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Sistema de apoio ao processo de decisão para a gestão do uso agricola da terra / Decison support system for agricultural land use managementGiboshi, Monica Luri 17 February 2005 (has links)
Orientadores: Luiz Henrique Antunes Rodrigues, Francisco Lombardi Neto / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-04T17:43:04Z (GMT). No. of bitstreams: 1
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Previous issue date: 2005 / Resumo: Este trabalho teve como objetivo o desenvolvimento de um sistema de apoio à decisão para a gestão da terra, integrando um Sistema Especialista para determinar a capacidade de uso da terra e outro para recomendar usos adequados e as práticas de conservação e manejo do solo, um Sistema de Informações Geográficas (SIG), uma base de dados e uma interface para interpretar a entrada de dados do usuário e as mensagens passadas entre os sub-sistemas. Todos os diálogos entre o usuário e o sistema são realizados pela da interface, assim como a comunicação entre os componentes do sistema desenvolvido. Os sistemas especialistas foram desenvolvidos utilizando o ¿shell¿ conhecido como CLIPS (C Language Integrated Production System) que provê um ambiente para a construção de sistemas especialistas. O SIG utilizado foi o IDRISI, versão 32, que possui o módulo Applications Programming Interface - API (Interface de Programação de Aplicativos) com um OLE Automation Server, possibilitando o uso de linguagens de alto nível, tais como Visual Basic, para controlar as operações do Idrisi32. A base de dados foi desenvolvida com a utilização do Microsoft Access®, além disso, é de fácil acesso, pois a maioria dos usuários tem esse aplicativo instalado em seus computadores. O sistema desenvolvido determina a capacidade de uso da terra; recomenda usos adequados para cada classe de capacidade de uso; recomenda práticas de conservação e manejo do solo; e identifica áreas de conflito comparando os mapas de uso da terra da região em estudo com o mapa de capacidade de uso. Todos os resultados podem ser visualizados em janelas do programa, gravados ou impressos em formas de relatórios. A validação do sistema foi feita comparando as saídas do sistema com os resultados obtidos de quatro especialistas. As divergências encontradas mostraram que o sistema desenvolvido foi mais rigoroso, principalmente no que diz respeito ao risco de erosão, determinando classes de capacidade de uso diferentes das determinadas por alguns especialistas. Quanto ao tipo de uso e às práticas de conservação e manejo do solo, foram poucas as divergências encontradas. A área utilizada para testar o sistema é o Município de Santo Antônio do Jardim - SP. O sistema classificou 36,95% das terras do município como adequadas para a utilização com cultura anual ou perene; 42,69% são adequadas para pastagem e reflorestamento e 19,51% devem ser utilizadas para preservação ambiental. Outro resultado apresentado é o mapa de intensidade de uso, no qual pôde se observar que 48,50% do município está sendo utilizada de forma adequada; 31,82% com uso inadequado e, 14,06% apresenta subutilização. O sistema mostrou ser uma ferramenta poderosa e eficaz, permitindo avaliar uma região, dando suporte para uma tomada de decisão mais fundamentada / Abstract: The objective of this work was to develop a decision support system for agricultural land environmental planing, which integrates an Expert System to determine the land capability and other to recommend adequate uses and practices for soil conservation and management, Geographic Information System (GIS), a database and an interface to monitor input and output data and the messages passed between the subsystems. The management of all the system is made by an interface developed in Visual Basic, version 5.0. All the dialogues between the user and the system as well as the communication with the components of the system are made through the interface that shows windows, menus, dialog boxes, maps and reports in the screen. It saves the results in files and prints them. The expert systems were developed with a shell known as CLIPS (C Language Integrated Production System), that provides an environment for building expert systems. The GIS was IDRISI, version 32, that has Applications Programming Interface ¿ API with an OLE Automation Server, and makes possible to use high-level languages, such as Visual Basic for controlling the operation of Idrisi32. The database was developed with the Microsoft Access®, because of the majority of the users have this software installed in its computers. The developed system determines land capability from information stored in the database and, also supplied for the SIG, through the soil and slope maps; it recommends adequate uses for land capability class; it recommends practices for soil conservation and management and identifies conflict areas comparing the maps of land use with the land capability. All the results can be visualized by the user through windows of the program, recorded or printed in forms of reports. The validation of the system was done comparing the system outputs with the results obtained of four experts. The divergences have shown that the system was more rigorous than the experts, specially concerning the erosion risk, leading to different land capability classes from those determined for some experts, in some cases. Concerning to the type of practices