Dependency for food, clothing and shelter by the human society from the environment is invaluable. As population increase the consumption of basic necessities both locally and globally increases. The continuous supply of food and food components from the environment cushions societal disturbances from lack of basic needs. Therefore the importance of a healthy environment has gradually grown during the last few decades as support from human and animal life is imperative in the expanding and advancing environment (Grimsditch, 2005).
Environmental pollution and industrialization conflict as development achieved by industrial investment increase social problems and environment pollution. Circumvention of lax legislation in developing countries by the developed countries enables them to establish industrial subsidiaries where they are able to evade industrial countries stringent checks and controls (Global 2000, 1980).
The status of population growth in the developing countries coupled with limited environmental awareness are making developing countries practice an alarming trend of destructive natural resources exploitation (PECCEI, 1981).
Passing of appropriate laws and their enforcement seem to be the only way to contain the high and alarming concentration of environmental pollutants. Biological diversity management in a manner construed to be sustainable is the present challenge of the recent times (Hawk-sworth and Ritchie 1993).
Interaction between the biological diversity, climate and the landscape produces ecosystems. Human activities and integration impacts the ecosystems in a number of ways such as environmental degradation, ecological fragmentation and exotic biota introduction (Finnamore 1992).
The Essay on Environmental Science Human Population
Environmental Science - Human Population It is a truth that many people, in developing countries, starve on daily basis, while being unable to break the vicious circle of poverty. But it just never occurs to the whining liberals, in our government, who come up with different plans of how to provide these people with food, that the constant starvation and high children's mortality in Africa, for ...
In some ecosystems exotic biota play a significant role in the provision of food thus acting as a supporting platform for human growth and development. As a result the primary aim of biodiversity management should be the attainment of these four goals. First is the maintenance of viable populations of all native species seconded by protection of representative examples comprising of all native ecosystem types across their natural range of variation. Thirdly is the maintenance of ecological and evolutionary processes such as nutrient cycles.
Fourthly is the management of landscapes and species responsiveness both in the short term and in the long run. Once an ecosystem is properly managed resource use is done in a sustainable manner, healthy regional economies are developed and human population is maintained through sustainable population control (Campbell, 2005).
Ecosystem dynamics are driven by the invertebrates which includes arthropod fauna, microflora, and microfauna. Arthropods form a considerable percentage of the global diversity.
Information derived from arthropods is rich in crucial data which can be used in ecosystem management demonstrating the importance of environmental monitoring (Biological Survey of Canada, 1996).
To get advance warning of an ecosystem change arthropods are used as indicator species where they provide required data. The quick reactions of some species of arthropods make them best suited for acting as bioindicators. Among the diversified environmental functions of arthropods is the indication of habitat disturbance, pollution and climate change (Hawk-sworth and Ritchie 1993).
Arthropods provide crucial information on environmental quality when used in aquatic ecosystems. As stated earlier arthropods constitute a diversified ecological choice resulting in the collection of a wide range of necessary data after the designing of appropriate assessment programs (Biological Survey of Canada, 1996).
Using bioindicators to monitor a freshwater ecosystem Freshwater is a habitat for different species of sea creatures such as fish and a variety of arthropods and plants (Ghosh and Pattnaik 2005).
The Research paper on Marine and Terrestrial Ecosystem in Nukapu Island
A case study of the Islet Terrestrial and Marine Ecosystem. This essay is on the case study of the Terrestrial and the Marine Ecosystem of Nukapu Island. The island is one of the fourteen Islands in Temotu Province the easternmost part of the Solomon Islands, approximately about 1mile in length with a narrow width along with a huge extensive coral reef (fig. 1)and is located at the latitude ...
Their survivability depends on the quality of water they live in.
Some accumulate chemicals in their bodies which affect the physiological performances. Others move to places where water quality is better while others die due to pollution and therefore become extinct (United States Environmental Protection Agency, 1998).
