32 research outputs found
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Spring 1979 Conference Issue
Principles of Turfgrass Weed Control Annual Grasses (page 3) Bean-Shape Islands (7) High Protein Food From Grass (8) Forty-Eighth Annual Turf Conference and Third Industrial Show Program (10) Dutch Elm Disease: Perspectives After 60 Years (13) Toro Irrigation Design Seminar (14) Ideas: New and Old (15) More Pesticide Exams (16) Disposal of Pesticides in Massachusetts (18) Moth Controls Nutsedge Weeds (19) New Pesticide Bill (20
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July 1964
Turf and Lawn Grass Association
Better turf through research and Educatio
On whether azimuthal isotropy and alongshelf translational invariance are present in low-frequency acoustic propagation along the New Jersey shelfbreak
Author Posting. 漏 Acoustical Society of America, 2012. This article is posted here by permission of Acoustical Society of America for personal use, not for redistribution. The definitive version was published in Journal of the Acoustical Society of America 131 (2012): 1762-1781, doi:10.1121/1.3672644.To understand the issues associated with the presence (or lack) of azimuthal isotropy and horizontal (along isobath) invariance of low-frequency (center frequencies of 600鈥塇z and 900鈥塇z) acoustic propagation in a shelfbreak environment, a series of experiments were conducted under the Autonomous Wide-Aperture Cluster for Surveillance component of the Shallow Water 2006 experiment. Transmission loss data reported here were from two mobile acoustic sources executing (nearly) circular tracks transmitting to sonobuoy receivers in the circle centers, and from one 12.5鈥塳m alongshelf acoustic track. The circle radii were 7.5鈥塳m. Data are from September 8, 2006. Details of the acoustic and environmental measurements are presented. Simple analytic and computer models are used to assess the variability expected due to the ocean and seabed conditions encountered. A comparison of model results and data is made, which shows preliminary consistency between the data and the models, but also points towards further work that should be undertaken specifically in enlarging the range and frequency parameter space, and in looking at integrated transmission loss.Office of Naval Research Code 32
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1960
Recent Developments Affecting Golf Course Design (page 1) From the Editor (3) Five Year Results (3) Turf Management Club News (4) Quotes from 1960 Seniors (5) Poa annua - - Friend or Foe (6) The Horticulture Show (7) Cartoons (8) Message from the Winter School President of 1960 (10) The Most Outstanding Turf Senior for 1959 (10) The Value of the Proper Use of Lime (11) Summer Placement (12) A Greenhouse on the Golf Course (13) More Opportunities in the Future for the Aggressive Superintendent at Country Clubs (14) Soil, Sawdust and Turfgrass (15) Picture - Senior Stockbridge Turf majors (16) Picture - Freshman Stockbridge Turf majors (17) Susceptibility of Merion Bluegrass to Stripe Smut (18) Bents in the South (19) Picture - Honorary Members of Turf Management Club (20) Picture - Graduates of Winter School for Turf mangers- 1960 (21) Weather - We are Going to Have Weather, Whether or Not - What Should we Expect by O. Tennebaum & R. E. Lautzenheiser (A-1) The Nature of Winter Injury to Plants by Dr. Johnson Parker (A-1) Turf Problems: You Name it and We\u27ve Had It in \u2759 by Alexander Radko ad T.T. Taylor (A-3) Topdressing Experiences with Greens at Century by James Fulwider (A-5) Poa annua - Fairway Rennovation at winged Foot by Sherwood A. Moore (A-6) Winter Problems at Ekwanaok by Paul O\u27Leary (A-8) Progress Through Drainage by Kayem Ovian (A-10) Winter Injury on Home Lawns by Orlando Capizzi (A-12) The Status of Pre-emergence Chemicals for the Control of Crabgrass by Dr. E. Engel (A-12) Turf Nurseries - Establishment, Maintenance & Utilization by Robert Grant (A-14) Soil Compaction by Dr. R. B. Alderfer (A-16) Water Management Practices on Turf Areas by Dr. J.R. Watson (A-18) Getting to Know Your Members by Owen Griffith (A-23) New Trends in Clubhouse Landscaping by Alfred Boicourt (A-26) General Lawn Management (Alternate Session) Conserving Soil for a good Lawn by Dr. William G. Colby (A-27) Fertilizting and Liming by Dr. Joseph Steckel (A-28) Grasses and Grass Mixtures for New England Lawns by Dr. Robert Schery (A-29) The Care and Maintenance of Establishment Lawns by Dr. John R. Davi
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1964
