Abstract
There are currently concerns within some sugar industries that long-term monoculture has led to soil degradation and consequent yield decline. An investigation was conducted in Swaziland to assess the effects of fallowing and green manuring practices, over a seven-month period, on sugarcane yields and the physical properties of a poorly draining clay soil. In the subsequent first sugarcane crop after planting, yields were improved from 129 t ha −1 under continuous sugarcane to 141–144 t ha −1 after fallowing and green manuring, but there were no significant responses in the first and second ratoon crops. Also, in the first crop after planting, root length index increased from 3.5 km m −2 under continuous sugarcane to 5.2–6.8 km m −2 after fallowing, and improved rooting was still evident in the first ratoon crop where there had been soil drying during the fallow period. Soil bulk density, total porosity and water-holding capacity were not affected by the fallowing practices. However, air-filled porosity increased from 11 % under continuous sugarcane to 16% after fallowing, and steady state ponded infiltration rates were increased from 0.61 mm h −1 to 1.34 mm h −1 , but these improvements were no longer evident after a year back under sugarcane. Levels of soil organic matter were reduced in all cases, probably as a result of the tillage operations involved. In the plant crop, root length was well correlated with air-filled porosity, indicating the importance of improving belowground air supply for crop production on poorly draining clay soils.
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 11
Claim · model-written summary
Fallowing and green manuring improved first-crop sugarcane yields to 141–144 t ha −1 from 129 t ha −1.
Verbatim
e0“In the subsequent first sugarcane crop after planting, yields were improved from 129 t ha −1 under continuous sugarcane to 141–144 t ha −1 after fallowing and green manuring”
Claim · model-written summary
First and second ratoon yields showed no significant responses.
- Taxon
- SUGARCANEt0
- Organ / stage
- first and second ratoon cropse0
- Treatment
- fallowing and green manuringe1
- Outcome
- responsese0
Not reportedComparatorDirection
Verbatim
e0“but there were no significant responses in the first and second ratoon crops”
e1“after fallowing and green manuring”
t0“SUGARCANE”
Claim · model-written summary
Fallowing increased first-crop root length index to 5.2–6.8 km m −2 from 3.5 km m −2.
Verbatim
e0“root length index increased from 3.5 km m −2 under continuous sugarcane to 5.2–6.8 km m −2 after fallowing”
Claim · model-written summary
Improved rooting persisted in the first ratoon where soil dried during fallowing.
Verbatim
e0“improved rooting was still evident in the first ratoon crop where there had been soil drying during the fallow period”
t0“SUGARCANE”
Claim · model-written summary
Fallowing did not affect soil bulk density, total porosity or water-holding capacity.
- Treatment
- fallowing practicese0
- Outcome
- Soil bulk density, total porosity and water-holding capacitye0
- Direction
- not affectede0
Not reportedTaxonComparator
Verbatim
e0“Soil bulk density, total porosity and water-holding capacity were not affected by the fallowing practices”
Claim · model-written summary
Fallowing increased air-filled porosity from 11 % to 16%.
- Treatment
- fallowinge0
- Outcome
- air-filled porositye0
- Direction
- increasede0
- Value
- 16%e0
- Qualifier
- 11 %e0
- Comparator
- continuous sugarcanee0
Not reportedTaxon
Verbatim
e0“air-filled porosity increased from 11 % under continuous sugarcane to 16% after fallowing”
Claim · model-written summary
Fallowing increased steady state ponded infiltration rates to 1.34 mm h −1 from 0.61 mm h −1.
- Treatment
- fallowinge1
- Outcome
- steady state ponded infiltration ratese0
- Direction
- increasede0
- Value
- 1.34 mm h −1e0
- Qualifier
- 0.61 mm h −1e0
Not reportedTaxonComparator
Verbatim
e0“steady state ponded infiltration rates were increased from 0.61 mm h −1 to 1.34 mm h −1”
e1“to 16% after fallowing”
Claim · model-written summary
Porosity and infiltration improvements disappeared after a year under sugarcane.
Not reportedTaxon
Verbatim
e0“but these improvements were no longer evident after a year back under sugarcane”
Claim · model-written summary
Soil organic matter declined in all cases, probably due to tillage.
- Outcome
- Levels of soil organic mattere0
- Direction
- reducede0
- Qualifier
- probably as a result of the tillage operations involvede0
Not reportedTaxon
Verbatim
e0“Levels of soil organic matter were reduced in all cases, probably as a result of the tillage operations involved”
Claim · model-written summary
Plant-crop root length correlated with air-filled porosity.
Not reportedTreatmentDirection
Verbatim
e0“In the plant crop, root length was well correlated with air-filled porosity”
t0“SUGARCANE”
Claim · model-written summary
The authors emphasize improving belowground air supply for production on poorly draining clay soils.
Verbatim
e0“indicating the importance of improving belowground air supply for crop production on poorly draining clay soils”
t0“SUGARCANE”
The same questions in other papers
rotation · yield · Saccharum officinarum (sugarcane)Positive and negative results
20 papers in the same direction as this paper · 4 in the opposite direction
- no effect
- negative
- no effect
21 papers more in this group
See all 25 papers →fertilization · yield · Saccharum officinarum (sugarcane)Positive and negative results
311 papers in the same direction as this paper · 28 in the opposite direction · 6 reporting no difference from an alternative
- positive
- positive
- no effect
342 papers more in this group
See all 346 papers →rotation · growth · Saccharum officinarum (sugarcane)Results agree
4 papers in the same direction as this paper
- positive
- positive
- positive
1 paper more in this group
See all 5 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.