Title page for ETD etd-11022011-164027


Type of Document Dissertation
Author Borst, Steven Michael
Author's Email Address sborst@tigers.lsu.edu
URN etd-11022011-164027
Title Influence of Turfgrass Coverage on Nutrient and Pesticide Transport as Affected by Water and Sediment Displacement during Surface Runoff
Degree Doctor of Philosophy (Ph.D.)
Department Horticulture
Advisory Committee
Advisor Name Title
Beasley, Jeffrey Committee Chair
Gambrell, Robert Committee Member
Kuehny, Jeff Committee Member
Sheffield, Ron Committee Member
Strahan, Ron Committee Member
Longstreth, David Dean's Representative
Keywords
  • metolachlor
  • MSMA
  • simazine
  • atrazine
  • herbicide
  • nitrogen
  • phosphorus
  • pendimethalin
  • azoxystrobin
Date of Defense 2011-10-28
Availability unrestricted
Abstract
Turfgrass systems such as roadsides, home lawns, and golf course roughs can vary in surface coverage. Nutrient and pesticide applications applied to these systems may pose an increased risk to adjacent water supplies from surface runoff. Therefore the objectives of this research were: 1) determine the effect surface coverage has on nutrient, pesticide, and sediment runoff and, 2) evaluate the impact of pesticide solubility on runoff losses at varying turfgrass coverages. Surface runoff research commenced in 2010 and 2011 with experimental units consisting of six turfgrass coverages (0, 25, 50, 75, and 100%) and untreated bare soil. Coverages each received a granular fertilizer, atrazine, azoxystrobin, monosodium methyl arsenate (MSMA), pendimethalin, simazine, and S-metolachlor treatment. Simulated rainfall was applied at 7.38 cm hr -1 with runoff collected and analyzed for dissolved nitrogen (DN), total nitrogen (TN), dissolved phosphorus (DP), total phosphorus (TP), total solids (TS) and each pesticide applied. Runoff volumes and TS loading decreased as turfgrass coverage increased from 0 to 100% turfgrass coverage. Total solids decreased from 1078 and 873 kg ha-1 from 0% coverage to 35 and 14 kg ha-1 at 100% turfgrass coverage in 2010 and 2011, respectively. Turfgrass coverage did not affect TN and TP with 5.76 kg N ha-1 and 5.60 kg P ha-1 lost at 100% turfgrass coverage. As turfgrass coverage increased DN and DP losses accounted for greater portions of total losses with decreasing sediment bound nutrients losses. Greater than 56% of DN and DP occurred during the first 15 min after the onset of runoff (AOR). Higher water soluble pesticides were more susceptible to loss during surface runoff. MSMA losses of 25.7% at 100% turfgrass coverage were 7 times greater than the highest pendimethalin losses observed. Similar to soluble nutrients, > 56% of dissolved pesticides were lost in the first 15 min AOR. Total atrazine losses of 12.5 and18.3% compared to total simazine losses of 10.1and 5.7% for 0 and 100% coverage respectively, indicate the importance of maintaining greater turfgrass coverage for reducing sediment bound pollutants. However, turfgrass coverage may not be as effective for reducing dissolved pollutant transport.
Files
  Filename       Size       Approximate Download Time (Hours:Minutes:Seconds) 
 
 28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access 
  borstdiss.pdf 566.02 Kb 00:02:37 00:01:20 00:01:10 00:00:35 00:00:03

Browse All Available ETDs by ( Author | Department )

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