Soil and Plant Testing Nutrient Budgets

Transcription

1 SoilCare Managing Soil for Healthy, Resilient, Productive Pastures Soil and Plant Testing Nutrient Budgets Graham Lancaster (Manager Environmental Analysis Laboratory)

2 EAL Background EAL is an independent University - research, teaching and commercial analytical laboratory. Founded around 1992 as self funded analytical facility now 30 staff, $3.5M/yr turnover. NATA and ASPAC quality assurances. Large range of services (water, soil, leaf, compost, hair, fertiliser, etc) - State of the Art equipment.

3 EAL Background (Cont ) Involved with Biological farming for last 20 yrs initially with Elaine Ingham Soil Foodweb Offers innovative services to enable reduced dependence on inorganic fertilisers. SoilCare Soil Health Card dig, look, smell, feel Concept of Graham Shepherd at South West Soils Conference VSA (Visual Soil Assessment) Agriculture a 3 legged stool! Biology, Chemistry and Physics (soil structure).

4 Analytical Chemistry!

5 Benefits of Monitoring Soil/ Leaf WHY test soil? Determine what nutrients are lacking? Determine excessive nutrients. Assess nutrient balance. Relate chemistry to physical characteristics. Directly target fertiliser or compost applications. Soil testing determines the current nutrient status of your farm soils. Leaf testing provides indication of plant nutrient uptake nutrient cycling and access.

6 Soil Nutrients Analyses typically consists of Available, Exchangeable and/or Soluble/ Plant Available Nutrients. The largest store of nutrients in soil is bound and these are the total nutrients both macro and micro. We can test this store but how can we access these nutrients? Biological farming. Soil biology. Large quantity of inorganic fertilisers are unavailable or leached from the soil? The totals can monitor any buildup of bound nutrients.

7 Totals Nutrients TOTAL NUTRIENTS! (includes rock minerals, organic complexes, etc - Inorganic/ Organic Insoluble Fertilisers)! Chemical Binding! EXCHANGEABLE! NUTRIENTS! (attached to clays, organic matter, biologyincludes complex inorganic fertilisers)! Nutrient Biological Release! Traditional Soil Testing! Procedures! (ie. inorganic farming)! Chemical Binding! SOLUBLE / PLANT! AVAILABLE NUTRIENTS! includes soluble Inorganic Fertilisers and Morgan nutrients! Nutrient Biological Release!

8 Soil Composition XRF True Totals Analyses

9 Soil Sampling Guide See guide to representative sample collection. Across a paddock/ terrain. Typically around 10 samples to a composite sample. GPS useful to accurately determine site location. Never mix different soil types or quality (ie. sand/clay or good and poor paddocks). Surface 10cm (or 15cm for tree crops) after removal of surface organic/ grass layer (Ao horizon).

10 Depth Analysis more nutrients! The large differences over depth relate to soil type changes, leaching of nutrients including inorganic fertilisers, compaction horizons, etc. What depth does fertile soil extend? What depth to bedrock or compaction? On your farm, determine depth and lateral movement of crop roots ie. ability of plants to access to water and nutrients. See following example graphs:

11 Potassium Changes with depth Soluble Potassium (ppm) cm 15-60cm 60-90cm Soil 1 Soil 2 Soil 3 Soil 4 Soil 5 Soil 6 Soil 7 Soil 8 Soil 9 Soil 10 Soil 11 Soil Sites/ Depth

12 Phosphorus changes with depth Bray II P (ppm) cm 15-60cm 60-90cm Soil 1 Soil 2 Soil 3 Soil 4 Soil 5 Soil 6 Soil 7 Soil 8 Soil 9 Soil 10 Soil 11 Soil Sites/ Depth

13 Magnesium changes with depth Soluble Mg ppm cm 15-60cm 60-90cm Soil 1 Soil 2 Soil 3 Soil 4 Soil 5 Soil 6 Soil 7 Soil 8 Soil 9 Soil 10 Soil 11 Soil Sites/ Depth

14 Calcium changes with depth ppm Soluble Ca cm 15-60cm 60-90cm Soil 1 Soil 2 Soil 3 Soil 4 Soil 5 Soil 6 Soil 7 Soil 8 Soil 9 Soil 10 Soil 11 Soil Sites/ Depth

15 AVERAGE ABUNDANCE OF ELEMENTS IN THE EARTHS CRUST AND IN THREE COMMON ROCKS (IN PARTS PER MILLION) (10,000ppm = 1%) ELEMENT CRUST GRANITE BASALT (Crusher Dust) SHALE ELEMENT CRUST GRANITE BASALT (Crusher Dust) O 464, , , ,000 Pr Si 282, , , ,000 Sm Al 81,000 77,000 84,000 92,000 Gd Fe 54,000 27,000 86,000 47,000 Dy Ca 41,000 16,000 72,000 25,000 Er Na 24,000 28,000 19,000 9,000 Yb Mg 23,000 4,000 45,000 14,000 Be K 21,000 32,000 8,000 25,000 Cs Ti 5,000 2,100 9,000 4,500 Hf H 1,400 U P 1, , Br Mn 1, , Sn F Ta Ba As Sr Ge S ,500 Mo C ,000 Ho Zr Eu Cl W V Tb Cr Tl Rb Lu Ni Tm Zn Sb Ce I Cu Cd Y Bi La In Nd Ag Co Se Li Hg N Au Sc Nb Ga Pb B Th Reference: Krauskopf, K, Introduction to Geochemistry, McGraw-Hill Internation. SHALE

16 Interpreting Results See example EAL Soil Test results provided. Concept of general guidelines based on soil type (Heavy, Medium, Light, Sandy) whereby type determined by texture and CEC. This is based on the BCSR concept (Basic Cation Saturation Ratio) Another concept - SLAN Sufficiency Level of Available Nutrients. This concept theoretically assumes that the ideal guide for sandy soil should be sufficient nutrients for all soils and crops.

17 EAL Routine Ag Soil Test ROUTINE AGRICULTURAL SOIL ANALYSIS REPORT Job No: No of Samples: Date Supplied: Supplied by: Methods Used Sample 1 Sample 2 Pdk 1 Oats RR11 Landscape EAL Supplier e.g Clay Method Nutrient Units DXXXX/1 RR11 Indicative guidelines only- refer Note 6 Morgan 1 Calcium Sample ID: Crop: Client: Heavy Soil e.g Clay Loam e.g Loam e.g Loamy Sand Ca Mg Inhouse Method S10 - (Based on mg/kg K Morgan 1941) P Bray1 Rayment & Lyons E note 8 30 note 8 24 note 8 20 note 8 Colwell Phosphorus P mg/kg Rayment & Lyons B Bray2 Bray & Kurtz note 8 60 note 8 48 note 8 40 note 8 KCl 1:5 Water Magnesium Potassium Phosphorus Nitrate Nitrogen Ammonium Nitrogen Sulfur ph Conductivity N Inhouse Method S37 - (Based on mg/kg Rayment & Lyons-7C2) S units Rayment & Lyons A ds/m Rayment & Lyons A Calculation Estimated Organic Matter % OM % C x >5.5 >4.5 >3.5 >2.5 Medium Soil Light Soil Sandy Soil Table part 1 of 5 - Soluble Reams Nutrients

18 No of Samples: Date Supplied: Supplied by: Methods Used Sample 1 Sample 2 Pdk 1 Oats RR11 Landscape EAL Supplier e.g Clay Method Nutrient Units DXXXX/1 RR11 Indicative guidelines only- refer Note 6 Ammonium Acetate + Calculations Calcium Magnesium Potassium Sodium KCl Aluminium Al Acidity Titration Hydrogen H + Ca Mg K Na Sample ID: Crop: Client: Heavy Soil e.g Clay Loam e.g Loam e.g Loamy Sand cmol + /Kg kg/ha mg/kg cmol + /Kg kg/ha mg/kg Rayment & Lyons D3 cmol + /Kg kg/ha mg/kg cmol + /Kg kg/ha mg/kg cmol + /Kg kg/ha mg/kg Rayment & Lyons G1 cmol + /Kg kg/ha mg/kg Calculation Effective Cation Exchange Capacity (ECEC) cmol + /Kg Rayment & Lyons J Calcium Magnesium Medium Soil Light Soil Ca Mg Potassium K Base Saturation Calculations % Rayment & Lyons M1 Sodium - ESP Na Aluminium Al Hydrogen H Calculation Calcium / Magnesium Ratio ratio Rayment & Lyons M Sandy Soil Table part 2 of 5 - Exchangeable Cations

