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Modelagem sistêmica do ciclo de vida do aguapé no Pantanal e anãlise do uso desta biomassa para a produção de bio-óleo e bio-fertilizante / System modeling of water hyacinth life cycle in Pantanal and analysis of the use of this biomass for bio-oil and bio-fertilizer productionBuller, Luz Selene, 1970- 02 October 2012 (has links)
Orientadores: Enrique Ortega Rodriguez, Ivan Bergier Tavares de Lima / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-19T11:57:30Z (GMT). No. of bitstreams: 1
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Previous issue date: 2012 / Resumo: O Pantanal ocupa uma área extensa do Brasil em torno de 140.000 km²; seus ecossistemas são caracterizados por áreas com alagamento periódico, campos inundados constantemente e ambientes aquáticos naturais com lagoas (baías), rios e canais (vazantes e corixos); não existem quedas d¿ água para a geração de energia elétrica dentro da bacia. Em virtude das áreas alagadas existem poucas vias para o abastecimento de combustíveis para as fazendas produtoras que, assim, dependem fortemente de diesel e lenha como fonte de energia. Além disso, as cidades da região dependem da energia elétrica originária de outros estados da federação e a produção industrial (cimento e ferro gusa) é baseada em carvão vegetal, cuja origem é questionável, possivelmente do desmatamento do Cerrado. O uso de fontes alternativas de biomassa produzidas localmente poderia amenizar a carência energética no Pantanal. O aguapé, que se desloca nas lagoas e rios do Pantanal na forma de ilhas flutuantes, pode ser uma fonte alternativa de biomassa para a obtenção de combustíveis sólidos, líquidos e gasosos renováveis produzidos e distribuídos localmente. Esta pesquisa objetivou uma análise do ciclo de vida do aguapé na região de Corumbá mediante estudos teóricos que permitiram modelar e simular a dinâmica de crescimento (nas baías e margens dos rios) e de decaimento do aguapé (decomposição), elaborar cenários de colheita sustentável e dos mecanismos de remoção de nutrientes pelo aguapé em diferentes épocas do ano e realizar a avaliação emergética da produção natural de biomassa e de produtos derivados da conversão termoquímica desta biomassa, bio-óleo e bio-carvão. O estudo foi complementado com uma avaliação econômica de uma unidade industrial de pirólise rápida de biomassa. Os resultados obtidos permitem que tomadores de decisão avaliem de modo sistêmico a viabilidade ambiental e econômica da criação de um sistema para extração e aproveitamento de biomassa de aguapé. Os níveis de colheita estudados e os indicadores emergéticos e econômicos apontam para a viabilidade ecológica e econômica de um sistema operando com extração de 1% da biomassa de aguapé escoada no rio Paraguai. Para níveis maiores de extração, os resultados trazem à tona questões que requerem estudos adicionais a fim de garantir uma visão ecológica sobre a exploração de recursos naturais do Pantanal que é um importante provedor de serviços ambientais. As interferências na região devem ser baseadas em mecanismos de monitoramento contínuo dos impactos ambientais e socioeconômicos da atividade antrópica e em premissas de responsabilidade socioambiental no longo prazo / Abstract: Pantanal covers an extensive area of Brazil, around 140.000 km²; its ecosystems are characterized by periodic flooded areas, permanently flooded fields and natural aquatic environments with bays, rivers, streams and channels (locally denominated ¿vazantes¿ and ¿corixos¿); there are no water falls for power generation within the basin. Because of the flooded areas there are few routes for fuel supply to farms that rely heavily on diesel fuel as an energy source. In addition, the cities of the region depend on the energy originated in other states of the federation and its industrial production (cement and cast iron) is based on charcoal, whose origin is questionable, possibly from the deforestation of the Cerrado (Brazilian Savanna). The use of alternative sources based on biomass locally produced could ease energy shortages in the Pantanal. Water hyacinth, which flows in the lakes and rivers of Pantanal in the form of floating islands, can be an alternative source of biomass to obtain solid, liquid and gaseous renewable fuels locally produced and distributed. This research aimed the analysis of water hyacinth life cycle in Corumbá by theoretical studies that allowed to model and to simulate the growth dynamics (in the bays and riverbanks) and water hyacinth decay (decomposition), to elaborate scenarios of sustainable harvesting level and mechanisms of nutrient removal by water hyacinth at different periods of the year and to perform the emergy evaluation of the natural production of biomass and of the industrial products derived from the thermochemical conversion of biomass, bio-oil and biocharcoal. The study was complemented with an economic evaluation of one plant of biomass fast pyrolysis. The results allow decision makers to systemically evaluate the environmental and economic feasibility of a system for extraction and utilization of water hyacinth biomass. Harvest levels studied and emergy and economic indicators obtained indicate the ecological and economic feasibility of an operating system with extraction of 1% of the water hyacinth biomass that flows in Paraguay River. For higher levels of extraction, the results bring to light issues that require further investigation to ensure an ecological view of the exploitation of natural resources of Pantanal that is a leading provider of environmental services. The interference in the region should be based on mechanisms for continuous monitoring of environmental and socioeconomic impacts of human activity and on premises of social and environmental responsibility in the long term / Mestrado / Engenharia de Alimentos / Mestre em Engenharia de Alimentos
