34 results on '"Hydrological properties"'
Search Results
2. Reproductive and morphometric traits of freshwater mussel Lamellidens marginalis and associated hydrology in the Ratargul freshwater Swamp Forest, Bangladesh
- Author
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Mohammad Amzad Hossain, Monayem Hussain, Tumpa Rani Sarker, Shuvo Saha, and Mohammed Mahbub Iqbal
- Subjects
Sex ratio ,Condition indices ,Hydrological properties ,Morphometric traits ,Gonadal histology ,Aquaculture. Fisheries. Angling ,SH1-691 ,Environmental sciences ,GE1-350 - Abstract
A total of 300 freshwater mussels Lamellidens marginalis were sampled from the Ratargul Freshwater Swamp between December 2020 and November 2021 to investigate the relationships between length, weight, soft tissue wet parameters, sex ratio, condition indices, gonadal histology, and hydrological features of swamp forest habitat. The shell length and shell weight varied between 5.00 and 9.50 cm and 12.26–78.96 g respectively. The length at maturity Lm was recorded as 5.98 cm and the calculated value of χ2 suggested a dominant female stock at the study site (P
- Published
- 2023
- Full Text
- View/download PDF
3. Reproductive and morphometric traits of freshwater mussel Lamellidens marginalis and associated hydrology in the Ratargul freshwater Swamp Forest, Bangladesh.
- Author
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Hossain, Mohammad Amzad, Hussain, Monayem, Sarker, Tumpa Rani, Saha, Shuvo, and Iqbal, Mohammed Mahbub
- Abstract
A total of 300 freshwater mussels Lamellidens marginalis were sampled from the Ratargul Freshwater Swamp between December 2020 and November 2021 to investigate the relationships between length, weight, soft tissue wet parameters, sex ratio, condition indices, gonadal histology, and hydrological features of swamp forest habitat. The shell length and shell weight varied between 5.00 and 9.50 cm and 12.26–78.96 g respectively. The length at maturity L m was recorded as 5.98 cm and the calculated value of χ
2 suggested a dominant female stock at the study site (P < 0.05). The relationship between different morphometrics of Lamellidens marginalis and environmental parameters exhibits a very weak regression coefficient value (P < 0.05), suggesting a weak effect of seasonality on the growth metrics. Previtellogenic and vitellogenic oocytes were observed in the ovary, and mature spermatids were found in the testes in samples collected in the rainy season. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
4. Hydrological Properties of Soil and Litter Layers of Four Forest Types Restored in the Gully Erosion Area of Latosol in South China.
- Author
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Tu, Zhihua, Chen, Suyi, Chen, Zexian, Ruan, Dongshuo, Zhang, Wei, Han, Yujie, Han, Lin, Wang, Kang, Huang, Yanping, and Chen, Jinhui
- Subjects
EROSION ,SOIL erosion ,SOIL conservation ,FOREST restoration ,WATER conservation - Abstract
Litter and soil play an important role in influencing hydrological processes and the global water cycle. Artificial afforestation, as a part of vegetation restoration, was constructed in the gully erosion areas of latosol with the objective to prevent erosion. Variations in the hydrological properties in soils that have undergone vegetation restoration from gully erosion are not well understood. In this study, we examine the variations in the litter thickness and mass, soil structure and porosity, and hydrological properties of four forest types (eucalyptus–grass forest, bamboo–grass forest, acacia–grass forest, and shrub–grass forest). The results show that the total litter thickness varied from 1.71 to 3.74 cm and was highest in the acacia–grass forest. The total litter mass for the acacia–grass forest, 3.49 ± 0.06 t·ha
−1 , was significantly higher than that for the other forest types. The mass of the undecomposed litter (UL) layer was significantly lower than that of the semi-decomposed litter (SL). (2) The maximum water-retention capacity (Wmax ) and effective water-retention capacity (Weff ) of the SL layer were greater than those of the UL layer. The Wmax and Weff for the acacia–grass forest were markedly larger than those of the eucalyptus–grass, bamboo–grass, and shrub–grass forests. The water absorption rates of the SL and UL layers were highest during the onset of the immersion experiment, declined exponentially with time, and declined rapidly in the first 2 h. (4) The soil bulk density ranged from 1.46 g·cm−3 to 1.54 g·cm−3 , and the total porosity ranged from 32.06% to 37.13%. The soil bulk density increased with the increasing soil depth, while the total porosity decreased gradually. The soil water-holding capacity of the soil layer of 0–60 cm in the acacia–grass forest (301.76 t·ha−1 ) was greater than that of the other forest types. A comprehensive evaluation of the water conservation capacity by the entropy weight method showed that the water conservation capacity was greatest in the acacia–grass forest. The higher water-holding capacity of the acacia–grass forest may be more effective in enhancing rainfall interception, minimizing splash erosion, and decreasing surface runoff. Here, the results indicate that acacia–grass forest restoration can mitigate soil erosion by favoring soil and water conservation, improving the environment in the gully erosion area of latosol. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
5. Differential Hydrological Properties of Forest Litter Layers in Artificial Afforestation of Eroded Areas of Latosol in China.
- Author
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Tu, Zhihua, Chen, Suyi, Ruan, Dongshuo, Chen, Zexian, Huang, Yanping, and Chen, Jinhui
- Abstract
Litter is one of the key components of the forest ecosystem and plays a role as the second active layer influencing hydrological processes, which has affected the global water cycle. Soil- and water-conservation forests were constructed by artificial afforestation as a part of vegetation restoration in the eroded area of Latosol, and little is known about the differences in the hydrological properties of vegetation restoration in the eroded area of Latosol in the tropical region. We investigated the litter thickness, mass, and hydrological properties in three soil- and water-conservation forests (Eucalyptus robusta, Hevea brasiliensis, and Acacia mangium) through in situ surveys and laboratory experiments. The results showed that (1) the total litter thickness varied from 2.16 to 5.53 cm and was highest in the A. mangium forest. The total litter mass for A. mangium, 14.66 ± 1.09 t·ha
−1 , was significantly higher than that for E. robusta (5.45 ± 0.59 t·ha−1 ) and H. brasiliensis (3.01 ± 0.14 t·ha−1 ). The mass of the semi-decomposed litter (SDL) layer was markedly higher than that of the un-decomposed litter (UDL) layer. (2) The maximum water-retention capacity (Wmax ) and effective water-retention capacity (Weff ) of the SDL layer were larger than the UDL layer for three forest plantations. The Wmax and Weff for the A. mangium stand were significantly higher than those for the E. robusta and H. brasiliensis stand. (3) The water-absorption rate of the SDL and UDL layer were highest at the onset of the immersion experiment, declined exponentially with time, and especially declined rapidly in the first 2 h. A higher water-holding capacity of A. mangium may be more effective in enhancing rainfall interception, minimizing splash erosion, and decreasing surface runoff. These results indicate that planting A. mangium in E. robusta and H. brasiliensis forests and then turning them into mixed forests should improve soil and water conservation and maximize their ecological benefits. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
- View/download PDF
6. Effect of mineral and edible vegetable oils on physico-chemical and hydrological properties of sandy loam soils in parts of Nigerian basement complex.
