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Investigation of tree characteristics for traffic noise abatement

Sultan Tamoor, Shahid Saman, Rasheed Jawad, Alsubai Shtwai

Environment Protection Engineering

2024

Vol. 50, nr 1

43--70

There is a connection between noise reduction and roadside tree plantation. Understanding how properties of trees (density, height, leaf type, crown spread, etc.) impact noise attenuation is crucial. The current study measured and compared the roadside traffic noise at various locations (with/without trees/plantations) in selected Multan areas. Eight locations (Bahawalpur Road, Expressway, Vehari Road, Bosan Road, Eidgah Road, Masoom Shah Road, Piran-Gaib Road, and Khanewal Road) throughout Multan City. A digital sound level meter (MS-6701) was used to measure the noise levels during months of winter and summer seasons. During field visits, the tree type, leaf type, average height, density, canopy crown spread, and presence of any vegetation in each designated area were noted. The sound pressure data was compared with the noise level standards as recommended by Punjab Environment Quality Standards. A clear reduction in sound levels can be observed with trees. The tree plantings reduced the noise only on the Expressway (65 dbA) and Piran Gaib Road (64 dbA) in May 2022. In June 2022, the trees were only beneficial in reducing noise near Piran Gaib Road (64 dbA). Due to tree plantation, the maximum reduction of 11 dbA) was reported in June 2022 at Eig Gah Road, followed by a 10.1 dbA) reduction in December 2021 at Khanewal Road. Maximum noise reduction was observed at the Expressway and Piran Gaib Roads, where Pongamia pinata and Melia azedarach are planted along with some grass. The comparison clearly showed a reduction in noise due to roadside plantations. Tree plantation helps improve the area's overall look and enhances aesthetic sense and scenic beauty.

Structure of Dominance among Tree Species in Relic Swiss Stone Pine (Pinus cembra L.) Forests in Tatra Mountains

Zięba Antoni, Różański Wojciech, Szwagrzyk Jerzy

Polish Journal of Ecology

2020

Vol. 68, nr 2

159--171

Pinus cembra forests are limited to the Alps and Carpathians. Although several studies regarding their structure were carried out in some locations in the Tatra Mts. it required further investigations. Therefore, the aims of this study were to describe the stand and shrub structure of P. cembra forests, compare their structure with the Picea abies forests and analyse differences between silicate and calcicolous P. cembra forests in the Tatra Mts. The data were collected on the 16 sampling plots (500 m2), in the Swiss stone pine and Norway spruce forests. We measured the diameter at breast height (dbh) of each tree and recorded the young trees and shrubs. In order to compare species composition between silicate and calcicolous P. cembra forests, we made 91 relevés in their entire range of distribution (917 ha). Furthermore, we examined the share of main tree species along the altitude and inclination gradients, using the GAM models. The tree density in the P. cembra forests reaches 618 stems per ha, whereas their basal area (BA) 23.17 m2 ha-1. Main tree species are P. cembra and P. abies. P. cembra dominates in the higher thickness classes. The BA and dbh structure varies significantly between P. cembra and P. abies forests. The most abundant juveniles are P. abies and Sorbus aucuparia. The differences between forests growing on different substrate are relatively low. The altitude has a significant impact on the share of P. cembra (increase) and P. abies (decrease). The inclination has a significant impact on the increase of share of P. cembra.

Determining the number of trees using airborne laser scanning and true orthoimagery

Tompalski P., Wężyk P., de Kok R., Kukawski M.

Roczniki Geomatyki

2009

T. 7, z. 2

133-141

A multi-level forestry model, which is not only to predict income, requires accurate and rapid information about its resources. Precisely determined parameters such as diameter at breast height (dbh), height, canopy closure and volume are essential for proper decision making and therefore for forest management. Typical methods of tree/forest measurement in Poland are based on statistical methods and define average stand parameters from surveys done on selected areas (grid of forest inventory plots). It has been shown by many authors that CIR images and airborne laser scanning (ALS) data are suitable for determining selected forest parameters (Dubayah, Drake 2000; Lefsky et al., 2002). The main issue with airborne laser scanning, for forests concerns the vertical structure (Hyyppä et al., 2006; Wężyk et al., 2008). Airborne images (photos or line scanner multi- or hyperspectral imagery), on the other hand, can deliver information about tree species and health conditions by means of interpretation and classification (Wężyk et al., 2003; Lillesand et al., 2007). Both types of data can be used for determining tree numbers, tree density and spatial arrangement (Brandtberg, Walter, 1998; Leckie et al., 2003; Wang et al., 2004; Koch et al., 2006). The number of trees in the forest unit changes over the time. The older the forest stand is, the fewer tree stems it has, and even if planted in a regular order, different habitat conditions and competition between them, lead to diversified spatial distribution of trees in the stand. The purpose of this study was to test the different approaches of determining the number of trees using ALS and true orthoimagery datasets and compare the results to a reference. The study transect was located in the central-west Poland, in the Milicz Forest District RDLP Wrocław (WGS84: 51°27' N; 17°12' E), covering approximately 3.2 ha. The area was selected from a homogeneous part of a subcompartment (236a) covered by Scots Pine forest (Pinus sylvestris L.). The age of the stand, according to Polish State Forest database (SILP/LAS), was 107 years, the mean height was 23 m and the dbh was 30 cm.

Stosowany obecnie model leśnictwa wielofunkcyjnego wymaga aktualnej i dokładnej informacji o jego zasobach. Jednym z wielu ważnych parametrów drzewostanu jest liczba drzew i ich przestrzenne rozmieszczenie. Obie te cechy zmieniają się w czasie życia drzewostanu. Im starszy jest drzewostan tym mniej drzew posiada. Pomimo faktu, że drzewa sadzone są z reguły w regularnej więźbie, zróżnicowanie warunków siedliskowych oraz konkurencja pomiędzy drzewami prowadzi do niejednakowego przestrzennego rozmieszczenia drzew oraz zróżnicowania ich rozmiaru. Celem badań było okre ślenie liczby drzew w drzewostanie sosnowym (Pinus silvestris L.) na podstawie danych z lotniczego skaningu laserowego (ALS) oraz obrazu pozyskanego za pomocą skanera linijkowego (true ortho RGB/NIR). Analizy zostały przeprowadzone w wybranym transekcie 107 letniego drzewostanu na terenie nadleśnictwa Milicz. Jako danych referencyjnych użyto liczby drzew określonej na podstawie zwektoryzowanych koron. Dwie różne metody zostały zastosowane do automatycznego określenia liczby drzew i ich położenia. Pierwsza metoda, nazwana "GIS watershed" oparta była na modelach koron generowanych z danych ALS. Zastosowano różne algorytmy w celu znalezienia optymalnego modelu jak najdokładniej reprezentującego powierzchnię koron drzew. Druga metoda nazwana OBIA oparta była o segmentację oraz klasyfikację obrazu true ortho (R, G, B, NIR) i prowadziła do wykrycia tzw. hot-spot. Zastosowano również metodę łączącą dane lidarowe oraz true ortho (data fusion). Do porównania uzyskanych wyników zastosowano analizy przestrzenne. Wyniki wskazują że zarówno dane ALS jak i dane obrazowe mogą być użyte do określania liczby drzew w rębnym drzewostanie sosnowym. Dokładność wykrycia drzew wyniosła 67% dla metody pierwszej (ALS) oraz 74.5% dla metody drugiej (true ortho). Połączenie zestawów danych zaowocowało wynikiem równym 72.6%. Badania będą kontynuowane w celu poprawy rezultatów dla zastosowanych metod, również dla drzewostanów w innym wieku i o innym składzie gatunkowym.