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Mapping grass nutrient phosphorus (P) and sodium (NA) across different grass communities using Sentinel-2 dataMashamba, Tendani January 2017 (has links)
A research report submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirement for the degree of Master of Science (Environmental Sciences) at the School of Geography, Archaeology & Environmental Studies
March 2017 / Accurate estimates and mapping of grass quality is important for effective rangeland management. The purpose of this research was to map different grass species as well as nutrient Phosphorus (P) and Sodium (Na) concentration across grass communities using Sentinel-2 imagery in Telperion game reserve.
The main objectives of the study were to: map the most common grass communities at the Telperion game reserve using Sentinel-2 imagery using artificial neural network (ANN) classifier and to evaluate the use of Sentinel-2 (MSI) in quantifying grass phosphorus and sodium concentration across different grass communities. Grass phosphorus and sodium concentrations were estimated using Random Forest (RF) regression algorithm, normalized difference vegetation index (NDVI) and the simple ratios (SR) which were calculated from all two possible band combination of Sentinel-2 data.
Results obtained demonstrated woody vegetation as the dominant vegetation and Aristida congesta as the most common grass species. The overall classification accuracy = 81%; kappa =0.78 and error rate=0.18 was achieved using the ANN classifier. Regression model for leaf phosphorus concentration prediction both NDVI and SR data sets yielded similar results (R2 =0.363; RMSE=0.017%) and (R2 =0.36 2; RMSE=0.0174%). Regression model for leaf sodium using NDVI and SR data sets yielded dissimilar results (R2 =0.23; RMSE=16.74 mg/kg) and (R2 =0.15; RMSE =34.08 mg/kg). The overall outcomes of this study demonstrate the capability of Sentinel 2 imagery in mapping vegetation quality (phosphorus and sodium) and quantity.
The study recommends the mapping of grass communities and both phosphorus and sodium concentrations across different seasons to fully understand the distribution of different species across the game reserve as well as variations in foliar concentration of the elements. Such information will guide the reserve managers on resource use and conservation strategies to implement within the reserve. Furthermore, the information will enable conservation managers to understand wildlife distribution and feeding patterns. This will allow integration of effective conservation strategies into decisions on stocking capacity. / MT 2017
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Estimation of nitrogen content across grass communities at Telperion Nature Reserve using Sentinel-2Chabalala, Yingisani Winny January 2017 (has links)
A thesis report submitted in partial fulfilment of the requirements for the degree in Master of Science in GIS and Remote Sensing
Faculty of Science
University of the Witwatersrand.
March 2017
Johannesburg, South Africa / Grass nitrogen is the main indicator of forage conditions in a rangeland environment. The main objectives of the research were to map the quality and quantity of common grass communities and to predict Nitrogen (N) content across different grass communities. A machine-learning algorithm of Support Vector Machines (SVM) was tested in the mapping of grass quality and quantity. An overall accuracy of 72.68% was achieved for the mapping analysis which demonstrated the capability of the Sentinel-2 10m resolution in discriminating the spectral properties of different grass communities.