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The effect of temperature on the feeding and development of Neochetina eichhorniae weevil larvae on water hyacinth (Eichhornia crassipes)Bokotomba, Ndongo Fyfy January 2017 (has links)
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, in partial fulfilment of the requirements for the degree of Master of Science. Johannesburg, March 2017. / Water hyacinth (Eichhornia crassipes) is an example of an alien invasive plant, threatening ecosystems around the world. Taking into consideration all the negative impacts caused by the proliferation of water hyacinth, many control measures have been implemented to manage this weed. These include mechanical control, chemical control and biological control. But in recent years, the focus has shifted towards natural enemies for control (biological control) of water hyacinth because they have many advantages for environmental safety. However, in South Africa, success is limited in most parts of the country. Factors affecting the success of biological control of water hyacinth in South Africa have been attributed in part to weather conditions. Therefore, further studies and other strategies are needed to reinforce the biological control of water hyacinth. This is why this research investigated the influences of temperature on Neochetina eichhorniae larvae feeding and development on water hyacinth, to contribute to the future management of water hyacinth biological control.
To measure the effect of temperature on the feeding and development of Neochetina eichhorniae larva, experiments were conducted at four fixed temperatures (15 °C, 20 °C, 25 °C, and 30 °C). Larval feeding is expected to be greater and the development faster at warm temperatures compared with cold temperatures. The results of this study confirmed that, both feeding and larval development increased with an increase in temperature. The highest larval feeding damage was recorded at 30°C and the lowest at 15°C. Similar to the feeding of larvae, warmer temperatures were more favourable to the growth of larvae than cold temperatures; all larvae found at 30°C were in their third instars (with 0.72 mm being the biggest headwidth found) while all larvae at 15°C were in the first instars (with 0.28 mm being the smallest headwidth found).
Even if the optimal temperature for larval performance took place at 30 °C (with a high amount of biomass removal), it was at 25 °C that the larvae had a larger effect on the growth of water hyacinth. Larval feeding damage reduced the growth of water hyacinth by 30 % at 25 °C and only affected 24 % of water hyacinth growth at
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30 °C. Therefore, for the biocontrol of water hyacinth, the ideal temperature to slow the progression of the weed will be recommended at between 25- 30 °C. / LG2017
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Study on treatment of domestic wastewater of an area in Tu Liem district, Hanoi, by water hyacinth / Nghiên cứu xử lý nước thải sinh hoạt tại một khu dân cư thuộc quận Từ Liêm, Hà Nội, bằng Bèo lục bìnhPham, Khanh Huy, Nguyen, Pham Hong Lien 09 December 2015 (has links) (PDF)
Domestic wastewater is one of the most interested environmental issues in Vietnam, especially in big cities and suburban residential areas. Most of the wastewater was not treated in the right way before discharging to environment. In this research, the author used water hyacinth as a main aquatic plant in aquatic pond model to treat wastewater. The experiment was operated continuously in 1 year with hydraulic retention time (HRT) is 11 and 18 days. Hydraulic loading rate (HRL) is 300 and 500 m3/ha/day, respectively. Treatment efficiency of the model for TSS is 90% (remaining 6 -12mg/l); COD, BOD5 is 63 - 81% (remaining 10 - 48mg/l); TP is 48 – 50% (remaining 3.5 - 9.8mg/l); TKN is 63 - 75% (remaining 8 - 17mg/l). Polluted parameters in effluent were lower than A and B levels of Vietnam standard QCVN 14: 2008/BTNMT and QCVN 40: 2011/BTNMT. The doubling time of water hyacinth in summer is 18days, and in autumn and winter is 28.5 days. Experiment results showed that we can use water hyacinth in aquatic pond to treat domestic wastewater with medium scale. We can apply this natural treatment method for residential areas by utilizing existing natural ponds and abandoned agricultural land with capacity up to 500m3/ha day. However, to get better efficiency we should combine with other aquatic plant species to treat wastewater and improve environmental landscape. / Nước thải – xử lý nước thải sinh hoạt hiện đang là một trong những vấn đề môi trường được quan tâm tại Việt Nam nhất là tại các thành phố lớn và các khu dân cư. Hầu hết lượng nước thải chưa được xử lý đúng cách trước khi thải ra môi trường. Trong nghiên cứu này, tác giả sử dụng mô hình hồ thủy sinh và sử dụng cây Bèo lục bình để xử lý nước thải sinh hoạt của một khu dân thuộc huyện Từ Liêm, tại khu vực này nước thải bị thải trực tiếp vào sông Nhuệ. Thực nghiệm đã được tiến hành trong khoảng thời gian một năm, trải qua các mùa của khu vực miền Bắc với hai chế độ vận hành HRT là 18 và 11 ngày, tương ứng với tải trọng thủy lực HRL là 300 và 500 m3/ha/ngày. Kết quả cho thấy mô hình thủy sinh sử dụng cây bèo lục bình cho kết quả tốt, hiệu suất xử lý với các chất ô nhiễm đạt được như sau: chất rắn lơ lửng đạt 90%, COD, BOD5 đạt 63 - 81%, Phốt pho tổng giảm tới 48 -50%, Nitơ tổng giảm tới 63 - 75%. Hàm lượng các chất ô nhiễm trong nước thải đầu ra của mô hình đều thấp hơn ngưỡng A và B của các tiêu chuẩn QCVN 14: 2008/BTNMT và QCVN 40: 2011/BTNMT. Bên cạnh đó tác giả cũng đã xác định định được tốc độ sinh trưởng của cây bèo tại khu vực miền Bắc là 18 ngày vào mùa hè và 28.5 ngày vào mùa thu đông. Kết quả nghiên cứu cho thấy có thể sử dụng bèo lục bình để xử lý nước thải sinh hoạt, với qui mô vừa và nhỏ và nên áp dụng cho các khu vực ven đô, nông thôn nơi có diện tích đất rộng hoặc tại các hồ sinh thái của các khu đô thị. Tuy nhiên, để hiệu quả tốt hơn ta cần kết hợp với nhiều loại thực vật thủy sinh khác để ngoài tác dụng xử lý nước thải mà còn tạo cảnh quan môi trường xung quanh.
