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1.
J Environ Manage ; 229: 158-165, 2019 Jan 01.
Article in English | MEDLINE | ID: mdl-29861091

ABSTRACT

The negative effects of invasive alien species (IAS) are increasingly invoked to justify widespread and usually top-down approaches for their management or eradication. However, very little of the research or discourse is based on investigating local perceptions, uses and struggles with IAS, and how their presence influences and changes local livelihoods. The objective of this study was to assess the perceptions and livelihood uses of Acacia dealbata by local communities at three localities in the montane grasslands of the Eastern Cape, South Africa, using a combination of random household interviews, focus group discussions and participatory tools. We calculated direct-use values for each product and household (based on quantity used and local prices) and disaggregated these by gender of the household head and wealth quartiles. The results revealed the dualistic role of A. dealbata in local livelihoods. On the one hand, A. dealbata was widely used for firewood (100% of households), tools (77%) and construction timber (73%), with limited use for traditional medicines and forage. The cumulative value of approximately ZAR 2870 (±US$224) per household per year (across all households) represents considerable cash saving to households, most of whom are quite poor by national and international measures. On the other hand, the increasing extent of A. dealbata (93% said it was increasing) exacerbates local household vulnerability though reported reductions in cultivated areas, crop yields and forage production, and allegedly higher risks of crime. This quandary is well encapsulated by the considerable majority of respondents (84%) not wanting higher extents and densities of A. dealbata, but an equally high majority not wanting its total removal from local landscapes. Most respondents disliked A. dealbata in fields, close to homesteads or along primary access routes, and were more tolerant of it away from such sites. Institutional and use dynamics have varied over several decades in response to the changing extent and densities of A. dealbata and the broader political and socio-economic contexts. These results indicate that greater efforts are required to understand perceptions and uses of IAS by the people who live with them, and to direct such understanding into more spatially and temporally contextualised response strategies where required.


Subject(s)
Introduced Species , Acacia , Cost-Benefit Analysis , Family Characteristics , Focus Groups , Humans , Introduced Species/economics , Rural Population , South Africa , Trees
2.
Environ Manage ; 55(2): 411-22, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25371193

ABSTRACT

Understanding the rates and causes of land-use change is crucial in identifying solutions, especially in sensitive landscapes and ecosystems, as well as in places undergoing rapid political, socioeconomic or ecological change. Despite considerable concern at the rate of transformation and degradation of the biodiversity-rich Albany Thicket biome in South Africa, most knowledge is gleaned from private commercial lands and state conservation areas. In comparison, there is limited work in communal areas where land uses include biomass extraction, especially for firewood and construction timber. We used aerial photographs to analyze land use and cover change in the high- and low-use zones of an urban commonage and an adjacent protected area over almost six decades, which included a major political transition. Field sampling was undertaken to characterize the current state of the vegetation and soils of the commonage and protected area and to determine the supply and demand for firewood and construction timber. Between the 1950s and 1980s, there was a clear increase in woody vegetation cover, which was reversed after the political transition in the mid-1990s. However, current woody plant standing stocks and sustainable annual production rates are well above current firewood demand, suggesting other probable causes for the decline in woody plant cover. The fragmentation of woody plant cover is paralleled by increases in grassy areas and bare ground, an increase in soil compaction, and decreases in soil moisture, carbon, and nutrients.


Subject(s)
Trees/growth & development , Urban Renewal , Wood/growth & development , Ecosystem , Environment , Socioeconomic Factors , South Africa , Urban Renewal/economics , Wood/economics
3.
Philos Trans R Soc Lond B Biol Sci ; 369(1639): 20120288, 2014 Apr 05.
Article in English | MEDLINE | ID: mdl-24535394

ABSTRACT

Achieving food security in a 'perfect storm' scenario is a grand challenge for society. Climate change and an expanding global population act in concert to make global food security even more complex and demanding. As achieving food security and the millennium development goal (MDG) to eradicate hunger influences the attainment of other MDGs, it is imperative that we offer solutions which are complementary and do not oppose one another. Sustainable intensification of agriculture has been proposed as a way to address hunger while also minimizing further environmental impact. However, the desire to raise productivity and yields has historically led to a degraded environment, reduced biodiversity and a reduction in ecosystem services (ES), with the greatest impacts affecting the poor. This paper proposes that the ES framework coupled with a policy response framework, for example Driver-Pressure-State-Impact-Response (DPSIR), can allow food security to be delivered alongside healthy ecosystems, which provide many other valuable services to humankind. Too often, agro-ecosystems have been considered as separate from other natural ecosystems and insufficient attention has been paid to the way in which services can flow to and from the agro-ecosystem to surrounding ecosystems. Highlighting recent research in a large multi-disciplinary project (ASSETS), we illustrate the ES approach to food security using a case study from the Zomba district of Malawi.


