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Effects of Different Irrigation Strategies on Soil Water, Salt, and Nitrate Nitrogen Transport

Abstract

Intermittent irrigation has attracted much attention as a water-saving technology in arid and semi-arid regions. For understanding the effect of intermittent irrigation on water and solute storage varied from irrigation amount per time (IRA), irrigation application frequency (IRAF), irrigation intervals (IRI) and even soil texture (ST), intermittent irrigation experiment was carried out in 33 micro-plots in Inner Mongolia, China. The experiment results were used for the calibration and validation of HYDRUS-1D software. Then 3 ST (silty clay loam, silty loam, and silty clay), 5 IRA (2, 4, 6, 8, and 10 cm), 4 IRAF (2, 3, 4, and 5 times) and 4 IRI (1, 2, 3, and 4 days) were combined and total 240 scenarios were simulated by HYDRUS-1D. Analysis of variance (ANVOA) of simulated results indicated that ST, IRA, and IRAF had significant effect on salt and nitrate nitrogen (NO3 -N) storage of 0-40 cm depth soil in intermittent irrigation while only ST affected soil water storage obviously. Furthermore, salt leaching percentage (SLP) and water use efficiency (WUE) of 0-40 cm depth were calculated and statistical prediction models for SLP were established based on the ANOVA using multiple regression analysis in each soil texture. Then constraint conditions of soil water storage (around field capacity), salt storage (smaller than 168 mg·cm−2), WUE (as large as possible) in 0-40 cm depth and total irrigation water amount (less than 25 cm) were proposed to find out the optimal intermittent irrigation strategies. Before sowing, the optimal irrigation strategy for silty clay loam soil was 6 cm IRA, 3 times IRAF, and 2 days IRI respectively. For silty loam and silty clay soils, IRA, IRAF, and IRI were 8 cm, 3 times, and 2 days respectively.

Open access
Effects of Foliar Application of Titanium on Seed Yield in Timothy (Phleum pratense L.)

Abstract

Titanium is one of a plant biostimulators. It stimulates life processes, growth and development, as well as affects physiological and biochemical pathways, often increasing biomass production and enhancing yield. An open field experiment was conducted in the years 2011-2013 in Polanowice, Poland to investigate the effects of titanium foliar fertilization on the growth of timothy grass (Phleum pratense L.). This single-factor, randomized block design study was performed in four replicates on research plots with the area of 10 m2 each. The substrate was black loess soil (chernozem) typical for top class farmland. Titanium fertilization via leaf spray was performed with a water solution of Tytanit® at three doses of 0.2, 0.4, and 0.8 dm3 · ha−1. Foliar fertilization with the highest dose of Tytanit® significantly increased seed yield, thousand grain weight and germination capacity. Moreover, the middle dose of Tytanit® (0.4 dm3 · ha−1) was enough to observe a positive effect on the sample.

Open access
Environmental Impact of Exploration from Unconventional Gas Deposits in Poland

Abstract

Shale formations have been recently treated only as source rocks and sealing packages mainly of conventional deposits. At present shales, which have a considerable concentration of highly mature organic matter appearing in complexes of over 30 m thick are used as unconventional sources for natural gas production with the use of advanced drilling technologies. Natural gas production in such rock formations necessitates performing a horizontal section in the borehole and a big number of hydraulic fracturing jobs. The unconventional shale gas deposits have been prospected also in Poland for a couple of years. Exploration works mainly concentrate on a vast area passing from Pomerania through Mazowsze to the Lublin region in Poland. The analysis of the geologic analyses reveals that the most perspective are shales in the Lower Paleozoic at a depth of 2500 m in the eastern part to about 4000 m in the western part of the area. The paper is focused on the quantitative and qualitative evaluation of environmental impact of natural gas exploration works from unconventional deposits. Special attention was paid to the hydraulic fracturing jobs in shales, which create particular hazard for water and soil environment. These hazards already appear at the stage of preliminary works, when big quantities of chemicals and water for frac jobs are stored in the rig area, and then, during realization of works, when the spent hydraulic fracturing fluid may penetrate the water-bearing horizons in the caprock. The composition of fracturing fluid used in Gapowo B-1A well are given along with the results of chemical analyses of a few parts of spent fracturing fluid samples pumped out from the borehole. The fluid turned out to be high in salt (high specific electrolyte conductance (SEC) and total dissolved substances (TDS) and a high toxicity for most of the living organisms). For this reason the spent fracturing fluid should not enter the environment without control.

Open access
Ethanol Recovery from Low-Concentration Aqueous Solutions Using Membrane Contactors with Ionic Liquids

Abstract

Recovery of alcohols from diluted aqueous solutions is highly energy-intensive. In order to reduce the costs of concentration of alcohols, membrane processes (including membrane extraction) are used. This paper reports the results of ethanol concentration from diluted aqueous solutions using a hollow fiber membrane contactor with ionic liquid. The studies were performed using a contactor with microporous hollow fiber membranes. The membrane creates a barrier between the feed and extracting solvent, also providing a large mass transfer area. In the process, selected ionic liquid presenting different selectivity towards ethanol was used as extractant. The experiments were performed with feed concentrations of ethanol ranging from 1 to 5 wt.% and various feed flow rates ranging from 1 to 8 dm3/h.