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How elephants utilize a miombo-wetland ecosystem in Ugalla landscape, Western TanzaniaKalumanga, Elikana January 2015 (has links)
African elephants are ‘keystone’ species with respect to biodiversity conservation in Africa since they maintain habitats that support several animal communities by changing vegetation structure through foraging and by dispersing seeds between landscapes. Elephants are also ‘flagship’ species because, given their impressive size, they can make people sympathetic and stimulate local and international concerns for their protection. Economically, elephants contribute to national revenues as tourists are willing to pay to watch them. Despite all these factors, little is known however about elephant movement and how they utilize resources, especially in miombo-wetland ecosystems. This thesis investigates how elephants utilize resources in a miombo-wetland ecosystem in the Ugalla landscape of Western Tanzania over different protected areas containing different resource users. Using Global Positioning System (GPS) collars fitted to six elephants, it was observed that some elephant families are not confined in one protected area in the Ugalla landscape. Rather, they moved readily between different protected areas. Elephant movements were restricted to areas near the rivers, especially the Ugalla River, during the dry season and were dispersed widely during the wet season. As they move, elephants in the miombo woodlands of Ugalla selected the most abundant woody plants for browsing. Common to many woody plants, the browsed plants were short of mineral nutrients (e.g., sodium, calcium). Elephants obtained additional minerals by eating soils from certain termite mounds. Soils from termite mounds are richer in mineral elements (e.g., sodium, calcium, iron) compared to soils from the surrounding flood plain or compared to the browsed plants. However, the recorded termite mounds from which elephants eat soils were not evenly distributed in the landscape but confined mainly to the flood plains in the Ugalla Game Reserve. The Ugalla River, which is the main source of water for the elephants and other animals and also supports fishing activities by the local people in Ugalla during the dry seasons, is infested by the water hyacinth (Eichhornia crassipes). Such infestation potentially limits access to these precious surface water supplies. In addition at the regional level, the Ugalla River is among the major rivers that flow into the Lake Tanganyika which is shared by the countries of Tanzania, Burundi, Democratic Republic of Congo and Zambia. Thus, the spread of water hyacinth if left unchecked threatens to impact Lake Tanganyika, affecting many countries and ecosystem services. This thesis highlights that sustainable conservation of biodiversity in different protected areas in the Ugalla landscape requires an integrated management approach that will embrace conservation of different interrelated landscape resources required by both wildlife and the rural poor populations for their livelihoods. Regular coordinated wildlife anti-poaching patrols should be initiated across the entire Ugalla landscape because the elephants, among other wildlife, utilize different protected areas in Ugalla. Local communities should also be engaged in conservation initiatives (e.g., controlling the spread of the water hyacinth) as these directly impact local livelihoods. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Manuscript. Paper 2: Manuscript. Paper 3: Manuscript. Paper 4: Manuscript.</p> / INTEGRATED NATURAL RESOURCES MANAGEMENT
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Evaluation of a plant-herbivore system in determining potential efficacy of a candidate biological control agent, cornops aquaticum for water hyacinth, eichhornia crassipesBownes, Angela January 2009 (has links)
Water hyacinth, Eichhornia crassipes Mart. Solms-Laubach (Pontederiaceae), a freefloating aquatic macrophyte of Neotropical origin, was introduced into South Africa as an ornamental aquarium plant in the early 1900’s. By the 1970’s it had reached pest proportions in dams and rivers around the country. Due to the sustainability, cost efficiency and low environmental risk associated with biological control, this has been a widely used method in an attempt to reduce infestations to below the threshold where they cause economic and ecological damage. To date, five arthropod and one pathogen biocontrol agents have been introduced for the control of water hyacinth but their impact has been variable. It is believed that their efficacy is hampered by the presence of highly eutrophic systems in South Africa in which plant growth is prolific and the negative effects of herbivory are therefore mitigated. It is for these reasons that new, potentially more damaging biocontrol agents are being considered for release. The water hyacinth grasshopper, Cornops aquaticum Brüner (Orthoptera: Acrididae), which is native to South America and Mexico, was brought