INFLUENCE OF SELECTED BOTANICAL GARDEN STRUCTURE,PLANNING AND DESIGN ON ECOSYSTEM SERVICES AND ATMOSPHERIC AIR QUALITY
No Thumbnail Available
Date
2018
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
UNIVERSITY OF ILORIN
Abstract
Pollution due to smoke, dust and other pollutants posed serious challenges to atmospheric air and human health. The study was to investigate the influence of selected botanical garden structures (BGS), planning and design on Ecosystem services (ESS) and atmospheric air quality (AAQ) in Lagos, Ibadan, Akure, Ilorin, Kano and Jos universities botanical gardens (BG) in Nigeria. The objectives of the study were to: (i) identify and determine landscape status (LS) of tree species (TS); (ii) identify tree crown characteristic indices (TCCI) for shade and shelter; (iii) determine TS air pollution tolerance index (APTI); (iv) determine level of air quality index (AQI); and (v) design BGS prototype with TS that can enhance provision of ESS.
Study areas were divided into several plots using transects lines for TS and lichens (L); samples were collected from each plot, frequency values (FV) for TS and L were used to determine the LS. Cluster analysis (CA) of the TS and tree crown characteristics indices (TCCI) were performed, by assigned codes 1 – 6 to the taxonomic character (TC) in ascending order according to the observation and measurement. Ascorbic acid, relative water content, pH and total chlorophyll were evaluated from fresh leaves; values obtained were used to calculate APTI. Pollutants and metrological parameters were determined using standard methods and weather equipment; validated with LaMotte air-sampler for inside-outside BGs AQI during dry (DS) and rainy seasons (RS), obtained values were used for AQI and correlation analysis. Layout plan (LP) was used to design a complete BGS, planting and leaf morphology (LM) plans, based on computer- aided architectural design (CAAD).
The study revealed that:
i. TS of 180 belonging to 25 families (F) were represented in the study areas, LS showed abundant (16F) and rare (9F). FV ranged from 9.71 to 0.94 TS and 8.95 to 0.01 L of good and moderate level of AAQ. Moraceae has the highest numbers of TS (19) accounting for 10.56% LS of TS;
ii. CA of TS in the 6BGs gave percentage clusters of 63%, outliers 37% and TCCI ranged from 3 to 7 and 1 to 2.67 for shade and shelter respectively;
iii. APTI for Mangifera indica has high value of tolerance 29.46 in all the BGs, while sensitive species Ficus bengamina has lowest value 5.91;
iv. DS and RS AQI ranged from of 34.49 to 40.47 and 31.36 to 37.52 (inside BGs) and 84.60 to 96.38 and 74.38 to 84.82 (outside BGs). However, significant difference p≤0.05 existed among the BGs, pollutants and AQI;
v. BGS prototype designed by CAAD ranged from LP, building 9825mm by 19870mm, planting and LM plans for TS family of Apocynaceae, Moraceae, Araucariaceae and Mimosaceae as sensitive species and Anacardaceae, Meliaceae, Annonaceae and Mytaceae as tolerant species.
The study concluded that, TS families of Apocynaceae, Anacardiaceae, Meliaceae, Moraceae, Mimosaceae, Myrtaceae and Araucariaceae out of 25F were good candidates for ESS such as: lichens occurrence, shading, pollutant removal and AQI improvement by BGS. The BGS is therefore, recommended for provision of ESS to the society.
Description
Keywords
INFLUENCE, BOTANICAL, GARDEN STRUCTURE, PLANNING, DESIGN, ECOSYSTEM SERVICES, ATMOSPHERIC, AIR QUALITY