The foliar nitrogen was predicted using univariate regression, stepwise multiple linear regression (SMLR), multivariable regression methods, partial least square regression (PLSR) and random forest (RF). Foliar N was predicted using multivariate regression models; the best model was selected based on the highest coefficient of determination (R2) value, and the low root mean square error (RMSE). The best RF model for foliar N estimation was based on the simple ratio (SR) index because the model attained the highest prediction accuracy of 35%. The study demonstrates the applicability of Sentinel-2 MSI utility in mapping and estimation of leaf N at a landscape scale .The results of both regression models (univariate and multivariate) such as random forest and partial least squares indicated that the inclusion of the Sentinel-2 MSI red edge bands provides an opportunity to accurately map and estimate leaf bio-chemical composition using remote sensing techniques. / MT 2017
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Foraging behaviour of ruminant and non-ruminant grazers as a function of habitat heterogeneity in Telperion and Ezemvelo Nature Reserves(Ezemvelo section)Hamunyela, Ndamonenghenda January 2017 (has links)
A research report submitted to the Faculty of Science, University of the
Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the
degree of Master of Science in Resource Conservation Biology. Johannesburg, 29 May 2017. / An understanding of animal foraging behaviour is key to proper management
strategies that ensure the survival and species persistence within nature
reserves. Here the foraging behaviour of ruminant (hartebeest and wildebeest)
and non-ruminant (zebra) grazers were observed and compared between two
areas with distinctively different vegetation structure, the natural vegetation
(NL) and previously cultivated land (PCL), in Telperion and Ezemvelo Nature
Reserves (TENR). Natural vegetation was dominated by tall grass of low
greenness with patches of short to very short grass, while the PCL was
dominated by areas of very short to short grass (grazing lawns) with patches of
medium to tall grass. Step rate (SR) and foraging time spent per feeding station
(FTFS) were used as indices of foraging behaviour. I also measured the
characteristics of the grass sward (grass height and greenness) grazed on by the
three species. Both ruminants had high SR and low FTFS. Despite having similar
SR and FTFS, ruminants grazed on grass of different height. Hartebeest preferred
tall grass with low greenness content (0-10%), while wildebeest preferred short
to very short grass and were significantly selective of areas with relative high
greenness (11-50%) on PCL, more so than any other species. Compared to
ruminant grazers the non-ruminant (zebra) had low SR and high FTFS and like
hartebeest they grazed on medium to tall grass of very low greenness content (0
10%). This study did not reveal any difference in feeding behaviour within
species between the two study sites. The finding of this study confirms that
ruminant and non-ruminant species have different foraging behaviour, and
habitat heterogeneity is necessary for the reserve to support different grazing
species.
Key words: digestive physiology, feeding station, step rate, wildebeest,
hartebeest, zebra / GR2018
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Almejando o mundo do futuro: a proposição de um modelo prospectivo global para produção e consumo sustentável de carne bovina / Aiming at the future: proposing a global prospective model for the sustainable production and consumption of bovine meatOrnellas, Regina da Silva 27 April 2017 (has links)
Com a população mundial prevista para chegar a 9 bilhões de pessoas durante o século 21, ocorre também o aumento na demanda de carne bovina, que segue acompanhado de aumento no consumo de recursos naturais do planeta. Entre os impactos causados pelo aumento da demanda está uma atmosfera que se aquece pelas emissões de gases do efeito estufa. Em vista disso, a busca de eficiência tecnológica no uso de recursos torna-se um alvo, porém tratado de forma secundária pelo segmento. Considerando as possibilidades atuais e futuras da produção e consumo global de carne bovina, quatro cenários prospectivos podem surgir para 2040, os quais envolvem a tecnologia de diferentes formas. Logo, essa pesquisa respondeu a pergunta: Quais cenários plausíveis de produção e consumo global sustentável de carne bovina podem ser projetados para 2040? Para responder a essa pergunta e atingir os objetivos de pesquisa, foi desenvolvida uma inédita metodologia, composta por quatro distintas fases. Como fator preponderante para a resposta de pesquisa, foi desenvolvido um modelo prospectivo, o qual identifica um padrão global sustentável de produção e consumo de carne bovina para 2040. Através do modelo, foram desenvolvidos quatro cenários prospectivos para a produção e consumo global da pecuária bovina de corte: um cenário que contempla a atual produção, consumo e tecnologia; três cenários que incluem avanços tecnológicos, projeção de demanda, população e Pib per capita. Através do modelo e de seus respectivos cenários, foi possível analisar que há embora hajam diferentes níveis de produção e consumo global, é possível buscar de forma efetiva a sustentabilidade global mediante a mudança de eficiência no uso de recursos naturais, avanços tecnológicos e a implementação de políticas públicas de produção. Através da pesquisa também foi possível perceber que a aplicação de técnicas de cenários prospectivos são de suma importância para avanços acadêmicos e a tomada de decisão de gestores. / The world population is expected to reach 9 billion people during the 21st century; therefore, there is an increase in the demand for bovine meat, which is accompanied by an increase in the consumption of natural resources of the planet. Among the impacts caused by this rising demand is an atmosphere that is heating up by greenhouse gas emissions. In view of this, the search for technological efficiency in the use of resources becomes a target, but it is treated in a secondary way by the segment. Therefore, this research answered the question: What plausible scenarios of sustainable global bovine meat production and consumption can be projected for 2040? To answer this question and achieve the research objectives, an unprecedented methodology was developed, composed of four distinct phases. As a preponderant factor for the research response, a prospective model was developed, which identifies a sustainable global pattern of beef production and consumption by 2040. Through the model, four prospective scenarios were developed for the global production and consumption of bovine livestock Of cut: a scenario that contemplates the current production, consumption and technology; Three scenarios that include technological advances, projection of demand, population and GDP per capita. Through the model and their respective scenarios, it was possible to analyze that although there are different levels of global production and consumption, it is possible to effectively seek global sustainability through a change in efficiency in the use of natural resources, technological advances and the implementation of Public production policies. The research also made possible to notice that the application of techniques of prospective scenarios are of paramount importance for academic advances and the decision making of managers.
