Welcome to visit Scientia Silvae Sinicae，Today is

Scientia Silvae Sinicae ›› 2015, Vol. 51 ›› Issue (7): 9-20.doi: 10.11707/j.1001-7488.20150702

Previous Articles     Next Articles

Multi-Scale Comparisons of Particulate Matter and Its Size Fractions Deposited on Leaf Surfaces of Major Greening Tree Species

Wang Huixia1,2, Wang Yanhui1, Yang Jia1,2, Xie Binze1,2, Shi Hui2   

  1. 1. Research Institute of Forest Ecology, Environment and Protection, CAF Beijing 100091;
    2. School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology Xi'an 710055
  • Received:2014-04-03 Revised:2014-11-18 Online:2015-07-25 Published:2015-08-14

PDF (PC)

736

Abstract:

[Objective] Selection of plant species with strong ability to retain pollutants of particulate matters (PM) and its size fractions and suitable for local conditions should be chosen to ensure greening policy be designed to reduce PM pollution. In this study, the amounts of PM and its size fractions (PM2.5, PM>2.5) captured by leaves of twenty-three plant species on the basis of per unit leaf area, per leaf, per plant and per unit green area in the region of Beijing were investigated to find out the appropriate species. [Methods] The amounts of PM (PM2.5, PM>2.5) captured by leaves of twenty-three plant species were examined in this study. The collected leaf samples were washed using a brush with ultrapure water (ELGA, Buckinghamshire, UK) and then filtered through two types of membranes (w1) with pore sizes of 2.5 and 0.1 μm, respectively. Then the membrane with PM (w2) was weighed using balance with an accuracy of 0.1 mg (SI-114, Denver Instrument, USA) after dried at 40℃ for 24 h. The total hemi-surface leaf area (S) was measured using Image J software (Version 1.46; National Institutes of Health, Bethesda, MD, USA) after scanning (HP Scanjet 3570c, Japan). The PM (PM2.5 and PM>2.5) retention amounts were calculated as (w2-w1)/S. The PM (PM2.5 and PM>2.5) retention amounts per leaf, per tree and per unit green area were calculated based on the PM (PM2.5 and PM>2.5) retention amount per unit leaf area, single leaf area, and leaf area index (LAI). Data were subjected to ANOVA with multiple comparisons by using SPSS 19 (IBM, USA), with a level of significance at P<0.05. [Results] Leaf PM, PM2.5 and PM>2.5 per unit leaf area differed among species, by 8.6, 9.8, and 10.5 folds, respectively. Leaf PM, PM2.5 and PM>2.5 on the basis of per leaf, per plant and per unit green area also showed significant differences among species. The maximum difference reached up to 239, 198, and 285 (per leaf); 3 600, 4 100 and 3 600 (per plant); 18.3, 20.5 and 18.1 (per unit green area) folds. In general, the PM, PM2.5 and PM>2.5 retention amounts of different life form was in the order of tree > liana > shrub. For the species with different leaf habit, the evergreen species had a higher PM, PM2.5 and PM>2.5 retention amount per unit leaf area than that of deciduous species. However, the PM, PM2.5 and PM>2.5 retention amounts on the basis of per leaf, per plant and per unit green area were on the contrary. Platanus acerifolia, Salix babylonica, Acer truncatum, and Ulmus pumila were efficient species in capturing PM and its size fractions. Pinus tabulaeformis, Cedrus deodara and Buxus megistophylla had a medium ability to accumulate PM and its size fractions. Less efficient species were Berberis thunbergii, Buxus sinica, Ligustrum quihoui. [Conclusions] The amounts of PM and its size fractions captured by leaves on the basis of per unit leaf area, per leaf, per plant and per unit green area all showed significant differences among species. The ranking presented in terms of capturing PM and its size fractions can be used to select species for atmospheric PM pollution removal in the region of Beijing. Since the quantity of PM and its size fractions captured by leaves depends on the PM and its size fractions retention amount per unit leaf area and leaf area index, efficient plant species and plant configuration designs considering different life form and leaf habit can be used to decrease human exposure to the pollutants.

Key words: urban forest, greening species, air quality, particulate matter and its size fractions, leaf area index, leaf retention of particulate matter

CLC Number: