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Environmental Issues
The World As It Is
Learning from Observing
Learning About The Food Web
Everyone plays a specific role in the food chain of life. You might be a human thinking they are king of the hill or you might be a bacterium under the feet. You are very important to the survival of the system no matter what role you play.
As you study more about ecosystems and cycles in life, you will see the terms food chains and food webs. They describe the same series of events that happen when one organism consumes another to survive. Food web is a more accurate term since every organism is involved with several other organisms. Cows might be food for humans, bacteria, or flies. Each of those flies might be connected to frogs, microbes, or spiders. There are dozens of connections for every organism. When you draw all of those connecting lines, you get a web-like shape.
The Producers
Producers are the beginning of a simple food chain. Producers are plants and vegetables. Plants are at the beginning of every food chain that involves the Sun. All energy comes from the Sun and plants are the ones who make food with that energy. They use the process of photosynthesis. Plants also make loads of other nutrients for other organisms to eat.
There are also photosynthetic protists that start food chains. You might find them floating on the surface of the ocean acting as food for small unicellular animals.
The Consumers
Consumers are the next link in a food chain. There are three levels of consumers. The levels start with the organisms that eat plants. Scientists named this first group of organisms the primary consumers. They are also called herbivores. They are the plant eaters of the chain. It might be a squirrel or it might be an elk. It will be out there eating plants and fruits. It will not eat animals.
Secondary consumers eat the primary consumers. A mouse might be a primary consumer and a cat might be the secondary. Secondary consumers are also called carnivores. Carnivore means "meat eater."
In some ecosystems, there is a third level of consumer called the "tertiary consumer" (that means third level). These are consumers that eat the secondary and primary consumers. A tertiary consumer could be a wolf that eats the cat and the mouse.
There are also consumers called omnivores. Omnivores can either be secondary or tertiary consumers. Humans and bears are considered omnivores: we eat meat, plants, and just about anything.
The Decomposers
The last links in the chain are the decomposers. If you die, they eat you. If you poop, they eat that. If you lose a leaf, they eat it. Whenever something that was alive dies, the decomposers get it. Decomposers break down nutrients in the dead "stuff" and return it to the soil. The producers can then use the nutrients and elements once it's in the soil. The decomposers complete the system, returning essential molecules to the producers.
Learning About The Native Vegetation & Habitat
Why is native vegetation important?
Native vegetation is one of our most precious natural assets. It helps provide a healthy environment for humans and all life. It provides an essential habitat for native animals and underpins our natural ecosystems. Native vegetation plays an important role in stabilising the soil, making it less vulnerable to wind and water erosion. It also reduces the impact of climate change by absorbing greenhouse gases such as carbon dioxide from the atmosphere. Unfortunately, many of these benefits are 'hidden' and most are often taken for granted. Native vegetation is also important in preventing dry-land salinity through its influence on groundwater levels. It also provides valuable shelter and windbreaks for stock and crops.
How is native vegetation threatened?
Native vegetation is rapidly vanishing due to it being cleared to make way for agriculture, housing and other land uses. Other pressures that have affected the condition of native vegetation include:
- over-grazing and trampling by sheep, cattle, rabbits, goats and camels
- the invasion by weeds
- fire
- plant diseases
- firewood collection
- increased soil salinity and rising groundwater
- altered water flows in rivers and streams
- and pollution.
What happens when we clear native vegetation?
The environmental effects of the clearance of native vegetation are significant and include:
- loss of habitat for native plants and animals
- potential loss of plant species and reductions in genetic diversity
- fragmentation of habitats, reductions in population sizes of plant and animal species with an increased potential for local extinctions associated with single events, such as bushfires
- increased salinity problems associated with the removal of deep-rooted perennial plants
- increased vulnerability to weed invasion
- de-stabilisation of soil, leading to wind and water erosion
- impact on the health of catchments
- changes in water flow patterns and hydrology
increased greenhouse implications (the removal of vegetation inhibits the absorption of carbon dioxide from the atmosphere).
Riparian zones: what are they and why are they important?