- Author
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Ganiyu, Saheed Adekunle, Olurin, Oluwaseun Tolutope, Atoyebi, Mary Kehinde, and Salawu, Abiodun Oluwatoyin
- Abstract
The source, chemical composition, and refining processes of mineral oil are contrasted with that of edible vegetable oil. This study assessed the impacts of mineral and plant-derived oils on physico-chemical and hydrological properties of Haplic Lixisol (HL) and Alfisol soils in granitic areas, southwest Nigeria. Twenty-four (24) cluster top soil samples at a depth of 0–20 cm were collected with the aid of soil auger from Odeda (HL) and Ibadan (Alfisol). A total of twenty-one experimental pots filled with collected soils were set up with three replications using seven treatments: (1) petrol at 50 ml, (2) petrol at 100 ml, (3) diesel at 50 ml, (4) diesel at 100 ml, (5) palm oil at 50 ml, (6) palm oil at 100 ml, and (7) an untreated control. The soil physical and hydrological parameters were determined after 30 days to allow for interaction of the contaminants with the soils. Analysis of variance (ANOVA) and Pearson's correlation were used on the soil data in order to study the variation of analyzed soil characteristics under the two soil types and treatments as well as the relationship between the studied parameters, respectively. The regression analysis was used to generate models for the prediction of moisture content (MC) at selected suction levels. The obtained soil data showed that treatment with either selected petroleum hydrocarbon or vegetable oil had no noticeable impacts on soil pH and textural class. Results of soil treatments further revealed that palm oil contamination at 50 ml recorded least saturated hydraulic conductivity (K
sat ) values relative to control value in each sampling location. Furthermore, the Ksat values in treated HL soils at selected volumes were reduced compared to its control value while Ksat increased over control value in Alfisol soils treated with petrol. Correlation analysis showed strong negative correlation between soil resistivity (SR) and organic matter (OM) at 1% level in both soil types. Two-way ANOVA showed that there were significant differences at 5% level between the two locations with respect to bulk density (BD), total porosity (TP) and soil pH while significant differences in soil pH and % OM occur between soils from the two locations under different treatments at 5% level. There was no significant difference in the MC values at the different suction levels between the two locations and among the various treatments at 5% (p < 0.05) level. The regression analysis shows that all the generated models for predicting MC values at different suction levels under different soil treatments had R-square (R2 ) values ranging from 33.4 to 100% with significant F-values. The study recommends further investigation on impacts of more organic hydrocarbons and vegetable oils on soil quality properties. [ABSTRACT FROM AUTHOR]- Published
- 2021
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- View/download PDF
7. On the Circulation and Thermohaline Properties of the Eastern Mediterranean Sea
- Author
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Milena Menna, Riccardo Gerin, Giulio Notarstefano, Elena Mauri, Antonio Bussani, Massimo Pacciaroni, and Pierre-Marie Poulain
- Subjects
sub-basin anticyclones ,surface dynamics ,hydrological properties ,vertical mixing ,Eastern Mediterranean ,Science ,General. Including nature conservation, geographical distribution ,QH1-199.5 - Abstract
The circulation of the Eastern Mediterranean Sea is characterized by numerous recurrent or permanent anticyclonic structures, which modulate the pathway of the main currents and the exchange of the water masses in the basin. This work aims to describe the main circulation structures and thermohaline properties of the Eastern Mediterranean with particular focus on two anticyclones, the Pelops and the Cyprus gyres, using in-situ (drifters and Argo floats) and satellite (altimetry) data. The Pelops gyre is involved in the circulation and exchange of Levantine origin surface and intermediate waters and in their flow toward the Ionian and the Adriatic Sea. The Cyprus Gyre presents a marked interannual variability related to the presence/absence of waters of Atlantic origin in its interior. These anticyclones are characterized by double diffusive instability and winter mixing phenomena driven by salty surface waters of Levantine origin. Conditions for the salt finger regime occur steadily and dominantly within the Eastern Mediterranean anticyclones. The winter mixing is usually observed in December–January, characterized by instability conditions in the water column, a gradual deepening of the mixed layer depth and the consequent downward doming of the isohalines. The mixing generally involves the first 200 m of the water column (but occasionally can affect also the intermediate layer) forming a water mass with well-defined thermohaline characteristics. Conditions for salt fingers also occur during mixing events in the layer below the mixed layer.
- Published
- 2021
- Full Text
- View/download PDF
8. Hydrological properties of litter layers in mixed forests in Mt. Qinling, China
- Author
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Chen S, Cao T, Tanaka N, Gao T, Zhu L, and Zou CB
- Subjects
Water Conservation Forest ,Hydrological Properties ,Forest Succession ,Forestry ,SD1-669.5 - Abstract
The litter layer is an important component of forest ecosystems, although little is known about the differences in litter characteristics and hydrological properties of unmanaged, overgrown broadleaved and coniferous mixed forests in the subtropical and temperate zones. This study was carried out in a naturally generated broadleaved and coniferous mixed forest at the Qinling National Forest Ecosystem Research Station, Shaanxi Province, China. We quantified the litter thickness, mass, and its hydrological properties in evergreen pine (Pinus tabulaeformis) stands and deciduous oak (Quercus aliena var. acuteserrata) stands through in situ surveys and laboratory immersion experiments. The thickness of the litter layer for P. tabulaeformis averaged 9.3 ± 2.8 cm, and it was not significantly different from that detected in the Q. aliena stand (8.3 ± 3.6 cm). The total mass of the litter layer for P. tabulaeformis, 27.94 ± 9.81 Mg ha-1, was significantly higher than the total mass of 16.04 ± 3.60 Mg ha-1 found for Q. aliena. The mass of the semi-decomposed, fermented litter (OF) layer was significantly higher than that of the non-decomposed litter (OL) layer, irrespective of species. The rate of water absorption by dry litter was the highest at the onset of the immersion experiment and decreased exponentially with time. The water-holding capacity (Wm) and water-interception capacity (Wi) of the OF layer were higher than the OL layer for both forest stands. The Wm and Wi for the P. tabulaeformis stand were higher than those for the Q. aliena stand at our study sites. The higher Wm and Wi for P. tabulaeformis may be more effective in ameliorating the splash impact from high-intensity storms to improve water quality, while relatively lower Wm and Wi for Q. aliena may be considered favorable for augmenting water yield. Forest resource managers should consider those differences along with the other components of the water budget when making management decisions.
- Published
- 2018
- Full Text
- View/download PDF
9. Construction materials affect the hydrological properties of bird nests.
- Author
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Biddle, L. E., Dickinson, A. M., Broughton, R. E., Gray, L. A., Bennett, S. L., Goodman, A. M., and Deeming, D. C.
- Subjects
- *
BIRD nests , *CONSTRUCTION materials , *NEST building , *EGG incubation , *BIRD eggs , *WEATHER , *THERMAL insulation - Abstract
Bird nests are highly variable structures that represent extended phenotypes, which may have a range of roles during avian reproduction, but all nests serve as the location for incubation of eggs. Nest characteristics should counter any adverse weather conditions that could potentially reduce hatchability or chick survival. Thermal properties of nests are relatively well studied, but the effects of moisture on nest insulation are largely unknown. Wet nests could reduce thermal insulation or deleteriously cool the eggs or nestlings. In this study, a novel method of simulated rainfall was applied to open‐cup nests from nineteen different passerine species. The amount of water absorbed by the nest and the time it took to dry were recorded. To determine the factors affecting these characteristics, nests were deconstructed to provide data on materials used. Compared with smaller nests, larger nests absorbed more water and took longer to dry. The amount of water absorbed was a function of the proportion of grass, moss, roots and hair present in the nest. The time taken for the nest to dry completely was affected by the proportion of grass, moss, and hair in the nest. When tested individually, the materials all had different rates of water absorption and took different times to dry; moss absorbed the most water and took the longest time to dry. We concluded that simulated rainfall was a realistic approach to understanding the hydrological characteristics of nests. Structural considerations for nest construction may affect the hydrological properties of nests, but ex situ studies provide no information about the possible shelter provided to a nest by its immediate surroundings. Further research into nest function should consider the importance of exposure to water to nest construction and function. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
10. Differential Hydrological Properties of Forest Litter Layers in Artificial Afforestation of Eroded Areas of Latosol in China
- Author
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Zhihua Tu, Suyi Chen, Dongshuo Ruan, Zexian Chen, Yanping Huang, and Jinhui Chen
- Subjects
Renewable Energy, Sustainability and the Environment ,Geography, Planning and Development ,Building and Construction ,Management, Monitoring, Policy and Law ,soil- and water-conservation forest ,Mahuangling Watershed ,hydrological properties ,litter layer - Abstract
Litter is one of the key components of the forest ecosystem and plays a role as the second active layer influencing hydrological processes, which has affected the global water cycle. Soil- and water-conservation forests were constructed by artificial afforestation as a part of vegetation restoration in the eroded area of Latosol, and little is known about the differences in the hydrological properties of vegetation restoration in the eroded area of Latosol in the tropical region. We investigated the litter thickness, mass, and hydrological properties in three soil- and water-conservation forests (Eucalyptus robusta, Hevea brasiliensis, and Acacia mangium) through in situ surveys and laboratory experiments. The results showed that (1) the total litter thickness varied from 2.16 to 5.53 cm and was highest in the A. mangium forest. The total litter mass for A. mangium, 14.66 ± 1.09 t·ha−1, was significantly higher than that for E. robusta (5.45 ± 0.59 t·ha−1) and H. brasiliensis (3.01 ± 0.14 t·ha−1). The mass of the semi-decomposed litter (SDL) layer was markedly higher than that of the un-decomposed litter (UDL) layer. (2) The maximum water-retention capacity (Wmax) and effective water-retention capacity (Weff) of the SDL layer were larger than the UDL layer for three forest plantations. The Wmax and Weff for the A. mangium stand were significantly higher than those for the E. robusta and H. brasiliensis stand. (3) The water-absorption rate of the SDL and UDL layer were highest at the onset of the immersion experiment, declined exponentially with time, and especially declined rapidly in the first 2 h. A higher water-holding capacity of A. mangium may be more effective in enhancing rainfall interception, minimizing splash erosion, and decreasing surface runoff. These results indicate that planting A. mangium in E. robusta and H. brasiliensis forests and then turning them into mixed forests should improve soil and water conservation and maximize their ecological benefits.
