Spelling suggestions: "subject:"soil degradation."" "subject:"oil degradation.""
121 |
Waldkonversion und Bodendegradation in Bergnebelwaldgebieten Guatemalas (Alta Verapaz) / Ein Beitrag zur Biodiversitätsforschung in sensiblen tropischen Ökosystemen / Forest Conversion and Soil Degradation of Tropical Montane Cloud Forests in Guatemala (Alta Verapaz) / Investigation in the framework of biodiversity research in sensitive tropical ecosystemsMarkussen, Michael 03 November 2003 (has links)
No description available.
|
122 |
Waldkonversion und Bodendegradation im tropischen Tiefland von Ostbolivien / GIS-gestützte Analyse zur Regionalisierung der Bodendegradation im Department Santa Cruz / Forest conversion and soil degradation in the tropical lowland of Eastern-Bolivia / GIS-based analysis for regionalization of soil degradation in the Santa Cruz departmentKrüger, Jens-Peter 20 January 2006 (has links)
No description available.
|
123 |
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.
|
124 |
Land degradation in Mhondoro (Zimbabwe) : an environmental assessment of communal land uses and resource management practiceTichagwa, Cornelius Gibson 04 1900 (has links)
Thesis (MA)--Stellenbosch University, 2002. / ENGLISH ABSTRACT: When land loses its intrinsic qualities or suffers a decline in its capabilities it is said to be
degraded. Land degradation manifests itself in various forms such as deforestation, soil
erosion, land, air and water pollution. In the context of sustainable development land
degradation has become one of the world's major concerns. Now, more than ever before,
it has become urgent to carry out empirical studies on the nature and extent of land
degradation and to come up with appropriate responses to the problem.
In much of the developing world communal natural resource management practices are
common. It is often assumed that communal exploitation of common property resources
such as woodlands, pastures, water sources and wildlife inevitably leads to land
degradation. This is due to the belief that humankind would seek to derive maximum
benefit from common pool resources without incurring any costs towards the
conservation of those resources.
This study was an environmental assessment of the impacts of communal land-use
systems and common property resources management practices in the Mhondoro
communal lands of Zimbabwe. The area has been subject to human settlement for over a
century and is regarded as a typical representation of a well-established communal land
management system. Several methods were used to make the assessment. These included
the following: a questionnaire survey; interviews with key informants; soil and vegetation
traverses and field measurements; tree density counts in demarcated plots; calculation of
the population density and livestock density for the study area; completion of an
environmental evaluation matrix and a communal projects sustainability index checklist;
and analysis of geo-referenced time-lapse aerial photography covering a fifteen year
period (1982-1997).
It was established that serious land degradation had occurred in Chief Mashayamombe's
ward in Mhondoro. Degradation manifested itself in the form of soil erosion and stream
sedimentation, woodland depletion, pasture degradation and wildlife habitat destruction. Communal land-use and natural resource management practices are only partially to
blame for this state of affairs. The fragile nature of the sandy soils of the uplands, the
sadie soils of the vlei areas, combined with the fairly high rainfall amounts (annual
average 750mm) make the area prone to soil erosion. Rainfall intensity tends to be high
in the area and when the rain falls on the poorly vegetated, and highly erodible soils
erosion occurs. The land has become severely stressed due to over-utilisation; a
population density of 93 people per km2 and livestock density of 110 cattle per km2 were
recorded. The land available for communal settlement in the area has been limited in
extent. Due to the general poverty of the communal farmers the replacement of nutrients
into the cultivated soil has not kept pace with the deteriorating condition of the land.
Contrary to popular misconceptions, communal area residents have shown concern for
environmental conservation through fallowing their fields, gully reclamation efforts,
grazing schemes, woodland preservation and tree growing practices. Remedial and/or
mitigatory measures for the environmental recovery of the area could adopt some of these
well-established practices and incorporate them in a whole-catchment management
strategy.
Key words
Land degradation, environmental degradation, pollution, environmental assessment,
common property resources, communal land uses, sustainable resources management,
sustainability indicators, soil erodibility, soil erosivity / AFRIKAANSE OPSOMMING: Wanneer grond sy intrinsieke waarde verloor of 'n afname in sy vermoë toon, kan gesê
word dat die grond gedegradeer is. Gronddegradasie manifesteer in verskeie vorme, soos
ontbossing, gronderosie, grond, lug en water besoedeling. Gronddegradasie het binne die
konteks van volhoubare ontwikkeling wêreldwyd van besondere belang geword. Nou, meer
as ooit vantevore, is dit noodsaaklik om empiriese studies uit te voer aangaande die aard en
omvang van gronddegradasie, en om vorendag te kom met toepaslike reaksies tot die
probleem.
