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1. Development of anammox process for animal waste treatment: experiences in Brazil

Author:
Kunz, Airton; Vanotti, Matias; Szogi, Ariel; Garcia, Mari Cruz; Schierholt Neto, Guilherme Francisco; Soares, Hugo Moreira
Source:
International Symposium on Air Quality and Waste Management for Agriculture : proceedings of the 16-19 September 2007 conference, Broomfield, Colorado pp. -
Subject:
wastewater treatment; animal manure management; anaerobic conditions; ammonia; oxidation; immobilized cells; bacteria; nitrogen; nitrification; denitrification; swine; waste lagoons; sediments; biomass; duration; resins; bioreactors; pig manure; Brazil
Abstract:
... The isolation of anaerobic ammonium oxidation (anammox) bacteria adapted to animal wastewater environments can be of significant importance to farming systems, because excess ammonia in modern, industrial-type livestock production is a global problem, and the use of conventional biological nitrogen (n) removal methods is usually hindered by cost; thus, we think that the more economical anammox bas ...
Handle:
10113/45572

2. Field test of a distributed watershed erosion/sedimentation model

Author:
Smith, R.E.
Source:
Soil erosion : prediction and control : the proceedings of a National Conference on Soil Erosion, May 24-26, 1976, Purdue University, West Lafayette, Indiana. - pp. -
Subject:
sediments; sediment yield; overland flow; equations; infiltration (hydrology); watersheds; soil erosion models; watershed hydrology; hydrologic models; runoff; water erosion; accuracy; soil water movement
Handle:
10113/6410

3. Resources at risk: a fire-based hazard-risk assessment for the Boise National Forest

Author:
Burton, Timothy A.; Dether, Deirdre M.; Erickson, John R.; Frost, Joseph P.; Morelan, Lynette Z.; Rush, William R.; Thornton, John L.; Weiland, Cydney A.; Neuenschwander, Leon F.
Source:
Fire in ecosystem management : shifting the paradigm from suppression to prescription : proceedings of the 20th Tall Timbers Fire Ecology Conference, 7-10, May 1996, Boise Convention Centre "On the Grove", Boise, Idaho, USA / presented by Tall Timbers Research Station ... [et al.] ; [edited by Teresa L. Pruden and Leonard A. Brennan] pp. -
Subject:
coniferous forests; Pinus ponderosa; wildfires; risk assessment; geographic information systems; spatial data; fire regime; models; forest habitats; wildlife habitats; fisheries; forest trees; vegetation structure; watersheds; soil erosion; sediments; forest ecosystems; forest health; Boise National Forest; Idaho
Abstract:
... On the 2.6-million-acre Boise National Forest (NF) in southwestern Idaho, wildfires have burned nearly 50 percent of the ponderosa pine forest over the last nine years. Much of this forest has burned with uncharacteristic intensity. Ponderosa pine forests are now among the most endangered and threatened ecosystems in the U. S. The historic fire regime --- one marked by nonlethal surface fires that ...
Handle:
10113/34403

4. Runoff and erosion on a semi-arid grassland after a wildfire

Author:
Paige, G.B.; Stone, J.J.; Guertin, D.P.; McGee, R.; Blumenfeld, H.
Source:
Second International Wildland Fire Ecology and Fire Management Congress and Fifth Symposium on Fire and Forest Meteorology 16-20 November, Orlando Florida / American Meteorological Society pp. -
Subject:
sediments; sediment yield; canopy; fire ecology; gravelly soils; wildfires; semiarid zones; watersheds; vegetation cover; highlands; rainfall simulation; runoff; water erosion; grasslands; sandy loam soils
Handle:
10113/7601

5. Sediment-Chlorophyll relationship in oxbow Lakes in the Mississippi River Alluvial Plain

Author:
Knight, S.S.; Cullum, R.F.; Welch, T.D.; Cooper, C.M.
Source:
Total maximum daily load (TMDL) environmental regulations : proceedings of 2002 conference pp. -
Subject:
alluvial plains; chlorophyll; lakes; sediments; agricultural runoff; sediment deposition; soil erosion; water quality; phytoplankton; sport fishing; turbidity; nutrients; phosphorus; clay; Mississippi River
Abstract:
... Over the course of the past century, aquatic habitats have declined worldwide, primarily due to draining and clearing for agriculture and urban development. These activities often result in increased erosion and sedimentation with detrimental impacts on stream and lake water quality. It is estimated that 60% of the approximately 3 billion tons of sediment per year deposited in the waterways origin ...
Handle:
10113/47805