- Published
- 2022
- Full Text
- View/download PDF
11. Tomography of Soil Pores: from Morphological Characteristics to Structural–Functional Assessment of Pore Space.
- Author
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Ivanov, A. L., Shein, E. V., and Skvortsova, E. B.
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SOIL science , *TECHNOLOGY , *SOIL structure , *SOILS , *SOIL degradation , *SOIL testing - Abstract
The development of tomographic studies of soil pore space in Russian soil science in 2011–2018 is discussed. In several years, these studies have evolved from the qualitative description of pores in some soils from the European part of Russia to the quantitative functional assessment of soil pore space on the bases of 3D tomographic models. Three stages of tomographic studies of soil pores can be distinguished: (1) qualitative analysis of pore space as a spatial-geometric characteristic of soil structure and as a component of the general analysis of soil morphology; (2) the obtaining of quantitative morphometric data on the shape, size, and orientation of soil pores and combined analysis of these tomographic data and data on the physical soil properties; and (3) the use of calculated tomographic parameters in the study of hydrological and physicomechanical properties of soils important for both theoretical and applied aspects of soil science. In recent years, the research has been focused on the assessment of the relationships between tomographic parameters of soil pore space and traditional soil hydrological constants, possibility of calculating the water retention curve and water conductivity function from the tomographic parameters of soil pore space, and on the quantitative assessment and prediction of soil degradation on the basis of tomographic data. The solution to these problems will make it possible to explain the physical phenomena controlling soil hydrological characteristics and to substantiate the use of tomographic data in applied soil science, soil hydrology, and agrophysics. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
12. Biochar implications for the engineering properties of soils: A review.
- Author
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Lu, Yu, Gu, Kai, Shen, Zhengtao, Tang, Chao-Sheng, Shi, Bin, and Zhou, Qiyou
- Published
- 2023
- Full Text
- View/download PDF
13. The size of clearings for charcoal production in miombo woodlands affects soil hydrological properties and soil organic carbon.
- Author
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Lulandala, L., Bargués-Tobella, A., Masao, C.A., Nyberg, G., and Ilstedt, U.
- Subjects
CHARCOAL ,SOIL infiltration ,FOREST soils ,FORESTS & forestry ,CARBON in soils ,WATER supply ,FOREST management - Abstract
• Charcoal production in miombo woodlands negatively affect soil hydrological properties and soil organic carbon. • Large clearings for charcoal production are more detrimental than smaller clearings. • Small clearings showed higher infiltration capacity and soil organic carbon. • Soil infiltration capacity increased with increasing tree basal area. • Control of livestock grazing could minimize the impact of forest disturbance by charcoal production. Charcoal production is a major driver of forest degradation in miombo woodlands. Forests play a crucial role in regulating the hydrological cycle, so it is critical to understand how forest degradation and management practices impact water availability, particularly in drylands. Few studies have examined the effect of forest clearing size on the hydrological functioning of soil, particularly under real-world conditions where, following clearing, forests are subject to multiple and prolonged anthropogenic disturbances, as occurs in miombo woodlands which are cleared for charcoal production and commonly used for livestock grazing. The pilot project Transforming Tanzania's Charcoal Sector was established in 2012 with the aim of establishing a sustainable wood harvesting system for charcoal production based on rotational harvesting cycles that allow for natural forest regeneration. Two clearing sizes were established: large clearings (300 × 300 m) harvested by clear-felling, and small clearings (50 × 50 m) harvested in a checkerboard pattern. We examined the effect of these two clearing sizes on soil hydrological properties and soil organic carbon (SOC) in Kilosa district, Morogoro, Tanzania. Our analysis included four treatments: large clearings, small clearings, small intact plots (unharvested plots within the checkboard pattern), and village land forest reserve. For each treatment we assessed the tree cover and measured soil infiltration capacity, soil bulk density, SOC stock, and texture. We also examined the relationship between these variables and the distance to the closest road to better understand the impact of livestock and human disturbance. Our results show that large clearings had the lowest mean infiltration capacity (121 ± 3 mm h
−1 ) and SOC stock content (12 ± 0.2 tonnes ha−1 ), and the highest bulk density (1.6 ± 0.005 g cm−3 ) of all the treatments. We found a positive relationship between infiltration capacity and basal area (R2 = 0.71) across all treatments. We also found that infiltration capacity, SOC stock and tree basal area increased with increasing distance from the closest road, while bulk density decreased. We conclude that, in terms of their impact on soil hydrological functioning and SOC stock, small clearings, while not completely unaffected, are better than larger ones. In small clearings, concurrent reductions in tree cover and a relatively low impact on soil hydrological properties could result in increased soil and groundwater recharge compared to unharvested forest areas. Controlling livestock grazing can further minimize soil degradation, producing additional gains. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
14. Impact of a thermokarst lake on the soil hydrological properties in permafrost regions of the Qinghai-Tibet Plateau, China.
- Author
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Gao, Zeyong, Niu, Fujun, Wang, Yibo, Luo, Jing, and Lin, Zhanju
- Subjects
- *
THERMOKARST , *HYDROLOGY , *SOIL moisture , *ENVIRONMENTAL impact analysis , *PERMAFROST , *ECOSYSTEMS - Abstract
The formation of thermokarst lakes can degrade alpine meadow ecosystems through changes in soil water and heat properties, which might have an effect on the regional surface water and groundwater processes. In this study, a typical thermokarst lake was selected in the Qinghai-Tibet Plateau (QTP), and the ecological index (S L ) was used to divide the affected areas into extremely affected, severely affected, medium-affected, lightly affected, and non-affected areas, and soil hydrological properties, including saturated hydraulic conductivity and soil water-holding capacity, were investigated. The results showed that the formation of a thermokarst lake can lead to the degradation of alpine meadows, accompanied by a change in the soil physiochemical and hydrological properties. Specifically, the soil structure turned towards loose soil and the soil nutrients decreased from non-affected areas to severely affected areas, but the soil organic matter and available potassium increased slightly in the extremely affected areas. Soil saturated hydraulic conductivity showed a 1.7- to 4.1-fold increase in the lake-surrounding areas, and the highest value (401.9 cm d − 1 ) was detected in the severely affected area. Soil water-holding capacity decreased gradually during the transition from the non-affected areas to the severely affected areas, but it increased slightly in the extremely affected areas. The principal component analysis showed that the plant biomass was vital to the changes in soil hydrological properties. Thus, the vegetation might serve as a link between the thermokarst lake and soil hydrological properties. In this particular case, it was concluded that the thermokarst lake adversely affected the regional hydrological services in the alpine ecosystem. These results would be useful for describing appropriate hydraulic parameters with the purpose of modeling soil water transportation more accurately in the Qinghai-Tibet Plateau. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
15. On the Circulation and Thermohaline Properties of the Eastern Mediterranean Sea
- Author
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Riccardo Gerin, Massimo Pacciaroni, Giulio Notarstefano, Elena Mauri, Milena Menna, Antonio Bussani, and Pierre-Marie Poulain
- Subjects
Water mass ,sub-basin anticyclones ,010504 meteorology & atmospheric sciences ,Mixed layer ,Eastern Mediterranean ,Science ,Doming ,Ocean Engineering ,Aquatic Science ,QH1-199.5 ,Oceanography ,01 natural sciences ,Water column ,vertical mixing ,Ocean gyre ,surface dynamics ,Argo ,0105 earth and related environmental sciences ,Water Science and Technology ,Global and Planetary Change ,geography ,geography.geographical_feature_category ,010505 oceanography ,hydrological properties ,General. Including nature conservation, geographical distribution ,Anticyclone ,Thermohaline circulation ,Geology - Abstract
The circulation of the Eastern Mediterranean Sea is characterized by numerous recurrent or permanent anticyclonic structures, which modulate the pathway of the main currents and the exchange of the water masses in the basin. This work aims to describe the main circulation structures and thermohaline properties of the Eastern Mediterranean with particular focus on two anticyclones, the Pelops and the Cyprus gyres, using in-situ (drifters and Argo floats) and satellite (altimetry) data. The Pelops gyre is involved in the circulation and exchange of Levantine origin surface and intermediate waters and in their flow toward the Ionian and the Adriatic Sea. The Cyprus Gyre presents a marked interannual variability related to the presence/absence of waters of Atlantic origin in its interior. These anticyclones are characterized by double diffusive instability and winter mixing phenomena driven by salty surface waters of Levantine origin. Conditions for the salt finger regime occur steadily and dominantly within the Eastern Mediterranean anticyclones. The winter mixing is usually observed in December–January, characterized by instability conditions in the water column, a gradual deepening of the mixed layer depth and the consequent downward doming of the isohalines. The mixing generally involves the first 200 m of the water column (but occasionally can affect also the intermediate layer) forming a water mass with well-defined thermohaline characteristics. Conditions for salt fingers also occur during mixing events in the layer below the mixed layer.