19 Job No: No of Samples: Date Supplied: Supplied by: Sample ID: Crop: Client: Methods Used Sample 1 Sample 2 Pdk 1 Oats RR11 Landscape Heavy Soil EAL Supplier e.g Clay Method Nutrient Units DXXXX/1 RR11 Indicative guidelines only- refer Note 6 DTPA CaCl 2 LECO IR Analyser Zinc Manganese Iron Copper Boron Silicon Total Carbon Total Nitrogen Medium Soil e.g Clay Loam Light Soil e.g Loam Sandy Soil e.g Loamy Sand Zn Mn mg/kg Rayment & Lyons A1 Fe Cu B Rayment & Lyons C mg/kg Si Sauer et al C % Rayment & Lyons B2b >3.1 >2.6 >2.0 >1.4 N % Rayment & Lyons A >0.30 >0.25 >0.20 >0.15 Calculation Carbon/ Nitrogen Ratio ratio Rayment & Lyons A Basic Texture Basic Colour Clay Loam Clay Red Dark Brown Calculation Chloride Estimate equiv. ppm Conductivity x #REF! Table part 3 of 5 - Micronutrients, miscellaneous

20 No of Samples: Date Supplied: Supplied by: Sample ID: Methods Used Sample 1 Sample 2 Pdk 1 Oats RR11 Landscape EAL Supplier e.g Clay Method Nutrient Units DXXXX/1 RR11 Indicative guidelines only- refer Note 6 Calcium Ca 1,396 4,480 Magnesium Mg 1,200 1,291 Total Acid Extractable Potassium K mg/kg 2,941 1,274 Sodium Na < Sulfur S 53 <50 Total Acid Extractable Phosphorus P mg/kg 216 4,258 Zinc Zn Manganese Mn Rayment & Lyons F1 based Iron Fe on APHA 3120 ICPOES, USEPA 3050B 14,585 24,466 Total Acid Extractable Copper Cu mg/kg Boron B 3 3 Silicon Si 1, Aluminium Al 10,308 10,403 Molybdenum Mo Total Acid Extractable Cobalt Co mg/kg 5 8 Selenium Se < Cadmium Cd < Lead Pb Arsenic As Total Acid Extractable Chromium Cr mg/kg Nickel Ni Mercury Hg Silver Ag <1 6 Crop: Client: Heavy Soil Medium Soil e.g Clay Loam Light Soil e.g Loam 1,000-10,000 Ca 500-5,000 Mg 200-2,000 K Na 100-1,000 S 400-1,500 P Zn 200-2,000 Mn 1,000-50,000 Fe Cu 2-50 B 1,000-3,000 Si 2,000-50,000 Al Mo 5-50 Co Se < 5 Cd < 75 Pb < 25 As <25 Cr <150 Ni < 3.75 Hg Ag Sandy Soil e.g Loamy Sand Table part 4 of 5 - Totals, contaminants

