Fig 1.
Photos showing examples of the use of climate screens and shade nets.
Left: a glass greenhouse equipped with climate screens; middle up: a polytunnel during the cooler season; middle down: a polytunnel during the warm season equipped with a shade net; right: a shade house.
Table 1.
Percentage of total photon irradiance (280–900 nm) in each waveband measured outdoors, in a glass greenhouse, and two types of polytunnel.
Table 2.
Different Svensson climate screen samples and their percentage transmittance of integrated total spectral photon irradiance 280–900 nm.
More details about the properties of the screens are given in S1 Table.
Table 3.
Mallas Textiles shade net and insect net samples and their percentage transmittance of integrated total spectral photon irradiance 280–900 nm.
More details about the properties of the nets are given in S2 Table.
Fig 2.
Spectral photon irradiance outdoors, in a glass greenhouse, and two types of polytunnel.
To assist in their comparison, each spectrum is normalized to 1 at the wavelength of its maximum spectral irradiance.
Fig 3.
Spectral photon irradiance under Svensson climate screen samples in ambient sunlight.
(A) Harmony; (B) Luxous; (C) Solaro; (D) Tempa; (E) Insect screens. The orange line in each panel represents the spectrum of full sunlight at the time and location of measurement. To assist in their comparison, each spectrum is normalized to 1 at the wavelength of its maximum spectral irradiance.
Fig 4.
Spectral irradiances under Mallas Textiles shade and insect net samples in ambient sunlight.
(A) Shade net nominal shading factor 90–95; (B) Shade net nominal shading factor 35–80; (C) Patterned shade net nominal shading factor 90; (D) Patterned shade net nominal shading factor 35–80; (E) Insect nets with varying mesh sizes and colours. For the insect nets, AA refers to type Anti-Afidos, AT to Anti-Trip and AI to Anti-Insectos. The orange line in each panel represents the spectrum of full sunlight at the time and location of measurement. To assist in their comparison, each spectrum is normalized to 1 at the wavelength of its maximum spectral irradiance.
Fig 5.
Spectral photon ratios measured in a glass greenhouse and two types of polytunnel.
UVB:PAR is x1000 for ease of comparison. Points are the mean of two measurements. The orange horizontal line in each panel represents the spectral photon ratio of full sunlight at the time and location of measurement.
Fig 6.
Spectral photon ratios measured under Svensson climate and insect screens in ambient sunlight.
UVB:PAR is x1000 for ease of comparison. Points are the mean of two measurements. Nominal shading factors and material type descriptions are taken from manufacturer’s product brochure. The orange horizontal line in each graph represents the spectral photon ratio of full sunlight at the time and location of measurement.
Fig 7.
Spectral photon ratios measured under Mallas Textiles shade nets in ambient sunlight.
UVB:PAR is x1000 for ease of comparison. Points are the mean of two measurements. Nominal shading factors are from the manufacturer’s product brochure. The orange horizontal line in each graph represents the spectral photon ratio of full sunlight at the time and location of measurement.
Fig 8.
Spectral photon ratios measured under Mallas Textiles insect nets in ambient sunlight.
UVB:PAR is x1000 for ease of comparison. Each point is the mean of two measurements. Mesh sizes are taken from manufacturer’s product brochure. The orange horizontal line in each graph represents the spectral photon ratio of full sunlight at the time and location of measurement.