Both plants and living organisms can be used to monitor the effects of human activities on freshwater ecosystems (Grimsditch, 2005).
Pollutants monitoring constitute one of the pillars of environmental science the other being analytics. These tools provide reliable information on the state of the environment and the changes taking place.
Organism use in the registration and evaluation of the environment is founded on the ecological theorem between environmental factors and species requirements. Bioindicators Arndt et al (1987) defined bioindicators as organisms or communities of organisms that react to pollution in the environment by altering their vital functions or by the accumulation of toxins (Underwood 2000).
Bioindicators that provide information on conditions of an ecosystem are referred to as pointer organisms. Information provided by pointer organisms range from pH value data to metal concentration in the soil constitution or water quality.
The pointer organisms also provide information on reaction by some plant species to environment changes which range from plant death to plant multiplication. To identify changes in an ecosystem for comprehensive environmental inventories compilation, data need to be collected in a long term repeated manner from pointer organisms. In toxicological laboratory tests and water analysis test organisms are used due to their high standardization which makes it easy to detect immediate risks for human beings.
Apart from being used to test environmental chemicals, test organisms are used for monitoring and controlling air pollution by testing their phyto-toxicity in the laboratory. To qualitatively and quantitatively monitor pollutant levels in the environment and their effect on the ecology, monitor organisms which constitutes a variety of living organisms are used. Passive monitoring is performed with organisms already present in an ecosystem while active monitoring happens when organisms are introduced to an ecosystem in a standardized form.
The Term Paper on Heavy Metals Pollution in Water
HEAVY METALS POLLUTION IN WATER Generally the water pollution is described as the presence in water of enough harmful or objectionable material to damage the water's quality. Water pollution has many sources and characteristics. Humans and other organisms produce bodily wastes which enter rivers, lakes, oceans and other surface waters; Industry is creating new chemicals each year, all of which ...
On establishing of adequate and specific benchmarks, injury observed and chemical analyses performed allow conclusions to be drawn on quantitative levels of pollutants. Air pollution monitoring, a component in water pollution, by monitor organisms provide data on a variety of biological levels as it relates to attributes suitability in each case and observation on organism response to exposure to a pollutant can be made and measured in physiological terms or biochemical terms.
Large numbers of plant species such as coral reefs are now utilized for biological monitoring approaches where visible symptoms of injury to certain organ serve as criteria. Their use is due to meeting of a number of demands made of biological factors. These factors are identified as easy to handle and care for, can be standardized, their conditions of response are well known, and are cost effective. In addition their responses are easy to evaluate, their effects of pollution quantifiable and outright, genetic uniformity can be achieved through them and their responses can be statistically evaluated.
In observation of naturally occurring plant species investigation of plant species makeup in a community and their resulting changes brought about by the atmospheric pollution opens up new environmental monitoring possibilities (Kutscheraritter et al. , 1982).
Beyeler and Dale (2001, p. 6) stated that the key to overall success in any monitoring programme is selection of effective indicators. Selection of robust indicators enables gauging the health of different aspects such as environmental, social, and economic activity and this allows impact management (Linton and Warner 2003, p.
262).
The use of bioindicators has taken root due to its cost effectiveness and the reduction of complex stress signals to simple measurable outputs. Beyeler and Dale (2001, p. 3) explained that indicator species are able to provide data indicative of a larger functional group and can be used in the assessment of environmental condition providing early warning signs for environmental changes and causal diagnosis of an environmental problem. Indicator use depends on cost, purpose and feasibility for efficient data collection. Criteria for selecting bioindicator organisms
The Essay on Water Pollution 16
Water Pollution People keep on throwing trash and industrial wastes into our clean water. If this continues, the quality of our water will deteriorate, and without it everything dies, including us. Water pollution is destroying our world, but fortunately we can count on special treatments for this kind of problem. What is water pollution? "It is the contamination of water by foreign matter such as ...
