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Number of results: 22
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Abstract

Arid areas are particularly susceptible to soil erosion due to long dry periods and sudden heavy downpours. This study investigates the aggregate size distribution and aggregate stability of twelve tilled fallow areas of Hyderabad district, Sindh, Pakistan. This study determined aggregate size distribution by dry sieving to evaluate the seedbed condition and aggregate stability using wet sieving to assess the susceptibility of tilled fallow areas to soil erosion. The aggregate size distribution of the soils of the selected areas was highly variable. Gulistan-e-Sarmast had the largest number of clods (51.0%) followed by Kohsar (49.0%), Latifabad # 10 (41.10%) and Daman-e-Kohsar (39.0%). Fazal Sun City, the left side of the Indus River, the Village Nooral Detha and the left side of the Abdullah Sports city had a greater number of large (>8.0 mm) and small aggregates (<0.5 mm). The optimum aggregate size distribution was found in the left side of the channel, which had the largest number of aggregates (50.50%) in the 0.5–8.0 mm sieve size range. Maximum aggregate stability (AS) was found in Gulistan-e-Sarmast (46%), Kohsar (42%) and Latifabad # 10 (34%), while all other soils had minimum aggregate stability (<14%). The minimum aggregate stabilities demonstrate that the tilled fallow areas of Hyderabad district are highly susceptible to erosion. Therefore, the present study suggests investigating potential ways to enhance the aggregate stabilities of soils.

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Authors and Affiliations

Ahmed Tagar
Jan Adamowski
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Abstract

CropSyst model can be used as irrigation water management tool to increase wheat productivity with poor quality water. The objective of this study was to calibrate CropSyst model for wheat irrigated with fresh and agricultural drainage water. To do so, three field experiments were conducted during three successive seasons in Nubaria Agricultural Research Station, Egypt representing the newly reclaimed calcareous soils. In the first season the treatments were 100% crop evapotranspiration (ETc) of fresh water (FW) and 100% ETc of agricultural drainage water (DW), while in the second and the third seasons, the treatments were 100% ETc of FW, 100% ETc of DW, 120% ETc of DW and 130% ETc of DW. From these results one can concluded that deducting 5% of the applied water to all treatments reduced yield by 3, 5 and 7% in the first, second and third growing season, respectively as a result of heat stress existed in the 2nd and 3rd seasons during reproductive phase. Furthermore, deducting 5% of the applied water from all treatments in the vegetative phase only resulted in lower yield losses. Thus, using CropSyst model could guide us to when we could reduce the applied irrigation water to wheat to avoid high yield losses.

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Authors and Affiliations

Samiha A. Ouda
Tahany Noreldin
Oussama H. Mounzer
Magdi T. Abdelhamid
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Abstract

The construction of dams in rivers can offer many advantages, however the consequences resulting from their failure could result in major damage, including loss of life and property destruction. To mitigate the threats of dam break it is essential to appreciate the characteristics of the potential flood in realistic manner. In this study an approach based on the integration of hydraulic modelling and GIS has been used to assess the risks resulting from a potential failure of Zardezas dam, a concrete dam located in Skikda, in the North East of Algeria. HEC-GeoRAS within GIS was used to extract geometric information from a digital elevation model and then imported into HEC-RAS. Flow simulation of the dam break was performed using HEC-RAS and results were mapped using the GIS. Finally, a flood hazard map based on water depth and flow velocity maps was created in GIS environment. According to this map the potential failure of Zardezas dam will place a large number in people in danger. The present study has shown that Application of Geographical Information System (GIS) techniques in integration with hydraulic modelling can significantly reduce the time and the resources required to forecast potential dam break flood hazard which can play a crucial role in improving both flood disaster management and land use planning downstream of dams.

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Authors and Affiliations

Oussama Derdous
Lakhdar Djemilil
Hamza Bouchehed
Salah Eddine Tachi
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Abstract

Groundwater contamination due to leakage of gasoline is one of the several causes which affect the groundwater environment by polluting it. In the past few years, In-situ bioremediation has attracted researchers because of its ability to remediate the contaminant at its site with low cost of remediation. This paper proposed the use of a new hybrid algorithm to optimize a multi-objective function which includes the cost of remediation as the first objective and residual contaminant at the end of the remediation period as the second objective. The hybrid algorithm was formed by combining the methods of Differential Evolution, Genetic Algorithms and Simulated Annealing. Support Vector Machines (SVM) was used as a virtual simulator for biodegradation of contaminants in the groundwater flow. The results obtained from the hybrid algorithm were compared with Differential Evolution (DE), Non Dominated Sorting Genetic Algorithm (NSGA II) and Simulated Annealing (SA). It was found that the proposed hybrid algorithm was capable of providing the best solution. Fuzzy logic was used to find the best compromising solution and finally a pumping rate strategy for groundwater remediation was presented for the best compromising solution. The results show that the cost incurred for the best compromising solution is intermediate between the highest and lowest cost incurred for other non-dominated solutions.

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Authors and Affiliations

Deepak Kumar
Sudheer Ch
Shashi Mathur
Jan Adamowski
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Abstract

One more time we would like to pay attention of especially of the hydraulic engineer audience to bankfull stage and discharge. Along the paper we show commonly accepted definitions of it and ways of calculations. It is difficult to determine the size of the bankfull flow level, that is why the authors are presenting many selected methods. Some of the methods allow the determination of biotic bankfull flow through the occurrence of zones of vegetation characteristic and based on the observation of the occurrence of ground beetles (e.g. the Woodyer and the Radecki-Pawlik and Skalski methods). Some of the methods – most popular- are using morphometric parameters (e.g. the Williams, the Hey and Thorne, the Gauckler-Manning and finally the Lambor methods).

