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Effect of Tree Shelters and Regeneration Method on Survival and Growth of Cork Oak Plantations in the Maamora Forest, Morocco

El Alami Sanae Lahlimi, El Aboudi Ahmed, El Antry Salwa, El Mnouar El Ayyachi, Dallahi Youssef, Rabhi Ameur

Journal of Ecological Engineering

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2023

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Vol. 24, nr 7

360--374

EN

Forests are under intense human pressure, hindering their restoration. A potential solution to regeneration problems is the adoption of tree shelters, which have demonstrated protective benefits in the early establishment of forest plantations. A 9-year study was conducted in the Maamora forest (Morocco) to evaluate the effects of tube shelters and regeneration methods (direct seeding and seedling) on the growth and survival of cork oak (Quercus suber) plantations. A split-plot design was developed with three replicates of 36 plants for each of the four shelter treatments, including T0 (control), T1 (Tubex 1.20 m), T2 (Tubex 1.50 m), and T3 (Tubex 1.80 m) for a total of 964 plants, where periodic inventories were conducted to assess plant survival and growth. Our results show regeneration methods and shelters significantly influenced the survival of cork oak. Direct-seeded plants were more successful than those from seedlings, presenting survival rates of up to 97%. Despite a minimal shelter effect at the beginning, their positive influence was strong later on. Only plants installed with the 1.20 m shelter had an overall success rate of over 50%. Regeneration method had a strong influence on height and diameter growth, with seedling units showing taller plants initially, which shifted to direct-seeded plants in subsequent years. Conversely, the effect of shelters on growth parameters was generally non-significant. Nonetheless, sheltered trees exhibited greater height and diameter than unsheltered trees, particularly in the latter years. Sheltered plants showed an overall faster rate of vertical growth, while unsheltered plants showed faster radial growth.

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Decision-making model using the Analytical Hierarchy Process for the selection of the type of concrete and the method of its maintenance in dry, hot climate conditions

Hsino Mahmoud, Jasiczak Józef

Archives of Civil Engineering

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2023

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Vol. 69, nr 3

385--403

EN

The article presents selected types of phase change materials (PCM) and their properties in terms of applications in construction and concrete technology. The purpose of using PCM is to allow the technological barrier to be exceeded in hot and dry climate conditions, enabling the construction of non-cracking concrete structures. Methodology of the multi-criteria decision-making process with the use of a relatively new decision-making tool in construction - the Analytical Hierarchical Process (AHP) is presented. Theoretical aspects of the method and an example of its practical use for the selection of the best material variant and concrete care method in the dry Syrian climate are presented. The conclusions resulting from the presented article concern two areas, i.e. the advisability of using phase change materials for temperature regulation in the maturing fresh concrete in dry climate conditions and the attractiveness of the AHP method justifying the advisability of choosing the maintenance methods in such conditions.

PL

W artykule przedstawiono wybrane rodzaje materiałów zmiennofazowych (PCM) oraz ich właściwości pod kątem zastosowań w budownictwie, w tym w technologii betonu. Celem stosowania PCM jako dodatku do świeżego betonu jest umożliwienie przekroczenia określonych barier technologicznych występujących w warunkach klimatu gorącego i suchego, gwarantując schładzanie betonu i tym samym wykonanie niezarysowanych konstrukcji betonowych. Przedstawiono metodologię wielokryterialnego procesu decyzyjnego związanego z wyborem różnych wariantów pielęgnacji betonu w warunkach ekstremalnie suchych z wykorzystaniem stosunkowo nowego narzędzia decyzyjnego w budownictwie jakim jest AHP tj. Analytic Hierarchy Process. Przedstawiono teoretyczne aspekty metody oraz przykład jej praktycznego zastosowania do wyboru najlepszego rodzaju cementu oraz betonu i metody jego pielęgnacji w suchym klimacie syryjskim. Wnioski płynące z przedstawionego artykułu dotyczą dwóch obszarów, tj. celowości stosowania materiałów PCM z przemianą fazową o stosunkowo niskiej temperaturze do regulacji temperatury w dojrzewającym świeżym betonie w suchych warunkach klimatycznych oraz atrakcyjności metody AHP uzasadniającej celowość wyboru alternatywnych metod pielęgnacji młodego betonu w takich warunkach.

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Suitable sites identifcation for potential rainwater harvesting (PRWH) using a multi criteria decision support system (MCDSS)