Gemeenskaps natuurlike hulpbron bestuur praktyke is algemeen in die ontwikkelende
wêreld. Daar word dikwels veronderstel dat uitbuiting van gemeenskaplike eiendoms
hulpbronne deur die gemeenskap, soos woude, weivelde, waterbronne en wild,
onvermeidelik lei na gronddegradasie. Hierdie aanname het ontwikkel as gevolg van die
oortuiging dat die mensdom daarna sal streef om maksimum voordeel te trek uit
gemeenskaplike hulpbronne, sonder om enige koste aan te gaan ten opsigte van die
bewaring daarvan.
Hierdie studie behels 'n omgewings evaluering van die impakte van gemeenskaps
grondgebruik sisteme en gemeenskaplike eiendoms hulpbron bestuur praktyke in die
Mhondoro gemeenskaplike grond van Zimbabwe. Die area word al vir meer as 'n eeu deur
mense bewoon, en word beskou as 'n tipiese voorbeeld van 'n gevestigde gemeenskaps
grondbestuur sisteem. Verskeie metodes is toegepas met die evaluering, en sluit in: 'n
vraelys opname; onderhoude met sleutel segspersone; grond en plantegroei opnames en
veldopnames; boom digtheidstelling in afgebakende persele; berekening van bevolkingsen
veedigtheid vir die studiegebied; opstelling van 'n omgewing evaluerings matriks en 'n
gemeenskap projek volhoubaarheids indeks kontroleerlys; en 'n analise van geo-referenced
time-lapse lugfoto's wat strek oor 'n tydperk van 15 jaar (1982-1997).
Daar is vasgestel dat ernstige gronddegradasie voorkom in Hoofman Mashayamombe se
wyk in Mhondoro. Degradasie word gemanifesteer in die vorm van gronderosie en stroom
sedimentasie, uitputting van woude, weiveld degradasie en die verwoesting van wild
habitatte. Gemeenskaps grondgebruik en natuurlike hulpbron bestuurspraktyke is net gedeeltelik verantwoordelik vir die stand van sake. Gronderosie vind plaas ook as gevolg
van die sensitiewe aard van die sanderige grond van die hoogland, die sodic grond van die
vlei areas, in kombinasie met redelike hoë reënval (gemiddeld 750mm per jaar). Reënval
intensiteit in die area is geneig om hoog te wees, en erosie vind plaas wanneer reën val op
die hoogs erodeerbare grond wat met yl plantegroei bedek is. Die grond verkeer onder
geweldige druk as gevolg van oorbenutting; 'n bevolkingsdigtheid van 93 mense per km2
en veedigtheid van 110beeste per km2 is aangeteken. Die grond beskikbaar vir vestiging
van gemeenskappe word in omvang beperk. Die vervanging van grondvoedingstowwe in
bewerkte grond hou nie tred met die agteruitgang in die kondisie van die grond nie, as
gevolg van die algemene armoede van die gemeenskapsboere.
Inwoners van die gemeenskapsarea , teenstrydig met algemene wanopvattings, toon
besorgdheid ten opsigte van omgewingsbewaring deur die grond braak te lê, donga
herwinnings pogings, wei velds planne, bewaring van woude en praktyke ten opsigte van
die groei van bome. Remediërende en/of versagtende maatstawwe vir die herstel van die
omgewing kan van hierdie gevestigde praktyke inkorporeer in 'n bestuursstrategie wat die
hele opvangsgebied insluit.
