Vegetation change analysis and ecological recovery of the copperbelt Miombo woodland of Zambia

Thesis (PhD (Forest and Wood Science))--University of Stellenbosch, 2009.ENGLISH ABSTRACT: The study aimed at developing a new understanding of the Miombo woodland recovery dynamics when exposed to single tree selection, slash & burn agriculture and charcoal production. Five specific studies were conducted to examine different parts of this overall study: Miombo woodland utilization, management and conflict resolution among stakeholders; speciesstem curves as a tool in sampling the development of Miombo woodland species richness in charcoal and slash & burn regrowth stands over time; the impact of human disturbance on the floristic composition of Miombo woodland; regeneration and recruitment potentials of key Miombo woodland species after disturbance; and age and growth rate determination using selected Miombo woodland species. Different methods were developed for each specific study. The study of woodland utilization and management employed semi-structured and key informant interviews. STATISTICA statistical package version 6.0 was used for data collation and analysis. Chi-square tests were used to show levels of significance in differences that existed between different user groups. Species-stem curves were used to determine the sample size to assess Miombo woodland dynamics in regrowth stands after slash & burn and charcoal production, and a fixed-area method was used for the mature woodland stands. The study sites in each of three study areas were selected to represent ages ranging from 2 to 15+ years since each disturbance was terminated. The undisturbed woodland was chosen to act as a control. Various analyses using the STATISTICA statistical package and CANOCO version 4.0 were conducted to understand responses of Miombo woodland to these different disturbances. The research revealed that single tree selection, slash & burn agriculture and charcoal production are the main forms of Copperbelt Miombo woodland utilization which will always be there. Additionally, the the Miombo woodland stands were characterized based on the size class profile they exhibit on exposure to human disturbance factors through forest utilization. The characterization has revealed that the woodland is dominated by light demanding species. As such single tree selection harvesting does not support the regeneration and establishment of the timber species which are canopy species under shade conditions. This implies that selection harvesting of timber species, although it appears to be a non event in terms of disturbance at stand level may be a disaster at population level. The study also revealed that clearing of the woodland for either slash & burn agriculture or charcoal production results in enhanced regeneration and establishment of the dominant Miombo woodland species. The study concludes that charcoal production and slash & burn agriculture are important components to which the woodland ecosystem is adapted. As such these disturbance factors may be considered as incorporated disturbances. It is recommended from the study that woodland utilization and management should integrate charcoal production and slash & burn agriculture into forest management. Cutting cycles should be based on growth rate of the selected species. Timber species harvesting should go side by side with these disturbance factors so as to open up the canopy in order that maximum sunlight can reach the regeneration stock. The study also brings out the other management and utilization opportunities (such as managing for Uapaca kirkiana and Anisophyllea boehmii fruits) that arise from different development stages of the woodland. Lastly, it is recommended to ascertain the optimum gap sizes for both charcoal production or slash & burn agriculture which would still support the Miombo woodland recovery.AFRIKAANSE OPSOMMING: Hierdie studie is gedoen om ‘n nuwe begrip te ontwikkel vir die hersteldinamika van Miombo boomveld na onderwerping aan enkelboomseleksie, kap & brand lanbou en houtskoolproduksie. Vyf spesifieke studies is gedoen om verskillende komponente van die total studie te ondersoek: benutting, bestuur en konflikresolusie tussen gebruikers van Miombo boomveld; species-stam kurwes as ‘n instrument in die bemonstering van die ontwikkeling van Miombo boomveld species-rykdom oor tyd na afloop van houtskoolproduksie en kap & brand landbou; die impak van menslike versteuring op die floristiese samestelling van Miombo boomveld; verjongingspotensiaal van sleutelsoorte in Miombo boomveld na versteuring; en bepaling van ouderdom en groeitempo in ge-selekteerde Miombo boomveldsoorte. Verskillende metodes is ontwikkel vir elke spesifieke studie. In die studie van boomveldgebruik en –bestuur is semigestruktureerde en sleutel-informant onderhoude gebruik. Die STATISTICA statistiese packet weergawe 6.0 is gebruik vir dataverwerking en -ontleding. Chi-kwadraat toetse is gebruik om vlakke van betekenisvolheid te toon wat bestaan tussen verskillende gebruikersgroepe. Speciesstamkruwes is gebruik om monstergrootte te bepaal vir die evaluering van Miombo boomvelddinamika in hergroeiopstande na kap & brand en houtskoolproduksie, terwyl vastegrootte persele gebruik is vir volwasse boomveldopstande. Die studieplekke in elk van drie studiegebiede is geselekteer om verskillende ouderdomme tussen 2 en 15+ jaar na be-eindiging van die versteuring te verteenwoordig. Onversteurde boomveld is gebruik as kontrole. Verskeie ontledings, met die STATISTICA statistiese pakket en CANOCO weergawe 4.0 is gedoen om die reaksie van Miombo boomveld op die verskillende versteurings te verstaan. Die navorsing het getoon dat enkelboomseleksie, kap & brand landbou en houtskoolproduksie is die hoof vorme van Copperbelt Miombo boomveld benutting wat altyd daar sal wees. Verder is die Miombo boomveldopstande gekarakteriseer gebaseer op die grootteklasprofiel wat hulle vertoon na menslike versteuringsfaktore in die vorm van boomveldbenutting. Die karakterisering het getoon dat die boomveld gedomineer word deur ligeisende soorte. Daarom ondersteun enkelboomseleksie nie die verjonging en vestiging van die dominante houtsoorte wat kroonsoorte is onder skadutoestande. Dit impliseer dat selektiewe inoesting van houtsoorte, alhoewel dit voorkom as ‘n onbelangrike gebeurtenis in terme van versteuring op opstandsvlak, ‘n ramp is op populasievlak. Die studie het ook getoon dat skoonmaak van die boomveld vir of kap & brand landbou of houtskoolproduksie, lei tot verbeterde verjonging en vestiging van die dominante Miombo boomveldsoorte. Die studie lei tot die gevolgtrekking dat houtskoolproduksie en kap & brand landbou belangrike komponente is waarby die boomveldsisteem aangepas is. Daarom kan hierdie versteuringsfaktore beskou word as ingeslote versteurings. Vanuit die studie word daarom aanbeveel dat boomveldbenutting en –bestuur houtskoolproduksie en kap & brand landbou binne die bosbestuur integreerd moet word. Kapsiklusse moet gebaseer word op die groeitempos van geselekteerde soorte. Inoesting van houtsoorte moet saamloop met hierdie versteuringsfaktore sodat die kroondak oopgemaak kan word sodat maksimum sonlig die verjonging bereik. Die studie bring ook na vore die bestuur en benuttingsgeleenthede (soos bestuur vir die vrugte van Uapaca kirkiana en Anisophyllea boehmii) wat voorkom in verskillende ontwikkelingstadiums van die boomveld. Laastens word aanbeveel dat die optimum openinggroottes vir beide kap & brand en houtskoolbereiding wat herstel van Miombo boomveld ondersteun, bepaal

