IOWA NUTRIENT REDUCTION STRATEGY A science and technology-based framework to assess and reduce...
-
Upload
todd-cosgrave -
Category
Documents
-
view
219 -
download
2
Transcript of IOWA NUTRIENT REDUCTION STRATEGY A science and technology-based framework to assess and reduce...
IOWA NUTRIENT REDUCTION STRATEGY
A science and technology-based framework to assess and reduce nutrients to Iowa waters and
the Gulf of Mexico
Spring 2013
1
Why? And Why Now?• Society expects higher environmental actions
from cities, industry and agriculture• Gulf Hypoxia Task Force requires plan to
reduce N and P load to Gulf by 45% by 2013• EPA requests strategy that emphasizes state
implementation of new and existing N and P practices for point and non-point sources
• Pending lawsuit to force EPA to adopt nutrient standards for 31 states of Mississippi River
2
Nutrient Reductions Needed to Meet Gulf of Mexico Hypoxia Goal
Nutrient Reductions• 45% reduction of nitrogen to Gulf• 45% reduction of phosphorus to Gulf
Statewide strategy by 2013 for achieving reductions
3
Nutrient delivery to the Gulf of MexicoState shares of the total nutrient flux
Nitrogen Phosphorus
Alexander et al, Environ. Sci. Techn., in press
4
Science Assessment
For nonpoint source landscapes, to achieve 45% N & P reductions identify– what practices needed– what level of practice adoption– what targeted locations for practices– what estimated costs– what resource assistance and programs are
needed
5
Nutrient Reduction Strategy – Science Team
• Matt Helmers – ISU – N Team Lead• Tom Isenhart – ISU – P Team Lead• John Lawrence – ISU• John Sawyer – ISU• Antonio Mallarino – ISU• William Crumpton – ISU• Rick Cruse – ISU• Mike Duffy – ISU• Reid Christianson – ISU• Phil Gassman – ISU• Dean Lemke – IDALS• Shawn Richmond – IDALS
• Jim Baker – IDALS/ISU• Keith Schilling – IDNR• Calvin Wolter – IDNR• Dan Jaynes – USDA-ARS• Mark Tomer – USDA-ARS• John Kovar – USDA-ARS• David James – USDA-ARS• Eric Hurley – USDA-NRCS• Mark David – Univ. of Illinois• Gyles Randall – Univ. of Mn• Katie Flahive - USEPA
6
Science Assessment• Establish baseline – existing conditions
– Major Land Resource Areas used to aggregate conditions• Extensive literature review to assess potential
performance of practices– Outside peer review of science team documents (practice
performance and baseline conditions)• Estimate potential load reductions of implementing
nutrient reduction practices (scenarios)– “Full implementation” and “Combined” scenarios
• Estimate cost of implementation and cost per pound of nitrogen and phosphorus reduction
7
Nitrogen or Phosphorus?
Nitrogen moves primarily as nitrate-N with water
Phosphorus moves primarily with eroded soil
8
Reaching the 45% goal• Point sources achieve maximum biological
removal rate: 4% N and 16% P• Nonpoint source goal becomes 41% N
and 29% P to achieve 45% goal for Iowa• Requires high adoption of full suite of
practices to reach the goal– Not simple– Not impossible
9
Nitrogen Reduction Practices
Practice % Nitrate-N Reduction [Average (Std. Dev.)]
Nitrogen Management
Timing (Fall to spring) 6 (25)Source (Liquid swine
compared to commercial) 4 (11)
Nitrogen Application Rate Depends on starting pointNitrapyrin (N Serve) 9 (19)Cover Crops (Rye) 31 (29)
Land UsePerennial – Land retirement 85 (9)
Living Mulches 41 (16)Extended Rotations 42 (12)
Edge-of-Field
Drainage Water Mgmt. 33 (32)*Shallow Drainage 32 (15)*
Wetlands 52Bioreactors 43 (21)
Buffers 91 (20)**
10
Phosphorus Reduction Practices
Practice % Phosphorus-P Reduction [Average (Std. Dev.)]
Phosphorus Management
Producer does not apply phosphorus until STP drops to
optimal level17 (40)
Source (Liquid swine compared to commercial) 46 (45)
Incorporation 36 (27)
No-till (70% residue) vs. conventional tillage (30%
residue)90 (17)
Cover Crops (Rye) 29 (37)
Land UsePerennial – Land retirement 75 (-)
Pasture 59 (42)Edge-of-Field Buffers 58 (32)
Phosphorus assessment does not include stream bed and bank contribution 11
Summary of Example Scenarios
Initial Investment (million $)
Total EAC* Cost (million $/year)
Statewide Average EAC Costs ($/acre)Name
NCS1 3,218 756 36
NCS3 1,222 1,214 58
NCS8 4,041 77 4
12
Agricultural Nonpoint Sources
• Nutrient impairment is not mainly due to mismanagement of fertilizers and manures, but more to historic changes in land use and hydrology
13
Agricultural Nonpoint Sources
• Nutrient impairment is not mainly due to mismanagement of fertilizers and manures, but more to historic changes in land use and hydrology
• It is unlikely that in-stream phosphorus loading WQ goals will be achieved from only in-field P loading reductions to streams, given in-channel bed and bank erosion and resulting P loads
14
What’s New?
• Nonpoint and point sources integrated plan & working together towards goal
• Nonpoint source science assessment• Harness the collective initiative of Iowa ag
organizations, ag business & farmers• Major cities (102) and industries (46) treat
to remove nutrients• Coordination through water resources
coordinating council (WRCC)15
Goal – Iowa Leader
“As Iowa is a national and global leader in the production of food and renewable fuels, a goal of this strategy is to make Iowa an equal national and global leader in addressing the environmental and conservation needs associated with food and renewable fuels production.”
16
Iowa Strategy Approach – Nonpoint Sources
• Achieve nutrient load reductions through voluntary technology-based actions, while
• Continuing to assess and evaluate nutrient water quality standards
17
22 Nonpoint Source Actions In 8 Categories
1. Watershed prioritization & goals
2. Setting priorities
3. Research & technology
4. Strengthen outreach, education, collaboration
5. Increased public awareness & recognition
6. Funding
7. Accountability & verification measures
8. Public reporting
18
Strategy Implementation
• 12 of 22 nonpoint source action items are underway now through WRCC & agencies
• ISU Extension Outreach 2012-13– Integrated Crop Management Conference –
1000 CCA’s– Pesticide & manure applicator training, Crop
Advantage Series meetings – 26,000 farmers
• Ag landowners, farmers encouraged to evaluate practices, continue adoption
19
Why is Strategy Important?
• Based on sound science in Iowa, for Iowa• Meaningful and measureable progress• Builds on current programs and targeted
watersheds • Utilizes the policy framework which will
provide greatest progress and success• Improves water quality in Iowa and Gulf of
Mexico
20
www.nutrientstrategy.iastate.edu
Iowa Department of Agriculture and Land Stewardship
www.IowaAgriculture.gov
21