4种柳树叶片表面易去除与难去除颗粒物滞纳特征

doi:10.11707/j.1001-7488.20200603

林业科学 ›› 2020, Vol. 56 ›› Issue (6): 26-34.doi: 10.11707/j.1001-7488.20200603

4种柳树叶片表面易去除与难去除颗粒物滞纳特征

张少伟^1,²,岳晨³,詹振枫³,段劼³,曹治国⁴,刘俊祥¹,古琳^1,*

1. 中国林业科学研究院林业研究所国家林业和草原局林木培育重点实验室北京 100091
2. 河南农业职业学院园艺园林学院郑州 451450
3. 北京林业大学省部共建森林培育与保护教育部重点实验室北京 100083
4. 河南师范大学环境学院黄淮水环境污染防治省部共建教育部重点实验室河南省环境污染控制重点实验室新乡 453007

收稿日期:2019-12-06 出版日期:2020-06-25 发布日期:2020-07-17
通讯作者: 古琳
基金资助:
中央级公益性科研院所基本科研业务费专项资金项目(CAFYBB2018SY003);河南省科技攻关项目(162102110090);北京市大学生创新创业训练项目(S201810022010);郑州市2015年度科技发展计划(20150271);中牟县技术研究与开发项目"对不同灌溉技术下的中原地区典型绿化树种滞纳空气颗粒物能力评价及园林应用研究"

Characteristics of Easy and Difficult Removable Particulate Matter Retained by the Leaves of 4 Willow Species

Shaowei Zhang^1,²,Chen Yue³,Zhenfeng Zhan³,Jie Duan³,Zhiguo Cao⁴,Junxiang Liu¹,Lin Gu^1,*

1. Research Institute of Forestry, CAF Key Laboratory of Tree Breeding and Cultivation, National Forestry and Grassland Administration Beijing 100091
2. College of Horticulture and Landscape, Henan Vocational College of Agriculture Zhengzhou 451450
3. Key Laboratory of Silviculture and Conservation of Ministry of Education, Beijing Forestry University Beijing 100083
4. School of Environment, Henan Normal University Key Laboratory for Yellow River and Huaihe River Water Environmental and Pollution Control, Ministry of Education Henan Key Laboratory for Environmental Pollution Control Xinxiang 453007

Received:2019-12-06 Online:2020-06-25 Published:2020-07-17
Contact: Lin Gu

摘要/Abstract

摘要：

目的: 比较不同柳树叶片表面滞纳易去除和难去除颗粒物的质量及粒径分布差异，评价不同种柳树对颗粒物的滞纳特征，以期为进一步提高树木叶片滞纳大气颗粒物的定量评估精度及合理利用柳树进行城市绿化提供科学依据。方法: 以苗圃中3年生旱柳、龙爪柳、垂柳和蒿柳为研究对象，于雨后第7天（降雨量为36 mm）采集树叶样品，经泡洗得到易去除颗粒物，再对叶片进行刷洗和超声波清洗获得难去除颗粒物，称洗脱颗粒物干质量，测定粒径分布，计算易去除（ERP）、难去除（DRP）和总颗粒物（TRP）中各径级颗粒物质量和滞尘效率。结果: 不同柳树叶面的TRP和ERP滞纳量差异显著，其中ERP滞纳量占TRP滞纳量的比例为30%~50%；不同树种间，龙爪柳的ERP滞纳量最高，蒿柳的TRP和DRP滞纳量最高；在ERP和DRP不同粒径质量百分比方面，旱柳中粒径小于10 μm颗粒物的比例均最高，蒿柳中10~100 μm粒径颗粒物的比例最高；ERP的平均粒径大小排序为蒿柳（34.98 μm）>龙爪柳（33.89 μm）>垂柳（31.52 μm）>旱柳（27.81 μm），DRP的平均粒径大小排序为龙爪柳（40.18 μm）>蒿柳（35.34 μm）>垂柳（29.27 μm）>旱柳（28.25 μm）；对于不同粒径颗粒物的绝对滞纳量，龙爪柳叶片对各径级ERP滞纳量均最高，蒿柳叶片对粒径大于10 μm的DRP滞纳量最高，旱柳叶片对粒径小于10 μm的DRP滞纳量均最高；蒿柳叶片对粒径大于10 μm的TRP和DRP滞尘效率最高，旱柳叶片对粒径小于10 μm的TRP和DRP滞尘效率最高，龙爪柳叶片对ERP的滞尘效率最高。结论: 4种柳树叶面难去除颗粒物滞纳量占50%以上。龙爪柳叶面滞纳的颗粒物更新最快，旱柳和垂柳叶面能持久固定小粒径颗粒物，蒿柳叶面对粒径大于10 μm的颗粒物滞纳能力最强。

关键词: 大气颗粒物, 粒径分布, 滞尘能力, 柳树

Abstract:

Objective: The differences of mass and particle size distribution of the easy-or difficult-removable particulate matter (PM) retained by the leaves among 4 willow species were compared to assess the characteristics of particle retention in willows, further to lay a scientific foundation to improve the quantitative assessment accuracy of atmospheric PM and rational use of willow trees in urban greening. Method: Three years old clones of Salix matsudana, S. matsudana f. tortuosa, S. babylonica, and S. viminalis grown in the nursery were investigated, leaf samples were collected 7 days after rain (rainfall=36 mm). Subsequently the easy removal particle matter (ERP) retained on the leaves were obtained by washing, then the washed leaves were furhter brushed and ultrasonic cleaned to acquire the difficult removable particle matter (DRP). Accordingly, the dry mass of these two types of PM was measured, and the corresponding particle size distribution was determined. Based on these data, the mass and retaining efficiency of the diameter-specific particles in ERP, DRP, and total removable particulate matter (TRP) were calculaed. Result: The differences in elution mass of TRP and ERP among willow species were significant, and the proportion of ERP to TRP ranged from 30% to 50%. Among species, S. matsudana f. tortuosa had the highest retention mass of ERP, while S. viminalis could retain the highest mass of TRP and DRP. On the aspects of the proportions of the diameter-specific particles in both ERP and DRP, S. matsudana displayed the highest proportion of PM₁₀, and S. viminalis displayed the highest PM_10-100. The average diameter of ERP changed as S. viminalis (34.98 μm) > S. matsudana f. tortuosa (33.89 μm) > S. babylonica (31.52 μm) > S. matsudana (27.81 μm), while the situation for DRP was S. matsudana f. tortuosa (40.18 μm) > S. viminalis (35.34 μm) > S. babylonica (29.27 μm) > S. matsudana (28.25 μm). For the absolute retention mass of the diameter-specific particles, S. matsudana f. tortuosa exhibited the largest values for each diameter gradient in ERP, and S. viminalis displayed the largest value for particles larger than 10 μm in DRP, while the largest values for the particles less than 10 μm in DRP were found in S. matsudana. S. viminalis exhibited the highest retaining efficiency (RE) for the TRP and DRP larger than 10 μm, and S. matsudana exhibited the highest RE for the TRP and DRP less than 10 μm. Comparing with the above two species, S.matsudana f. tortuosa had the highest RE of ERP. Conclusion: DRP retained by leaves of four willow species was accounted for 50% of TRP. The retention capacity of S. matsudana f. tortuosa updated rapidly, while S. matsudana and S. babylonica were able to fix the absorbed small-sized PM (d ≤ 10 μm) more persistently, on the contrary, S. viminalis had the strongest capacity of retaining the large-sized PM (d> 10 μm).

Key words: atmospheric particulate matter, diameter distribution of the particles, retention capability, willow

中图分类号:

S731.2

张少伟,岳晨,詹振枫,段劼,曹治国,刘俊祥,古琳. 4种柳树叶片表面易去除与难去除颗粒物滞纳特征[J]. 林业科学, 2020, 56(6): 26-34.

Shaowei Zhang,Chen Yue,Zhenfeng Zhan,Jie Duan,Zhiguo Cao,Junxiang Liu,Lin Gu. Characteristics of Easy and Difficult Removable Particulate Matter Retained by the Leaves of 4 Willow Species[J]. Scientia Silvae Sinicae, 2020, 56(6): 26-34.

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柳树种 Willow species	生活型 Life form	树高 Tree height/m	胸径(地径) DBH (ground diameter)/cm	冠幅直径 Crown diameter/m	叶片特征 Leaf characteristics
旱柳 S. matsudana	乔木 Arbor	3.2	5.1	2.7	叶披针形、无毛、下面白色Lanceolate leaves, without tomentum, white on the below side
龙爪柳 S. matsudana f. tortuosa	乔木 Arbor	2.6	4.7	2.4	叶披针形、微反卷、无毛、下面白色Lanceolate and micro-rollback leaves, without tomentum, white on the below side
垂柳 S. babylonica	乔木 Arbor	3.0	4.9	2.6	叶窄披针形、无毛Narrowly lanceolate leaves, without tomentum
蒿柳 S. viminalis	灌木 Shrub	2.3	(7.8)	2.0	叶线状披针形、内卷、下面密丝状长毛Linear lanceolate and involute leaves only with dense tomentum on the below side

颗粒物类型 PM type	颗粒物粒径 Diameter class of PM	滞尘效率 Retention efficiency/(mg· m^-2d^-1)
颗粒物类型 PM type	颗粒物粒径 Diameter class of PM	旱柳 S. matsudana	龙爪柳 S. matsudana f. tortuosa	垂柳 S. babylonica	蒿柳 S. viminalis
TRP	PM₁	10.23	7.20	6.62	3.73
	PM_1-2.5	16.77	12.35	11.17	5.56
	PM_2.5-10	60.94	45.38	42.42	33.34
	PM_10-100	447.37	616.24	453.59	662.11
	TSP	535.31	681.17	513.8	704.74
ERP	PM₁	2.76	4.74	1.19	1.45
	PM_1-2.5	5.01	7.94	2.17	2.30
	PM_2.5-10	20.51	29.70	10.10	13.35
	PM_10-100	182.81	300.07	158.30	246.10
	TSP	211.10	342.45	171.77	263.20
DRP	PM₁	7.47	2.46	5.43	2.28
	PM_1-2.5	11.77	4.41	9.00	3.26
	PM_2.5-10	40.43	15.67	32.32	19.99
	PM_10-100	264.55	316.17	295.28	416.01
	TSP	324.21	338.72	342.03	441.53

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4种柳树叶片表面易去除与难去除颗粒物滞纳特征

Characteristics of Easy and Difficult Removable Particulate Matter Retained by the Leaves of 4 Willow Species

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树种 Tree species	平均粒径 Average diameter/μm
树种 Tree species	ERP	DRP
蒿柳S. viminalis	34.98	35.45
龙爪柳 S. matsudana f. tortuosa	33.89	40.18
垂柳S. babylonica	31.52	29.27
旱柳S. matsudana	27.81	28.25