- Published
- 2021
- Full Text
- View/download PDF
16. Stability and Hydrological Modifications in a Tilled Soil under Selected Organic Amendments in South-Eastern Nigeria.
- Author
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AHAMEFULE, HENRY EMEKA, NWOKOCHA, CHRIS CHUKWUMA, and AMANA, SANNI MATHEW
- Subjects
- *
TILLAGE , *HYDROLOGY , *ULTISOLS , *SOIL stabilization , *SOIL structure - Abstract
A 36 months study was carried out in Nsukka, south-eastern Nigeria to determine the effect of organic amendment on the stability and hydrological properties of a tilled fragile Ultisol. The experiment was of a Randomized Complete Block Design (RCBD) with three (3) organic amendments and a control replicated thrice. The soil amendments were comprised of Palm Oil Mill Effluent (PE), Palm Bunch Refuse (PR), Cassava Peels (CS) at 12 Mg/ha and No Amendment/control (NA). Results indicated that organic amendment of tilled plots significantly increased the stability of wet and dry soil aggregates compared to soil aggregates in unamended plots. The amendment of tilled soils led to increased saturated hydraulic conductivity, water sorptivity, transmissivity, steady-state infiltration rate, cumulative infiltration after 90 minutes, time to attain steady-state infiltration and water retention. However, the general trend shows that highest values were obtained when soils were under PE and CS amendments, with values in PE treated soils showing relative increment of more than 100 % compared to control. [ABSTRACT FROM AUTHOR]
- Published
- 2015
17. The influence of Caragana korshinskii shrub on soil and hydrological properties in a revegetation-stabilized desert ecosystem.
- Author
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Pan, Yan-Xia, Wang, Xin-Ping, Li, Xin-Rong, Zhang, Ya-Feng, Hu, Rui, and Zhang, Hao
- Subjects
- *
CARAGANA , *SHRUBS , *ARID soils , *SOIL moisture , *SOIL chemistry , *SOIL infiltration , *SOIL composition - Abstract
Shrub-induced spatial heterogeneity of soil and hydrological properties are common in arid and semi-arid ecosystems. To examine the influence of shrubs on spatial patterns of soil physical, chemical and hydrological properties, the typical sand-fixation species,Caragana korshinskii, was studied in the Shapotou area of the Tengger Desert, China. Miniature cylinder infiltrometers were used to quantify the spatial variations of infiltration rate in the soils, and were installed at 20-cm intervals around the shrubs. Meanwhile, soil samples were collected at 0–5 cm depth every 10 cm to analyse their physical and chemical properties and soil moisture content. The results indicate that the various measured parameters showed a gradational change from sub-canopy to open space. The establishment of shrubs formed obvious “fertile islands” where more soil nutrients collected. The total nitrogen (TN), soil organic matter (SOM), electrical conductivity (EC) and surface soil moisture content decreased gradually from around shrub stems to the interspace. The sand content around shrub stems was significantly higher (p < 0.05), and decreased gradually from the centre towards the outside microsites. The silt and clay contents showed opposite variability characteristics. The variation of soil bulk density was less within 140 cm distance from the stem, and no abrupt change was found at the shrub’s drip line. No significant tendency was found for the soil pH values. The steady infiltration rates declined with increasing stem distance and then tended to be stable, and no abrupt change occurred at the position of the overhead canopy margin. The increase of infiltration rate was rapid nearer to the stem; the variability trend can be fitted by a log-log (power function) model. This study indicated the gradational change in soil and hydrological properties, which was not consistent with the binary division of shrubs into “canopy” and “interspace” zones.Editor Z.W. Kundzewicz [ABSTRACT FROM PUBLISHER]
- Published
- 2014
- Full Text
- View/download PDF
18. Toprak hidropedolojik özelliklerinin gypsic ustorthent ve typic ustifluent’de faktör analizi ile değerlendirilmesi
- Author
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Gülay Karahan
- Subjects
hidropedoloji ,morfolojik özellikler ,Factor analysis,Hydrological properties,Hydropedology,Morphological properties,Soil mechanics ,Fen ,hydrological properties ,Science ,lcsh:S ,factor analysis ,faktör analizi ,lcsh:S1-972 ,hydropedology ,toprak mekaniği ,lcsh:Agriculture ,Faktör analizi,Hidrolojik özellikler,Hidropedoloji,Morfolojik özellikler,Toprak mekaniği ,morphological properties ,soil mechanics ,lcsh:Agriculture (General) ,hidrolojik özellikler - Abstract
This study was conducted to evaluate soil morphological and hydrologic variables by factor analysis in a paddy field (Gypsic Ustorthent) and grassland (Typic Ustifluvents) in Kızılırmak county of Çankırı province in central Anatolia of Turkey. Fifty undisturbed soil samples were taken from the paddy field and seventy from the grassland with plastic soil samplers. Disturbed soil samples were taken from the same points for basic soil analyses. Saturated hydraulic conductivity (Ks) was measured on soil columns using a hydraulic conductivity set with a constant-head permeameter. Following the Ks measurements, soil columns were covered to prevent evaporation. When the water flow through the columns was stopped, samplings were taken for bulk density and penetration resistance was measured. Then the soils were removed, the morphological properties were defined and quantified with the help of standard soil description charts. Soil parametric and morphological properties were evaluated by factor analysis. Five factors (Hydropedology, Silt and soil chemistry, Root, pH and mottles, Aggregation) described 80.00% of the total variation in the paddy soils and six factors (Hydropedology, Silt and soil chemistry, Root, pH and mottles, Color and soil chemistry, Aggregation) defined 84.41% of the total variation in the grassland soils. The use of soil morphological variables along with parametric variables was found promising in understanding interlinkages between pedology and hydrology., Bu çalışma, Orta Anadolu'nun Çankırı ili Kızılırmak ilçesinde bulunan bir çeltik tarlasında (Typic Ustifluvent) ve mera alanında (Gypsic Ustorthent) toprak morfolojik ve hidrolojik değişkenlerini faktör analizi ile değerlendirmek amacıyla yapılmıştır. Plastik toprak örnekleyicileri ile çeltik tarlasından 50, mera alanından 70 adet bozulmamış toprak örneği alınmıştır. Temel toprak analizleri için aynı noktalardan bozulmuş toprak örnekleri alınmıştır. Doymuş hidrolik iletkenlik (Ks), toprak kolonlarında sabit yük seviyeli bir hidrolik iletkenlik seti kullanılarak ölçülmüştür. Ks ölçümünü takiben, buharlaşmayı önlemek için toprak kolonlarının üstü kapatılmıştır. Kolonlardan su akışı durduğunda, hacim ağırlığı için örnekler alınmış ve penetrasyon direnci ölçülmüştür. Sonra, topraklar çıkarılmış, toprak örneklerinin morfolojik özellikleri tanımlanarak standart toprak tanımlama çizelgeleri yardımıyla nicelendirilmiştir. Çeltik tarlası ve mera topraklarında toprak parametrik ve morfolojik özellikleri faktör analizi ile değerlendirilmiştir. Çeltik topraklardaki toplam varyasyonun %80’ini beş faktör (Hidropedoloji, Kök, Silt ve toprak kimyası, Toprak kimyası, Agregasyon) ve mera topraklarındaki toplam varyasyonun %84.41'ini altı faktör (Hidropedoloji, Kök, Silt ve toprak kimyası, Toprak kimyası, Renk ve toprak kimyası, Agregasyon) tanımlamıştır. Pedoloji ve hidroloji arasındaki bağlantıların anlaşılmasında parametrik değişkenlerle birlikte toprak morfolojik değişkenlerinin kullanılması umut verici bulunmuştur.