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Almejando o mundo do futuro: a proposição de um modelo prospectivo global para produção e consumo sustentável de carne bovina / Aiming at the future: proposing a global prospective model for the sustainable production and consumption of bovine meatRegina da Silva Ornellas 27 April 2017 (has links)
Com a população mundial prevista para chegar a 9 bilhões de pessoas durante o século 21, ocorre também o aumento na demanda de carne bovina, que segue acompanhado de aumento no consumo de recursos naturais do planeta. Entre os impactos causados pelo aumento da demanda está uma atmosfera que se aquece pelas emissões de gases do efeito estufa. Em vista disso, a busca de eficiência tecnológica no uso de recursos torna-se um alvo, porém tratado de forma secundária pelo segmento. Considerando as possibilidades atuais e futuras da produção e consumo global de carne bovina, quatro cenários prospectivos podem surgir para 2040, os quais envolvem a tecnologia de diferentes formas. Logo, essa pesquisa respondeu a pergunta: Quais cenários plausíveis de produção e consumo global sustentável de carne bovina podem ser projetados para 2040? Para responder a essa pergunta e atingir os objetivos de pesquisa, foi desenvolvida uma inédita metodologia, composta por quatro distintas fases. Como fator preponderante para a resposta de pesquisa, foi desenvolvido um modelo prospectivo, o qual identifica um padrão global sustentável de produção e consumo de carne bovina para 2040. Através do modelo, foram desenvolvidos quatro cenários prospectivos para a produção e consumo global da pecuária bovina de corte: um cenário que contempla a atual produção, consumo e tecnologia; três cenários que incluem avanços tecnológicos, projeção de demanda, população e Pib per capita. Através do modelo e de seus respectivos cenários, foi possível analisar que há embora hajam diferentes níveis de produção e consumo global, é possível buscar de forma efetiva a sustentabilidade global mediante a mudança de eficiência no uso de recursos naturais, avanços tecnológicos e a implementação de políticas públicas de produção. Através da pesquisa também foi possível perceber que a aplicação de técnicas de cenários prospectivos são de suma importância para avanços acadêmicos e a tomada de decisão de gestores. / The world population is expected to reach 9 billion people during the 21st century; therefore, there is an increase in the demand for bovine meat, which is accompanied by an increase in the consumption of natural resources of the planet. Among the impacts caused by this rising demand is an atmosphere that is heating up by greenhouse gas emissions. In view of this, the search for technological efficiency in the use of resources becomes a target, but it is treated in a secondary way by the segment. Therefore, this research answered the question: What plausible scenarios of sustainable global bovine meat production and consumption can be projected for 2040? To answer this question and achieve the research objectives, an unprecedented methodology was developed, composed of four distinct phases. As a preponderant factor for the research response, a prospective model was developed, which identifies a sustainable global pattern of beef production and consumption by 2040. Through the model, four prospective scenarios were developed for the global production and consumption of bovine livestock Of cut: a scenario that contemplates the current production, consumption and technology; Three scenarios that include technological advances, projection of demand, population and GDP per capita. Through the model and their respective scenarios, it was possible to analyze that although there are different levels of global production and consumption, it is possible to effectively seek global sustainability through a change in efficiency in the use of natural resources, technological advances and the implementation of Public production policies. The research also made possible to notice that the application of techniques of prospective scenarios are of paramount importance for academic advances and the decision making of managers.
