The study was carried out in a raised bog located in the Kamanos state reserve in northwestern Lithuania (56°16'N, 22°39'W). The area of the raised bog is 1722 ha. To assess the effect of ...meteorological factors and damming of drainage ditches on the water regime of the Kamanos mire, we have analysed the water table depth fluctuations over the last 22 years in the northern part of the mire, which was drained out in 1907, and the drainage ditch was dammed in 1999. The control plots were established in the central part of the raised bog without draining activities, where Eriophorum va‐ginatum‐Sphagnum spp. communities prevail in the ground vegetation and small Scots pine trees may also be found.
The results showed that, in both natural and damaged‐by‐drainage sites of the raised bog, the air moisture deficiency and the amount of precipitation had a significant effect on the fluctuation of the water table depth during the growth period (R = 0.416 - 0.761 p < 0.05). In comparison with the control plots, in 7 years after establishing dams in a 0.9–1.2 m deep ditch, the groundwater table increased by 9.8 to 12.2 cm in the area up to 980 m apart from the ditch. After damming the ditches in the extensively and intensively drained parts of the raised bog, the levelling out of the water table to a similar depth as in the control plots, occurred within 4 years and is forecasted to occur within 12 years, respectively. The water table of the drained sites of the raised bog was more sensitive to increasing annual temperatures than the water table in the undrained sites of the raised bog.
Santrauka
Tyrimai buvo atlikti Kamanų valstybinio gamtinio rezervato aukštapelkėje (56º16´N, 22º39´W), kuri yra šiaurės vakarų Lietuvoje. Aukštapelkės plotas – 1722 ha. Tam, kad būtų įvertinta meteorologinių faktorių bei griovių tvenkimo įtaka Kamanų pelkės hidrologijai, buvo išanalizuotos gruntinių vandenų slūgsojimo lygio fluktuacijos per pastaruosius 22 metus – 1907 m. nusausintoje ir 1999 m. patvenktoje šiaurinėje pelkės dalyje. Kontroliniai plotai išskirti centrinėje nesausintoje aukštapelkės dalyje. Čia vyrauja Eriophorum vaginatum-Sphagnum spp. (kupstinio švylio-kiminų) bendrijos su žemaūgėmis pušelėmis. Nustatyta, kad pagrindiniai meteorologiniai veiksniai, veikiantys vegetacijos periodo gruntinių vandenų fluktuacijas tiek natūraliuose, tiek sausinimu pažeistuose Kamanų aukštapelkės plotuose, yra oro drėgmės deficitas ir krituliai (R 2 = 0,416 – 0,761 p < 0,05). Per 7 metų periodą, praėjusį po 0,9–1,2 m gylio griovio, sausinusio aukštapelkę 92 m. blokavimo užtvaromis (1999 m.), gruntinių vandenų lygis 980 m pločio pagriovio zonoje, palyginus su kontrole, pakilo vidutiniškai 9,8–12,2 cm. Gruntinių vandenų atsistatymas iki kontrolinio lygio, blokavus griovius užtvaromis ekstensyviai nusausintose pelkės dalyse, įvyko per 4 metus, o intensyviai nusausintoje aukštapelkės dalyje, kaip rodo prognozės, įvyks apytiksliai per 12 m. Išaiškinta, kad į klimato šiltėjimą, t. y. į metinių temperatūrų didėjimą, nusausintų pelkių gruntiniai vandenys reaguoja labiau negu nenusausintų.
Резюме
Гидрологические исследования были проведены на верховом болоте государственного заповедника Каманос (56º16´N, 22º39´W), который находится на северо-западе Литвы. Площадь верхового болота – 1722 га. Целью работы было установить влияние метеорологических факторов и уничтожения осушительных канав на гидрологический режим верхового болота. Исходным материалом послужили данные о динамике уровня грунтовых вод за последние 22 года на в 1907 г. осушенных и в 1999 г. вновь затопленных площадях заповедника с болотными почвами. Контрольными площадями послужили нетронутые осушением участки болота, выделенные в центральной части заповедника, где преобладают сообщества пушицы и белого мха (Eriophorum vaginatum – Sphagnum spp.) с низкорослой сосной. Выявлено, что за 7-летний период, прошедший после уничтожения в 1999 г. осушительных канав глубиной 0,9–1,2 м, уровень грунтовых вод на приканавной полосе, равной 980 м, повысился в среднем на 9,8–12,2 см по сравнению с контрольным уровнем. Восстановление уровня грунтовых вод (до контрольного уровня) после уничтожения канав на экстенсивно осушенных площадях происходит спустя 4 года, а на интенсивно осушенных площадях – спустя 12 лет. Установлено, что на потепление климата, т. е. на повышение годовых температур, сильнее реагируют грунтовые воды осушенных болот, чем неосушенных.
