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Aperfeiçoamento do emprego da equação universal de perda de solo na aplicação do pagamento por serviços ambientais da política espírito-santense de recursos hídricosRibeiro, Anna Paula Laje 31 August 2012 (has links)
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Previous issue date: 2012-08-31 / O mecanismo de Pagamento por Serviços Ambientais é um instrumento de gestão da Política de Recursos Hídricos do estado do Espírito Santo, que tem o projeto Produtores de Água como parte integrante. Este projeto baseia-se na conservação do solo para melhoria/conservação da qualidade das águas dos cursos d água e, para tanto, oferece uma compensação financeira àqueles que preservam ou reconstituem a vegetação das matas ciliares de estratégicas bacias hidrográficas do estado. A formulação deste projeto baseia-se, de forma simplificada, metodologicamente, em alguns fatores componentes da EUPS como parâmetros técnicos para determinação dos coeficientes de valoração. Nesse sentido, o presente trabalho tem por objetivo propor o aperfeiçoamento metodológico do emprego da EUPS no desenvolvimento do citado projeto. Para isso, os seguintes aspectos foram considerados e avaliados: utilização de ferramentas de geoprocessamento não utilizada pela metodologia atual; formulações para cálculo do fator topográfico LS mais condizentes com a realidade a metodologia vigente adota apenas três valores médios para a declividade S (32,5%, 60,0% e 87,5%), desconsidera valores de declividade inferiores a 20% e toma L como constante e igual a 100 metros; adoção de valores para o fator CP relativos a uso e manejo conservacionistas do solo a versão metodológica em vigor volta-se apenas para a conservação de florestas; e emprego do produto RK como fator de relativização espacial do esforço potencial para a redução de perda de solo na propriedade a metodologia vigente não analisa esse produto. No desenvolvimento do estudo foram utilizadas as três bacias hidrográficas em que o projeto Produtores de Água foi aplicado em sua fase experimental e 30 propriedades selecionadas das 197 que formaram o banco de dados do projeto em maio de 2011. Entre os resultados do estudo comparativo envolvendo a metodologia atual do projeto e metodologias visando seu aperfeiçoamento, têm-se: que há bastante diferença entre as duas técnicas abordadas de LS (calculado pela metodologia atual poderá ter seu valor subdimensionado ou superdimensionado se, respectivamente, o relevo for íngreme/plano) e, tomando a metodologia proposta como mais adequada, evidenciou-se o seu uso; o fator CP, quando da alteração do tipo de uso do solo mostrou-se bastante eficaz para reduzir a perda de solo potencial, entretanto, não foi sensível a análise desta característica no processo de evolução entre os estágios de regeneração florestal (capoeira, macega e vegetação secundária avançada/mata nativa); e o fator RK ressaltou que o distanciamento entre as propriedades impacta diretamente em sua variação, mostrando-se uma ferramenta importante de relativização espacial. No mais, foram propostas diretrizes para viabilizar a aplicação destes resultados em iniciativas de PSA, principalmente, no projeto Produtores de Água / The mechanism of Payment for Environmental Services is a management tool in water resources policy of the state of Espírito Santo, which has the project Produtores de Água as part of this. This project is based on soil conservation for improvement/maintenance of water quality of streams and, therefore, offers financial compensation to those that preserve or reconstruct the vegetation of the riparian forest of strategic watersheds in the state. The formulation of this project is based, in simplified form, methodologically, in some components of the USLE factors as technical parameters for determining the coefficients of valuation. Accordingly to these factors, this paper aims to propose a methodological improvement of the use of USLE in the development of that project. For this, the following aspects were considered and evaluated: use of GIS tools - not used by the current methodology, formulas for calculating the topographic factor LS more consistent with reality - the current methodology takes only three average values for the slope S (32.5%, 60.0% and 87.5%), ignores values less than 20% slope and take L to be constant and equal to 100 meters; adoption of CP values for the factor relating to the use and conservation management of soil - the version methodological back in force only for the conservation of forests, and RK use of the product as a factor of relativity space effort to reduce potential soil loss on the property - the current methodology does not review this product. In developing of this study, we used the three watersheds in what the project Produtores de Água was applied in its experimental phase and 30 of the 197 selected properties that formed the database of the project in may 2011. Among the results of a comparative study involving the current methodology of the project and methodologies aimed at improving it, follows that: that there is enough difference between the two techniques discussed in the LS (calculated using the current methodology may have its value be undersized or oversized, respectively, topography is steep / flat), and taking the proposed methodology as more appropriate, there was its use, the CP factor when changing the type of land use proved to be very effective in reducing soil loss potential, however , was not sensitive analysis of this feature in the evolution process between stages of forest, and factor RK noted that the distance between the properties directly impacts on their variation, being an important tool of relativity space. Other than that, guidelines were proposed to enable the implementation of these initiatives results in PES, especially in the design of Produtores de Água
