TITLE:
Soil Nutrients Can Influence Exotic Species Richness in Urban Areas: A Case Study from the City of Kolkata
AUTHORS:
Seemanti Chatterjee, Anjana Dewanji
KEYWORDS:
Urban Area, Species Richness, Soil Physico-Chemical Parameters
JOURNAL NAME:
American Journal of Plant Sciences,
Vol.10 No.11,
November
28,
2019
ABSTRACT: Urbanization contributes to extensive land use
changes and environmental degradation which may influence changes in soil
properties. These abiotic changes may aggravate invasions and favour the
distribution and number of invasive species in urban areas which could
negatively impact biodiversity. This case study was, therefore, undertaken in
the metropolitan city of Kolkata to assess the existing plant species richness
(both native and exotic) and to determine the relative role of some soil physico-chemical
parameters on species richness. Plant species were recorded and soil samples
were collected from each study site. The total species richness ranged from 4
to 25 with 50% of sites having a median number of 11 species. The presence of
at least 3 or more invasive species was observed in >80% of sites. The mean
and median values of soil parameters showed considerable variation in soil
properties between sites. Urban soils had elevated pH values and higher
available N, P and Ca. Soil available N appeared to be significantly correlated
with both total species and exotic (including invasive) species richness while
available phosphorus showed significant correlation with only exotic species
richness. The GLM Poisson log-linear models showed a significant positive relationship
of soil N with total species richness and exotic richness including invasive
species richness in the study area.