Physico-chemical characteristics and heavy metal concentrations of copper mine wastes in Zambia: implications for pollution risk and restoration

Soil characterization is a vital activity to develop appropriate and effective restoration protocols for mine wastelands while insights into the total content of heavy metals in the soil is an important step in estimating the hazards that the metals may pose to the vital roles of soil in the ecosystem. This study addressed the following research questions: (1) To what extent do the physico-chemical characteristics vary between mine waste sediments and the nearby forest soil? (2) Are the concentrations of heavy metals high enough to be considered as toxic? and (3) Are heavy metals present in mine waste sediments potential sources of pollution? We hypothesized that the physico-chemical characteristics of mine waste sediments are less favorably for plant establishment and growth while the concentrations of heavy metals are very high, thus restricting the success of revegetation of mine waste lands. Mine waste sediments were sampled following a diagonal transect across tailings dams, overburden dump sites and the local forest soil from the top layer (0-20 cm) using a closed auger. Samples were analyzed for arsenic, barium, lead, cadmium, cobalt, copper, chromium, nickel, vanadium, and zinc as well as for soil physico-chemical properties. The mine waste sediments were dominated by silt whilst the forest soil by sand particles, with significantly high bulk density in the former. Both the forest soil and overburden sediments were acidic than the alkaline tailings dam sediment. Total organic carbon and nitrogen contents were significantly low in mine wasteland substrates but the concentration of Ca and Mg were significantly higher in tailings dam substrate than the forest soil. The concentrations of available P, K and Na were similar across sites. The mean concentrations of heavy metals were significantly (p < 0.01) higher in mine waste sediments than the forest soil; except for cadmium (p = 0.213). The order of contamination by heavy metals on the tailings was Cu > Co > Ba > Ni > As > Zn > Pb > Cr > V > Cd, and that on the overburdens was Cu > Co > Ba > Ni > Zn > Cr > Pb > V > As > Cd. The pollution load index (PLI) was nearly twice higher for the tailings dam (8.97) than the overburden (5.84). The findings show that the copper mine wastes (the tailings dams and overburden waste rock sites) are highly contaminated by heavy metals; which, in turn, might pose serious hazards to human health and agricultural productivity. In addition, poor macro-nutrient availability, substrate compaction and soil acidity (particularly on overburden sites) coupled with toxic level of heavy metals would be the main challenges for successful phytostabilization of copper mine wastelands

