遮阳网的小气候效应及其对蔬菜生长的影响

Micro-climate effect of sunshading-net and its influence on vegetable growth

在遮阳网覆盖与露地条件下 ,进行不同蔬菜种类的分期播种对比试验 .采用平行观测法 ,较系统地进行小气候和蔬菜生长状况观测 .结合统计分析 ,得到以下主要结论 :( 1)在晴至少云与多云天气条件下 ,遮阳网覆盖能显著降低气温及地温 ,且 0 cm及 10 cm地温降幅大于气温 ;( 2 )在阴雨天气条件下 ,遮阳网覆盖无降温效果 ;( 3)因水气难以散失 ,雨后覆盖遮阳网 ,会造成高温、高湿的小气候条件 ,并会助长病害的蔓延 ;( 4 )无论何种天气条件 ,遮阳网覆盖均会显著削弱太阳辐射 ;( 5)在蔬菜栽培上 ,苗期覆盖遮阳网 ,有减轻病害、保全苗的效果 ;( 6)全生育期覆盖 ,应视品种的耐阴性选用遮光率合适的遮阳网 ,并注意适时揭、盖 。

Under the conditions of sunshading net coverage and open field, the contrast experiments on various vegetable sowing by stages were conducted. By the method of parallel observation, the observation of micro climate and vegetable growth status proceeded systemativcally. According to statistical analysis, conclusions obtained were as follows:(1) under fine and cloudy weather condition, sunshading net could greatly lower air temperature and earth temperature, at 0 and 10 cm blow ground, earth temperature could drop by a greater extent than air temperature; (2) under rainy weather condition, sunshading net had no effect on lowering temperature; (3) when covering sunshading net after rain, the condition of micro climate of hight temperature and humidity would appear, and the diseases would spread as steam couldn't disperse;(4) despite of what weather conditions, covering sunshading net could lower solar radiation; (5) during culturing vegtable, covering sunshading net at seedling stage could lighten diseases and increase seedlings livability; (6) in a whole growth period, sunshading net with appropriate sunshading rate should be selected according to variety shade tolerance, and vegetables must be exposed and covered in time, or covering sunshading net could reduced output because of lack of illumination.