Date 1995
- agriculture
- hydrology
- rainfall
- modelling
- soils
- Africa
- Library Collection RecordDensities of large herbivores within distance annuli around drinking troughsin the Kruger National Park were determined by means of aerial counts. A relationship between herbivore use intensity and…Publication Date 1995
- herbivores
- density
- Watering Point
- Kruger National Park
- modelling
- national parks
- animal impact
- rangeland condition
- Africa
- Library Collection RecordThis paper describes the development of a model for estimating herbage production from rainfall and evapotranspiration in rangelands and its calibration using a vegetation cover index derived from…Publication Date 1995
- rangelands
- modelling
- herbage production
- grazing
- land degradation
- degradation
- plant production
- rainfall
- remote sensing
- rangeland condition
- Africa
- Library Collection RecordThe Integrated System for Plant Dynamics (ISPD) is a comprehensive system in which new and existing data and knowledge are quantitatively or qualitatively used as a basis for range condition and…Publication Date 1995
- Integrated System for Plant Dynamics
- range condition
- grazing capacity
- southern Africa
- Eastern Mixed Bushveld
- grazing
- modelling
- savanna
- rangeland condition
- management
- degradation
- Africa
- Library Collection RecordThis paper describes methods to couple the reflectance-resistance model developed in Paper I with the normalized difference vegetation index (NDVI) data from the advanced very high resolution…Publication Date 1995
- NDVI values
- remote sensing
- rainfall
- drought
- modelling
- grasslands
- pollution
- Africa
- Library Collection RecordNo abstract availablePublication Date 1995
- ecosystem dynamics
- degradation
- savanna
- modelling
- Africa
- Library Collection RecordCows are important agents of geomorphological change. On the uplands, heavy grazing compacts the soil, reduces infiltration, increases runoff, and increases erosion and sediment yield. However, light…Publication Date 1995
- cattle
- ecosystem dynamics
- Soil Condition
- runoff
- soil erosion
- grazing
- modelling
- Africa
- Library Collection RecordRemote sensing applications used for resource assessment often lack the capacity to test image data against predictions. This article describes remote environment and management assessment (REMA), a…Publication Date 1995
- remote sensing
- Landsat images
- rangelands
- animal impact
- fodder production
- modelling
- Africa
- Library Collection RecordDevelopment and use of crop growth simulation models has increased in the last decades. Most crop growth models require daily weather data as input values. These data are not easy to obtain and…Publication Date 1994
- agriculture
- modelling
- plant production
- data analysis
- climate
- Africa
- Library Collection RecordThe temporal and spatial distribution of African savanna grassland fires has been examined, and the areal extent of these fires has been estimated for the subequatorial African continent. African…Publication Date 1994
- grasslands
- fire ecology
- GIS
- modelling
- Africa
- Library Collection RecordThis article is the continuation of a study of the relationship between NDVI and rainfall in semiarid Botswana. That study notes significant differences in the NDVI-rainfall relationship for various…Publication Date 1994
- modelling
- NDVI values
- rainfall
- soils
- Africa
- Library Collection RecordThis paper presents results of a deforestation experiment carried out with the general circulation model of the Laboratoire de Météorologie Dynamique coupled to the Schématisation des Echanges…Publication Date 1994
- modelling
- land use
- environmental factors
- soils
- soil moisture
- grasslands
- Africa
- Library Collection RecordFour deterministic rainfall-runoff models are briefly described and applied to a small (0.18 km2) grassland catchment in the Eastern Cape Province of South Africa. The models vary in complexity, from…Publication Date 1994
- rainfall
- runoff
- soil erosion
- grasslands
- modelling
- Africa
- Library Collection RecordAn analysis tool was developed to simulate primary productivity and crop yields for both present and possible future climate conditions. Southern Africa was delineated into 712 relatively homogeneous…Publication Date 1993
- plant production
- agriculture
- climate change
- soil
- vegetation dynamics
- hydrology
- modelling
- GIS
- rainfall
- socio-economic aspects
- policies
- food security
- Africa
- Library Collection RecordA utilitarian simulation model of botanical composition of ruminant diets on rangelands is proposed. It emphasizes the use of forage resource diversity within the range ecosystem context. The forage…Publication Date 1993