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Impact on climate change and adaptation on cattle and sheep farming in the Eastern Cape Province of South AfricaMandleni, Busisiwe January 2011 (has links)
This study focused on the impact of climate change and adaptation on small-scale cattle and sheep
farming in the Eastern Cape province of South Africa. Using information from 500 livestock farmers
between 2005 and 2009 farming season, three methods of analysis were used to determine impacts of
climate change and adaptation. They were Principal Component Analysis (PCA), Binary Logistic
Regression Model (BLRM) and Heckman Probit Model (HPM). Findings revealed that cattle
production decreased during the study period 2005 to 2009. Preliminary descriptive statistics results
indicated that farmers had different perceptions on climate change and adaptation measures between
the periods 2005 and 2009. Further analysis using PCA showed that the different perceptions could
be grouped into: (i) drought and windy weather patterns; (ii) information and adaptation; (iii) climate
change extension services; (iv) intensive cattle and sheep production; and (v) temperatures. The
results of the BLRM indicated that the most significant factors that affected climate change and
adaptation were: (i) non-farm income per annum; (ii) type of weather perceived from 2005 to 2009;
(iii) livestock production and ownership; (iv) distance to weather stations; (v) distance to input
markets; (vi) adaptation strategies and (vii) annual average temperature. From the HPM the results
indicated that marital status, level of education, formal extension, temperatures and the way in which
land was acquired, significantly affected awareness on climate change. Variables that significantly
affected adaptation selections were gender, formal extension, information received on climate
change, temperatures and the way in which land was acquired.It was concluded that in the area of study, change in climate was already perceived by small-scale
cattle and sheep farmers. Households that perceived differences in seasonal temperatures during the
survey period were less likely to adapt to climate change. Having access to extension services
increased the likelihood of adaptation to climate change. Information on climate change to improve
livestock production appeared to play a significant role in the selection of adaptation measures. The
recommendation was that government should consider cattle and sheep farmers’ perceptions on
climate change when deciding on programmes for cattle and sheep production. It further suggested
that the most significant factors that affected climate change, adaptation, and awareness and
adaptation selections be considered when adaptation programmes are planned. / Agriculture Animal Health and Human Ecology / D.Phil. (Environmental Management)
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Assessment of environmental-livestock interactions in crop-livestock systems of central Ethiopian highlandsNigatu Alemayehu Minase 09 1900 (has links)
The study was done in Adaa district which is one of the 12 districts in East Shoa zone in Oromia regional state of Ethiopia. It is located southeast of Addis Ababa at 38o51’ 43.63’’ to 39o04’ 58.59’’ E and 8o46’ 16.20’’ to 8o59’ 16.38’’ N, on the western margin of the Great East African Rift Valley. The altitude ranges from 1 500 to ≥ 2 000 meters above sea level. The district has a high potential for mixed livestock and crop production systems. The purpose of this study was to make up for the paucity of information on livestock and environment interaction by assessing the relationship of livestock, soil, water, land, climate and crops under mixed crop-livestock production systems in central Ethiopian highlands.
The objectives of the study were: (a) to assess the effect of change in land management on carbon storage and the contribution of livestock to carbon storage; (b) to examine the impact of livestock on natural resources and the environment; (c) to assess the effects of the change in traditional agricultural practices, expansion of factories, slaughter houses, greenhouses and flower farms on water and soil quality; (d) to evaluate the effect of climate change on livestock production under small-scale agriculture; and (e) to recommend options for mitigation and adaptation to environmental changes.
The research design was non-experimental and did not involve the manipulation of the situation, circumstances or experiences of the interviewees. The design was comparative research that compared two or more groups on one or more variables, such as the effect of agricultural land use management, tillage type etc. on carbon storage in the soil. This research also applied a longitudinal design that examined variables such as the performance exhibited by groups over time. Purposive sampling was often used to measure the effect of agricultural, industrial effluent and human interferences on the environment by measuring nutrient contents at sources in the soil, water and manure. Biological data were complemented by key socio-economic survey by interviewing individual farmers and focus groups from sampling sites. Secondary data were also reviewed to measure soil degradation and run-off attributed to livestock.
Results showed that animal waste and farmyard manure had the highest contribution in the addition of carbon in the soil. This implied that for most of carbon inputs livestock products and by-products had a greater place in the carbon sink. Therefore, livestock production could be considered as one of the major agricultural production systems in soil carbon storage. Similarly, livestock production systems also play an important role in maintaining the eco-system balance through nutrient recycling.
On the average, the number of livestock per household for most species increased during the Derge regime in the 1990s compared to the Haile Sellassie regime in the 1970s when people did not own land; and then the number declined in the 2000s except for equines, crossbreeds and oxen. The change to crop intensification led to the change in the purpose for livestock keeping. Farmers started keeping certain types of animals for specific purposes unlike before when livestock was kept for prestige and economic security. The major drive for the change of attitude towards the purpose of keeping livestock was scarcity of resources, mainly feed and water. Equine ownership has significantly increased due to their low off-take rate and their feeding habits which allowed them to survive in harsh environments where feed resources were extremely scarce.
There was a significant difference in crop response to manure application. Vegetables produced higher yields with manure than chemical fertilizers. Cereals on the other hand responded more to chemical fertilizers than to manure. Therefore, combining manure and chemical fertilizers was the best option for the sustainability of crop production in the study area. Some of the limitations to the use of manure as an organic fertilizer were inadequate manure production, high labour cost, bulkiness and high cost of transport to the fields and weed infestation. Manure management systems in the study area were affected by livestock husbandry practices. Only crossbred cattle (5%) were zero-grazed and used; and manure was stored in pits as slurry. Indigenous cattle were grazed outdoors in the fields during the day and at night they were kept in kraals near homesteads. There was a substantial loss of nutrients during the day when animals were grazing in the fields through leaching and trampling of dung and urine patches. Indoor or zero grazing of livestock could reduce nutrient losses.
The use of manure as fuel in the study area had no significant effect on CO2 emissions at household or local level, but had a negative impact on soil organic carbon storage and soil fertility. Therefore, for improved yield and balanced eco-systems manure burning has to be replaced by other alternative energy sources such as bio-gas and kerosene. The largest carbon equivalent emissions were from CH4 (72.6%), N2O (24%) and CO2 (3.4%) which indicated the need to improve livestock and manure management systems under smallholder agriculture.
Overall, there was an indication of a decline in water resources on per capita basis. The major contributing factors were combined pressure of human and animal population on natural resources that led to excessive deforestation, loss of biological diversity, overgrazing, soil degradation and various forms of pollution and contamination. The global climate change also played a role in the decline in water resources due to the decrease in annual precipitation and increasing temperatures. Urbanization and economic growth increased the demand for milk and meat, which required additional water use for each unit of increased animal protein. The demand for milk and meat is expected to double in the next 20 years with an annual growth rate of between 2.5 to 4%.
