Presentation on theme: "Soil Health Assessment on New York Vegetable Farms"— Presentation transcript:
1Soil Health Assessment on New York Vegetable Farms George Abawi, Dan Brainard, Dan Clune, Kathryn Duhamel, Beth Gugino, Omololu (John) Idowu, Hilary Mayton, Bianca Moebius, Bob Schindelbeck, Janice Thies, Harold van Es, and David Wolfe Departments of Crop and Soil Sciences, Horticulture, and Plant Pathology
2Aspects of Soil Health Inherent soil quality Dynamic soil quality Results from natural soil forming processes and factorsDynamic soil qualityChanges due to human use and managementinteractionThere are two ways to view the quality of soils.(Pierce and Larson, 1993)
3Soil Health and Processes Root proliferation, organismal locomotionAerationWater retentionWater infiltration and transmission; erosion preventionNutrient retention and releaseNP, K, Ca, Mg, etc.micronutrientspHEnergy (C) storageToxicity preventionChemicalPhysicalBiologicalPest suppressionN mineralizationOM decompositionHabitat protection
4How Healthy is a Soil?How to measure?2. Which are meaningful indicators?3. What are appropriate sampling protocols?
5Soil Health Indicators Bulk densityPenetration resistanceAggregate stabilityWater infiltration rateWater holding capacityPore size distribution% OM“Active” C, N in OMCation exchange capacityN, P, KMicronutrients[Toxins, pollutants][Glomalin]ChemicalPhysicalBiologicalSoil disease suppressive capacityBeneficial and pathogenic nematodes, [other pathogens]N mineralization rate (PMN)Decomposition ratemicrobial biomassRespiration rateEarthworm countsGenetic diversity
6Soil health testing procedures must be: RapidInexpensiveScientifically meaningfulAgronomically useful2min
7Our Approach: Research Farm Experiments Commercial Farm Samples Provide scientific basis from controlled trials to establish useful indicatorsCommercial Farm SamplesProvide real-world perspective under range of conditions~700 SAMPLES WERE ANALYZED FOR MULTIPLE POTENTIAL SOIL HEALTH INDICATORS
8Criteria for Selecting Soil Health Indicators Sensitivity to managementFunctional relevanceConsistency and reproducibilityEase (cost) of samplingCost of analysisOpportunity to be estimated by statistical correlation
11Aggregates:Creating and protecting these crumbs keeps the soil open to rain and to air exchange.
12Methodology: Aggregate Stability disturbed samples WSAlg2mm sieve2-8mm aggregatesWSAsm 0.25mm sieve0.25-2mm aggregatesThe Cornell Sprinkler0.5m abovesample aggregates on sievesAggregates beforestability testwettingsoil aggregates1.25cm rainfall in 5 min, providing Energy of 0.142mJ/drop, total of 2.5J/sieve3.5
13Results and Interpretation of Aggregate Stability Test % of Soil crumbs stable to 1.25cm rain/5mins:Organicmanagement~70% - highConventional management~20% - lowCONCLUDE that A.S. can serve as a valuable meaningful easily cheaply measured indicator which can give an indication of on-farm problems.2mm sievesAggregates after stability test
14Soil Pores Aggregate (crumb) Porosity is important for: large poreintermediateporesmall poreAggregate (crumb)Soil PoresPorosity relates to aeration, Water availability, permeability, rootgrowthBiological habitatPorosity is important for:Aeration, permeability, root growthWater availabilityBiological habitat (plant roots and microorganisms)
1613 Year Tillage Experiments 6.5Where wider end of triangle shows which treatment has higher value (so we wouldn’t lose the soil health interpretation part… but then again maybe I just don’t have time to talk about it?)
18Comparison of two NY Vegetable Farms Hamlin Silt LoamUse controlled sites to interpret farm indicator values…
19Roots can be unhealthy due to... Poor soil drainagePoor nutrient availabilitySoil compactionPlant pathogen infection byRhizoctoniaFusariumPythiumThielaviopsisEtc.
20Soil Bioassay w/ Bean for Assessing Soil Health Bean seed planted in field soilBeans grown in greenhouse5 to 6 weeksSoil collectionRoot rot severity rating (1 = healthy to 9 = primary roots rotted)Bean roots are washed
21Root Rot Severity Rating Organic vs Conventional Vegetable Production Systems New York Commercial Vegetable Growers 2004 and 2005GoodModeratePoorNumber of SamplesRoot Rot Severity Rating
22IPM Systems Comparison Site NYSAES, Geneva, NY (C. Petzoldt et al.) Root Rot Severity RatingConventionalOrganicIPM-presentIPM-futureProduction System
23Potentially Mineralizable Nitrogen (PMN) Indicator for: capacity of soil microbes to convert N tied up in complex organic residues into plant-available forms (ammonium and nitrate)Technique: Soil is measured for total N, ammonium-N, nitrate-N at sampling and after a 7-day incubationInterpretation: Positively correlated with %OM, aggregate stability, beneficial nematodes.