The riparian zone is land which is next to a water-body, like a river or lake, and is influenced by that water-body. Riparian zones generally have a great diversity of animals and plants compared to adjoining habitats. The vegetation found in riparian zones ranges from aquatic plants to mature trees and understorey vegetation. Riparian vegetation is very important for providing habitat for animals, stabilising creek beds, preventing erosion, and protecting water quality. Riparian zones are threatened by loss of native vegetation, weed invasion, inappropriate development and unrestricted stock access.
To help slow down or reduce the spread of invasive plants, here are some steps you can take:
- become informed.
- practice prevention.
- instill control methods.
- deal with the waste.
Learning About The Water Cycle
The Earth's water is always in circulation. It has been recycled for the last 3 billion years. This process is called the water cycle.
The cycle starts when the sun's heat provides energy to evaporate water from the surface. Then, winds lift the water vapor from the ocean over the lands into the atmosphere. The water vapor condenses to form clouds, and when the conditions are just right, the clouds release water as rain or snow. About 80% of the rain falls in the oceans, but the rest falls onto land. Rivers and streams collect water from the ground and return it to the ocean so the whole cycle can start all over again. The water cycle never ends because the salty ocean water constantly supplies fresh water to the continents.
Here is a quick summary of the water cycle. The links in this paragraph go to the detailed Web pages in our Web site for each topic. A shorter summary of each topic can be found further down in this page, though.
The water cycle has no starting point. But, we'll begin in the oceans, since that is where most of Earth's water exists. The sun, which drives the water cycle, heats water in the oceans. Some of it evaporates as vapor into the air. Ice and snow can sublimate directly into water vapor. Rising air currents take the vapor up into the atmosphere, along with water from evapotranspiration, which is water transpired from plants and evaporated from the soil. The vapor rises into the air where cooler temperatures cause it to condense into clouds. Air currents move clouds around the globe, cloud particles collide, grow, and fall out of the sky as precipitation. Some precipitation falls as snow and can accumulate as ice caps and glaciers, which can store frozen water for thousands of years. Snowpacks in warmer climates often thaw and melt when spring arrives, and the melted water flows overland as snowmelt. Most precipitation falls back into the oceans or onto land, where, due to gravity, the precipitation flows over the ground as surface runoff. A portion of runoff enters rivers in valleys in the landscape, with streamflow moving water towards the oceans. Runoff, and ground-water seepage, accumulate and are stored as freshwater in lakes. Not all runoff flows into rivers, though. Much of it soaks into the ground as infiltration. Some water infiltrates deep into the ground and replenishes aquifers (saturated subsurface rock), which store huge amounts of freshwater for long periods of time. Some infiltration stays close to the land surface and can seep back into surface-water bodies (and the ocean) as ground-water discharge, and some ground water finds openings in the land surface and emerges as freshwater springs. Over time, though, all of this water keeps moving, some to reenter the ocean, where the water cycle "ends".
Notation: U.S.A. Clean Water Act
From: The Poughkeepsie Journal, May 28, 2006
OUR Environment
The first national assessment of the biologic health of small streams in the United States, the Wadeable Streams Assessment, was released this month. The report will be used in future assessments to evaluate changes in conditions and to provide insights into the effectiveness of actions taken to enforce the Clean Water Act, which aims to "restore and maintain the chemical, physical, and biological integrity of the Nation's waters."
97,913 Miles of streams in the Northern Appalachian region that the Environmental Protection Agency assessed at 85 sites in 2004. Stream health was measured based on the presence of aquatic life like insects and crustaceans. The "eco-region" includes New England, New York and parts of Pennsylvania and Ohio.
45%- Percentage of streams stressed by nitrogen or phosphorus, the top causes of degradation. Other major factors included polluted stream sediments and loss of stream-bank cover.
23%- Of the region's streams sampled that retained the expected contingent of aquatic life. Half of streams had lost at least 10percent of life, and 19 percent of streams had lost half of life.
52%- Percentage of poor quality streams in the Northern Appalachian region-- the largest proportion of poor-quality streams of any region in the nation. The analysis, however, did not include many of pristine headwater streams as it did in other regions.
40.6 million --Population of people in the region, about 14 percent of the nation.