From the sixty-year meteorological data (1951-2009) there was an established increase in rainfall by 2% per annum; and maximum and minimum temperature by 0.08oC per decade, which amounted to a cumulative temperature increase of 0.5oC in the last decade. The increase in precipitation and temperature favoured the adaption of lowland crops like maize and sorghum to highland agro-ecology. Climate prediction models forecasted that most of the highlands in Ethiopia will remain suitable for cereals like wheat and Teff for the next 50 to100 years. However, the perception of farmers indicated that they felt more heat and warm weather than they have experienced before. They reported that rainfall is now more erratic or comes late and stops earlier before plants completed their vegetative growth. / Environmental Sciences / D. Litt. et Phil. (Environmental Science)
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Impact on climate change and adaptation on cattle and sheep farming in the Eastern Cape Province of South AfricaMandleni, Busisiwe January 2011 (has links)
This study focused on the impact of climate change and adaptation on small-scale cattle and sheep
farming in the Eastern Cape province of South Africa. Using information from 500 livestock farmers
between 2005 and 2009 farming season, three methods of analysis were used to determine impacts of
climate change and adaptation. They were Principal Component Analysis (PCA), Binary Logistic
Regression Model (BLRM) and Heckman Probit Model (HPM). Findings revealed that cattle
production decreased during the study period 2005 to 2009. Preliminary descriptive statistics results
indicated that farmers had different perceptions on climate change and adaptation measures between
the periods 2005 and 2009. Further analysis using PCA showed that the different perceptions could
be grouped into: (i) drought and windy weather patterns; (ii) information and adaptation; (iii) climate
change extension services; (iv) intensive cattle and sheep production; and (v) temperatures. The
results of the BLRM indicated that the most significant factors that affected climate change and
adaptation were: (i) non-farm income per annum; (ii) type of weather perceived from 2005 to 2009;
(iii) livestock production and ownership; (iv) distance to weather stations; (v) distance to input
markets; (vi) adaptation strategies and (vii) annual average temperature. From the HPM the results
indicated that marital status, level of education, formal extension, temperatures and the way in which
land was acquired, significantly affected awareness on climate change. Variables that significantly
affected adaptation selections were gender, formal extension, information received on climate
change, temperatures and the way in which land was acquired.It was concluded that in the area of study, change in climate was already perceived by small-scale
cattle and sheep farmers. Households that perceived differences in seasonal temperatures during the
survey period were less likely to adapt to climate change. Having access to extension services
increased the likelihood of adaptation to climate change. Information on climate change to improve
livestock production appeared to play a significant role in the selection of adaptation measures. The
recommendation was that government should consider cattle and sheep farmers’ perceptions on
climate change when deciding on programmes for cattle and sheep production. It further suggested
that the most significant factors that affected climate change, adaptation, and awareness and
adaptation selections be considered when adaptation programmes are planned. / Agriculture Animal Health and Human Ecology / D.Phil. (Environmental Management)
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Avaliação de duas tecnologias de controle para acionamento de sistema de aquecimento resistivo em creche suína / Evaluation of two control technologies for activation of resistive heating system in swine nurseryBarros, Juliana de Souza Granja, 1986- 25 August 2018 (has links)
Orientador: Luiz Antonio Rossi / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-25T02:28:06Z (GMT). No. of bitstreams: 1
Barros_JulianadeSouzaGranja_M.pdf: 1975791 bytes, checksum: 57f688903342bc7bc27950bf884ac3b3 (MD5)
Previous issue date: 2014 / Resumo: O uso de sistemas de aquecimento em creches suínas é necessário para proporcionar conforto térmico e bem-estar aos animais dentro das instalações. A maioria dos equipamentos de fornecimento de calor utilizados na suinocultura demanda energia elétrica; cujo custo é sempre crescente. Portanto, há a necessidade de ajustes nos sistemas de aquecimento hoje empregados, com o intuito de viabilizar o uso racional de energia elétrica pelo setor. Deste modo, por meio da aplicação de um sistema eletrônico de controle da temperatura dentro das creches é possível manter o bem-estar e o desempenho produtivo do animal, com maior eficiência do uso de energia elétrica, em relação a dispositivos de controle tradicionais, como por exemplo, o termostato. O objetivo deste trabalho foi comparar duas tecnologias de controle de temperatura quanto ao uso racional de energia