- Published
- 2020
19. Does biochar improve soil water retention? A systematic review and meta-analysis
- Author
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Emmanuel Arthur, Fatemeh Razzaghi, and Peter Bilson Obour
- Subjects
5-YEAR FIELD TRIAL ,STRUCTURAL-PROPERTIES ,Amendment ,Biochar characteristics ,Soil Science ,PHYSICAL-PROPERTIES ,010501 environmental sciences ,Soil water content ,01 natural sciences ,HYDROLOGICAL PROPERTIES ,Field capacity ,HYDRAULIC-PROPERTIES ,ORGANIC-CARBON ,DIFFERENT FEEDSTOCKS ,Biochar ,medicine ,PYROLYSIS TEMPERATURES ,Water content ,0105 earth and related environmental sciences ,Soil textural classes ,Experimental conditions ,SUGARCANE BAGASSE ,04 agricultural and veterinary sciences ,Bulk density ,Water retention ,Permanent wilting point ,Agronomy ,RICE-HUSK BIOCHAR ,Soil water ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Environmental science ,Biochar added carbon ,medicine.symptom - Abstract
Biochar is widely suggested as a soil amendment to improve soil physical properties for crop production. However, the heterogeneity between experiments in terms of biochar characteristics, experimental conditions and soil properties makes it difficult to compare and extrapolate results from different studies. We conducted a statistical meta-analysis of literature published between 2010 and 2019, and quantified biochar's impacts on soil bulk density (BD) and water retention variables, namely, soil water content held at field capacity (FC), wilting point (WP) and plant available water content (AW). Across all soil textural groups, biochar on average decreased BD by 9%. FC and WP significantly increased for the coarse-textured soils (by 51% and 47%, respectively), and moderately for the medium-textured soils (by 13% and 9%, respectively). For the fine-textured soils, FC remained unchanged (
- Published
- 2020
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- View/download PDF
20. Hydrological properties of litter layers in mixed forests in Mt. Qinling, China
- Author
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Tianjian Cao, Noriyoshi Tanaka, Tian Gao, Siyun Chen, Lun-qing Zhu, and Chris B. Zou
- Subjects
Forest Succession ,010504 meteorology & atmospheric sciences ,Hydrological Properties ,0208 environmental biotechnology ,02 engineering and technology ,01 natural sciences ,Forest ecology ,Temperate climate ,Ecosystem ,Water Conservation Forest ,lcsh:Forestry ,0105 earth and related environmental sciences ,Nature and Landscape Conservation ,Quercus aliena ,Ecology ,biology ,Forestry ,Evergreen ,biology.organism_classification ,020801 environmental engineering ,Deciduous ,Agronomy ,Litter ,Environmental science ,lcsh:SD1-669.5 ,Water quality - Abstract
The litter layer is an important component of forest ecosystems, although little is known about the differences in litter characteristics and hydrological properties of unmanaged, overgrown broadleaved and coniferous mixed forests in the subtropical and temperate zones. This study was carried out in a naturally generated broadleaved and coniferous mixed forest at the Qinling National Forest Ecosystem Research Station, Shaanxi Province, China. We quantified the litter thickness, mass, and its hydrological properties in evergreen pine (Pinus tabulaeformis) stands and deciduous oak (Quercus aliena var. acuteserrata) stands through in situ surveys and laboratory immersion experiments. The thickness of the litter layer for P. tabulaeformis averaged 9.3 ± 2.8 cm, and it was not significantly different from that detected in the Q. aliena stand (8.3 ± 3.6 cm). The total mass of the litter layer for P. tabulaeformis, 27.94 ± 9.81 Mg ha-1, was significantly higher than the total mass of 16.04 ± 3.60 Mg ha-1 found for Q. aliena. The mass of the semi-decomposed, fermented litter (OF) layer was significantly higher than that of the non-decomposed litter (OL) layer, irrespective of species. The rate of water absorption by dry litter was the highest at the onset of the immersion experiment and decreased exponentially with time. The water-holding capacity (Wm) and water-interception capacity (Wi) of the OF layer were higher than the OL layer for both forest stands. The Wm and Wi for the P. tabulaeformis stand were higher than those for the Q. aliena stand at our study sites. The higher Wm and Wi for P. tabulaeformis may be more effective in ameliorating the splash impact from high-intensity storms to improve water quality, while relatively lower Wm and Wi for Q. aliena may be considered favorable for augmenting water yield. Forest resource managers should consider those differences along with the other components of the water budget when making management decisions.
- Published
- 2018
21. PERMEABILITY OF ABEOKUTA RIVERBED SEDIMENTS.
- Author
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Akinyemi, Olukayode Dewumi, Adesegun, Bisola, and Akinpelu, Sunday
- Subjects
- *
RIVER channels , *RIVER sediments , *SEDIMENT permeability , *GROUNDWATER , *HYDRAULICS , *TUBES - Abstract
Determination of discharge capacity helps to predict the nature and extent of underground water flow. Riverbed sediments from Abeokuta, southwestern Nigeria, were studied in the laboratory to investigate rates of discharge using different dimensions of packed tubes inclined at varying angles of tilt. Discharge capacity increased with inclination angles, while maximum discharge capacities increased with lengths and diameters of tubes. Comparing volume rates of flow with inclination angles of flaw revealed unique convergence points at which the discharge capacity and angles of inclination remained constant irrespective of the samples. The discharge rate convergence point ranged from 0.3 × 10-1 to 0.5 × 10-9m3/s, while the angle of tilt convergence point ranged from 2.1° to 6.0°. Convergence points for the angle of tilt correlated strongly with the convergence points for the discharge capacity [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
22. Research on Litter Hydrological Properties of Inefficient Forest in Jinyun Mountain.
- Author
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Li, Yang, Rao, Liangyi, and Wang, Baitian
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LITTERS ,HYDROLOGY ,FORESTS & forestry ,MOUNTAINS ,WATER conservation ,FOREST reserves ,TAIGAS - Abstract
Abstract: The purpose of this paper is to transform inefficient water conservation forests in Jinyun Mountain, as well as provide a basis for inefficient forest transformation. In this paper, we get forest reserves, maximum water holding capacity, maximum water holding rate and some hydrological parameters of different forest litter types through the waterholding characteristics analysis of three kinds of litter in Jinyun Mountain. The litter reserve of standard plot one is 874.33g/m2, 980g/m2 in standard plot two, and 264.22g/m2 in standard plot three. The maximum water holding rate of undecomposed layer of standard plot one is 183.56%, 177.98% in standard plot two, and 219.49% in standard plot three. The maximum water holding rate of semi-decomposed layer of standard plot one is 246.08%, 106.08% in standard plot two, and 250.88% in standard plot three. The maximum water holding capacity of undecomposed layer of standard plot one is 684.68g/m2, 557.66g/m2 in standard plot two, and 180.23g/m2 in standard plot three. The maximum water holding capacity of semi-decomposed layer of standard plot one is 1167.23g/m2, 707.20g/m2 in standard plot two, and 456.88g/m2 in standard plot three. The results indicated that the maximum water holding capacity from high to low is standard plot one > standard plot two > standard plot three. The maximum water holding rate from high to low is standard plot three > standard plot one > standard plot two. The water holding capacity of coniferous and broadleaf mixed forest litter is more than coniferous mixed forest litter. It is further illustrates that the more complex stand structure, the more water holding capacity of litter will be. [Copyright &y& Elsevier]
- Published
- 2011
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- View/download PDF
23. Effects of Tractor Passes on Hydrological and Soil Erosion Processes in Tilled and Grassed Vineyards
- Author
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Giorgio Capello, Eugenio Cavallo, Marcella Biddoccu, and Stefano Ferraris
- Subjects
lcsh:Hydraulic engineering ,Geography, Planning and Development ,runoff ,010501 environmental sciences ,Aquatic Science ,01 natural sciences ,Biochemistry ,Vineyard ,Soil management ,vineyards ,lcsh:Water supply for domestic and industrial purposes ,Hydraulic conductivity ,lcsh:TC1-978 ,compaction ,tractor traffic ,0105 earth and related environmental sciences ,Water Science and Technology ,Erosion ,Hydrological properties ,Runoff ,Soil water conservation ,Tractor traffic ,Vineyards ,Hydrology ,lcsh:TD201-500 ,hydrological properties ,04 agricultural and veterinary sciences ,erosion ,Bulk density ,Tillage ,Soil water ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Environmental science ,Surface runoff ,soil management ,soil water conservation ,hydraulic conductivity - Abstract
Soil erosion is affected by rainfall temporal patterns and intensity variability. In vineyards, machine traffic is implemented with particular intensity from late spring to harvest, and it is responsible for soil compaction, which likely affects soil hydraulic properties, runoff, and soil erosion. Additionally, the hydraulic and physical properties of soil are highly influenced by vineyards&rsquo, inter-rows soil management. The effects on soil compaction and both hydrological and erosional processes of machine traffic were investigated on a sloping vineyard with different inter-row soil managements (tillage and permanent grass cover) in the Alto Monferrato area (Piedmont, NW Italy). During the investigation (November 2016&ndash, October 2018), soil water content, rainfall, runoff, and soil erosion were continuously monitored. Field-saturated hydraulic conductivity, soil penetration resistance, and bulk density were recorded periodically in portions of inter-rows affected and not affected by the machine traffic. Very different yearly precipitation characterized the observed period, leading to higher bulk density and lower infiltration rates in the wetter year, especially in the tilled vineyard, whereas soil penetration resistance was generally higher in the grassed plot and in drier conditions. In the wet year, management with grass cover considerably reduced runoff (&minus, 76%) and soil loss (&minus, 83%) compared to tillage and in the dry season. Those results highlight the need to limit the tractor traffic, in order to reduce negative effects due to soil compaction, especially in tilled inter-rows.
