Other losses occur cumulatively and unobtrusively through lack of knowledge or careless resource management. Maintenance and enhancement of economically valuable aquatic ecosystem functions— especially floodwater storage and conveyance, pollution control, ground water recharge, and fisheries and wildlife support— have all too often been largely ignored in aquatic resource management. Even when management has been directed to these ends, it has often been fragmentary in its emphasis on lakes, rivers and streams, or wetlands in isolation from their regional watershed contexts— despite clear hydrological and ecological linkages.
Restoration of Aquatic Systems - CRC Press Book
Contemporary restoration work is often too narrow in emphasis, focusing in lakes, for example, on correcting nutrient. Similarly, stream restoration efforts often concentrate on fisheries without regard for the wildlife values of riparian zone vegetation. Wetland restoration efforts often focus on revegetation while paying little attention to deep-water zones. The purpose of this report is to suggest and analyze strategies for repairing past and ongoing damage to aquatic ecosystems from all types of anthropogenic activities.
The loss or alteration of a large percentage of lakes, rivers, streams, and wetlands and of their associated vital ecological functions has a major effect both on the quality of life and on carrying capacities for human societies. These ecosystems provide a variety of ecological services of value to society.
To ensure their viability for sustained, long-term use, freshwater ecosystems require not only protection from pollutants but also restoration and informed management. The thesis of this report is that restoring altered, damaged, or destroyed lakes, rivers, and wetlands is a high-priority task at least as urgent as protecting water quality through abatement of pollution from point and nonpoint sources. Indeed these two activities are not dissociated, but rather are part of a continuum that includes both protection from pollution, and restoration and management.
Restoration is essential if per capita ecosystem service levels are to remain constant while the global human population increases. This report describes the status and functions of surface water ecosystems; the effectiveness of aquatic restoration efforts; the technology associated with those efforts; and the kinds of research, policy, management, and institutional changes required for successful restoration Even if a major national effort is made to restore aquatic ecosystems, their protection and management will require continued advances in point and nonpoint pollution abatement.
In short, the first objective should be to ensure no net loss of the quality of aquatic ecosystems, followed by efforts to increase the number of robust, self-maintaining aquatic ecosystems. Management of aquatic ecosystems will require intensive monitoring, as well as increased interaction and cooperation among national agencies concerned with air, water, wildlife, soil, agriculture, forestry, and urban planning and development.
Restoration is increasingly becoming an integral part of a national effort to improve water quality and the ecology of aquatic ecosystems. A planning session was organized in the summer of to see if an NRC study of aquatic restoration efforts was appropriate. The planning committee decided that the science developing to support the emerging techniques of aquatic ecosystem restoration could benefit from an NRC assessment and report that would bring together significant and useful information on aquatic restoration efforts.
The committee was requested to identify restoration projects and attempt to ascertain if they had succeeded or failed. Scientific, technological, political, and regulatory aspects were to be considered, as well as other factors that aid or hinder restoration efforts. The committee was composed of 15 restoration experts from the fields of limnology, geomorphology, surface water hydrology, aquatic. During the study the committee visited several restoration sites to determine firsthand how restoration efforts are accomplished. Writing assignments were made to several subcommittees concentrating on restoration of rivers, lakes, wetlands, and large integrated systems.
Another subgroup concentrated on the development of a national aquatic ecosystem restoration strategy and the changes in policy and institutions necessary to begin this process. As used in this report, the term restoration see Box 1. Restoration is different from habitat creation, reclamation, and rehabilitation— it is a holistic process not achieved through the isolated manipulation of individual elements. The holistic nature of restoration, including the reintroduction of animals, needs to be emphasized.
The installation of a few grasses and forbs does not constitute restoration. The long-term maintenance of biodiversity depends on the survival of appropriate plant assemblages, which may require, for example, grazing by muskrat and beaver. Without critical faunal elements, an ecosystem may not survive long. In this report, restoration is defined as the return of an ecosystem to a close approximation of its condition prior to disturbance.
