Mining activities contribute to an increase of specific metal contaminants in soils. This may adversely affect plant life and consequently impact on animal and human health. The objective of this study was to obtain the background metal concentrations in soils around the titanium mining in Kwale County for monitoring its environmental impacts. Forty samples were obtained with half from topsoils and the other from subsoils. X-ray fluorescence spectrometry was used to determine the metal content of the soil samples. High concentrations of Ti, Mn, Fe, and Zr were observed where Ti concentrations ranged from 0.47 to 2.8 %; Mn 0.02 to 3.1 %; Fe 0.89 to 3.1 %; and Zr 0.05 to 0.85 %. Using ratios of elemental concentrations in topsoil to subsoil method and enrichment factors concept, the metals were observed to be of geogenic origin with no anthropogenic input. The high concentrations of Mn and Fe may increase their concentration levels in the surrounding agricultural lands through deposition, thereby causing contamination on the land and the cultivated food crops. The latter can cause adverse human health effects. In addition, titanium mining will produce tailings containing low-level titanium concentrations, which will require proper disposal to avoid increasing titanium concentrations in the soils of the region since it has been observed to be phytotoxic to plants at high concentrations. The results of this study will serve as reference while monitoring the environmental impact by the titanium mining activities. © 2016, Springer-Verlag Berlin Heidelberg.
Tag: mining
Deforestation triggered by artisanal mining in eastern Democratic Republic of the Congo
The discovery of valuable minerals in the mineral-abundant eastern Democratic Republic of the Congo can stimulate extensive migration into remote areas of the Congo Basin rainforest. Despite the widespread practice of artisanal mining, its role in the ongoing deforestation has not received adequate attention. Using difference-in-differences estimation, we show that artisanal mining triggers deforestation at least 5 km from mining sites. Within this distance, the onset of mining causes an additional 4 percentage points of forest loss after 10 years. In total, the indirect deforestation caused by mining through the expansion of other land uses is 28 times larger than the forest area directly cleared for mining. Most of this loss is caused by increased farming around mines, followed by forest cleared for settlements. These indirect effects reveal a much larger role played by artisanal mining in deforestation dynamics than previously assumed and explain at least 6.6% of the total deforestation in the eastern Democratic Republic of the Congo.
The Effect of Biochar Amendment, Microbiome Inoculation, Crop Mixture and Planting Density on Post-Mining Restoration
Ecological restoration with a multispecies and multifunctional approach can accelerate the re-establishment of numerous ecosystem services. The challenges with land that is degraded, damaged, or destroyed post-mining are the low productivity of soil and the high potential for contaminants. Herein, we evaluated the multispecies and multifunctional approach to restoration strategy through a mixture of woody and herbaceous species, microsymbiont and biochar amendments, and plant spacing. The experiments were conducted using greenhouse and field trials located in Quebec, Canada. We used a mixture of tree species (Alnus viridis (Chaix) DC. ssp. crispa (Aiton) Turrill, Picea glauca (Moench) Voss, Populus tremuloides Michx. and Salix arbusculoides Andersson) and herbaceous species (Avena sativa L., Festuca rubra L. and Trifolium repens L.) on two types of gold-mine waste materials (fine tailing and waste rock). The biochar amendment and microbial inoculation were applied on both greenhouse and field trials. We found both positive and negative effects of plant spacing, biochar amendment and inoculation depending on their interactions. The net positive effect was shown by combining high plantation density, biochar, and inoculation factors on Alnus viridis ssp. crispa. Overall, plantation density was shown to be the most important factor in generating the net positive effect. We suggest that the mechanism was correlated with the improvement in microclimate through soil plant water conservation and microbial activity enhancement over soil temperature modification. Hence, we propose to put emphasis on microclimate improvement for accelerating the restoration processes, along with other combined factors, including microbial inoculation and biochar amendment.
Tree establishment on post-mining waste soils: species, density, and mixture effects
Tree establishment to restore degraded boreal post-mining lands is challenged by low soil productivity, a harsh microclimate, and potentially high contaminant levels. The use of mixed vegetation can facilitate the microclimate but increase competition for soil resources. A statistical accounting of plant–plant interactions and adaptation to multispecies conditions is hard to achieve in field experiments; trials under controlled conditions can distinguish effects of planting density and species interactions in the early stages of plant establishment. A greenhouse trial was established in containers (“mesocosms”) withwasterockorfine tailings from gold mines. Pregerminated (1-week-old) seedlings (Alnus viridis subsp. crispa, Picea glauca, Populus tremuloides, Salix arbusculoides) were planted using a Nelder density gradient design, modified for species combinations. A relative competition effect was estimated as a competitiveness index for each species combination, calculated as a ratio of a coefficients in the Holliday growth equation. The specific leaf area (SLA) was measured to indicate plant water stress adaptation. All species grew better in monoculture on fine tailings, while only P. tremuloides grew better in all mixtures on waste rock. Although net positive effects of density on SLA increment during early growth suggested microclimate improvement on fine tailings, no mixture provided advantages for both species in paired combinations. © 2021 The Author(s).
Restoring ex mining area using Pongamia pinnata in Central Kalimantan: a reclamation program alternative base on bioenergy species
Malapari (Pongamia pinnata (L) Pierre) is an endemic species of Leguminosae from southeast Asia, Australia and Afrika. Malapari is one species alternative of Reclamation Program in PT Asmin Bara Bronang. The aims of this study are to know the growth and adaptation rate of Malapari in extrime area after charcoal mining and to introduce the malapari for a alternative species for reclamation program with bioenergy potential species. The research method used is the census method in areas planted with malapari at PT ABB which was observed from 2020 with parameters including malapari growth; survival rate; analysis of soil fertility; biodiversity and carbon estimate. The results showed that malapari growth on post-mining land was very rapid where within 4 years it increased in height by an average of 184,92cm with a diameter growth of 10.76 cm and a survival rate of 87,78%, above ground biomass 584,04kg (274,5kg carbon) with very good leaf growth in fresh dark green The condition of early soil fertility becomes increased after planting. The great hope in this program is that malapari can be an alternative species for post-coal mining forest restoration from local superior species of use that has the potential to be a bioenergy source.