6. Small watershed automatic water quality sampler

Author:
Renard, K.G.; Simanton, J.R.; Fancher, C.E.
Source:
Proceedings of the Fourth Federal Interagency Sedimentation Conference : March 24-27, 1986, Las Vegas, Nevada / Subcommittee on Sedimentation, Interagency Advisory Committee on Water Data ; Agricultural Research Service ... [et al.] pp. -
Subject:
sediments; runoff; sediment yield; pollution load; water quality; sampling; samplers; equipment performance; watersheds
Handle:
10113/6411

7. Soil Contributions to Sediment Properties in Walnut Gulch Experimental Watershed: Influence of Slope Factors

Author:
Rhoton, F.E.; Emmerich, W.E.; Goodrich, D.C.; McChesney, D.S.; Miller, S.
Source:
Interagency Conference on Research in the Watersheds [proceedings] pp. -
Subject:
sediments; soil chemical properties; clay fraction; soil organic carbon; semiarid zones; watersheds; soil erosion; erodibility; aggregate stability; soil aggregates; Arizona
Abstract:
... Variations in soil profile thickness, surface soil properties, erosion rates, runoff, and sediment properties within similar soil types and watersheds can generally be explained by slope factors that influence soil erodibility. This study was conducted to determine the effects of surface morphometry on the distribution of watershed soil properties that control erodibility and sediment properties. ...
Handle:
10113/6770

8. Water Quality from Oxbow Lakes within the Mississippi Delta Management Systems Evaluation Area

Author:
Cullum, R.F.; Knight, S.S.; Lizotte, R.E.; Cooper, C.M.
Source:
Total maximum daily load (TMDL) environmental regulations : proceedings of 2002 conference pp. -
Subject:
water quality; lakes; best management practices; drainage; nonpoint source pollution; alluvial plains; sediments; fisheries; phytoplankton; chlorophyll; dissolved oxygen; Mississippi Delta region; Mississippi River; Mississippi
Handle:
10113/47850

9. An overview of Los Alamos research on soil and water processes in arid and semi-arid ecosystems

Author:
Hakonson, T.E.; Lane, L.J.; Foster, G.R.; Nyhan, J.W.
Source:
Erosion on rangelands : emerging technology and data base : proceedings of the Rainfall Simulator Workshop, January 14-15, 1985, Tucson, Arizona / edited by Leonard J. Lane ; [sponsored by U.S. Department of Agriculture, U.S. Department of Energy, Society for Range Management] pp. -
Subject:
sediments; sediment yield; soil water balance; radionuclides; waste disposal; soil pollution; arid lands; spatial distribution; plutonium; particle size distribution; remote sensing; soil erosion; soil transport processes; runoff; rainfall simulation
Handle:
10113/46567

10. A Tube for Studying Dilute Sediments

Author:
Ellington M. Beavers
Source:
Textile research journal 1940 v.10 no.7 pp. 280-286
ISSN:
0040-5175
Subject:
drainage; equations; fabrics; sediments; textile fibers
Abstract:
... 1. The Kelly tube involves an error because of drainage from the side-arm into the main tube, as pointed out by Duncombe and Withrow. 2. It has been shown that this becomes negligible by re- designing the tube. 3. A general equation has been derived which permits direct calculation of the percent settled and which does not require that the density of the particle or the concentration of the suspen ...
DOI:
10.1177/004051754001000703

