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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Agricultural land evaluation: the adaptation of the land evaluation and site assessment system to the microcomputer

Spackman, Michael. January 1985 (has links)
Call number: LD2668 .T4 1985 S642 / Master of Landscape Architecture
12

Planning the use of stony lands in south-western Quebec : a feasibility study

Seecharan, Randolph. January 1984 (has links)
This study investigates the agronomic and economic feasibility of utilizing stony lands for crop production in South-Western Quebec where stoniness is the major constraint. / Field experiments conducted on stony soils indicated significant differences in yields of grain corn and silage corn between stone treatments. With oats, however, there were no significant differences in yields. / Regression analysis of bare land values indicated an inverse relationship between size of stony land and unit price. A similar relationship also existed for land clearing and reclamation machinery costs for different farm sizes. / Linear programming optimization for farms within two agricultural sub-zones showed that variation in net income is due to economies of scale, differences in yields and subsidy arrangements. For small farms, additional subsidy is required to make them economically attractive. Post-optimal procedures indicated that the base solutions are more sensitive to crop yields and prices than reclamation costs. / The study concludes that crop production on stony lands is feasible within the parameters defined and that it might be more economical for an operator to develop under-utilized reserves of stony lands rather than purchase prime land at current market prices.
13

Desenvolvimento e calibração de um protótipo de sensor de umidade do solo para aplicação em sistemas de irrigação / Development and calibration of a prototype soil moisture sensor for application in irrigation systems

Rodrigues, Paulo Sérgio Lobo 05 September 2017 (has links)
A importância da água na agricultura para o sucesso das lavouras é inquestionável. Nos tempos atuais, a irrigação tornou-se ferramenta estratégica para o sucesso das produções. Dentre outros benefícios, está a possibilidade de plantio de entre safras, o que possibilita melhorar o aproveitamento da área agrícola. Uma maior produtividade também pode ser alcançada por meio do uso artificial de condução de água às lavouras. No entanto, deve-se buscar o equilíbrio entre os interesses da produção com os critérios socioambientais. Outrossim, a disponibilização de água em excesso pode acarretar prejuízos, causando a proliferação de fungos e bactérias, e do possível apodrecimento das raízes. Desta forma, a irrigação de lavouras deve demandar controles eficientes do conteúdo de água no solo, primando pelo uso racional e ecologicamente sustentável dos recursos naturais envolvidos. É sabido que existem diversos sensores de umidade do solo que são capazes de obter o teor de água no solo, e que podem auxiliar no controle do uso da água. No entanto, os altos custos dos sensores de qualidade continuam sendo uma barreira para a implantação em lavouras de pequenos produtores, devido aos seus frágeis poderes aquisitivos. Motivado por isso, este trabalho buscou desenvolver um protótipo de sensor que possibilitasse a aferição da umidade do solo, sendo que a premissa principal seria o baixo custo. Para isso foi necessário realizar a calibração do protótipo, a partir de leituras simultâneas entre o mesmo e o equipamento de referência, o sensor profissional Watermark modelo 200SS-5. De forma acessória, o protótipo foi projetado para comunicar-se com plataformas externas, afim de possibilitar a integração e o monitoramento em tempo real. Os dados foram transmitidos para o banco de dados por intermédio da tecnologia wireless do microcontrolador ESP8266-12E (placa NodeMCU). Duas plataformas foram utilizadas, a ThingSpeak, bem como outra desenvolvida por este autor para o específico fim de integração com o protótipo. O custo para o desenvolvimento do protótipo correspondeu a 4,2% do valor correspondente ao sensor Watermark, possuindo características adicionais em comparação ao equipamento de referência, como a comunicação com meios externos e a fácil integração com sistemas de irrigação automatizada. / The importance of water in agriculture for the success of crops is unquestionable. In the present times, irrigation has become a strategic tool for the success of productions. Among other benefits is the possibility of planting between harvests, which makes it possible to improve the utilization of the agricultural area. Higher productivity can also be achieved through the artificial use of water to the crops. However, a balance must be struck between the interests of production and the socio-environmental criteria. Also, the availability of water in excess can lead to damages, causing the proliferation of fungi and bacteria, and the possible rotting of the roots. In this way, irrigation of crops should demand efficient controls of soil water content, emphasizing the rational and ecologically sustainable use of the natural resources involved. It is known that there are several soil moisture sensors that are able to obtain the water content in the soil, and that can aid in the control of water use. However, the high costs of quality sensors continue to be a barrier to the implantation in crops of small producers, due to their fragile purchasing power. Motivated by this, this work sought to develop a prototype sensor that would allow the measurement of soil moisture, and the main premise would be the low cost. For this, it was necessary to carry out the calibration of the prototype, from simultaneous readings between the same and the reference equipment, the professional sensor Watermark model 200SS-5. Of accessory form, the prototype was designed to communicate with external platforms, possibiliting the integration and real-time monitoring. For the database the data were transmitted through the wireless technology of the ESP8266-12E microcontroller (NodeMCU board). Two platforms were used, the ThingSpeak, as well a another developed by this author for the specific purpose of integration with the prototype. The cost for the prototype development corresponded to 4.2% of the value corresponding to the Watermark sensor, having additional characteristics compared to the reference equipment, the such as communication with external means and the easy integration with automated irrigation systems.
14