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物質資源・環境資源としての木曽谷の森林 (2) -木曽谷の森林の環境保全的効用 -只木, 良也, TADAKI, Yoshiya, 鈴木, 道代, SUZUKI, Michiyo 12 1900 (has links) (PDF)
農林水産研究情報センターで作成したPDFファイルを使用している。
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Impact of Land Use and Climate Change on Hydrological Ecosystem Services (Water Supply) in the Dryland Area of the Middle Reaches of the Yellow RiverZhang, Lulu 08 October 2015 (has links)
Driven by many factors, the water supply services (streamflow and groundwater) of many rivers in the dryland area of China have declined significantly. This aggravates the inherent severe water shortages and results in increased severity in the water use conflicts that are threatening sustainable development in the region. Innovative strategies towards more water-efficient land management are vital for enhancing water quantity to ensure water supply security. A key step in the successful development and implementation of such measures is to understand the response of hydrological processes and related services to changes in land management and climate. To this end, it was decided to investigate these processes and responses in the upper reaches of the Jing River (Jinghe), an important meso-scale watershed in the middle reaches of the Yellow River on the Loess Plateau (NW China).
It has been shown that vegetation restoration efforts (planting trees and grass) are effective in controlling soil erosion on the Loess Plateau. Shifts in land cover/use lead to modifications of soil physical properties. Yet, it remains unclear if the hydraulic properties have also been improved by vegetation restoration. A better understanding of how vegetation restoration alters soil structure and related soil hydraulic properties, such as water conductivity and soil water storage capacity, is necessary. Three adjacent sites, with comparable soil texture, soil type, and topography but contrasting land cover (Black locust forest, grassland, and cropland), were investigated in a small catchment in the upstream Jinghe watershed (near Jingchuan, Gansu province). Seasonal variations of soil hydraulic properties in topsoil and subsoil were examined. Results revealed that the type of land use had a significant impact on field-saturated, near-saturated hydraulic conductivity, and soil water characteristics. Specifically, conversion from cropland to grass or forests promotes infiltration capacity as a result of increased saturated hydraulic conductivity, air capacity, and macroporosity. Moreover, conversion from cropland to forest tends to promote the formation of mesopores that increase soil water storage capacity. Tillage in cropland temporarily created well-structured topsoil, but also compacted subsoil, as indicated by low subsoil saturated hydraulic conductivity, air capacity, and plant available water capacity. An impact of land cover conversion on unsaturated hydraulic conductivities was not identified, indicating that changes in land cover do not affect functional meso- and microporosity. Changes in soil hydraulic properties and associated hydrological processes and services due to soil conservation efforts need to be considered, should soil conservation measures be implemented in water-limited regions for sustaining adequate water supply.
To differentiate between the impacts of land management and climate change on streamflow, the variation of annual streamflow, precipitation, potential evapotranspiration, and climatic water balance in a small catchment of the upstream Jinghe watershed (near Pingliang, Gansu province) was examined during the period of 1955 – 2004. During this time the relative contributions of changes in land management and climate to the reduction of streamflow were estimated. A statistically significant decreasing trend of -1.14 mm y-1 in annual streamflow was detected. Furthermore, an abrupt streamflow reduction due to afforestation and construction of terraces and check-dams was identified around 1980. Remarkably, 74% of the total reduction in mean annual streamflow can be attributed to the soil conservation measures. Among various conservation measures, streamflow could be considerably reduced by afforestation and terracing (including damland creation), due to their low contribution to water yield. In contrast, slope farmland and grassland can maintain a certain level of water supply services due to higher runoff coefficients. According to a meta-analysis of the published studies on the Loess Plateau, the impact of changes in land management on annual streamflow appears to diminish with increasing catchment size while the impact of climate change appears uniform across space. This means that there is a dependency between the catchment size and the response of hydrological processes to environmental change. At least at the local scale, it appears that well-considered land management may help to ensure the water supply services.
