Ecological status, threats and future trends of wild Olive (Olea ferruginea Royle) in Dumera forest near by Ziarat, Balochistan

Abstract

The wild Olive (Olea ferruginea Royle) forest is composed of patches stands and grows naturally in an isolated transitional zone
and remote valley of Dumera close to Ziarat Juniper Forest in Balochistan. Twenty forests stand dominated by Olea tree species
were sampled in 2019. Plant composition, density of ha ־¹and area m² ha־¹, health status, sex ratio, estimated number of fruits of
Olea, age, growth rate and soil analysis of forest land wild nature has been studied. Based on relative frequency values, shrubs
(Spirea boissieri) were found dominant, followed by grasses (Stipa himaliaca) while herbs (Nepeta glomerulosa) were contributed
as third dominant in the study area. Density of O. ferruginea trees (>6 cm dbh) ranged from170 to 352 trees haˉ¹ with overall
mean of 427±170 trees ha-¹; the average basal area recorded was 538 m² ha-¹. Satisfactory recruitment might be to better humid
condition of transition zone of O. ferruginea was observed. Highest seedling (< 6 cm dbh) density was recorded from the northeast
facing slope while tree density was higher on the west facing slopes. Results revealed that healthy trees were dominant
(36%), followed by unhealthy trees (21%) and over mature (07%). The sex ratio showed predominance of female as compared to
the male across all the stands. The average tree age of O. ferruginea is 222 years, with the oldest age (434 years) recorded from a
50 cm dbh tree. Growth rate ranged from 5 year/cm to 17 year/cm. Trees with thick fruits were found abundant as compared to
trees with low fruits. Sized class structure showed diverse forms in various stands. The study showed the predominance of small
individuals in the Dumera forest. Two population phenotypes have been recorded, namely the inverted J shape and the irregular
phenotype. Soil variables were not correlated with density and ground area. Increased human population, fuelwood collection,
overgrazing, illegal cutting, debarking and agriculture extension are the major threats. Present situations are threatening and
alarming. Therefore, urgent actions, management and conservation plan should be initiated to rehabilitate and save these forests
for upcoming generations.