Grazing Effects on the Easily Measurable Plant Functional Traits of <I>Quercus semecarpifolia</I> Sm. Seedlings

Tshewang Dorji; Dorji Gyaltshen; Damber Kr. Ghemiray; Pema Wangda; Kenji Fukuda

doi:10.36808/if/2015/v141i3/63868

Grazing Effects on the Easily Measurable Plant Functional Traits of Quercus semecarpifolia Sm. Seedlings

Authors

Tshewang Dorji RNR RDC Yusipang, Thimphu
Dorji Gyaltshen RNR RDC Yusipang, Thimphu
Damber Kr. Ghemiray RNR RDC Yusipang, Thimphu
Pema Wangda RNR RDC Yusipang, Thimphu
Kenji Fukuda Institute of Environmental Sciences, The University of Tokyo

DOI:

https://doi.org/10.36808/if/2015/v141i3/63868

Keywords:

Brown Oak, Functional Traits, Seedlings, Leaf Mass per Area, Leaf Nitrogen Content, Forest Grazing.

Abstract

In a temperate broadleaf forest of Western Bhutan dominated by old growth brown oak (Quercus semicarpifolia sm.) with a history of overgrazing, we aimed to study the grazing response of oak seedlings by comparing grazed and ungrazed seedlings based on some easily measurable plant functional traits such as plant height, leaf area and leaf mass area ratios (LMA).

Our study found that grazing was strongly associated with shorter plant height, thicker leaves, smaller leaf area and high leaf mass per area ratios (LMA) of Quercus semecarpifolia seedlings. Seedling collar diameter increment was not affected by grazing. LMA was found to be the best plant trait that could optimally predict the grazing response on plant growth. Shorter plant height, higher LMA and leaf thickness coupled with presence of more surface spines in the leaves of grazed plants could be some forms of grazing resistance or herbivory tolerance rather than adaptations to survive repeated herbivory. The study concludes that higher LMA values do not necessarily be limited to plants of nutrient poor sites or those growing under climatic stresses as generally assumed but are also attributed by anthropogenic activities like overgrazing.

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