Title page for ETD etd-11152012-160114


Type of Document Master's Thesis
Author Anderson, Jason Robert
Author's Email Address janderson@lsu.edu
URN etd-11152012-160114
Title Effects of Seeding Rates of Perennial Ryegrass (Lolium perenne L.) on Sediment Loading and Nutrient Transport via Surface Runoff
Degree Master of Science (M.S.)
Department Agronomy & Environmental Management
Advisory Committee
Advisor Name Title
Beasley, Jeffery Committee Chair
Bush, Edward Committee Member
Johnson, Charlie Committee Member
Strahan, Ron Committee Member
Keywords
  • sediment loading
  • perennial ryegrass seeding rates
  • surface runoff
  • nutrient transport
Date of Defense 2012-10-29
Availability unrestricted
Abstract
Sediment loading and nutrient losses from construction sites through surface runoff can have detrimental effects on nearby water bodies. Often cool-season grasses such as perennial ryegrass (Lolium perenne L.) are established for temporary coverage until environmental conditions are suitable for warm-season grass establishment. The purpose of this research was to 1) determine if higher seeding rates accelerate establishment thus reducing sediment loading and 2) determine if watering-in fertilizer applications reduces nutrient losses through surface runoff. In the first experiment trays were seeded at 0, 195, 390, or 585 kg ha-1 with 30-min rainfall simulations performed at 16.3 L per minute at 14, 28 and 42 days after seeding (DAS). Increasing seeding rates reduced total sediment loading 48% to 67% and 86% of sediment eroded from bare soil over the 42-day establishment period. Sediment losses were highest during the initial rainfall simulation at 88, 93, 83, and 62% of total sediment lost from 195, 390, or 585 kg ha-1 and bare soil controls, respectively. In the second experiment, established perennial ryegrass was fertilized at 50 kg N ha-1 with grass swards not irrigated or irrigated at 1.25 cm 48 hours prior to rainfall simulation. Thirty-minute rainfall simulations were performed 2 and 7 days after fertilization (DAF). Non-irrigated fertilizer treatments resulted in the highest TKN losses of 12.3 kg N ha-1, moderate dissolved N losses at 3.1 mg N ha-1, and highest TP losses of 2.4 P ha-1 2 DAF compared to 7.0 kg TKN ha-1, 5.2 kg DN ha-1, and 2.0 kg TP ha-1 for irrigated fertilizer treatments. At 7 DAF, iIrrigated fertilizer treatments resulted in higher dissolved N losses of 3.1 kg N ha-1 compared to 0.1 kg N ha-1 for non-irrigated treatments but similar TKN and TP losses of 0.8 kg N ha-1 and 0.4 kg P ha-1 compared to 0.9 kg N ha-1 and 0.2 kg P ha-1 lost from non-irrigated treatments. The two experiments showed increasing perennial ryegrass seeding rates during establishment can significantly reduce sediment losses; while irrigating post N fertilization of established swards may not reduce N losses during surface runoff.

Files
  Filename       Size       Approximate Download Time (Hours:Minutes:Seconds) 
 
 28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access 
  AndersonThesis.pdf 750.14 Kb 00:03:28 00:01:47 00:01:33 00:00:46 00:00:04

Browse All Available ETDs by ( Author | Department )

If you have questions or technical problems, please Contact LSU-ETD Support.