Subject(s)
Agriculture/methods , Climate Change , Conservation of Natural Resources/methods , Ecosystem , Food Supply/methods , Population Growth , Agriculture/trends , Conservation of Natural Resources/trends , Malawi
4.
J Environ Manage ; 92(6): 1449-60, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21251751

ABSTRACT

Municipal commonages surround many small towns throughout South Africa, and are an integral component of the national land reform programme. But little is known about their extent, use or value, and most appear to have limited or no management or investment. This paper reports on a survey of randomly selected households in three small towns in the Eastern Cape to ascertain the extent and purpose of use of municipal commonages. Between 27% and 70% of urban households used commonage depending on site. Key resources used were fuelwood, medicinal plants, and grazing of livestock. Typically, commonage using households were poorer and less educated than other urban residents, although the profile of users is unique for each town. Given the extensive use of commonage resources, and their contribution to the livelihoods of the poor, local municipalities need to develop and implement sound management strategies that account for all users of commonages, rather than the oft encountered focus on livestock owners and production.


Subject(s)
Agriculture/methods , Conservation of Natural Resources/methods , Urban Population , Data Collection , Humans , Socioeconomic Factors , South Africa
5.
J Environ Manage ; 83(4): 416-26, 2007 Jun.
Article in English | MEDLINE | ID: mdl-16930808

ABSTRACT

Fuelwood is the primary energy source for domestic purposes throughout the developing world, in both urban and rural environments. Due to the detrimental impacts of biomass use on human and environmental health, many governments have sought to reduce its use through provision of potentially cleaner energies, of which electricity is the dominant form. Yet there are surprisingly few studies of changes in fuelwood use following the introduction of electricity, especially in rural areas of Africa. This paper reports on a longitudinal study of fuelwood use, using identical approaches, in five rural villages in the Bushbuckridge region of South Africa, spanning the period over which electricity became widely available. Almost a decade after the introduction of electricity, over 90% of households still used fuelwood for thermal purposes, especially cooking, and the mean household consumption rates over the 11-year period had not changed, even with a policy of 6 kWh per month of free electricity. The proportion of households purchasing fuelwood had increased, probably in response to a number of factors, including (i) increased fuelwood scarcity in the local environment as reflected by increased fuelwood collection times, changes in fuelwood species preferences, and ranking of scarcity by local collectors, and (ii) increases in the price of fuelwood well below that of other fuels and the prevailing inflation rate. Overall, there was an increase in the number of species harvested over the 11-year period. The implications of these findings for rural energy provision are discussed.


Subject(s)
Electricity , Energy-Generating Resources , Wood , Cooking , Heating , Humans , Rural Population , South Africa , Trees
6.
Clin Transpl ; : 189-95, 1994.
Article in English | MEDLINE | ID: mdl-7547538

ABSTRACT

Graft and patient survival rates for Black patients were higher than for any group. This may be due to the younger age distribution among Black transplant recipients versus other races at UCLA. Graft and patient survival for Asian patients were significantly lower than for any other group. However, this result was not totally accounted for by the rapid recurrence of disease in hepatitis B patients. Patients with a positive flow cytometry crossmatch had significantly lower first and second graft survival rates due to early graft loss. Patients with PRA of more than 10% had a higher proportion of positive flow crossmatches. However, as a group, patients with more than 10% PRA did not demonstrate decreased graft survival. Consideration should be given to prospectively flow crossmatching the more than 10% PRA group. Patients with zero-DR mismatches had better survival than patients with one- and 2-DR mismatches. Prospective HLA matching in OLT patients is not currently done.


Subject(s)
Liver Transplantation/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Demography , Female , Graft Survival , Histocompatibility , Hospitals, University/statistics & numerical data , Humans , Infant , Infant, Newborn , Liver Transplantation/immunology , Liver Transplantation/mortality , Los Angeles/epidemiology , Male , Middle Aged , Racial Groups , Reoperation/statistics & numerical data , Retrospective Studies , Treatment Outcome
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