Acidic rainfall is harmless under natural conditions
UNIVERSITY’ PARK. Despite;
much controversy, not all add rain '
is harmful, says James A. Lybchof
the School of Forest Resources at,
Penn State.
Acidity from natural rainfall'has
caused no apparent environmental
damage, Lynch stated in < the
summer issue of “Science .in,
Agriculture/’ the quarterly
magazine" of the Agricultural
Experiment Station at Penn State.-
The problem comes when" man
made pollution is added to natural
acid rain, he affirmed.
He saidthe natural acidity of
rain, snow, sleet, and hail is
beneficial in breaking down the
earth’s crust while releasing
nutrients to plants and animals.
Lynch is a forest hydrologist
studying the effects of acid rain on
small streams. He reported that
naturally-occurring acidity rarely
damages f wests' and farm crops.
“Precipitation is naturally
acidic due to the reaction of at
mospheric moisture with normal
levels of carbon dioxide in the air,
and the presence of other acid- ,
forming substances from natural
sources, "he commented.*
Acidity in ram and other
precipitation is expressed by its pH
value. On a scale of zero to 14, a pH
of 7 is neutral. Solutions below 7
are acid. Values above 7 are
alkaline. Where uncontaminated
by man, precipitation has a pH of
5.6t05,7.
Adding manmade pollution to
acid ram produces an average pH
of about 4.1 m the. Northeast, Dr.
Lynch noted. .This occurs when
sulfur<and nitrogen oxides from the
burning of fossil, fuels —by in
dustries* autos, and power plants—
react with natural precipitation to
formsulfunc and nitnc add.
Fortunately,- certain .mature!
substances in the earth and at
mosphere' can- .neutralize, or
••bu£fer” acids. If a watershed is
alkaline, for example—containing
limestone or bicarbonate—the
lakes and streams in the area will
not be affected strongly by acids.
“Fertilized farqa soils are less
likely to becomejfcidic from rams
than nutnent-poor forest soils,” he
said. The fertilizer acts, -as a
buffering agent and 1 , replaces
nutrients leached by acidic rains.”
He claimed the most dramatic
effects of acad rain have been
observed in lakes and streams. For
several decades, declining pH of
lake-waters in the Northeastern
states' and Canada has been
associated with acid ram.
More than half of the remote
mountain lakes above 2000 foot
elevation in the- Adirondack
' Mountains of New York have pH
values below 5.0. Ninety percent of
these lakes now contain no fish. In
Contrast, only 4 percent of the
lakes had ? pH under between
Pa. fieldwork gears up for
HARRISBURG Harvest of rated 67 percent adequate and 33
Pennsylvania fruit and vegetable* percent short,
crops was in full swing during the The state’s tobacco crop is 60
week ending September 7, percent harvested compared with
pitfrnngh showers - limited farm 51 percent harvester at this time
fieldwork to two days, according to last year. Statewide, the potato
the Pennsylvania Crop Reporting drop is 44 percent harvester
Service. Field activities during the compared with 40 percent last
' week included harvesting ensilage year. In the north 29 percent was
com, potatoes, tobacco and ap-' harvester, while 50 percent was
plesr planting wheat; baling harvester in central regions and 52
straw; fixing fences; repairing percent in the south,
machinery; spreading manure. Com for grain in Pennsylvania is
lime - and fertilizer; clipping 44 percent in dough, 45 percent
pastures; and plowing. dented and seven percent mature,
In most areas of the state, the compared with 43 percent in
sweet com crop was reported as dough, 44 percent dented and less
excellent although com borer did than five percent mature. In the
some damage to the late varieties, north 49 percent was reported in
Green pea yield was reported dough, 36 percent dented and eight
good; cabbage and tomatoes are percent mature. The central
looking good although tomatoes region reported 46 percent in
are ripening slowly; cantaloupes dough, 51 percent dented and less
and melons are having vine than five percent mature, while the
problems due to the dry weather; southern region reported 32 per
and apples and peaches have sizes cent in dough, 56 percent dented
up Very well. ' - and 11 percent mature. Ensilage
Topsoil moisture in Qie state was - com is nine percent complete
rated’ .43 percent adequate, _34 compared with 16 percent last'
percent surplus and 23 -■* : 1 :
short., Imthe -north,«soil moisture? * ■ FalT’plownijfsn
was 47 percent surplus, 41 percent -wealth is 36 percent complete, on a
adequate and 12 percent short, par “with last yfear. The north re-
Central regions rated soil moisture ported 29 percent complete, the
45 percent surplus, 33 percent short
and 22 percent adequate, while
southern regions soil moisture was
1020 and 1037 and fish were
abundant *
Rapid changes in stream pH
have been noticed during mtense
storm. runoff or snowmelt.
Changes in pH from 7.0 to 5.5 have
been measured during storms in
___ central Pennsylvania. This in-'
" dicates a sharp increase in acidity.
“These rapid shifts m pH may be
more harmful to streamlife than
gradual, long-term Increases in
acidity,” Lynch reported.
“Various aquatic organisms may
not be able to adjust themselves to
a rapidly changing environment,"
he added.
Lancaster Farming, Saturday, September 12,1981—A23
The most serious, plant injuries
due to acidity create lesions or
brown spots on foliage. In addition,
protective waxes are eroded from
leaf surfaces. Such injuries may
also increase the chance that
plants can be infected by diseases
from bacteria and fungi.
The outcome of injuries is
reduced plant photosynthesis,-the
process by which plants convert
sunlight, into carbohydrates.
Lower photosynthesis reduces
plant growth~and decreases a
plant's chance for survival. -
Acid ram may also affect
domestic water supplies, he
central region 52 percent complete
and the south 32 percent complete.
Third cutting alfalfa was rated
as 57 percent complete compared
with 63 percent last year. The
northern region reported 30 per
cent of the third cut harvested; the
central region reported 61 percent
harvested; and the southern region
reported 78 percent harvested.
Fourth cutting alfalfa was report
ed as nine percent complete stater
wide compared with 11 percent last
USDA revokes N.Y.
produce firm’s license *
NEW YORK, N.,Y. - Eastco
Potato Distributors, Inc.,
Riverhead, N.Y., has had its
produce trading license revoked by
the U.S. Department of
Agriculture for failing to pay a
reparation award of 63,618 for
.potatoes shipped during July, 1079.
USDA’s Agricultural Marketing award is paid. The firm’s sole
{Service, which licenses produce _joffieer, director, and stockholder
firms under . the Perishable Fred Juliano, Jr.—may. not be
Agricultural Commodities Act, employed by or affiliated with any
had charged the firm with failing pACA licensee without USDA
to pay the agreed purchase price to approval.
cautioned.. Concentrations of toxic
metals; such as aluminum and zinc
and nutrient ions are highest
m acidic water. If these particles
are transferred to surface and
groundwater, the quality may
deteriorate.
Further details are given in the
Summer issue of “Science in
Agriculture.” The magazine
features articles on research,
extension, and resident education
in the College of Agriculture. For
free copies, write to 22S
Agricultural Administration
Building, University Park; PA
16802.
harvest
year. The northern and central
regions reported five percent of file
fourth.cut harvested, while the
southern region reported 14 per
cent harvested.
The second catting of clover
timothy' was rated as 85 percent
complete compared with 93 per
cent last year. The northern region
reported 83 percent complete, the
central region 84 percent complete
and the southern region 89 percent
complete.
a Maine shipper.
Charles Brader, marketing
official with AMS, said the firm
answered the shipper’s charges
but that, based on the evidence,
USDA ruled that the shipper was
due the amount claimed.
The firm is ineligible to conduct
business subject to the act until the