scholarly journals Relationship between above-ground biomass allocation and stand density index in Populus x euramericana stands

2012 ◽  
Vol 85 (5) ◽  
pp. 611-619 ◽  
Author(s):  
L. Xue ◽  
D. F. Jacobs ◽  
S. Zeng ◽  
Z. Yang ◽  
S. Guo ◽  
...  
2016 ◽  
Vol 40 (5) ◽  
pp. 921-929 ◽  
Author(s):  
Ernani Lopes Possato ◽  
Natalino Calegario ◽  
Gilciano Saraiva Nogueira ◽  
Elliezer de Almeida Melo ◽  
Joyce de Almeida Alves

ABSTRACT The Reineke stand density index (SDI) was created on 1933 and remains as target of researches due to its importance on helping decision making regarding the management of population density. Part of such works is focused on the manner by which plots were selected and methods for the fit of Reineke model parameters in order to improve the definition of SDI value for the genetic material evaluated. The present study aimed to estimate the SDI value for Eucalyptus urophylla using the Reineke model fitted by the method of linear regression (LR) and stochastic frontier analysis (SFA). The database containing pairs of data number of stems per hectare (N) and mean quadratic diameter (Dq) was selected in three intensities, containing the 8, 30 and 43 plots of greatest density, and models were fitted by LR and SFA on each selected intensities. The intensity of data selection altered slightly the estimates of parameters and SDI when comparing the fits of each method. On the other hand, the adjust method influenced the mean estimated values of slope and SDI, which corresponded to -1.863 and 740 for LR and -1.582 and 810 for SFA.


2019 ◽  
Vol 65 (6) ◽  
pp. 776-783 ◽  
Author(s):  
Xiongqing Zhang ◽  
Quang V Cao ◽  
Lele Lu ◽  
Hanchen Wang ◽  
Aiguo Duan ◽  
...  

Abstract Stand density index (SDI) has played an important role in controlling stand stocking and modeling stand development in forest stands. Reineke’s SDI (SDI_R) is based on a constant slope of –1.605 for the self-thinning line. For Chinese fir plantations, however, it has been reported that the self-thinning slope varied with site and climate, rendering SDI_R questionable. Remeasured data from 48 plots distributed in Fujian, Jiangxi, Guangxi, and Sichuan provinces were used to develop models for prediction of stand survival and basal area, with SDI_R incorporated as a predictor variable. Also included in the evaluation were growth models based on self-thinning slopes estimated from two groups of sites (SDI_S) or from climate variables (SDI_C). Results indicated that models with climate-sensitive SDI (SDI_C) performed best, followed by SDI_S and SDI_R. The control models without SDI received the worst overall rank. Inclusion of climate-sensitive SDI in growth and survival models can therefore facilitate modeling of the relation between stand density and growth/survival under future climate-change conditions.


1989 ◽  
Vol 4 (4) ◽  
pp. 113-115 ◽  
Author(s):  
David E. Hibbs ◽  
Gary C. Carlton

Abstract Stocking guides based on Reineke's stand density index concept (diameter vs stem density) and on the self-thinning rule (volume vs stem density) are currently in use in the western United States. A self-thinning rule-based guide has been developed for red alder (Alnus rubra). In this paper, we develop a Reineke-type guide for red alder and compare the growth of thinned and self-thinning stands in both systems. Stand density appears to be defined differently in the two systems, leading to differences in density management prescriptions. West. J. Appl. For. 4(4):113-115, October 1989.


2005 ◽  
Vol 156 (12) ◽  
pp. 456-466 ◽  
Author(s):  
Hansheinrich Bachofen ◽  
Andreas Zingg

Stand structures and stand stability in unmanaged Norway spruce forests in the Swiss mountains may decline and their protective function against natural hazards will thus be put at risk. They are being subjected to thinning operations to improve stability and, in the long-term, to transform them into mountain selection forests. On pairs of research plots – thinned and not thinned – we will closely follow the stand development. Preliminary results indicate that the best variables to describe the effectiveness of the applied treatment to the stand structures are the h/d ratio,the spatial distribution and the stand density index.


2003 ◽  
Vol 18 (4) ◽  
pp. 259-266 ◽  
Author(s):  
Joel D. McMillin ◽  
Kurt K. Allen ◽  
Daniel F. Long ◽  
Jeri Lyn Harris ◽  
José F. Negrón

Abstract Western balsam bark beetle, Dryocoetes confusus (Coleoptera: Scolytidae), has caused widespread mortality of subalpine fir (Abies lasiocarpa) in western North America throughout the past decade. The objectives of this study were to document the effects of this mortality, relate mortality to pre-existing stand conditions, and investigate the role of storm-damaged fir in beetle population dynamics in north-central Wyoming. Transect cruise lines and pairs of infested and uninfested plots were installed to detect changes in the forest overstory and understory and to determine associations between stand conditions and beetle-caused fir mortality. On average, beetles killed more than 70 trees/ac over the last several years. This mortality resulted in significant decreases in: subalpine fir basal area, trees per acre, stand density index, and the percentage of subalpine fir stems in the overstory. Small, but significant increases were detected in the understory; herbaceous plant abundance increased in the infested plots compared with the noninfested plots. Moreover, significant positive linear relationships were found between the amount of fir mortality and the percentage of subalpine fir trees in a stand, subalpine fir basal area, and subalpine fir stand density index. In addition, a significant positive linear relationship was found between the percentage of wind-caused downed fir logs in an area and the percentage of logs utilized by western balsam bark beetle. The blowdown events that occurred in the mid-1990s in combination with a high percentage of fir component has provided ideal conditions for continued beetle expansion. West. J. Appl. For. 18(4):259–266.


1993 ◽  
Vol 17 (6) ◽  
pp. 773-779 ◽  
Author(s):  
Robert J. Lilieholm ◽  
Winifred B. Kessler ◽  
Karren Merrill

1990 ◽  
Vol 20 (12) ◽  
pp. 1909-1916 ◽  
Author(s):  
Brian V. Bredenkamp ◽  
Harold E. Burkhart

Data from three replications of a correlated curve trend experiment in Eucalyptusgrandis (Hill) Maiden were used to compare spacing indices developed by Reineke (stand density index), O'Connor (S-curve), Yoda (−3/2 power law), and Hart (relative spacing). The experiment tested 12 stand densities ranging from 25 to 6726 stems per hectare, and frequent repeat measurements to age 33 were available. Only data from treatments with stand densities greater than 124 stems per hectare and older than 10 years were included in the study to ensure all stands were approaching a limiting density. Relationships between the indices are developed, and it is shown that they are not independent of age. It is concluded that relative spacing is a useful measure of stand density as both site index and age are incorporated. A value of 0.05 for relative spacing is found as the limiting stand density for E. grandis.


2009 ◽  
Vol 24 (1) ◽  
pp. 5-10 ◽  
Author(s):  
Mark J. Ducey

Abstract The ratio between additive and original versions of Reineke's stand density index (SDI) has been used as a descriptor of stand structural complexity. That ratio also can be informative for designing efficient sampling methods and for the design of silvicultural experiments. Previous analyses of this ratio have assumed a diameter distribution without truncation, such that trees from zero to infinite dbh are possible. Truncation of the diameter distribution, e.g., by tallying only trees larger than some minimum dbh, moves the ratio much closer to one when the stand has a classic balanced uneven-aged structure. Minimum values of the ratio are found not with classic reverse-J distributions, but with sharply bimodal distributions that might be typical of a two-cohort stand. The implications for the use of novel sampling methods and for experimental designs to test whether the additive or original SDI provides better prediction in irregular stands are discussed.


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