Relationships between loblolly pine yield and woody plant diversity in Virginia Piedmont plantations

1999 ◽  
Vol 29 (7) ◽  
pp. 1065-1072 ◽  
Author(s):  
Lisa E Schabenberger ◽  
Shepard M Zedaker
Keyword(s):  
Species Richness ◽  
Loblolly Pine ◽  
Plant Diversity ◽  
Woody Plant ◽  
Basal Area ◽  
Plant Species Richness ◽  
Shannon Index ◽  
Vegetation Control ◽  
Virginia Piedmont ◽  
Competition Control

This study was established to determine the effects of competition control on loblolly pine (Pinus taeda L.) yield and woody plant diversity in Virginia Piedmont plantations 12-14 years of age. In a factorial experiment, loblolly pine and competing woody vegetation were analyzed at eight levels of competition control: total, two-thirds, one-third, or no woody stem control in combination with either total or no herbaceous vegetation control. Pine yield increased linearly with increasing levels of woody control intensity. As woody control increased, noncrop woody plant basal area and woody plant diversity (Shannon index (H')) in the canopy decreased. Woody plant species richness in the canopy was reduced by herbaceous control and by total woody control. Percent woody cover, H', and species richness in the understory were not affected at any level of competition control. Regression analysis was used to examine relationships between loblolly pine yield, noncrop woody dominance and canopy plant diversity (H'). Pine yield was negatively correlated (R2 = 0.74) with the percentage of noncrop woody basal area (PNCW BA) in the canopy, while canopy diversity was proportional to PNCW BA (R2 = 0.97). Canopy diversity was inversely related to pine yield (R2 = 0.77), with a high trade-off in diversity at low yield levels, but with decreasing sensitivity as pine yield increased.

scholarly journals A Dynamic Stand Growth Model System for Loblolly Pine Responding to Mid-Rotation Treatments

Forests ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 556
Author(s):  
Mauricio Zapata-Cuartas ◽  
Bronson P. Bullock ◽  
Cristian R. Montes ◽  
Michael B. Kane
Keyword(s):  
Growth Model ◽  
Loblolly Pine ◽  
Basal Area ◽  
Model System ◽  
Growth And Yield ◽  
Site Quality ◽  
Response To Treatment ◽  
Plantation Management ◽  
Vegetation Control ◽  
Dominant Height

Intensive loblolly pine (Pinus taeda L.) plantation management in the southeastern United States includes mid-rotation silvicultural practices (MRSP) like thinning, fertilization, competitive vegetation control, and their combinations. Consistent and well-designed long-term studies considering interactions of MRSP are required to produce accurate projections and evaluate management decisions. Here we use longitudinal data from the regional Mid-Rotation Treatment study established by the Plantation Management Research Cooperative (PMRC) at the University of Georgia across the southeast U.S. to fit and validate a new dynamic model system rooted in theoretical and biological principles. A Weibull pdf was used as a modifier function coupled with the basal area growth model. The growth model system and error projection functions were estimated simultaneously. The new formulation results in a compatible and consistent growth and yield system and provides temporal responses to treatment. The results indicated that the model projections reproduce the observed behavior of stand characteristics. The model has high predictive accuracy (the cross-validation variance explained was 96.2%, 99.7%, and 98.6%; and the prediction root mean square distance was 0.704 m, 19.1 trees ha−1, and 1.03 m2ha−1 for dominant height (DH), trees per hectare (N), and basal area (BA), respectively), and can be used to project the current stand attributes following combinations of MRSP and with different thinning intensities. Simulations across southern physiographic regions allow us to conclude that the most overall ranking of MRSP after thinning is fertilization + competitive vegetation control (Fert + CVC) > fertilization only (Fert) > competitive vegetation control only (CVC), and Fert + CVC show less than additive effect. Because of the model structure, the response to treatment changes with location, age of application, and dominant height growth as indicators of site quality. Therefore, the proposed model adequately represents regional growth conditions.

scholarly journals Superhost Plants Alter the Structure of Plant–Galling Insect Networks in Neotropical Savannas

Plants ◽  
2019 ◽  
Vol 8 (10) ◽  
pp. 369 ◽  
Author(s):  
Araújo ◽  
Moreira ◽  
Falcão ◽  
Borges ◽  
Fagundes ◽  
...  
Keyword(s):  
Species Richness ◽  
Plant Species ◽  
Plant Diversity ◽  
Host Plants ◽  
Plant Species Richness ◽  
Variable Number ◽  
Insect Species ◽  
Species Number ◽  
Neotropical Savannas ◽  
Galling Insects

