Analyses of growth rings of Pinus merkusii from Lao P.D.R.

Abstract

We present the first tree-ring chronologies of total ring width (RW), earlywood width (EWW) and latewood width (LWW) from Lao P.D.R., from 52 core samples from 26 mature pines (Pinus merkusii Junghuhn & De Vriese), from Phu Khao Khouay National Biodiversity Conservation Area northeast of Vientiane. The chronologies span the 262-year period from 1743 to 2005 A.D., and at least for RW and LWW exhibit strong signal strength back to the late 1700s. Correlation analyses with climate data from a composite of 13 nearby stations in Thailand indicate statistically significant ( p 0.05) negative correlation with prior year June rainfall, and positive correlation with August-September maximum temperature. Annual radial increment is also significantly negatively correlated with percent cloud fraction, leading us to believe that growth may be adversely affected by light availability (i.e., reduced growth during periods of low light) and not positively affected by high temperature per se. Spatial correlation with sea surface temperature fields highlights the influence of the central and eastern tropical Pacific Ocean, particularly for EWW. Wavelet analysis reveals multi-decadal scale variability between 30 and 60 years for all three indices, and higher frequency power for RW and LWW between 2 and 7 years, the typical range of ENSO. While RW, EWW and LWW all appear to respond to monsoon climate, we highlight the need for far more detailed ecophysiological response studies for this species, particularly with regard to the role of light availability and temperature during the peak monsoon. #

Dendroecology in the tropics: a review

“…Also negative correlations between growth and rainfall have been reported (e.g. Buckley et al 2007;Soliz-Gamboa et al 2010), which may indicate a response to higher light levels due to low cloud cover. Most studies report correlations between growth and rainfall, as temperature shows in general little interannual variation in tropical areas.…”

“…For some species, nevertheless, a correlation was found between both growth and temperature and growth and precipitation (e.g. Trouet et al 2001;Buckley et al 2007;López and Villalba 2010). In Amazonian floodplain forests tree growth was found to be correlated with the water level in the non-flooded period (Dezzeo et al 2003), or with the length of the non-flooded phase (Schöngart et al 2005).…”

Ages and long-term growth patterns of four threatened Vietnamese tree species

“…Next, we checked for gradual changes in diameter growth over time, and compared diameter growth rates obtained from ring analysis with values from permanent sample plots (Chien et al 2008). To our knowledge, this is one of the first dendro-ecological studies for tropical Asian species (Baker et al 2005;Buckley et al 2007) and the first of its kind on threatened tree species.…”

“…Tree ring analysis can assist in obtaining such basic information, as it allows the lifetime reconstruction of growth rates of individual trees (Roig et al 2005;Newton 2007;Soliz-Gamboa et al 2010). Tree ring data obtained from increment cores can be obtained without harming trees, and is therefore particularly suitable for the study of threatened tree species (e.g., Buckley et al 2007). …”

DENDROCRONOLOGIA DE ÁRVORES DE Schizolobium parahyba(Vell.) S. F. Blake DE OCORRÊNCIA NA REBIO DE TINGUÁ-RJ

“…Ocorrem correlações com a precipitação total anual, no período das chuvas, na estação seca, no período de transição e no ano prévio ZUIDEMA, 2011). Alguns estudos evidenciam correlação negativa entre crescimento e precipitação (BUCKLEY et al, 2007;SOLIZ-GAMBOA et al, 2010), o que demonstra diferentes estratégias de crescimento em relação a uma mesma variável climática. Na floresta Atlântica, pesquisas que versam sobre a ocorrência e periodicidade da formação de anéis de crescimento abrangem diferentes tipologias do bioma, como: Floresta Ombrófila Densa (CALLADO et al, 2001a), Floresta Estacional Semidecidual (TOMAZELLO-FILHO et al, 2004, Floresta Estacional Decidual e Floresta Ombrófila Mista (OLIVEIRA, 2007).…”