In order to satisfy representativeness of the ecosystem resident animals and correct plants should be used as bioindicators. Beyeler and Dale (2001) stipulated that indicators should be easily measurable, stress sensitive, should respond to stress in a predictable manner with little deviation, anticipatory, predict changes able to be dealt by the management action and should be integrative in that they should be selected for numerous important environmental variables and allow comparison to perfect habitats (Miller et al 2005, Underwood, 2000).
In addition the selected species should have a wide geographical representation with ease in identification and sampling. Moreover the selected organisms should give the possibility of sufficient amount of materials collection for the intended study. Additionally the selected organisms and or species should have a relatively high resistance to pollutants such as heavy metals or organic compounds. Beyeler and Dale (2001) continued and stated that the selected organisms for use as bioindicators should be easy to transfer and they should easily adapt to new habitat having no difficulty in transportation to the laboratory for analysis.
Similarly the selected bioindicators should have a stable population to allow for multiple sampling over an extended period of time. Accordingly there should be a reasonable correlation between pollution of the water component and the bioindicator selected (Namiesnik 2001).
Beyeler and Dale (2001) stated that measurement of the indicator should be non-intrusive and able to produce qualitative results. Although single species as indicator may be misleading, multiple species bioindicator and community structural changes monitoring help overcome this problem due to their wide variable monitoring.
Pollution and fresh water ecosystem Pollution being introduction of anything that alters the physical, chemical, biological or radiological integrity of water great care is to be taken to lessen effects of human activity and the related diseases. Chemicals from factories and sewer wastes are changing the nature of fresh water ecosystems in a significant manner (Grimsditch, 2005).
The Essay on Importance Of Biological Aspects In The Human Species Adaptation
Importance of Biological Aspects in the Human Species Adaptation One of the biggest unknowns that humanity has been wondering over the years was first of all, the origin and evolution of human kind, and second how we have been able to survive through so many changes that have existed for millions of years? That will be the topic will be discussed in this essay, an explanation of how the human ...
These changes are resulting into elimination of ecological species especially those sensitive to pollution and fish species are reduced and thereby reduced fish harvests (O’Connor, 2002).
Continued pollution by human activities such as pesticide use, factory effluents, among others diminishes freshwater ecosystem living organisms by altering their biological elements (Miller et al 2005).
Additionally sedimentation from coastal development and pollution from the direction of waste waters from these developments to water courses are problems affecting fresh water ecosystems such as coral reefs in Fiji (Barnard et al. 2003).
As a result biological monitors are essential to protect these important biological resources as they will provide relevant information.
Overgrazing alters the plant cover and increases erosion thereby increasing sedimentation which affects the quality and quantity of water flowing to the rivers and the oceans. Moreover over-harvesting of sea species for sport and commercial purposes such as food and curio sales do as much harm as chemicals that flow from industries and factories to the fresh water ecosystem (Grimsditch, 2005).
According to O’Connor (2002) bivalve shellfish have been used as bioindicators for heavy metals and pesticides in aquatic contamination.
Moreover shell fish has been identified as a good bioindicator of aquatic contamination with faecal origin full of bacteria, viruses and parasites (Fayer et al. , 1998, Freire-Santos et al. , 2000, Pommepuy et al. , 2004).
Biological monitoring Measurement of changes in organisms and or the ecosystems brought about by environmental influences of anthropogenic origin is referred to as biological monitoring. Biological monitoring is performed using monitor organisms in a spatial and differentiated manner having established benchmarks. Biological monitoring uses response oriented monitoring procedures as favored by attributes they possess.
The Essay on Human Body Water Food Cell
The human body consists of massive amounts of different tissues and oranges, all doing different things. It's inevitable that these tissues need a large amount of energy to maintain health and to stay productive. When the body encounters a famine, it reacts to the lack of food by many different starvation endorse tactics. When the body enters into a lack of water, there is very little it can do ...