21 No of Samples: Date Supplied: Supplied by: Sample ID: Crop: Client: Methods Used Sample 1 Sample 2 Pdk 1 Oats RR11 Landscape EAL Supplier e.g Clay Method Nutrient Units DXXXX/1 RR11 Indicative guidelines only- refer Note 6 Water Extractable Chloride Cl mg/kg Rayment & Lyons A2 15 Permanganate Oxidisable Labile Carbon % Blair et al Olsen Phosphorus P mg/kg Rayment & Lyons C2b LECO IR Analyser Total Organic Carbon % C Rayment & Lyons B CaCl 2 ph units Rayment & Lyons B PBI Phosphorus Buffer Index - Uncorrected Index Rayment & Lyons I2b 164 PBI COLWELL Phosphorus Buffer Index - Colwell Corrected Index Rayment & Lyons I2b 206 PCSM Paramagnetism µcgs Phil Callahan Soil Meter <10 BSES Phosphorus P mg/kg Rayment & Lyons G2 403 Walkley & Black Organic Carbon % C Rayment & Lyons A Loveday/Pyle Dispersion Index Index Loveday & Pile 1973 Colwell Potassium mg/kg Rayment & Lyons A Nitric K Potassium cmol+/kg Rayment & Lyons C BSES Silicon mg/kg Rayment & Lyons D2 750 CaCl 2 Silicon mg/kg Haysom & Chapman Northcote Soil Texture Northcote 1979 MCP Sulfate-S mg/kg Rayment & Lyons B KCl-40 Sulfur mg/kg Rayment & Lyons D BSES -HCl Zinc mg/kg Rayment & Lyons D1 6.7 Heavy Soil Medium Soil e.g Clay Loam Light Soil e.g Loam Sandy Soil e.g Loamy Sand Table part 5 of 5 Optional Tests

22 ROUTINE AGRICULTURAL SOIL ANALYSIS REPORT EAL Soil Testing Notes 1. All results presented as a 40 C oven dried weight. Soil sieved and lightly crushed to <2 mm 2. Methods from Rayment and Lyons, Soil Chemical Methods 3. Soluble Salts included in Exchangeable Cations - NO PRE-WASH 4. 'Morgan 1 Extract' adapted from 'Science in Agriculture', 'Non-Toxic Farming' and Lamonte Soil Handbook. 5. Guidelines for phosphorus have been reduced for Australian soils 6. Indicative guidelines are based on 'Albrecht' and 'Reams' concepts 7. Total Acid Extractable Nutrients indicate a store of nutrients 8. Contaminant Guides based on 'Residential with gardens and accessible soil including childrens daycare centres, preschools, primary schools, town houses or villas' (NSW EPA 1998). 9. Information relating to testing colour codes is available on Sheet 2 - " Understanding you soil results" Calculations 1. For conductivity 1 ds/m = 1 ms/cm = 1000 µs/cm 2. 1 cmol + /Kg = 1 meq/100g; 1 Lb/Acre = 2 ppm (parts per million); kg/ha = 2.24 x ppm; mg/kg = ppm 3. Conversions for 1 cmol+/kg = 230 mg/kg Sodium, 390 mg/kg Potassium, 122 mg/kg Magnesium, 200 mg/kg Calcium 4. Organic Matter = %C x Chloride Estimate = EC x 640 (most likely over-estimate) 6. ECEC = sum of the exchangeable cations cmol + /Kg 7. Base saturation calculations = (cation cmol+/kg) /ECEC x Ca / Mg ratio from the exchangeable cmol + /Kg results Quality Checked: Kris Saville Manager, Agricultural testing division

23 Understanding your EAL soil results Soil Acidity - Is the water ph >6.5 or CaCl 2 ph >5.5 hence no major problem. >7pH indicates alkaline soil. Soil with ph below 4.5 often has high kg/ha exchangeable hydrogen and aluminium (and likely high % exchangeable H and Al). Cation Exchange Capacity - Using the ECEC or CEC is the soil heavy, medium, light or sandy? In particular, compare the exchangeable Calcium and Potassium in kg/ha to suggested guidelines. Soil Salinity - Is the electrical conductivity (EC) above texture guidelines (ie. > 0.2dS/m heavy soil) hence indicates possible salinity issue. If the Exchangeable Sodium Percentage or % Exchangeable Sodium > 5% then possible salt issue. With high EC the chloride is also likely to be elevated. Ca/Mg Ratio - Above 5 indicates good soil structure. Ratio 1 5 suggests addition of calcium to assist soil structure. Ratio <1 (ie. far higher magnesium) often indicates high clay soil and possibly a sub-soil. Compaction and poor water infiltration is a likely indication of the cation imbalance. Organic Matter - Refer to guidelines - >5.5% indicates good organic carbon and organic matter in the soil. Total Carbon to Total Nitrogen ratio should be around 12:1 If higher then suggests depletion of organic nitrogen. Phosphorus - Are the levels of Bray I (plant available)/bray II (exchangeable P) below or above the guidelines. At, above or near guidelines suggests no need for P addition. Solubles - Nitrate, ammonium and sulfur compare to guidelines for soil type. Leachable nutrients hence may be further down soil profile. Micronutrients - Plant available Iron, Manganese, Copper and Zinc compare to guidelines to assess if relatively low or high. Iron and manganese availability is significantly influenced by soil ph (acid soils often have very high soluble iron). Leaf testing is ideal for confirming potential issues with micronutrients. Boron - A micronutrient extracted as plant available compare to guidelines but be aware boron is very leachable and could be elevated down the soil profile. Acid Extractable Nutrients - If total available nutrients were analysed then use numbers as a guide to compare to assess store of nutrients.

