Introduction
In the past 200 years salt cedar (Tamarix spp.) have been encroaching in western waterways. Salt cedar was introduced accidentally as an ornamental that escaped control, and purposefully as a bank stabilizer (Sher, Marshall, & Taylor, 2002). The species in the Tamarix genus where thought to be very useful until it was observed that they displaced native genus’s Salix (willow) and Populous (aspen, and popular) trees. It is now considered a weed in 7 western state (Zouhar, 2003). Effects of Tamarix presence and invasion have been sensed in terms of native tree species displacement, loss of biodiversity, water loss, and salt accumulation. Not only is there effect on abiotic factors but on native animal species, such as the endangered Southwestern Willow Flycatcher.
Many management strategies have been employed in trying to control Tamarix spp in the west. Strategies include bio-control, herbicide, mechanical treatments, and changes in water management practices. Notwithstanding the undesired presence it is important to understand the reason that the plant is there, the physiology of the plant, and what has been successful in restoring the native comminuties in its natural stable state of native species. Herein we will explore the plants physiology, long held preconceptions on why salt cedar has invaded, some management techniques and considerations for present and future research and control. In order to understand how to make the symptom of salt cedar invasion occurred it is important to understand the characteristics that make the plant survive and what the underlying cause of the invasion may be. In this report Tamarix species will be pointed out in specific examples but more often general characteristic about membe...
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...a trailii extimus). Albuquerque, New Mexico.
Sher, A., Marshall, D., & Taylor, J. (2002, June). Establishment Pattern of Native Populus and Salix in the Presence of Invasive Nonnative Tamarix. Ecological Applications, 12(3), pp. 760-772.
Taylor, J. L. (2000). Populus fremontii. Retrieved from U.S. department of Agriculture, Forest Service, Rocky Mountain Reaserach Station, Fire Science Laboratory: http://www.fs.fed.us/database/feis/plants/tree/popfre/introductory.html
Vandersande, M. W., Glenn, E. P., & Walworth, J. L. (2001). Tolerance of five riparian plants from the lower Colorado River to salinity drought and inundation. Journal of Arid Environments, 49, 147-159. doi:10.1006
Zouhar, K. (2003). Tamarix spp. Retrieved from U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station: http://www.fs.fed.us/database/feis/plants/tree/tamspp/all.html
The ecological effects of wildfires on Yosemite are among some its greatest benefits. Trees like Bishop Pines and Sequoias have evolved in such a way that their seeds will only open when exposed to high temperatures. The fires also help to clear out dead leaves and weeds, thereby making sunlight accessible to new plants and increasing their chances to germinate (Marder). Wildfires are so essential in areas like Yosemite that over millions of years, plants have developed strategies to be successful in this type of environment. For instance, giant sequoias have developed a thick layer of fire-resistant bark. This bark is “the main explanation for tree survival in intense fires” (Gignoux, Colbert, and Menaut). Fire makes the soil fertile and redistributes the nutrients evenly so that the next generation of trees can cover more space. The fires have helped...
Invasive species as a whole have become a nuisance to many habitats and ecosystems around the world. What defines an invasive species is the following. It must be a species that is foreign to the habitat it resides in, have no natural predators which allow it to reproduce in such a rapid manner, and out compete native animals of food and shelter (Rosenthal 2011). These characteristics are what create such high populations of these invasive species in various habitats around the globe.
Australia is a land of rather extreme weather conditions and widely diverse climates that force the vegetation living there to adapt in many interesting ways. Australia is the driest continent, and biomes such as grasslands and savannas are prime sources of widespread catastrophic fires. The plants that grow in the vast arid and semi-arid regions of Australia are prone to fires simply because of the desert climates that they grow in. High temperatures combined with low fuel moisture contents, little humidity and drying winds that sweep across the landscape encourage many of the plants living in these areas to burst into flames at fairly frequent intervals. Serotinous cones, protective bark, intricate underground recovery systems, unique seed distributions and even the necessity of fire for reproduction are just some of the amazing ways that the major plant families which grow in these fire-prone areas have learned to adapt to their environments.
Invasive species are non-native organisms that occupy habitats and disrupt the natural ecological cycles of the habitat. They threaten the biodiversity of an ecosystem and are biological pollutants Invasive species introduced into new habitats usually maximize their reproduction in their new home and crowd out native species. Their lack of natural predators in their new community allow for a proliferation in growth and expansion as a result of their abundant food supply. Once they are established, invasive species can rarely be eliminated because their new habitat is favorable for their survival.
Perhaps the most devastating disregard of the Fraser Valley’s biodiversity was the draining of Sumas Lake to create farmland, resulting in the loss of habitat and the extirpation of endemic species. As it was originally intended to be, the Fraser Valley was a “perhaps unparalleled ecosystem” (Rosenau, p. 55), with bountiful wetlands and remarkable biodiversity. The European settlers 150 years ago considered it to be “wasteland” (Thom, p. 172), certainly uninhabitable and a breeding ground for mosquitoes, so the most logical thing to do would be to drain the body of water once known as Sumas Lake...
The Chaparral biome is most common in latitudes of 35 degrees North and is seen most often in Southern California. Chaparral plants have special adaptations that help them deal with the unique climate. In addition there are specific characters of a Coastal Sage Scrub and Chaparral community that would help in their identification. Both of these topics, secondary succession, endangered plant species, and the importance of habitat preservation will be discussed.
