Edyta Hewelke

The application of pedotransfer functions in the estimation of water retention in alluvial soils in Żuławy Wiślane, northern Poland

Abstract The aim of the studies was the assessment of the usefulness of selected pedotransfer function for calculating the water retention of alluvial soils in Żuławy Wiślane. Żuławy Wiślane are an important area, both as far as agricultural production and environmental values are concerned. The analysis accounted for three models, i.e.: van Genuchten-Wösten, Varellyay and Mieronienko, Hewelke et al. Based on 122 dataset of alluvial soils from the Żuławy area, the statistical relationships between the measured values of total available water and values calculated for individual models were analysed. The studies carried out indicate that the analysed pedotransfer functions are characterized by different compatibilities with results obtained by means of direct measurement. The lowest average errors of fit were obtained for the Hewelke et al. and van Genuchten models.

Assessment of the possibility of applying selected pedotransfer functions for indicating the retention of forest soils in Poland

Soil retention capacity, that is the ability to retain and store water, is a functional relationship between the matrix potential and volumetric water content (pF curve). In agricultural ecosystems, it determines the choice of crops, crop yields, and the necessary agricultural infrastructure and farming technology. In forests, it infl uences the formation of a given forest habitat type, fl oristic species composition, and type and quality of the stand of trees. It is a soil property which affects the air-to-water ratios and susceptibility of soil to draught (Boczoń, Kowalska, Dudzińska & Wróbel, 2016; Liberacki, Kozaczyk, Stachowski, & Stasik, 2016). The retention of forest soils along with so-called landscape retention infl uence the water balance of a catchment and the course of fl ooding events to a large degree. A review of literature indicates that the retention capabilities of forest soils are much less known than the retention of land used for agriculture. Taking into consideration the key role of forests in absorbing carbon dioxide and compensating for the greenhouse effect, there is good reason to take up studies building on knowledge of the topic (Paschalis-Jakubowicz, 2010). An important argument is also the fact that Scientifi c Review – Engineering and Environmental Sciences (2017), 26 (3), 336–345 Sci. Rev. Eng. Env. Sci. (2017), 26 (3) Przegląd Naukowy – Inżynieria i Kształtowanie Środowiska (2017), 26 (3), 336–345 Prz. Nauk. Inż. Kszt. Środ. (2017), 26 (3) http://iks.pn.sggw.pl DOI 10.22630/PNIKS.2017.26.3.33

INFLUENCE OF SELECTED FACTORS ON ERODIBILITY IN CATCHMENT SCALE ON THE BASIS OF FIELD INVESTIGATION

Drying of soil surface can affect the soil water repellency and reduce the infiltration, it may have impact on runoff and erosion. The aim of the research was to determine the effect of soil surface drying on its repellency and erosion, and the dependence of these values from the land use on the changing weather conditions background during the year. The research was conducted on Zagożdżonka river catchment, six times during the period of July 2014-September 2015, at five measuring points characterized by different land use. The irrigation of soil was carried out using rainfall simulator made by Eijkelkamp company. The intensity of the rain during the first 3 minutes of precipitation was 6 mm / min, the kinetic energy of rain was 72 J·m-2. The surface runoff was collected into containers placed in the bottom of the rainfall simulator. Water Drop Penetration Time test was used to determine soil surface wettability. WET-2 probe was used to measure the moisture and soil temperature. Sediment concentration in the effluent was determined by weight method on filters. Variability of soil wettability was observed in different dates of measurements. Increasing repellency was recorded during the dry periods. The highest class of repellency was found in the forest and wild meadow areas. There was no direct correlation between the soil moisture, soil temperature and runoff. Both, sediment concentrations and sediment grain size, varied in the collected samples, depending on measurement time. The highest sediment concentrations were found in runoff from agricultural land use.

Dynamic simulation of sustainable farm development scenarios using cognitive modeling

Abstract Dynamic simulation of sustainable farm development scenarios using cognitive modeling. The paper presents a dynamic simulation system of sustainable development scenarios on farms using cognitive modeling. The system incorporates relevant variables which affect the sustainable development of farms. Its user provides answers to strategic issues connected with the level of farm sustainability over a long-term perspective of dynamic development. The work contains a description of the model structure as well as the results of simulations carried out on 16 farms in northern Ukraine. The results show that the process of sustainability is based mainly on the potential for innovation in agricultural production and biodiversity. The user is able to simulate various scenarios for the sustainable development of a farm and visualize the influence of factors on the economic and social situation, as well as on environmental aspects. Upon carrying out a series of simulations, it was determined that the development of farms characterized by sustainable development is based on additional profit, which serves as the main motivation for transforming a conventional farm into a sustainable one. Nevertheless, additional profit is not the only driving force in the system of sustainable development. The standard of living, market condition, and legal regulations as well as government support also play a significant motivational role.

INFLUENCE OF CYCLIC FREEZING AND THAWING ON THE HYDRAULIC CONDUCTIVITY OF SELECTED AGGREGATES USED IN THE CONSTRUCTION OF GREEN ROOFS

The construction of a green roof requires drainage which ought to be characterized by adequate hydraulic conductivity and be resistant to changing meteorological conditions during the winter period. A properly functioning drainage system guarantees the reliability of the entire green roof system. The article presents studies on the freeze-thaw durability and hydraulic conductivity of selected aggregates applied for constructing green roof drainage systems. The aggregates were subjected to a cyclic freezing and thawing process in 30 and 70 cycles. The obtained results indicate that the conductivity of aggregates studied using the constant head method decreases along with an increase in the number of freeze-thaw cycles they were subjected to. This means that the indicator of freeze-thaw durability can have an indicative nature in the assessment of the usefulness of selected aggregates for constructing drainage layers. The conducted studies indicate that the deciding parameter when selecting an aggregate ought to be its hydraulic conductivity, determined accounting for the changes taking place in the freeze-thaw cycles. The equations of changes in the conductivity of aggregates indicated by the authors make it possible to assess them for practical purposes.