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Open access

Landoni Adriano, Ansaldi Silvia, Bragatto Angelo and Pittiglio Paolo

The Quantitative Area Risk Analysis to Support Decision on Lpg Depots and Land Use Planning

In Italy, for assessing LPG depots, a simplified method has been used for twelve years. The method is based on the classification of the plant according the MOND index. Standardized accidental scenarios are applied to have damage areas. Land vulnerability and compatibility are evaluated according a method inspired by the IAEA method for land use compatibility. In this paper it has been demonstrated credible, as their results are confirmed by using a higher level method, such as the well known method defined in the TNO purple book.

Open access

Fabrizio Ungaro, Costanza Calzolari, Alberto Pistocchi and Francesco Malucelli

Abstract

Soil sealing is the permanent covering of the land surface by buildings, infrastructures or any impermeable artificial material. Beside the loss of fertile soils with a direct impact on food security, soil sealing modifies the hydrological cycle. This can cause an increased flooding risk, due to urban development in potential risk areas and to the increased volumes of runoff. This work estimates the increase of runoff due to sealing following urbanization and land take in the plain of Emilia Romagna (Italy), using the Green and Ampt infiltration model for two rainfall return periods (20 and 200 years) in two different years, 1976 and 2008. To this goal a hydropedological approach was adopted in order to characterize soil hydraulic properties via locally calibrated pedotransfer functions (PTF). PTF inputs were estimated via sequential Gaussian simulations coupled with a simple kriging with varying local means, taking into account soil type and dominant land use. Results show that in the study area an average increment of 8.4% in sealed areas due to urbanization and sprawl induces an average increment in surface runoff equal to 3.5 and 2.7% respectively for 20 and 200-years return periods, with a maximum > 20% for highly sealed coast areas.

Open access

Klára Macsinka

Abstract

The article introduces main results of a research about defining parking needs to land use functions on the principles of sustainable mobility. Objective of the research was to find a method of determining differentiated, realistic (and environmentally friendly) parking standards applicable in the practice of urban planning and traffic design. Process of the work is briefly presented. Existing Hungarian practice of determining parking demands for different land use functions and zones is dealt with, pointing out problems, inconsequent issues and necessity of an urgent review. Factors to be taken into consideration (land use type, location within the city structure, accessibility and service level of public transportation system, simultaneity of usage land use zones, etc.) are listed. A model for calculation of realistic parking needs is shown. Needs and possible directions of further research are explained.

Open access

Tomasz Orczykowski and Andrzej Tiukało

Abstract

Land use is considered as a non-structural, ecologically beneficial flood protection measure. Forest as one of the land use types has many useful applications which can be observed in detail on www.nwrm.eu website project. It is scientifically proved that afforestation influences flood events with high probability of occurrence. However, it is still to be argued how to measure land use impact on the hydrological response of watershed and how it should be measured in an efficient and quantifiable way. Having the tool for such an impact measurement, we can build efficient land management strategies. It is difficult to observe the impact of land use on flood events in the field.Therefore, one of the possible solutions is to observe this impact indirectly by means of hydrological rainfall-runoff models as a proxy for the reality. Such experiments were conducted in the past. Our study aims to work on the viability assessment, methodology and tools that allow to observe this impact with use of selected hydrological models and readily available data in Poland. Our first reaserch site is located within headwaters of the Kamienna river watershed. This watershed has been affected by ecological disaster, which resulted in loss of 65% of forest coverage. Our proposed methodology is to observe this transformation and its effect on the watershed response to heavy precipitation and therefore change in the flood risk.

Open access

Mario Pirastru, Vincenzo Bagarello, Massimo Iovino, Roberto Marrosu, Mirko Castellini, Filippo Giadrossich and Marcello Niedda

Abstract

The lateral saturated hydraulic conductivity, Ks,l, is the soil property that mostly governs subsurface flow in hillslopes. Determinations of Ks,l at the hillslope scale are expected to yield valuable information for interpreting and modeling hydrological processes since soil heterogeneities are functionally averaged in this case. However, these data are rare since the experiments are quite difficult and costly. In this investigation, that was carried out in Sardinia (Italy), large-scale determinations of Ks,l were done in two adjacent hillslopes covered by a Mediterranean maquis and grass, respectively, with the following objectives: i) to evaluate the effect of land use change on Ks,l, and ii) to compare estimates of Ks,l obtained under natural and artificial rainfall conditions. Higher Ks,l values were obtained under the maquis than in the grassed soil since the soil macropore network was better connected in the maquis soil. The lateral conductivity increased sharply close to the soil surface. The sharp increase of Ks,l started at a larger depth for the maquis soil than the grassed one. The Ks,l values estimated during artificial rainfall experiments agreed with those obtained during the natural rainfall periods. For the grassed site, it was possible to detect a stabilization of Ks,l in the upper soil layer, suggesting that flow transport capacity of the soil pore system did not increase indefinitely. This study highlighted the importance of the experimental determination of Ks,l at the hillslope scale for subsurface modeling, and also as a benchmark for developing appropriate sampling methodologies based on near-point estimation of Ks,l.