Desenvolvimento e calibração de um protótipo de sensor de umidade do solo para aplicação em sistemas de irrigação / Development and calibration of a prototype soil moisture sensor for application in irrigation systems

Rodrigues, Paulo Sérgio Lobo 05 September 2017 (has links)
A importância da água na agricultura para o sucesso das lavouras é inquestionável. Nos tempos atuais, a irrigação tornou-se ferramenta estratégica para o sucesso das produções. Dentre outros benefícios, está a possibilidade de plantio de entre safras, o que possibilita melhorar o aproveitamento da área agrícola. Uma maior produtividade também pode ser alcançada por meio do uso artificial de condução de água às lavouras. No entanto, deve-se buscar o equilíbrio entre os interesses da produção com os critérios socioambientais. Outrossim, a disponibilização de água em excesso pode acarretar prejuízos, causando a proliferação de fungos e bactérias, e do possível apodrecimento das raízes. Desta forma, a irrigação de lavouras deve demandar controles eficientes do conteúdo de água no solo, primando pelo uso racional e ecologicamente sustentável dos recursos naturais envolvidos. É sabido que existem diversos sensores de umidade do solo que são capazes de obter o teor de água no solo, e que podem auxiliar no controle do uso da água. No entanto, os altos custos dos sensores de qualidade continuam sendo uma barreira para a implantação em lavouras de pequenos produtores, devido aos seus frágeis poderes aquisitivos. Motivado por isso, este trabalho buscou desenvolver um protótipo de sensor que possibilitasse a aferição da umidade do solo, sendo que a premissa principal seria o baixo custo. Para isso foi necessário realizar a calibração do protótipo, a partir de leituras simultâneas entre o mesmo e o equipamento de referência, o sensor profissional Watermark modelo 200SS-5. De forma acessória, o protótipo foi projetado para comunicar-se com plataformas externas, afim de possibilitar a integração e o monitoramento em tempo real. Os dados foram transmitidos para o banco de dados por intermédio da tecnologia wireless do microcontrolador ESP8266-12E (placa NodeMCU). Duas plataformas foram utilizadas, a ThingSpeak, bem como outra desenvolvida por este autor para o específico fim de integração com o protótipo. O custo para o desenvolvimento do protótipo correspondeu a 4,2% do valor correspondente ao sensor Watermark, possuindo características adicionais em comparação ao equipamento de referência, como a comunicação com meios externos e a fácil integração com sistemas de irrigação automatizada. / The importance of water in agriculture for the success of crops is unquestionable. In the present times, irrigation has become a strategic tool for the success of productions. Among other benefits is the possibility of planting between harvests, which makes it possible to improve the utilization of the agricultural area. Higher productivity can also be achieved through the artificial use of water to the crops. However, a balance must be struck between the interests of production and the socio-environmental criteria. Also, the availability of water in excess can lead to damages, causing the proliferation of fungi and bacteria, and the possible rotting of the roots. In this way, irrigation of crops should demand efficient controls of soil water content, emphasizing the rational and ecologically sustainable use of the natural resources involved. It is known that there are several soil moisture sensors that are able to obtain the water content in the soil, and that can aid in the control of water use. However, the high costs of quality sensors continue to be a barrier to the implantation in crops of small producers, due to their fragile purchasing power. Motivated by this, this work sought to develop a prototype sensor that would allow the measurement of soil moisture, and the main premise would be the low cost. For this, it was necessary to carry out the calibration of the prototype, from simultaneous readings between the same and the reference equipment, the professional sensor Watermark model 200SS-5. Of accessory form, the prototype was designed to communicate with external platforms, possibiliting the integration and real-time monitoring. For the database the data were transmitted through the wireless technology of the ESP8266-12E microcontroller (NodeMCU board). Two platforms were used, the ThingSpeak, as well a another developed by this author for the specific purpose of integration with the prototype. The cost for the prototype development corresponded to 4.2% of the value corresponding to the Watermark sensor, having additional characteristics compared to the reference equipment, the such as communication with external means and the easy integration with automated irrigation systems.
15

