Gold and nickel mining are a common land use in the semiarid Eastern Goldfields region of Western Australia,, A frequent outcome of mining activity is highly saline landforms that result from the widespread use of hypersaline (> 50 g L(subscript)-1 NaCl) groundwater for mineral processing and hydraulic tailings reclamation, and from saline horizons in soils, subsoils and mullock. Under State government legislation, all mined land must be rehabilitated to a stable and sustainable landform at the completion of mining activities.There was little land rehabilitation carried out in the mining industry until the mid1980s. At that time, legislation was introduced and, in due course, guidelines were issued on recommended approaches to rehabilitation. Today, rehabilitation of disturbed areas is usually integrated into the mining program and has become the rule rather than the exception. There has, however, been limited innovation in recent years and the established methods are not suitable for every land rehabilitation scenario, especially those where very high salinity is an important factor. The aims of this thesis were to make a contribution towards a better understanding of the ecology of halophytes suitable for use in revegetation and the likely physical requirements for their sustainable establishment on post-mining landforms.In terms of germination, many of the halophytes currently used for rehabilitation of saline substrates are well suited in that they are able to germinate in solutions of up to 20 g L(subscript)-1 NaCl. Furthermore, when higher salinities are encountered, seed dormancy is induced until salinity is reduced to a level at which germination can occur. There were differences observed between germination of annual and perennial chenopods that reflected their successional roles where annual chenopods tend to have a higher salt tolerance and germinate more ++ / rapidly. I developed a tolerance index to enable different germination responses to be readily compared. Values for the tolerance index ranged from 5.7 to 25.3 for the halophytic species compared with a value of 0.2 for the glycophytic Secale cereale. Values for saltbushes (Atriplex) and bluebushes (Maireana) ranged from 6.5 to 9.8 while values for samphires (Halosarcia) were higher (10.7-17.4).Germination and early growth of taxa in the succulent genus, Halosarcia, were also studied. Though a member of the Chenopodiaceae, with a number of species occurring commonly throughout the region, Halosarcia spp. are not widely used in rehabilitation. This is in part attributable to the poor level of knowledge of germination and growth characteristics compared with saltbushes and bluebushes, many of which are widely used. Two species studied, H. halocnemoides subsp. halocnemoides and H. pruinosa, are more salt-tolerant for germination than some other chenopods more widely used. Furthermore, in terms of their early growth, each taxon continued to grow in salinities up to 40 g L(subscript)-1 NaCl, although root .Production and mass were reduced at that concentration. Another taxon, H. pergranulata subsp. pergranulata, was found to have a partial physical dormancy attributable to the testa, a phenomenon rare among halophytes. Dormancy was alleviated by scarification but was most effective where this occurred near the micropyle.Field trials were conducted to assess methods of rehabilitating severely salt-affected surfaces (EC(subscript)e > 50 dS m(subscript)-1). In the initial trial, a number of surface treatments, including ripping, rock mulching and mounding, were shown to reduce soil EC, in loam soils over a long period of time (seven years) compared with the control. In a subsequent trial, the use of good quality waste water, in conjunction with ponding banks, strongly ++ / promoted the establishment of vegetation by supplementing soil moisture and enhancing soil P although a reduction in soil EC(subscript)e was not observed. The depth and duration of ponding influenced the species that established and the cover achieved. Methods by which a soil cover could be established over hypersaline tailings surfaces were also investigated. The absence of a capillary break layer resulted in severe salinisation (EC(subscript)e > 100 dS m(subscript)-1) of a non-saline clay loam soil cover and likely severe difficulties in establishing and maintaining vegetation on the cover. Two types of capillary break layer, a synthetic membrane and a layer of coarse iron fayalite granules (nickel slag), were both effective at preventing the capillary rise of salts into the soil cover.The physical and biological characteristics of the shores of Lake Lefroy, a large salt lake in the Eastern Goldfields region, were analysed using multivariate techniques.Physical characteristics were strongly influenced by the orientation of the shore relation to the predominant winds, and by depth to the saline groundwater table. Plant species were distributed in zones across the lake shores with small changes in elevation resulting in substantial changes in species distributions. Those plant species occurring at the lowest elevations (Zone I), including Halosarcia spp., exhibited a very high tolerance of saline soil and groundwater through an ability to accumulate Na+ and Cl- and make the necessary osmotic adjustments, and a capacity to tolerance high groundwater levels. Under certain conditions, the lake shore environment could be a useful model for a rehabilitated landform.