In restoration, ecological damage to the resource is repaired. Both the structure and the functions of the ecosystem are recreated. Merely recreating the form without the functions, or the functions in an artificial configuration bearing little resemblance to a natural resource, does not constitute restoration.
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The goal is to emulate a natural, functioning self-regulating system that is integrated with the ecological landscape in which it occurs. Often, natural resource restoration requires one or more of the following processes: reconstruction of antecedent physical hydrologic and morphologic conditions; chemical cleanup or adjustment of the environment; and biological manipulation, including revegetation and the reintroduction of absent or currently nonviable native species.
It is axiomatic that no restoration can ever be perfect; it is impossible to replicate the biogeochemical and climatological sequence of events over geological time that led to the creation and placement of even one particle of soil, much less to exactly reproduce an entire ecosystem. Therefore, all restorations are exercises in approximation and in the reconstruction of naturalistic rather than natural assemblages of plants and animals with their physical environments.
The objective is to emulate a natural, self-regulating system that is integrated ecologically with the landscape in which it occurs. Often, restoration requires one or more of the following processes: reconstruction of antecedent physical conditions; chemical adjustment of the soil and water; and biological manipulation, including the reintroduction of absent native flora and fauna or of those made nonviable by ecological disturbances.
An approximate point in time must be selected to develop criteria for restoration. Restoring an aquatic ecosystem to its predisturbance condition may be a difficult problem. For some ecosystems, the fossil record fossil plants, pollen can be helpful. For lakes, paleoecological methods can be used. For prairies, soil core analysis is used. Sometimes what is required is some ''historical investigative ecology. Whereas restoration aims to return an ecosystem to a former natural condition, the terms creation, reclamation, and rehabilitation imply putting a landscape to a new or altered use to serve a particular human purpose creation or reclamation see Glossary, Appendix B , for definitions.
The term restoration is used in numerous regulations and public laws when what is meant is reclamation, rehabilitation, or mitigation. In the statement of purpose, however, the terms restoration and rehabilitation are used interchangeably. Further, the bill deals only with " In a similar vein, a memorandum of agreement between the U. Army Corps of Engineers and the U.
Environmental Protection Agency defines restoration as "measures undertaken to return the existing fish and wildlife habitat resources to a modern historic condition. Restoration then includes mitigation as well as some increments of enhancement. Mitigation for filling a wetland in order to build a shopping center may involve restoring a nearby wetland that had been filled for some other reason, or it could involve creating a wetland on an adjacent area that was formerly upland.
Mitigation need not, and often does not, involve in-kind restoration or creation. For example, the loss of floodwater storage due to filling a wetland might be mitigated by creating a detention basin. Although the functional attributes of flood control are rehabilitated, the chemical and biological characteristics or other functional values of the wetland are not.
Mitigation of frequently and rapidly fluctuating water levels in a flood control reservoir may be achieved simply by altering the release schedule from the reservoir. In this case, mitigation is achieved by reclamation, not by restoration or creation. Preservation is the maintenance of an aquatic ecosystem. Preservation involves more than preventing explicit alterations, such as.
Preservation also implies management e. Preservation is sometimes mistakenly linked to mitigation via the assumption that a preserved aquatic ecosystem at one location will offset or mitigate the losses of displaced aquatic functions at another. Although such preservation may prevent further losses, it cannot compensate for losses already incurred. Preservation is distinct from restoration and creation in that the functions and characteristics of the preserved ecosystem are presumed to exist, more or less, in their desired states. This is not to say that the aquatic ecosystem has not been subject to changes over the years but that the ecosystem is performing in an acceptable manner not requiring reclamation or rehabilitation.
Whether restored, created, rehabilitated, mitigated, or preserved, most, if not all, aquatic ecosystems subject to the pressures of large human populations need to be managed. Management is the manipulation of an ecosystem to ensure the maintenance of one or more functions or conditions.