Open access
Evaluation of the Contact Angle of Hydrophobised Lightweight-Aggregate Concrete with Sewage Sludge

Abstract

The aim of the research presented in the paper was to evaluate the feasibility of using hydrophobic preparations based on organosilicon compounds for protection treatment of lightweight aggregates modified with municipal sewage sludge. Issues related to the wettability of the surface layer of hydrophobised lightweight-aggregate concrete supplemented with sewage sludge are discussed in the paper. The experimental part of the study is focused on the physical and mechanical characteristics of lightweight-aggregate concrete and the effect of two hydrophobic preparations on the contact angle of the material. The contact angle for lightweight concrete (θw) was determined as a function of time using one measurement liquid. The hydrophobic coatings in the structure of lightweight concrete modified with sewage sludge were shown using electron microscopy. The investigations demonstrated the effectiveness of hydrophobisation of porous lightweight concretes. On the hydrophobic surfaces, the contact angles decreased with time and depended on the preparations used. The results of the research confirm the possibility to produce lightweight aggregate-concretes modified with sewage sludge with appropriate surface protection against external moisture.

Open access
Impact of Flowback Water on Activated Sludge Biocenosis During Municipal Wastewater Treatment

Abstract

The aim of this study was to determine the effect of flowback water on an activated sludge biocenosis during municipal wastewater treatment in the sequencing batch reactors (SBRs). Two series were performed. In series 1, only municipal wastewater was treated, whereas in series 2, municipal wastewater with pre-treated flowback water was used. Flowback water constituted 3-5% of the influent and was introduced to the SBRs twice per week. Introducing flowback water did not decrease the quality of effluent from the SBRs. However, the composition of the activated sludge biocenosis differed between series, ie the biodiversity of protozoa and the relative abundance of microfauna in functional groups changed after flowback water addition. Polymerase chain reaction - denaturing gradient gel electrophoresis (PCR-DGGE) showed that the ammonia oxidizers community responded faster to flowback water addition than the total bacterial community and remained relatively stable during treatment. However, after 9 weeks of exposure to flowback water, ammonia oxidizing bacteria (AOB) biodiversity decreased. This suggests that prolonged exposure could cause nitrification problems, leading to deterioration in effluent quality

Open access
Low Impact Development Practices: A Review of Current Research and Recommendations for Future Directions

Abstract

A low impact development (LID) is an alternative land development approach for managing stormwater that has been recommended instead of the traditional stormwater design. The main purpose of LID is to reduce the impact of development on water related problems through the use of stormwater management practices that infiltrate, evaporate, or harvest and use stormwater on the site where it falls. In recent years, more research has been carried out on the individual practice of LID such as bioretention, pervious pavements, rain garden and grassed swales. Nowadays LID practices have been successfully used to manage stormwater runoff, improve water quality, protect the environmental and hydrological aspects of the developed areas. Bioretention cells have been effectively used in retaining large volumes of runoff and pollutants on site. Pervious pavements have been extremely effective practice in infiltrating stormwater runoff as early as possible as rain fall on site and store a large quantity of water. Nowadays, sand ditch a new water harvesting technique is used that significantly reduces runoff and sediment losses and increases infiltration and soil loss. This paper highlights evidence in the literature regarding the beneficial uses of LID practices and encourage to adopt these practices for environmental friendly construction and sustainable development in the world.

Open access
Modified Description of Soil Processes vs. Quality of Numerical Weather Forecasts - “Bare Soil” Case

Abstract

Soil and atmosphere boundary layer (ABL) interact with each other and influence on physical processes in soil and atmosphere. Current parameterization of soil physical processes in TERRA_ML (multilayer soil module of COSMO meteorological model) was prepared more than 40 years ago and did not give satisfactory forecast results. New parameterizations should involve physical processes in the soil (microphysics processes in soil, fluid dynamics in porous media, soil dynamics, etc.), water cycle in soil and soil-plant-water relation. The aim of this project was to improve current soil parameterization in the COSMO model, called “TERRA_ML”. The results of the work, related to the parameterization of physical processes of bare soil evaporation, vertical and horizontal water transport in soil and a runoff from soil layers, are presented in this paper. In order to eliminate underestimation of evaporation from soil in the afternoon and overestimation evaporation from soil in the morning a correction time-depending factor was also introduced. In this way, theoretical description of vertical water transport in soil is improved with temperature dependency of hydraulic diffusivity for different sort of soil.

Open access
New Indices Determining Heavy Metals Migration in a Sewage Sludge

Abstract

The four step procedure developed by the European Community Bureau of Reference (BCR) is the optimum means of identifying heavy metal fractions in sewage sludge samples. Using the BCR procedure enables to get the date basing on which one can calculate metal stability index which supplies information on the strength of metal bonds with mineral organic soil components. Unfortunately, very popular formulae describing this index do not possess any theoretical justification and do not generate all values in the range of [0; 1]. Hence, in this paper one has presented new formulae describing not only the stability index but also a strictly connected with it the mobility index. In addition, one has suggested that these new formulae depend on the Equivalent Population (EP) indicator.

Open access
Ozone Concentration at Ground Level Depending on the Content of NOx and Meteorological Conditions

Abstract

This study analyzed the temporal variation of tropospheric ozone (O3) in Poznan (midwestern Poland) on the basis of data collected from a State Environmental Monitoring air quality assessment station. The aim was to investigate the distribution and variation of O3 levels and to assess the relationship with nitrogen oxides (NOx) and meteorological conditions. These relationships were assessed by multiple regression analysis and cluster analysis. The O3 levels showed a high annual, seasonal and daily volatility, and were significantly influenced by meteorological conditions and NOx levels. High O3 levels were accompanied by above-average levels of radiation (Rad), air temperature (Ta) and wind speed (Ws), together with below-average values of NOx and humidity (Rh). Atmospheric pressure (Ph) had an ambiguous effect on O3 levels.

Open access