Abstract
Abstract Decline of high elevation red spruce (Picea rubens Sarg.) forests in the northeastern United States has been related to Ca and Mg deficiencies induced by input of air‐borne nitrogenous nutrients into the forest ecosystem. This research investigated the effects of N nutrition on mineral nutrition of red spruce and radish (Raphanus sativus L.), as an indicator plant, grown in acid forest soil. Red spruce and radishes in the greenhouse were treated with complete nutrient solutions with 15 mM N supplied as 0, 3.75, 7.5, 11.25, or 15 mM NH4 + with the remainder being supplied as NO3. Growth of each species was chlorotic and stunted by increased NH4 + in the nutrient solution. Increasing NH4 + from 0 to 15 mM depressed soil pH by about 1 unit (from 4.5 to an average of 3.5). Accumulation of N, K, Ca, and Mg by each species was restricted as the proportion of NH4 + increased, although the magnitude of these restrictions were small. The restrictions in growth were attributed directly to NH4 + toxicity and not to induction of nutrient deficiencies by NH4 +.
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 4
Claim · model-written summary
Increasing NH4 + in the nutrient solution chlorotic and stunted the growth of red spruce and radish.
- Taxon
- Red spruce and radishes
Picea rubens
Raphanus sativuse1 - Treatment
- increased NH4 + in the nutrient solutione2
- Outcome
- Growthe2
- Direction
- stuntede2
- Qualifier
- chlorotice2
- Setting
- greenhousee1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Red spruce and radishes in the greenhouse were treated with complete nutrient solutions with 15 mM N supplied as 0, 3.75, 7.5, 11.25, or 15 mM NH4 + with the remainder being supplied as NO3”
e2“Growth of each species was chlorotic and stunted by increased NH4 + in the nutrient solution”
Claim · model-written summary
Increasing NH4 + from 0 to 15 mM depressed soil pH by about 1 unit, from 4.5 to an average of 3.5.
- Taxon
- Red spruce and radishesPicea rubensRaphanus sativuse1
- Treatment
- Increasing NH4 + from 0 to 15 mMe3
- Outcome
- soil pHe3
- Direction
- depressede3
- Value
- about 1 unite3
- Qualifier
- from 4.5 to an average of 3.5e3
- Setting
- greenhousee1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Red spruce and radishes in the greenhouse were treated with complete nutrient solutions with 15 mM N supplied as 0, 3.75, 7.5, 11.25, or 15 mM NH4 + with the remainder being supplied as NO3”
e3“Increasing NH4 + from 0 to 15 mM depressed soil pH by about 1 unit (from 4.5 to an average of 3.5)”
Claim · model-written summary
Increasing the proportion of NH4 + restricted accumulation of N, K, Ca and Mg in red spruce and radish, with small magnitude.
- Taxon
- Red spruce and radishesPicea rubensRaphanus sativuse1
- Treatment
- proportion of NH4 + increasede4
- Outcome
- Accumulation of N, K, Ca, and Mge4
- Direction
- restrictede4
- Qualifier
- magnitude of these restrictions were smalle4
- Setting
- greenhousee1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Red spruce and radishes in the greenhouse were treated with complete nutrient solutions with 15 mM N supplied as 0, 3.75, 7.5, 11.25, or 15 mM NH4 + with the remainder being supplied as NO3”
e4“Accumulation of N, K, Ca, and Mg by each species was restricted as the proportion of NH4 + increased, although the magnitude of these restrictions were small”
Claim · model-written summary
The growth restriction of red spruce and radish was attributed to NH4 + toxicity rather than nutrient deficiency.
- Taxon
- Red spruce and radishesPicea rubensRaphanus sativuse1
- Outcome
- restrictions in growthe5
- Qualifier
- NH4 + toxicitye5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Red spruce and radishes in the greenhouse were treated with complete nutrient solutions with 15 mM N supplied as 0, 3.75, 7.5, 11.25, or 15 mM NH4 + with the remainder being supplied as NO3”
e5“The restrictions in growth were attributed directly to NH4 + toxicity and not to induction of nutrient deficiencies by NH4 +”
The same questions in other papers
fertilization · growth · Picea rubens (red spruce)Positive and negative results
2 in the opposite direction
- positive
- positive
fertilization · growth · Raphanus sativus (radish)Positive and negative results
20 papers in the same direction as this paper · 90 in the opposite direction
- negative
- positive
- positive
107 papers more in this group
See all 111 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.