These include:. Introduced species threaten the existence of native species through competition for food and space, predation and the introduction of exotic parasites and diseases. For example, the swordtail Xiphophorus helleri and gambusia Gambusia holbrooki are two introduced species that appear to depress native fish populations through the occupation of space and competition for food.
Introduced aquatic plants include the water-fern salvinia Salvinia molesta and water hyacinth Eichhornia crassipes. These are two of the world's most successful floating aquatic weeds.
For example, three water hyacinth plants may produce new plants in 50 days. These plants may colonise waterways to the extent of restricting the movement of boats, blocking pump suctions and irrigation structures and significantly altering water quality by reducing light penetration and dissolved oxygen levels beneath the water surface. Fish moving along waterways and up through fishways are often unwilling to enter into water covered with water hyacinth mats, due to the low oxygen levels and low light levels.
Salvinia was first recorded for Queensland in from Bulimba Creek, Brisbane. A South American weevil Cyrtobagous salviniae was released in It now controls salvinia over most of its range in Australia. Water hyacinth was first recorded from the Botanical Gardens in Brisbane. Successful control of water hyacinth has been achieved in parts of Australia with a South American weevil Neochetina eichhorniae , while a second species N.
Central Queensland and the Gulf of Carpentaria, like the rest of Northern Australia, experience distinct wet and dry seasons each year. During the dry season native pastures provide fewer nutrients for cattle. As a strategy to provide green forage for cattle during the dry season, ponded pastures of non-native water-tolerant grasses such as para grass Brachiaria mutica and aleman Echinochloa polystachya are grown in artificially ponded situations.
This invasive grass smothers waterside vegetation such as native ferns and brush. Para grass also burns much hotter than native vegetation often resulting in hot fires that kill the native riparian vegetation including trees. Ponded pastures are generally created by building low walls or banks at selected sites to trap available water from natural run-off during the wet season.
Water for the pond is also obtained by diversion from adjacent water courses or from water-harvesting during flood flows in major streams. More than 26, ha of ponded pasture has been established along the central Queensland coast. Ponded pasture systems benefit many grazing industries especially beef and dairy cattle.
Ponded pasture structures are potentially detrimental to aquatic species. Levee banks for ponded pasture prevent access by fish to and from floodplains and wetlands, for example barramundi, which spawn in inshore coastal waters in the mouths of estuaries.
Barramundi juveniles use coastal swamps, marine plains and flood plains as nursery areas. The older juveniles use tidal and freshwater reaches of coastal waterways during their growth. Ponded pastures may also result in fish kills. The ponded pastures may initially create habitat for fish but as this habitat dries out and water quality drops then fish may be trapped and die. Last updated: 01 Nov Mobile Search. Mobile Menu. Our organisation About us. Our Board of Management.
Our Minister. Topics: Growing for Queensland. Employment and jobs. Right to information. Topics: Publication scheme Disclosure log. Topics: eResearch Archive Research stations and facilities Biological collections. Data Farm. Annual report. Strategic plan. Service delivery statements. Information security attestation.
Disability service plan — Fraud, corruption and misconduct control policy. Integrity framework. Economic recovery—support for Queensland producers announced. Multicultural action plan. Open data. Recharges a drinking water source, such as a well head or source protection area. Reduces levels of contaminants in surface waters which recharge underlying or adjacent groundwaters.
Contributes to the flows of Class A surface waters. Enhances or protects water quality through chemical action, by the removal of nutrients, by the retention or removal of sediments or organic matter, or by moderating the adverse water quality effects of soil erosion or stormwater runoff. Contributes to the protection or improvement of water quality of any impaired water.
Is adjacent to surface waters, especially impaired waters. Menu Vermont Official State Website. Wetland Functions and Values: Surface and Ground Water Protection Many pollutants are washed by rainfall from urban and agricultural lands and are carried overland to water bodies.
In determining whether a wetland is significant for the Surface and Ground Water Protection function,the Secretary or Panel shall, at a minimum, consider the extent to which it: a. Links of Interest Wetlands and Water Quality : produced by Purdue University Cooperative Extension Service, this publication reviews the importance of wetlands to water quality, as well as some other functions.
Clean Water Initiative : see what Vermont is doing with wetlands to help clean up the water in Lake Champlain. Pollution enters the water table through pesticides, sediment, sewage, fertilizers and many other forms. Once a wetland is polluted, it's difficult to clean it up. The best way to keep wetlands clean is to protect them from pollution in the first place, by ensuring a contaminant-free water supply.
Global warming is also a threat to wetlands. A study by the Pew Center on Global Climate Change found that as air temperatures rise, so do water temperatures. The algae bloom known as red tide releases toxins, which have killed thousands of fish.
Eating affected shellfish can expose humans to these toxins. Breathing the air near a red tide can also cause respiratory issues in some people [source: CDC ].
Also, many fish rely on cooler water to survive and can die out when smaller lakes or ponds warm up. Elevated temperatures also lead to reduced precipitation, which reduces the amount of runoff provided to wetlands [source: Pew Center]. So what can be done to save the wetlands? Keep reading to learn what the U. Clean Water Act and other private organizations are doing to protect wetlands.
Wetlands don't just nourish wildlife, they nourish storytellers' imaginations. For example, in the state of New Jersey, the "Jersey Devil" legend frightens children with its description of a creature born with a tail, hooves and wings that lives in the wetlands by day and destroys crops and livestock by night [source: State of NJ ]. Wetlands also serve as excellent backdrops for creepy movies and books.
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