scholarly journals Functional identity regulates aboveground biomass better than trait diversity along abiotic conditions in global forest metacommunities

Ecography ◽  
2021 ◽  
Author(s):  
Li‐Qiu Wang ◽  
Arshad Ali
Keyword(s):  
Aboveground Biomass ◽  
Functional Identity ◽  
Abiotic Conditions ◽  
Trait Diversity ◽  
Better Than

scholarly journals Individual-level trait diversity predicts phytoplankton community properties better than species richness or evenness

2017 ◽  
Vol 12 (2) ◽  
pp. 356-366 ◽  
Author(s):  
Simone Fontana ◽  
Mridul Kanianthara Thomas ◽  
Mirela Moldoveanu ◽  
Piet Spaak ◽  
Francesco Pomati
Keyword(s):  
Species Richness ◽  
Phytoplankton Community ◽  
Individual Level ◽  
Trait Diversity ◽  
Better Than

Pyrus calleryana (Callery pear) allometric equations and stand structure in southwestern Ohio and northern Kentucky

2020 ◽  
pp. 1-29
Author(s):  
Richard L. Boyce ◽  
Miciah Ocasio
Keyword(s):  
Aboveground Biomass ◽  
Stand Density ◽  
Allometric Equations ◽  
Native Forest ◽  
Pyrus Calleryana ◽  
Density Indices ◽  
Biomass Components ◽  
Callery Pear ◽  
Better Than ◽  
Diameter Distributions

Abstract Pyrus calleryana Decne. (Callery pear), a native of eastern Asia, has recently emerged as an important woody invader in much of the eastern U.S. Little is known about its ecology in its new range. Its shade tolerance may be an important indicator of areas it is likely to invade. In this study, allometric equations were first developed to predict aboveground biomass components, including wood, branches, bark, leaves, and fruit, from diameter at stump height (dsh; 25 cm), by destructively harvesting 13 trees, ranging from 0.1 to 19.3 cm dsh. Then, a total of 23 wild-grown stands in the northern Kentucky/southwestern Ohio region were surveyed, with diameters of all woody stems sampled. Pyrus calleryana density, basal area, aboveground biomass, stand density index, size distribution inequality, and importance value were calculated for each site. Two-factor Weibull distributions were fit to diameter distributions. Allometric equations provided good fits for total aboveground biomass as well as individual components. Aboveground biomass levels fell below mean levels of native forest stands found in the US. Stand density indices yielded values typical of shade-intolerant or midtolerant species. Stands with smaller trees generally had steeply declining monotonic diameter distributions, while stands with larger, trees trended toward positively-skewed monotonic distributions. These findings are consistent with a species that is either shade-intolerant or midtolerant. Thus, while this species is expected to invade open or disturbed areas, it is not expected to be an important invader under forest canopies. However, its extended deciduous habit is one shared by other understory woody invaders, and so this may allow it to survive under forest canopies. Management Implications Callery pear, which has been used in landscape plantings for decades, is now being recognized as important woody invader in much of the eastern U.S. However, little is known now about its impact on native forest stands. Here, we developed allometric equations to predict aboveground biomass components, including wood, branches, bark, leaves, and fruit, as well as total aboveground biomass, from diameter at stump height (dsh; 25 cm) measurements; dsh often works better than dbh (diameter at breast height; 1.37 m) with this species because pear stems often fork below breast height. However, there is a strong relationship between dsh and dbh, so these allometric equations can used with dbh measurements. Most biomass equations were log-log regressions, and they were corrected for bias using the UMVU estimator. However, this estimator does not give a ready-to-use equation; the original data must be used along with collected data in an R routine. Thus, we also report equations corrected with the smearing estimate, which, while not as good as the UMVU estimator, performs better than most commonly used estimators. The allometric equations will allow managers to estimate biomass of stands dominated by Callery pear. Diameter distributions from 23 wild-grown stands in the northern Kentucky/southwestern Ohio region were fit to two-factor Weibull distributions, which indicated a species that is either shade-intolerant or midtolerant, which was also indicated by relatively low stand density indices. For managers, this suggests that control efforts for Callery pear should focus on disturbed or open areas, as our results suggest that it will not become an important invader in closed-canopy forests.

scholarly journals EDITOR'S CHOICE: REVIEW: Trait matching of flower visitors and crops predicts fruit set better than trait diversity

2015 ◽  
Vol 52 (6) ◽  
pp. 1436-1444 ◽  
Author(s):  
Lucas A. Garibaldi ◽  
Ignasi Bartomeus ◽  
Riccardo Bommarco ◽  
Alexandra M. Klein ◽  
Saul A. Cunningham ◽  
...  
Keyword(s):  
Fruit Set ◽  
Flower Visitors ◽  
Trait Diversity ◽  
Better Than

The Effect of Stand Age and Climate on Aboveground Biomass Accumulation of Pinus tabulaeformis Forests

2013 ◽  
Vol 726-731 ◽  
pp. 4266-4269
Author(s):  
Fei Li ◽  
Hua Yong Zhang ◽  
Zhong Yu Wang ◽  
Yang Su ◽  
Lu Han
Keyword(s):  
Aboveground Biomass ◽  
Predictive Power ◽  
Explanatory Power ◽  
Biomass Accumulation ◽  
Pinus Tabulaeformis ◽  
Stepwise Multiple Regression ◽  
Stand Age ◽  
Mean Annual Precipitation ◽  
Mean Annual Temperature ◽  
Better Than

In order to investigate the effect of stand age and climate hydrothermic factors on aboveground biomass accumulation (ABA), data from 65 typical Pinus tabulaeformis forest stands were compiled from published literatures. By means of stepwise multiple regression, the variations in ABA were examined across the range of stand age and gradients of mean annual precipitation (MAP) and mean annual temperature (MAT). For comparison, stand age was also used as explaining variable alone. The results show that, stand age and MAP could explain 85.1% of variation in ABA, the predictive power is much better than stand age alone. The explanatory power of stand age and MAP were 70.7% and 15.3% respectively. In comparison with stand age, MAP has a relatively poor but significant effect. ABA is not significantly related to MAT, which implies that water availability is more important than thermal condition for ABA of Pinus tabulaeformis forests.

Time and Latitude in South Africa

1972 ◽  
Vol 1 ◽  
pp. 27-38
Author(s):  
J. Hers
Keyword(s):  
South Africa ◽  
Cape Town ◽  
Astronomical Observations ◽  
Royal Observatory ◽  
The Republic ◽  
Astronomical Determination ◽  
Limited Accuracy ◽  
Better Than

In South Africa the modern outlook towards time may be said to have started in 1948. Both the two major observatories, The Royal Observatory in Cape Town and the Union Observatory (now known as the Republic Observatory) in Johannesburg had, of course, been involved in the astronomical determination of time almost from their inception, and the Johannesburg Observatory has been responsible for the official time of South Africa since 1908. However the pendulum clocks then in use could not be relied on to provide an accuracy better than about 1/10 second, which was of the same order as that of the astronomical observations. It is doubtful if much use was made of even this limited accuracy outside the two observatories, and although there may – occasionally have been a demand for more accurate time, it was certainly not voiced.

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