- Published
- 2019
- Full Text
- View/download PDF
24. Potential of developing podzolic soil-based potting media from wood ash, paper sludge and biochar.
- Author
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Farhain, Muhammad M., Cheema, Mumtaz, Katanda, Yeukai, Nadeem, Muhammad, Javed, Bilal, Thomas, Raymond, Saha, Ratnajit, and Galagedara, Lakshman
- Subjects
- *
WOOD ash , *POTTING soils , *ORGANIC wastes , *BIOCHAR , *PAPER mill waste , *PLANT-water relationships , *WASTE management - Abstract
Organic waste management in environmentally sustainable way is important not only to reduce the negative impacts on ecosystems but also valorizing the waste resources. Herein we evaluated the potential of wood ash (WA) and paper sludge (PS) wastes from a pulp and paper mill as potting media and their effects on the physicochemical properties of podzolic soil. WA, PS and biochar (BC) was mixed in different combinations with a sandy loam podzolic soil. Potting media treatments included: T1–soil (negative control); T2–PromixTM (positive control); T3–50%soil+50%WA; T4–75%soil+25%WA; T5–50%soil+50%PS; T6–75%soil+25%PS; T7–75%soil+25%BC; T8–25%soil+50%WA+25%BC; T9–50%soil+25%WA+25%BC; T10–25%soil+50%PS+25%BC; T11–50%soil+25%PS+25%BC, T12– 25%soil+25%WA+25%PS+25%BC and replicated three times. Potting media treatments expressed significant (p < 0.00) effects on pH, bulk density, total porosity, field capacity, plant available water (PAW) and water retention curves. Potting media amended with WA showed high pH range (8–12) while PS amendments exhibited pH in range where most plant nutrients are available (6.5–7.5). Results depicted significantly lower bulk density, and increased total porosity and water holding capacity of potting media amended with WA and PS. BC addition further enhanced the water retention properties compared to combinations without BC. T6, T10 and T11 produced higher amounts of PAW with desired pH compared to T1 and T2. WA, PS and BC showed high potential for developing podzolic soil-based potting media, but their effects on plant growth and elemental uptake need to be investigated. • Valorization of organic waste is important to improve environmental sustainability through recycling of valuable waste. • Herein we investigated the potential applications of wood ash and paper sludge as a potting media for horticultural crops. • Wood ash and paper sludge improved the physicochemical properties of podzolic soil. • Paper sludge was more effective than wood ash in improving soil hydrological properties for better plant growth. • Furthermore, the incorporation of biochar in the potting media enhanced water holding capacity. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
25. Intra- and inter-seasonal variations in the hydrological characteristics and nutrient conditions in the southwestern Yellow Sea during spring to summer.
- Author
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Wang, Junjie, Yu, Zhigang, Wei, Qinsheng, Yang, Fuxia, Dong, Mingfan, Li, Dandan, Gao, Zhimei, and Yao, Qingzhen
- Subjects
SUSTAINABLE development ,SEAWATER ,WATER masses ,SEAS ,SPRING - Abstract
Based on field survey in the southwestern Yellow Sea (SWYS) during April–September 2017, the spatiotemporal variations in the hydrological characteristics and nutrient conditions were coupled and analyzed; the intra-seasonal variations in the upwelling in the front of the Yellow Sea Cold Water Mass (YSCWM) and impacts on nutrient transport were explored. The coastal area was controlled by the low-salinity high-nutrient Lubei Coastal Current, Subei Coastal Current, and Yangtze River Diluted Water from north to south; at bottom, the northeastern SWYS was controlled by the low-temperature high-salinity high-nutrient YSCWM. Temperature, salinity and nutrient fronts formed around YSCWM. The upwelling velocity in the front increased during April to late June and decreased in early September; the upwelled fluxes of dissolved inorganic nitrogen (0.29×10
3 -7.77×103 μmol·m-2 d-1 ), phosphate (0.02×103 -0.27×103 μmol·m-2 d-1 ) and silicate (0.98×103 -8.75×103 μmol·m-2 d-1 ) showed similar variations during April–September. The upwelled nutrients could potentially contribute to local green tide development and phytoplankton growth during spring–summer. Unlabelled Image • Temperature, salinity and nutrient (NU) fronts form around Yellow Sea Cold Watermass. • Upwelling velocity & NU flux in the front increase during APR–JUN & decline in SEP. • Upwelled NUs may contribute to local green tide development and phytoplankton growth. [ABSTRACT FROM AUTHOR]- Published
- 2020
- Full Text
- View/download PDF
26. Effects of Tractor Passes on Hydrological and Soil Erosion Processes in Tilled and Grassed Vineyards.
- Author
-
Capello, Giorgio, Biddoccu, Marcella, Ferraris, Stefano, and Cavallo, Eugenio
- Subjects
SOIL infiltration ,SOIL moisture ,SOIL management ,SOIL compaction ,VINEYARDS ,HYDRAULIC conductivity ,TILLAGE ,TRACTORS - Abstract
Soil erosion is affected by rainfall temporal patterns and intensity variability. In vineyards, machine traffic is implemented with particular intensity from late spring to harvest, and it is responsible for soil compaction, which likely affects soil hydraulic properties, runoff, and soil erosion. Additionally, the hydraulic and physical properties of soil are highly influenced by vineyards' inter-rows soil management. The effects on soil compaction and both hydrological and erosional processes of machine traffic were investigated on a sloping vineyard with different inter-row soil managements (tillage and permanent grass cover) in the Alto Monferrato area (Piedmont, NW Italy). During the investigation (November 2016–October 2018), soil water content, rainfall, runoff, and soil erosion were continuously monitored. Field-saturated hydraulic conductivity, soil penetration resistance, and bulk density were recorded periodically in portions of inter-rows affected and not affected by the machine traffic. Very different yearly precipitation characterized the observed period, leading to higher bulk density and lower infiltration rates in the wetter year, especially in the tilled vineyard, whereas soil penetration resistance was generally higher in the grassed plot and in drier conditions. In the wet year, management with grass cover considerably reduced runoff (−76%) and soil loss (−83%) compared to tillage and in the dry season. Those results highlight the need to limit the tractor traffic, in order to reduce negative effects due to soil compaction, especially in tilled inter-rows. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
27. Constraining complex aquifer geometry with geophysics (2-D ERT and MRS measurements) for stochastic modelling of groundwater flow
- Author
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Laurent Ruiz, Marc Descloitres, Yves Goddéris, Muddu Sekhar, Abhijit Chaudhuri, Jean-Jacques Braun, Department of Applied Mechanics, Indian Institute of Technology Kanpur (IIT Kanpur), Department of Civil Engineering - Indo-French Cell for Water Science, Indian Institute of Science, Laboratoire d'étude des transferts en hydrologie et environnement (LTHE), Institut National Polytechnique de Grenoble (INPG)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Géosciences Environnement Toulouse (GET), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD), Sol Agro et hydrosystème Spatialisation (SAS), Institut National de la Recherche Agronomique (INRA)-AGROCAMPUS OUEST, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), Indo-French Cell for Water Sciences (IFCWS), Indian Institute of Science [Bangalore] (IISc Bangalore), NCP scheme of the All India Council for Technical Education, French national programme ORE-BVET, Embassy of France in India, Centre National de la Recherche Scientifique (CNRS)-Institut National Polytechnique de Grenoble (INPG)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut de Recherche pour le Développement (IRD)-Centre National d'Études Spatiales [Toulouse] (CNES), and Indo-French Cell for Water Science
- Subjects
010504 meteorology & atmospheric sciences ,Groundwater flow ,Stochastic modelling ,[SDV]Life Sciences [q-bio] ,Gaussian method ,Hydrogeology ,spatial variation ,Geometry ,Conditional simulation and Monte Carlo simulations ,02 engineering and technology ,geophysical survey ,regolith ,Seepage ,01 natural sciences ,Electrical resistivity tomography ,020701 environmental engineering ,geography.geographical_feature_category ,Geological surveys ,hard rock ,Monte Carlo methods ,Carlo simulations ,6. Clean water ,Random layer thickness ,Aquifers ,Permeability (earth sciences) ,Geophysics ,Ground water flow ,Uncertainty analysis ,Watersheds ,Geology ,electrical resistivity ,Rocks ,Layer thickness ,0207 environmental engineering ,Experimental watersheds ,India ,Aquifer ,Conditional simulations ,Civil Engineering ,Unstructured grid ,Electrical resistivity tomography (ERT) ,computer simulation ,Groundwater resources ,Conditional simulation and Monte ,0105 earth and related environmental sciences ,stochasticity ,geography ,aquifer ,Bedrock ,Geophysical surveys ,Hydrological properties ,Monte Carlo analysis ,Spatial variability ,Non-Gaussian distribution ,Isoparametric finite elements ,numerical model - Abstract
Stochastic modelling is a useful way of simulating complex hard-rock aquifers as hydrological properties (permeability, porosity etc.) can be described using random variables with known statistics. However, very few studies have assessed the influence of topological uncertainty (i.e. the variability of thickness of conductive zones in the aquifer), probably because it is not easy to retrieve accurate statistics of the aquifer geometry, especially in hard rock context. In this paper, we assessed the potential of using geophysical surveys to describe the geometry of a hard rock-aquifer in a stochastic modelling framework. The study site was a small experimental watershed in South India, where the aquifer consisted of a clayey to loamy-sandy zone (regolith) underlain by a conductive fissured rock layer (protolith) and the unweathered gneiss (bedrock) at the bottom. The spatial variability of the thickness of the regolith and fissured layers was estimated by electrical resistivity tomography (ERT) profiles, which were performed along a few cross sections in the watershed. For stochastic analysis using Monte Carlo simulation, the generated random layer thickness was made conditional to the available data from the geophysics. In order to simulate steady state flow in the irregular domain with variable geometry, we used an isoparametric finite element method to discretize the flow equation over an unstructured grid with irregular hexahedral elements. The results indicated that the spatial variability of the layer thickness had a significant effect on reducing the simulated effective steady seepage flux and that using the conditional simulations reduced the uncertainty of the simulated seepage flux. As a conclusion, combining information on the aquifer geometry obtained from geophysical surveys with stochastic modelling is a promising methodology to improve the simulation of groundwater flow in complex hard-rock aquifers. (C) 2013 Elsevier B.V. All rights reserved.
