Carbon, Climate, and Energy C R I T I C A L C O N N E C T I O N S F O R A G R I C U L T U R E

Transcription

1 Carbon, Climate, and Energy C R I T I C A L C O N N E C T I O N S F O R A G R I C U L T U R E

2 Contact Information Jerry L. Hatfield Laboratory Director National Laboratory for Agriculture and the Environment 2110 University Blvd Ames, Iowa (fax)

3 The Problem

4 Worldwide Land Area Land Area per Captia (ha) Worldwide Land Availability Year

5 Yield Production Problem Production deficit to meet food needs for population increase Translates to a water deficit since water use curve behaves as Years Water Use

6 Water Requirements Corn Water Use Efficiency Yield (kg ha -1 ) Water deficit need 120 mm more water to grow 300 bu corn Water Use (mm)

7 Soil Water Availability 35 Available Water Content (%) Organic Matter (%) Data Points Sand, AWC = OM Silt Loam, AWC = OM Silty clay loam, AWC = OM Hudson, 1994

8 Our soil resources are being taxed more with the rapidly increasing population, as a result, soil degradation will take place much faster than ever before. Very thin, fragile atmosphere. 7,018,456,957 people } Very thin, fragile soil. Carbon is Critical!

9 ** Soil Biology Team ** The living soil Earthworms, insects and rodents are the most visible components of the living soil team. They work in tandem either soil microorganisms and fungi to contribute to aeration and nutrient cycling as part of a soil factory team effort.

10 CONSERVATION-TILLED farm fields consume ~4.6 tons of organic matter under the surface of every acre each year. That microbial action is the equivalent of grazing two African elephants per acre, Source: Jerry Hatfield, the director of USDA s National Laboratory for Agriculture and the Environment in Ames, Iowa.

11 The living soil, a biological system. Mammals - gophers, moles, mice, groundhogs Earthworms - night crawlers, garden worms Insects and mollusks - ants, beetles, centipedes, snails, slugs Microfauna - nematodes, protozoa, rotifers Microflora - fungi, yeast, molds, mychorhiza Actinomycetes - smaller than fungi, act like bacteria Bacteria - autotrophs, heterotrophs, rhizobia, nitrobacter Algae - green, blue-green Earthworms, insects and rodents are nature s plow and the most visible components of the living soil team. They work in tandem with other soil fauna, soil microorganisms and fungi to contribute to aeration and nutrient cycling as part of a soil factory team effort.

12 Tillage creates a battle field for the soil biology that is trying to help. Source: Ann Fischer, NRCS, Baker, MT

13 Crop residue benefits Simple crop residue on the surface Feeding the complex soil biology working hard for you below the surface.

14 Changing Climate Temperature Precipitation Carbon dioxide

15 Carbon Dioxide Increases

16 Temperature Changes

17 Temperature Projections

18 Nighttime Temperatures

19 Nighttime Temperatures (Ames) Ames Minimum Temperature - Summer Temperature (F) Summer Temp (June-Aug) Mean Summer Temp Year

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21 Change in Dry Periods and Hot Nights

22 Precipitation Changes

23 Projected Change in N. American Precipitation by

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25 Spring Precipitation (Ames) Ames Spring Precipitation Precipitation (inches) Year Spring Precip (March-May) Mean Spring Precip The increase in spring precipitation has decreased the number of workable field days in April through mid-may across Iowa by 3.5 in 1995 to 2010 compared to

26 12 10 Years having more than 8 days 2 Des Moines Precipitation Days per Year with More than 1.25 inches 2010 through Sept % Increase

27 Soil Erosion 35 Degrading the soil resource decreases the water holding capacity Hudson, 1994 Available Water Content (%) Organic Matter (%) Data Points Sand, AWC = OM Silt Loam, AWC = OM Silty clay loam, AWC = OM

28 Regional Differences in Spring Precipitation

29 US Corn Production

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31 Time - years From Intergovernmental Panel on Climate Change Parallel Hockey Sticks Feb., 2010 CO 2 conc. = 390 ppmv

32 Solar Radiation Carbon Water Nitrogen Soil surface Key Processes Photosynthesis Precipitation N Fixation Respiration Evaporation Mineralization Org Matter decomp Infiltration Denitrification Plant decomposition Runoff Plant decomposition Percolation Cycles interact over time and space with different rates

33 Energy Balance System

34 Plots

35 Study Site Full energy balance and plant growth measurements Measurements throughout the season Coupled Corn water Field and in carbon Central Iowa dioxide measurements

36 14000 Corn on Corn 2009 Kelley Farm Corn Yield Nitrogen Response Yield (kg ha -1 ) Treatment Corn on Soybean Kelley 2009 Yield (kg ha -1 ) Treatment

37 Duration of Photosynthetic Capacity Yield (bu/ac) x x x x x x x10 3 Cumulative PSRI x PAR

38 Light Use Efficiency Light Use Efficiency Spring Strip Fall Chisel Hybrid

39 Iowa County Yields Yield (kg ha -1 ) Cass County Year Observed Corn Yields Maximum Corn Yields Yield (kg ha -1 ) Story County Year Observed Corn Yield Maximum Corn Yield Washington County Yield (kg ha -1 ) Year Observed Corn Yields Maximum Corn Yields Yield (kg ha -1 ) Year Observed Corn Yield Maximum Corn Yield

40 Variation in Yields Iowa County Maize Yields Frequency Cass County Floyd County Story County Washington County Fraction of Potential Maize Yield The majority of the yield losses due to the weather are short-term stresses

41 Crop Yield Variation

42 Soil Water Holding Capacity Current State of Agricultural Soils Soil Organic Matter Time since cultivation

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44 CO2 loss (gco2/m2/h) Evaporation (mm/h) 5 4 CO 2 & H 2 O loss from Low vs High Disturbance Drills CO2 loss Evaporation None Low High Disturbance Type 0 0

45 Soil Water Use Rates 600 C orn W ater U se 2000 W ater U se (m m ) C larion S pring N (100 kg/ha) W ebster S pring N (100 kg/ha) C larion Fall N (200 kg/ha) W ebster Fall N (200 kg/ha) D ay of Y ear

46 Soil Water Availability 35 Available Water Content (%) Organic Matter (%) Data Points Sand, AWC = OM Silt Loam, AWC = OM Silty clay loam, AWC = OM Hudson, 1994

47 No till benefits Virtually all the benefits of no till come from the continuous protective blanket of crop residue or biomass. and not from the lack of soil disturbance by tillage. Credit: Rolf Derpsch

48 Passive protective blanket Active protective blanket

49 Carbon, Climate, Energy Agricultural systems represent the interaction of carbon and energy dynamics Sustainable systems will have to be able to cope with a rapidly changing climate One key to resilient cropping systems is to improve the soil for both erosion protection along with water storage capacity Managing our soils as part of the cropping system will increase the efficiency of water, light, and nutrient use.