Pengaruh jenis vegetasi dan suhu lingkungan terhadap penyerapan polutan gas NO2

Abstract

Jalur hijau jalan selain memberikan nilai estetik, juga dapat meningkatkan kualitas lingkungan. Keberadaan jalur hijau jalan saat ini, khususnya di daerah perkotaan menunjukkan kearah penurunan kualitasnya. Hal ini seiring dengan meningkatnya pembangunan fisik di perkotaan, seperti pembangunan infrastruktur, permukiman, perdagangan serta industri dan transportasi. Pembangunan pada dasarnya mempunyai dampak yang positif dan negatif bagi manusia dan lingkungannya. Dampak negatif yang mulai dirasakan adalah menurunnya kualitas lingkungan hidup. Salah satu adanya penurunan kualitas lingkungan hidup tersebut adalah timbulnya masalah pencemaran air, tanah dan udara. Pencemaran udara yang terjadi di perkotaan merupakan suatu masalah penurunan kualitas lingkungan hidup yang memerlukan penanganan yang cukup serius. Untuk mengatasi masalah pencemaran udara antara lain telah ditempuh dengan cara pengembangan ruang terbuka hijau (RTH).

Street side green belt giving an esthetics value and increasing environmental quality. However existence of street side green belt in Indonesia, especially in urban area shows toward degradation of their quality. This thing caused by increasing of construction in urban, such as; infrastructure, settlement, commerce and industrial activity and transportation. Negative impact of construction in urban area is lowering of the environmental quality. The real form of degradation environmental quality is incidence of environmental contamination problem like ; water, soil and air pollution. Pollution problem can be reduced through by revegetation of town or urban forest. Plant can lessen pollution problem around the street through absorbtion of gas pollutant and adsorption of particle at leaf surface. To measure absorption of NO2 gas pollutant by plant of leguminoseae/fabaceae exposure to gas 15NO2 in gas chamber. Plant is exposured by gas during 60 minutes at concentration of 3 ppm ( v/v). Exposure treatment conducted at condition of temperature 30°C and 20°C, light intensity 1000 luxes and relative humidity of 60% twice replication. Plant species were exposured consisted of : flamboyan, asam jawa, petai, lamtoro, sengon, saga pohon, kaliandra and gamal. After plant were treated with gas 15NO2 , parts of plant cut and disjointed between roots, bar and leaf. After dried at temperature 80°C during 48 hours, every part of the plant were milled to be smooth. Total nitrogen content is analysed with kjeldahl method. After sample is prepared in the form of liquid, abundance 15N is analysed with spectrometer emission (NOI-6PC Analyzer). Result of research shows level of 15N absorption varied. Among 8 plant absorption ranged from 18,96 μg/g - 44,98 μg/g at temperature 30°C and from 13,90 μg/g - 26,99 μg/g at temperature 20°C. Plants which have the highest absorption is petai ( 44,98 μ g/g) and the lowest is flamboyan ( 13,90 μ g/g). Species that having highest level absorption suggested to be utilized in street side landscape plants functioned to lessen air pollution, especially gas NO2. stomata size has a positive correlation to absorption of gas 15N at both temperature, while respiration rate has a positive correlation to absorption rate on temperature of 30ºC and doesn't has an effect at temperature 20ºC. Absorption of NO2 is higher on 30ºC, than on 20ºC.