11. Chemical Determination of Sorbed Water and Structural Hydroxyl in Colloidal Minerals of Soils and Sediments

Author:
E. J. Evans; M. L. Jackson
Source:
Soil Science Society of America journal 1952 v.16 no.4 pp. 364-368
ISSN:
0361-5995
Subject:
heat; ions; methanol; minerals; ovens; sediments; silica; silicates; soil; weight loss
Abstract:
... A method is described for the differentiation of sorbed water from structural hydroxyl ions for colloidal minerals of soils and sediments. It is based on the extraction of the sorbed water (including external surface sorbed and interlayer water) with methanol. The structural hydoxyl is determined by heating the sample in a silica tube oven, passing a gas through the tube, and collection of the lib ...
DOI:
10.2136/sssaj1952.03615995001600040011x

12. Weathering Sequence of Clay-size Minerals in Soils and Sediments

Author:
M. L. Jackson; Y. Hseung; R. B. Corey; E. J. Evans; R. C. Vanden Heuvel
Source:
Soil Science Society of America journal 1952 v.16 no.1 pp. 3-6
ISSN:
0361-5995
Subject:
X-ray diffraction; clay; gibbsite; hematite; hydroxylation; illite; kaolinite; mica; protons; sediments; soil; vermiculite; weathering; China
Abstract:
... Studies were made of several clays of soils and other deposits to clarify the nature of weathering of layer silicates. Data obtained by X-ray diffraction, thermal, R(OH)n sorption, and elemental analyses lead to the proposal of general occurrence of interstratified X-amorphous zones in 2:1 layer silicates. As weathering of true micas proceeds through illite, intermediates, vermiculite, and montmor ...
DOI:
10.2136/sssaj1952.03615995001600010002x

13. Movement of Soluble Salts in Development of Chernozems and Associated Soils

Author:
Ben L. Matzek
Source:
Soil Science Society of America journal 1955 v.19 no.2 pp. 225-229
ISSN:
0361-5995
Subject:
Castanea; Chernozems; calcium carbonate; capillarity; high water table; permeability; salinity; sediments; soluble salts; topography; North Dakota
Abstract:
... In the formation of Chernozem, Chestnut, and associated soils in northwestern North Dakota, translocation of carbonates and other soluble salts takes place. Salts are removed completely from the uppermost 15 to 36 in. of the Chernozem and Chestnut profiles formed from medium-textured till with initial contents of 0.13 to 0.41%. Maximum accumulations of soluble salts may be at depths between 48 and ...
DOI:
10.2136/sssaj1955.03615995001900020030x

14. Field and Laboratory Studies of the Lufkin Soil, a Planosol

Author:
G. W. Kunze; H. Oakes
Source:
Soil Science Society of America journal 1957 v.21 no.3 pp. 330-335
ISSN:
0361-5995
Subject:
A horizons; B horizons; Planosols; cation exchange capacity; clay; clay loam soils; eluviation; exchangeable magnesium; exchangeable sodium; highlands; humid zones; illuviation; magnesium; mineral content; montmorillonite; organic matter; pH; particle size distribution; sediments; soil profiles; subsoil; surface area; texture
Abstract:
... The Lufkin soil is an extreme type of clay pan Planosol found in a warm-temperature humid climate and is developed in moderately clayey sediments of deltaic and marine origin. It occupies mainly, smooth erosional upland with gradients dominantly less than 2%. The solum is composed of a relatively thin A₁ horizon with an erratically developed thin, vesicular A₂ resting abruptly on a dense subsoil o ...
DOI:
10.2136/sssaj1957.03615995002100030021x

15. A Portable Rainfall-Simulator Infiltrometer and Physical Measurements of Soil in Place

Author:
John E. Adams; Don Kirkham; Donald R. Nielsen
Source:
Soil Science Society of America journal 1957 v.21 no.5 pp. 473-477
ISSN:
0361-5995
Subject:
air; corn; crop rotation; glass; infiltration rate; infiltrometers; permeability; rain; runoff; sediments; silt loam soils; soil erosion; surface area; water supply
Abstract:
... A portable rainfall-simulator and infiltration cylinder are described for applying artificial rainfall to soil in place for making infiltration, runoff, and soil erosion measurements. Raindrops are formed by glass capillary tubes protruding through the base of the water supply tank. Each tube has chromel wire suspended in the capillary to reduce the rate of flow. The rainfall is delivered over a c ...
DOI:
10.2136/sssaj1957.03615995002100050004x

