Abstract
Picea chihuahuana probably arrived in North America during Cretaceous or earlier times. The Physiography, climate, and forest geography of its present range in the Sierra Madre Occidental of Mexico are described. The forests are cool montane temperate rather than boreal. In the station examined. P. chihuahuana was distributed only on fresh and moist sites. Growth rates both in height and diameter on moist sites exceeded those on the fresh. The culmination point for diameter growth was at 85 years. The mean specific gravity was .347, and differences due to site were not significant. The moist site soils supporting P. chihuahuana differed from the fresh site soils only in having flower pH, Ca, and K levels. Since the sites were closely associated and the parent materials identical, it is assumed that these differences were due to differences in moisture regime. The foliar nutrient concentration of N, P, and K decreased with increasing needle age except that P and K increased markedly in the oldest needles. Conversely, Ca increased with advancing needle age but decreased in the oldest needles. P. chihuahuana shows a remarkable tolerance for high Ca concentration. The associated vegetation of the P. chihuahuana stand was measured on both fresh and moist sites, and significant differences between the plant assemblages of these sites were found. Its present range and pattern of regeneration indicate that P. chihuahuana may not long escape extinction.
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Claims 14
Claim · model-written summary
Picea chihuahuana probably arrived in North America during the Cretaceous or earlier.
- Taxon
- Picea Chihuahuana
Picea chihuahuanat0 - Outcome
- arrived in North Americae0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Picea chihuahuana probably arrived in North America during Cretaceous or earlier times”
t0“Picea Chihuahuana”
Claim · model-written summary
Its forests are cool montane temperate.
- Taxon
- Picea ChihuahuanaPicea chihuahuanat0
- Outcome
- cool montane temperatee0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The forests are cool montane temperate rather than boreal”
t0“Picea Chihuahuana”
Claim · model-written summary
The tree occurred only on fresh and moist sites at the examined station.
- Taxon
- Picea ChihuahuanaPicea chihuahuanat0
- Outcome
- distributed only on fresh and moist sitese0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“P. chihuahuana was distributed only on fresh and moist sites”
t0“Picea Chihuahuana”
Claim · model-written summary
Height and diameter growth was greater on moist than fresh sites.
- Taxon
- Picea ChihuahuanaPicea chihuahuanat0
- Outcome
- Growth rates both in height and diametere0
- Direction
- exceedede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Growth rates both in height and diameter on moist sites exceeded those on the fresh”
t0“Picea Chihuahuana”
Claim · model-written summary
Diameter growth culminated at 85 years.
- Taxon
- Picea ChihuahuanaPicea chihuahuanat0
- Outcome
- culmination point for diameter growthe0
- Value
- 85 yearse0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The culmination point for diameter growth was at 85 years”
t0“Picea Chihuahuana”
Claim · model-written summary
Mean specific gravity was .347.
- Taxon
- Picea ChihuahuanaPicea chihuahuanat0
- Outcome
- mean specific gravitye0
- Value
- .347e0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The mean specific gravity was .347”
t0“Picea Chihuahuana”
Claim · model-written summary
Specific gravity did not differ significantly by site.
- Taxon
- Picea ChihuahuanaPicea chihuahuanat0
- Outcome
- differences due to sitee0
- Direction
- not significante0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“differences due to site were not significant”
t0“Picea Chihuahuana”
Claim · model-written summary
Moist-site soils had lower pH, calcium and potassium than fresh-site soils.
- Taxon
- Picea ChihuahuanaPicea chihuahuanat0
- Outcome
- flower pH, Ca, and K levelse0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The moist site soils supporting P. chihuahuana differed from the fresh site soils only in having flower pH, Ca, and K levels”
t0“Picea Chihuahuana”
Claim · model-written summary
Foliar nitrogen concentration decreased as needle age increased.
- Taxon
- Picea ChihuahuanaPicea chihuahuanat0
- Outcome
- foliar nutrient concentration of Ne0
- Direction
- decreasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The foliar nutrient concentration of N, P, and K decreased with increasing needle age”
t0“Picea Chihuahuana”
Claim · model-written summary
Foliar phosphorus and potassium concentrations decreased with needle age, then increased in the oldest needles.
- Taxon
- Picea ChihuahuanaPicea chihuahuanat0
- Outcome
- P and Ke0
- Direction
- increasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“P and K increased markedly in the oldest needles”
t0“Picea Chihuahuana”
Claim · model-written summary
Foliar calcium increased with needle age, then decreased in oldest needles.
- Taxon
- Picea ChihuahuanaPicea chihuahuanat0
- Outcome
- Cae0
- Direction
- increasede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Ca increased with advancing needle age but decreased in the oldest needles”
t0“Picea Chihuahuana”
Claim · model-written summary
Picea chihuahuana tolerates high calcium concentration.
- Taxon
- Picea ChihuahuanaPicea chihuahuanat0
- Outcome
- tolerance for high Ca concentratione0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“P. chihuahuana shows a remarkable tolerance for high Ca concentration”
t0“Picea Chihuahuana”
Claim · model-written summary
Associated plant assemblages differed significantly between fresh and moist sites.
- Taxon
- Picea ChihuahuanaPicea chihuahuanat0
- Outcome
- plant assemblagese0
- Direction
- differencese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“significant differences between the plant assemblages of these sites were found”
t0“Picea Chihuahuana”
Claim · model-written summary
The present range and regeneration pattern suggest extinction risk.
- Taxon
- Picea ChihuahuanaPicea chihuahuanat0
- Outcome
- may not long escape extinctione0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Its present range and pattern of regeneration indicate that P. chihuahuana may not long escape extinction”
t0“Picea Chihuahuana”