Open access

Jana Kaiglová and Jakub Langhammer

Abstract

This paper presents the results of testing the applicability of the MIKE Basin model for simulating the efficiency of scenarios for reducing water pollution. The model has been tested on the Olšava River Basin (520 km2) which is a typical rural region with a heterogeneous mix of pollution sources with variable topography and land use. The study proved that the model can be calibrated successfully using even the limited amount of data typically available in rural basins. The scenarios of pollution reduction were based on implementation and intensification of municipal wastewater treatment and conversion of arable land on fields under the risk of soil erosion to permanent grassland. The application of simulation results of these scenarios with proposed measures proved decreasing concentrations in downstream monitoring stations. Due to the practical applicability of proposed measures, these could lead to fulfilment of the water pollution limits required by the Czech and EU legislation. However, there are factors of uncertainty that are discussed that may delay or limit the effect of adopted measures in small rural basins.

Open access

Peter Rončák, Kamila Hlavčová and Tamara Látková

Abstract

Distributed rainfall-runoff model simulations are often used to evaluate the impact of changes on the generation of runoff. These models have the advantage of reflecting the effects of land use on spatially distributed model parameters. The article deals with changes in forest associations as a result of global climate changes. In this article the WetSpa model was used for estimating the impact of forest changes on the runoff regime in the Hron and Topla river basins, with an emphasis on the parameterization of the land cover properties in the runoff simulations. The parameters of the model were estimated using climate data and three digital map layers: a land-use map, soil map and digital elevation model. This work contains two land use change scenarios of forest associations and also two scenarios of global climate change. Both types of scenarios of changes were prepared, and the runoff under the new conditions was simulated.

Open access

Martin Šanda, Pavlína Sedlmaierová, Tomáš Vitvar, Christina Seidler, Matthias Kändler, Jakub Jankovec, Alena Kulasová and František Paška

Abstract

The objective of the study was to evaluate the spatial distribution of peakflow pre-event water contributions and streamwater residence times with emphasis on land use patterns in 38 subcatchments within the 687 km2 large mesoscale transboundary catchment Lužická Nisa. Mean residence times between 8 and 27 months and portions of pre-event water between 10 and 97% on a storm event peakflow were determined, using 18O data in precipitation and streamwater from a weekly monitoring of nearly two years. Only a small tracer variation buffering effect of the lowland tributaries on the main stem was observed, indicating the dominant impact on the mountainous headwaters on the runoff generation. Longest mean streamwater residence times of 27 months were identified in the nearly natural headwaters of the Jizera Mountains, revealing no ambiguous correlation between the catchment area and altitude and the mean residence time of streamwater. Land use control on the pre-event water portions were determined for three land use categories with percentage of urban areas from 0 to 10%, 10 to 20% and more than 20%. The fraction of pre-event water in the first category decreases from 97% to 65% with the increasing percentage of forest from 76% to 100%, revealing that forests may provide only a limited infiltration of precipitation due to leaf interception and soil water use for transpiration. Fractions of pre-event water of 39–87% in the second (agricultural catchments) and of 10–35% in the third (urbanized catchments) category increase with percentage of non-urban areas.

Open access

P. Valent, P. Rončák, M. Maliariková and Š. Behan

Abstract

The way land is used has a significant impact on many hydrological processes that determine the generation of flood runoff or soil erosion. Advancements in remote sensing which took place in the second half of the 20th century have led to the rise of a new research area focused on analyses of land use changes and their impact on hydrological processes. This study deals with an analysis of the changes in land use over a period of almost three centuries in the Myjava River catchment, which has an outlet at Šaštín-Stráže. In order to obtain information about the way the land was used in the past, three historical mappings representing various periods were used: the first (1st) military mapping (1764-1787), second (2nd) military mapping (1807-1869), and a military topographic mapping (1953-1957). The historical mappings have been manually vectorised in an ArcGIS environment to identify various land use categories. The historical evolution of land use was further compared with a concurrent land use mapping, which was undertaken in 2010 and exploited remote sensing techniques. The study also quantifies the impact of these changes on the long-term catchment runoff as well as their impact on flows induced by extreme precipitation events. This analysis was performed using the WetSpa distributed hydrological model, which enables the simulation of catchment runoff in a daily time step. The analysis showed that the selected catchment has undergone significant changes in land use, mainly characterized by massive deforestation at the end of the 18th century and land consolidation in the middle of the 20th century induced by communist collectivisation. The hydrological simulations demonstrated that the highest and lowest mean annual runoffs were simulated in the first (1st military mapping) and the last (concurrent land use monitoring) time intervals respectively with the smallest and largest percentages of forested areas.

Open access

Bahman Amiri, K. Sudheer and Nicola Fohrer

Linkage Between In-Stream Total Phosphorus and Land Cover in Chugoku District, Japan: An Ann Approach

Development of any area often leads to more intensive land use and increase in the generation of pollutants. Modeling these changes is critical to evaluate emerging changes in land use and their effect on stream water quality. The objective of this study was to assess the impact of spatial patterns in land use and population density on the water quality of streams, in case of data scarcity, in the Chugoku district of Japan. The study employed artificial neural network (ANN) technique to assess the relationship between the total phosphorous (TP) in river water and the land use in 21 river basins in the district, and the model was able to reasonably estimate the TP in the stream water. Uncertainty analysis of ANN estimates was performed using the Monte Carlo framework, and the results indicated that the ANN model predictions are statistically similar to the characteristics of the measured TP values. It was observed that any reduction in forested area or increase in agricultural land in the watersheds may cause the increase of TP concentration in the stream. Therefore, appropriate watershed management practices should be followed before making any land use change in the Chugoku district.