Tree species composition and diversity along an altitudinal gradient in moist tropical montane valley slopes of the Garhwal Himalaya, India

Abstract:We identified and quantified regional and local environmental factors and spatial variation associated with tree-species composition across a 2000-m altitudinal gradient of Andean forest in north-western Argentina. A network of 47 1-ha plots was established along the altitudinal gradient within an area of about 25 000 km2; all trees ≥ 10 cm dbh were identified and measured. Constrained ordinations and variance-partitioning analyses were performed to investigate the determinants of tree-species distribution at the regional scale, across and within forest types (i.e. dry and cloud forests). We marked and measured a total of 22 240 trees belonging to 160 species. Significant environmental factors and spatial location combined accounted for 35% of total variation explained. A high proportion of variation was explained by climatic factors that were spatially structured; after removing the spatial effect, climate explained more variation in species composition across the complete gradient than did local factors. Relative importance of regional and local factors varied with geographic extent. Local factors explained more variation in tree-species composition at the within-forest scale than at the scale of the complete gradient. Our findings support the conceptual model of multi-scale controls on vegetation distribution, where local community composition and abundance result from processes at both regional and local scales.

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Langfristige Entwicklung von zwei Waldgesellschaften im Białowieża-Urwald

Schweizerische Zeitschrift fur Forstwesen ◽

10.3188/szf.2008.0080 ◽

2008 ◽

Vol 159 (4) ◽

pp. 80-90 ◽

Cited By ~ 3

Author(s):

Bogdan Brzeziecki ◽

Feliks Eugeniusz Bernadzki

Keyword(s):

Species Composition ◽

Tree Species ◽

Stand Structure ◽

Temporal Dynamics ◽

Structural Parameters ◽

Forest Communities ◽

Natural Forests ◽

Tree Species Composition ◽

Strong Trend ◽

Long Term Study

The results of a long-term study on the natural forest dynamics of two forest communities on one sample plot within the Białowieża National Park in Poland are presented. The two investigated forest communities consist of the Pino-Quercetum and the Tilio-Carpinetum type with the major tree species Pinus sylvestris, Picea abies, Betula sp., Quercus robur, Tilia cordata and Carpinus betulus. The results reveal strong temporal dynamics of both forest communities since 1936 in terms of tree species composition and of general stand structure. The four major tree species Scots pine, birch, English oak and Norway spruce, which were dominant until 1936, have gradually been replaced by lime and hornbeam. At the same time, the analysis of structural parameters indicates a strong trend towards a homogenization of the vertical stand structure. Possible causes for these dynamics may be changes in sylviculture, climate change and atmospheric deposition. Based on the altered tree species composition it can be concluded that a simple ≪copying≫ (mimicking) of the processes taking place in natural forests may not guarantee the conservation of the multifunctional character of the respective forests.

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Effects of nitrogen deposition on nitrate leaching from forests of the northeastern United States will change with tree species composition

Canadian Journal of Forest Research ◽

10.1139/cjfr-2016-0529 ◽

2017 ◽

Vol 47 (8) ◽

pp. 997-1009 ◽

Cited By ~ 5

Author(s):

Katherine F. Crowley ◽

Gary M. Lovett

Keyword(s):

United States ◽

Species Composition ◽

Nitrate Leaching ◽

Tree Species ◽

N Deposition ◽

Red Oak ◽

Northeastern United States ◽

Tree Species Composition ◽

White Ash ◽

Species Change

As tree species composition in forests of the northeastern United States changes due to invasive forest pests, climate change, or other stressors, the extent to which forests will retain or release N from atmospheric deposition remains uncertain. We used a species-specific, dynamic forest ecosystem model (Spe-CN) to investigate how nitrate (NO3–) leaching may vary among stands dominated by different species, receiving varied atmospheric N inputs, or undergoing species change due to an invasive forest pest (emerald ash borer; EAB). In model simulations, NO3– leaching varied widely among stands dominated by 12 northeastern North American tree species. Nitrate leaching increased with N deposition or forest age, generally with greater magnitude for deciduous (except red oak) than coniferous species. Species with lowest baseline leaching rates (e.g., red spruce, eastern hemlock, red oak) showed threshold responses to N deposition. EAB effects on leaching depended on the species replacing white ash: after 100 years, predicted leaching increased 73% if sugar maple replaced ash but decreased 55% if red oak replaced ash. This analysis suggests that the effects of tree species change on NO3– leaching over time may be large and variable and should be incorporated into predictions of effects of N deposition on leaching from forested landscapes.

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