into quarantine in Pretoria, South Africa in 1995. Although the grasshopper was identified as one of the most damaging insects associated with water hyacinth in its native range, it has not been considered as a biocontrol agent for water hyacinth anywhere else in the world. After extensive host-range testing which revealed it to be safe for release, a release permit for this candidate agent was issued in 2007. However, host specificity testing is no longer considered to be the only important component of pre-release screening of candidate biocontrol agents. Investigating biological and ecological aspects of the plant-herbivore system that will assist in determination of potential establishment, efficacy and the ability to build up good populations in the recipient environment are some of the important factors. This thesis is a pre-release evaluation of C. aquaticum to determine whether it is sufficiently damaging to water hyacinth to warrant its release. It investigated interactions between the grasshopper and water hyacinth under a range of nutrient conditions found in South African water bodies as well as the impact of the grasshopper on the competitive performance of water hyacinth. Both plant growth rates and the response of water hyacinth to herbivory by the grasshopper were influenced by nutrient availability to the plants. The ability of water hyacinth to compensate for loss of tissue through herbivory was greater under eutrophic nutrient conditions. However, a negative linear relationship was found between grasshopper biomass and water hyacinth performance parameters such as biomass accumulation and leaf production, even under eutrophic conditions. Water hyacinth’s compensatory ability in terms of its potential to mitigate to detrimental effects of insect feeding was dependent on the amount of damage caused by herbivory by the grasshopper. Plant biomass and the competitive ability of water hyacinth in relation to another freefloating aquatic weed species were reduced by C. aquaticum under eutrophic nutrient conditions, in a short space of time. It was also found that grasshopper feeding and characteristics related to their population dynamics such as fecundity and survival were significantly influenced by water nutrient availability and that environmental nutrient availability will influence the control potential of this species should it be released in South Africa. Cornops aquaticum shows promise as a biocontrol agent for water hyacinth but additional factors that were not investigated in this study such as compatibility with the South African climate and the current water hyacinth biocontrol agents need to be combined with these data to make a decision on its release. Possible management options for this species if it is to be introduced into South Africa are discussed.
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A spatial and temporal analysis of the changes in alien macrophyte communities and a baseline assessment of the macroinvertebrates associated with Eurasian watermilfoil, Myriophyllum spicatum L. (Haloragaceae) in the Vaal RiverFordham, Colin Justin January 2012 (has links)
The majority of South Africa’s fresh water (lotic and lentic), is eutrophic and this has resulted in water hyacinth, Eichhornia crassipes (C.Mart.) Solms. (Pontederiaceae) becoming South Africa’s most damaging aquatic macrophyte. Recently however, concerns have also been voiced over the presence of highly invasive submerged macrophyte species, such as Eurasian water-milfoil, Myriophyllum spicatum L. (Haloragaceae) in the Vaal River. Interaction studies between floating and submerged macrophytes have shown that floating macrophyte dominance restricts light penetration into the water column shading out submerged macrophytes while submerged macrophyte dominance reduces nutrient availability in the water column limiting floating macrophyte growth. This cycle ensures that these species cannot coexist in the same habitat for extended periods of time. The aims of this thesis were to: 1. Investigate changes in the historical and current macrophyte dominance in the Vaal River 2. Determine whether these changes could be attributed to stochastic events, such as floods and herbicide control measures. 3. The physio-chemical conditions of the water column, and whether pressure from herbivory by macroinvertebrates had possibly influenced Eurasian water-milfoil’s ability to dominate. Spatial and temporal analysis of satellite imagery revealed that water hyacinth and submerged macrophyte species dominated different regions of the study area over different periods of time from 2006 to 2010. This was significantly correlated with nitrate concentrations of the water column. One of the lower Vaal River Water Management Areas (WMA) had changed from a water hyacinth dominated state in 2006 to an alternative submerged macrophyte dominated stable state in 2008. It was concluded that this change could be attributed to: a stochastic flooding event in 2006; perturbation from integrated control measures implemented against water hyacinth; and low nitrate concentrations of the WMA. The lack of any substantial macroinvertebrate herbivory pressure or control measures implemented against Eurasian water-milfoil, compared to similar surveys conducted in the U.S.A. and its native range in Eurasia was shown to contribute to its dominance. Future successful integrated control programmes, including biological control against Eurasian water-milfoil, could provide the perturbation required to restore the ecosystem. However, without the reduction in nitrate concentration levels, water hyacinth will remain the dominant stable state of the rest of the Vaal River.
