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<br />mm mmmm
<br />Chapter 5. Wetlands
<br />w«tl*nrf^ tk thinking of
<br />tew fviirA^*'* »thcrte lying areas that during some portion of the year are
<br />c^wl in part by natural nonflood waters-os the
<br />breeding grounds for disease. Yet the tendency to see
<br />marshes and bogs as wasteland has produced the major
<br />theme m Amenca’s management of wetlands: the
<br />conversion of these habitats to supposedly better uses.
<br />bo-called reclamation of wetlands has been public policy
<br />years. In 1850 the federal government
<br />provided Swamp Land Grants’* to enable states to
<br />^he “swamp land in their limits.** When a state
<br />sold the land the proceeds were to be used '’exclusively as
<br />far as necessary to the reclamation of said lands.** Later
<br />the Federal Swamp Land Acts authoru»d the draining and
<br />,1.1!!® acres of wetlands. In the 1920s and
<br />19J0S, the marshes and bogs in Iowa, Missouri, Illinois,
<br />Indiana, Ohio, Michigan, and Wisconsin w'ere reduced to
<br />10 per cent of their previous size. Since World War II the
<br />wet prairies of Minnesota and the Dakotas have been
<br />drained extensively. Nearly 350,000 acres, or 25 per cent
<br />of that region’s waterflow-producing potholes, arc gone '
<br />the most severe changes have occurred in the
<br />midwestern states, but the problem is extending to the
<br />&uth and along the Atlantic coast. A U.S. Department of
<br />the Interior report of 1967 shows that 7.1 per cent of the
<br />23 per cent severely
<br />nn^ifi^. ^1,forma alone has lost 67 per cent of its coastal
<br />wetlands. Overall, it is estimated that in the past 100
<br />American wetlands have been reduced to 70
<br />million acres, slightly more than half the original acreage
<br />« .n».Ud at 127.miUion acres." NeverthelerJ; every state
<br />With significant wetlands is stUI experiencing pressure for
<br />the conversion of these lands to either agricultural or
<br />urban uses.
<br />Land developed for increased agricultural production
<br />has accounted for much of this loss, but the more recent
<br />phenomenon of urbanization has taken its toll
<br />Urban conversion of wetlands occurs be« ause’ real estate
<br />value ,8 not influenced by the value of wetlands. An
<br />individual is unlikely to pay for a lake’s natural filtering
<br />system or the nesting sites for herons, cranes, and other
<br />waterfowl. House and Home pointed out the potential of
<br />wetlands in April 1958: “Some of these are in areas close to
<br />town that have been passed over while higher land all
<br />around has skyrocketed in price. Yet the marshy land can
<br />sometimes be bought and filled in for much less than the
<br />cost of surrounding land.*'*
<br />Wetlands are the builder’s dream of cheap land. There is
<br />no doubt that real estate values are one of the major
<br />causes of wetland destruction. California’s wetland
<br />inventory in 1958, for example. wa.s down to 500,000 acres
<br />from an e.stimaled two million in less crowded days.* The
<br />Ip-eater the increase in land values from urbanization, the
<br />greater the iinpiftus to take advantage of the low market
<br />price of wetlands.
<br />1 here is one- more turn of this economic .screw. Wetlands
<br />not only suffer from the cataclysmic changes of dredge and
<br />fill; they also suffer from less dra.stic. everyday uses th.it
<br />otcur on their borders and cause an incremental loss of
<br />quality. 'I'he housing development .sit ting on the hill above
<br />a marsh dumps runoff, silt, fertilizers, and other
<br />by-products of urban living into the mar.sh. Similarly, the
<br />incremental effects of agriculture can destroy a marsh or
<br />bog. Fertilizers leach into the wetlands, and plowing
<br />increases the silt flow. The people on the hill then
<br />exrieriena! the tragedy of the commons: they lf>cat«I there
<br />because they liked the open space, the access to rivers and
<br />lake.8, and the variety of wildlife, but their actions destroy
<br />tht^sc fiiilurcil benefits.
<br />Society has not found out what the actual credits and
<br />debits of tievelopment of Its wetland resource, are.
<br />I hough there has been little .systematic work in evalu iting
<br />the consef|Ut Mces of converting wetlands to other uses
<br />bits aiul pieces of evidence indicate th.it the bent fits are
<br />not without liabilities. It has been .shown, for example,
<br />that the peat soil of wetlands is not always g .od farmland.
<br />Uotland.s are low-lying areas subject to early frosts, and
<br />Sinct- the pe;it relea.ses nutrients too slowly and too
<br />uneveiviy to prt.vitle fertile soil, ultimately it require,^ more
<br />fertilizer than «,thcr farmland. As a consetpience drained
<br />land has previously ended up in .soil hanks rather than in
<br />production. Likewise many converted wetlands have not
<br />proved to be good home sites. 'I'he canals of the new
<br />\enices m Calih.rnia and Florida have quickly become
<br />chokwl with aIgMe, leaving homes sitting on the banks of
<br />lagoon.s tliat more nearly resemble open sewers.
<br />Although llH-.se problems remain unresolved, there has
<br />bt?en a significant shift in both public attitude and public
<br />iMihcy since the early 1960s. Where the older laws were
<br />devoted to protecting xvetlands only as a corollary to the
<br />protection of fish and wildlife (Migratory Hird
<br />( onservaliou Act. 1929; Wihllif,. Itesloratinn Act. 193.|:
<br />Hsh Kestoraiion and Management Act. 1950), recent
<br />legislation and policy statements are focu.sed on the
<br />wetlands thcm.selve.s as the resource to he proteeted
<br />preserved, ami restored (Kstuarine Areas Act 1972-
<br />Art. 1972). Likewise i:, ..\prii
<br />19..). the Lnvironniental Frotecti.m Ag.nc> annumav,! a
<br />new pohey to actively protect and pre.serve the nation's
<br />j amis and omhned four .spe cific jHilicy g<.als in .supi.nrt
<br />of this general stance: **
<br />3
<br />I To ininimi.
<br />the n.iliiral flow
<br />pro|«vl them fn
<br />solid-waste man
<br />ditioii of pesticul
<br />nonfmint-soiirce
<br />and to prevent
<br />standards.
<br />2. 'I’o deny fee
<br />waste water tresi
<br />the existing a
<br />alternative of li
<br />feasible.
<br />3. To consult
<br />determining the
<br />programs on fish
<br />4. To rccommi
<br />projected signific
<br />While these pol
<br />significant chang
<br />April 1974, the
<br />similar set of gi
<br />Rivers and Harbo
<br />During the past
<br />have also begun n
<br />wetland protectioi
<br />and Atlantic coas
<br />have passed legis
<br />effort has been tc
<br />filling of wetland!
<br />require a state peri
<br />therefore difficult
<br />that the rate of i
<br />Similar systems c
<br />instituted by mu:
<br />response to state r
<br />cover wetlands devi
<br />restrictic,.; dredge i
<br />described in detail
<br />WETLAND EC(
<br />Wetlands are <i
<br />land and open wi
<br />poor drainage, ai
<br />yearly variations
<br />sometimes hard t
<br />may be dry throi
<br />during years of
<br />extensive than in
<br />Though it is dil
<br />definition of exact
<br />begin, wetlands
<br />vegetation, w’ater
<br />depth. Wetlands
<br />marked difference
<br />Table 2 lists the ^
<br />these factors, alo
<br />disturbance. It is I
<br />habitats by the U.
<br />Analyzing a cor
<br />ecological types |
<br />resources living cor
<br />38
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