In the case of preserved, created, or restored aquatic ecosystems, management activities should be directed toward maintaining all functions and characteristics. This is distinct from the management of an aquatic ecosystem for more limited objectives. Controlling water levels in a wetland for duck production is a limited management objective.
Another limited objective is releasing water from a reservoir to maintain in-stream flows for trout fishing. These activities generally ignore the needs of other organisms and bias an ecosystem's characteristics in support of a desired single function. However, management of an aquatic ecosystem need not be limited in scope. Controlled burns of mesic prairies will prevent the introduction of weedy plant species and increase plant and habitat diversity. The management strategy of using beaver to build dams to prevent stream-bank erosion Spencer, may also aid the restoration process when, for example, the beavers graze on woody vegetation and the beaver ponds trap nutrients and sediments Seton, ; Naiman, Selectively restoring a river meander or a chemical characteristic of a lake is not restoring the aquatic ecosystem unless that is the only significant aspect that has been degraded.
To restore the aquatic ecosystem, all functions and characteristics must be considered, an approach that may in practice be difficult to achieve. However, the term restoration should be applied only to those activities directed to rebuilding an entire ecosystem: reconstructing topography without. Although it may seem appropriate to describe as restoration the building of wetlands in backwater areas of a flood control or water supply reservoir, this application distorts the meaning and masks the true purpose of such a created aquatic ecosystem.
These ecosystems may be desired in backwater areas for duck habitat and hunting, water quality management, or even additional flood control. However, such created ecosystems will not possess the full range of physical, chemical, and biological characteristics of their natural counterparts. For example, their hydrologic characteristics will differ markedly from the prototype. The distinctions among the terms restoration, creation, rehabilitation , and reclamation are important, and it is necessary to understand also how these terms relate to mitigation and preservation.
Using consistent definitions, scientists and engineers will be better able to communicate their intentions and activities among themselves, policy-makers, and the general public. This should facilitate setting clear goals and establishing effective programs for improving our environment. This report on the status of our aquatic ecosystems must start with an assessment of the conditions of the land surface. Ninety-seven percent of this country's surface area is land; consequently, most of the water moving into and through aquatic ecosystems interacts with the surface of the land.
Of the land surface in the 50 states, comprising 2. Excluding Alaska, agricultural lands account for 65 percent of the land surface. Of the agricultural lands, 39 percent are grazed and 37 percent are cropped Frey and Hexem, Regardless of the activity, the 1. Grazing, plowing, chemical applications, and drainage have changed the vegetative cover and soil conditions to such an extent that they no longer exhibit the characteristics of preagricultural conditions.
These activities are necessary to support our highly productive agricultural industry, but one of the side effects is the degradation of aquatic ecosystems on a continental scale. Smaller in scale but more extreme in effect is the alteration of the land surface to accommodate urban development. In building cities, wetlands and floodplains have been filled and made impervious by. Although only 3 percent of the nation's land surface is designated as urban, within an urban area, the hydrological and biological changes are extreme. In Chicago, a city of square miles, 45 percent of the land is now covered by impervious surfaces.
The once verdant wet prairies and marshes that dominated the landscape before this great city was built are gone. The roofs, streets, and roads have greatly changed the quantity and quality of water flowing into Lake Michigan and into the Des Plaines and Illinois Rivers. The change in flow was accompanied by a dramatic change in water quality due to the large waste loads conveyed by storm water runoff and by domestic and industrial wastewater. Both the hydrologic and the water quality effects extend miles beyond the limits of the city.
The U. Uplands, wetlands, and floodplains have been drained to build houses, factories, and farms. Approximately million acres of wetlands alone have been lost in the United States since the s Dahl, This represents 5 percent of the total land surface in the 50 states but about 30 percent of the presettlement wetlands excluding Alaska, the wetland loss is approximately 53 percent; Dahl, The effects of increased losses have been harmful, if for no other reason than increased flooding.