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Uso de cinza de olaria e composto orgânico de macrófita aquática na recuperação de solos degradados / Use of pottery ash and organic compound of aquatic macrophyte in degraded soil recoveryGaudêncio, Hiara Ruth da Silva Câmara 25 February 2016 (has links)
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Previous issue date: 2016-02-25 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The intensification of human activity for economic purposes has caused environmental impacts increasingly significant, for example, the suppression of vegetation and as a result soil impoverishment. In this sense, this research aimed to evaluate the use of pottery ash and organic macrophyte compound in the recovery of degraded soils. Thus, the experiment was conducted in a greenhouse with experimental design in a factorial arrangement of 5x5, being five doses of the compound of water hyacinth and five doses of ash with three replications, where the volume of soil corresponded to 2 dm³ and ash doses corresponded to 0, 1, 3, 5 and 10% of the volume of each vessel and the water hyacinth compound at 0, 5, 10, 20 and 30%. After mixing the composition of soil, compound and gray equivalent to each treatment, these were placed in plastic vessels, incubated for 20 days and then held the transplanting of Jucá seedlings (Libidibia ferrea). On the occasion of collection, the plants were cut at ground level, dry in forced-air oven at 70° C to constant weight, weighed, crushed in a grinder to obtain the dry matter of shoot (MSPA) and they were subsequently mineralized by nitric digestion. In the extracts were determined the total content of Fe, Zn, Mn, Cu, Cd and Pb. After removal of the plants, the soil in each vessel was air dried, homogenised and a sample was removed for performing analysis of Fe, Zn, Mn, Cu, Cd and Pb. The addition of ash and compound doses contributed to the increase in pH, which consequently influenced the absorption of heavy metals by plants as well as in their growth / A intensificação da atividade humana para fins econômicos tem ocasionado impactos ambientais cada vez mais significativos, como por exemplo, a supressão vegetal e por consequência o empobrecimento do solo. Nesse sentido, esta pesquisa teve como objetivo avaliar o uso de cinza de olaria e composto orgânico de macrófita aquática na recuperação de solos degradados. Assim, o experimento foi conduzido em casa de vegetação com delineamento experimental em esquema fatorial 5x5, sendo cinco doses do composto de aguapé e cinco doses de cinza com três repetições, onde o volume de solo correspondeu a 2 dm³ e as doses de cinza corresponderam à 0, 1, 3, 5 e 10% do volume de cada vaso e às de composto de aguapé à 0, 5, 10, 20 e 30%. Após a mistura da composição solo, composto e cinza equivalente a cada tratamento, esta foi colocada em vasos plásticos, incubados 20 dias e em seguida realizado o transplantio das mudas de Jucá (Libidibia ferrea). Por ocasião da coleta, as mudas foram cortadas ao nível do solo, secas em estufa de circulação forçada de ar a 70°C até peso constante, pesadas, trituradas em moinho para obtenção da matéria seca da parte aérea (MSPA) e posteriormente foram mineralizadas por digestão nítrica. Nos extratos foram determinados os teores totais de Fe, Zn, Mn, Cu, Cd e Pb. Após a retirada das mudas, o solo de cada vaso foi seco ao ar, homogeneizado e quantificado os teores de Fe, Zn, Mn, Cu, Cd e Pb. A adição das doses de cinza e o composto contribuíram para o aumento do pH, que consequentemente influenciou na absorção dos metais pesados pelas mudas, bem como no crescimento das mesmas / 2017-01-16
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Aquatic invasions of the Nseleni River system: causes, consequences and controlJones, Roy William January 2015 (has links)
Globalization has seen an unprecedented dispersal of exotic and alien species worldwide resulting in worldwide homogenization and sometimes extinction of indigenous or endemic taxa. When an exotic species becomes established in a new habitat the invasive organisms are capable of having an impact on indigenous community dynamics and the overall structure and function of ecosystems. Furthermore, the impact of invasion is determined by the geographical range, abundance and the per-capita or per-biomass effect of the invader. However, the success of the introduced organisms is reliant on their ability to acclimate to the physiochemical conditions of the newly invaded environment.Freshwater ecosystems are especially vulnerable to invasions because there are numerous potential routes of introduction including intentional pathways such as stocking, and unintentional pathways such as the release of ballast water and aquarium releases. Efforts to limit the introduction of invasive species or to manage established exotic populations are often hindered by insufficient understanding of the natural history of problematic species. Relatively little is known regarding the physiological tolerances of many taxa. Knowledge about specific species ecophysiological constraints allows for the prediction of future patterns of invasion more accurately, including where an introduced organism would probably survive, thrive and disperse. Furthermore, data on the physiological tolerances of an introduced exotic organism may provide data necessary for effective management and control. This studyinvestigated three invasive species in the Nseleni River system in a protected