- modelling
- Forage Quantity
- rangelands
- species richness
- biodiversity
- cattle
- forage quality
- livestock
- grazing
- ecology
- Africa
- Library Collection RecordThe role of empiricism in predicting mean annual primary production at the mesoscale is demonstrated through development of a simple model (RESAP) for application over all land surfaces within a…Publication Date 1993
- savanna
- modelling
- plant production
- mapping
- agriculture
- Africa
- Library Collection RecordA multiple-source surface energy balance model for use in general circulation models (GCMs) is developed. The model recognizes three biome architectures: closed canopies (e.g. forest), biomes with…Publication Date 1993
- ecology
- modelling
- soils
- agriculture
- Africa
- Library Collection RecordSpatial dependence is a fundamental structure of spatial data that can be readily measured. Change in landscapes can be monitored effectively using measures of spatial dependence. Scale of…Publication Date 1993
- grasslands
- grazing
- modelling
- Landsat images
- remote sensing
- Africa
- Library Collection RecordThe advantages of incorporating variable length time steps into deterministic hydrological models are discussed and a method based on the use of rainfall thresholds to determine appropriate length…Publication Date 1993
- hydrology
- rainfall
- modelling
- grasslands
- Africa
- Library Collection RecordNo abstract availablePublication Date 1992
- rangelands
- modelling
- decision support systems
- Africa
- Library Collection RecordThis paper describes the development and initial validation of a simulation model designed to predict patterns of landscape use by cattle as a function of environmental conditions and spatial…Publication Date 1992
- modelling
- cattle
- landscape ecology
- animal impact
- grazing
- water use efficiency
- temperature
- Africa
- Library Collection RecordPartitioning available energy between plants and bare soil in sparsely vegetated rangelands will allow hydrologists and others to gain a greater understanding of water use by native vegetation,…Publication Date 1992
- rangelands
- hydrology
- ecosystem ecology
- modelling
- Africa
- Library Collection RecordIn this paper, the second part of a two-part series, the performance of a quasi-physically based rainfall-runoff model (QPBRRM) is evaluated for a set of 39 events from a small rangeland catchment (R…Publication Date 1992
- rainfall
- runoff
- rangelands
- soil moisture
- modelling
- ecology
- Africa
- Library Collection RecordThis paper, the first part in a two-part series, is concerned with the interpretation of spatial and temporal variations in soil water content across a small rangeland catchment; two data sets are…Publication Date 1992
- rainfall
- runoff
- rangelands
- soil moisture
- modelling
- Africa
- Library Collection RecordThree years of weekly measurements of surface runoff and sediment yield from two small plots in a dune terrain along the Dutch coast have been used to model water erosion. The measurements of the…Publication Date 1991
- runoff
- rainfall
- erosion
- modelling
- Soil Condition
- Africa
- Library Collection RecordA conceptual model of the pastoral production system within the arid, winter rainfall shrublands of Western Australia is described. The building blocks of this model are pasture-type models which are…Publication Date 1991
- modelling
- plant production
- animal production
- soils
- pasture management
- Africa
- Library Collection RecordVegetative cover affects the spatial and temporal variability of heat and water in the soil. The ability to predict temperature and water conditions enhances our ability to evaluate management…Publication Date 1991
- modelling
- soils
- ecosystem dynamics
- ecosystem ecology
- Africa
- Library Collection RecordA mathematical model is presented of the subsistence pastoral system on the Makatini Flats surrounding the Pongola floodplain just south of the Mozambique border in north-eastern South Africa. The…Publication Date 1990
- modelling
- management
- subsistence agriculture
- pastoralism
- land use
- grazing
- irrigation
- Africa
- Library Collection RecordThe SPUR (simulation of production and utilization of rangelands) model was evaluated for use on eastern hill land pastures. The model was calibrated using the first year of soil fertility, weather,…Publication Date 1990
- rangelands
- Soil Condition
- cattle
- modelling
- animal production
- plant production
- Africa