The dispersive capabilities of streams and rivers were and are inadequate to handle the large amounts of runoff generated and diverted to them from uplands and former wetlands, which one acted as flood control reservoirs. In , the state engineer for Illinois observed that floods on the Des Plaines River were increasing in severity and frequency Horton, He ascribed this hydrologic phenomenon to the clearing of land and draining of wetlands in the watershed. The widespread loss of U. When one considers the losses from to in the central United States, it is no wonder that floods ravaged the river valleys of the Ohio, Wabash, Illinois, Missouri, and Mississippi.
Unfortunately, wetlands continue to be drained by ditching, and storage areas continue to be blocked by levees, so that flood damage continues to increase. Whereas more than 60 percent of the U. Surface water controls range from very simple fixed weirs to very complex multigated dams and extend from small farm ponds and streams to our largest rivers and the Great Lakes. They benefit us in numerous. Source: Dahl, Geological Survey see Figure 1.
They stabilize lakes at levels that afford reliable access for recreational boating, and they maintain navigational conditions for commercial barges and ships. Manipulation of water levels offers optical flood protection and water supply for drinking and irrigation.
However, the controls also may have detrimental effects on wildlife and other functions of aquatic ecosystems, and wetlands in the littoral zone suffer from either too much or too little water. Dynamic hydrologic cycles are all but eliminated, causing the degradation of plant and animal communities. Of the 2, billion gallons of water available per day in the United States, approximately 4. This total assumes, however, that the availability of water is.
On a sustained basis, perhaps only 25 percent of the water is available on average, so that the consumption rate is thus quadrupled to A much higher percentage is extracted and recycled. Geological Survey Solly et al. This represented approximately 15 percent of the total resource, or 61 percent of the sustained yield. In-stream uses were an order of magnitude larger. The production of hydropower utilizes more than 3, billion gallons per day, an amount that exceeds the available supply but includes the repetitive use of water as. Source: U. Geological survey, Given that there are well over 2.
Both off-stream and on-stream uses change the physical and chemical characteristics of the water. Reservoirs the thermal properties of the waters in rivers and streams by changing the surface area and depth characteristics. During the winter the larger surface areas created by a reservoir release more heat than an undammed stream would have, whereas during the summer they absorb more heat; consequently, the downstream thermal regime is changed.
Thermal electric plants discharge heat to stream, rivers, and lakes via the dispersal of cooling waters. Domestic and industrial including thermal electric uses alter the hydrology at the point of both withdrawal and discharge. The return flows introduce elevated concentrations of nutrients and toxic substances despite modern wateswater treatment technology. Relative to the sustained yield, industrial and domestic wastewaters represents about 32 percent of the water treated. Dissolved solids are adopted to the stream from irrigation return flows and agricultural drainage in general.
These flows account for 12 percent of the sustained yield. The high concentrations of dissolved solids result, in part, from the evaporation of irrigation water. Evaporative losses account for 14 percent of the sustained yield. Other sources such as runoff from roads, parking lots, and farm fields contribute substantial amounts of solids and nutrients to our rivers, lakes, and streams.
EPA, ; Smith et al. Based on an analysis of sampling stations distributed throughout the country, the concentrations of chloride, sulfate, nitrate, magnesium, sodium, and potassium. Smith et al. Suspended solids and pH have also increased at most stations, as have the concentrations of heavy metals, including arsenic, cadmium, iron, and manganese. Although most stations reported that dissolved oxygen increased, a beneficial change, the ratio was only about 3 to 2. Decreases were reported in the concentrations of calcium and phosphorus. Based on analyses undertaken by state personnel, the U.