area in KwaZulu-Natal. The species studied were, Tarebia granifera (Quilted melania – Lamarck, 1822), Pterygoplichthys disjunctivus (Suckermouth armoured catfish - Weber, 1991) and Eichhornia crassipes (water hyacinth – (Martius) Solms-Laubach,). The Nseleni River flows into Lake Nsezi which is responsible for providing potable water to the surrounding towns and industry, as well as the surrounding rural communities. The Enseleni Nature reserve has become the centre for biodiversity dispersal in the immediate area, due to the change in landscape surrounding the protected area.An important step in developing alien invasive species management strategies in protected areas is determining their extent and invasive traits. Tarebia granifera is a prosobranch gastropod originally from South-East Asia that has become invasive in several countries around the world including South Africa. Snail populations were sampled at nine sites throughout the Nseleni/Mposa river system every six weeks over a twelve month period. The snail was abundant throughout the system, especially in shallow waters of less than 1m in depth.The first positive identification the loricariid catfish Pterygoplichthys disjunctivus for the Nseleni River was in 2006. The original introduction is believed to have been via the aquarium trade. The aim of the study was to assess the usefulness of the unified framework with regard to management of fish invasions by assessing the invasion stage of the loricariid population and identifying appropriate management actions using the Blackburn et al. (2011) framework. The fish were sampled at nine different sites and three different depths over a period of twelve months, as well as when two ichthyological surveys were carried out on the Nseleni River system. This invasive fish has been located throughout the system and both male and female fish were collected. The smallest fish sampled was a fingerling of a day or two old and the smallest pregnant female was a mere 270mm TL. This is a clear indication that this fish is breeding in the river system.Although T. granifera and P. disjunctivus were abundant in the Nseleni/Mposa river system, it was not clear what their role in the system was, and in particular if they were competing with any of the indigenous species. Therefore, isotope samples were collected from numerous taxa over a two week period, with the exception of Pterygoplichthys disjunctivus samples, which were collected over 12 months. The δ13C and δ15N signatures of all samples were determined. The niche overlap between the invasive and indigenous snails was effectively zero (1.02E-13%), indicating no shared food resources. The medium ranges of dNRb (7.14) and dCRb (9.07) for the invasive fish indicate that it utilizes a wider range of food resources and trophic levels than the majority of indigenous fish. A medium CDb value (2.34) for the invasive fish species, P. disjunctivus, describes medium trophic diversity, with three indigenous species possessing higher diversity and three possessing lower diversity. Furtherresults indicated that there was no direct dietary competition between P. disjunctivus and indigenous species. Eichhornia crassipes was first recorded on the Nseleni River in 1978, and has been shown to have a significant negative impact on the biodiversity of the Nseleni/Mposa River system and therefore required a control intervention. Although biological control using the two weevil species Neochetina eichhornia (Warner) and N. bruchi (Hustache) has been credited with affecting a good level of control, the lack of a manipulated post-release evaluation experiments has undermined this statement. Five experimental plots of water hyacinth of 20m2 were sprayed with an insecticide to control weevils. After ten months the plants in the sprayed plots were significantly bigger and heavier than those in the control plots that had natural populations of the biological control agents. This study has shown unequivocally that biological control has contributed significantly to the control of water hyacinth on the Nseleni/Mposa River system.The management plan for the Enseleni Nature Reserve identifies the need to control invasive and/or exotic organisms within the boundary of the protected area. In addition, set guidelines have been implemented on how to control these organisms, so that indigenous organisms are least affected. Lack of control of exotic organisms can have serious consequences for indigenous species. It is therefore of utmost importance that the population dynamics of the invading organism be understood, what the potential impact could be and how to control them. Furthermore, it has also acknowledged the threat of possible exotic species invasions from outside of the protected area that might result in threats to the protected area and that these must be investigated, researched and managed.This thesis has identified Tarebia granifera, Pterygoplichthys disjunctivus and Eichhornia crassipes as being a threat to indigenous biodiversity within the protected area, as well as in adjacent areas to the protected area. The thesis will therefore investigate the hypothesis that both Tarebia granifera and Pterygoplichthys disjunctivus are having a direct negative effect on available food resources for indigenous species of organisms. In addition, this thesis will investigate if theNeochetina species that have previously been introduced onto E. crassipes are having any negative effect on this invasive alien aquatic plant.