for soil conservation and management, the divergences have been few. In order to test the system, the county of Santo Antônio do Jardim ¿ SP was selected. The system classified 36.95% of lands as adequate for the use with annual or perennial cultures; 42.69% are adequate for pastures and reforestation and 19.51% must be used for environmental preservation. Another presented result is the map of intensity use, through which could be observed that 48.50% of the lands are being used of adequate form; 31.82% of the lands presents inadequate use and, 14.06% presents under utilization. The system is a powerful and efficient tool, what makes it possible to evaluate a region and give support to a more adequate decision making / Doutorado / Planejamento e Desenvolvimento Rural Sustentável / Doutor em Engenharia Agrícola
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Chemical nature and plant availability of phosphorus present in soils under long-term fertilised irrigated pastures in Canterbury, New ZealandCondron, Leo M. January 1986 (has links)
Soil P fractionation was used to examine changes in soil inorganic and organic P under grazed irrigated pasture in a long-term field trial at Winchmore in Mid-Canterbury. The soil P fractionation scheme used involved sequential extractions of soil with O.5M NaHCO₃ @ pH 8.5 (NaHCO₃ P), 0.1M NaOH (NaOH I P), 1M HCl (HCl P) and 0.1M NaOH (NaOH II P). The Winchmore trial comprised 5 treatments: control (no P since 1952), 376R (376 kg superphosphate ha⁻¹ yr⁻¹ 1952-1957, none since), 564R (564 kg superphosphate ha⁻¹ yr⁻¹ 1952-1957, none since) 188PA (188 kg superphosphate ha⁻¹ yr⁻¹ since 1952) and 376PA (376 kg superphosphate ha⁻¹ yr⁻¹ since 1952: Topsoil (0-7.5cm) samples taken from the different treatments in 1958, 1961, 1965, 1968, 1971, 1974 and 1977 were used in this study. Changes in soil P with time showed that significant increases in soil inorganic P occurred in the annually fertilised treatments (l88PA, 376PA). As expected, the overall increase in total soil inorganic P between 1958 and 1977 was greater in the 376PA treatment (159 µg P g⁻¹) than that in the 188PA treatment (37 µg P g⁻¹). However, the chemical forms of inorganic P which accumulated in the annually fertilised treatments changed with time. Between 1958 and 1971 most of the increases in soil inorganic P in these treatments occurred in the NaHCO₃ and NaOH I P fractions. On the other hand, increases in soil inorganic P in the annually fertilised treatments between 1971 and 1977 were found mainly in the HCl and NaOH II P fractions. These changes in soil P forms were attributed to the combined effects of lime addition in 1972 and increased amounts of sparingly soluble apatite P and iron-aluminium P in the single superphosphate applied during the 1970's. In the residual fertiliser treatments (376R, 564R) significant decreases in all of the soil inorganic P fractions (i.e. NaHCO₃ P, NaOH I P, HCl P, NaOH II p) occurred between 1958 and 1977 following the cessation of P fertiliser inputs in 1957. This was attributed to continued plant uptake of P accumulated in the soil from earlier P fertiliser additions. However, levels of inorganic P in the different soil P fractions in the residual fertiliser treatments did not decline to those in the control which indicated that some of the inorganic P accumulated in the soil from P fertiliser applied between 1952 and 1957 was present in very stable forms. In all treatments, significant increases in soil organic P occurred between 1958 and 1971. The overall increases in total soil organic P were greater in the annually fertilised treatments (70-86 µg P g⁻¹) than those in the residual fertiliser (55-64 µg P g⁻¹) and control (34 µg P g⁻¹) treatments which reflected the respective levels of pasture production in the different treatments. These increases in soil organic P were attributed to the biological conversion of native and fertiliser inorganic P to organic P in the soil via plant, animal and microbial residues. The results also showed that annual rates of soil organic P accumulation between 1958 and 1971 decreased with time which indicated that steady-state conditions with regard to net 'organic P accumulation were being reached. In the residual fertiliser treatments, soil organic P continued to increase between 1958 and 1971 while levels of soil inorganic P and pasture production declined. This indicated that organic P which accumulated in soil from P fertiliser additions was more stable and less available to plants than inorganic forms of soil P. Between 1971 and 1974 small (10-38 µg P g⁻¹) but significant decreases in total soil organic P occurred in all treatments. This was attributed to increased mineralisation of soil organic P as a result of lime (4 t ha⁻¹) applied to the trial in 1972 and also to the observed cessation of further net soil organic P accumulation after 1971. Liming also appeared to affect the chemical nature of soil organic P as shown by the large decreases in NaOH I organic P(78-88 µg P g⁻¹) and concomitant smaller increases in NaOH II organic P (53-65 µg P g⁻¹) which occurred in all treatments between 1971 and 1974. The chemical nature of soil organic P in the Winchmore long-term trial was also investigated using 31p nuclear magnetic resonance (NMR) spectroscopy and gel filtration chromatography. This involved quantitative extraction of organic P from the soil by sequential extraction with 0.1M NaOH, 0.2M aqueous acetylacetone (pH 8.3) and 0.5M NaOH following which the extracts were concentrated by ultrafiltration. Soils (0-7.5cm) taken from the control and 376PA annually fertilised treatments in 1958, 1971 and 1983 were used in this study. 