Host plants may harbor a variable number of galling insect species, with some species being able to harbor a high diversity of these insects, being therefore called superhost plants. In the present study, we tested the hypothesis that the occurrence of superhost plant species of genus Qualea (Vochysiaceae) affects the structure of plant–galling insect ecological networks in Brazilian Cerrado. We sampled a total of 1882 plants grouped in 131 species and 43 families, of which 64 species and 31 families of host plants hosted 112 galling insect species. Our results showed that occurrence of superhosts of genus Qualea increased the linkage density of plant species, number of observed interactions, and the size of plant–galling insect networks and negatively affected the network connectance (but had no effect on the residual connectance). Although the occurrence of Qualea species did not affect the plant species richness, these superhosts increased the species richness and the number of interactions of galling insects. Our study represents a step forward in relation to previous studies that investigated the effects of plant diversity on the plant–insect networks, showing that few superhost plant species alter the structure of plant–herbivore networks, even without having a significant effect on plant diversity.

Termite diversity and abundance across fire-induced habitat variability in a tropical moist savanna (Lamto, Central Côte d'Ivoire)

2010 ◽  
Vol 26 (3) ◽  
pp. 323-334 ◽  
Author(s):  
Kanvaly Dosso ◽  
Souleymane Konaté ◽  
Daouda Aidara ◽  
K. E. Linsenmair
Keyword(s):  
Species Richness ◽  
Environmental Variables ◽  
Fire History ◽  
Woody Plant ◽  
Plant Species Richness ◽  
Gallery Forest ◽  
Habitat Variability ◽  
Savanna Woodland ◽  
Species Abundances ◽  
Forest Island

Abstract:At Lamto, little is known about animal community responses to habitat variability resulting from fires and the mosaic pattern of the vegetation in general and in particular about that of termites which play key roles in this ecosystem. With a standardized method, data were collected on termites from four habitats differing in their vegetation cover and fire-history: annually burned savanna, savanna woodland, forest island and gallery forest. A range of environmental variables was measured and correlated with species abundances. The number of termite species collected in the savanna woodland was very close to that found in the gallery forest while the forest island was the richest habitat. The species richness of the savanna woodland and forest island seemed partly due to their heterogeneous and transitional vegetation structures and variable food resources. With regard to the fire-history of habitats, Connell's intermediate disturbance hypothesis offers an explanation for differences in the patterns of habitat-specific species richness. Variation in species abundances was significantly correlated with only two environmental variables (soil pH and woody plant species richness). The pH appeared as the most influential factor for fungus-growers while tree invasion in the savanna strongly reduces the abundance of grass-feeding species (e.g. Trinervitermes geminatus). Although not significantly correlated with species abundances, soil carbon showed a positive correlation with the dominant soil-feeder Basidentitermes potens. As for wood-feeders, they were not strongly correlated with woody plant species richness; this fact might be linked to their use for other sources of nourishment. Overall, it appears that habitat variability in the Lamto reserve contributes to the maintenance of different subsets of the termite community.

Recent Research Indicates Plant Community Responses to Intensive Treatment Including Chemical Amendments

1989 ◽  
Vol 13 (3) ◽  
pp. 152-156 ◽  
Author(s):  
Benee F. Swindel ◽  
Joel E. Smith ◽  
Daniel G. Neary ◽  
Nicholas B. Comerford
Keyword(s):  
Plant Community ◽  
Loblolly Pine ◽  
Pinus Elliottii ◽  
Plant Species Richness ◽  
Moisture Gradient ◽  
Moisture Regime ◽  
Community Responses ◽  
Crown Cover ◽  
Competition Control ◽  
Pinus Taeda L

Abstract Plant community responses to several factors (planted species, competition control, and nutrients) that influence stand development were tested in a factorial experiment on a flatwoods Spodosol. A moisture gradient across replications, augmented by irrigation, permitted testing of afourth factor (moisture regime). There were differences between slash pine (Pinus elliottii var. elliottii Engelm.) and loblolly pine (Pinus taeda L.) crown development, but no response to moisture gradient. Pines and other plants responded dramatically to continuing competition control andrepeated fertilization. Nonpine crown cover was reduced from 100% on plots without herbicides to less than 10% on treated plots. Pine crown cover at 5 years averaged 73% with both fertilization and competition control versus 11% on control plots. Both pine and nonpine cover changed significantlyacross bed, furrow, and interbed niches, and niche interacted with chemical (fertilizer and herbicide) treatment. Competition control dramatically reduced plant species richness; modal number of species observed on 5 m transects was reduced from 10 on plots without herbicides to 2 on plotsrepeatedly treated. South. J. Appl. For. 13(3):152-156.

Impacts of nitrogen deposition on terrestrial plant diversity: a meta-analysis in China

2019 ◽  
Vol 12 (6) ◽  
pp. 1025-1033 ◽  
Author(s):  
Wen-Juan Han ◽  
Jia-Yu Cao ◽  
Jin-Liang Liu ◽  
Jia Jiang ◽  
Jian Ni
Keyword(s):  
Species Richness ◽  
Plant Diversity ◽  
Meta Analysis ◽  
N Deposition ◽  
Shannon Index ◽  
N Addition ◽  
Terrestrial Plant ◽  
Multiple Dimensions ◽  
Negative Effect ◽  
Experiment Duration

AbstractAimsWith the global atmospheric nitrogen (N) deposition increasing, the effect of N deposition on terrestrial plant diversity has been widely studied. Some studies have reviewed the effects of N deposition on plant species diversity; however, all studies addressed the effects of N deposition on plant community focused on species richness in specific ecosystem. There is a need for a systematic meta-analysis covering multiple dimensions of plant diversity in multiple climate zones and ecosystems types. Our goal was to quantify changes in species richness, evenness and uncertainty in plant communities in response to N addition across different environmental and experimental contexts.MethodsWe performed a meta-analysis of 623 experimental records published in English and Chinese journals to evaluate the response of terrestrial plant diversity to the experimental N addition in China. Three metrics were used to quantify the change in plant diversity: species richness (SR), evenness (Pielou index) uncertainty (Shannon index).Important FindingsResults showed that (i) N addition negatively affected SR in temperate, Plateau zones and subtropical zone, but had no significant effect on Shannon index in subtropical zones; (ii) N addition decreased SR, Shannon index and Pielou index in grassland, and the negative effect of N addition on SR was stronger in forest than in grassland; (iii) N addition negatively affected plant diversity (SR, Shannon index and Pielou index) in the long term, whereas it did not affect plant diversity in the short term. Furthermore, the increase in N addition levels strengthened the negative effect of N deposition on plant diversity with long experiment duration; and (iv) the negative effect of ammonium nitrate (NH4NO3) addition on SR was stronger than that of urea (CO(NH2)2) addition, but the negative effect of NH4NO3 addition on Pielou index was weaker than that of CO(NH2)2 addition. Our results indicated that the effects of N addition on plant diversity varied depending on climate zones, ecosystem types, N addition levels, N type and experiment duration. This underlines the importance of integrating multiple dimensions of plant diversity and multiple factors into assessments of plant diversity to global environmental change.

scholarly journals Impacts of Vegetation Control, Genetic Improvement and their Interaction on Loblolly Pine Growth in the Southern United States—Age 12 Results

2002 ◽  
Vol 26 (1) ◽  
pp. 37-42 ◽  
Author(s):  
Stacey W. Martin ◽  
Barry D. Shiver
Keyword(s):  
South Carolina ◽  
Loblolly Pine ◽  
Coastal Plain ◽  
Genetic Improvement ◽  
First Generation ◽  
Single Family ◽  
Genetic Stock ◽  
Vegetation Control ◽  
Mechanical Site Preparation ◽  
Competition Control

Abstract A designed study was established in the Coastal Plain of Georgia and northern Florida, and in the Piedmont of South Carolina, Georgia, and Alabama with the objectives of evaluating the impacts of first-generation genetic improvement and of combining genetic improvement and vegetation control on yields of loblolly pine. The two levels of competition control were either none, other than that provided by the operational mechanical site preparation, or complete competition control. Genetic treatments consisted of unimproved seed stock, bulk lot first-generation improved stock or single family first-generation improved stock. In terms of total volume, increases up to 45% (882 ft3/ac) and 39% (863 ft3/ac) were obtained from using complete vegetation control in the Coastal Plain and Piedmont regions, respectively. Improved genetic stock increased total volume an average of 11% (246 ft3/ac) to 16% (364 ft3/ac) in the Coastal Plain and 12% (277 ft3/ac) to 19% (445 ft3/ac) in the Piedmont for bulk lot and single families, respectively. For total volume, the effects of competition control and genetics were additive, indicating the managers should obtain the full benefit of these two treatments. In both regions, improved genetics significantly reduced the percent fusiform infection. In addition, no statistically significant differences were detected between bulk lot and single family plantings across all dependent variables. South. J. Appl. For. 26(1):37–42.

Early Results from an Old-Field Loblolly Pine Spacing Study in the Georgia Piedmont with Competition Control

1993 ◽  
Vol 17 (4) ◽  
pp. 193-196 ◽  
Author(s):  
L. V. Pienaar ◽  
B. D. Shiver
Keyword(s):  
Loblolly Pine ◽  
Basal Area ◽  
Planting Density ◽  
Yield Potential ◽  
Stem Volume ◽  
Annual Increment ◽  
Average Growth ◽  
Vegetation Control ◽  
Early Results ◽  
Georgia Piedmont

Abstract The study reported here provides information on the yield potential of improved loblolly pine seedlings planted on marginal agricultural cropland in the Georgia Piedmont with control of herbaceous competition. Early growth rates greatly exceed those in existing plantations established on cutover and mechanically site-prepared land in this region without additional control of competing vegetation. After 8 growing seasons, average tree height, average dbh, basal area per acre, and stem volume per acre were all influenced by planting density, but the mean annual increment of merchantable volume (trees 4.0 in. dbh and bigger to a 2.0 in. top diameter) at age 8 yr, for planting densities of 400 to 1000 trees/ac, was 230 ft³, or approximately 3 cords/ac/yr. This is more than twice the average growth rate in this region of cutover and mechanically site-prepared loblolly plantations without additional vegetation control. These results should be of particular interest to prospective participants in the Conservation Reserve Program (CRP). South. J. Appl. For. 17(4):193-196.

Loblolly pine growth response to herbaceous vegetation control at different planting densities

1999 ◽  
Vol 29 (7) ◽  
pp. 960-967 ◽  
Author(s):  
Harold Quicke ◽  
Glenn Glover ◽  
Ralph S Meldahl
Keyword(s):  
Loblolly Pine ◽  
Basal Area ◽  
Planting Density ◽  
Herbaceous Vegetation ◽  
Vegetation Control ◽  
Volume Yield ◽  
Volume Response ◽  
Adjustment Term ◽  
Pinus Taeda L ◽  
Positive Effect

Growth of Pinus taeda L., with and without control of competing herbaceous vegetation, was evaluated over 15 years at planting densities ranging from 747 to 2990 trees/ha. A height response to vegetation control of 0.9 m at age 5 decreased to 0.3 m at age 15. Convergence in the cumulative height between treated and untreated stands did not translate into converging basal area and volume yield. For 1500 and 2200 trees/ha, volume response to early vegetation control increased to age 15. For 800 trees/ha volume gains increased to age 12 and were stable between ages 12 and 15. Higher densities apparently captured more of the site resources made available through vegetation control. Age-15 volume gains for 2200, 1500, and 800 trees/ha were 71 (23%), 48 (17%), and 19 m3·ha-1 (8%), respectively. A separate adjustment term in height and basal-area models captured the short-term positive effect of vegetation control on height growth and longer term basal-area responses. Previously published height and basal-area models were modified to account for planting-density effects.

Stand level pine response to occupancy of woody shrub and herbaceous vegetation

1999 ◽  
Vol 29 (7) ◽  
pp. 979-984 ◽  
Author(s):  
Dwight K Lauer ◽  
Glenn R Glover
Keyword(s):  
Loblolly Pine ◽  
Basal Area ◽  
Pinus Elliottii ◽  
First Year ◽  
Shrub Cover ◽  
Herbaceous Vegetation ◽  
Vegetation Control ◽  
Competing Vegetation ◽  
Dominant Height ◽  
Stand Basal Area

The relationship between age-5 pine height and vegetation cover was estimated for loblolly pine (Pinus taeda L.) and slash pine (Pinus elliottii Engelm.) stands using regression analysis. This paper utilizes results from four locations of a vegetation control study that included herbicide treatments to control woody shrub and herbaceous vegetation. Age-5 average dominant height was predicted from first-year herbaceous cover, untreated first-year shrub cover, and fifth-year shrub cover. Dominant height increased 0.5 m for each decrease of about 30% in either first year herbaceous cover, untreated first-year shrub cover, or year-5 shrub cover. Lack of vegetation control on beds where vegetation was allowed to recolonize before planting reduced dominant height an additional 0.5 m. A competition index was constructed that estimates the difference between "potential" and actual age-5 pine height. Stand-level models were developed to link age-5 pine height and occupancy of competing vegetation to quadratic mean DBH, specific DBH percentiles, and stand basal area. The effects of interspecific competition on stand basal area and diameter percentiles could be accounted for through the effects of competing vegetation on dominant height except for treatments that did not control woody shrubs.

Sign in / Sign up

Export Citation Format

Share Document