public marks

PUBLIC MARKS from paleorthid with tag pedology

December 2006

transect points: Invasive Earthworms

Research shows that invasive earthworms are damaging forest soils and are a menace to species diversity. The problem is most often associated with formerly glaciated regions, where native populations of earthworms are not present. Comparing soil in front of the invaders to post invasion conditions demonstrates that these worms cause soil compaction, reduced soil fertility, and increased erosion. It appears that these invaders are capable of alterations deep enough into the soil profile to result in a change in soil taxonomic classification at the order level. Other concerns are damage to rhizosphere functions, impairing soil carbon sequestration capacity.

March 2006

Soil Taxonomy Forum

Ever wonder how long it takes to form a paleargid in Wyoming? Ask your soil genesis and morphology questions here and get an answer.

transect points: Missoula Soil Science Consultant Speaks

Tell someone you are a soil scientist and it invariably requires an explanation of what you do. It's interesting that few of us do the same things and the telling of it reveals much about the person as well as the community they serve. For that reason I like to collect other folks' descriptions of their work. Certainly the telling of Barry Dutton's life work stands among my favorites because he built his business from scratch in a particularly cost-conscious region. He did it largely without the benefit of the 2 main drivers of regional soil consulting booms: booming suburban sprawl and booming energy prices driving increased well drilling and surface mining for coal and oil shale. I've heard several iterations of Barry's telling over the years and look forward to future installments.

February 2006

CiteULike: Ameliorating physical and chemical properties of highly weathered soils in the tropics with charcoal – a review

Rapid turnover of organic matter leads to a low efficiency of organic fertilizers applied to increase and sequester C in soils of the humid tropics. Charcoal was reported to be responsible for high soil organic matter contents and soil fertility of anthropogenic soils (Terra Preta) found in central Amazonia. Therefore, we reviewed the available information about the physical and chemical properties of charcoal as affected by different combustion procedures, and the effects of its application in agricultural fields on nutrient retention and crop production. Higher nutrient retention and nutrient availability were found after charcoal additions to soil, related to higher exchange capacity, surface area and direct nutrient additions. Higher charring temperatures generally improved exchange properties and surface area of the charcoal. Additionally, charcoal is relatively recalcitrant and can therefore be used as a long-term sink for atmospheric CO2. Several aspects of a charcoal management system remain unclear, such as the role of microorganisms in oxidizing charcoal surfaces and releasing nutrients and the possibilities to improve charcoal properties during production under field conditions. Several research needs were identified, such as field testing of charcoal production in tropical agroecosystems, the investigation of surface properties of the carbonized materials in the soil environment, and the evaluation of the agronomic and economic effectiveness of soil management with charcoal.