Due to limited surface water availability, groundwater is an essential water source for supporting ecosystem and socio-economic development in the dryland region. However, the groundwater process is susceptible and vulnerable to changes in climate and landscape (i.e., land cover and form) that in turn can result in profound adverse consequences on water supply services in water-limited regions. In addition, an improved understanding of the response of groundwater related processes to natural and artificial disturbances is likely to ensure more secure and more sustainable governance and management of such regions, as well as better options for adapting to climate change. Yet, this topic has seldom been researched, especially in areas that have already experienced large-scale alteration in landscape and are located in dryland regions, such as the Loess Plateau. Therefore, an investigation of the baseflow variation along the landscape change was conducted. The average annual baseflow has significantly decreased at catchment scale during the period of 1962 – 2002 without any obvious significant change in climate. At decadal scale, the reduction accounts for approximately 9% in the 1970s, 48% in the 1980s, and 92% in the 1990s, while the baseflow index declines averaging 5%, 16% and 67%, respectively. All of the monthly baseflow levels dropped at varying rates except in January, among which July was the most severe in terms of both magnitude (-4.17) and slope (-0.09 mm y-1). In perspective of landscape change, landform change (terrace and check-dam) tends to reduce baseflow by reallocation of surface fluxes and retention for crop growth causing limited deep drainage in other areas. Land cover change (i.e., afforestation) reduced the baseflow to a larger extent by enhanced evapotranspiration and thus hampered deep drainage as suggested by the soil moisture measurement underneath. The study indicates that knowledge about baseflow formation on catchment scale needs further improvement. Integrated soil conservation and water management for optimizing landscape structure and function in order to balance soil (erosion) and water (supply) related hydrological ecosystem services is vital.
The governing processes to the changes of water-supply-services-related hydrological process (e.g., streamflow) are assumed to be different across space. To this end, the factors controlling streamflow were investigated on both a small and large scale. Streamflow in small catchments was found to be mainly controlled by precipitation and land cover type. On a larger scale, evaporative demand was found to be another additional major driving force. Hydrological modeling is a frequently used tool for the assessment of impacts of land use and climate change on water balance and water fluxes. However, application of the Soil and Water Assessment Tool (SWAT) model in the upstream Jinghe watershed was unsuccessful due to difficulties in calibration. The inability of the SWAT model to take the influence of terraces on steep slopes into consideration and the method how to calculate lateral flow were the main reasons for unsatisfactory calibration, at least for the current version of SWAT used in this study. Alternatively, Budyko’s frameworks were applied to predict the annual and long-term streamflow. However, the effect of changes in land management (e.g., afforestation) on streamflow could not be assessed due to a lack of vegetation factors. Therefore, an empirical analysis tool was derived based on an existing relationship for estimation. This method was found to be the most effective in reproducing the annual and long-term streamflow. The incorporation of temporal changes in land cover and form in the approach enables the estimation of the possible impact of soil conservation measures (e.g., afforestation or terracing). The importance of adaptive land management strategies for mitigating water shortage and securing the water supply services on the Loess Plateau was highlighted.
A cross-sectoral view of the multiple services offered by managed ecosystems at different spatial scales under changing environments needs to be integrated to improve adaptive land management policy. In a water limited environment, such as the Loess Plateau, multiple ecosystem services including hydrological services need to be balanced with minimum trade-offs. This can only be achieved when management is based on a holistic understanding of the interdependencies among various ecosystem services and how they might change under alternative land management.