The Impact of the Physical and Cultural Geography of Southeastern Utah on Latter-Day Settlement

Mandurino, Sally Timmins 01 January 1998 (has links) (PDF)
The Latter-day Saint settlements in southeastern Utah, namely Bluff, Monticello and Blanding, were impacted by the physical and cultural geography of the area. These geographic elements hindered, and in some cases prevented, the Latter-day Saint colonizers from fulfilling the seven basic principles of Latter-day Saint expansion and colonization in the Great Basin. The impacts of physical geography were the geology, the climate, the soil and the rivers and streams. The impacts of cultural geography were the Navajo Indian Tribe, the Paiute Indian Tribe, and the criminal element. This thesis discusses the geographic elements of the area, how they impacted the settlements of Bluff, Monticello and Blanding, how the Mormons reacted to the situation, and how the impacts were eventually dealt with and solved.
16

Planning the use of stony lands in south-western Quebec : a feasibility study

Seecharan, Randolph. January 1984 (has links)
No description available.
17

A bioresource classification for KwaZulu-Natal, South Africa.

Camp, Kelson Gerald Temple. January 1999 (has links)
The classification of Bioresource Units (BRUs) was developed to provide a reconnaissance appraisal of the natural resources for both environmental impact assessments and the agricultural potential of KwaZulu- Natal. Storage of the Bioresource Programme in a geographical information system (GIS) facilitates usage. Of the criteria used for the classification of BRUs, climate (rainfall and temperature in particular), was considered to be the most important factor. Other factors used were the soil association codes of the Land Types, plant indicator species and communities, and terrain type. The base map used for the study was the 1 : 50 000 topo-cadastral map on which the Land Types (LTs) were demarcated. The result of the study was the mapping of 590 BRUs, each of which is sufficiently homogeneous in environmental factors (climate, soil association, vegetation type and terrain form), such that uniform land use practices, production techniques and levels, can be defined with a reasonable degree of accuracy. Ecotopes, based on LT information, were defined for each BRU. An ecotope is a class of land, defined according to soil characteristics, within which agricultural production will be uniform and will differ significantly between one ecotope and another. The ecotopes, both for cropping and veld, are not spatially defined, but expressed as percentages of the total area of the BRU. In the BRU inventory, crops suitable for the BRU and each ecotope, and the level of production (tons/ha/annum) in the case of crop ecotopes, are supplied at a stated level of management. In addition, it is possible to investigate the potential for 29 crops for which crop production models exist, and for any other crop providing its growth and site requirements, particularly climate and soil, are known. Additional crop production models will be developed, as the demand for this type of information is high. Veld management norms, such as grazing capacity, are supplied for the veld ecotopes. On the completion of the classification of BRUs the decision was made to develop a third level of classification and the Bioresource Groups (BRGs) were mapped. In the classification of the BRUs 23 vegetation types had been identified and used as one of the criteria for BRU demarcation. By grouping all the BRUs with the same vegetation type, BRGs were defined. Each BRG, therefore, consists of a specific vegetation type containing one or more BRUs of the same vegetation type. The 23 BRGs are used mainly for regional and veld management planning. The programme was designed for use by a wide range of people with individual skills and knowledge, and contains most of the information needed for land use planning. It is essential however, to be able to identify ecotopes in the field to effectively use the information at a detailed level for farm planning. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 1999.
18

A land suitability evaluation for improved subsistence agriculture using GIS : the case study of Nkwezela, KwaZulu-Natal, South Africa.

January 2007 (has links)
Rural farmers in the Nkwezela Area, with an average family size of 10 people, face a number of problems. The crops that are predominantly cultivated in the area, for subsistence (maize, dry beans, sorghum, potatoes, cabbages and turnips) have very low yields compared to the potential yield of the land. Natural resources in the area are increasingly deteriorating. In addition, arable land has shown remarkable signs of soil erosion that may lead to loss of soil fertility. This study evaluates the current land suitability for subsistence agriculture in Nkwezela based on climatic, soil, topographic and crop requirement data collected from different sources. The spatial parameters of the land resources were digitally encoded into a GIS database to create thematic layers of the land resources which was then compared to the crop requirement data of the selected crops grown in Nkwezela namely, maize, sorghum, dry beans, potatoes, cabbages and turnips. A GIS was used to overlay the thematic layers of the resources to select areas that satisfied the crop requirements of the selected crops. The results of the analysis of the land evaluation in the study area showed that the very hot summers, very cold winters together with the high clay content in the soils are the two limiting factors in Nkwezela. The land suitability maps indicate that sorghum is highly suitable in the area with dry beans and maize being relatively suitable. Cabbages are the least the least adapted crop with potatoes and turnips being not suitable due to the high temperatures during the growing season and the very cold winters. In conclusion Nkwezela is in a high rainfall area that is suitable for subsistence agriculture where warm season crops like dry beans, maize and sorghum are used for daily consumption by the community and can be cultivated in a sustainable manner. In addition the correct farming methods, procedures, liming and fertiliser requirements must be implemented, adhered to and maintained in order to improve crop yields in a sustainable manner and to encourage subsistence agriculture by the community. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2007.
19