The post-mining land use optimisation framework developed as part of this research underpins the need for examining site-specific decisions within the regional land planning context as well as in relation to the social, economic, and political perspectives within the mine’s localised planning domain. It emphasizes that the spatial and temporal planning and implementation of rehabilitation and land use-related activities remain continually changing throughout the mining life cycle. This implies that amendments, refinements or corrective action should be an integral aspect of this planning, improving the trajectory towards success as new site knowledge and learnings becomes available. Rehabilitation activities should be implemented as soon as site disturbance (construction) starts and maintained throughout the operational and decommissioning periods. More importantly, these activities remain even more pertinent to the monitoring and maintenance period, during which successful implementation of the pre-defined land use/s can be demonstrated. Rehabilitation-, land use and mine closure plans are hence ‘living’, changing tools, aligned towards a common goal – defining a resilient post-mining landscape that will, ultimately, enable harnessing the altered landscapes’ new characteristics to optimise services to post-mining communities that either provides similar resourcing needs from the land, or alternative resources that contribute to the long-term viability of the area. / Dissertation (MSc) - University of Pretoria, 2018. / Coaltech Research Institute, Chamber of Mines / Chamber of Mines / Geography, Geoinformatics and Meteorology / MSc / Unrestricted

We describe a case study evaluating the ecological impact of Bromus tectorum L. (cheatgrass) invasion following fire disturbance and the effectiveness of revegetation in improving ecological integrity in a degraded semi-arid shrub steppe system. The effectiveness of rehabilitation efforts was assessed from measurements of arthropod richness, vegetation and arthropod community composition, and ground cover characteristics in three habitats: undisturbed, burned and weed-infested (B. tectorum), and burned and rehabilitated with native and non-native vegetation. Arthropods were collected in each habitat using pitfall traps. Differences in arthropod richness were compared using rarefaction curves. Non-metric multidimensional scaling, and non-parametric multivariate statistical procedures including analysis of similarity and similarity percentages routines were used to compare arthropod and vegetation community composition and ground cover characteristics between habitats. Arthropod communities in the rehabilitated habitat were distinct from and intermediate to those observed in the undisturbed and weed-infested habitats. Rehabilitation in this instance resulted in an improvement in ecological integrity and perhaps an intermediate step on the way complete restoration. Arthropod richness, arthropod and vegetation community composition, and ground cover characteristics were all useful indicators of ecological integrity, but returned slightly different results. Assessing multiple variables yielded the most complete understanding of the habitats studied.

