50 research outputs found
A Bioeconomic Stocking Rate Model for the Semi-Arid Savanna of Natal, South Africa
Grazing trials were conducted on 2 sites located In semi-arid savanna of Natal. Three stocking strategies were applied at each site to provide light, intermediate and heavy stocking. Data collected over 5 seasons were used to.develop a bioeconomic stocking rate model. While individual animal performance and nett return per livestock unit (R/LSU) decreased with increased stocking, net return per ha (Riha) increased, Net return was significantly related (P 0, 01) to rainfall and stocking rate, while no significant effect of range condition was detected. Although Increased stocking may be justified In the short• term, this may be associated with both. Increased ecological and financial risk and may not be sustainable in the long-term
Institutions and governance of communal rangelands in South Africa
The creation of local institutions with a mandate over land access and control is seen as a prerequisite for successful decentralisation of land tenure and effective local resource management in sub-Saharan Africa. However, with land tenure reform in South Africa currently at a state of legislative impasse, real uncertainty now exists over land rights and governance of rangeland in many communal areas. This paper draws on case study material from Eastern Cape province to illustrate how this ongoing uncertainty has resulted in the operation of a range of traditional authority and civil society institutions in different communal areas with varying degrees of legitimate authority over land administration and highly variable performance in managing rangeland resources. Collective management of rangeland resources seems most difficult in environments where land rights are contested because of the coexistence of traditional leaders and civil society institutions. On this basis an approach to tenure reform is advocated, which vests all powers over local land administration in democratically elected and accountable civil society institutions. Some successful examples of this already exist and might serve to guide policy formation, which must be flexible enough to accommodate collective management approaches that emphasise cooperation both within and between communities.Keywords: common property, land tenure, natural resource management, traditional leadersAfrican Journal of Range & Forage Science 2013, 30(1&2): 77–8
Ammonium Nitrogen Patterns in Soils of a Pennisetum clandestinum Pasture and its Reaction to Nitrogen Fertilizers
Soil ammonium N concentration within the profile of a Pennisetum clandestinum (kikuyu) pasture was higher at 0-10 cm and 75-100 cm than at intermediate depths. This contrasted with the pattern in the same soil from an adjacent maizeland. Here, ammonium N concentrations declined with depth, reaching their lowest concentration at 75-100 cm. Soil ammonium N concentrations increased with increasing N applications
Volatilized Nitrogen from a Tropical Pennisetum clandestinum Pasture in South Africa
A micrometeorological mass balance was used to determine nitrogen volatilised as ammonia from dryland Pennistetum clandestinum (kikuyu) pasture. Treatments included 2 levels of N {ISO and 300 kgN/ha, applied in 3 dressings) from limestone ammonium nitrate and urea. Volatilised N was measured after N application and during subsequent grazing periods. Overall, volatilised N was lower than expected for subtropical conditions (4.4% of applied N). Higher losses were recorded when sward height was reduced from IO cm to 3 cm. The mean difference was 764±109 gN/ha {P.05) for 33 h after the application of urea at 50 kg N/ha
Range Management: Optimizing Forage Production and Qualityy
Range management involves optimising forage production and quality, both in the short term and in the long term. In the short term, temporal climatic variability, stocking rate, grazing system, fire, animal type. and spatial variability, inter alia, strongly, influence forage production and quality. On the other hand, long-term optimisation requires prevention of range deterioration. The nature of this process seems to be profoundly different between humid and arid rangelands, at least in tropical and subtropical zones. In the former, changes are relatively predictable, overgrazing resulting in gradual deterioration. In the latter, change is event driven, providing the grazier with long periods of system inertia interspersed randomly by risks and opportunities to cause or prevent community change from one state to another. Management for long-term sustainability often requires sacrifice of short-term welfare. The benefits of such management may even be beyond the planning horizon of the grazier. Implementing conservation thus requires altruism on the part of the grazier - an unlikely option. If society requires such conservation, it may need to ainend its values, and either provide the grazier with an incentive, or outlaw overgrazing