With global warming occurring and the climate changing it is important to be able to predict the changes that will occur and the effect that they will have. To forecast the change in temperature that will occur it is useful to understand previous temperatures. In high latitude climates humans only have short term temperature records so the distribution of chironomids is used to figure out the previous climate. The chironomids are non-biting two-winged flies (Insecta: Diptera: Chironomidae 7) that spend much of their life cycle as aquatic larva and are abundant in fresh water ecosystems. Chironomids are used in paleoecological studies as they have a relatively short life cycle, the adults are mobile, and have a head capsule that is preserved …show more content…
in lake sediment (Walker, 1987). The mobility and short life cycle cause chironomids to be highly responsive to climate change thus their distribution reflects the previous climate. While not all of the literature on the distribution of chironomids was used to judge the previous temperature there were some aspect of the climate that were being examined.
Whether it was the history of northern American lakes, the tree line that previously existed, or the previous temperature of the lake chironomids represented the previous climate very accurately. It was found in one study that 67-76% of the chironomid’s distribution was determined by the surface water temperature (Lotter el al., 1999). This shows that temperature is the main factor that influences the population of different types of chironomids. The other factors that were examined were lake productivity, oxygen content of the hypolimnion and sediments, water properties and water temperature (Walker, 1987). All these dimensions of chironomids habitat effected their population at the different lakes each study tended to look at. As well as different amounts of chironomids being found at each lake, different species would be found as well. By understanding which chironomids were in which lakes, scientists can then understand the environmental factors at the time that permitted the species to live in the abundance it was found to be …show more content…
in. The research sites all tended to be in high latitudes.
They were chosen to be here as the temperature is cold enough to affect the range in which the different species of chironomids could live. Most of the research of the distribution of chironomids has taken place in the northern United States and northern Europe. While some studies have been conducted in Canada more are needed, as this is an area of interest for predicting climate effects on the United States lakes when colder climate existed. As well as a lack of research in Canada more can be done in the United States and Europe as more data will allow for more accurate models to be constructed off the effect of temperature and other climate effects on the chironomids spices present. With better models then more accurate inferences on the climate can be made and applied to provide researchers with a better understanding of the previous climate conditions.
The areas that have been studied have often been chosen due to the lakes and the surroundings. Different types of vegetation allowed aspects such as the tree line to show how they effected the chironomids populations compared to tundra. Another aspect of the lakes that have been examined was the fact that they did not stratify. Due to this trait the surface temperature will reflect the overall temperature of the
lake. Currently very little research of chironomids has been done in the southern hemisphere. What has been done has not looked at the distribution of chironomids to examine the previous climate. This is partly due to the fact that the scientists that specialize in the field do not live in the southern hemisphere and there is still more information to be found and expanded on for the northern hemisphere lakes. The overall trend of the research data collected shows that different species can survive in different temperatures as latitude increases. In general the species of chironomids tended to be broken up into in relative warm lakes, temperate lakes that do not extend beyond the artic tree line, diluted lakes, and high saline lakes. Each study showed slightly different species being found in each category due to the surrounding feature of the lake. Overall the same species were being found in each range as the climate was relatively similar. Some of the research conducted an intercontinental compassion between the distribution of chironomids in North America and Europe (Lotter el al, 1999). The results were not as consitant as a singular study as the species fond in different climates varied more than in one region. While all the scientists collected their data slightly differently a main method was similar. They consisted of collecting surface sediment samples, measuring the water chemistry and physical variables of the lake, then the lake sediment was deflocculated on KOH solution, heated, sieved, rinsed, and chironomid head capsules were identified into the eleven sub famlies. All the papers based this method off (Walker, 1987 7) as he created the method. The fact that this is an old method does not take away from its validity as it is allowing the head capsules to be identified correctly and provides consistency in the research over the years. Each method was slightly different as based on the sediment at the site a different size sieve would be more effective to use. Other than these small changes there were some larger differences in the water quality sampling and temperature measuring. To sample the water required accessing the lake, which could be very difficult and was impossible to do for 50 lakes at the same time. Because of this problem the water sampling was not taken at the same time at each lake. Measuring the temperature in the important summer months was also a problem as access was once again a problem. In some cases the temperature was personally taken, in others it was done by a GPS, and in others it was averaged out using previous records. Another difference was whether air temperature or water surface temperature was measured. There seamed to be a split of half the research on the distribution of chironomids measuring air temperature and the other half measuring water surface temperature. When considering the research on the distribution of chironomids it is important to understand that a lot of the original research was conducted accurately and represents the trends that current research is finding. Now more aspects of the climate are being looked at to determine other factors that effect chironomids and to allow better understanding of the climates that were present when the chironomids were deposited in the lake sediment.
After results, it was concluded that isopods prefer normal temperature conditions over warm conditions. We created these environments by adding water onto filter papers with the accounted for temperature measurements. The reason for the results could be seen in a usual isopod environment, it is usually dark, fresh, and moist, and the normal water temperature being the closest to that was the reason for their choosing. The Isopods seemed to locate the appropriate environment by the use of their antennas. For the investigation the normal water and warm water temperatures were independent variables. The observations were the control. The isopods behavior served as the dependent variables. The isopod behavior would be classified as movement in response to a cooler temperature environment taxis. All in all the hypothesis, “If the isopods are exposed to normal and warm temperatures then the normal temperature will be preferred” proved to be
United States Department of the interior Fish And Wildlife Service, . North American Fauna. 2012.