31p NMR analysis showed that most (88-94%) of the organic P in the Winchmore soils was present as orthophosphate monoester P while the remainder was found as orthophosphate diester and pyrophosphate P. Orthophosphate monoester P also made up almost all of the soil organic P which accumulated in the 376PA treatment between 1958 and 1971. This indicated that soil organic P in the 376PA and control treatments was very stable. The gel filtration studies using Sephadex G-100 showed that most (61-83%) of the soil organic P in the control and 376PA treatments was present in the low molecular weight forms (<100,000 MW), although the proportion of soil organic P in high molecular weight forms (>100,000 MW) increased from 17-19% in 1958 to 38-39% in 1983. The latter was attributed to the microbial humification of organic P and indicated a shift toward more complex and possibly more stable forms of organic P in the soil with time. Assuming that the difference in soil organic P between the control and 376PA soils sampled in 1971 and 1983 represented the organic P derived from P fertiliser additions, results showed that this soil organic P was evenly distributed between the high and low molecular weight fractions. An exhaustive pot trial was used to examine the relative availability to plants of different forms of soil inorganic and organic P in long-term fertilised pasture soils. This involved growing 3 successive crops of perennial ryegrass (Lolium perenne) in 3 Lismore silt loam (Udic Ustochrept) soils which had received different amounts of P fertiliser for many years. Two of the soils were taken from the annually fertilised treatments in the Winchmore long term trial (188PA, 376PA) and the third (Fairton) was taken from a pasture which had been irrigated with meatworks effluent for over 80 years (65 kg P ha⁻¹ yr⁻¹). Each soil was subjected to 3 treatments, namely control (no nutrients added), N100 and N200. The latter treatments involved adding complete nutrient solutions with different quantities of N at rates of 100kg N ha⁻¹ (N100) and 200kg N ha⁻¹ (N200) on an area basis. The soil P fractionation scheme used was the same as that used in the Winchmore long-term trial study (i.e. NaHCO₃ P, NaOH I P, HCl P, NaOH II p). Results obtained showed that the availability to plants of different extracted inorganic P fractions, as measured by decreases in P fractions before and after 3 successive crops, followed the order: NaHCO₃ P > NaOH I P > HCl P = NaOH II P. Overall decreases in the NaHCO₃ and NaOH I inorganic P fractions were 34% and 16% respectively, while corresponding decreases in the HCl and NaOH II inorganic P fractions were small «10%) and not significant. However, a significant decrease in HCl P (16%) was observed in one soil (Fairton-N200 treatment) which was attributed to the significant decrease in soil pH (from 6.2 to 5.1) which occurred after successive cropping. Successive cropping had little or no effect on the levels of P in the different soil organic P fractions. This indicated that net soil organic P mineralisation did not contribute significantly to plant P uptake over the short-term. A short-term field experiment was also conducted to examine the effects of different soil management practices on the availability of different forms of P to plants in the long-term fertilised pasture soils. The trial was sited on selected plots of the existing annually fertilised treatments in the Winchmore long-term trial (188PA, 376PA) and comprised 5 treatments: control, 2 rates of lime (2 and 4 t ha⁻¹ ) , urea fertiliser (400kg N ha⁻¹ ) and mechanical cultivation. The above ground herbage in the uncultivated treatments was harvested on 11 occasions over a 2 year period and at each harvest topsoil (0-7.5 cm) samples were taken from all of the treatments for P analysis. The soil P fractionation scheme used in this particular trial involved sequential extractions with 0.5M NaHCO₃ @ pH 8.5 (NaHCO₃ P), 0.1M NaOH (NaOH P), ultrasonification with 0.1M NaOH (sonicate-NaOH p) and 1M HCl (HCl P). In addition, amounts of microbial P in the soils were determined. The results showed that liming resulted in small (10-21 µg P g⁻¹) though significant decreases in the NaOH soil organic P fraction in the 188PA and 376PA plots. Levels of soil microbial P were also found to be greater in the limed treatments compared with those in the controls. These results indicated that liming increased the microbial mineralisation of soil organic P in the Winchmore soils. However, pasture dry matter yields and P uptake were not significantly affected. Although urea significantly increased dry matter yields and P uptake, it did not appear to significantly affect amounts of P in the different soil P fractions. Mechanical cultivation and the subsequent fallow period (18 months) resulted in significant increases in amounts of P in the NaHCO₃ and NaOH inorganic P fractions. This was attributed to P released from the microbial decomposition of plant residues, although the absence of plants significantly reduced levels of microbial P in the cultivated soils. Practical implications of the results obtained in the present study were presented and discussed.