Evaluating agricultural potential of a Cape Metropolitan Catchment : a fuzzy logic approach

Fourie, Johannes Christoffel 12 1900 (has links)
Thesis (MSc (Geography and Environmental Studies))--University of Stellenbosch, 2006. / Sustainable use of the earth’s resources is seen by many authorities as critical to ensure the planet’s survival. In this regard agriculture is seen as a major role player and fundamental link in the chain of sustainability. South Africa, a country with relatively little favourable agricultural land, should therefore preserve high potential areas for agricultural purposes. The Western Cape, with 75% of all medium-potential arable land in South Africa, is a valuable asset. One region targeted for development and where uncertainty prevails regarding its agricultural potential, is the G21B catchment in the Atlantis Growth Corridor (AGC). The AGC is envisaged as long-term growth axis for the Cape Metropole, but conflicting opinions exist on its agricultural possibilities and suitability to absorb urban growth. Consequently, the aim of this project was to evaluate the suitability of this catchment for a number of agricultural landuses. Fuzzy logic, a modification of the land evaluation approach originally developed by the Food and Agricultural Organization of the United Nations (FAO), was used to address this problem. Input data consisted of a soil map and digital elevation model (DEM) of the area. Parameters identified from these sources and applicable to the study were soil texture of the first, second and third horizons, as well as coarse fragments in the top soil, wetness, weathered rock, average pH, effective root depth, and slope. These parameters were compared to the requirements of six landuses, i.e. wheat, wine grapes, potatoes, tomatoes, onions, and citrus, and a fuzzy representation for every landuse was constructed. Expert opinion aided in a weighting process whereby the relative weights of parameters were computed and incorporated into the evaluation. Results showed extensive areas with a relatively high agricultural potential for potatoes and wine grapes. In addition, areas with potential were also identified for wheat, citrus, and tomatoes, albeit on more limited scale. Large areas, however, were deemed unsuitable for the aforementioned agricultural crops and would therefore be suitable to absorb metropolitan growth or to be maintained as conservation areas. The fuzzy logic approach provided insightful results. Problematic parameters were easily identified and no information was lost in the evaluation process. It also allowed for an objective quantitative comparison between crops. This provided freedom in deciding which landuse should be practiced, especially if the focus is on a sustainable rather than the most productive crop.
20

Assessing land capability, soil suitability and fertility status for sustainable banana production at Makuleke Farm