Radwan Farid, Alazba Abdulrahman Ali

Acta Geophysica

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2023

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Vol. 71, no. 1

449--468

EN

The world today faces water scarcity issues, especially in developing countries. This situation is further aggravated under arid and semiarid climates with the water demand increasing and limited rainfall events. The study was conducted in the Riyadh metropolitan area of Saudi Arabia. The study area has a hot arid desert climate. Therefore, there is an urgent need for harvesting rainwater to confront the increasing water demand. This research aims to identify the potential rainwater harvesting (PRWH) suitable sites based on the multi-criteria decision support system by the spatial analytic hierarchy process, with the aid of the integration of geographic information systems and remote sensing techniques. Mapping PRWH was carried out using the thematic layers of the slope, soil texture, land use and land cover (LULC), precipitation, and potential runoff coefficient (PRC). The study findings revealed that Riyadh has four hydrologic soil groups (HSGs), namely A, B, C, and D groups, and the percentage area is 2%, 26%, 3%, and 71%, respectively. The slope classes are fat (8–15%), moderately steep (>15–30%), and mountainous (>30%). The LULC layers are barren lands, agricultural lands, urban, and roads. The precipitation has been distributed into five classes namely very low (5.9%), low (10.1%), medium (13.2%), high (13.5%), and very high (57.3%) of the total investigated area. The PRC values were distributed in five levels namely very low (0.3–0.5), high (>0.5–0.7), and very high (>0.7–1), where about 83% of the capital faces high and very high PRC values. The percentage area of PRWH suitability sites is unsuitable (0.4%), poor (0.8%), moderate (13.3%), good (47.5%), and excellent (38%) of the total entire area. More than 85% of Riyadh has good and excellent suitability for PRWH. This study is tantamount to a powerful tool for identifying the PRWH suitability sites in arid and semiarid regions to confront the water demand increase.

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Validity, reliability and certainty of PERSIANN and TRMM satellite-derived daily precipitation data in arid and semiarid climates

Khojand Keyvan, Shaghaghian Mahmood Reza, Ghadampour Zahra, Sabzevari Touraj

Acta Geophysica

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2022

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Vol. 70, no 4

1745--1767

EN

Having doubts about the adequacy of reliability level of satellite-derived precipitation products, along with their application in large number of hydrological models, has led to many studies on evaluating the efficiency of such data. In this study, two new procedures were proposed to compute reliability and certainty degrees of PERSIANN and TRMM 3B42RT data sets, and six traditional indicators were used to evaluate their validation. In addition, the cumulative density function (cdf) of the above-mentioned data sets was compared with the ground-based observations in 23 synoptic stations in Fars, Iran. The Kolmogorov–Smirnov test was performed using the data sets at 5% significance level which led to the result of null hypothesis that was not being rejected, suggesting that the satellite-derived daily precipitation data (SDDPD) and ground based observations are drawn from the same distribution. Results indicated that TRMM and PERSIANN follow quite similar probability pattern of ground-based observations in arid and semiarid climate, respectively. However, data probability pattern of TRMM cannot be considered similar to ground-based observations in arid region, neither can PERSIANN in semiarid climate. Among common cross-validating attributes, the values of ME and BIAS, in addition to RMSE and MAE, led to the conclusion that in PERSIANN, the rainfall daily rates are almost underestimated while TRMM overestimates the values mainly in semiarid regions. Moreover, the PERSIANN was found to be significantly correlated with IDM (De Martonne aridity Index), and the values of underestimation increased with growth of the index. The reliability values of SDDPD over the study area, for both TRMM and PERSIANN, show the reverse trend with increasing IDM in almost all acceptable error intervals. Along with effects of climate conditions, the reliability degrees of PERSIANN seem quite more consistent at different acceptable error intervals in comparison with the corresponding values of TRMM. In addition to validity and reliability, the error entropy of SDDPD, as an index for uncertainty degree, increases as the IDM rises, which is theoretically corresponds with reliability concept. However, in comparison with PERSIANN, TRMM data set, overall, has higher degree of uncertainty. In addition, to evaluate effect of daily rainfall intensity on the uncertainty degree of SDDPD, the uncertainty degree slightly increases as daily rainfall intensifies to about 15 mm/day. But for higher daily rainfall intensities, on the other hand, the uncertainty degree seems to gradually decline as the daily rainfall increases.

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Fluvial sedimentation of sandy deposits of the Słupiec Formation (Middle Rotliegendes) near Nowa Ruda (Intra-Sudetic Basin, SW Poland)

Kurowski L.

Geologia Sudetica

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2004

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Vol. 36

21-38

EN

The sandy sediments described in this paper are the lower, approximately 400-meter-thick part of the Słupiec Formation, which is part of lower Permian clastic deposits in the Intra-Sudetic Basin. At their base, the sandy deposits of the Słupiec Formation are bounded by fine-grained lacustrine sediments known as the Upper Anthracosia Shale (Krajanów Formation); upwards, they pass into the Walchia Shale (the upper part of the Słupiec Formation), also regarded to be of lacustrine origin. These sandstones consist chiefly of sublithic to subarkosic arenites and wackes. In places, polymictic conglomerates and fine-grained sediments, and also sublithic to subarkosic mudstones occur. These sediments form a structurally varied facies assembly, presumably fluvial in origin. An analysis of the vertical sequence of lithofacies revealed a distinct tendency towards the formation of simple cyclical sequences with the grain fining upwards and with a distinctly expressed asymmetry in favour of 'high-energy' medium- and coarse-grained facies. The oscillation tendency was marked only in 'low-energy' fine facies, which are sparsely represented in the sequence. The paleochannel analysis yielded results compatible with the outcome of the lithofacies analysis. The paleochannels are very shallow in relation to their width, and have a planar, erosional bottom configuration, and in places a terrace bank morphology. The fluvial system features described here may indicate a terminal fan environment as the possible depositional location place of the Słupiec Formation sandy sediments. The source areas were located at the S and SE margins of the Intra-Sudetic Basin, and the flow was towards the W and NW towards its centre, to shallow inland basins, probably of a playa type. The red colour of the sediments may be indicative of arid or semi-arid climatic conditions in this environment during the Middle Rotliegendes .