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INFLUENCE OF SAMPLE DENSITY, MODEL SELECTION, DEPTH, SPATIAL RESOLUTION, AND LAND USE ON PREDICTION ACCURACY OF SOIL PROPERTIES IN INDIANA, USASamira Safaee (17549649) 09 December 2023 (has links)
<p dir="ltr">Digital soil mapping (DSM) combines field and laboratory data with environmental factors to predict soil properties. The accuracy of these predictions depends on factors such as model selection, data quality and quantity, and landscape characteristics. In our study, we investigated the impact of sample density and the use of various environmental covariates (ECs) including slope, topographic position index, topographic wetness index, multiresolution valley bottom flatness, and multiresolution ridge top flatness, as well as the spatial resolution of these ECs on the predictive accuracy of four predictive models; Cubist (CB), Random Forest (RF), Regression Kriging (RK), and Ordinary Kriging (OK). Our analysis was conducted at three sites in Indiana: the Purdue Agronomy Center for Research and Education (ACRE), Davis Purdue Agriculture Center (DPAC), and Southeast Purdue Agricultural Center (SEPAC). Each site had its unique soil data sampling designs, management practices, and topographic conditions. The primary focus of this study was to predict the spatial distribution of soil properties, including soil organic matter (SOM), cation exchange capacity (CEC), and clay content, at different depths (0-10cm, 0-15cm, and 10-30cm) by utilizing five environmental covariates and four spatial resolutions for the ECs (1-1.5 m, 5 m, 10 m, and 30 m).</p><p dir="ltr">Various evaluation metrics, including R<sup>2</sup>, root mean square error (RMSE), mean square error (MSE), concordance coefficient (pc), and bias, were used to assess prediction accuracy. Notably, the accuracy of predictions was found to be significantly influenced by the site, sample density, model type, soil property, and their interactions. Sites exhibited the largest source of variation, followed by sampling density and model type for predicted SOM, CEC, and clay spatial distribution across the landscape.</p><p dir="ltr">The study revealed that the RF model consistently outperformed other models, while OK performed poorly across all sites and properties as it only relies on interpolating between the points without incorporating the landscape characteristics (ECs) in the algorithm. Increasing sample density improved predictions up to a certain threshold (e.g., 66 samples at ACRE for both SOM and CEC; 58 samples for SOM and 68 samples for CEC at SEPAC), beyond which the improvements were marginal. Additionally, the study highlighted the importance of spatial resolution, with finer resolutions resulting in better prediction accuracy, especially for SOM and clay content. Overall, comparing data from the two depths (0-10cm vs 10-30cm) for soil properties predications, deeper soil layer data (10-30cm) provided more accurate predictions for SOM and clay while shallower depth data (0-10cm) provided more accurate predictions for CEC. Finally, higher spatial resolution of ECs such as 1-1.5 m and 5 m contributed to more accurate soil properties predictions compared to the coarser data of 10 m and 30 m resolutions.</p><p dir="ltr">In summary, this research underscores the significance of informed decisions regarding sample density, model selection, and spatial resolution in digital soil mapping. It emphasizes that the choice of predictive model is critical, with RF consistently delivering superior performance. These findings have important implications for land management and sustainable land use practices, particularly in heterogeneous landscapes and areas with varying management intensities.</p>
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The fate of nitrogen in lactose-depleted dairy factory effluent irrigated onto landFord, Colleen D. January 2008 (has links)