Open cut coal mining in the Bowen Basin of central Queensland had disturbed in excess of 55,000 ha by the turn of the 21st century and 72,000 ha by 2006. Strong export demand in recent years (since approximately 2000) has led to greater production from existing mines and to a proliferation of new ones. Therefore, over the ensuing decades, the level of mining activity can be expected to increase substantially the areas of erstwhile agricultural land that are disturbed. As mines exhaust their resources, companies will be obliged to achieve acceptable end uses for the various domains at those sites. The possibility of having successfully rehabilitated domains at selected sites certified on a progressive basis holds some appeal. While all stakeholder groups find a return of the land to its prior use (extensive cattle-grazing) an appealing goal, mining companies walk a tight-rope. The legislation under which the early mines were established does not bind them as tightly to the environmentally friendly outcomes as applies to new mines. Nonetheless, recent legislative trends as well as companies’ own policies, encourage them to exceed society’s environmental expectations. Regardless of the end use that is designated, relinquishment is permitted only subject to a satisfactory assessment of the risks to its sustainability. Cattle-grazing is considered as a suitable end use, partly because the return of mined land to its prior use is preferred to its designation to some other use and partly because cattle could serve to reduce the bulk of pasture growth that occurs at some sites, reducing the risk of erosion if an intense fire were to occur followed by heavy rain. Graziers’ primary motivation for seeking tenure of mined land is financial. Factors that determine both a site’s productivity and its commercial ‘worthwhileness’ are examined in this research. The major focus of this research however, is the style of management that the custodial grazier may employ. Since any future custodian is likely to be a local landholder (perhaps the grazier family from whom the land was originally acquired for mining some decades earlier), it is the management style of local farmers that is of primary interest. Some graziers use the land more intensively than others: some with more sensitivity than others. Since the reconstructed landscape is inherently more fragile than undisturbed land, differences in management style could be critical to the sustainability of grazing. Factors driving, or at least being associated with, farmers’ land management decisions were identified from prior research as draft components of a risk assessment model for grazing. A survey of the characteristics and circumstances of Bowen Basin graziers was then conducted with a view to modelling their influence on graziers’ land management style. The survey ascertained the prior probabilities among the target graziers of the elements being modelled. An estimate of the role of these factors in shaping land management decisions was then obtained by eliciting the opinions of industry experts. These processes allowed development of a predictive model that estimates the likelihood of conservative and sensitive land management under various scenarios of site characteristics and grazier-based factors. Output from the model showed that the capital circumstances of a grazier’s business have an influence over the predicted management style of 25% of the difference between best-case and worst-case scenarios. There is a 17% greater likelihood of low-risk grazing where a grazier strongly wants tenure of the land for reasons that go beyond financial gain. The grazier’s underlying values and attitudes to land management account for a further 14%, followed by the operational structure of the business (12%), and the external climatic and economic environment (9%). Interventions that mining companies could implement to increase the likelihood of low-risk management has an influence of 23%. The credibility of the model’s output was evaluated by reference to real-life experiences of graziers who have managed cattle on mined land and their miner counterparts. Consistency of opinion among the consulted experts also contributed to the confidence that can be placed in the model’s findings. The model identifies the sources of risk if currently available mined land is used for grazing. It improves understanding of the situation in a holistic manner, and predicts the likelihood of low-risk grazing management under scenarios of interest to the user. The model identifies actions that mining companies could take to reduce risks associated with graziers’ management style. The model may also guide future rehabilitation work by highlighting features of rehabilitation that would make them more suited to commercially feasible and low-risk cattle production – or by purposefully and transparently planning for cattle-grazing not to be the designated end use.

Made available in DSpace on 2016-08-19T18:20:35Z (GMT). No. of bitstreams: 1 Jane Karina Silva Mendonca.pdf: 3318033 bytes, checksum: c9b49c1165461842ca1fd7f1454ae286 (MD5) Previous issue date: 2006-11-27 / FUNDAÇÃO DE AMPARO À PESQUISA E AO DESENVOLVIMENTO CIENTIFICO E TECNOLÓGICO DO MARANHÃO / This study regards the sustainable development of the types of palms from Protection Environment Area (APA) in Baixada Maranhense, in the handcraft production of geotextile that has been used in the rehabilitation of some degraded areas by erosion and helps to involve the local poor community, as well as those people who work with handcraft and extraction activities of those plants. It has been carried out bibliography and cartography surveys, questionnaires that were filled, in order to assess the extraction and production of mats and tests of the effectiveness of the geotextile, through an experimental station. The species selected: babaçu, buriti, carnauba, and tucum, are appropriate to this new way of use, observing the limits that those plants and their environment demand, to have an activity that has the goal of the social economic environmental sustainability. / O estudo aborda o uso sustentável de espécies de palmeiras da APA da Baixada Maranhense, na produção artesanal de geotêxteis utilizadas na recuperação de áreas degradadas por erosão, propondo o envolvimento de comunidades carentes das áreas degradadas, bem como daquelas que trabalham com atividades artesanais e extrativistas com essas plantas. Foram realizados levantamentos bibliográficos e cartográficos, elaboração e aplicação de formulários para avaliação da extração e produção das telas e testes de eficiência das geotêxteis, através de uma estação experimental. As espécies selecionadas: babaçu, buriti, carnaúba e tucum, cujas características são favoráveis a essa nova categoria de uso, desde que respeitados os limites impostos, pela planta e seu ambiente, para que se tenha uma atividade que vise a sustentabilidade sócio-ambiental e econômica.