Environmental Protection Agency has concluded that progress has been made but that much remains to be done U. EPA, However, only , miles of stream were surveyed, 23 percent of the total streams in the United States. The apparent lack of concern for the physical structure of our nation's streams perhaps stems from the fact that no one seems to have very clear idea of how many streams miles there are in the country, let alone their physical, chemical, and biological state of repair. Although basic documentation is lacking, one estimate is that there are more than 3.
An additional , miles are constructed agricultural drains Wooten and Jones, Incorporated into our major river systems are close to 12, miles of inland waterways. For these waterways, navigational channels are maintained at depths of 8 to 16 ft. Along our streams, levees and flood walls traverse an estimated 25, miles Johnston Associated, and enclose more than 30, square miles of floodplain.
The floodplain estimate is extrapolated from the ratio of length of levees to enclosed area for the Upper Mississipi River. Channelization, for navigation or drainage, and levees have drastically reduced the flow area of stream. At the same time, increased runoff from the draining of uplands and wetlands has been forced into the drainage system. The hydrological effects of this loss of storage are enormous.
Nitrogen and Aquatic Systems
The environmental stress and altered characteristics and functions of our aquatic ecosystems caused by dispersive and extractive uses and stream modifications are reflected in the status of our fisheries, as reported by the U. Fish and Wildlife Service Judy et al. Of , miles of perennial U. Water quantity problems resulting from diversions and dams affected approximately 18 percent of the reaches Table 1. The physical limitations most frequently cited were siltation, bank erosion, and channel modifications. Of these, siltation was cited most often and was identified as impairing 40 percent of the miles surveyed Table 1.
This survey was conducted once in and again in Little change seemed to occur over the intervening 5-year period Table 1. Regardless of when the survey was conducted, only 5 or 6 percent of the miles surveyed supported high-quality sport fisheries or exotic species. Minimal or lower-quality species of fish were found in more than one-third of the streams.
Approximately three-quarters of the streams would support only a low-quality sport fishery. TABLE 1. The descriptors of abundance minimal, low, moderate, and high were subjectively determined, the assessment being made by personnel of the U. Fish and Wildlife Service and state fish management agencies.
Because of the highly modified and disturbed state of many of our aquatic ecosystems, particularly those closely associated with large population centers or located in agricultural areas, there is considerable potential for the use of restoration to solve water quality, wildlife, and flooding problems.
A restoration initiative must be broad and also must encompass large tracts of land; yet these areas need not impinge on the economic viability of agricultural or urban centers. For example, restoration of about 50 percent approximately 59 million acres of the nation's lost wetlands millions acres in the past years would affect less than 3 percent Table 1. Of course, most wetland restoration would take place on floodprone land that is uneconomical for farming or other activities.
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Given the million acres of flood-prone land Table 1. The restoration could take place in littoral zones around lakes and reservoirs and along the floodplain, creating circular greenways and along the floodplain creating green corridors. The restoration of river corridors would directly address the recommendations made by the President's Commission on Americans Outdoors The riverways called for in its recommendations fully embrace the concept of riverine floodplain restoration.
If 2, river and stream segments are protected and revitalized as the commission recommended, the 59 million acres of restored wetland could be distributed along these corridors. Given that the average river segment length is miles, the total length of restored river corridors would be , miles. This would be only 2. Distributing the 59 million acres of land along the stream and river segments would create a corridor with an average width of 1, ft. Lakes provide many examples of why abatement of pollutant loading is a necessary but often insufficient step toward improving and restoring freshwater quality and quantity, and ecosystem functions.
Many lakes have lost significant storage capacity through siltation, which reduces their recreational and water supply usefulness, impairs. Siltation also remains a serious problem in the United States; 1. Department of Agriculture, Pollution abatement alone will not return many lakes and reservoirs to their former condition because nutrients and toxic materials are recycled from lake sediments.
