Discussion
Reproduction and passing on genetic and behavioral traits to an offspring is a common fundamental to all the species on this planet. When studying forest ecology, it is crucial to study the proportion of individuals surviving at each stage of their growth as the lives and mortality experienced in a species population describes a characteristic of the species in question. In the case of American beech and sugar maple, their attempt to produce seeds is analogous to entering lottery, where every seedling has a potential chance of becoming a canopy but only some will survive and reach the canopy size; thus, becoming the fit ‘winners’. Our information shows that together, based on size class distribution, both the species display a ‘winner takes all’ pattern, which supports our hypothesis. The results showed a greater count for seedlings and short saplings than for tall saplings, sub-canopies and canopies. This is evident for a Type III survivorship curve. In Type III curve all individuals initially having a very low chance of survival. However, once the individuals pass their threshold age and survive, they live an advanced age. Only some individuals out the mast seeding production mature to become fully fit canopy trees. On the other hand, our hypothesis of canopy trees representing the bulk of the biomass was supported as the basal areas decreased going from growth stages of canopy to seedlings. This is evidence that once the individuals survive the bottleneck where there is high mortality of young individuals (seedlings), who are then considered as ‘losers’, will allow for the other larger size class individuals to flourish. Here, having considerable amount of dbh (diameter at breast height) accounts for greater surfac...
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These are very difficult questions for me personally to answer because I live in the Pacific Northwest, and I have seen the beauty of the old growth forests first-hand.
Zielinski, E. (2012, April 25). The Northwest Forest Plan. Retrieved from U.S. DEPARTMENT OF THE INTERIORBUREAU OF LAND MANAGEMENT: http://www.blm.gov/wo/st/en/info/history/sidebars/ecosystems/Northwest_Forest_Plan.html
Long-leaf pine areas have been converted to loblolly or slash pine plantations or severely fire suppressed. Urban development was a major cause of habitat loss in the early part of this century, as was logging.
Burton, Robert, ed. Nature's Last Strongholds. New York: Oxford UP, 1991. Print.
Introduction: When plants reproduce, size is highly correlated with reproductive output (Samson and Werk,1986). The struggle for reproductive survival among plants is the struggle to grow in the face of competition from neighbors. So the question this experiment asks is how competition affects the growth of plants. A plant growing in a nutrient-abundant environment free from competition will exhibit maximum growth potential and seed production (Watkinson,1983). But as the plant density increases and available resources become more limited, the decision must be made between continued growth or producing viable seed. I hypothesize that as Helianthus plant proximity becomes tighter, plant size and stem length will be effected negatively. For now my null hypothesis will be that plants grown in isolation will exhibit the same size and stem length as Helianthus plants grown under intraspecific competition.
Talbot, M. (1944, December 27). Site preparation as an aid to sugar pine regeneration. Retrieved from http://www.fs.fed.us/psw/publications/documents/psw_rn_os041/cfres_rn041.pdf
Many old-growth forests across the landscape of northern Lower Peninsula of Michigan contain a mixture of tree species rather than a monoculture. Many researchers have put forward ideas to explain the competition and co-existence of tree species in such communities. A theory explaining competition and co-existence between two species is gap regeneration. Gap regeneration is when a gap is created upon death of a plant individual and a new individual, sometimes of the same species as died and sometimes not dependent on environmental heterogeneity, takes its place (Kenneth Lertzman). Canopy gaps during gap regeneration can be explained by either reciprocal replacement or habitat preference . In a reciprocal replacement, seedlings of one species would be found predominately under large trees ...
Cary Institute of Ecosystem Systems, 2014. Web. The Web. The Web. 27 Feb 2014.
Landscape fragmentation can be characterized as a break up of a continuous landscape into more smaller, less-connected patches by roads, clearing for agriculture, commercial and residential development, and timber harvesting. Clear-cutting can break up mature, contiguous forest until the clear-cut area has regenerated to a point that it does not act as an ecological barrier to interior species or species that rely on continuous, mature forests. Much of the work that has sought to measure landscape pattern and habitat fragmentation comes out of the disciplines of conservation biology and landscape ecology (Theobald 1998). These disciplines are founded on the premise that landscape patterns strongly influence and are influenced by ecological processes (Forman and Godron 1986).
In the last decade, from the Rockies to New England and the Deep South, rural and suburban areas have been beset by white-tailed deer gnawing shrubbery and crops, spreading disease and causing hundreds of thousands of auto wrecks. But the deer problem has proved even more profound, biologists say. Fast-multiplying herds are altering the ecology of forests, stripping them of native vegetation and eliminating niches for other wildlife. ' 'I don 't want to paint deer as Eastern devils, ' ' said Dr. McShea, a wildlife biologist associated with the National Zoo in Washington, ' 'but this is indicative of what happens when an ecosystem is out of whack. ' ' The damage is worse than anyone expected, he and other scientists say. Higher deer densities have affected growth, survival, and reproduction of many plant species which have aesthetic, economic or ecological value. In some cases, many species of trees have also been shown to have reduced growth as a result of high deer density (Environmental Benefits of Hunting, 1). Deer prefer certain plant species over others and frequently feed on economically valuable tree species. For example, they prefer oak and sugar maple seedlings, as well as acorns, over less palatable species like American Beech and striped maple. Thus, less marketable species are more likely to survive to maturity,
[1] “Mixedwood Plains.” Canadian Ecozones. Toronto: n.p., n.d. N. pag. TDSB Online Library School Sites. Web. 13 Dec. 2013. .
The Western forests are drastically different from what they were like before the European settlement. In pre-European time, the forests were open and park-like with only 25-35 trees per acre surrounded by areas of open grasslands. One could easily ride a horse through the spacious forest. This, however, is not possible in today's forests. Today, for example the Ponderosa pine forests, have over 500 trees per acre, creating thick dense areas of trees, brush, and bushes (President Bush, 4). The pre-European forests were subject to frequent low inte...
Franklin, J. F., et al. (1981). In Ecological Characteristics of Old-Grow Douglas Fir Forest, (GTR PNW-118). Retrieved July 9, 2005, from USDA Forest Service Web Site: http://
By carelessly shifting around organisms, with their awesome genetic potential, we have caused major ecological disasters. Gone is the most important tree in the Northeast, the American Chestnut, our premier landscaping tree, the American Elm, and gone are huge tracts of productive fresh water marsh. Now these marshes contain only monocultures (only one species present) of purple loosestrife.
Thesis: Forests provide the earth with a regulated climate, strong biodiversity, and good nutrient rich soil for plants to strive on.