Submitted by Franciele Moreira (francielemoreyra@gmail.com) on 2017-08-24T18:27:50Z No. of bitstreams: 2 Dissertação - Diógenes Aires de Melo - 2017.pdf: 29280291 bytes, checksum: 54f60896fed20376341146bea3a59ed5 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-09-15T12:49:02Z (GMT) No. of bitstreams: 2 Dissertação - Diógenes Aires de Melo - 2017.pdf: 29280291 bytes, checksum: 54f60896fed20376341146bea3a59ed5 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-09-15T12:49:02Z (GMT). No. of bitstreams: 2 Dissertação - Diógenes Aires de Melo - 2017.pdf: 29280291 bytes, checksum: 54f60896fed20376341146bea3a59ed5 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-06-26 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / One of the biggest concerns with municipal solid wastes (MSW) is the risk of degradation of final disposal areas (FDA), since many landfills installed as sanitaries, in Goiás State, Brazil, returned to the condition of ilegal dump sites (MP-GO, 2012), and because the technical standards don´t adopt the newest concept of environmental geotechnics (JUCÁ, 2003). It´s necessary evaluate the FDA of MSW and establish the prioritization criterias for the rehabilitation in order to decide about their future. The research aimed the proposition of a multicriteria decision process for the rehabilitation of FDA of MSW in the Metropolitan Region of Goiânia (MRG). The MRG, composed by 20 municipalities, was choosen because it´s responsible for the generation of 46.85 % of the total of 4,088.23 tonnes/day of MSW of Goias State (SECIMA, 2014b). Three evaluations were carried out in 20 areas: quality evaluation of final disposal, through Landfill Quality Index (LQI) (FARIA, 2002); evaluation of environmental vulnerability, with the elaboration of synthesis map, integrating Topograpic Wetness Index (TWI), Length Slope (LS), Water Table and Soils; and the evaluation of legal restriction of the area uses according with Resolution No 5/2014 of Environmental State Council. The evaluations showed only 4 FDA of Aparecida de Goiânia, Bela Vista de Goiás, Trindade and Senador Canedo Counties obtained LQI greater than 8.01 and they were considered as a sanitary landfills. Most areas has moderate vulnerability and the other areas range between low and very low. Only 4 areas are free of legal restriction of use: Inhumas, Bonfinópolis, Bela Vista de Goiás and Hidrolândia; 2 are subject to agreement: Santo Antônio de Goiás and Brazabrantes; and the other 14 are restricted areas. From the hierarchical structure of the 3 combined and weighted evaluation criteria for each of the 20 alternative-areas, the Analytic Hierarchy Process (AHP) was performed, which ordered Guapo as the most priority and lastly, Hydrolandia County. The decision about the future of each area indicates in ascending order that the following 14 FDA: Guapó, Caldazinha, Nova Veneza, Caturaí, Nerópolis, Aparecida de Goiânia, Trindade, Senador Canedo, Goianira, Goianápolis, Terezópolis de Goiás, Aragoiânia, Abadia de Goiás e Goiânia, should to be closed and recovered. On the other hand, the FDA´s of Santo Antônio de Goiás, Brazabrantes, Inhumas, Bonfinópolis and Hidrolândia may continue to dispose their wastes since the elaboration and approval of sanitary landfill projects, as determined by the respective Environmental Agency. The FDA of Bela Vista de Goiás will be able to continue as a sanitary landfill. Finally, possible scenarios were indicated for the final disposal future of the MSW of MRG by sending preferably to the 4 shared landfills pointed by the Solid