Gupta Gyan Prakash, Singh Sudha, Kumar Bablu, Kulshrestha U C
School of Environmental Sciences, Jawaharlal Nehru University, Delhi, 110067, India.
Environ Monit Assess. 2015 Mar;187(3):67. doi: 10.1007/s10661-015-4301-4. Epub 2015 Feb 3.
Abundance of CaCO3 rich soil dust is a typical feature of atmospheric environment in the Indian region. During prevailing dry weather conditions, dustfall is deposited onto the foliar surfaces of plant affecting their morphology, stomata and the levels of biochemical constituents. This study reports the chemical characteristics of dustfall, its effect on foliar morphology and biochemical constituents of a medicinal plant (Morus alba) at two sites which are differentiated on the basis of landuse pattern, viz., (i) residential, Jawaharlal Nehru University (JNU), and (ii) industrial, Sahibabad (SB), located in the National Capital Region (NCR) of Delhi. Dustfall was characterized for major anions (F(-), Cl(-), NO3 (-) and SO4 (--)) and cations (Na(+), NH4 (+), K(+), Mg(++) and Ca(++)). Biochemical parameters such as chlorophyll a, chlorophyll b, total chlorophyll, carotenoid, proline and ascorbic acid were determined in foliar samples. The results showed that the dustfall fluxes of all the major ions were found to be higher at the industrial site (SB) as compared to the residential site (JNU). Foliar analysis revealed that the levels of biochemical parameters were more affected at SB site due to higher levels of dust SO4 (--) contributed by various anthropogenic sources resulting in more stressful conditions affecting the biochemistry of the plant. The possible entry pathways for dust SO4 (--) into foliar cells are also discussed in the paper. It was noticed that the deposition of urban dust was responsible for the damage of trichome, epidermis, cuticle and stomatal guard cells significantly affecting foliar morphology. SB exhibited more damage to these morphological parts suggesting that industrial dust is harmful to the plants.
富含碳酸钙的土壤尘埃大量存在是印度地区大气环境的一个典型特征。在盛行的干燥天气条件下,降尘会沉积在植物的叶面,影响其形态、气孔以及生化成分的水平。本研究报告了在两个因土地利用模式不同而有差异的地点,即位于德里国家首都辖区(NCR)的(i)居民区,贾瓦哈拉尔·尼赫鲁大学(JNU),和(ii)工业区,萨希巴德(SB),降尘的化学特征、其对一种药用植物(桑树)叶面形态和生化成分的影响。对降尘中的主要阴离子(F(-)、Cl(-)、NO3 (-) 和 SO4 (--))和阳离子(Na(+)、NH4 (+)、K(+)、Mg(++) 和 Ca(++))进行了表征。在叶样中测定了生化参数,如叶绿素 a、叶绿素 b、总叶绿素、类胡萝卜素、脯氨酸和抗坏血酸。结果表明,与居民区(JNU)相比,工业区(SB)所有主要离子的降尘通量更高。叶面分析显示,由于各种人为来源导致的降尘中 SO4 (--) 含量较高,SB 地点的生化参数水平受到的影响更大,从而导致更具压力的条件,影响了植物的生物化学。本文还讨论了尘埃 SO4 (--) 进入叶细胞的可能途径。注意到城市尘埃的沉积导致了毛状体、表皮、角质层和气孔保卫细胞的损伤,显著影响了叶面形态。SB 对这些形态部分的损伤更大,表明工业尘埃对植物有害。