齐齐哈尔市城市森林空气负离子浓度变化规律

Variation Law of Negative Air Ions Concentration in Urban Forests of Qiqihar City

于2015-2017年的5-10月份,采取定位观测研究方法,在齐齐哈尔市城市森林中选取6个固定观测区,包括16种林分类型,在每个林分类型中设置固定观测点,进行逐月连年观测空气负离子浓度、正离子浓度以及空气温度湿度等环境因子,获取有效观测数据18万个;对观测数据系统全面分析,探索城市森林负离子浓度日变化、月变化、季节变化规律及时空分布格局。结果表明:经3 a连续观测,齐齐哈尔市城市森林空气负离子浓度的日变化规律,一般是早晨(06:00-08:00)达到峰值,随后下降,至中午或下午最低,晚上18:00左右再次出现峰值;负离子浓度最高值可达2000个/cm^3左右、最低值在300个/cm^3左右。齐齐哈尔市城市森林中,空气负离子浓度一年中的变化规律,从5月份开始逐月上升,到9月份达到峰值,从10月份开始下降,负离子浓度5月份最低,9月份最高。齐齐哈尔市城市森林各季节空气负离子浓度水平有所不同,秋季空气负离子浓度水平最高,夏季略低于秋季,春季最低。

By the positioning observation in May to October of 2015-2017,six fixed observation areas were selected in the urban forest of Qiqihar City,including 16 types of forest types,and fixed observation points were set in each forest type.Environmental factors such as negative air ions,positive air ions concentration,and temperature and humidity of air were observed month after month,and 180000 effective observation data were obtained.Through comprehensive analysis of the observation data system,the change regularity of diurnal variation,monthly variation and seasonal variation of negative air ions concentration of urban forest and its time-space distribution pattern were explored.After continuous observation for 3 a,the daily variation of negative air ions concentration in Qiqihar urban forests generally reaches the peak value in the morning(06:00-08:00),then decreases,and then decreases to the lowest at noon or afternoon,and reappears around 18:00 at night peak value;the highest value of negative air ions concentration can reach about 2000/cm^3,and the lowest value is about 300/cm^3.In Qiqihar’s urban forests,the negative air ions concentration changes throughout the year,starting from May and reaching a peak in September,and then starting to decline in October.The anion concentration is lowest in May and highest in September.The negative air ions concentration level in Qiqihar urban forest varies from season to season.The negative air ions concentration level is highest in autumn,slightly lower in summer,and lower in spring.