scholarly journals Effects of fire retardant chemical and fire suppressant foam on shrub steppe vegetation in northern Nevada

1999 ◽  
Vol 9 (2) ◽  
pp. 115 ◽  
Author(s):  
Diane L. Larson ◽  
Wesley E. Newton ◽  
Patrick J. Anderson ◽  
Steven J. Stein
Keyword(s):  
Species Richness ◽  
Great Basin ◽  
Fire Retardant ◽  
Stem Density ◽  
Steppe Vegetation ◽  
Northern Nevada ◽  
Shrub Steppe ◽  
Fire Suppressant ◽  
Number Of Stems ◽  
Galling Insects

The objectives of this study were to determine the effects of fire retardantchemical (Phos-Chek G75-F*) and fire suppressant foam (Silv-Ex) application,alone and in combination with fire, on Great Basin shrub steppe vegetation. Wemeasured growth, resprouting, flowering, and incidence of galling insects onChrysothamnus viscidiflorus andArtemisia tridentata. These characteristics were notaffected by any chemical treatment. We measured community characteristics,including species richness, evenness, and diversity, and number of stems ofwoody and herbaceous plants in riparian and upland plots. Of these characteristics, only species richness and number ofstems/m2 clearly responded to the chemicaltreatments, and the response was modified by fire. In general, speciesrichness declined, especially after Phos-Chek application. However, by the endof the growing season, species richness did not differ between treated andcontrol plots. Acanonical variate analysis suggested that burning had agreater influence on community composition than did the chemical treatments.In general, riparian areas showed more significant responses to the treatmentsthan did upland areas, and June applications produced greater changes inspecies richness and stem density than did July applications.*Use of Trade Names does not imply endorsement by the U.S.Government.

scholarly journals The Species Richness of Vascular Plants and Amphibia in Major Plant Communities in Temperate to Tropical Australia: Relationship with Annual Biomass Production

2010 ◽  
Vol 2010 ◽  
pp. 1-17 ◽  
Author(s):  
R. L. Specht ◽  
M. J. Tyler
Keyword(s):  
Species Richness ◽  
Plant Communities ◽  
Stem Density ◽  
Air Temperatures ◽  
Annual Biomass ◽  
Tropical Australia ◽  
Number Of Leaves ◽  
Photosynthetic Potential ◽  
Number Of Stems ◽  
The Tropics

Aerodynamic fluxes (frictional, thermal, evaporative) in the atmosphere as it flows over and through a plant community determine the Foliage Projective Covers and eco-morphological attributes of new leaves developed annually in overstorey and understorey strata. The number of leaves produced on vertical foliage shoots depends on available soil water and nutrients, also ambient temperature, during this short growth season. Stem density (number of stems per hectare) and species richness (number of species per hectare) in the overstorey of major Floristic Groups are correlated with annual shoot growth (ASG, t ) in that stratum. Species richness in the overstorey increases in the climatic gradient from the arid to the humid zone as well as with increasing air temperatures (about C) from temperate to tropical Australia. Species richness in the understorey is highest in plant communities in temperate Australia, decreasing in the temperature gradient towards the tropics. As with other major plant and animal groups within an ecosystem, the species richness of Amphibia is correlated with the amount of solar energy fixed (per annum) by the major plant formation in the region—a photosynthetic potential determined by the foliage shoots (ASG, t ) produced annually in the overstorey.

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.

scholarly journals Soil-vegetation type, stem density and species richness influence biomass of restored woodland in south-western Australia

2015 ◽  
Vol 344 ◽  
pp. 53-62 ◽  
Author(s):  
Michael P. Perring ◽  
Justin Jonson ◽  
David Freudenberger ◽  
Rebecca Campbell ◽  
Michael Rooney ◽  
...  
Keyword(s):  
Species Richness ◽  
Western Australia ◽  
Vegetation Type ◽  
Stem Density

scholarly journals Galling Insects of the Brazilian Páramos: Species Richness and Composition Along High-Altitude Grasslands

2017 ◽  
Vol 46 (6) ◽  
pp. 1243-1253 ◽  
Author(s):  
Marcel S Coelho ◽  
Marco Antônio Alves Carneiro ◽  
Cristina A Branco ◽  
Rafael Augusto Xavier Borges ◽  
G Wilson Fernandes
Keyword(s):  
Species Richness ◽  
High Altitude ◽  
Galling Insects ◽  
High Altitude Grasslands

The structural characteristics and climatic and human impacts of deciduous oak forests in China

2021 ◽  
Author(s):  
Guoping Chen ◽  
Qiong Cai ◽  
Wenjing Fang ◽  
Yuhao Feng ◽  
Jiangling Zhu ◽  
...  
Keyword(s):  
Species Richness ◽  
Spatial Patterns ◽  
Tree Species ◽  
Structural Characteristics ◽  
Tree Height ◽  
Oak Forests ◽  
Oak Forest ◽  
Stem Density ◽  
Shrub Species ◽  
The Mean

Abstract Aims Deciduous oak forest is one of the typical vegetation types in temperate and subtropical mountain zones in China. However, the patterns and determinants of the structural characteristics of these forests remain poorly understood. Methods We investigated 682 oak forest plots across China to characterize the community structures of the oak forests and analyze the underlying factors controlling their spatial patterns. Important Findings Across all plots, the overall mean values were 13.7 cm, 10.0 m, 1468 stems/ha, and 24.3 m 2/ha for the diameter at breast height (DBH), height, stem density and total basal areas (TBA) of trees, respectively. The average species richness was 6 species/600 m 2, 10 species/100 m 2, and 4 species/1 m 2 for the tree, shrub and herb layers, respectively. As latitude increased, the mean tree height, stem density, TBA, tree species richness and shrub species richness decreased, and the mean DBH did not show a significant trend, while species richness of herbs increased significantly. Climatic and anthropogenic variables could explain more variations in mean DBH, mean tree height, TBA, tree species richness, shrub species richness than those in stem density and herb species richness. Further analysis showed that precipitation-related climatic factors were major factors shaping the spatial patterns of community structures. Our findings provide a basis for recognizing the biogeographic patterns of oak forest structures and their responses to global change in China.

Spatial and seasonal dietary patterns of the desert horned lizard (Phrynosoma platyrhinos): harvester ant specialist or generalist ant feeder?

2009 ◽  
Vol 87 (2) ◽  
pp. 112-123 ◽  
Author(s):  
T.A. Scott Newbold ◽  
James A. MacMahon
Keyword(s):  
Great Basin ◽  
Prey Availability ◽  
Prey Selection ◽  
Feeding Strategy ◽  
Harvester Ants ◽  
Shrub Steppe ◽  
Feeding Specialization ◽  
Phrynosoma Platyrhinos ◽  
Horned Lizards ◽  
Specialist Predators

A suite of factors including prey availability and prey defenses influence prey selection by consumers and ultimately define an animal’s feeding strategy (e.g., generalist or specialist). Here we examined the relationship between availability and selection of ants by the desert horned lizard ( Phrynosoma platyrhinos Girard, 1852) to test the hypothesis that P. platyrhinos are specialist predators on harvester ants, and to investigate which factors influence the prey preference of lizards. Variation in ant availability and lizard diets was assessed using 83 plots established along a Great Basin shrub–steppe bajada in northwestern Utah, USA. Across the study site, 14 of 20 ant species were represented in the lizard diet. However, 70% of that diet consisted of just two species. In contrast to previous studies, P. platyrhinos did not show a disproportionate preference for harvester ants. Instead, larger ants of any species (including harvester ants) were preferentially selected over medium-sized and smaller ants. These findings suggest that desert horned lizards demonstrate an opportunistic feeding strategy in which lizards select ants based on their body size and abundance. More generally, these results emphasize the importance of assessing predator response across naturally varying gradients in prey availability to evaluate feeding specialization.

Secondary forest succession in a tropical dry forest: patterns of development across a 50-year chronosequence in lowland Bolivia

2002 ◽  
Vol 18 (1) ◽  
pp. 53-66 ◽  
Author(s):  
DEBORAH K. KENNARD
Keyword(s):  
Species Richness ◽  
Tree Species ◽  
Stand Structure ◽  
Secondary Forest ◽  
Tropical Dry Forest ◽  
Basal Area ◽  
Forest Stand ◽  
Dry Forest ◽  
Stem Density ◽  
Mature Forest

Stand structure, species richness and population structures of tree species were characterized in 12 stands representing 50 y of succession following slash-and-burn agriculture in a tropical dry forest in lowland Bolivia. Estimates of tree species richness, canopy cover and basal area reached or surpassed 75% of mature forest levels in the 5-, 8-, and 23-y-old stands respectively. Total stem density of the 50-y-old stand was almost twice that of the mature forest stand. This rapid recovery may be due to a high percentage of sprouting tree species, potentially high seed fall into abandoned fields, or the disturbance history of the mature stand. The even-aged size-class structures, dominance of long-lived pioneers, and presence of charcoal and pottery shards in soils of the mature forest stand suggest it formed after a severe disturbance, possibly fire of anthropogenic origin.

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