Waste State Plan, private landfill or manual trench landfill for counties with the generation less than 10 tonnes/day, together with the search of new solutions for final destination. It was concluded that not all landfill considered sanitary can continue its activities due to the environmental fragility of the area and non-compliance with the restrictions imposed by the legislation. / Uma das grandes preocupações com os resíduos sólidos urbanos (RSU) é o risco de degradação das áreas de disposição final (ADF), visto que muitos aterros instalados como sanitários, em Goiás, voltaram à condição de lixão (MP-GO, 2012) e porque as normas técnicas não adotam os conceitos mais recentes de geotecnia ambiental (JUCÁ, 2003). É preciso avaliar as ADF de RSU e estabelecer os critérios de priorização para reabilitação a fim de se decidir acerca do futuro das mesmas. A pesquisa objetivou a proposição de um processo decisório multicriterial para a reabilitação de áreas de disposição final de RSU na Região Metropolitana de Goiânia (RMG). A RMG, composta por 20 municípios, foi escolhida por ser responsável pela geração de 46,85 % do total de 4.088,23 t/dia de RSU de Goiás (SECIMA, 2014b). Foram realizadas 3 avaliações nas 20 áreas: avaliação da qualidade da disposição final, por meio do Índice de Qualidade de Aterros (IQA) (FARIA, 2002); avaliação da vulnerabilidade ambiental, com aelaboração de mapa síntese integrando os fatores Topographic Wetness Index (TWI) e Length Slope (LS), a profundidade do lençol freático e o mapa de solos; e a avaliação da restrição legal de uso das áreas conforme Resolução No 5/2014 do Conselho Estadual do Meio Ambiente. As avaliações mostraram que apenas as 4 ADF, de Aparecida de Goiânia, Bela Vista de Goiás, Trindade e Senador Canedo, obtiveram IQA maiores que 8,01 e foram consideradas como aterros sanitários. A maioria das áreas possuem moderada vulnerabilidade e as demais variam de muito baixa a baixa. Somente 4 estão livres de restrição legal: Inhumas, Bonfinópolis, Bela Vista de Goiás e Hidrolândia; 2 estão sujeitas à anuência: Santo Antônio de Goiás e Brazabrantes; e as 14 restantes são áreas restritas. A partir da estruturação hieráquica dos 3 critérios de avaliação combinados e ponderados sobre cada uma das 20 áreas-alternativas, foi procedida a Análise Hierárquica de Processos (AHP) a qual ordenou Guapó como a mais prioritária e por último Hidrolândia. A decisão do futuro de cada área indicou em ordem crescente que 14 ADF: Guapó, Caldazinha, Nova Veneza, Caturaí, Nerópolis, Aparecida de Goiânia, Trindade, Senador Canedo, Goianira, Goianápolis, Terezópolis de Goiás, Aragoiânia, Abadia de Goiás e Goiânia, devem ser encerradas e recuperadas. Já as ADF de Santo Antônio de Goiás, Brazabrantes, Inhumas, Bonfinópolis e Hidrolândia poderão continuar dispondo resíduos desde que elaborados e aprovados projetos de adequação em aterros sanitários conforme determinações do respectivo Órgão Ambiental. Já a ADF de Bela Vista de Goiás poderá continuar como aterro sanitário. Por fim, foram indicados cenários possíveis para a disposição final futura dos RSU da RMG por meio de envio preferencial a 4 aterros compartilhados apontados pelo Plano Estadual de Resíduos Sólidos, aterro privado ou instalação de aterros por vala para municípios com geração menor que 10 t/dia, juntamente com a busca de novas soluções de destinação final. Concluiu-se que nem toda ADF considerada aterro sanitário, pode continuar suas atividades devido à fragilidade ambiental da área e ao não atendimento das restrições impostas pela legislação.