These processes maintain eutrophic conditions or continue to contaminate food webs and associated fisheries, even though loading has been reduced or eliminated. Invasions and planned introductions of nonnative species have become serious problems, impairing fisheries or recreational use see Chapter 4 for further details. The extent of lake damage in the United States is substantial. A recent survey by the U. Environmental Protection Agency indicates that about 2. By far the most common source of stress leading to impairment is agricultural activity almost 60 percent of impaired acreage is attributed to this source ; nutrient and organic enrichment and siltation problems are the most common causes of impairment.
It must be noted, however, that survey information regarding some problems such as exotic species and toxic metals is grossly inadequate. These lakes and reservoirs, and others like them, require active restoration and subsequent protection and management, in part because sites for new reservoirs are rare or absent in most areas of the United States Brown and Wolfe, Acidified lakes will recover only slowly after cessation of sulfur deposition and may require significant restorative efforts Schindler, ; Schindler et al.
Streams and rivers perform numerous ecological and economic functions. They are conveyances; diluents; sources of power generation; sources of potable water, water for industrial uses, and water for irrigation; and recreation sites. Unfortunately, multiple problems afflict many U. Our rivers have been diverted, dammed for navigation and hydropower FERC, ; Benke, , channelized, polluted, their wetlands removed, their basins silted in from soil and bank erosion, and their sediments contaminated with toxins.
The combination of dams on the upper Mississippi River and levees along the lower Mississippi has reduced replenishment of the Mississippi delta by sedimentation during the annual floods and thereby contributed to the problem of land subsidence, shoreline erosion, and loss of coastal marshes Keown et al. More than half of the nation's rivers have fish communities adversely affected by turbidity, high temperature, toxins, and low levels of dissolved oxygen.
Almost 40 percent of perennial streams in the United States are affected by low flows, and 41 percent by siltation, bank erosion, and channelization Council on Environmental Quality, The problems affecting aquatic resources cannot be solved without examining the deleterious land management practices that contribute to those problems.
For example, failure to control wind and water erosion and destruction of forested riparian areas has produced heavy silt loads. Increased sediment delivery resulting from forestry practices has also increased sedimentation and turbidity in downstream channels, lakes, and reservoirs, with attendant loss of capacity for water storage and conveyance, recreational and aesthetic values, and quantity and quality of habitat for fish and wildlife.
Low or nonexistent dry season flows are one result, leading to water shortages, elimination of river biota, and the increased potential for flash floods. Annual sediment loads in major rivers range from million to 1. One of the major items in the budget of the U.
Although there have been measurable improvements in stream quality over the last 20 years in the United States, these are associated primarily with improvements in municipal wastewater discharges Smith et al.
River sediments remain contaminated with toxic substances in many areas, flash floods are common and occasionally lethal, costs to treat water prior to its use have increased, and streambeds remain covered with silt. Vast stretches of rivers and streams have been channelized, a practice that destroys wetlands; increases sediment, nutrient loss, and bank erosion; and often eliminates streamside vegetation that is essential to maintain cool stream temperatures and to stabilize banks. Thousands of miles of rivers and streams are affected by acid mine drainage. Eight percent of the samples of 59, stream segments 21, km examined in the National Surface Water Inventory between and were.
A systematic restoration of U. Wetlands provide essential functions, including flood control, soil and nutrient retention, and wildlife habitat. In some agricultural areas such as the state of California, more than 90 percent of the natural wetlands have been drained or filled. Many riverine wetlands, so essential to water storage, aquifer recharge, and wildlife, have been converted to agricultural areas or destroyed by channelization and urban sprawl. The average rate of wetland loss in the conterminous United States from the mid's to the mid's was nearly , acres per year, leading to an aggregate loss over all time of about half the wetlands believed to have been here before settlement began — an area greater than Massachusetts, Connecticut, and Rhode Island combined The Conservation Foundation, ; Council on Environmental Quality, The rate of wetland loss declined to approximately , acres per year from to Dahl and Johnson, Although a ''no-net-loss" policy for U.
