Wood (delta)^(13)C as a Measure of Annual Basal Area Growth and Soil Water Stress in a Pinus Strobus Forest

Ecology ◽  
1995 ◽  
Vol 76 (5) ◽  
pp. 1581-1586 ◽  
Author(s):  
S. G. McNulty ◽  
W. T. Swank
Keyword(s):  
Water Stress ◽  
Soil Water ◽  
Basal Area ◽  
Pinus Strobus ◽  
Soil Water Stress ◽  
Basal Area Growth ◽  
Area Growth

Derivation of a competitive index for individual trees from seasonal growth patterns

1984 ◽  
Vol 14 (2) ◽  
pp. 266-270 ◽  
Author(s):  
Frederick W. Smith ◽  
David R. M. Scott
Keyword(s):  
Soil Water ◽  
Leaf Area ◽  
Basal Area ◽  
Growth Patterns ◽  
Seasonal Growth ◽  
Competitive Index ◽  
Primary Mechanism ◽  
Basal Area Growth ◽  
Area Growth ◽  
Individual Trees

A competitive index for lodgepole pine (Pinuscontorta Dougl.) trees in central Oregon is developed from seasonal basal area growth and an indirect estimator of foliar leaf area. Differences in seasonal basal area growth and the ratio of basal area growth to sapwood basal area between trees with and without neighbors are used to document growth reductions owing to the proximity of competing individuals. A regression between basal area growth and sapwood basal area (an estimator of leaf area) is used as a predictor of maximum potential basal area growth for trees growing free of competition. The competitive index is determined as the ratio of actual to potential basal area growth for individual trees. This index standardizes growth against differences in tree size and site conditions. Plant and soil water relations are considered as possible mechanisms of competitive interaction. Moderate minimum seasonal values of predawn leaf pressure potentials (−0.76 to −0.92 MPa) and minor differences between trees in different competitive classes led to the conclusion that soil water may not be the primary mechanism of competition on this site.

scholarly journals Potassium Application Positively Modulates Physiological Responses of Cocoa Seedlings to Drought Stress

Agronomy ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 563
Author(s):  
Esther Anokye ◽  
Samuel T. Lowor ◽  
Jerome A. Dogbatse ◽  
Francis K. Padi
Keyword(s):  
Water Stress ◽  
Soil Water ◽  
Chlorophyll Content ◽  
Electrolyte Leakage ◽  
Seedling Survival ◽  
Biomass Accumulation ◽  
Biomass Partitioning ◽  
Chlorophyll Content And Fluorescence ◽  
Physiological Functions ◽  
Soil Water Stress

With increasing frequency and intensity of dry spells in the cocoa production zones of West Africa, strategies for mitigating impact of water stress on cocoa seedling survival are urgently required. We investigated the effects of applied potassium on biomass accumulation, physiological processes and survival of cocoa varieties subjected to water stress in pot experiments in a gauzehouse facility. Four levels of potassium (0, 1, 2, or 3 g/plant as muriate of potash) were used. Soil water stress reduced plant biomass accumulation (shoot and roots), relative water content (RWC), chlorophyll content and fluorescence. Leaf phenol and proline contents were increased under water stress. Additionally, compared to the well-watered conditions, soils under water stress treatments had higher contents of exchangeable potassium and available phosphorus at the end of the experimental period. Potassium applied under well-watered conditions reduced leaf chlorophyll content and fluorescence and increased leaf electrolyte leakage, but improved the growth and integrity of physiological functions under soil water stress. Potassium addition increased biomass partitioning to roots, improved RWC and leaf membrane stability, and significantly improved cocoa seedling survival under water stress. Under water stress, the variety with the highest seedling mortality accumulated the highest contents of phenol and proline. A significant effect of variety on plant physiological functions was observed. Generally, varieties with PA 7 parentage had higher biomass partitioning to roots and better seedling survival under soil moisture stress. Proportion of biomass partitioned to roots, RWC, chlorophyll fluorescence and leaf electrolyte leakage appear to be the most reliable indicators of cocoa seedling tolerance to drought.

Field Notes: Predicted Vs. Actual Basal Area Growth in West Virginia

1988 ◽  
Vol 5 (3) ◽  
pp. 221-222
Author(s):  
Arlyn W. Perkey ◽  
Kenneth L. Carvell
Keyword(s):  
West Virginia ◽  
Basal Area ◽  
Basal Area Growth ◽  
Area Growth ◽  
Field Notes

A New Index Representing Individual Tree Competitive Status

1973 ◽  
Vol 3 (4) ◽  
pp. 495-500 ◽  
Author(s):  
James A. Moore ◽  
Carl A. Budelsky ◽  
Richard C. Schlesinger
Keyword(s):  
Spatial Distribution ◽  
Strong Correlation ◽  
Basal Area ◽  
Tree Size ◽  
Competition Index ◽  
Individual Tree ◽  
Silvicultural Practices ◽  
Basal Area Growth ◽  
Hardwood Species ◽  
Area Growth

A new competition index, modified Area Potentially Available (APA), was tested in a complex unevenaged stand composed of 19 different hardwood species. APA considers tree size, spatial distribution, and distance relationships in quantifying intertree competition and exhibits a strong correlation with individual tree basal area growth. The most important characteristic of APA is its potential for evaluating silvicultural practices.

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