Sleutelwoorde
Gronddegradasi e, omgewingsde gradasi e, besoedeling, omgewingsassessering,
gemeenskaplike eiendoms hulpbronne, gemeenskaplike grondgebruik, volhoubare
hulpbron bestuur, volhoubaarheids aanwysers, grond erodeerbaarheid, grond verwering.
|
125 |
Restoring degraded soils with organic matter: a case study of the restoration process in macadamia orchards, Limpopo ProvinceNonyana, Thambulo Aubrey 05 August 2015 (has links)
MENVSC / Department of Environmental Sciences
|
126 |
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.
|
127 |
COncepts and costs for the maintenance of productive capacity: a study of the measurement and reporting of soil qualityO'Brien, Patricia Ann, patricia.o'brien@rmit.edu.au January 1999 (has links)
This thesis studies the role accounting plays in the monitoring and reporting of soil quality in one sector of the agricultural industry, broadacre farming. A survey was conducted with broadacre farmers in the Loddon Catchment, Victoria, Australia. The primary aim was to determine the effectiveness accounting plays in providing information to decision makers relative to the productive capacity in soil quality and not just on profits. The capital asset in this study was defined as soil quality. Soils and soil quality in particular, are major elements in determining land value. The concern is decisions are being made by potential buyers and other decision makers, particularly policy makers, with regards to soil quality on the basis of incomplete and often misleading information. It is proposed that a major reason is due to the fact that different participants in the agricultural and accounting industries require and use different information. The accounting systems used by farmers are those that have been developed for the manufacturing sector which may not be appropriate for managing long-term, complex resources such as soil. The farmers themselves did not find formal accounting reports useful for decision making because these reports are based on uniform standards and market prices. The topic of soil quality and land degradation is viewed from two perspectives. In one perspective, the proprietary view; the accounting emphasis is on the ownership of assets and the change, both in income and capital, in these assets over time. In this case the accounting equation is seen as assets - liabilities = equities. The proprietor takes all the risk. A more recent perspective in accounting, the entity view, emphasises the assets whether financed from equity or debt and where the accounting equation is seen as assets = equities. The emphasis changes to the income flow from these assets and more interest is shown in current market prices as a reflection of the future value of these assets Profit is not necessarily a good indicator of what farmers are doing for their capital asset. There needs to be greater emphasis on costs undertaken for the conservation of soil. Those costs should be considered an investment and put into the balance sheet and not the profit and loss statement. The major finding of study demonstrates that decision making groups have different
|
128 |
Identificação de possíveis áreas afetadas por sais no Perímetro Irrigado de São Gonçalo por meio do sensoriamento remoto. / Identification of possible areas affected by salts in the Irrigated Perimeter of São Gonçalo through remote sensingOLIVEIRA, Woslley Sidney Nogueira de. 10 May 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-05-10T18:06:15Z
No. of bitstreams: 1
WOSLLEY SIDNEY NOGUEIRA DE OLIVEIRA - DISSERTAÇÃO PPGSA ACADÊMICO 2018..pdf: 7059892 bytes, checksum: 1ab51771320e5bbd6c88d3c01b4b7aeb (MD5) / Made available in DSpace on 2018-05-10T18:06:15Z (GMT). No. of bitstreams: 1
WOSLLEY SIDNEY NOGUEIRA DE OLIVEIRA - DISSERTAÇÃO PPGSA ACADÊMICO 2018..pdf: 7059892 bytes, checksum: 1ab51771320e5bbd6c88d3c01b4b7aeb (MD5)
Previous issue date: 2018-02-22 / Os perímetros irrigados implantados no Estado da Paraíba são considerados uma
alternativa econômica bastante rentável, promove a geração de empregos e aumenta a disponibilidade de alimentos. Devido ao manejo inadequado do solo e da água, isso têm causado perdas na qualidade do solo desses perímetros, degradando-os principalmente por salinização. O sensoriamento remoto é uma alternativa tecnológica de baixo custo, boa frequência temporal e possui a capacidade de mapear áreas em processo de desertificação. Essa pesquisa têm por objetivo identificar possíveis áreas afetadas por sais no Perímetro Irrigado de São Gonçalo (PISG), Sousa- PB, por meio de técnicas de sensoriamento remoto. Para esse estudo foi utilizado imagens do satélite LANDSAT 8/OLI (média resolução espacial), órbita 216 / ponto 65 da data de 23/11/2016; imagem do software Google Earth Pro® da data de 29/02/2016 para servir como imagem auxiliar e registros fotográficos das áreas in loco. Realizou-se a técnica de classificação supervisionada, utilizando o SCP (semi- automatic plugin) no software QGIS (Quantum Gis). A aferição da qualidade da classificação se deu por meio da validação cruzada,
utilizando de parâmetros estatísticos como a exatidão do produtor (EP), exatidão do