This vegetation also provides much cover for fish. The aquatic plants provide a great source of food supply and act as a nursery for young fish (“Native” par. 5). Vegetation serves many purposes in fish habitat; besides keeping fish safe. It also helps keep the lakes clean. Aquatic plants cycle the water and help absorb pollutants. Another great benefit of these aquatic plants are that they help hold sediment and the banks of the lakes in place while providing oxygen into the water (“Invasive” par. 7-8). Unfortunately invasive species are destroying such vegetation. The Common Carp or “Cyprinus carpio” is one such fish that is causing great damages to lakes all around the world.
The Great Basin of North America and Wyoming specifically, is known for its arid and semi-arid environment, as well as prolonged and sometimes severe droughts. Drought is the prolonged and abnormal deficiency of moisture with the concomitant decline in runoff to a level significantly lower than usual (Guldin 1989). The history of droughts in Wyoming has been uncertain in the past, but recent studies of tree rings in the Big Horn Basin of Wyoming have given insight to droughts as far back as 1260A.D. (Gray et al. 2004). Looking at tree ring records in Douglas fir (Pseudotsuga menziesii) and limber pine (Pinus flexilis) trees, Stephen Gray and his colleagues discovered that droughts which have been experienced in Wyoming since the 1750's, are weak in severity and length when compared to those since. The most severe drought period in Wyoming’s history occurred from 1262 to 1281. The droughts of the 1930’s and 1950’s, which have been used as benchmarks for all other droughts in the United States in recent times (Woodhouse et al. 2002), are ranked 149th and 28th respectively in comparison (Gray et al. 2004). The five top ranking droughts for 10, 15, and 20 year periods are all prior to the 1800’s, with the four driest single years being 1263, 1274, 1278, and 1280 (Gray et al. 2004). This indicates a change in precipitation patterns in the Big Horn Basin area of Wyoming since the 18th century, as all recent droughts have been mild when compared to those of Wyoming’s past.
Since the early 1900's a disease known as Chestnut Blight has infected many American Chestnut trees and causing their removal from forests. A greater look at the history of this fungus as well as the mechanisms of action will allow us to learn on how to preserve the American chestnut. At one point, the American chestnut was virtually eliminated. With the help of government acts and conservation agencies, the American chestnut is slowly growing back in population. Two methods of restoration of the chestnut include a hybridization and the use of hypovirulant strains. This issue shows a variety of interest from ecologists to those in the timber industry who cannot lumber Asian species of chestnut primarily because of their size.
Timmons, J. B., Alldredge, B., Rogers, W. E., & Cathey, J. C. (2012). Feral hogs negatively affect native plant communities. Informally published manuscript, Texas AgriLife Extension Service, Texas A&M , College Station, TX, Retrieved from http://feralhogs.tamu.edu/files/2010/04/feral-hogs-native-plants.pdf
Munger, Gregory T. "Lythrum Salicaria." Lythrum Salicaria. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory, 2002. Web. 02 Feb. 2014.
Americans today tend to believe that the Colorado River drought has been a recent occurrence, although drought relief strategies have been implemented since early 1997. To summarize, in the book The Colorado River Basin Drought Planning and Organizations, Colorado is named as the original state to acquire a drought relief plan. For instance, various assume water levels are diminutive in the Colorado and blame is due to the previous ten years of drought throughout the United States. Although it is true that water levels are at a record low, initial plans in the early 1920’s to introduce manufactured structures into the water basin is the original reason Colorado’s water system began to be compromised. It follows, then the supplementary natural
In 1996, the Asian Longhorn Beetle made its way into the New York and New Jersey creating the decimation of the forests. The Asian Longhorn Beetle has so far caused the cutting of over 10,000 trees in New Jersey, and quarantine of 109 miles in New York today . The spread of this foreign beetle has created great impacts on the environment. The Asian Longhorn Beetle is an invasive specie, a harmful specie from another locations, mainly other countries, that has ended up in a foreign habitat. As time has progressed, invasive species have continued to come into our environment more frequently creating many unforeseen consequences. The relationship of invasive species within the United States’ environment and ecosystem has been changing ever since the arrival of the Europeans in the 1700s to present day. Due to these encounters with other species whether harmful or neutral, the majority, if not all, of the United States has been affected with the threatening encroachment of native species due to the industrialization of waterways and transportation.
Invasive species, (also known as invasive alien species or simply alien species) are defined as any organism (plant, animal, pathogen, or other living thing) that is alien (non-native) to an ecosystem, which can cause adverse economical, ecological, or health effects to native species and/or humans. The roots of these problems all stem from the massive negative ecological impact these organisms are having on the environment (CBD, 2009). For all animal extinctions where the cause is known since the 1600’s, invasive alien species have been a contributing factor 40% of the time (CBD, 2006); the second most contributing factor to extinctions after loss of habitat (GC, 2013). By eliminating native species through competition for resources, predation, and transmittal of disease, invasive species continue to reduce biodiversity in almost all ecosystems around the world (CBD, 2009). In the future, this problem may worsen, and if no action is taken, could lead to a cascading ecological problem so large that whole communities or even ecosystems could collapse.
...eld observation and laboratory experiment to determine whether or not allelopathy was the factor contributing toward succession in abandoned agriculture land. The researchers conducted laboratory bioassays and compared the results to the field. Looking at leaf extracts, long term successional data, germination rates in the lab, and field observations to conclude that goldenrod succession was not due to allelopathic effects. Furthermore, the inhibitor chemicals have more of an impact in control settings and not in the field, which was within their native range. Their theory was that soil organisms metabolized the allelochemicals in such a rapid manner that the concentrations decreased and effects minimized. On another note, allelopathy has been shown in other studies to have contributed toward invasiveness for Solidago Canadensis in Europe (Pisula & Meiners 2010).