清西陵地区空气负离子分布规律的研究

用ITC-201A型空气负离子测试仪,在清西陵旅游区森林主要生长季节(4-10月份),对清西陵4种典型生境类型—平地针阔混交林、低山丘陵人工林区、丘陵灌草区、河边湿地内空气负离子分布规律及空气负离子与空气温度、相对湿度的关系进行了测定、分析,结果表明:各生境内空气负离子浓度月变化趋势大致相似,均呈双峰型曲线,但各生境间峰值出现时期不同步;清西陵植物生长季节中空气负离子浓度植物生长盛期>植物生长初期>植物生长末期;各生境空气负离子平均浓度值平地针阔混交林>低山丘陵人工林>丘陵灌草区>河边湿地。多数生境春、秋季节空气负离子浓度早8:00、晚18:00较高。午后14:00最低。夏季10:00和16:00时段较高,8:00、14:00及18:00时段较低。空气负离子浓度日变化变异系数春季为0.478、夏季为0.181、秋季为0.150;同一生境不同季节空气负离子浓度日变化幅度不同。空气负离子与空气温度、相对湿度的关系呈三次曲线关系。旱季,空气负离子浓度随空气温度(6～29℃)的升高而降低,空气相对湿度(9%～45%)的增加而升高;雨季,空气负离子浓度随着温度(27～33℃)、相对湿度(46%～70%)的增加均呈先上升后下降的趋势。

Distribution characteristics of negative air ions concentration in area of Qingxiling

The distribution of negative air ions concentration(NAIC)and the relation of it and air temperature,relative humidity in four typical ecological zones(coniferous and broad-leaved mixed stand in plane zone,plantation in hilly mountain shrub,grass stand in hilly zone and riparian wet- land)were measured by using ITC-201A air ion monitor and analyzed in the mainly season of plant growth(4-10 month)in Qing Xi Ling.The results showed that the monthly change of NAIC in different ecological zones were nearly consistent and presented bimodal curve,but the month that ar- rived climax of concentration of air negative ions in different ecological zones was inconsistent.The average concentration of negative air ions of four ecological zones in the order of flouring stage of plant growth>initial stage of plant growth>declining stage of plant growth,the average concentra- tion of negative air ions in entire season of plant growth in every ecological zones were ranked in such order:coniferous and broad～leaved mixed stand in plane zone>plantation in hilly mountain shrub>grass stand in hilly zone>riparian wetland.In spring and autumn,NAIC in the early morning (8:00)and late afternoon(18:00)was higher with lowest in the afternoon(14:00)during a day; in summer,NAIC in the morning(10:00)and afternoon(16:00)was higher with lower with early morning(8:00),mid-day(14:00)and afternoon(18:00).The diurnal coefficient of variation of NAIC in the entire season of plant growth were in the order of spring(0.478)>summer(0.181)>autumn(0.150).The diurnal fluctuation of NAIC in different season in same ecological zone is dif- ferent.The relation of NAIC with air temperature and relative humidity can be simulated by cubic curve model.In dry seasons,NAIC increased as air temperature(6-29℃)decreased and air rela- tive humidity(46 %-70%)increased;NAIC in rainy season showed trends of raising and then de- clining as air temperature(27-33℃)and relative humidity(46 %-70 %)increased.