Searching priorities for a species at the brink of extinction: Threats analysis on the critically endangered Nubian Flapshell Turtle (Cyclanorbis elegans)
The Critically Endangered Nubian Flapshell Turtle (Cyclanorbis elegans) is found in the White Nile River system in South Sudan and northern Uganda. Over the past few decades, its populations have sharply declined, primarily due to human-induced threats, leading to its near-extinction across almost its entire range. In this paper, we present the results of a comprehensive threat analysis undertaken to pinpoint the challenges confronting the species within its natural habitat, specifically in the only known sites where it currently exists. We aimed to develop a conceptual framework to understand causal relationships among driving forces, threats and the target species. This framework allows the visualisation and analysis of the web of intricate interactions that contribute to the species’ decline and vulnerability. We convened a panel of experts who identified three primary direct threats to the Nubian Flapshell Turtle: (1) Sand mining (IUCN code 3.2); (2) Overfishing by native fishers and refugees (code 5.4) and (3) Habitat loss at nesting sites (code 7.3). Among these threats, overfishing had the largest geographical extension, the highest intensity and duration, while habitat loss occurred at the highest frequency. These threats varied significantly in intensity and frequency. Additionally, when assessing the overall magnitude of these threats, habitat loss and overfishing had the highest impact, with significantly higher scores compared to sand mining. Our experts also identified the underlying driving forces behind these threats: (1) Economic interests driving sand mining activities along the Nile; (2) The influence of civil conflict and refugee populations, which contribute to the demand for bushmeat; (3) the Chinese expatriates, that lead to overfishing; (4) The removal of bank vegetation serves as a catalyst for habitat loss at nesting sites. The resulting conceptual framework serves as a valuable tool for defining targeted conservation measures for each distinct threat.
Mining-sector dynamics in an era of resurgent resource nationalism: Changing relations between large-scale mining and artisanal and small-scale mining in Tanzania
Tanzania’s mining sector has long been dominated by two opposing scales of operations, large-scale mining (LSM), and artisanal and small-scale mining (ASM). From the mid-1990s, changing governments promoted LSM as a key sector for the restructuring of the economy through the generation of much needed foreign capital and increased fiscal earnings. However, a gradual shift in policies towards facilitating ASM, linked to the re-emergence of resource nationalism over the last two decades, can be observed. The paper analyses three types of dynamics that have the potential to improve the lot of ASM in Tanzania, namely increased efforts to enforce ASM rights, stronger support programmes, and the emergence of medium-scale miners (MSM) linked to global value-chains with the potential to bridge the gap between ASM and LSM and promote upgrading. Recent resource nationalist legislation also has the potential to promote more pro-ASM business models. This points to the increased political leverage of the ASM sector, which supports people in their millions, driven by electoral politics. However, from an ASM perspective the development is not unambiguous. Registration of rights to some extent remains ‘paper formalization’, the implementation of support programmes has slowed down, and MSM has so far been dominated by investors from emerging markets in partnership with local elites. Experience suggests that the continued emphasis on the redistribution of rights and revenues from foreign LSM may end up benefitting larger domestic business interests and state coffers more than ASM.
The new face of informality in the Tanzanian mineral economy: Transforming artisanal mining through foreign investment?
Artisanal and small-scale mining (ASM) has long been a mainstay of Tanzania’s rural economy, contributing to the livelihoods of more than three million Tanzanians. ASM is nonetheless yet to realise its full development potential, with the sub-sector continuing to be beset by social, environmental and economic underperformance issues as a result of structural resource and capacity constraints.
Like countries such as Ghana, Cameroon and Zimbabwe, foreign investors, often of Chinese origin, are increasingly participating in Tanzania’s ASM chains, which bring in much-needed capital, technologies and know-how. Such investments have the potential to contribute to resolving ASM barriers to upgrading, but could also pose a threat if not properly regulated.
This paper aims to offer new insights into the opportunities and risks associated with leveraging foreign private capital in support of ASM development. It does this by examining:
- The nature and scope of investor participation in Tanzania’s ASM,
- How (well) this participation is regulated, and
- The attendant sustainable and sector development implications.
Our analysis reveals how investor participation in Tanzania’s ASM sector has evolved in recent years and how such investments have contributed to fulfilling basic livelihoods needs of rural populations.
Upgrading Tanzania’s artisanal and small-scale mining through investor partnerships: Opportunities and challenges
Key messages
- Foreign investors are increasingly partnering with ASM operators to access mineral rights and reserves, in a high risk and high cost environment.
- This has led to an upgrading of ASM operations and indirect technology diffusion across mining areas through ‘demonstration effects’, but this upgrading may disrupt existing benefit sharing arrangements between ASM laborers and pit-owners/license holders.
- Upgrading of ASM, through capital infusion and technology advancement, is also accompanied by high environmental and occupational health and safety risks.
- The constrained capacity of sub-national institutions and lack of cross-institutional coordination are hampering governmental efforts to monitor and improve environmental and occupational health and safety practices of partnerships.
- Policy discussion is needed on the ASM-investor partnership model’s benefits and risks, and how best to harness its potential to upgrade the sector, as well as support the sustainable development of rural mining communities.
- Effective institutional coordination among key government institutions, particularly at sub-national level, is urgently needed to reduce the high environmental and labor safety risks posed by mechanized small-scale mines.