Canada is a very large country, with areas of land in various climate regions, and land regions, thus having many ecozones that differentiate from another. The most populated ecozone in Canada is the Mixedwood Plains; the ecozone we are located in, named after the mixedwood forests that are native to the area. The Mixedwood Plains is one of the smallest of the Canadian ecozones, spanning only 175 963 kilometres squared. The Mixedwood Plains is bordered by three of the great lakes on the southern side of the ecozone, and comes up along the St Lawrence river to southern Quebec, and fills the tip of Ontario. It has rolling plains and small rock formations and escarpments. The Mixedwood Plains contains over half of the Canadian population as it contains some of Canada’s largest cities, including Toronto, Ottawa, Montreal, and Windsor. The Mixedwood Plains has a relatively temperate climate with summers ranging an average temperature of 18o c – 22oc and winters ranging from -3oc - -110c.[2] Native mammals to the ecozone are black, brown and grizzly bears, grey wolves, coyotes and foxes, raccoons, squirrels, and other small mammals. Avian species include brown sparrow, hawks, crows, cardinals and bluejays. Fish are bass, trout, carp and pike. The Mixedwood Plains is made up of about 40% water, and contains over 20% of the worlds freshwater. One of the major problems in the world today is freshwater shortage. Because we have ample supply, we don’t notice, but much of the world is short on water. There are more water resources, but one of the largest is being quickly polluted and populated by invasive species .
The re-wilding of North America is basically a conservation strategy (Donlan 2005), aimed at restoring the Pleistocene era (Donlan 2005, Rubenstein et al. 2006). This could be achieved by reintroducing African and Asian megafauna, these species are phylogenetically known to be direct descendents of the extinct Pleistocene species or animals of similar taxa (Donlan 2005, Rubenstein et al. 2006). Re-populating North America is essential for both ecological and evolutionary potential (Donlan 2005) and also economic gain (Donlan 2005, Rubenstein et al. 2006). In this paper I will be discussing the main arguments presented by two papers regarding the Pleistocene North America re-wilding. The first paper is written by Donlan (2005), it is a commentary paper in which he proposes the plan of re-wilding North America based on his opinions. The second paper is by Rubenstein et al. (2006), it is a research paper where he outlines some facts contrary to Donlan (2005)’s paper, unlike Donlan (2005)‘s paper his arguments were supported by variety of recent Scientific published papers which are relevant to the topic discussed.
15. Magers, Vince. Ichthyology’s Golden Age. Missouri Conversationist, Volume 60, Number 9, Sept 1999. http://www.conservation.state.mo.us/conmag/1999/09/6.html
... and the collection of wild plant foods. This variety may be the result of adaptations to changed ecological conditions associated with the retreat of glaciers, the growth of forests in Europe and deserts in N Africa, and the disappearance of the large game of the Ice Age. Characteristic of the period were hunting and fishing settlements along rivers and on lake shores, where fish and mollusks were abundant.
http://eaglenet.lambuth.edu/facultyweb/science/biology/RCook/community%20ecologyS10.pdf. Impacts on the Biodiversity. Quebec Biodiversity Website -. Web. The Web.
The climate of the tundra is characterized by harsh winters. The average temperature in the tundra area is about –27 degrees. But what is even worse are the long night. At nights the lowest temperture recorded was –67.36 degrees. There are even times in the year when the sun doesn’t come up for days. In the tundra we have little snow and even less rainfall. The rainfall is about a quarter inch in a yearly rainfall. Even though the tundra’s winters are long a harsh there summers are the shortest season of all. Do to the terrible weather and climate in the tundra their animals and plant life is very limited.
The Pleistocene epoch is a well-known time period thanks to the glorification of now extinct megafauna as well as the proximity to our current epoch. Through the rapid climate changes and glaciation that occurred many times during this epoch, the fauna
The Tundra suffers a very harsh climate. Because of this fact most of the area
Larry V. Benson et al. ( 2006) Possible impacts of the early 11th-middle-12th, and late 13th- century droughts on western Native Americans and the Mississippian Cahokians. Quaternary Science Reviews. , 26(2007) 336-350.
"The Consequences of Global WarmingOn Wildlife." Consequences of Global Warming. N.p., n.d. Web. 21 Feb. 2014. .
In many parts of the world, ecosystems’ temperatures begin to rise and fall to extreme levels making it very difficult for animals and plants to adapt in time to survive. Climate has never been stable here on Earth. Climate is an important environmental influence on ecosystems. Climate changes the impacts of climate change, and affects ecosystems in a variety of ways. For instance, warming could force species to migrate to higher latitudes or higher elevations where temperatures are more conducive to their survival. Similarly, as sea level rises, saltwater intrusion into a freshwater sys...
“Climate change: How do we know?” NASA. NASA n. d. n. pag. Web. 28 November
Climate Change is any substantial change in climate that lasts for an extended period of time. One contributor to current climate change is global warming, which is an increase in Earth’s average temperature. Plants and animal species throughout the world are being affected by rising temperatures. Many plants are flowering earlier now than they once did; animals, such as the yellowbellied marmot, are emerging from hibernation earlier; and many bird and butterfly species are migrating north and breeding earlier in the spring than they did a few decades ago, all because of slight changes in temperature cues. (Shuster)