16. Constancy of the Sum of Mica Unit Cell Potassium Surface and Interlayer Sorption Surface in Vermiculite-Illite Clays

Author:
O. P. Mehra; M. L. Jackson
Source:
Soil Science Society of America journal 1959 v.23 no.2 pp. 101-105
ISSN:
0361-5995
Subject:
clay; glycerol; gravimetry; illite; kaolinite; mica; montmorillonite; potassium; sediments; soil; sorption; standard deviation; vermiculite; Colorado; Illinois
Abstract:
... The total unit cell planar specific surface was computed as the sum of planar sorption surface (by a glycerol gravimetric method) and the mica unit cell interplanar surface (corresponding to the K). This sum was found to be constant for a given unit cell formula weight, averaging 773 m.²/g. with a standard deviation of ±12.7 or about ±2%. For example, a Colorado vermiculite had 1.63% K₂O equivalen ...
DOI:
10.2136/sssaj1959.03615995002300020007x

17. Equilibrium of Soil Grains at the Threshold of Movement by Wind

Author:
W. S. Chepil
Source:
Soil Science Society of America journal 1959 v.23 no.6 pp. 422-428
ISSN:
0361-5995
Subject:
angle of repose; equations; gravity; sediments; soil; standard deviation; turbulent flow; wind; wind tunnels
Abstract:
... This paper, based on wind tunnel studies, presents an analysis of the nature and magnitude of forces on soil grains at the threshold of their movement by wind. Forces of drag, lift, and gravity were analyzed in relation to each other. The equilibrium between these forces and the soil grains was found to be influenced by the diameter, shape, and immersed density of the grains, the angle of repose ø ...
DOI:
10.2136/sssaj1959.03615995002300060019x

18. Sediment Delivery Ratio Studies in Mississippi. I. A Preliminary Report

Author:
James A. Spraberry; Russell Woodburn; J. Roger McHenry
Source:
Agronomy journal 1960 v.52 no.8 pp. 434-436
ISSN:
0002-1962
Subject:
agronomy; sediments; Mississippi
Abstract:
... SynopsisComputed gross erosion for a number of north Mississippi watersheds was compared with the measured sediment yields. The computed sediment delivery percentages varied greatly for the different watersheds but these differences were not correlated with any measured physical parameter of the watersheds. ...
DOI:
10.2134/agronj1960.00021962005200080002x

19. Characterization of the Sinai Soils

Author:
L. P. Wilding; F. C. Westin
Source:
Soil Science Society of America journal 1961 v.25 no.5 pp. 380-384
ISSN:
0361-5995
Subject:
Chernozems; color; hills; olives; organic carbon; sediments; silty clay loam soils; silty clay soils; total nitrogen; South Dakota
Abstract:
... The Sinai series comprises well-drained Chernozem soils developed in calcareous, finely stratified, glaciolacustrine, silty clay loam and silty clay sediments. These soils occupy the nearly level to gently sloping tops of mesa-like hills interlaced with a more or less continuous, moat-like pattern of colluvial-alluvial drains and swales. The profile has some characteristics of youthful grumusols. ...
DOI:
10.2136/sssaj1961.03615995002500050022x

20. A Classification of ca Horizons in Soils of a Desert Region, Dona Ana County, New Mexico

Author:
Leland H. Gile
Source:
Soil Science Society of America journal 1961 v.25 no.1 pp. 52-61
ISSN:
0361-5995
Subject:
bulk density; calcium carbonate; coatings; compression strength; infiltration rate; mountains; paleosolic soil types; particle size distribution; piedmont; sediments; soil surveys; New Mexico
Abstract:
... A ca horizon is defined in the Soil Survey Manual as an accumulation of calcium carbonate. Field study in Dona Ana County, New Mexico shows that ca horizons occur in soils on a variety of sediments and geomorphic surfaces. A broad fan piedmont extends from the Rio Grande Valley eastward to the igneous Organ Mountains. To the north there is a desert bolson. In soils on these surfaces and in paleoso ...
DOI:
10.2136/sssaj1961.03615995002500010024x