We believe that the value of bankfull discharge would be accepted as a supporting tool for designers, hydraulics engineers and managers, especially those who care about river channel environment and cooperate with fluvial geomorphologists- and biologists as well as environmental agencies.

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Authors and Affiliations

Artur Radecki-Pawlik
ORCID: ORCID
Tomasz Skalski
Karol Plesiński
Wiktoria Czech
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Abstract

The variability of the mean annual air temperature and precipitation totals in three periods: 1848–2010, 1951–2010 and 1981–2010 was investigated in the large Warta River basin, being the area with lowest rainfall in Poland. For the purposes of research, nine meteorological stations with the longest measurement series were selected. Air temperature increase in this river basin was similar than in neighbouring countries. In the last 30 years this trend kept increasing. The precipitation in the whole studied period was slightly increasing in the northern part of the Warta River basin, but decreasing in the southern part. The mean annual precipitation totals in the catchment area did not change visible. In the period 1981–2010, the precipitation totals show a small increase in the winter and spring and a decrease in summer. A negative influence of this climate change was not visible in the Warta River discharge. The main objectives of this study were the collection long-term records of air temperature and precipitation in the Warta River basin, and the statistical analysis of climate variability.

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Authors and Affiliations

Piotr Ilnicki
Ryszard Farat
Krzysztof Górecki
ORCID: ORCID
Piotr Lewandowski
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Abstract

Długo sądzono, że RNA to cząsteczka wyspecjalizowana w przenoszeniu informacji z DNA na białko. Stosunkowo niedawno naukowcy odkryli, jak bardzo złożony jest świat RNA
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Authors and Affiliations

Witold Filipowicz
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Abstract

Współczesna technologia umożliwia analizowanie próbek liczących sobie nawet do miliona lat. Czy dzięki polskim badaniom z wykorzystaniem kopalnego DNA tur powróci do naszych lasów?
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Authors and Affiliations

Ryszard Słomski
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Abstract

Cechą Internetu jest przeładowanie informacyjne. Wraz z nadmiarem dostępnych treści pojawia się niedobór uwagi użytkowników. Niezbędne stają się społeczne i technologiczne rozwiązania zapewniające selekcję treści istotnych i adekwatnych dla użytkownika.
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Authors and Affiliations

Dominik Batorski
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Abstract

Podróżując po Polsce i po świecie, podziwiamy krajobrazy, które wydają się stałymi, od zawsze istniejącymi, niezmiennymi elementami naszej Ziemi. Możemy mieć takie wrażenie, ponieważ nasza ludzka skala czasu jest niewspółmiernie mała w stosunku do geologicznej - operującej milionami, a nie dziesiątkami czy setkami lat.
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Authors and Affiliations

Magdalena Sidorczuk
Monika Krzeczyńska
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Abstract

Z perspektywy stuleci czy nawet dziesięcioleci ocena, kto był uczonym wybitnym, a kto miernym, wydaje się prosta. Problem oceny współcześnie działających pracowników nauki jest jednak znacznie bardziej złożony.
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Authors and Affiliations

Karol Życzkowski
Agnieszka Pollo
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Abstract

Polskie magazyny zwierzeniowe odważniej niż inne popularne pisma kobiece poruszają problemy drażliwe. Formuła opowieści zwierzeniowej pozwala bowiem na przekroczenie obowiązujących w dyskursie dominującym zakazów wypowiadania.
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Authors and Affiliations

Katarzyna Stańczak-Wiślicz
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Abstract

Prof. Markowski przedstawia możliwości oceny zachowań wyborców w wyborach parlamentarnych na podstawie prowadzonych od wielu lat badań Polskiego Generalnego Studium Wyborczego.
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Authors and Affiliations

Radosław Markowski
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Abstract

W czasach Kopernika kanoników chowano pod ołtarzami, przy których służyli do mszy. Naukowcy zaczęli więc poszukiwanie grobu wielkiego astronoma od ołtarza św. Andrzeja we fromborskiej katedrze.
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Authors and Affiliations

Wiesław Bogdanowicz
Patrycja Dołowy
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Abstract

Terapie obecnie stosowane w niewydolności serca nie są skierowane na wewnątrzkomórkowe szlaki regulacyjne metabolizmu kardiomiocytów, tymczasem badania pokazują, że byłaby to skuteczna metoda leczenia.
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Authors and Affiliations

Paweł Dobrzyń
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Abstract

Open Access w nauce i Open Science - idee otwartego dostępu i otwartej nauki - to koncepcje publikowania materiałów naukowych, tak by były jak najbardziej dostępne dla odbiorców.
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Authors and Affiliations

Patrycja Dołowy
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Abstract

Rozmowa z Prof. Ryszardem Tadeusiewiczem
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Authors and Affiliations

Ryszard Tadeusiewicz
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Abstract

Dzięki prowadzonemu w Instytucie Psychologii UAM w Poznaniu projektowi badawczemu adaptowane są narzędzia do diagnozy rozwoju małych dzieci.
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Authors and Affiliations

Anna Izabela Brzezińska
Elżbieta Hornowska

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