The study was carried out in a raised bog located in the Kamanos state reserve in northwestern Lithuania (56°16'N, 22°39'W). The area of the raised bog is 1722 ha. To assess the effect of ...meteorological factors and damming of drainage ditches on the water regime of the Kamanos mire, we have analysed the water table depth fluctuations over the last 22 years in the northern part of the mire, which was drained out in 1907, and the drainage ditch was dammed in 1999. The control plots were established in the central part of the raised bog without draining activities, where Eriophorum va‐ginatum‐Sphagnum spp. communities prevail in the ground vegetation and small Scots pine trees may also be found. The results showed that, in both natural and damaged‐by‐drainage sites of the raised bog, the air moisture deficiency and the amount of precipitation had a significant effect on the fluctuation of the water table depth during the growth period (R = 0.416 ‐ 0.761 p < 0.05). In comparison with the control plots, in 7 years after establishing dams in a 0.9–1.2 m deep ditch, the groundwater table increased by 9.8 to 12.2 cm in the area up to 980 m apart from the ditch. After damming the ditches in the extensively and intensively drained parts of the raised bog, the levelling out of the water table to a similar depth as in the control plots, occurred within 4 years and is forecasted to occur within 12 years, respectively. The water table of the drained sites of the raised bog was more sensitive to increasing annual temperatures than the water table in the undrained sites of the raised bog. Santrauka Tyrimai buvo atlikti Kamanų valstybinio gamtinio rezervato aukštapelkėje (56º16´N, 22º39´W), kuri yra šiaurės vakarų Lietuvoje. Aukštapelkės plotas – 1722 ha. Tam, kad būtų įvertinta meteorologinių faktorių bei griovių tvenkimo įtaka Kamanų pelkės hidrologijai, buvo išanalizuotos gruntinių vandenų slūgsojimo lygio fluktuacijos per pastaruosius 22 metus – 1907 m. nusausintoje ir 1999 m. patvenktoje šiaurinėje pelkės dalyje. Kontroliniai plotai išskirti centrinėje nesausintoje aukštapelkės dalyje. Čia vyrauja Eriophorum vaginatum-Sphagnum spp. (kupstinio švylio-kiminų) bendrijos su žemaūgėmis pušelėmis. Nustatyta, kad pagrindiniai meteorologiniai veiksniai, veikiantys vegetacijos periodo gruntinių vandenų fluktuacijas tiek natūraliuose, tiek sausinimu pažeistuose Kamanų aukštapelkės plotuose, yra oro drėgmės deficitas ir krituliai (R 2 = 0,416 – 0,761 p < 0,05). Per 7 metų periodą, praėjusį po 0,9–1,2 m gylio griovio, sausinusio aukštapelkę 92 m. blokavimo užtvaromis (1999 m.), gruntinių vandenų lygis 980 m pločio pagriovio zonoje, palyginus su kontrole, pakilo vidutiniškai 9,8–12,2 cm. Gruntinių vandenų atsistatymas iki kontrolinio lygio, blokavus griovius užtvaromis ekstensyviai nusausintose pelkės dalyse, įvyko per 4 metus, o intensyviai nusausintoje aukštapelkės dalyje, kaip rodo prognozės, įvyks apytiksliai per 12 m. Išaiškinta, kad į klimato šiltėjimą, t. y. į metinių temperatūrų didėjimą, nusausintų pelkių gruntiniai vandenys reaguoja labiau negu nenusausintų. Резюме Гидрологические исследования были проведены на верховом болоте государственного заповедника Каманос (56º16´N, 22º39´W), который находится на северо-западе Литвы. Площадь верхового болота – 1722 га. Целью работы было установить влияние метеорологических факторов и уничтожения осушительных канав на гидрологический режим верхового болота. Исходным материалом послужили данные о динамике уровня грунтовых вод за последние 22 года на в 1907 г. осушенных и в 1999 г. вновь затопленных площадях заповедника с болотными почвами. Контрольными площадями послужили нетронутые осушением участки болота, выделенные в центральной части заповедника, где преобладают сообщества пушицы и белого мха (Eriophorum vaginatum – Sphagnum spp.) с низкорослой сосной. Выявлено, что за 7-летний период, прошедший после уничтожения в 1999 г. осушительных канав глубиной 0,9–1,2 м, уровень грунтовых вод на приканавной полосе, равной 980 м, повысился в среднем на 9,8–12,2 см по сравнению с контрольным уровнем. Восстановление уровня грунтовых вод (до контрольного уровня) после уничтожения канав на экстенсивно осушенных площадях происходит спустя 4 года, а на интенсивно осушенных площадях – спустя 12 лет. Установлено, что на потепление климата, т. е. на повышение годовых температур, сильнее реагируют грунтовые воды осушенных болот, чем неосушенных. First Published Online: 14 Oct 2010 Reikšminiai žodžiai: gruntinio vandens lygis, griovių blokavimas užtvaromis, hidrologija, meteorologiniai veiksniai, pelkė. Ключевые слова: уровень грунтовых вод, уничтожение канав, гидрология, метеорологические факторы, болотo.