A review of carbon dynamics and assessment methods in the miombo woodlands

Provision of accurate carbon (C) measurements and analysis are critical components in quantification of C stocks. The objectives of this review are to (a) compile and synthesis current knowledge of available methods for C stock estimation (b) examine socio-economic drivers of land use and land cover change and their influence on woodland C stocks and (c) identify gaps of knowledge and methodological inadequacies in understanding factors affecting C stocks of major C pools namely: aboveground, belowground and soil C pools for miombo woodlands of Southern Africa. major C pools. We reviewed and evaluated a wide range of literature from peer reviewed articles. It was evident from the review that quantification of forest C is a challenging task, mainly associated with knowledge gaps and methodological challenges. This has brought about a high level of uncertainty and inconsistencies, mainly due to the accounting methods applied. We emphasise that comprehensive understanding of socio-economic drivers of land use and land cover change (LULCC) is necessary to ensure better informed sustainable forest management policy direction, strategy and practice to deliver C and livelihood options. Furthermore, our view suggests that considerations of the inherent spatial heterogeneity of the landscape and stand density are necessary to ensure development of accurate C estimation methodologies when developing C models. Notwithstanding, developing widely applicable biomass models for Southern Africa requires detailed assessments of including different aspects of wood C fractions.This review work is part of the ongoing PhD research project.The South African Forestry Company Limited (SAFCOL), the University of Pretoria and the African Forest Forum (AFF).http://www.tandfonline.com/loi/tsfs202018-02-28hb2017Plant Production and Soil Scienc

Community-centred approach for assessing social sustainability in mining regions : a case study of Chingola district, Zambia

DATA AVAILABILITY STATEMENT : The datasets generated for this study are available on request to the corresponding author.Social sustainability has received the least attention among the three-pillars of sustainable development in the mining regions of Africa. However, with the rapid population growth globally, social sustainability assessment using clearly defined indicators is becoming essential to ensuring urban sustainability, specifically in mining regions. This study assessed the contribution of the mining industry to the social sustainability of the Chingola district in terms of cumulative impacts and the extent to which CSR initiatives have contributed to a social sustainability profile. Mixed methods including in-depth key informant interviews guide and observation were used to collect data on social sustainability. The data were collected from 10 out of the 28 wards of Chingola, selected using a systematic random sampling. A total of 500 households of which 49 households (with a sampling unit of 10) and 10 key informants' stakeholders were purposively selected. Aggregation and normalization techniques were used to construct the composite indicators depicting the strength of each indicator. The social sustainability of the Chingola district based on the calculated composite indicators varies from weak-to-moderate sustainability. The proposed indicators could serve local government and mining companies, redirect development schemes, re-strategize the stakeholders' involvement, and support corporate governance.http://wileyonlinelibrary.com/journal/sdhj2023Plant Production and Soil Scienc

Land use/cover spatiotemporal dynamics, and implications on environmental and bioclimatic factors in Chingola district, Zambia

This study uses remote sensing and GIS techniques to examine the intensity and dynamics of land use/cover change and environmental indices across a four-decade period in the Chingola district of Zambia, from 1972 to 2020 using five classification stages (1972, 1992, 2001, 2013, and 2020). A total of 10 key climate change detection monitoring indices were generated using RClimDex to examine the implications of land degradation on the bioclimatic factors from 1983 to 2020. The findings revealed a significant expansion in Built-ups (7.3%/year), farmlands (3.18%/year), and mining areas (0.82%/year) at the expense of natural resources. The highest human pressure was exerted on Savannah woodlands (−0.78), through agriculture (0.76) and infrastructure development (0.44) between 1992 and 2001.The analysis of the bioclimatic indices revealed a significant decline in rainfall quantity and intensity, and a rising in temperature (warmer days and nights). The Annual rainfall has decreased by −3.25%, while the potential evapotranspiration has increased by 0.04% from 1983 to 2020, resulting in an Aridity Index of 0.60 and a moisture deficit index of −0.42. To offset agriculture’s propensity to spatially expand and further encroach into savannah woodlands and forests, urban containment policies and programs that stimulate agricultural intensification are needed to reduce urban sprawl and protect the city’s remaining forestlands.The World Bank financially supported this research through the African Centre of Excellence on Sustainable Mining (ACESM) Scholarship program of Copperbelt University.https://www.tandfonline.com/loi/tgnh20hj2023Plant Production and Soil Scienc

