Record Display for the EPA National Library Catalog


Main Title Effects of Divalent Metal Chlorides on Respiration and Extractable Enzymatic Activities of Douglas-Fir Needle Litter.
Author Spalding, Brian P. ;
CORP Author National Heart, Lung, and Blood Inst., Bethesda, MD.
Year Published 1979
Report Number EPA-600/J-79-109;
Stock Number PB81-106064
Additional Subjects Carbon dioxide ; Metals ; Fir trees ; Pollution ; Mercury(Metal) ; Cadmium ; Lead(Metal) ; Nickel ; Zinc ; Copper ; Chlorides ; Respiration ; Enzymes ; Reprints ; Pseudotsuga menziesii ; Water pollution effects(Plants)
Library Call Number Additional Info Location Last
NTIS  PB81-106064 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 8p
The rates of CO2 evolution from Douglas-fir (Pseudotsuga menziesii Franco) needle litter, following application of divalent metal (Hg, Cd, Pb, Ni, Zn, and Cu) chlorides at rates of 10, 100, and 1,000 microgram/g and Ca chloride at 7, 68, and 683 microgram/g were monitored at 2- to 3-day intervals for 4 weeks; extractable enzymatic activities, were also measured on additional samples 1 day, 2, and 4 weeks following treatment. All metals except Pb inhibited respiration when applied at the highest level. Cellulase activity was depressed by treatment of 1,000 microgram/g of either Hg or Cd after 4 weeks but was not affected initially (1 day after). After 4 weeks, xylanese activity was also depressed by the 1,000-microgram/g Hg treatment. Apparently these enzymatic activities declined due to decrease enzyme synthesis associated with inhibited microbial growth rather than by direct enzymatic inhibition.