This attributes constitutes response indication, cross-sensitivity that strengthens the overall effect instead of interfering with accuracy. In addition the unification of a diversified number of parameters including the different types of pollution in the air and water constitutes favorable attributes. Detection of chronic pollution levels by bioindicators enables accurate measurement and analysis. Bioindicators provide useful data that for the attainment of water quality control goal which is containment of the effect of pollution and biodiversity protection through effective biodiversity management.
Biological monitoring takes two approaches with the first one aiming at identification of environmental impact of identified pollutant sources while the second approach serve the function of describing the importance of given bioindicators. Active monitoring using bioindicators help in the collection of evidence against environmental polluters and the testing of the environmental compatibility of technical facilities in use. Biological indicators should be sedentary within their habitats enabling them reflect quality of water and other ecosystems changes by pollution (Ghosh and Pattnaik 2005, Miller et al 2005).
Collection of information using passive or active indicators is done with changes inside the organisms being monitored. Assessment and Analysis Biological monitoring, assessment and evaluation play an important role in the redirection of effort towards formulating programs aimed at restoring and maintaining the chemical, physical, and biological integrity of the water resources. The first step toward effective biological monitoring and assessment is to understand that the goal of the environmental monitoring is to measure and evaluate the consequences of human actions on biological systems in the environment (Ghosh and Pattnaik 2005).
The relevant measurement endpoint for biological monitoring is change in biological condition. Where change is detected in the endpoint, comparison of the change with a minimally disturbed baseline condition is done, causes for the changes are identified, and communication of the findings to policymakers and citizens is done to meet the expectations of the biological monitoring programs (United States Environmental Protection Agency, 1998).
This outline must be kept in mind to help keep biological monitoring programs on track. Human activities effects on the ecosystems are positive and negative (Ghosh and Pattnaik 2005).
Therefore as biological monitoring aims at measuring the biological condition in the absence of human beings to find out the cause of conditions moving away from integrity the human interference should be reduced significantly to enable the collection of accurate results. Hence managers performing biological monitoring must evaluate present information, information on expected biology, present geophysical setting information, expected geophysical setting information and information on human activities likely to alter biological and geophysical setting and plan the monitoring in a prudent manner.
Assessment of the collected information from bioindicators is crucial and should be done using multivariate and multimetric indexes to get a comprehensive outlook entailing the pattern and the impact of human activities on fresh water ecosystem (Karr and Chu, 1997, Grimsditch, 2005).
To make multi-metric biological indexes effective the following activities should be undertaken. First, the environments should be classified in homogenous sets within or across eco-regions. Second, measurable attributes should be selected that provide reliable and relevant signals about the human activities’ biological effects.
Thirdly sampling protocols and designs should be developed and they should ensure that biological attributes selected are measured accurately and precisely. Fourthly analytical procedures to extract and understand relevant patterns in the data should be devised. Protecting the biological resources requires correct identification and prediction of human action effects on the biological systems distinguishing between natural and human induced variability (Ghosh and Pattnaik 2005).
As a result therefore measures are to be collected from reference sites to give information on the natural state of things in undisturbed circumstances. An all encompassing measure should be sought to get information on similar environments with disturbance and with varying degrees of severity. As diverse human activities interact, no one human activity can be credited as the causal activity of ecosystem changes therefore identification of a variety of activities should be aimed at for meaningful analysis and recommendations.
Moreover the diverse decisions to be made by different players regarding an ecological system require multiple level of information especially when this is considered in the light of the complexity of ecosystems. Measuring variable therefore has to done in an extensive manner to enable users of the information make well informed decisions having overall consideration of an ecosystem (Karr and Chu 1997).
For instance to detect Cryptosporidium and Giardia spp. in bivalve shellfish, DNA amplification by PCR and direct Immuno-Fluorescent Antibody (DFA) assays were used (Graczyk et al., 1998, Gomez-Couso et al. , 2003).
