Abstract
summary White clover plants ( Trifolium repens L. cv ‘Grasslands Huia’) were exposed to combinations of gaseous pollutants and acid mists similar to those found in many parts of upland Britain. The gaseous pollutant treatments were (a) charcoal‐filtered air (control), (b) SO 2 + NO 2 (c) O 3 and (d) O 3 + SO 2 + NO 2 . The acid mist treatments were 6 mm per week of solutions at pHs of 2.5, 3.5, 4.5 and 5.6. After 12 weeks, canopy reflectance was measured at green, red, near infrared and middle infrared wavelengths using a portable radiometer. Distinct changes in the characteristic spectral reflectance of the clover canopies were noted. The effect of the gaseous pollutants was significant when examined by analysis of variance. The two treatments containing ozone showed particularly marked changes and were statistically separable from the control in a pairwise comparison; the sulphur and nitrogen dioxide treatment was not statistically separable from the control. The acid mists had no significant effect on canopy reflectance. Simple and 4‐waveband vegetation indices showed positive linear relationships with shoot dry weight. The O 3 +SO 2 +NO 2 , in particular, and O 3 treatments produced marked decreases in shoot dry weight and vegetation index. The green and near infrared wavebands were the best discriminators of change in canopy reflectance.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 8
Claim · model-written summary
Gaseous pollutants significantly changed clover canopy reflectance.
- Taxon
- white clover
Trifolium repenst0 - Treatment
- gaseous pollutantse0
- Outcome
- effecte0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“white clover”
e0“The effect of the gaseous pollutants was significant when examined by analysis of variance”
Claim · model-written summary
The two ozone treatments showed marked changes in reflectance relative to control.
- Taxon
- white cloverTrifolium repenst0
- Treatment
- treatments containing ozonee0
- Outcome
- marked changese0
- Comparator
- controle0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“white clover”
e0“The two treatments containing ozone showed particularly marked changes and were statistically separable from the control in a pairwise comparison”
Claim · model-written summary
Sulphur and nitrogen dioxide treatment did not differ significantly from control in reflectance.
- Taxon
- white cloverTrifolium repenst0
- Treatment
- sulphur and nitrogen dioxide treatmente0
- Outcome
- not statistically separablee0
- Comparator
- controle0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“white clover”
e0“the sulphur and nitrogen dioxide treatment was not statistically separable from the control”
Claim · model-written summary
Acid mists had no significant effect on canopy reflectance.
- Taxon
- white cloverTrifolium repenst0
- Treatment
- acid mistse0
- Outcome
- canopy reflectancee0
- Direction
- no significant effecte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“white clover”
e0“The acid mists had no significant effect on canopy reflectance”
Claim · model-written summary
Vegetation indices had positive linear relationships with shoot dry weight.
- Taxon
- white cloverTrifolium repenst0
- Outcome
- shoot dry weighte0
- Direction
- positivee0
- Comparator
- vegetation indicese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“white clover”
e0“Simple and 4‐waveband vegetation indices showed positive linear relationships with shoot dry weight”
Claim · model-written summary
Combined ozone, sulphur dioxide and nitrogen dioxide treatment decreased shoot dry weight and vegetation index.
- Taxon
- white cloverTrifolium repenst0
- Treatment
- O 3 +SO 2 +NO 2e0
- Outcome
- shoot dry weight and vegetation indexe0
- Direction
- decreasese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“white clover”
e0“The O 3 +SO 2 +NO 2 , in particular, and O 3 treatments produced marked decreases in shoot dry weight and vegetation index”
Claim · model-written summary
Ozone treatment decreased shoot dry weight and vegetation index.
- Taxon
- white cloverTrifolium repenst0
- Treatment
- O 3e0
- Outcome
- shoot dry weight and vegetation indexe0
- Direction
- decreasese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“white clover”
e0“The O 3 +SO 2 +NO 2 , in particular, and O 3 treatments produced marked decreases in shoot dry weight and vegetation index”
Claim · model-written summary
Green and near infrared bands best discriminated changes in canopy reflectance.
- Taxon
- white cloverTrifolium repenst0
- Outcome
- change in canopy reflectancee0
- Comparator
- green and near infrared wavebandse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“white clover”
e0“The green and near infrared wavebands were the best discriminators of change in canopy reflectance”
The same questions in other papers
pollution · growth · Trifolium repens (white clover)Results agree
2 papers in the same direction as this paper
- negative
- negative
ozone · growth · Trifolium repens (white clover)Results agree
5 papers in the same direction as this paper
- negative
- negative
- negative
2 papers more in this group
See all 6 papers →Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.