Airborne pollen grains of Visakhapatnam : A combined field and air sampling study

摘要: Field assessments at regular intervals from April 1975 to March 1979 recorded 61 plant species comprising 13 grasses, 20 weeds and 28 trees shrubs as emitting appreciable amounts of pollen into the atmosphere Visakhapatnam. The data also showed relative prevalence these taxa in different zones city their flowering periods. Pollen output terms number per anther flower was determined for 29 taxa. Air sampling with rod traps 0·53 cm diameter enabled identification 23 types Poaceae accounting Ca. 37% total load.Casuarina contributed 13% followed by Cyperaceae 6%,Eucalyptus 5·8%,Dodonaea 3·8%, Amaranth-Chenopod andPhoenix each 3·4%,Borassus 2·4% andPeltophorum 2%. Of identified pollen, ca 85% belonged anemophilous There no pollen-free day. individual displayed seasonality quite closely corresponding blooming seasons source plants. Three peaks, two wet period (June–November) one dry (December–May) were evident. Year year variations abundance occurred urban growth affected frequency pointing need routine monitoring atmosphere.