THE CHANGES ON PINUS MONOPHYLLA DUE TO ELEVATION
Irving Granados
Department of Biiological Science
Saddleback College
Mission Viejo, CA 92692
There are distinctions amongst pinusmonophylla between elevations of 6270 and 9270 ft. in the White Mts. of California. The pinyon pines can have different respiration and photosynthetic rates at the elevations at which they are growing. Pinyons grow in hot, dry location on slopes or flat land. It was hypothesized that at a lower elevation the pinyon pinecones would be greater in size because of the dry region than pinyon pinecones at a higher elevation due to a more moisture condition. Twenty samples of pinyon pinecones (n=20) were collected to measure the height, thickness of the scale and the diameter of the pinyon pinecones at different elevation. The starting elevation was 6270 ft. and every 500 ft. a new sample of pinyon pinecones were collected. The average mean of the height measurement were statistically different where at 6270 ft. were taller and started to get smaller as we went higher in the mountain. (SEM, N=20), (p=0, one-tailed ANOVA, Boneferroni Correction). The mean of the scale thickness were statistically different where the initial elevation was greater and the final elevation was smaller ( SEM, N=20), (p=0, one-tailed ANOVA, Boneferroni Correction). The mean of the diameter showed a statistically difference from a greater diameter to a smaller size as the elevation increased ( SEM, N=20), (p=0, one-tailed ANOVA, Boneferroni Correction). Possible explanations might be the type of fertilization and soil nutrients concentration that allow the pinyon pine cones to fully develop at lower elevations, whereas, in a higher elevation the weather are more extreme for the pinyon pinecones to not fully developed to its full size.
Introduction
Pinusmonophylla is a semi-desert pine typical of the Great Basin but extending southwards in to Baja California and southeastwards across Arizona into New Mexico (Lanner, 1973). They are predominantly in drier regions and mountain slopes. The intensity and duration of drought increase downslope, this factor appears to offer at least a partial explanation of the differences in lower range limits. The significance of this difference among the species to endure soil drought is greatly magnified by the fact that the species of low altitude have the most rapid rates of root penetration. Not only are they better able to endure soil drought, but they are more likely to escape its influence (Daubenmire, 1943).They are also moderately to strongly shade intolerant, and dependent on disturbance, particularly fire, on productive sites for forest renewal.
The high elevation pines tolerate cold, arid sites with poor soils. (Tomback, 2010). Other related factors are the short growing season and low nutrients available at high elevations.With increasing elevation, and increasing actual evapotranspiration, the organic C, plant density, and the CO2 content of the soils increased (Amundson, Chadwick, Sowers, 1989).Too high a concentration of CO2 causes a reduction of photosynthesis. The environment and phytosociological characteristics of the pinyon woodland zone of the White Mountains of California are described and contrasted with those of other southwestern representatives of this vegetation type.
The pinyon woodland zone of the White Mts. is floristically allied to Nevada and parts of Utah. The White Mt. zone is unique in the high upper elevation limit it attains (9,500 ft) and in the low amount of average annual precipitation it receives (8 to 12 inches)(Andre, Mooney and Wright, 1965).In contrast to other pines, the surface tissue of pinyon cone scales (spermoderm) forms an irregular rim around the cone scales recess, instead of forming a wing...which holds the seed within the recess longer than it would otherwise remain in the cone (Lanner, Devender, 1988). The purpose of this work was to examine the height, diameter, and thickness of the scale variations from the pinyon pinecones from different elevation points from the White Mountains of California. And examineif the elevations causes some sort of variation amongst the pinyon pinecone factors.
Material and Method
Twenty pinyon pinecones were collected every five hundred feetat White Mts. in California (n=140) starting from the elevation of 6270 ft. to the top of the mountain at 9270 ft. on the 26 of November 2015. From each elevation twenty pinyon pinecones were collected from different tree locations to have variation. Each sample collection was place in a separate paper bag.
After eachsample (n=20) were collected from the seven different elevations of the mountain. Using a caliper device the measurements of the height, scale thickness and diameter of the pinyon pinecones (n=140) were taken. The height was measure with the c-clamp side of the caliper from bottom to the tip of the pinecone. Then the thick edge of the scale was measure using the same side of the caliper. And the diameter was measured from the bottom of the two longest sides of the pinyon pinecones. All data were transferred to MS Excel (Microsoft Corporation, Redmond, Washington) where all further statistical manipulation was performed (n=140).
Results
The average thickness of the pinyon pinecones scales between the elevations were statitiscallyless in the elevations from 6770 ft to 9270 ft.; especially the elevation of 9270ft compared to the elevation at 6270 ft. (p=0, one-tailed ANOVA, Bonferroni Correction).
The average height of the pinyon pinecones between the elevations were statitiscally less in the elevations from 6770 ft to 9270 ft. compared to the elevation at 6270 ft. At the elevation of 6270 ft. the height were greater in size(p=0, one-tailed ANOVA, Bonferroni Correction).
The average diameter of the pinyon pinecone between the elevations were statitiscally less in the elevations from 6770 ft to 9270 ft. compared to the elevation at 6270 ft. (p=0, one-tailed ANOVA, Bonferroni Correction).
Figure 1. The different elevation and the average mean of the pinyon’s thickness of scale. The average measurements of pinyon pinecones thickness of the scale were statistically less as the elevation increased, especially at 9270 ft. compared to the elevation of 6270 ft. (p=0, one-tailed ANOVA, Boneferroni Correction). Error bars are Mean SEM. =Statistically different from other groups.
Figure 2. The different elevation and the average mean of the pinyon’sheight. The average measurements of pinyon pinecones height were statistically less as the elevation increased, especially at 9270 ft. compared to the elevation of 6270 ft. (p=0, one-tailed ANOVA, Boneferroni Correction). Error bars are Mean SEM. =Statistically different from other groups.
Figure 3. The different elevation and the average mean of the pinyon’sdiameter. The average measurements of pinyon pinecones diameter were statistically less as the elevation increased, especially at 9270 ft. compared to the elevation of 6270 ft. (p=0, one-tailed ANOVA, Boneferroni Correction). Error bars are Mean SEM. =Statistically different from other groups.
Discussion
In this study, the data support the fact that pinyon pinecones were greater in size at a lower elevation than at a higher elevation, thus reavealing a significant difference in height, thickness of the scale and diameter amongst the elevation going up the mountain. At 6270 ft. the pinyonpinecones were larger in size. Some factors was that temperature was higher and was more of a dryer environment. Going up the mountain the amount of snow present was increasing and the size of the pinyone pinecones were almost similar to each other from 6770 ft. to 8770ft. Once reaching the top of the mountain at 9270 ft. the temperature was lower, and there was more snow present and the size of the pinyon pinecones were a lot smaller than the other elevations.
Literature Cited
Amundson, R, Chadwick, O and J.M. Sowers. 1989. A comparison of soil climate and biological activity along an elevation gradient in the eastern Mojave Desert. Oecologia 80(3): pp. 395-400.
Andre, G, Mooney, and R. D. Wright. 1965. The Pinyon Woodland Zone in the White Mountains of California. The American Midland Naturalist73(1): pp. 225-239
Daubenmire, R.F. 1943.Soil Temperature Versus Drought as a Factor Determining Lower Altitudinal Limits of Trees in the Rocky Mountains. Botanical Gazette 105(1):pp. 1-13
Lanner, Ronald. 1973. Natural Hybridization between Pinusedulis and Pinusmonophylla in the Amerian Southwest. pp108-116
Lanner, Ronald and Thomas VanDevender. 1988. The recent history of pinyon pines in the American Southwest. Ecology and biogeography of pinuspp171-180