Taxonomy and Ecology Of Inland Sand Dune ... - Mycorrhizae

58could reduce water evaporation andchange soil pH.Sand dunes along the vegetated transectare 100% vegetatively controlled. Thevegetated transect showed the highestpercentage mean of MIP (22.54 ± 2.32).This observation confirms Halvorson andKoske (1988) work at Moonstone Beachof USA when they found that VAMfungal inoculum density was positivelycorrelated with plant cover. Thereduction in MIP percentages at thevegetated stands along the vegetatednonvegetatedand the disturbedvegetated-nonvegetated transects couldbe related to the decline of the aboveground cover which was (47.05%) at theformer and (31.25%) at the later. Thenon-vegetated sand dunes along thevegetated-nonvegetated transect showedless MIP percentages (2.06 ± 1.28) thanthe non-vegetated sand dunes along thedisturbed vegetated-nonvegetatedtransect (18.14 ± 5.68). Such differentmight occur through disturbance by thehigh activity of people driving dunebuggies or riding dirt bikes. The highpercentage of colonization at the activeand disturbed sand dunes might be as aresult of scattering fungal spores, hyphae,or infected root fragments from thevegetative area. Each propagule couldestablish mycorrhizal association ifproper condition and pioneer host areavailable. In similar study Miller (1979)found Glomus spp. propagules fromWyoming disturbed Red Desert gave43% infection in Agropyron smithii Rydbverses 41% infection in the same plantsgrown at native soils. Also, Sward et al.(1978) found that a large number of"Endogone" spores in the disturbed areathat correlated with the rainfall amounts.In other work by Johnson (1977) at NewZealand coniferous dicotyledonous forestindicated that VAM fungal sporesrepresented in variable densities (2-17 X10 3 l - ) of unrelated distribution to thehost plants.As more investigation on the role ofmycorrhizal fungi in vegetated anddisturbed soils, it is becoming evident