usuário (EU), exatidão global (EG) e índice Kappa. A classe área supostamente
salinizada (ASS) apresentou EP e EU de 89.15% e 88.88%, respectivamente. O
índice Kappa resultou em um valor de 0.8684, a classe ASS foi classificada como
sendo de qualidade excelente. A qualidade geral da classificação é avaliada tanto
pela EG que apresentou um valor de 0.9350 como pelo índice Kappa geral com
valor de 0.9252, sendo valores que representam uma classificação de qualidade
excelente. A classe ASS apresentou os maiores valores mínimos e máximos de fator
de refletância em todas as bandas da imagem, destacando a banda 6 de valores
0.47 e 0.67, respectivamente. O valor da área classificada como sendo da classe
ASS foi de 1736.75 hectares, 31% da área total do PISG. As imagens analisadas
possibilitaram discriminar áreas salinizadas e não salinizadas mediante as
diferenças de tonalidade e de refletância. As imagens analisadas com o plugin SCP
possibilitaram a realização de um mapa de classificação supervisionada, indicando a
variabilidade espacial das áreas propícias ao processo de salinização. No entanto,
recomenda- se a análise dos parâmetros físicos e químicos do solo dessas áreas
para o aumento da confiabilidade na qualidade desse tipo de mapeamento. / The irrigated perimeters implemented in the State of Paraiba are considered a costeffective
alternative quite profitable, promotes the generation of jobs and increases
the availability of food. Due to inadequate management of soil and water, that have
caused losses in soil quality of these perimeters, degrading them mainly by
salinization. Remote sensing is an alternative low-cost technology, good temporal
and frequency has the ability to map areas in process of desertification. This
research aim to identify potential areas affected by salts in the irrigated perimeter of
São Gonçalo (PISG), Sousa-PB, through remote sensing techniques. For this study
we used LANDSAT satellite images 8/OLI (average spatial resolution), 216/orbit point
65 of 07/11/2016 date; image of the Google Earth Pro software® from date of
29/02/2016 to serve as auxiliary image and photographic records of the areas on the
spot. The supervised classification technique, using the SCP (semi-automatic plugin)
in software QGIS (Quantum Gis). The measurement of the quality of the classification
took place by means of cross-validation, using statistical parameters such as the
accuracy of the producer (EP), accuracy of the user (EU), global (EG) accuracy and
Kappa index. The area class supposedly salinated (.ASS) presented EP and I of
89.15% and 88.88%, respectively. The Kappa index resulted in a value of .ASS class
0.8684 was classified as being of excellent quality. The overall quality of the
classification is assessed both by EG who presented a 0.9350 value as the Kappa
index 0.9252 valued General, being values that represent a rating of excellent
quality. The class ASS presented the largest minimum and maximum values of
reflectance factor in all the bands in the image, highlighting the band 6 0.47 values
and 0.67, respectively. The value of the area classified as being of .ASS class was
1736.75 acres, 31% of the total area of the PISG. The images reviewed discriminate
salinated areas and not allowed saline through the variations of shade and
reflectance. The images analyzed with the SCP plugin enabled the creation of a map
of supervised classification, indicating the spatial variability of the areas prone to
salinization process. However, it is recommended that the analysis of the physical
and chemical soil parameters of these areas for increased reliability in the quality of
this type of mapping.
|
129 |
Hodnocení kvality/zdraví půdy v blízkosti obce Bohaté Málkovice / Assessment health/quality of the soil near the village Bohaté MálkoviceSuchá, Kateřina January 2019 (has links)
Diploma thesis evaluates quality and healthiness of the soil health located close to Bohate Malkovice focusing on changes in both physical and chemical characteristics of the soil in time. The theoretical part describes physical, chemical, and biological parameters of the soil. Selected physical parameters are structure, texture, determination of measured weight, bulk density of the soil, porosity, actual volumetric water content of the soil, aeration, saturated and unsaturated hydraulic conductivity, infiltration, and colour. Chosen chemical parameters are pH, carbonates, soil electrical conductivity, and humus content. Picked biological parameters are microbial biomass, respiration, nitrogen content, and weed infestation. The practical part analyses selected indicators of quality of the soil from the location of the experiment close to Bohate Malkovice. The area under evaluation has been treated using reduced tillage for long term. The practical part is based on the laboratory examination of disturbed and undisturbed soil samples taken between years 2016 and 2018. Based on outcome results we can evaluate the quality of the soil considering plants growth, development, and soil fertility.
|
Page generated in 0.1365 seconds