Wyniki wyszukiwania - BazTech

1

Moisture content of peat-moorsh soils with special attention to periods of drought

Oleszczuk Ryszard, Jadczyszyn Jan, Urbański Janusz, Zając Ewelina, Brandyk Andrzej, Niedźwiecki Jacek

Journal of Water and Land Development

|

2023

|

no. 59

234--247

EN

The paper presents the course of variability of the moisture content of the top layers in shallow (45 cm) and medium-deep (90 cm) peat-moorsh soil profiles in the years 2015-2019 against the background of the same meteorological conditions and a similar level of the groundwater table. The relative precipitation index (RPI) classifies the years 2015 and 2016 as dry, 2017 as wet, and 2018 and 2019 as average. For periods of atmospheric droughts, the average daily climatic water balance (CWB) ranged from -5.30 to -1.35 mm∙d-1. The water table did not fall below 90 cm b.g.l. during the entire study period, and the range of its fluctuations was 8 cm greater in the shallow than in the medium-deep profile. The range of moisture at different depths varied significantly and ranged from approx. 6% in periods of drought to about 80% in wet periods. Soil moisture throughout the measurement period was above the plant available water range (pF > 4.2). The occurrence of soil drought in the shallow peat-moorsh soil profile had a range of up to 40 cm, and in the medium-deep profile of up to 30 cm. The sequence of no-precipitation days and the maximum amount of daily evapotranspiration during them determine the possible timing of drought; however, it is the precipitation distribution in individual months, considered in the current CWB values, that ultimately determine the formation of soil water resources at the research site.

2

Estimation of Organic Soils Subsidence in the Vicinity of Hydraulic Structures – Case Study of a Subirrigation System in Central Poland

Brandyk Andrzej, Oleszczuk Ryszard, Urbański Janusz

Journal of Ecological Engineering

|

2020

|

Vol. 21, nr 8

64--74

EN

The consequences of organic soil subsidence gained considerable importance in a wide range of scientific literature. Since most of the works focused mainly on the subsidence of the land surface, less attention was paid to the effects on hydraulic structures, either to their malfunctioning or to the proper management of the subirrigation systems. For the reasons mentioned above, the paper considers the selected technical parameters (underground pipelines covering thickness and soil subsidence behind inlet and outlet protections) of 37 culverts (communication structures) and 42 culvert-gates (communication and water damming). All the structures were located within the area of a subirrigation system on the previously drained organic soils (Solec system, Mazovian Voivodship, 30 km south of Warsaw). They underwent field measurements of the pipelines covering subsidence and land surface lowering behind their protections on the left and right side of the inlet and outlet section. The achieved results were confronted with the adopted limit and admissible values. Due to the progressing congestion and subsidence of organic soil, the covering thickness of pipelines did not exceed the limit value for 38.5% of the culverts and 36% of culvert-gates. From a long-term perspective (1971–2014) the average subsidence rates in the vicinity of the structures and surrounding peatland surface were found as comparable, ranging from 0.63 to 0.83 cm/year. Particular attention was paid to the influence of water damming that was evident for the inlet sections of culvertgates showing considerably lower subsidence and damage degree.

3

Ocena tempa osiadania odwodnionego torfowiska oraz weryfikacja równań empirycznych opisujących ten proces

Gąsowska Monika, Oleszczuk Ryszard, Urbański Janusz

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

|

2019

|

Vol. 28, No. 1

95--104

PL

W pracy przedstawiono ocenę tempa zanikania fragmentu odwodnionego dolinowego złoża torfowego w latach 1978–2015. Zaobserwowano bardzo duże zróżnicowanie tego zjawiska na relatywnie małej badanej powierzchni (ok. 15 ha) wynoszące od 0,06 do 1,56 cm·rok–1. Procentowy ubytek miąższości złoża torfowego w latach 1978–2015 na analizowanym obszarze był zróżnicowany i nie zależał od początkowej miąższości złoża torfowego. Wahał się on w granicach od 2 do około 44%. Uzyskane dane pomiarowe umożliwiły weryfikację dostępnych w literaturze wybranych równań empirycznych opisujących proces osiadania. Umożliwiło to zarekomendowanie wybranych równań do stosowania w przypadku przewidywania wielkości tempa osiadania dla podobnych odwodnionych gleb organicznych.

EN

The papers presents the soil surface subsidence rate of drained (1967–1971) peat deposit in 1978–2015 years. The very high differences of the rate was observed on relatively small area (15 ha). The subsidence rate was observed in the range from 0.06 to 1.56 cm·year–1. The percentage loss of the peat deposit thickness in the years 1978–2015 in the analyzed area was varied and did not depend on the initial thickness of the peat deposit. It oscillated between 2 and approx. 44%. The obtained measured data were able to perform the verifi cation of selected published in the literature empirical equations to predict the subsidence rate of soil surface of drained many years ago lowland peatlands.