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Khereddine Boutebba, Ali Bouamrane, Nawel Ganaoui and Mohamed T. Bouziane

Abstract

This article presents the results of a survey using a questionnaire conducted in Algeria, to evaluate the quality of public drinking water service, and at the same time the level of dissatisfaction / satisfaction of the subscribers. A statistical analysis of the data has been conducted on a representative sample of general population to identify weaknesses and strengths related to the current state of water management. The assessment of the quality of service, and the quality of water, as well as the price of water under the influence of the geographical distribution of the population was also studied.

The results of the statistical analyses show a wide variability regarding the level of dissatisfaction/satisfaction of the subscribers. In order to simplify the interpretation, we gathered the results in the form of classes and groups in such way that the cities appear on GIS mapping software, with their inhabitants’ degree of satisfaction.

Open access

M.G.Y.L. Mahagamage, Pavithrani S. Manage and Pathmalal M. Manage

Abstract

In Sri Lanka, among 2588 Salmonella positive cases, the highest incidences were recorded from Jaffna peninsula during 2005 to 2013. Therefore, the present study aimed to identify the microbiological and chemical contamination status of groundwater (40 well water) sources in Jaffna during November 2016. The total coliform, E. coli, Salmonella spp. and Shigella spp. along with some physico-chemical parameters of groundwater were studied. The results revealed that entire peninsula was contaminated with total coliform and E. coli bacteria and the parameters recorded were not within the WHO and SLS (Sri Lanka Standards) drinking water quality standards. 38% of sampling locations were positive for Salmonella spp. and among them six sampling locations were being used for drinking purposes. The results of the study correlates with the statistics of typhoid cases recorded in Jaffna. Results of the study also revealed that around 80% of wells were not within the values specified in guidelines of the SLS for drinking water quality on electrical conductivity. Further, 15% of wells recorded greater than 10 mgꞏdm–3 nitrate, which is still below the SLS drinking water standards (45 mgꞏdm–3). According to the water quality data, PCA analysis showed that Jaffna town, Nallur, Tellippalai and Kopay DS divisions has similar characteristics for water quality.

Open access

Noureddine Merniz, Ali Tahar and Amine M. Benmehaia

Abstract

In the present study, time series for annual, monthly rainfall and number of rainy days per year were analysed to quantify spatial variability and temporal trends for 22 rainfall stations distributed in northeastern Algeria for the period 1978–2010. The Mann–Kendall test and the Sen’s slope estimator were applied to assess the significance and magnitude of the trend. The results showed that precipitation decreases spatially from North to South and from East to West. The application of the Mann–Kendall test (for 0.05% threshold) to the time series data showed that for annual precipitation, no station showed statistically significant trends, unlike the number of rainy days, where there was a significant negative trend in four stations (Jijel, Constantine, Oum El Bouaghi and Tébessa). For the monthly time series, significant positive trends were observed during the months of September in the coastal stations and July for the plateaus and southern Saharan Atlas stations, while significant negative trends were recorded during the months of February and March for the stations of the extreme East in the study area. These results revealed that for the period analysed, there was no significant climate change in northeastern Algeria but there is a seasonal delay having important agroecological implications.

Open access

Rustinsyah Rustinsyah and Ratna A. Prasetyo

Abstract

The fostering and empowerment of water user associations (WUAs) has been regulated by the Minister of Agriculture since 2012. However, the implementation of this guideline varies. Some water user associations have achieved improvement, while some others have not. This study discusses how a WUA in the villages that use Bengawan Solo River water has successfully managed the irrigation. One of the factors leading to the success of this WUA is the stakeholder engagement in the agricultural irrigation management and farm business. This study was conducted from June 2016 to June 2017 by employing a qualitative approach. It aimed to identify and understand the stakeholder engagement in agricultural irrigation management by: 1) conducting an analysis on stakeholder power and interest indices, 2) mapping the positions, responsibilities, and obligations of stakeholders, and 3) identifying the stakeholder engagement in agricultural irrigation management. The research results are as follows: a) the analysis using Likert scale showed that the power index reached a value of 0.76, while the interest index reached a value of 0.78; b) the mapping of internal stakeholders, especially the responsibilities and obligations, has been regulated under the Articles of Incorporation of WUAs and obligations of external stakeholders, especially the government in making government regulations, irrigation infrastructure support, and flood prevention; c) cooperation of the stakeholders has an important role in the agricultural irrigation management and in solving the problems faced by WUAs.

