|
<br />I'"
<br />l'-
<br />
<br />'.')
<br />(:~
<br />C'
<br />
<br />Grand Junction is characterized by fairly consistent light
<br />valley breezes. averaging 8.2 mph and a maxima at 66 mph, New
<br />Orleans, Louisiana, an area noted for extensive saline marshes,
<br />has co.parable velocities, averaging 8.4 mph, with recorded
<br />maxima at 69 mph (see Ruffner and Bair, 1977), Acceptable
<br />air-leaf surface gas exchange thus can be anticipated.
<br />
<br />r--
<br />
<br />3, Insolation
<br />
<br />A major difference between coastal salt marsh and Grand Junction
<br />environments is seen in the quantity, quality, and patterns of
<br />solar radiation, New Orleans, for example, averages 389.8
<br />Langleys year ~ound, with a minimum during Decembe~ of 211.4 and
<br />a maximum during May of 543,5 (see Knapp, et al. 1980). This
<br />translates to an average total of about 142,000 Langleys pe~
<br />year for the area, compared with an average solar flux in Grand
<br />Junction of 122,000 Langleys during its characteristic seven
<br />month agricultural growth season, Thus, in seven months, Grand
<br />Junction receives 86% of the total amount of sunshine New
<br />Orleans receives all year.
<br />
<br />4, Temperatu~e
<br />
<br />o
<br />New Orleans has an average monthly temperature of 68.3 F,
<br />~anging from a daily minimum of 43.5 of in January to 90.60F
<br />in August (see Knapp, et aI, 1980). This is sufficient to
<br />provide a year round growth opportunity for emergent salt marsh
<br />plants, something not likely to be available to crops grown in
<br />Grand Junction,
<br />
<br />5, Humidity
<br />
<br />Humidity is of major importance because it is a determinant of
<br />transpiration, resulting in part from the partial p~essure
<br />differential for water in the atmosphere and in a leaf,
<br />Although this will be discussed mo~e fully within the next
<br />section, with other parameters held equal, transpiration will be
<br />proportionately g~eate~ in a~eas of lower humidity,
<br />
<br />Coastal salt marshes are characteristically associated with high
<br />~elative humidity. This fluctuates in New Orleans from 85% to
<br />88%, 63%, and 71% over the course of an average day, and is
<br />consistent year round, Humidity in Grand Junction is almost 50%
<br />lower than New Orleans during its growth season, This indicates
<br />that Grand Junction is not a good place to grow water
<br />inefficient plants, if water is a limitation in the process,
<br />Yet, if wate~ inefficiencies are desired, as in the STEP
<br />process, this is a desirable feature,
<br />
<br />6, Precipitation
<br />
<br />In keeping with higher humidity and lower insolation, coastal
<br />salt marshes are characterized by higher amounts of annual
<br />precipitation, The historic average rainfall in New Orleans is
<br />
<br />;.,/
<br />
<br />10.
<br />
<br />.t,~
<br />
|