Components of the water cycle ~ The U.S. Geological Survey (USGS) has identified 15 components of the water cycle which are linked: read on.
Climate Change ~ What You Can Do At Home
Making a few small changes in your home and yard can lead to big reductions of greenhouse gas emissions, increase the nation's energy independence and save money. Explore below the nine simple steps you can take around the house and yard to reduce greenhouse gas emissions:
- Change 5 lights
Change a light and you help change the world. Replace the conventional bulbs in your 5 most frequently used light fixtures with bulbs that have the ENERGY STAR label and you will help the environment while saving money on energy bills. If every household took this one simple action, we would prevent more than 1 trillion pounds of greenhouse gas emissions.
- Look for ENERGY STAR labeled products
When buying new products, such as appliances for your home, get the features and performance you want AND help reduce greenhouse gas emissions and air pollution. Look for ENERGY STAR qualified products in more than 40 product categories including lighting, home electronics, heating and cooling equipment and appliances.
- Heat and cool smartly
Simple steps like cleaning air filters regularly and having your heating and cooling equipment tuned annually by a licensed contractor can save energy and increase comfort at home, and at the same time reduce greenhouse gas emissions. When it's time to replace your old equipment, choose a high efficiency model, and make sure it is properly sized and installed.
- Seal up your home with better insulation and duct-work
Close up any visible cracks and gaps in your house, install adequate insulation, check that ducts are sealed and choose ENERGY STAR qualified windows when replacing old windows. Not sure where the cracks and gaps are? A home energy auditor can also help to identify areas with poor insulation and evaluate the energy efficiency of your home. By taking these steps, you can eliminate drafts, keep your home more comfortable year round, save energy that would otherwise be wasted, and reduce greenhouse gas emissions.
- Use green power
Green power is environmentally friendly electricity that is generated from renewable energy sources such as wind and the sun. There are two ways to use green power: you can buy green power or you can modify your house to generate your own green power. Buying green power is easy, it offers a number of environmental and economic benefits over conventional electricity, including lower greenhouse gas emissions, and it helps increase clean energy supply. If you are interested, there are a number of steps you can take to create a greener home including installing solar panels and researching incentives for renewable energy.
- Reduce, Reuse, and Recycle
If there is a recycling program in your community, recycle your newspapers, beverage containers, paper and other goods. Use products in containers that can be recycled and items that can be repaired or reused. In addition, support recycling markets by buying products made from recycled materials. Reducing, reusing, and recycling in your home helps conserve energy and reduces pollution and greenhouse gases from resource extraction, manufacturing, and disposal.
- Be green in your yard
Use a push mower which, unlike a gas or electric mower, consumes no fossil fuels and emits no greenhouse gases. If you do use a power mower, make sure it is a mulching mower to reduce grass clippings. Composting your food and yard waste reduces the amount of garbage that you send to landfills and reduces greenhouse gas emissions. Smart landscaping can save energy, save you money and reduce your household’s greenhouse gas emissions.
- Use water efficiently
Everyone can save water through simple actions. Municipal water systems require a lot of energy to purify and distribute water to households, and saving water, especially hot water, can lower greenhouse gas emissions. Do not let the water run while shaving or brushing teeth. Do not use your toilet as a waste basket for toiletry items - water is wasted with each flush. AND, did you know a leaky toilet can waste 200 gallons of water per day? Repair all toilet and faucet leaks right away.
- Spread The Word
Tell family and friends that energy efficiency is good for their homes and good for the environment because it lowers greenhouse gas emissions and air pollution. Tell 5 people and together we can help our homes help us all.
Did You Know? The water you save every year by purchasing a new ENERGY STAR qualified clothes washer instead of a new non-qualified model is enough to do 300 loads of laundry.
"An Inconvenient Truth by Al Gore" ... This is a must-see; an absolutely terrifying "wake-up call" of what is going on in the World today and into the future.
Here is something to be cherished ~ a slideshow entitled Our Planet Earth. Enjoy and remember what we should be protecting. Instructions for slideshow: simply click on the screen and it will move to next slide. When done, right click and press "end show". [Please be patient for the download.]
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