Turf Management Club by John Traynor (page 1) Who Is Superintendent Here by H.E. Frenette (1) Good Turf Can Result from good Sodding (3) Golf Course Superintendent by Edwart Wiacek (4) Picture - Outstanding Senior Prof. Troll Picture - recognition for Blazers St. Andrew\u27s, Scotland by William Hynd (5) Analogy of a Turf Manager by James B. Cole (6) Fish Trouble by Peter A. Langelier and Dennis P. Leger (8) Square Rings by Robert P. McGuire (9) A Different Type of Course by Robert Hall (10) Literature by Pierre Coste (11) Weeds in Golf Course Turf and Their Control by John F. Cornman (A-1) The USe of Liquid Fertilizer by Anthony B. Longo (A-3) Fertilizing a Golf Course Through an Irrigation System by Herbert E. Berg (A-6) The Extent of Winter Injury on Golf Courses by James L. Holmes (A-11) The Problem of Winter Injury by James B. Beard (A-13) Establishing, Maintaining, and Selling Sod for Turf Areas in New England by George F. Stewart (A-20) Problems of Maintaining Turf Around Industrial Grounds by George Moore (A-22) Landscaping Industrial sites by A.W. Boicourt (A-25) Introduction to the panel Discussion on Grasses for Tees and Their Management by Alexander M. Radko (A-28) Building a Golf Tee by Phil Cassidy (A-29) Grasses for Tees and Their Management by Wm. Dest (A-31) Golf Course Tee maintenance by Jim Fulwider (A-32) Tees by F. Thompson (A-33) How to Draw up a Contract by Lawrence D. Rhoades (A-34) My Contract by Lucien E. Duval (A-37) The Golf Car Problem by Geoffrey S. Cornish (A-41) Golf Cars and Turfgrass by Lee Record (A-42) Course Design and Golf Cars by William F. Mitchell (A-42) Golf Cars and the Established Course by Sherwood Moore (A-45) Course Design and Golf Cars by Phil Wogan (a-52) Introduction of Cars to the New Course by M. Ovian (A-56
The fate of nitrogen and phosphorus at the land-sea margin of the North Atlantic Ocean
Five large rivers that discharge on the western North Atlantic continental shelf carry about 45% of the nitrogen (N) and 70% of the phosphorus (P) that others estimate to be the total flux of these elements from the entire North Atlantic watershed, including North, Central and South America, Europe, and Northwest Africa. We estimate that 61 路 109 moles y-1 of N and 20 路 109 moles y-1 of P from the large rivers are buried with sediments in their deltas, and that an equal amount of N and P from the large rivers is lost to the shelf through burial of river sediments that are deposited directly on the continental slope. The effective transport of active N and P from land to the shelf through the very large rivers is thus reduced to 292 路 109 moles y-1 of N and 13 路 109 moles y-1 of P. The remaining riverine fluxes from land must pass through estuaries. An analysis of annual total N and total P budgets for various estuaries around the North Atlantic revealed that the net fractional transport of these nutrients through estuaries to the continental shelf is inversely correlated with the log mean residence time of water in the system. This is consistent with numerous observations of nutrient retention and loss in temperate lakes. Denitrification is the major process responsible for removing N in most estuaries, and the fraction of total N input that is denitrified appears to be directly proportional to the log mean water residence time. In general, we estimate that estuarine processes retain and remove 30-65% of the total N and 10-55% of the total P that would otherwise pass into the coastal ocean. The resulting transport through estuaries to the shelf amounts to 172-335 路 109 moles y-1 of N and 11-19 路 109 moles y-1 of P. These values are similar to the effective contribution from the large rivers that discharge directly on the shelf. For the North Atlantic shelf as a whole, N fluxes from major rivers and estuaries exceed atmospheric deposition by a factor of 3.5-4.7, but this varies widely among regions of the shelf. For example, on the U.S. Atlantic shelf and on the northwest European shelf, atmospheric deposition of N may exceed estuarine exports. Denitrification in shelf sediments exceeds the combined N input from land and atmosphere by a factor of 1.4-2.2. This deficit must be met by a flux of N from the deeper ocean. Burial of organic matter fixed on the shelf removes only a small fraction of the total N and P input (2-12% of N from land and atmosphere; 1-17% of P), but it may be a significant loss for P in the North Sea and some other regions. The removal of N and P in fisheries landings is very small. The gross exchange of N and P between the shelf and the open ocean is much larger than inputs from land and, for the North Atlantic shelf as a whole, it may be much larger than the N and P removed through denitrification, burial, and fisheries. Overall, the North Atlantic continental shelf appears to remove some 700-950 路 109 moles of N each year from the deep ocean and to transport somewhere between 18 and 30 路 109 moles of P to the open sea. If the N and P associated with riverine sediments deposited on the continental slope are included in the total balance, the net flux of N to the shelf is reduced by 60 路 109 moles y-1 and the P flux to the ocean is increased by 20 纬 109 moles y-1. These conclusions are quite tentative, however, because of large uncertainties in our estimates of some important terms in the shelf mass balance