| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
a Agronomy Dep., Purdue Univ., West Lafayette, IN 47907-1150
b Soil and Water Sciences program, Dep. of Environ. Sci., Univ. of California, Riverside, CA 92521-0424
c U.S.D.A.-Forest Service, Klamath National Forest, 1312 Fairlane Rd., Yreka, CA 96097
d U.S.D.A.-Forest Service, Klamath National Forest, Happy Camp Ranger District, Happy Camp, California, 96039
* Corresponding author (bdlee{at}purdue.edu)
Soils formed from serpentinite contain an abundance of Fe, Mn, Cr, Ni, and Mg, and low concentrations of the plant-essential nutrients Ca and K. The resulting vegetation is commonly xeromorphic and characteristically stunted. This study was conducted to (i) determine the spatial distributions of heavy metals and exchangeable cations (Me) in an ultramafic wetland and surrounding landslide terrain, and (ii) to interpret the distributions relative to environmental conditions and pedogenic processes on the component landscape positions. Distributions of dithionite-extractable metals (Md) and Me in surface soils (0–15 cm depth) were assessed by kriging and by landscape units, characteristic landscape position, soils, and vegetation. Abundance of Mes ranked in the following order: Mg > Ca >> K > Mn > Na > Ni. The Ca/Mg ratios range from 0.13 to 3.77 (mean 0.43), with the highest ratios in a landscape unit with nonserpentine metamorphic colluvium over serpentinitic residuum. Exchangeable cations are concentrated within the wetland relative to surrounding terrain. Dithionite-extractable Fe, Mn, and Ni are concentrated in soils on the oxidizing, nonhydric lower landscape positions, near the hydrologic discharge point of the wetland. Chromium and Al are concentrated in the nonhydric upper landscape positions. Due to reducing conditions, the wetland contains low concentrations of Md relative to the surrounding nonhydric terrain. Large vegetation differences between moisture class coupled with moderate vegetation differences between landscape units within the same moisture class, suggest that vegetation occurrence within the study area is controlled primarily by hydrology, and secondarily by elemental conditions.
Abbreviations: e [subscripted], exchangeable cation • d [subscripted], dithionite extracted metal • CEC, cation-exchange capacity • ICP-OES, inductively coupled Ar plasma optical emission spectroscopy
This article has been cited by other articles:
|
|
 |
|
  J. Caillaud, D. Proust, and D. Righi WEATHERING SEQUENCES OF ROCK-FORMING MINERALS IN A SERPENTINITE: INFLUENCE OF MICROSYSTEMS ON CLAY MINERALOGY Clays and Clay Minerals, February 1, 2006; 54(1): 87 - 100. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 D. J. Bain and G. S. Brush Early chromite mining and agricultural clearance: Opportunities for the investigation of agricultural sediment dynamics in the eastern piedmont (USA) Am J Sci, November 1, 2005; 305(9): 957 - 981. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. D. Lee, S. K. Sears, R. C. Graham, C. Amrhein, and H. Vali Secondary Mineral Genesis from Chlorite and Serpentine in an Ultramafic Soil Toposequence Soil Sci. Soc. Am. J., July 1, 2003; 67(4): 1309 - 1317. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| The SCI Journals | Agronomy Journal | Crop Science | |||
| Journal of Natural Resources and Life Sciences Education |
Vadose Zone Journal | ||||
| Journal of Plant Registrations | Journal of Environmental Quality |
The Plant Genome | |||