- Library Collection RecordThe numbers of dead cattle in 1977/1978-1985/1986, expressed as a percentage of the total cattle numbers, for six regions in Botswana and for the country as a whole, were analysed as a function of a…Publication Date 1990
- cattle
- water use efficiency
- drought
- rainfall
- modelling
- soil moisture
- Africa
- Library Collection RecordInformation from the literature about forage conservation losses in the field has been reviewed, contrasted and analysed in the categories respiratory loss, leaching loss and mechanical loss. An…Publication Date 1989
- forage quality
- conservation
- agriculture
- modelling
- temperature
- rainfall
- Africa
- Library Collection RecordPreviously described forage and beef models were used to investigate the biological productivity of continuous (CG) and rotational grazing (RG) systems on common bermudagrass (Cynodon dactylon (L.)…Publication Date 1989
- cattle
- foraging ecology
- modelling
- animal production
- management
- stocking rates
- grazing
- grasslands
- Africa
- Library Collection RecordRangeland areas are characterized by sparse and limited hydrological data that make the use of existing mathematical runoff models difficult and impractical. A simple rational mathematical model was…Publication Date 1989
- Runoff modeling
- Hydrological modeling
- Runoff simulation
- Snowmelt modeling
- rangeland hydrology
- modelling
- rainfall
- rangelands
- runoff
- Africa
- Library Collection RecordA plant growth model has been developed as a component of a general rangeland production and utilization model (SPUR). The carbon and nitrogen content of standing green, live roots, propagules,…Publication Date 1988
- modelling
- rangelands
- animal production
- plant production
- management
- Africa
- Library Collection RecordNOAA-6 and NOAA-7 Advanced Very High Resolution Radiometer (AVHRR) global-area coverage (4 km ground resolution) data were obtained at three-day intervals throughout each of the four-month periods…Publication Date 1987
- remote sensing
- NOAA
- rainfall
- drought
- modelling
- Africa
- Library Collection RecordPasture production not only depends on precipitation amount and distribution patterns, but also on soil type and evaporative demand. The simulation model of Rose et al., developed using improved…Publication Date 1987
- pasture management
- fertilizer
- rainfall
- soil classification
- modelling
- Africa
- Library Collection RecordGrassland burning elicits a diverse array of responses by arthropods, depending upon many interactive factors. Empirical models were developed, based on the literature, to qualitatively order…Publication Date 1987
- grasslands
- fire ecology
- insects
- modelling
- ecosystem ecology
- Africa
- Library Collection RecordThe literature suggests that two different approaches have been applied to problems of rangeland monitoring using MSS data. These are referred to as the near infrared over red ratio which has been…Publication Date 1987
- remote sensing
- rangeland condition
- savanna
- modelling
- Africa
- Library Collection RecordThe growth functions required for the simulation of production in Themeda triandra grassland were developedfor the PUTU 11 growth model. The model was developed using veld production data collected…Publication Date 1986
- Carbohydrate
- crop growth model grassland simulation
- modelling
- PUTU 11
- Africa
- Library Collection RecordLandsat data were simulated for a three-component rangeland scene consisting of grass, brush, and soil to evaluate the effect of soil background reflectance on the sensitivity of ratio and orthogonal…Publication Date 1986
- Landsat images
- rangelands
- soil
- modelling
- Africa
- Library Collection RecordA mathematical model is presented of the regional cattle herd within a subsistence pastoral system, in a semi-arid region, where empirical data on herd production are restricted to a few basic…Publication Date 1985
- modelling
- Economic Aspects
- cattle
- subsistence agriculture
- pastoralism
- stocking rates
- Africa
- Library Collection RecordNine plant growth models for grassland ecosystems were examined. Model objectives, complexity and inclusiveness were compared. A large degree of diversity in model complexity and structure exists in…Publication Date 1985
- grasslands
- modelling
- ecosystem dynamics
- grazing
- Africa
- Library Collection RecordA model of kleingrass (Panicum coloratum L.) growth and utilization by steers is presented. The model included stochastic inputs of climatological characteristics, water retention at different soil…Publication Date 1984
- modelling
- cattle
- grazing
- grasslands
- animal nutrition
- plant production
- stocking rates
- decision support systems
- Africa