Open access

Alex Barakagira and Anton H. de Wit

Abstract

Wetlands in Uganda are believed to be socio-economically important for providing water for drinking, irrigation, fisheries, recreation, transport and agriculture among others. Bearing in mind the host of benefits wetlands provide to local communities, if they are harnessed without the mind, they could end up being over utilized and ultimately degraded and not continue to provide a stream of functions, attributes and services. This could be one of the primary reasons why special Departments and Institutions like the National Environment Management Authority and Wetlands Management Department were created to manage the country’s natural resources including wetlands. The study was initiated to explore how wetland management agencies influence members of the local community on matters concerning the conservation of wetlands in Uganda. A cross-sectional research design was used to collect qualitative and quantitative data. A questionnaire survey was conducted amongst four hundred households to collect information concerning the role of wetland management agencies among members of the local community for the conservation of wetlands in Uganda. More information was obtained from senior officials from the National Environment Management Authority, Wetland Management Department, and District Natural Resources Officers from the study area using a non-structured questionnaire. Key informant interviews and direct observations were also used to collect data. The study revealed that gathering materials for building and for making crafts, agricultural activities, unsustainable mining of clay and sand for building contributed to wetland degradation. Some circumstances like high population growth, unclear wetland ownership, unawareness of the indirect functions of wetlands also contributed to wetland degradation. It was found that the wetland management agencies have been ineffective towards the conservation of wetlands mainly due to inadequate funding, political interference, and lack of specific judges for wetland related court cases among others. For wetland management agencies to effectively perform their duties leading to the protection and conservation of wetlands in Uganda, the study recommends that members of the local community should be allowed to practice wetland edge farming, fish farming in ponds constructed in wetlands, and to leave some parts of these vital wetlands that have been reclaimed to regenerate, in addition to addressing the main reported hindrances that are stifling the smooth running of the activities of the agencies.

Open access

Chokri Bedoui

Abstract

This study was conducted with a view to quantifying soil erosion in arid lands of Tunisia. To do this, we have opted to use the RUSLE model based on geographic information systems. By collecting data on rainfall, soils, vegetation, slopes and conservation practices separately as a layer and determining the pixel values for each of these factors, a quantified assessment of erosion in the basin is obtained. The data superposition and computing, following the model equations and protocol, allowed us to know the spatialized water erosion values at the pixel level. For the whole catchment, the study showed values oscillating between 0 and 163 Mgꞏha−1ꞏyear−1 with an average annual rate of 3 Mgꞏha−1ꞏyear−1. With such a low R (rainfall erosivity) factor (between 21.43 and 21.88 MJꞏmmꞏha–1ꞏh–1ꞏyear–1) itself related to low monthly and annual rainfall amounts, the region experiences locally very high annual erosion rates. Soil protection through conservation practices has saved the basin from even higher erosion. While plains cultivated and equipped with contour benches often suffer from low rates of erosion (less than 2 Mg·ha–1·year–1), unused slopes are neglected without protection, resulting in significantly high rates of erosion.

Open access

Małgorzata Gałczyńska, Natalia Mańkowska, Justyna Milke and Marta Buśko

Abstract

The paper presents the assessment of possibilities and limitations of the use of Lemna minor, Hydrocharis morsus-ranae and Ceratophyllum demersum in removing metals from contaminated waters. Synthetically discussed the role of these species in phytotechnology and their importance in the assessment of surface water status. The variability of concentration of selected metals in waters and the content of metals in the organs of the analysed plants are presented. Their advantages and disadvantages in removing metals from waters due to biological features have been characterized. Minimum and maximum efficiency of metal removal depending on the scale of water pollution was determined. It was found that analysed plants can be used for phytoremediation of metals from water, but the limitation of effectiveness of treatments is the toxicity of these metals to plants and the time of exposure. The highest removal efficiency can be obtained thanks to the use of sequences of single-species filtration systems.