Swafo, Seome Michael January 2022 (has links)
Thesis (M.Sc. (Soil Science)) -- University of Limpopo, 2022 / In South Africa, land use planning has received limited attention in areas perceived as suitable for agricultural production. In the lack of reliable soil type and fertility status information, crop yields remain lower than the land’s potential, with subsequent land degradation. Despite this, studies that focused on land capability and soil suitability to date have not considered the spatial variability of the soil nutrients and factors influencing their variability. However, this information is key for site-specific soil management. Therefore, it is vital to link land capability and soi suitability with the spatial variability of soil nutrients as it opens opportunities for more rational management of the soil resources since soil nutrients directly affect crop growth and consequently yield. To address this issue, a study was conducted on a 12 ha banana plantation portion of the Makuleke farm. The main objectives of this study were to (1) survey, classify and characterise soils in order to derive and map land capability classes of Makuleke farm, (2) quantify the physical and chemical properties of the soils in order to derive and map the soil suitability of Makuleke farm for banana production, (3) assess the spatial variability and structure of soil nutrients across the Makuleke farm and (4) Identify the factors of control of the spatial variability of the soil nutrients across the Makuleke farm. To begin with, a field soil survey was conducted using transect walks complemented by auger observations to sub-divide the 12 ha banana plantation portion of the farm into varied soil mapping units. Thereafter, soil classification was done to group soils based on their morphological properties and pedological processes. During soil classification, a total of 12 representative profile pits (1.5 m × 1.5 m long × 2 m deep/limiting layer) were excavated, studied, described, and sampled. At each profile pit, three replicates samples were collected at 0 – 30 cm depth intervals giving rise to 36 bulk soil samples. From the gathered soil profile information, four soil units were thus delineated and identified across the 12 ha banana plantation. For soil fertility assessment, a grid sampling strategy at 50 × 50 m was adopted to collect the samples across the 12 ha banana plantation. A total of 27 composite samples were collected at the nodes of the grid, and thereafter bagged, labelled, and transported to the laboratory. In the laboratory, all collected samples were air-dried and sieved using a 2 mm sieve in preparation for soil physical and chemical properties analysis. The land capability assessment of Makuleke farm was done using the concepts and principles of the FAO framework for Land Evaluation (FAO, 1976), but adapted to South African conditions by Smith (2006). Soil suitability assessment was done using the FAO framework for Land Evaluation (FAO, 1976) coupled with the guidelines for rainfed agriculture (FAO, 1983) and the criteria proposed by Sys et al. (1993) and Naidu et al. (2006). To assess the spatial variability and structure of the soil nutrients across the farm, classical and geostatistical techniques were employed respectively. A correlation matrix was employed to identify key factors influencing the spatial variability of soil nutrients across the farm. For interpolation, ordinary kriging was used to generate soil nutrient spatial distribution maps. In this study, four soil forms were identified and classified as Hutton, Westleigh, Glenrosa, and Valsrivier, which are broadly distinguished as Lixisols, Plinthosols, Leptosols, and Cambisols. Land capability results revealed that 17% of the 12 ha portion of the farm has very high arable potential (I), 60% of the farm has medium arable potential (III), 6% has low arable potential (IV) and 17 % is non-arable (VI), which might explain the varied banana yields in the farm. Soil suitability analysis revealed that 12% of the 12 ha farm is highly suitable (S1), 34% is moderately suitable (S2), 38% is marginally suitable (S3) and 16% is permanently not suitable (N2) for banana production. The low arable and marginally suitable portion of the farm was under Valsrivier soils which were limited by its shallow depth, shallow rooting depth, acidic soil pH, low organic carbon (OC), and the fact that it was located on a steeper slope gradient. The non-arable and not suitable portion of the farm for banana production was under Glenrosa and it was limited by its location on a steep slope gradient and was characterised by shallow effective rooting depth, low OC, low clay content, and acidic soil pH. Classical statistical techniques revealed that phosphorus (P), potassium (K), calcium (Ca), zinc (Zn), manganese (Mn), and copper (Cu) content varied highly across the banana plantation, while magnesium (Mg) and total nitrogen (TN) varied moderately. In addition, the geostatistical analysis revealed that spatial dependency was weak (Ca, Cu, and TN), moderate (Mg and Zn), and strong (P, K, and Mn) for the different soil nutrients across the 12 ha banana plantation. Soil nutrients with strong spatial dependency have a good spatial structure and are easily manageable (in terms of fertilisation, liming, and irrigation) across the farm compared to the ones with weak spatial dependency which have a poor structure. This study also found that land attributes, which are soil type and topographic position were the main factors driving the spatial variability of the soil nutrients across the farm. In terms of soil type, soils such as Valsrivier and Glenrosa with 2:1 clay-type smectite were the ones that had nutrient content compared to soils with 1:1 clay-type kaolinite (e.g., Westleigh and Hutton). Higher nutrient contents were also observed in the footslope position compared to the middleslope of the farmland. Correlation analysis revealed that Mn was the key polyvalent cation influencing the spatial variability of P, K, and Zn. Soil pH and effective cation exchanges capacity (ECEC) were the key soil factors driving the spatial variability of Ca, while ECEC was the key factor affecting the spatial variability of Mg. Moreover, the spatial variability of soil Mn and Cu was driven by soil Cu and clay content, respectively. The kriged maps showed that P, Mg, Zn, and Mn were high in the northeast part and low in the northwest part of the farm. Similarly, K and Ca were low in the northwest part, but they were high in the south to the southwest part of the study area. Total nitrogen was high in the west part and low in the east-northeast part, while Cu was evenly distributed across the plantation. This study highlights the importance of prior land use planning (i.e., land capability and soil suitability) and fertility assessment for agricultural production. The research results obtained provide the actual reference state of the capability of the land for arable farming and soil suitability for banana production at Makuleke farm. Moreover, the research results provide the spatial variability and structure of the soil nutrients which have a greater impact on the growth and yield of bananas. The results obtained in this study will be useful for site-specific management of soil nutrients and other soil management practices (e.g., irrigation, fertilisation, liming, etc.), developing appropriate land use plans, and quantifying anthropogenic impacts on the soil system and thus improving land productivity. / National Research Foundation (NRF)

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