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Biologischer Abbau organischer Substanz bei unterschiedlichem Wassergehalt in einem ModellversuchBirth, Volker 11 June 2019 (has links)
In der Landnutzung stellt die Bewertung der Versorgung mit organischer Bodensubstanz (OBS) eine besondere Herausforderung dar. Dabei wird der Einfluss der Bodenfeuchte aufgrund des globalen Klimawandels an Bedeutung gewinnen, da die Wasserverfügbarkeit Einfluss auf die Aktivität der bodenlebenden Mikroorganismen nimmt. Ziel der Arbeit waren daher Aussagen, inwieweit verschiedene Wassergehalte den biologischen Umsatz bei der Inkubation von Bodenproben mit unterschiedlicher Herkunft sowie organischer Düngung beeinflussen. In einem Modellversuch wurden Bodenproben ungedüngter Parzellen von drei deutschen Dauerfeldversuchen in einer zweifaktoriellen Blockanlage in Abhängigkeit von organischer Düngung (Weizenstroh, Stallmist) und Wassergehalt inkubiert. Die Experimente wurden in vier Feuchtigkeitsstufen mit 10, 40, 65 und 90 % der Feldkapazität über einen Zeitraum von 85 Tagen bei einer Temperatur von 25 °C realisiert. Zusätzlich sind vor und nach der Inkubation Thermogravimetrische Bodenanalysen (TGBA) durchgeführt worden.
Die Ergebnisse belegen einen mit dem Wassergehalt steigenden C-Umsatz, da die Aktivität von aeroben Mikroorganismen bis zur Wassersättigung des Bodens zunimmt. Die Steigerung war bei Zugabe von Weizenstroh höher als bei Stallmist, ohne Düngerzusatz signifikant niedriger. Gleichzeitig änderte sich die Dynamik der Abbauprozesse. Durch besonders trockene Verhältnisse wurde die Umsetzung verzögert, zudem sank die Umsatzrate langsamer. Ein dauerhafter Einfluss des Standorts auf den Umsatz der Düngemittel war dagegen nicht nachweisbar. Der biologische Abbau im Inkubationsversuch veränderte darüber hinaus die thermische Zerfallsdynamik. Die größten Veränderungen wurden nach Zugabe von Stroh festgestellt. Nicht geklärt werden konnte, ob in Böden mit höherer Versorgung durch organische Substanz gleiche Ergebnisse erzielt werden können. / In land use, the assessment of the supply of organic soil matter (OBS) is a particular challenge. The influence of soil moisture on global climate change will become increasingly important, as water availability influences the activity of soil-living microorganisms. The aim of the work is therefore to determine the extent to which different water contents influence the biological turnover during the incubation of soil samples with different origins as well as organic fertilisation. In a model experiment, soil samples from unfertilized plots of three German long-time field experiments were incubated in a two-factor block facility depending on organic fertilization (wheat straw, manure) and water content. The experiments were carried out in four humidity levels with 10, 40, 65 and 90 % of the field capacity over a period of 85 days at a temperature of 25 °C. In addition, thermogravimetric soil analyses (TGBA) were performed before and after incubation.
The results prove a C turnover increasing with the water content, since the activity of aerobic microorganisms increases until the water saturation of the soil. The increase was higher with the addition of wheat straw than with manure, without fertilizer significantly lower. At the same time, the dynamics of the degradation processes changed. Due to particularly dry conditions, conversion was delayed and the turnover rate fell more slowly. A lasting influence of the site on fertilizer turnover was not proved. In addition, the biological degradation in the incubation experiment changed the thermal decay dynamics. The largest changes were observed after the addition of straw. It could not be clarified whether the same results could be achieved in soils with a higher supply of organic matter.
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Obosnovanie parametrov kovšej zemlečerpatel'nych snarjadov dlja glubokovodnoj dobyči organo-mineral'nych osadkov / Bucket tool design for mining deep-sea organic-mineral sedimentsShepel, Taras 21 April 2015 (has links) (PDF)
The thesis is devoted to determining the parameters of the bucket to increase productivity of dredgers while mining deep-water organic-mineral sediments. It was achieved by increasing the fill factor through determining the rational geometrical parameters of the bucket. Analytical dependencies of the rational height and length of the bucket on the cutting parameters and physical-and-mechanical properties of the excavated sediments were determined. Expressions for defining forces while digging plasticity water-saturated soils were developed. Experimental investigations of the process of digging deep-water organic-mineral sediments in laboratory conditions and in the real conditions of operating single-bucket dredger in the Black Sea at the depth of 1885 m were carried out. The technique for calculation of the bucket\'s parameters was developed.