elétrica, manutenção das condições de conforto térmico e de desempenho produtivo dos animais em fase de creche. Os tratamentos estudados foram: resistências elétricas suspensas controladas por termostato digital simples, que representou a testemunha, e resistências elétricas suspensas controladas por controlador PID (Proporcional, integral e derivativo). Os tratamentos foram analisados quanto ao consumo de energia elétrica (kWh), consumo específico (kWh.kg? ¹), custo específico (R$.kg? ¹), demanda máxima de potência (kW), eficiência elétrica, ganho de peso (kg), conversão alimentar, taxa de mortalidade (%), temperatura de bulbo seco (°C), Índice de Temperatura e Umidade (ITU) e entalpia (kJ.kg? ¹ ar seco). O sistema de aquecimento resistivo com termostato manteve o ambiente mais tempo dentro da zona de conforto de temperatura em comparação ao sistema de aquecimento com controlador PID. No entanto, em relação aos índices de conforto térmico, o sistema de aquecimento com controlador PID proporcionou melhores condições de conforto em comparação ao sistema com termostato. Além disso, o sistema de aquecimento com controlador PID apresentou maiores valores de ganho de peso e menor consumo e custo específico de energia elétrica. Desta forma, concluiu-se que o sistema de aquecimento resistivo com controlador PID foi o que melhor atendeu as condições de conforto térmico dos leitões, foi o mais eficiente quanto ao uso de energia elétrica e o que proporcionou melhor desempenho produtivo aos animais / Abstract: The use of heating systems in nursery pigs is required to provide thermal comfort and welfare of animals within the facility. Most heat supply equipment used in swine electricity demand, whose cost is ever increasing. Thus, there is the need for adjustments to the heating systems used today, in order to facilitate the rational use of energy by industry. Thus, through the application of an electronic temperature control within the nurseries is possible to keep the welfare and the productive performance of the animal, more efficient use of electricity, compared to traditional control, such as example, the thermostat. The objective of this research had to compare two technologies for temperature control regarding the rational use of electricity, maintaining of thermal comfort and productive performance of the animals in the nursery phase. The treatments were: suspended electrical resistances controlled by a simple digital thermostat and suspended electrical resistances controlled by PID controller (proportional, integral and derivative). The treatments were analyzed regarding the electrical energy consumption (kWh), specific consumption (kWh.kg-¹), specific cost (R $.kg-1), maximum demand (kW), electrical efficiency, weight gain (kg), feed conversion, mortality rate (%), dry bulb temperature (° C), Temperature and Humidity Index (THI) and enthalpy (kJ.kg- ¹ dry air). The resistive heating system with thermostat kept more time environment within the comfort zone temperature compared to the heating system with the PID controller. However, regarding to thermal comfort indices, the heating system with PID controller provided better comfort conditions compared to the system with thermostat. Furthermore, the heating system with PID controller showed higher weight gain and lower specific consumption and cost of electricity. The resistive heating system with PID controller was that better provided the conditions for thermal comfort of pigs, was the most efficient regarding the use of electrical energy and which provided better performance for the animals / Mestrado / Construções Rurais e Ambiencia / Mestra em Engenharia Agrícola
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Assessment of environmental-livestock interactions in crop-livestock systems of central Ethiopian highlandsNigatu Alemayehu Minase 09 1900 (has links)
The study was done in Adaa district which is one of the 12 districts in East Shoa zone in Oromia regional state of Ethiopia. It is located southeast of Addis Ababa at 38o51’ 43.63’’ to 39o04’ 58.59’’ E and 8o46’ 16.20’’ to 8o59’ 16.38’’ N, on the western margin of the Great East African Rift Valley. The altitude ranges from 1 500 to ≥ 2 000 meters above sea level. The district has a high potential for mixed livestock and crop production systems. The purpose of this study was to make up for the paucity of information on livestock and environment interaction by assessing the relationship of livestock, soil, water, land, climate and crops under mixed crop-livestock production systems in central Ethiopian highlands.
The objectives of the study were: (a) to assess the effect of change in land management on carbon storage and the contribution of livestock to carbon storage; (b) to examine the impact of livestock on natural resources and the environment; (c) to assess the effects of the change in traditional agricultural practices, expansion of factories, slaughter houses, greenhouses and flower farms on water and soil quality; (d) to evaluate the effect of climate change on livestock production under small-scale agriculture; and (e) to recommend options for mitigation and adaptation to environmental changes.
