Various authors have identified distinct components in the diel cycle of stem size. Herzog et al. [22] divided daily fluctuations of Norway more info spruce stems into five phases, representing rates of change and hydration states of the phloem and xylem within the general framework of nocturnal recharge and daily dehydration. They also suggested that there may be several separate reservoirs of water within the tree that get depleted on various timescales, some diurnal and some longer. This topic has been further investigated through modeling of water flow and stem storage dynamics [23,24]. Dendrometers have been used under both controlled conditions [23,25,26] and in field observational studies [22,27�C30] to separate wood radial growth from transient changes caused by water balance components.

The diel stem size cycle is now commonly divided in three distinct phases: a contraction, usually associated with Inhibitors,Modulators,Libraries stem desiccation during the day, followed by an expansion, normally in the evening, and a true stem radius increase. This approach was proposed by Downes et al. [28] as a simplification of the five-phase approach. The irreversible portion of the diurnal change Inhibitors,Modulators,Libraries is the Stem Radial Increment (SRI), which is calculated by comparing the Inhibitors,Modulators,Libraries daily maximum of stem size to the previous daily maximum, and is assumed to be zero when the current-day maximum does not reach the previous-day maximum. In order to investigate environmental controls on radial growth of tropical treeline trees, we conducted a multi-year observational field study to quantify the relationship between SRI of Pinus hartwegii Lindl.

and several hydroclimatic variables controlled by the North American Monsoon System [31,32]. Our main objective was to test the relationship between average ring-width indices at the site and June precipitation in Colima, Mexico, that had been identified in a previous study [11], given that ecological studies provide the necessary information to properly interpret proxy records, Inhibitors,Modulators,Libraries such as those derived from tree rings, used in paleoclimatic reconstructions.2.?Experimental Entinostat SectionThe study site is located on Nevado de Colima, Mexico (Figure 1), in pure, uneven-aged stands of Mexican mountain pine (Pinus hartwegii Lindl), the dominant treeline species in tropical North America [33,34]. Nevado is at the western end of the trans-Mexican volcanic belt, which includes several of the tallest mountains in central America [35].

The climate of the study area is typical of the North American Monsoon System [36], with a distinct summer wet season (June�COctober) and a prolonged dry season (November�CMay). The dry season is accompanied by cold fronts, occasionally producing limited snow fall at the highest elevations [37].Figure 1.Global selleck and topographic maps showing the location of the study area on Nevado de Colima (NDC), Mexico, in relation to the nearby Volc��n de Fuego (VDF). Contour lines are drawn at 100 m intervals; the automated weather station () and two …