On the other hand testing freshwater clams (Corbicula fluminea) to detect faecal pathogens in freshwater ecosystems because clams filter large volumes of water and they survive well in polluted aquatic environments is considered a very useful approach. In addition freshwater clams are easily collected and transported to the laboratory for analysis (McMahon and Bogan, 2001) meeting the criteria for selecting bioindicators which elaborates that bioindicators should be easy to transport to the laboratory for analysis.
To the practical aspect of testing clams as indicators of water quality, they are of great interest because both humans and animals harvest them as a food source indicating that bivalves’ shellfish might expose consumers to pathogens when eaten raw. Once data is collected and analyzed the results should be communicated to the public and policy makers to ensure that all concerned contribute to the formulation and implementation of environmental policies for sustainable development. Advantages
Proper assessment of biological monitoring leads to the application of better evaluation approaches namely multivariate statistical analysis and multi-metric indexes. Multivariate statistical analysis facilitates the detection of pattern while multi-metric indexes were designed to provide strong signals about the impact of humans. Using this information, factors likely to cause degradation are detected and action prescribed. Additionally multi-metric indexes are able to strengthen earlier monitoring approaches by utilizing a wide spectrum of biological attributes to respond to human influence to varying degrees.
Multi-metric indexes apart from the wider scope consideration reflect specific and predictable responses of organisms to landscape changes. In addition given that biological indicators are sedentary within their habitats this enables them reflect quality of water and other ecosystems changes by pollution over an extended period of time (United States Environmental Protection Agency, 1998).
Combining approaches is advantageous in that tracking complex systems requires a measure integrating multiple factors which is crucial in overall information gathering.
Furthermore metrics are selected to yield relevant biological information at reasonable cost. Multimetric indexes are built from proven metrics and a scoring system thus their ease in assessment to get accurate results is notable. The statistical properties of multimetric indexes are known. Multimetric indexes reflect biological responses to human activities in diverse environments. Multimetric indexes are biologically meaningful and their set of rules can work in environments other than streams and freshwater bodies (Karr and Chu 1997).
Disadvantages
Biological monitoring requires massive instrument investment for evaluation and analysis of the information collected by the bioindicators. In addition there is lack of the required expertise to perform accurate and reliable monitoring and analysis of information gathered. Using indicators for large regions and large freshwater bodies can be ineffective because each monitoring problem requires individual treatment and as identified above there is no one bioindicator species that will suit all programmes for effective environmental biomonitoring (Linton & Warner, 2003).
In addition bioindicator dependent monitoring programmes are plagued with numerous problems as identified by Beyeler and Dale (2001) namely the reliance on insufficient indicators, unclear management objectives and the difficulty in application of bioindicators scientifically. Reliance on insufficient indicators lacks a true reflection of the whole ecosystem and thus poor management while unclear management objectives lead to wrong variable monitoring and consequently ineffective indicators selection. Conclusion and recommendations
Diversity management for future generation use is essential in the present growing population and resource use. Realistic information makes it possible for ecosystems to be exploited in a sustainable manner. Information gathering for effective biodiversity management is complimented by the use of arthropods together with other organisms as bioindicators. Information gathered from arthropods provides a higher resolution for investment apart from incurring less cost as compared to vertebrate and vascular plants use.
Water resources are very vital in the development of life and quality water resources are as a result of properly formulated policies informed by accurate and reliable information collected through bioindicators. The sensitivity of environmental protection by the general public has resulted in political parties’ changes and emergence of new ones as each try to persuade and dissuade others to protect the environment and stop degrading the environment through environmentally polluting activities. Decisions on protecting the environment have been done thus placing ecological importance at a platform of great importance.
It is worth noting that economic needs and ecological goals require harmonization for the attainment of sustainable development. Support for effective bioindicator/ biomonitoring require participation by all key players in the maintenance of sustainable development. Training to raise the expertise of persons undertaking biomonitoring is highly recommended. Equipments required for analysis of information collected are expensive and therefore government funding and private-public partnership should be sought to acquire the equipments.
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