Local community perception of joint forest management and its implications for forest condition : the cast of Dambwa Forest Reserve in southern Zambia

This study conducted at Dambwa Forest Reserve in Livingstone, Zambia, evaluated the perception of local people about joint management of the forest reserve in the area and if there had been improvements to the livelihoods of the community and the ecological condition of the forest following joint forest management (JFM). Generally, more people (68%) participated in joint forestry management meetings than in forestry activities, such as forest patrol and prescribed early burning, and the size of the household significantly influenced the involvement of community members in JFM activities. The results also showed that the social status of the local community members played a significant role in their participation in JFM activities, with the forest committee member group being the most involved (57–61%). The perception of most members of the community was that there were neither monetary benefits derived from JFM nor any significant improvement in their livelihood following JFM. Although there were high regeneration levels (10 000 saplings ha−1) for all of the species, among the selected commercial trees Pterocarpus angolensis, Baikiaea plurijuga and Colophospermum mopane had natural regeneration consisting of 118, 72 and 67 saplings ha−1, respectively. Overall, 89% of the stems for the selected commercial species were less than 30 cm DBH, rendering them unsuitable for harvesting. It can be concluded that although the promotion of community involvement in forest protection and management contributes to regeneration of forest tree species, the communities did not perceive JFM as having improved their livelihood.The Ministry of Foreign Affairs of Finland through the Provincial Forestry Action Programme (PFAP II) and the Forest Department of Zambia.http://www.tandfonline.com/loi/tsfs2

Status of agrobiodiversity management and conservation in major agroecosystems of Southern Africa

This paper reviews the agroecosystems and agricultural biodiversity in Southern Africa and highlights the importance of the agricultural landscape in biodiversity conservation and the important role that the traditional farming systems play in conserving biodiversity. The review established that agrobiodiversity is of great importance to both small scale and large commercial farmers in Southern Africa through its provision of ecosystem services. The paper also highlights the significant loss of agrobiodiversity as a result of human population pressure and the transition from traditional mixed farming systems which is characterized with high agrobiodiversity, to modern monoculture farming resulting in decline of species diversity. Although concerted efforts are being made to promote the sustainable use and management of this agrobiodiversity, there need to have a multi-stakeholder approach so that conservation efforts are successful, a role that is currently played by the SADC Plant Genetic Resources Centre in Southern African conservation of agrobiodiversityhttp://www.elsevier.com/locate/age

Aboveground and belowground tree biomass and carbon stocks in the miombo woodlands of the Copperbelt in Zambia

Please read abstract in the article.The National Science and Technology Council (NSTC), African Forest Forum (AFF) and the University of Pretoria.https://www.tandfonline.com/loi/tcmt202022-06-14hj2022Plant Production and Soil Scienc

The application of UASs in forest management and monitoring : challenges and opportunities for use in the Miombo woodland

DATA AVAILABILITY STATEMENT : The data are available on request from the corresponding authorThe Miombo woodland is the most extensive tropical woodland in south-central Africa. However, field sample plot data on forest cover changes, species distribution and carbon stocks in the Miombo ecoregion are inadequate for effective forest management. Owing to logistical challenges that come with field-based inventory methods, remote sensing plays an important role in supplementing field methods to fill in data gaps. Traditional satellite and manned aircraft remote sensing platforms have their own advantages and limitations. The advent of unmanned aerial systems (UASs) has made it possible to acquire forest data at unprecedented spatial and temporal scales. UASs are adaptable to various forest applications in terms of providing flexibility in data acquisition with different sensors (RGB, multispectral, hyperspectral, thermal and light detection and ranging (lidar)) at a convenient time. To highlight possible applications in the Miombo woodlands, we first provide an overview of the Miombo woodlands and recent progress in remote sensing with small UASs. An overview of some potential forest applications was undertaken to identify key prospects and challenges for UAS applications in the Miombo region, which will provide expertise and guidance upon which future applications in the Miombo woodlands should be based. While much of the potential of using UASs for forest data acquisition in the Miombo woodlands remains to be realized, it is likely that the next few years will see such systems being used to provide data for an ever-increasing range of forest applications.The United States Agency for International Development through Partnerships for Enhanced Engagement in Research (PEER) program, Oliver R Tambo African Research Chair Initiative (ORTARChI) project, an initiative of Canada’s International Development Research Centre (IDRC), South Africa’s National Research Foundation (NRF) and the Department of Science and Innovation (DSI), in partnership with the Oliver & Adelaide Tambo Foundation (OATF) and National Science and Technology Council, Zambia.https://www.mdpi.com/journal/forestsam2023Forestry and Agricultural Biotechnology Institute (FABI)Plant Production and Soil Scienc