Abstract:
Home gardens are multistoried ecosystems and are important not only for in-situ biodiversity
conservation, but also as valuable food sources, fodder, medicine and spices. The main objective of
this study was to make decisions about the variations of home garden composition and to identify the
endemic species. Fifty five home gardens were studied in northern flank from January to April 2012.
Two large (10x10m2) and four small (1x1m2) quadrates were studied in each home garden. Individuals
. 1.5 m height and . 1 cm DBH were measured to calculate IVI. Species identification was done on
site and further at the National Herbarium, Peradeniya. Total of 1335 individual woody-perennials and
4603 herbs were found in 11,000 m2 of study area. One hundred and fifty two woody-perennial species
(19 endemic, 44 naturalized exotics, 37 cultivated and 52 timber) under 54 families and 56 herb
species (46 medicinal) belonging to 33 families were recorded. Euphorbiaceae was the dominant
family with 15 species, followed by Fabaceae (11 species), Anacardiaceae (10 species), Rutaceae (10
species), Myrtaceae (7 species), Rubiaceae (6 species), Arecaceae (6 species), Moraceae (5 species),
Sapindaceae (4 species) and Zingiberaceae (4 species). Highest number of plant families (43) was
recorded in Pitawala, while the lowest number of plant families was recorded in Polommana (24).
Based on the Importance Value Index (IVI), the species to pay highest priority for conservation were
selected. According to Shannon diversity values for different villages, Rathninda is the most stable and
less disturbed, whereas Polommana is the most unstable and highly disturbed village. There were five
endemic Anacardiaceae species (Campnosperma zeylanicum, Mangifera zeylanica, Semecarpus
coriaceae, Semecarpus nigro-viridis, Semecarpus walkeri). Twelve percent of the studied population
were interested in timber trees such as Tectona grandis, Melia azedarach, Swietenia macrophylla and
Chloroxylon swietenia. Twelve percent of the studied population preferred fruit trees while 5% were
interested in some medicinal plants. Preference of this nature indicates that in the future, the plant
diversity in these home gardens is likely to decline considerably. This might even lead to the
extinction of rare, endemic plant species. Therefore, people in northern flank encouraged to
incorporate multipurpose endemic plants and plants with less IVI values in their home gardens in
order to maintain high diversity and to conserve endemic and relatively rare plants while gaining
substantial income through their home gardens.