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Surface Conductance of Five Different Crops Based on 10 Years of Eddy-Covariance MeasurementsSpank, Uwe, Köstner, Barbara, Moderow, Uta, Grünwald, Thomas, Bernhofer, Christian 16 January 2017 (has links)
The Penman-Monteith (PM) equation is a state-of-the-art modelling approach to simulate evapotranspiration (ET) at site and local scale. However, its practical application is often restricted by the availability and quality of required parameters. One of these parameters is the canopy conductance. Long term measurements of evapotranspiration by the eddy-covariance method provide an improved data basis to determine this parameter by inverse modelling. Because this approach may also include evaporation from the soil, not only the ‘actual’ canopy conductance but the whole surface conductance (gc) is addressed. Two full cycles of crop rotation with five different crop types (winter barley, winter rape seed, winter wheat, silage maize, and spring barley) have been continuously monitored for 10 years. These data form the basis for this study. As estimates of gc are obtained on basis of measurements, we investigated the impact of measurements uncertainties on obtained values of gc. Here, two different foci were inspected more in detail. Firstly, the effect of the energy balance closure gap (EBCG) on obtained values of gc was analysed. Secondly, the common hydrological practice to use vegetation height (hc) to determine the period of highest plant activity (i.e., times with maximum gc concerning CO2-exchange and transpiration) was critically reviewed. The results showed that hc and gc do only agree at the beginning of the growing season but increasingly differ during the rest of the growing season. Thus, the utilisation of hc as a proxy to assess maximum gc (gc,max) can lead to inaccurate estimates of gc,max which in turn can cause serious shortcomings in simulated ET. The light use efficiency (LUE) is superior to hc as a proxy to determine periods with maximum gc. Based on this proxy, crop specific estimates of gc,maxcould be determined for the first (and the second) cycle of crop rotation: winter barley, 19.2 mm s−1 (16.0 mm s−1); winter rape seed, 12.3 mm s−1 (13.1 mm s−1); winter wheat, 16.5 mm s−1 (11.2 mm s−1); silage maize, 7.4 mm s−1 (8.5 mm s−1); and spring barley, 7.0 mm s−1 (6.2 mm s−1).
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Obosnovanie parametrov kovšej zemlečerpatel'nych snarjadov dlja glubokovodnoj dobyči organo-mineral'nych osadkovShepel, Taras 21 April 2015 (has links)
The thesis is devoted to determining the parameters of the bucket to increase productivity of dredgers while mining deep-water organic-mineral sediments. It was achieved by increasing the fill factor through determining the rational geometrical parameters of the bucket. Analytical dependencies of the rational height and length of the bucket on the cutting parameters and physical-and-mechanical properties of the excavated sediments were determined. Expressions for defining forces while digging plasticity water-saturated soils were developed. Experimental investigations of the process of digging deep-water organic-mineral sediments in laboratory conditions and in the real conditions of operating single-bucket dredger in the Black Sea at the depth of 1885 m were carried out. The technique for calculation of the bucket\'s parameters was developed.
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Zakládání na objemově nestálých zeminách / Foundations in Volume Unstable SoilsLegut, Dana Unknown Date (has links)
This dissertation is concerned with the foundations in volume unstable soils and objects disorders which are related to this. The thesis was focused on the study of clay and loess soils which are abundant in the geological profile of the Czech Republic. First, the formation of the two groups of soils is introduced, then their properties are examined and finally the influence of vegetation on the former type and the influence of collapsibility in the latter type are investigated. The conclusion is, in fact, a recommendation on the design of structures so that the system of clay / structure is not damaged and that structures are not subject to renovations. Several instance of problems with structures are discussed which were subject to structural repairs employing both a civil and geotechnical engineers.
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