Open access

Marian Poniewiera, Iwona Jelonek and Wioleta Błaszczak-Bąk

Abstract

The purpose of the work described in the article was to find the optimal location of the pumping station for the mining area Krzyżowice III Hard Coal Mine “Pniówek”. Mining exploitation causes lowering of the area and changes in water relations. Hence, it is necessary to perform a gravitational, and if it is impossible, forced outflow of water. Localization of the pumping station should assure removal of excess water and prevent flooding. Not only was the present relief taken into account, but also the entire period of the mine’s existence. On the basis of the results of airborne laser scanning a digital terrain model (DTM) was generated. Then a catchment division was made for the entire analyzed area. The article presents the workflow of performing the simulation as the area will be changed due to forecasted mining operations. A practical way to solve the problem of simplifying large amounts of data was also shown. The obtained source materials were developed with the use of the Geolisp software. The system operates in a CAD graphic environment and allows for automation of the most frequently performed works in the field of mining map preparation. The Geolisp cooperates with EDN-OPN program. Thanks to this fact it is possible to combine the obtained results of calculations of predicted deformations of the mining area and the rock mass with the digital map.

Open access

Bogumił M. Nowak and Mariusz Ptak

Abstract

The article presents the analysis of water level fluctuations in Lake Powidzkie in the years 1961–2015. The study shows a considerable decrease in mean water levels in the aforementioned multiannual period, averaging 9 cmꞏdecade−1. Such a situation is caused by natural as well as anthropogenic factors, co-determining water relations in the study area. The natural factors include the amount and distribution of precipitation, increase in air temperature and evaporation size, unfavourable relations between the lake and catchment or hydrogeological conditions. Anthropogenic factors particularly include long-term transformations of the natural environment in the region, currently associated with meliorations accompanying the nearby opencast brown coal mines and exploitation of groundwaters for municipal purposes. Water shortages occurring during dry periods were shown not to be compensated in the study area in humid years. This is particularly related to the regional lowering of the aquifer remaining in close relations with Lake Powidzkie. Counteracting the unfavourable hydrological situation is done through hydrotechnical infrastructure which partially limits water outflow from the lake through damming.

Open access

Krzysztof Micun and Sławomir Roj-Rojewski

Abstract

The aim of the study was to determine the morphological characteristics of selected spring-heads in the Knyszyńska Primeval Forest and to identify lithological conditions in areas where groundwater flows to the surface. During the study, detailed bed level measurements of the spring-head areas were conducted. Lidar laser data obtained from the Central Department of Geodetic and Cartographic Documentation in Warsaw were also used for the analysis of morphometry. Based on the data, the detailed contour maps were created in the Surfer 12 programme and the basic parameters of the morphometry of the studied springs were determined. To detect lithological conditions, granulometric analyses were conducted and the filtration coefficient of aquifers in the individual spring-heads was calculated using Hazen and USBSC empirical models. Due to the morphological situation, the examined objects were classified as sub-slope and riverbank spring-heads. In terms of shape, spring-head alcoves are classified as basin-shaped, bowl-shaped and spindle-shaped alcoves. Different morphological processes prevail in each of these types. Basin-shaped alcoves are formed mainly by lateral erosion, bowlshaped alcoves by seepage erosion, landsliding and accumulation in the bottom, spindle-shaped alcoves by seepage erosion, headward erosion, breaking and collapsing. In the investigated outflows of groundwater aquifers are sands and glacifluvial sands with gravel of varying grain size. The lithological variation of aquifers in the spring-heads, directly affects the rate of groundwater filtration in different parts of the alcoves, which in turn leads to different morphogenetic processes and results in changes in the morphology of the spring-head alcoves.