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Avaliação do uso de sistemas de wetlands construídas no tratamento de esgotos sanitários / Evaluation of use of constructed wetlands in the sanitary sewage treatmentMello, Débora de 24 February 2016 (has links)
CAPES / Neste trabalho foi avaliado o comportamento de diferentes configurações de sistemas de wetlands construídas na remoção de matéria carbonácea, nitrogenada e fosforada de esgotos sanitários. Foram construídos três sistemas de tratamento em caixas retangulares de polipropileno com 55 cm de largura, 95 cm de comprimento e 58 cm de altura (cada), com volume útil de 0,10 m3. Os sistemas foram operados com tempos de detenção hidráulica (TDH) de 24 h, 48 h e 72 h e mantidos a temperatura ambiente. Estes foram classificados como sistema de wetlands construída (SWC 1) preenchida com areia, brita e mudas da macrófita aquática (Eichhornia crassipes), sistema de wetlands construída (SWC 2) preenchido com areia e brita (controle) e sistema de lâmina livre (SLL) com mudas da macrófita no esgoto sanitário. A caracterização físico-química dos materiais filtrantes foi realizada com determinação do pH, massa específica aparente, densidade relativa, teor de umidade, teor de cinzas e granulometria. Os parâmetros pH, temperatura do líquido, demanda química de oxigênio (DQO), fósforo total, nitrogênio total Kjeldahl (NTK), nitrogênio amoniacal, nitrito, nitrato, sólidos totais e suspensos totais foram determinados em amostras do afluente e efluente de cada sistema. Na análise do crescimento e da composição das macrófitas foram aferidos o comprimento e a largura de cada indivíduo e determinado os teores de fósforo e nitrogênio total no tecido vegetal. Para determinação de sólidos totais e totais voláteis no biofilme formado nos materiais filtrantes foram coletadas amostras de brita e areia dos sistemas. Análises da biomassa da macrófita para incorporação em blocos de concreto foram também realizadas. Na caracterização dos materiais suporte foi observado que os mesmos estão de acordo com os recomendados para este tipo de tratamento. O afluente utilizado na alimentação dos SWCs foi caracterizado como esgoto sanitário e classificado como fraco para DQO e SST e médio para ST. As melhores eficiências de remoção para fósforo, nitrogênio amoniacal e NTK foram obtidos no SLL com 38% (TDH de 72 h), 35% (TDH de 48 h) e 47% (TDH de 72 h), respectivamente. Para DQO a melhor eficiência de remoção foi verificada no SWC 2 com 80% no TDH de 48 h. Os resultados de absorção de NTK e fósforo total pela Eichhornia crassipes, mostraram que as macrófitas possuem capacidade de absorção destes nutrientes. Na absorção de fósforo, o SLL apresentou maior porcentagem de incorporação pela planta de 1,56% no TDH de 72 h (135° dia), coincidindo com o TDH de melhor eficiência de remoção obtida na análise físico-química de 38%. O melhor resultado da porcentagem de incorporação da fibra vegetal da macrófita em blocos de concreto foi de 2%. / The behavior of different configurations of constructed wetlands was evaluated in the removal of carbonaceous, nitrogenous and phosphorous matter of sanitary sewage. There treatment systems were set up in rectangular box of polypropylene with 55 cm of width, 95 cm of length and 58 cm of height (each) with total volume of 0.10 m3. The systems were operated with hydraulic retention time (HRT) of 24 h, 48 h and 72h and kept at room temperature. These were classified as constructed wetlands system (CWS 1) filled with sand, gravel and seedlings of aquatic macrophyte (Eichhornia crassipes), constructed wetlands system (CWS 2) filled with sand and gravel (control) and free-water-surface (FWS) with macrophyte seedlings in the sanitary sewage. The physical-chemical characterization of the support materials was carried out with determination of pH, bulk density, relative density, moisture content, ash content and particle size. The parameters pH, liquid temperature, chemical oxygen demand (COD), total phosphorus, total Kjeldahl nitrogen (TKN), ammonia nitrogen, nitrite, nitrate, total and total suspended solids were measured in samples of the influent and effluent of each system. In the macrophyte growth and composition survey, the length and width of each individual were measured and phosphorus and total nitrogen in the plant tissue were determined. Samples of gravel and sand were collect from the systems to determine the concentrations of total and total volatile solids in the biofilm formed in the support materials. Analysis of macrophyte biomass for incorporation into concrete blocks were also performed. In the characterization of supported materials it was observed that the same are consistent with recommended for this type of treatment. The affluent used in feeding the SWCs was characterized as sewage and classified as weak to COD and TSS and medium to ST. The best efficiency for phosphorus, ammonia nitrogen and NTK was obtained in 38% SLL (HRT of 72 hours), 35% (HDT of 48 h) and 47% (HDT 72h), respectively. To the best COD removal efficiency was observed in the SWC 2 to 80% in the HDT 48 h. The results NTK absorption and total phosphorus by Eichhornia crassipes, macrophytes have shown that absorptive capacity of these nutrients. In phosphorus absorption, the SLL had a higher percentage of incorporation by 1.56% in the plant TDH 72 h (135 th day), coinciding with the TDH best removal efficiency obtained in the physical and chemical analysis of 38%. The best result of the percentage of incorporation of vegetable fiber macrophyte in concrete blocks was 2%.