- Published
- 2013
- Full Text
- View/download PDF
28. Ischia landslides (Italy): a multidisciplinary approach aimed to the knowledge of soil properties
- Author
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(a) Vingiani S., (b) De Mascellis R., (b) Mele G., (b) Orefice N., (a) Minieri L., and (a) Terribile F.
- Subjects
Landslide ,andic soils ,hydrological properties ,micro-tomography ,Volcanic soils ,Campania landslides ,soil mineralogy ,hydropedology - Abstract
An integrated approach (chemical, hydrological, mineralogical and micro-tomographic) has been used to study the soils of the landslides occurred in the Ischia island (Italy) on April 2006. The study has been carried out on three soil profiles sampled on representative detachment crowns. The main outcome indicates: (i) presence of volcanic soils, very rich in primary glass, characterised by the presence of poorly ordered kaolinite in all horizons and expandable clay minerals only in the deepest horizons (CBb and Cb), (ii) high values of water content near saturation for all soil horizons, (iii) a relevant vertical discontinuity of soil physical properties. In particular, the deep silty horizon (Cb) retains high amounts of water at low matric potential and shows the lowest value of saturated hydraulic conductivity than the other horizons. This microtomographic analysis of this deep horizon indicates a very complex intra-aggregate pore space, which seems an important factor influencing the specific rheological behaviour of this sliding horizon. In terms of pedogenetic processes, the soils of M. Vezzi northern slope are very different from those described for other catastrophic landslides of the Campania region (Sarno, Quindici, etc.), but they have in common the presence, along the soil profile, of marked physical discontinuities surely contributing to the initiation mechanisms of the landslides.
- Published
- 2010
29. Effects of fire ash on soil water retention
- Author
-
J.G. Wesseling, Coen J. Ritsema, and Cathelijne R. Stoof
- Subjects
Soil texture ,Soil Science ,Soil science ,Leerstoelgroep Land degradatie en ontwikkeling ,Silt ,complex mixtures ,moisture retention ,wildfire ,Field capacity ,Organic matter ,Alterra - Centrum Bodem ,Wageningen Environmental Research ,CB - Bodemfysica en Landgebruik ,physical-properties ,Water content ,organic-matter ,chemistry.chemical_classification ,mediterranean soils ,hydrological properties ,Soil Science Centre ,fly-ash ,PE&RC ,erosion ,forest soil ,Infiltration (hydrology) ,chemistry ,Environmental chemistry ,Fly ash ,Soil water ,Land Degradation and Development ,texture ,Geology ,SS - Soil Physics and Land Use - Abstract
Despite the pronounced effect of fire on soil hydrological systems, information on the direct effect of fire on soil water retention characteristics is limited and contradictory. To increase understanding in this area, the effect of fire on soil water retention was evaluated using laboratory burning and heating experiments. In addition, ash-infiltration and ash-incorporation experiments were performed to evaluate the effect of ash on soil water retention. While heating soil to 200 °C and below did not change soil properties, burning and heating to 300 °C and above increased bulk density, clay and silt content, and decreased organic matter and sand content. Burning and heating above 200 °C decreased the amount of water stored at the nine tensions considered, although the effect on soil water retention did not always increase with increasing temperature. Changes were largest for low tensions, i.e. between saturation and field capacity (10 kPa). Heating to 200 °C decreased the amount of plant available water, but despite reducing the amount of water stored at evaluated tensions, burning and heating to 300 °C and above increased the amount of plant available water. This may be caused by more complete combustion of organic matter at the higher temperatures and the production of ash. Direct incorporation of ash into soils did not alter soil texture but increased water retention from saturation to 310 kPa tension. Ash infiltration experiments interestingly had a similar effect, despite the fact that very little ash washed into the samples. Results from these experiments contribute to understanding post-fire changes in hydrological and erosion processes.
- Published
- 2010
30. Hydrological simulation program-Fortran (HSPF) model as a decision support tool for a developing country-A case study from Turkey
- Author
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Baloch, Mansoor Ahmed, Tanık, Ayşe Gül, and Çevre Mühendisliği Ana Bilim Dalı
- Subjects
Mathematical models ,Hydrological properties ,Environmental Engineering ,Water quality ,Çevre Mühendisliği ,Mathematical modelling ,Hydrology ,Water quality modelling ,Hydrological study ,Watershed characteristics - Abstract
Bu çalışmanın amacı detaylı bir havza modeli uygulayarak iklim ve arazi kullanımı değişiklerinin, seçilen havzanın hidrolojisi ile havzadaki yayılı kaynaklardan gelen kirleticiler üzerindeki etkilerini belirlemektir. Diğer bir amaç ise gelişmekte olan ülkelerdeki araştırmacılara veri erişilebilirliğini, veri toplama maliyetini ve model performansını dikkate alan, veri gereksinimi, model sonuçları, maliyet konularında eşik seviyeleri gözeten, maksimum fayda sağlamak için optimize edilmiş, amaca hizmet eden bir havza modellemesi projesinin tasarımında rehberlik etmektir. Bu çalışmada Köyceğiz havzası için havza hidrolojisi ve yayılı kirlenme karakterizasyonu ile iklim ve arazi kullanımı değişikliklerinin havzanın hidrolojisi ve yayılı kaynaklardan gelen kirletici yükleri üzerindeki etkilerini belirlemek amacıyla Better Assessment Science Integrating point and Non-point Sources (BASINS) ve Hidrolojik Simülasyon Programı-Fortran (HSPF) kullanılmıştır. En İyi Profesyonel Yargı (Best Professional Judgment, BPJ) yöntemi ve literatür taraması sonuçları kullanılarak, veri, maliyet ve Model Performans İndeksi arasındaki ilişkiler belirlenmiştir. Bu ilişkilerin belirlenmesinde kanıtın ağırlığı (Weight of Evidence, WoE) analizi baz alınmıştır. Gelişmekte olan ülkelerde kullanmak amacıyla, minimize edilmiş veri gereksinimi, göreceli olarak düşük maliyet ve model sonuçlarının kabul edilebilirliğini içeren BASINS/HSPF uygulamasını kapsayan bir hipotez geliştirmek için nesnel kanıtlar ileri sürülmüştür. The aim of this study is two folds. The primary aim of the study is to apply a detailed watershed model for the quantification of climate and land use change impacts on the hydrology and NPS pollution in the case study watershed in a developing country. Secondly, it aims to develop a pathway for researchers in developing countries that takes into account the data availability, cost of data collection and model performance to design a watershed modelling project tailor made to the specific modelling objectives based on a threshold level of data requirement, model results and cost, optimized for maximum benefit. In this study Better Assessment Science Integrating point and Non-point Sources (BASINS), and Hydrological Simulation Program-FORTRAN (HSPF), are used for the characterization of watershed hydrology and diffuse pollution and quantification of the effects of land use and climate change on the hydrologic regime and NPS pollutant loads in the Koycegiz watershed, Turkey. Based on the Weight of Evidence (WoE) analysis; Best Professional Judgment (BPJ) in modeling experience and literature review are used to define the relationships between Data, Cost and Model Performance Index and objective evidences are put forth to develop a hypothesis incorporating an application scenario for BASINS/HSPF application in a developing country identifying the minimum data requirement, corresponding relative cost and acceptability of model results, respectively. 184
- Published
- 2009
31. Andic soils and catastrophic mudflows in Italy: hydro-pedological cause-effect evidences
- Author
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(1)Iamarino M., (2)R. De Mascellis, (2)A. Basile, (1)P. Moretti, and (1)F. Terribile
- Subjects
andic properties ,hydrological properties ,mud flow - Abstract
Mudflows are between the major catastrophic types of landslides occurring in Italy especially in terms of victims and damages. An integrated pedological and hydrological analysis has been performed in Calabria, Campania, Toscana and Lombardia regions on the detachment crowns of some of the most important catastrophic mudflows occurred in Italy in the last decades, including the slides of Sarno (1998), Salerno (1910, 1924, 1954), Platì (1951), Versilia (1996) and Albaredo (1987, 2002) sites. A detailed hydro-pedological study performed in the Campania region, using a 2D Richard's based water balance simulation model, addressed the following issues: (i) the importance of hydrological properties of andic soils, namely soils having large quantities of poorly ordered clay minerals; (ii) the interruption of the pedological continuity of the slope and (iii) the relationship with slope aspect. The main results show an increase in soil water storage (more than 30%) in both North facing landscapes and in slope having an interruption in pedo-continuity with respect to some references. Overall the results at national scale revealed an evident association between the investigated catastrophic mudflows and the presence of andic soils, both in the detachment crowns and on the slopes. We believe that these soils because of the unique hydrological properties and high tixotropy induced high vulnerability in landslide triggering and development mechanisms.
