Abstract
ABSTRACT Application of the principle of mass balance shows that nutrient return does not have a simple algebraic relationship with plant uptake. Due to plant uptake exceeding nutrient return, the total soil pool usually experienced nutrient deficits in various extensive systems. Uptake also exceeded return in intensive systems, but import of nutrients offset this so that total soil pools usually had nutrient gains. Per-hectare return of human excreta was considerable in one Asian system but not in another due to the large export of products in the latter. Failure to return human excreta would have resulted in practiced nutrient sources (return plus import) being not much greater than plant uptake, leading to deficits in the total soil pool if natural losses exceeded natural imports by a small amount. The accuracy of data from one of the Asian systems was confirmed by its fit to the equation relating plant uptake and nutrient return. KEYWORDS: Nutrient cyclingextensive agricultural systemnutrient budgetnight soil
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 7
Claim · model-written summary
Nutrient return did not have a simple algebraic relationship with plant uptake.
Not reportedDirection
Verbatim
e0“nutrient return does not have a simple algebraic relationship with plant uptake”
Claim · model-written summary
Plant uptake exceeded nutrient return in extensive systems, producing usual soil nutrient deficits.
Verbatim
e0“plant uptake exceeding nutrient return, the total soil pool usually experienced nutrient deficits in various extensive systems”
Claim · model-written summary
Plant uptake exceeded nutrient return in intensive systems.
Verbatim
e0“Uptake also exceeded return in intensive systems”
t0“Comparison of Nutrient Return and Plant Uptake in Agricultural Systems”
Claim · model-written summary
Nutrient imports offset the deficit in intensive systems and soil pools usually gained nutrients.
Verbatim
e0“import of nutrients offset this so that total soil pools usually had nutrient gains”
t0“Comparison of Nutrient Return and Plant Uptake in Agricultural Systems”
Claim · model-written summary
Per-hectare human excreta return was considerable in one Asian system.
Verbatim
e0“Per-hectare return of human excreta was considerable in one Asian system”
t0“Comparison of Nutrient Return and Plant Uptake in Agricultural Systems”
Claim · model-written summary
Per-hectare human excreta return was not considerable in another Asian system due to product export.
Verbatim
e0“but not in another due to the large export of products in the latter”
t0“Comparison of Nutrient Return and Plant Uptake in Agricultural Systems”
e1“Per-hectare return of human excreta was considerable in one Asian system”
Claim · model-written summary
An Asian system’s data fit the equation relating plant uptake and nutrient return.
Verbatim
e0“accuracy of data from one of the Asian systems was confirmed by its fit to the equation relating plant uptake and nutrient return”