A two-year lysimeter study was undertaken to compare the environmental effects (e.g. nitrate leaching and nitrous oxide emissions) of soil applied lactose-depleted dairy factory effluent (LD-DFE) with lactose-rich DFE. The aim of this experiment was to determine the fate of nitrogen from LD-DFE and dairy cow urine applied to a Templeton fine sandy loam soil (Udic Ustrochrept), supporting a herbage cover of ryegrass (Lolium perenne) and white clover (Trifolium repens). Measurements were carried out on the amount of nitrogen lost from the soil via leaching, lost by denitrification, removed by the pasture plants, and immobilized within the soil organic fraction. Further, a comparison between the fate of nitrogen in LD-DFE irrigated onto land under a "cut and carry" system, as opposed to a "grazed" pasture system was undertaken. Lactose-depleted dairy factory effluent was applied at three-weekly intervals during the summer months at rates of 25 and 50 mm, until nitrogen loading targets of 300 and 600 kg N ha⁻¹ yr⁻¹ had been achieved. Measured leaching losses of nitrogen averaged 2 and 7 kg N ha⁻¹ yr⁻¹ for Control 25 and Control 50 treatments; 21, 20 and 58 kg N ha⁻¹ yr⁻¹ for 25 and 50 mm "cut and carry" treatments respectively; and 96 kg N ha⁻¹ yr⁻¹ for the 25 mm "grazed" treatment. The range of nitrate-N leaching loss from LD-DFE plus urine is no different from the lactose-rich DFE nitrate leaching loss. Uptake of nitrogen by the growing pasture averaged 153, 184,340,352,483, and 415 kg N ha⁻¹ yr⁻¹ for Control 25, Control 50, LD-DFE 25 and LD-DFE 50 mm "cut and carry" treatments, and the LD-DFE 25 mm "grazed" treatment, respectively. Denitrification losses were 0.06, 4.4, 1.69, 19.70, and 7.4 kg N ha⁻¹ yr⁻¹ for Control 25, the LD-DFE 25 "cut and carry" treatments, the LD-DFE 25 mm "grazed" treatment, and calculated "paddock losses", respectively. Isotopic nitrogen studies found that 29.4 and 25.8% of applied LD-DFE nitrogen was immobilised in the LD-DFE 25 and LD-DFE 50 "cut and carry" treatments. The results of this experiment confirm the findings of the previous lactose-rich DFE study, in that the effects of grazing stock are of greater environmental concern than the removal of lactose from the effluent waste stream.
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GIS-based land suitability assessment and allocation decision-making in a degraded rural environmenBreytenbach, Andre 10 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2006. / ENGLISH ABSTRACT: Rural development problems faced by the impoverished communities in the Transkei, South
Africa, are numerous, and environmental degradation has already taken much of its toll. By
working at a micro-catchment-level both the socio-economic and biophysical appreciation of the
land resources were captured as encapsulated in the concept of resource management domains.
Participatory decision-making allowed functional land use goals and evaluation criteria to be
incorporated into computerised multi-criteria evaluation and multi-objective land use allocation
models in order to reach an idealised or more sustainable land use situation. In the execution of the
decision-making process seven procedural steps were followed, which are discussed in detail and
applied in the case study. Synthesis of the results emphasised the envisaged rural planning
potential of the methods used. / AFRIKAANSE OPSOMMING: In terme van plattelandse ontwikkeling staar talle probleme die behoeftige gemeenskappe van
Transkei, Suid-Afrika, in die gesig en omgewingsdegradering neem ongehinderd sy tol. Deur op ‘n
mikro-opvangsgebied vlak te werk kon beide die sosio-ekonomiese en biofisiese waarde van die
gebied se hulpbronne bepaal word en uitgebeeld word in hulpbron bestuursdomeine. Deur
deelnemende besluitneming is funksionele grondgebruiksdoelwitte en evaluasie kriteria gebruik in
gerekenariseerde meervoudige kriteria evaluering en veeldoelige grondgebruiksaanwysingsmodelle
ten einde die ideale of ‘n meer volhoubare grondgebruik situasie te verkry. Vir die
uitvoering van die besluitnemingsproses is van sewe opeenvolgende stappe gebruik gemaak en die
uitvoering daarvan word in diepte bespreek in hierdie gevallestudie. Sintese van die resultate het
die potensiaal van hierdie beoogde landelike beplanningsmetodes beklemtoon.
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