24Available or “Active” Carbon (C) Indicator for: Fraction of C and nutrients in total OM that is actually available for soil food web and plants. Shows response to soil mgmt sooner than total OM% changes can be detected.Technique: Measure C in specific OM fractions separated by wet-sieving (shown in photo), or by a more rapid, cheaper colorimetric technique that oxidizes only “active” C.Interpretation: Positively correlated with %OM, and with measures of biological activity
25Weed Seed Bank IndexIndicator for: Weed seed pressure from common broadleaf species and grasses.Technique: Still in “research” phase. Composite soil samples are spread in thin layer in small flats and monitored for 4 weeks for number of selected common broadleaf species, grasses, and “other”. A cold treatment may be used to test for weed species requiring vernalization.Interpretation: Will be primarily useful for tracking a farm over time to see if new practices are effectively reducing the seed bank
26Decomposition RateIndicator for: capacity of soil microbial community to breakdown crop residueTechnique: Moist, sieved soil placed in petri dish with cellulose filter paper; rate of breakdown monitored weekly by counting grid cells degraded, or by digital imaging.Interpretation: Positively correlated with %OM (e.g., muck soils have very high rates), and with other measures of soil biological activity.
27Effect of Cropping System on Selected Soil Health Indicators (2004) TreatmentCropOrg Matter(%)N Min Rate(ugN per g soil per wk)Decomp Rate(% per wk)PlowCorn Grain4.0 b1.48 b3.0 bNo-Till5.4 a1.73 a9.0 aOrganicVeg/rye4.56.1817.0Veg/rye-vetch4.85.7820.0ConvVeg/manure2.320.473.9VegAlfalfa3.061.2010.0
29Timing of Sampling: Does it affect Indicators Values? 7 or 9.5 minYES, for most soil quality indicators.Early spring sampling is recommended.
30Criteria for Selecting Soil Health Indicators Sensitivity to managementFunctional relevanceConsistency and reproducibilityEase (cost) of samplingCost of analysisOpportunity to be estimated by statistical correlation
31Two-Tiered Soil Health Assessment “Standard” soil health test$40-60 per samplebased on disturbed soil samples (with use of sampling ring)includes in-field penetrometer readingsTier 2:Based on purpose and site-specific needsUndisturbed soil samplesHigher and variable cost, with “a la carte” options
32Field Sampling (early spring) TIER 1:10 cores in a bagTIER 1+2:5*4 penetrations, 3 depthsTIER 2:5 cores in rings
33TIER 1 LAB ANALYSES (prices are tentative) VNIR reflectance
34TIER 2 LAB ANALYSES (prices are tentative) VNIR reflectance
38Linking Indicators to Constraints ROOT ROT RATING: SUSCEPTIBILITY TO ROOT DISEASESACTIVE CARBON: ENERGY STORAGE, ABILITY TO SUPPORT SOIL ORGANISMSPOTENTIALLY MINERALIZABLE NITROGEN: ABILITY TO SUPPLY NITROGENAGGREGATE STABILITY: WATER INFILTRATION AND TRANSMISSION; PREVENTION OF RUNOFF AND EROSION; RESISTANCE TO HARDSETTING AND CRUSTING, AERATIONBULK DENSITY: AERATION, ROOT PROLIFERATION, ORGANISM MOBILITYAVAILABLE WATER CAPACITY: WATER STORAGE AND RELEASEPENETROMETER READINGS: SHALLOW AND DEEP ROOT PROLIFERATION, DRAINAGE
39Linking Indicators to Management HIGH ROOT ROT RATING: proper rotation, cover cropsLOW ACTIVE CARBON: cover crops, sod rotation crops, manure, compostLOW POTENTIALLY MINERALIZABLE NITROGEN: add OM, leguminous cover/rotation cropsLOW AGGREGATE STABILITY: reduce tillage, shallow-rooted cover/sod crops, manureHIGH BULK DENSITY: add OM through cover crops, perennial sod crops, manure, compost; limited soil looseningLOW AVAILABLE WATER CAPACITY: add stable OM (compost); reduce tillageHIGH PENETROMETER READINGS: deep tillage/zone building, deep-rooted cover crops
40What’s Next? Develop service lab infrastructure Expand into Northeast Region (NE SARE)Further test methodologies (incl. VNIR)Further develop databaseLink soil health to soil “value”
41Funding Northern New York Agricultural Development Program USDA Northeast Sustainable Agriculture Research and Extension Program (SARE)