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Edge Effects on Tree Growth and Species Diversity in Forests of Different Types and Ages

Li J., Zhao C., Peng Y., Hu Y., Yuan X.

Polish Journal of Ecology

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2018

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Vol. 66, nr 3

239--249

EN

Edge to interior gradients in forest ecosystems can influence the species composition and community structure as a result of variations in micro-environment. In this study, the edge effects on stand productivity and plant species diversity were investigated in two adjacent types of forests in central-southern China: Chinese fir adjacent with pine forests and Chinese fir adjacent with broad-leaved forests. A total of 48 sample plots for overstory and 240 sample quadrates for understory in different stand ages were set up. The tree growth parameters were measured in the overstory while the plant species diversity was measured in both overstory and understory of the examined forests. The results showed that DBH (tree diameter at the breast height), tree height and stand volume in overstory increased from the central areas (CA) of forests to the edge areas (EA), and the plant species richness and diversity in understory were greater in EA than in CA. The edge effect was greater in Chinese fir paired with broad-leaved forests than in Chinese fir paired with pine forests. The edge effect decreased in an order as young aged stands > middle aged stands > mature aged stands in the studied forests. The changes in tree growth and species diversity in the edge area compared to the interior were mainly attributed to the alteration of micro-environmental factors such as light density, temperature and moisture. Our results suggest increasing forest productivity and plant species diversity could be achieved by making more edges in the forests.

2

Climatic signal in tree-ring chronologies of Cedrus deodara from Chitral Hindukush range of Pakistan

Khan N., Ahmed M., Shaukat S. S.

Geochronometria

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2013

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Vol. 40, no. 3

195--207

EN

Tree-rings are an important tool for the investigation of paleoclimatic records for regions or periods of time with no instrumental climatic data. However, the responses of different species and sites to various climatic parameters are unusual. In the present study, we developed tree-ring-width chronologies of Cedrus deodara from three different sites of Chitral Hindukush range of Pakistan. The study was conducted to understand tree-growth climate relationship and its applicability in proxy climate investigations. The chronologies covered the past 469 to 595 years, with a mean segment length (MSL) ranging from 148 to 223 years. Climatic data obtained from the three weather stations showed strong correlation and was found useful for tree-ring climate relationships. Correlation Function (CF) and Response Function (RF) analysis showed that spring precipitation (March-May) is a critical limiting factor for tree-ring growth, and temperature prior to November may also play a major role in affecting tree ring-growth. The results exposed that the three sites have con-tinuous relationship indicated that only single species from different locations are affected by the same environmental variables and hence can be used in climate reconstruction in combination. The Cedrus deodara chronologies developed at different locations had several corresponding narrow and wide marker rings indicating a large macroclimatic response to regional climatic conditions. The cur-rent study suggests that the tree-rings of Cedrus deodara from the Chitral Hindukush range could be used to develop chronologies for the reconstruction of seasonal climatic variables.

3

Growth and nutrition of restored Quercus castaneifolia C.A. Mey. versus native Celtis australis L. tree species : conservation perspectives of Hyrcanian forest (Iran)

Hosseini S., Raouhi-Moghaddam E., Ebrahimi E., Rahmani A., Tabari M.

Polish Journal of Ecology

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2010

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Vol. 58, nr 1

41-51

EN

For native species, mixed plantation systems seem to be the most appropriate for providing a broader range of options such as production, protection, biodiversity conservation and restoration. After 11 years, growth and nutrition and soil properties were examined in young plantation of two indigenous tree species in Hyrcanian forests of Iran. Quercus castaneifolia C.A. Mey. (as target species) and Celtis australis L. (as native component species) were planted in five proportions (100Q, 70Q:30C, 60Q:40C, 50Q:50C, 40Q:60C) in Noor, Iran. Diameter at breast height of individual Quercus trees and total basal area were affected by the presence of Celtis. Percent retranslocation of nutrients in Quercus followed in order: K> P> N. Leaf-litter fall production ranged from 4.10 to 6.14 t ha[^-1] year[^-1]. Ca and Mg concentrations in fully expanded leaves of Quercus, N and K retranslocation of Quercus, concentration of available P in soil were higher in some of the mixed plantations than in monoculture of Quercus. On the other hand, N concentration in fully expanded leaves of Quercus, N fluxes and soil C/N ratio were higher in monoculture of Quercus. Within the framework of this experiment, it appeared that production was maximized when these two species were grown together in the proportion of 60% Quercus and 40% Celtis.

4

Drzewa i krzewy do miast. [Cz. 1]

Bojarczuk T., Rachwał L.

Zieleń Miejska

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2006

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Nr 2

14-15

PL

Warunki wzrostu drzew i krzewów w miastach, a zwłaszcza na terenach towarzyszących arteriom komunikacyjnym, są bardzo trudne. Dlatego bardzo ważny jest ich własciwy dobór i pielęgnacja.

5

Effect of the pest Marchalina hellenica Gennadius (Homoptera, Margarodidae) on the growth parameters of Pinus brutia Ten. in Muğla Region (Turkey)

Yeşil A., Gürkan B., Saraçoğlu Ö., Zengin H.

Polish Journal of Ecology

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2005

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Vol. 53, nr 3

451-458

EN

Marchalina hellenica Gennadius is a common pest prevalent in Pinus brutia Ten. forests in Muğla province of Mediterranean Region of Turkey (28°20'03'' E; 37°12'18'' N). The pest is known to suck sap from a number of pine tree species, especially Pinus brutia. The goal of this research is to determine whether the pest has a negative effect on the volume increments of Pinus brutia trees and forests. Two areas with identical site conditions are selected for study: one non-infested and one infested with Marchalina hellenica. The effects of site quality and age on the sampled trees have been eliminated. The diameter growth at breast height, basal area (the cross-sectional area of a tree at breast height) and the increment of tree volume are determined separately for both study areas. A t-test applied to volume increments of both infested and non-infested trees of all ages proves that infestation causes significant negative impacts on trees between the ages of 40 and 80 years. The greatest loss of increment in single trees is 2.0% (of the volume of non-infested tree) which occurs at the age of 70 years old. When considering the entire stand, the greatest loss of increment is 3.4% (of the volume of non-infested stand) which occurs at the age of approximately 45 years.