The research design was non-experimental and did not involve the manipulation of the situation, circumstances or experiences of the interviewees. The design was comparative research that compared two or more groups on one or more variables, such as the effect of agricultural land use management, tillage type etc. on carbon storage in the soil. This research also applied a longitudinal design that examined variables such as the performance exhibited by groups over time. Purposive sampling was often used to measure the effect of agricultural, industrial effluent and human interferences on the environment by measuring nutrient contents at sources in the soil, water and manure. Biological data were complemented by key socio-economic survey by interviewing individual farmers and focus groups from sampling sites. Secondary data were also reviewed to measure soil degradation and run-off attributed to livestock.
Results showed that animal waste and farmyard manure had the highest contribution in the addition of carbon in the soil. This implied that for most of carbon inputs livestock products and by-products had a greater place in the carbon sink. Therefore, livestock production could be considered as one of the major agricultural production systems in soil carbon storage. Similarly, livestock production systems also play an important role in maintaining the eco-system balance through nutrient recycling.
On the average, the number of livestock per household for most species increased during the Derge regime in the 1990s compared to the Haile Sellassie regime in the 1970s when people did not own land; and then the number declined in the 2000s except for equines, crossbreeds and oxen. The change to crop intensification led to the change in the purpose for livestock keeping. Farmers started keeping certain types of animals for specific purposes unlike before when livestock was kept for prestige and economic security. The major drive for the change of attitude towards the purpose of keeping livestock was scarcity of resources, mainly feed and water. Equine ownership has significantly increased due to their low off-take rate and their feeding habits which allowed them to survive in harsh environments where feed resources were extremely scarce.
There was a significant difference in crop response to manure application. Vegetables produced higher yields with manure than chemical fertilizers. Cereals on the other hand responded more to chemical fertilizers than to manure. Therefore, combining manure and chemical fertilizers was the best option for the sustainability of crop production in the study area. Some of the limitations to the use of manure as an organic fertilizer were inadequate manure production, high labour cost, bulkiness and high cost of transport to the fields and weed infestation. Manure management systems in the study area were affected by livestock husbandry practices. Only crossbred cattle (5%) were zero-grazed and used; and manure was stored in pits as slurry. Indigenous cattle were grazed outdoors in the fields during the day and at night they were kept in kraals near homesteads. There was a substantial loss of nutrients during the day when animals were grazing in the fields through leaching and trampling of dung and urine patches. Indoor or zero grazing of livestock could reduce nutrient losses.
The use of manure as fuel in the study area had no significant effect on CO2 emissions at household or local level, but had a negative impact on soil organic carbon storage and soil fertility. Therefore, for improved yield and balanced eco-systems manure burning has to be replaced by other alternative energy sources such as bio-gas and kerosene. The largest carbon equivalent emissions were from CH4 (72.6%), N2O (24%) and CO2 (3.4%) which indicated the need to improve livestock and manure management systems under smallholder agriculture.
Overall, there was an indication of a decline in water resources on per capita basis. The major contributing factors were combined pressure of human and animal population on natural resources that led to excessive deforestation, loss of biological diversity, overgrazing, soil degradation and various forms of pollution and contamination. The global climate change also played a role in the decline in water resources due to the decrease in annual precipitation and increasing temperatures. Urbanization and economic growth increased the demand for milk and meat, which required additional water use for each unit of increased animal protein. The demand for milk and meat is expected to double in the next 20 years with an annual growth rate of between 2.5 to 4%.
From the sixty-year meteorological data (1951-2009) there was an established increase in rainfall by 2% per annum; and maximum and minimum temperature by 0.08oC per decade, which amounted to a cumulative temperature increase of 0.5oC in the last decade. The increase in precipitation and temperature favoured the adaption of lowland crops like maize and sorghum to highland agro-ecology. Climate prediction models forecasted that most of the highlands in Ethiopia will remain suitable for cereals like wheat and Teff for the next 50 to100 years. However, the perception of farmers indicated that they felt more heat and warm weather than they have experienced before. They reported that rainfall is now more erratic or comes late and stops earlier before plants completed their vegetative growth. / Environmental Sciences / D. Litt. et Phil. (Environmental Science)
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