Determination of antibacterial activity of various broad spectrum antibiotics...
Sustainable Nitrogen and Carbon Cycling on Diversified Horticulture Farms
1. Toward Sustainable Nitrogen and
Carbon Cycling on Diversified
Horticulture Farms Serving Community
Food Systems
Krista L. Jacobsen, Debendra Shresta, Department of Horticulture, University of
Kentucky
Ole Wendroth*, Department of Plant and Soil Sciences, University of Kentucky
John Schramski, College of Engineering, University of Georgia
*presenting author
2013-67019-21403
2. Introduction
Project Background & Context
Project overview
Highlights from one of the field experiments
Overview of modeling objectives and goals
3. Background and Context
Small- and medium-scale, diversified farms are important
sources of agricultural products for the local and regional food
movement
Local food purchases are increasingly valued by the public for
perceptions of healthier products due to “freshness,”
conservation of local farm lands, and/or supporting local farmers
(Onozaka et al, 2010)
Horticultural crops are a large part of this market
Fruits, vegetables and nuts were 70% of local food sales in 2007
(Low & Vogel, 2011).
Diversification into horticultural crops serving local markets is a
global trend for small-holder farmers (Weinberger and Lumpkin,
2007), as horticultural crops are typically higher in value per unit
area than cereals (USDA-NASS, 2009)
4. Background and Context
However, much of what we know about C and N cycling in agroecosystems
comes from agronomic systems, less research in horticulture systems (e.g.
West & Post, 2002; Ma & Shaffer, 2001)
Further, production practices are highly variable, with little standard rotation
varying degree of intensity
Example: A lower input
system, with no
supplemental irrigation,
“living mulch” between
rows, and seasonal
production
Example: Green bean
production in a high tunnel
system, with drip
supplemental irrigation,
intense-tillage, in a year-
round production system
5. Project Objectives
Broadly, to improve our understanding of how intensification on diversified
horticulture-based farms influences (1) nitrogen availability, efficiency, and
retention and (2) soil carbon dynamics in labile carbon pools.
6. Project Objectives:
Specifically…
(i) In addition to C and N dynamics, we are also seeking to better understand the net
effects of intensification on whole system C balances using Energy Returned on Energy
Invested (akin to life cycle analysis) approaches.
More on this next year…
7. Project Objectives
Specifically…
(ii) to compare the nitrogen dynamics and key loss pathways in five farming
systems, including four organic systems, representing a gradient of
intensification (characterized by quantity of inputs, and the frequency of tillage
and fallow periods)
8. Project Objectives:
Specifically…
(iii) to identify the sensitivity of a model to measured parameters to describe the key
plant growth and soil processes.
Soil input:
Soil hydraulic properties
Status of soil moisture and
different C- and N-
fractions
Plant input:
Growth status, root
development
10. New RZWQM GHG Submodel (Fang et al., 2015)
N2O emission (N2O_nit) from DAYCENT, fixed proportion of
nitrification (Rnit) modified by a soil water factor (FSW_Nit) (Gillette et
al., 2017) with WFPS as the water-filled pore space
nitNitSWNitnit RFFr _ON_2 _ON 2
04.1
04.14.0
_
WFPS
WFPS
F NitSW
denDenONden RFrON __2 2
New: diffusion factor for taking into account N2O diffusion across
different soil depths.
13. RESULTS
• Temporal stability of CO2 flux
• rank relationship to surface soil water storage
• What are the main drivers of CO2 flux
14. 6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
JUNE 08, 2010
6/1/2010 8/1/2010 10/1/2010 12/1/2010 1/31/2011 4/2/2011 6/2/2011
5
7
9
SWS0-30cm
(cm)
-10
10
30
SOILTEMP.(C)
SWS SOIL TEMP.
CO2 flux Pattern Development and Dependence on Soil Moisture during
one year.
15. 6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
JUNE 08, 2010
6/1/2010 8/1/2010 10/1/2010 12/1/2010 1/31/2011 4/2/2011 6/2/2011
5
7
9
SWS0-30cm
(cm)
-10
10
30
SOILTEMP.(C)
SWS SOIL TEMP.
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
JUNE 21, 2010
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
JULY 06, 2010
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
JULY 19, 2010
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
AUG. 02, 2010
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
AUG. 16, 2010
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
SEP. 02, 2010
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
SEP. 16, 2010
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
SEP. 30, 2010
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
OCT. 15, 2010
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
OCT. 28, 2010
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
NOV. 11, 2010
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
NOV. 25, 2010
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
DEC. 31, 2010
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
JAN. 31, 2011
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
FEB. 15, 2011
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
MAR. 01, 2011
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
MAR. 17, 2011
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
MAR. 28, 2011
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
APR. 13, 2011
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
APR. 28, 2011
6/1/2010 8/31/2010 11/30/2010 3/1/2011 5/31/2011
DATE OF MEASUREMENT
-1.0
-0.5
0.0
0.5
1.0
SPEARMANRANKCORRELATIONrs
qCO2
qCO2 - WS0-30
JUNE 08, 2011
16. Conclusions
GHG fluxes and relevant soil state variables (moisture,
nitrogen) measured over two seasons.
GHG flux behavior locally driven (SWC and T influence gas
flux only on a relative not on an absolute basis).
First steps in modeling N2O fluxes with RZWQM
Next steps:
• model sensitivity to measured soil parameters
• dynamics at different time-scales
Low, S.A., and S. Vogel. 2011. Direct and intermediated marketing of local foods in the United States, ERR-128, U.S. Department of Agriculture, Economic Research Service, November 2011.
Onozaka, Y., G. Nurse, and D.T. McFadden. Local Food Consumers: How motivations and perceptions translate into buying behavior. Choices Magazine 25(1):
Weinberger, K. and T.A. Lumpkin, 2007. Diversification into horticulture and poverty reduction: A research agenda. World Development 35(8):1464-1480.
US Department of Agriculture, National Agriculture Statistics Service, 2009. Census of Agriculture: Volume 1, U.S. Summary and State Reports. November, 2009. http://www.agcensus.usda.gov/Publications/2007/Full_Report/usv1.pdf .
Ma, L., and M.J. Shaffer, 2001. A review of carbon and nitrogen processes in nine U.S. soil nitrogen dynamics models. In: Modeling Carbon and Nitrogen Dynamics for Soil Management. CRC Press, Boca Raton, FL. p. 55-102
West, T.O. and W.M. Post, 2002. Soil organic carbon sequestration rates by tillage and crop rotation: A global data analysis. Soil Science Society of America Journal 66(6): 1930-1946.