During his campaign, then-Vice President Bush declared that all existing wetland should be preserved. His stand was an endorsement of a no-net-loss policy recommendation made by the National Wetlands Policy Forum, a broadly based group including representatives of both industry and environmental groups.
In , the U. Environmental Protection Agency and three other federal agencies implementing wetlands protection provisions of the Clean Water Act of P. This federal manual confirmed a U. Fish and Wildlife Service estimate that million acres of the nation are wetlands. Since the appearance of the manual, however, a number of interest groups, lawmakers, and several federal agencies urged the administration to make the definition of wetlands less encompassing, thereby reducing the amount of land designated as wetlands.
These groups have contended that the federal definition of wetlands contained in the wetland delineation manual was so broad as to include areas that are not truly wetlands and that have long been regarded as dry. It is essential that this matter be resolved in order to develop a workable restoration policy. In response to the criticism, the Bush administration has now developed a new definition of wetlands that would permit construction and farming on up to 10 million acres of land previously classified as wetlands and off limits to development Schneider, ; representatives of the Environmental Defense Fund, an environmental group, have asserted that the new definition would allow the development of up to 30 million acres — one-third of the nation's remaining wetlands.
The new definition has had strong backing from the administration's Council on Competitiveness, chaired by Vice President Quayle. At best, even the original no-net-loss policy meant only no further loss in the aggregate of wetland function or area. Hence, it meant no net return of lost ecological functions and no increase in the nation's wetland area. To recover some of the lost area and functions e.
In view of the tremendous losses that have been sustained by the wetland resource base, our national goal should in fact be a net gain in wetlands, rather than no additional loss. A similar line of reasoning leads us to believe that, at a minimum, a no-net-loss policy for all other aquatic resources should be implemented as well. Detailed national studies should be conducted of wetlands and of each major aquatic resource type to set national goals for achieving net gains in all aquatic resources through resource restoration.
This report presents major elements of an agenda for restoration of aquatic resources. Although the details of this agenda will have to be articulated by scientists, public officials, and citizens working together, some characteristics of a national restoration strategy are already discernible. In the broadest terms, aquatic ecosystem restoration objectives must be a high priority in a national restoration agenda: such an agenda must provide for restoration of as much of the damaged aquatic resource base as possible, if not to its predisturbance condition then to a superior ecological condition that far surpasses the degraded one, so that valuable ecosystem services will not be lost.
Despite a continuing national pattern of loss of aquatic resources in area, quality, and function, comparatively little is being invested today on a national scale to restore aquatic ecosystems. Although no reliable estimate of current national spending on aquatic ecosystem. This sum is tiny relative to the multibillion-dollar scale of investments made in water development and pollution abatement. Numerous restoration projects at all levels of government and by the private sector are significant and promising, but unfortunately, the vast majority are small in scale and uncoordinated on a regional or a national basis.
Much more restoration of aquatic ecosystems is needed to slow and reduce the loss of national aquatic resources, ecosystem services, and wildlife. Concurrent with the overall decline of aquatic resources, demographic and climatological trends are threatening to exacerbate the underlying ecological problems that make aquatic ecosystem restoration necessary. The world's population is now increasing at a rate of 90 million people per year, adding the equivalent of more than the entire U. If the United Nations has projected correctly that the world population will be 9 billion people within 40 years, global demand for water, as for other resources, will increase greatly, causing water shortages and further damage to aquatic ecosystems Postel, Coupled with the likelihood of significant global climate change Abrahamson, ; Cairns and Zweifel, ; Schneider, a; Ehrlich et al.
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Typical projects include: sub tidal transects, instrument deployment and recovery, scientific collections, etc. ARG designs and fabricates custom aquatic systems for research and public education. By arrangement, ARG can design and install custom systems for off-site research and public displays. The Aquatic Resources Group is permitted by the California Department of Fish and Wildlife to collect and ship a wide variety of marine organisms to research and educational facilities. Collected specimens are meticulously packed and can be shipped locally, nationally, or internationally.