Microclimate under different shading screens in greenhouses cultivated with bromeliads

Revista Brasileira de Engenharia Agrícola e Ambiental

Holcman, Ester¹  Sentelhas, Paulo C.² 

[1] USP, Piracicaba;USP

关键词: solar radiation;    air temperature;    protected crops;   

DOI  :  10.1590/S1415-43662012000800007

学科分类：农业科学（综合）

来源: Universidade Federal de Campina Grande * Centro de Ciencias e Tecnologia

【 摘 要 】

This study had as its objective the evaluation of the influence of shading screens of different colors on the different microclimate variables in a greenhouse covered with transparent low-density polyethylene (LDPE). The experiment was conducted with five treatments: thermo-reflective screen (T1); a control - without screen (T2); red screen (T3); blue screen (T4); and black screen (T5), all of them with 70% of shading. An automatic micrometeorological station was installed in each treatment, measuring air temperature (T), relative humidity (RH), incoming solar radiation (Rg), photosynthetically active radiation (PAR) and net radiation (Rn) continuously. The control (T2) and red screen (T3) treatments promoted the highest solar radiation transmissivity, respectively 56.3 and 27%. The black screen (T5) had the lowest solar radiation transmissivity (10.4%). For PAR and Rn the same tendency was observed. The highest temperature was observed under blue screen (T4) treatment, which was 1.3 °C higher than external condition. Blue screen (T4) treatment also presented the highest relative humidity difference between inside and outside conditions.

【 授权许可】

CC BY-NC