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Micorrização e crescimento do pinhão manso sob solo degradado tratado com hidrorretentor associado à materiais orgânico /Santos, Adriana Avelino. January 2010 (has links)
Orientador: Ana Maria Rodrigues Cassiolato / Banca: Luiz Antonio Graciolli / Banca: Gilberto Colodro / Resumo: O solo é um meio que engloba diferentes substâncias químicas e colóides e uma alta diversidade biológica. Estes componentes apresentam íntima relação funcional para sustentabilidade dos ecossistemas e, sua degradação, geralmente causada pela ação antrópica, acarreta um grande prejuízos ambientais e socioeconômicos para as gerações atuais e um enorme risco para as gerações futuras. Para reverter um processo como este, são necessárias intervenções por meio de estratégias como a revegetação. O objetivo do trabalho foi avaliar crescimento e colonização micorrízica do pinhão manso em solo decaptado que recebeu inoculo de fungos micorrizicos arbusculares, hidrogel e materiais orgânicos. O experimento foi conduzido de maio de 2008 a maio 2009, na Fazenda de Ensino, Pesquisa e Extensão (FEPE) da UNESP - Universidade Estadual Paulista, Campus de Ilha Solteira, no município de Selvíria-MS. O delineamento experimental foi o em blocos casualizado, em esquema fatorial 4x2x2, ou seja, 3 tratamentos com material orgânico (aguapé, composto e aguapé+composto), 2 tratamentos com hidrogel (com e sem adição) e 2 tratamentos de inoculação (com e sem inoculação) empregando solo proveniente de uma área preservada de cerrado como fonte de microrganimos, incluíndo fungos micorrízicos arbusculares, com 4 repetições e 5 plantas por tratamentos. O composto foi preparado com materiais de poda e esterco de bovino. Avaliou-se: o crescimento das plantas em 7 épocas diferentes, a caracterização química e número de esporos em 4 épocas, além da porcentagem de colonização micorrízica, presença de flores, número de ramos e de folhas e peso fresco e seco da parte aérea. O tratamento com hidrogel não mostrou interferência no crescimento de plantas, mas, assim como o solo-inóculo, aumentou a esporulação, a colonização micorrízica e a produção de matéria seca... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The soil is a medium that contain different chemical substances and colloids and a high biological diversity. These components have functional relationship on the sustainability of ecosystems and their degradation, usually caused by human action, which causes great socio-economic damage to the present generations and an enormous risk for the future generations. To reverse such process, action is needed using strategies, such as, revegetation. The objective of this study was to evaluate the growth and mycorrhiza colonization of Jatropha on decapitated soil that received organic materials and hydrogel. The experiment was conducted from May 2008 to May 2009, the Farm Education, Research and Extension (FEPE), UNESP - Univ. Estadual Paulista, Ilha Solteira Campus, located at Selvíria city-MS, Brazil. The experimental design was randomized blocks in factorial scheme 3x2x2, i.e., 3 treatments with organic materials (water hyacinth, compost and water hyacinth + compost), 2 hydrogel treatments (with and without addition) and 2 inoculations treatments (with and without inoculation) using natural soil from a preserved 'cerrado' area as a source of microorganisms, including mycorrhizal fungi, with 4 replications and 5 plants per each. The compound was prepared with materials pruning and cow dung. The growth of plants in 7 different times, the chemical characterization and number of spores in 4 times, and the percentage of mycorrhizal colonization, presence of flowers, branches and leaves and fresh and dry weight of air part was evaluated. Treatment with hydrogel showed no interference with the growth of plants; however, as well as the soilinoculum, they increased sporulation, root colonization and production of dry matter. The organic materials treatments positively altered the condition of the ground, plant growth, mycorrhizal colonization and sporulation; the improved performances... (Complete abstract click electronic access below) / Mestre
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