The purpose of the study was to determine if human modification has an effect on species co-occurrence in stream invertebrates using a combination three methods: experimentation, field survey, and analysis of null models. Researchers hypothesized that human habitat modification disrupts patterns of species co-occurrence. They also hypothesize that the observations will be consistent along spatial scales. It was assumed from prior research, completed by other researchers, that undisturbed communities would show negative species co-occurrence due to predation, competition, and habitat segregation. It was also assumed that disturbance to a habitat would weaken biotic interaction which is explained to lead to random associations between species. The background given efficiently explains everything that is needed to interpret the rest of the investigation.
Different scales were used to compare macroinvertebrate community assembly in natural and modified habitats. At the catchment scale, 32 reaches were studies. Seventeen drained pastured grassland and fifteen drained semi natural vegetation. Hand net collections were taken at 3 minute intervals. At the patch scale, communities in undisturbed substrate were compared with communities under attack by fine sediment due to upstream erosion. Eight streams and a total of sixty stream patches were sample using a surper-sampler. At the microhabitat scale, controlled in situ conditions were used to reproduce fine sediment deposition. Three streams with low loads of sediment were examined. Sixty five total trays full of natural substrate free of animals were used. They were placed at the predetermined sites. Twenty-one trays were used as control, 23 trays were treated with fin...
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...e not solid enough in this experiment to make any final ruling in either direction. The researchers point that most of the literature on this topic is comprised of looking for changes in species richness, abundance, and composition. They claim to have changed that with this research and they have shown that habitat modification can disrupt species co-occurrence but not relative abundance and changes in richness. They also point out that this contradicts current literature on the topic. There is still more research on the topic that needs to be completed. There values in species richness and relative abundance stayed close to one another but there were large variations seen at the highest sediment level. The p values were significant but as there is other literature that contradicts this point it is evident that more studies such as this need to be performed.
Purpose: The purpose of this lab is to investigate the various components of different ecosystems in a smaller representation and study the conditions required for the ecosystem’s sustainability as well as the connections between
The purpose of this lab was to discover how diverse the parking lot at Bunker Hill High School could be, by finding out the Shannon Wiener biodiversity index of the parking lot. The parking lot was used because it does not have much immigration and emigration of the cars. Using an actual ecosystem in the wild would be hard to control, what is immigrating and emigrating out of the experiment. The experiment shows how diverse the cars were, and this can show how diverse an actual ecosystem was during that time of the experiment. This then tells that diversity does matters because if everyone had the same kind of car, then no one would be different. However, if the students, faculty, and guests had a variety of cars in the parking lot, which made the experiment more diverse in the parking lot or the community of cars.
Fish habitat is the underwater world which many people do not see. It is just like the world that people live. Fish and plants reproduce, eat, and live in this environment, and even face challenges such as invasive species. It is said that “Invasive species are non-native species that threaten the diversity or abundance of native species due to their uncontrollable population growth, causing ecological or economic impacts” (“Invasive” par. 1). Vegetation plays a big role for fish habitat and for a lake itself. Aquatic habitat provides living space for not only fish but also for many aquatic insects. These insects then in turn provide fish and other species of animals with food (“Native” par. 4).
Darters are an important part of any stream ecosystem. They generally play the crucial role of secondary consumers, comprising most of their diet of soft-bodied animal...
middle of paper ... ... The Web. 28 July 2011. http://ec.europa.eu/environment/life/project/Projects/index.cfm?fuseaction=home.showFile&rep=file&fil=SMURF_otter.pdf. Community Ecology.
The processes of predation affect virtually every species to some degree or another. Predation can be defined as when members of one species eat (and/or kill) those of another species. The specific type of predation between wolves and large ungulates involves carnivores preying on herbivores. Predation can have many possible effects on the interrelations of populations. To draw any correlations between the effects of these predator-prey interactions requires studies of a long duration, and statistical analysis of large data sets representative of the populations as a whole.
In a marine environment, different types of sediments are associated with varying depths of ocean water. Sediments accumulate over time and are deposited by water, air, or both. ...
Evaluation: If this experiment was to be redone then more diverse oceanic life would have to be used playing different roles in the water. The experiment performed showed a small projection of the ocean’s course if pH levels rise but by adding more confounding variables then maybe the outcome may have been different. If another researcher is to replicate this experiment it is optimal if they did several different trials to see if the same result occurs like the one just performed.
...sica Leahy, and Kathleen Bell. "Interactions between Human Communities and Estuaries in the Pacific Northwest: Trends and Implications for Management." Estuaries. 26.4 (Aug., 2003): 994-1009 . Print.
Landscape fragmentation contributes to loss of migratory corridors, loss of connectivity and natural communities, which all lead to a loss of biodiversity for a region. Conservation of biodiversity must include all levels of diversity: genetic, species, community, and landscape (CNHP 1995). Each complex level is dependent upon and linked to the other levels. In addition, humans are linked to all levels of this hierarchy. A healthy natural and human environment go hand in hand (CNHP 1995). An important step in conservation planning, in order to guarantee both a healthy natural environment as well as a healthy human environment, is recognizing the most endangered elements.
A statistic released by the Marine Science Education Project of the Indonesian Ministry of Higher Education States that “…Reefs subject to land-based pollution (sewage, sedimentation, and or industrial pollution) show 30–50% reduced diversity at 3 m, and 40–60% reduced diversity at 10 m depth relative to unpolluted comparison reefs in each region.” This statistic is alarming because it shows just how much pollution can affect a certain environment. Not only does it affect the environment but it also affects animals, plants and people.
The aim of this study was to 1) determine how the proportion of habitat patches occupied influenced the change in patch incidence and 2) investigate how the extinction and migration rates influence the amount of patches occupied.
On the first level, when foreign, but previously non-invasive species is first introduced to a new area, the new species may play a role in a community that was previously unfulfilled; it may fill a vacant niche in the ecosystem. Originally this new species may be seen as a useful contributor to its new surroundings because it has only (temporarily) increased biodiversity in the area (Meinesz, 2003).
In order to find the stream quality of a river, a scientist must look at the stream ecology. The stream ecology is the study of the organisms and their dwelling. First, the scientist will look at the organisms living in a certain ecosystem, say the Jordan River, and rate them intolerable to tolerable. The toleration is based upon whether the organism can survive in highly polluted areas or if they will die. The current, or stream flow, also must be taken into account. Certain creatures live in the shallows, unmoving pockets, while others live out in the open water. Creatures can also be found in riffles, or small rocky area similar to a water fall. The differences between pools and riffles play a large part in the organisms as well as streams
Lotze, Heike K., Marta Coll, Anna M. Magera, Christine Ward-Paige, and Laura Airoldi. "Recovery of Marine Animal Populations and Ecosystems." Trends in Ecology & Evolution 26.11 (2011): 595-605. Print.