The study was carried out in a raised bog located in the Kamanos state reserve in northwestern Lithuania (56°16'N, 22°39'W). The area of the raised bog is 1722 ha. To assess the effect of ...meteorological factors and damming of drainage ditches on the water regime of the Kamanos mire, we have analysed the water table depth fluctuations over the last 22 years in the northern part of the mire, which was drained out in 1907, and the drainage ditch was dammed in 1999. The control plots were established in the central part of the raised bog without draining activities, where Eriophorum va-ginatum-Sphagnum spp. communities prevail in the ground vegetation and small Scots pine trees may also be found.
The results showed that, in both natural and damaged-by-drainage sites of the raised bog, the air moisture deficiency and the amount of precipitation had a significant effect on the fluctuation of the water table depth during the growth period (R = 0.416 - 0.761 p < 0.05). In comparison with the control plots, in 7 years after establishing dams in a 0.9-1.2 m deep ditch, the groundwater table increased by 9.8 to 12.2 cm in the area up to 980 m apart from the ditch. After damming the ditches in the extensively and intensively drained parts of the raised bog, the levelling out of the water table to a similar depth as in the control plots, occurred within 4 years and is forecasted to occur within 12 years, respectively. The water table of the drained sites of the raised bog was more sensitive to increasing annual temperatures than the water table in the undrained sites of the raised bog.
The study was carried out in a raised bog located in the Kamanos state reserve in northwestern Lithuania (56 deg 16'N, 22 deg 39'W). The area of the raised bog is 1722 ha. To assess the effect of ...meteorological factors and damming of drainage ditches on the water regime of the Kamanos mire, we have analysed the water table depth fluctuations over the last 22 years in the northern part of the mire, which was drained out in 1907, and the drainage ditch was dammed in 1999. The control plots were established in the central part of the raised bog without draining activities, where Eriophorum vaginatum-Sphagnum spp. communities prevail in the ground vegetation and small Scots pine trees may also be found. The results showed that, in both natural and damaged-by-drainage sites of the raised bog, the air moisture deficiency and the amount of precipitation had a significant effect on the fluctuation of the water table depth during the growth period (R2 = 0.416 - 0.761 p < 0.05). In comparison with the control plots, in 7 years after establishing dams in a 0.9-1.2 m deep ditch, the groundwater table increased by 9.8 to 12.2 cm in the area up to 980 m apart from the ditch. After damming the ditches in the extensively and intensively drained parts of the raised bog, the levelling out of the water table to a similar depth as in the control plots, occurred within 4 years and is forecasted to occur within 12 years, respectively. The water table of the drained sites of the raised bog was more sensitive to increasing annual temperatures than the water table in the undrained sites of the raised bog.
During the pandemic, distance learning gained its necessity. Most schools and universities were forced to use e-learning tools. The fast transition to distance learning increased the digitalization ...of the educational system and influenced the increase of security incident numbers as there was no time to estimate the security level change by incorporating new e-learning systems. Notably, preparation for distance learning was accompanied by several limitations: lack of time, lack of resources to manage the information technologies and systems, lack of knowledge on information security management, and security level modeling. In this paper, we propose a security level estimation model for educational organizations. This model takes into account distance learning specifics and allows quantitative estimation of an organization’s security level. It is based on 49 criteria values, structured into an AHP (Analytic Hierarchy Process) tree, and arranged to final security level metric by incorporating experts’ opinion-based criteria importance coefficients. The research proposed a criteria tree and obtained experts’ opinions lead to educational organization security level evaluation model, resulting in one quantitative metric. It can be used to model different situations and find the better alternative in case of security level, without external security experts usage. Use case analysis results and their similarity to security experts’ evaluation are presented in this paper as validation of the proposed model. It confirms the model meets experts-based information security level ranking, therefore, can be used for simpler security modeling in educational organizations.
The interest in potential applications produced with self-compacting fibre reinforced concrete continues to grow, but in practice, problems associated with an uneven distribution and orientation of ...fibres in the concrete structure occur. It is not clear what exactly influences uneven distribution of fibres in self-compacting concrete (SCC) mixtures, especially during the casting and how different factors influence fibre orientation. The objective of this work was to investigate how rheological properties influence the steel fibre distribution in self-compacting concrete. This work also focuses on the investigation of steel fibre spatial orientation dependence on rheological properties of SCC, while keeping other casting parameters and the proportions of mixture components constant. Mixtures with three different rheological properties were chosen based on slump flow, slump flow time
t
500
and static segregation values. The steel fibre orientation, volumetric concentration and spatial distribution values were determined in separate beam sections using three different non-destructive testing methods: electromagnetic induction, image analysis and computed tomography (CT scan). The comparison of the results is presented. The results show how different rheological properties of SCC affect the steel fibre orientation and distribution for the case of beams produced with the flow-induced casting method.
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