- Published
- 2009
32. Measuring soil hydrological properties in different climatic scenario
- Author
-
BITTELLI, MARCO, WORLD METEOROLOGICAL ORGANIZATION (WMO) FOOD AND AGRICULTURE ORGANIZATION (FAO), and Bittelli M.
- Subjects
SOIL ,CLIMATE ,MAPPING ,WATER CONTENT ,HYDROLOGICAL PROPERTIES - Published
- 2005
33. Scaling and carrosion problems in Denizli-Çürüksü right Side plains and hydrogeological aspects
- Author
-
Bariş, Nesrin, Filiz, Şevki, and Jeoloji Mühendisliği Ana Bilim Dalı
- Subjects
Hydrological properties ,Jeoloji Mühendisliği ,Geological Engineering ,Hydrogeology ,Denizli-Çürüksu ,Hydrogeochemistry - Abstract
ÖZET İnceleme alanı, İç Ege Bölgesinde Denizli il merkezine 15 km uzaklıkta yaklaşık 250 km2 alanı kapsar. Araştırmanın amacı, bölgenin hidrolojik, hidrojeolojik ve hidrokimyasal özelliklerini ortaya koymak ve birbirleri ile oran ilişkilerini saptamaktır. İnceleme alanında alttan üste Paleozoyik yaşlı şistler ve mermerler, Alt Pliyosen yaşlı gölsel ve Pliyo-Kuvaterner yaşlı karasal çökeller ile traverten, alüvyon ve yamaç molozu birimleri ayırtlanmıştır. Hazne kayalar üstten alta traverten, Pliyosen kireçtaşlan, Paleozoyik yaşlı mermerler ve olası gnayslardır. Örtü kayalar ise Alt Pliyosen birimin killi ve siltli seviyeleridir. Beslenme, yağış suları, Çivril-Baklan Ovası ve Acıgöl Havzasından gelen yeraltı sulan tarafından sağlanır. Yeraltı sulan sıcaklık ve debileri kararlı bir sistemi gösterirler. Yeraltı sularının sıcaklığı orta kesimlerden güney ve kuzeydeki fay zonlarına doğru bir yükselme gösterir. İzotop analizleri sonuçlan ovanın kuzey ve güneyi arasındaki ilişkiyi ortaya koymuştur ve sadece kuzeyden güney batıya bir alam gözlenebilmiştir. Elde edilen sonuçlar yeraltısuyu rezervuarının kümülatif yağışların etkisinde olduğunu ve pompalamanın çok az bir etkisinin olabileceğini göstermiştir. Çürüksu sağ sahil sulaması için eksik su miktarı 2388 lt/s'dir. Gökpınar Barajından Temmuz ve Ağustos aylarında Çürüksu sağ sahil sulamasına 2400 It's verilerek eksik sulama suyu gereksiniminin karşılanması planlanmıştır 141
- Published
- 1995
34. Investigation of hydrologic and hydraulic design criteria of bridges
- Author
-
Coşkun, Feridun, Yanmaz, A. Melih, and Diğer
- Subjects
Hydrological properties ,Design ,İnşaat Mühendisliği ,Civil Engineering ,Bridges ,Hydraulic systems - Abstract
ÖZ KÖPRÜLERİN HİDROLOJİK VE HİDROLİK TASARIM KRİTERLERİNİN ARAŞTIRILMASI COŞKUN, Feridun Yüksek Lisans Tezi, inşaat Mühendisliği Anabilim Dalı Tez Yöneticisi: Doç.Dr. A.Melih YANMAZ Ağustos, 1994, 199 sayfa Taşkınlar esnasında bir çok köprü hasara ulamakta veya tamamen yıkılmaktadır. Hasarın nedeni yapı tasarımındaki eksiklik değilse, köprü tasarımında hidrdojik ve hidrolik parametrelerin yeterince göz önüne alınmamasından kaynaklanabilir. Köprü ayakları ve mesnetleri etrafındaki yerel oyulmanın mekaniği, bu elemanlar etrafında oluşan zamana bağımlı, üç boyutlu ve katı madde taşıyan türbûlanslı akımın karmaşıklığından dolayı tam olarak anlaşılamamıştır. Bu nedenle, geniş bir tasarım parametresi aralığı için geçerli dan ve tüm dünyada kabul edilen bir tasarım yöntemi henüz getirilememiştir. Köprü tasarımında, deneysel denklemler, benzeşim modelleri, arazi etütleri ve mühendislik kabullerine dayanan hidrolojik ve hidrolik tasarım parametreleri köprü etrafında yapılacak koruyucu önlemlerle birleştirilmelidir.. Bir köprü tasarımında gerekli dan yersel parametrelerin tayini bir örnek çalışmada gözden geçirilmiştir. Vakfıkebir'de mevcut bir köprünün hidrolojik ve hidrolik tasarımı, hidroekonomik analizle elete edilen bir yinelenme dönemine karşı gelen taşkın debisi için tekrarlanmıştı-. Anahtar Kelimeler: Hidrdojik ve Hidrolik Tasarım Köprü, Köprü Ayağı, Mesnet, Yerel Oyulma. Bilim Dalı Sayısal Kodu: 624.02.02 iv ABSTRACT INVESTIGATION OF HYDROLOGIC AND HYDRAULIC DESIGN CRITERIA OF BRIDGES COŞKUN. Feridun M.S. in Civil Engineering Supervisor: Assoc. Prof.Dr. A.Melih YANMAZ August, 1994. 199 pages Many bridges are destroyed or completely failed during floods. If the cause of the damage is not a structural deficiency, it may be due to insufficient hyorologjc and hydraulic evaluations in bridge design. The mechanism of the local scour around bridge piers and abutments has not been completely understood so far due to the complexity of time dependent three dimensional sediment laden turbulent flew around these obstacles. That is why a universal method considering wide range of design parameters has not been developed yet. Hyorologjc and hydraulic aspects of bridge design based on empirical equations, simulation models, field surveys and engineering judgement are to be accompanied with the protective measures in the dose proximity of bridges. In this thesis, local parameters involved in tfıe desigi of a bridge were determined on a case study. Hydrologic and hydraulic design of the piers and abutments of an existing bridge situated in Vakfıkebir have been repeated for a flood having an optimum return period obtained from a hydroeconomic analysis. Keywords: Hydrologic and Hydraulic Design, Bridge, Bridge Pier, Abutment, Local Scour. Science Code : 624.02.02 in 199
- Published
- 1994
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