24 Soil Phosphorus hundreds of methods No of Samples: Date Supplied: Supplied by: Sample ID: Crop: Methods Used/ Method Description Heavy Soil Medium Soil Light Soil Sandy Soil Method Nutrient Client: Units e.g Clay e.g Clay Loam e.g Loam Indicative guidelines only- refer Note 6 e.g Loamy Sand Morgan 1 Phosphorus (Soluble- Plant Available) P mg/kg Inhouse Method S10 - (Based on Morgan 1941) Bray1 Phosphorus (Plant Available in mainly acid to neutral soils) P mg/kg Rayment & Lyons E2 45 note 8 30 note 8 24 note 8 20 note 8 Phosphorus (Plant Available and some residual P in mainly Colwell P mg/kg Rayment & Lyons B acid, neutral or alkaline soils) Phosphorus (Plant Available and favours sorbed plus acidsoluble forms of P in mainly acid to neutral soils) Bray2 P mg/kg Bray & Kurtz note 8 60 note 8 48 note 8 40 note 8 Total Acid Extractable Phosphorus (total acid extractable store of phosphorus but not all the mineral forms of P evident in XRF Analysis) P mg/kg (Based on Rayment & Lyons B1) 400-1,500 P Phosphorus Buffer Index - Colwell Corrected (Characterise PBI COLWELL the P Buffer capacity or P sorptivity or P fixing ability of Index Rayment & Lyons I2b soils - used to assess leaching ability of P from soils) Phosphorus (Intensity component of soil P - readily Olsen Index Rayment & Lyons I2b available) Phosphorus (developed mainly for Sugar Cane in eastern BSES P ppm Rayment & Lyons G2 Coastal QLQ- used to assess the 'avialable P')

25 Soil Nutrient Budgets- Calculations Nutrient budgets typically based on the available/ soluble nutrients and typically based on soil depth of 10-15cm. Another much greater store of nutrients as totals and also with depth. A biological system typically provides an access to these stores. All nutrients can be converted to Kg/ha and hence nutrient inputs from compost/ mulch or organic fertilisers can be calculated (Kg/ha = 2.24 x ppm).

26 Environmental Issues Healthy soils function to: Sustain biological activity Store and cycle water and nutrients Decompose organic matter Inactivate (bind) toxic compounds Suppress pathogens Protect water quality and enhance catchment health A balance exists between optimum soil nutrients for plant growth and nutrient runoff

27 Plant Leaf Testing Sample collection most important often last seasons growth, 3 rd whirl back (refer guide) Total Acid digest hence TOTAL ELEMENT Reproducibility between labs generally very good Bias if samples are collected after foliar application (with no leaf washing). Total analysis of N, P, K, Ca, Mg, Na, S, C, Fe, Mn, Cu, Zn, B and Mo (+ Co, Si)

28 Plant Leaf Testing (Cont ) Leaf testing can be used to design a fertility program but not standard should be in conjunction with soil. Increase fruit production may give bias of lower leaf nutrients Sap analysis dependent on many factors but Brix onsite testing tends to be useful for biological farming - onsite technique using a refractometer and garlic press

29 Brix levels It is a way of measuring the quality of various foods and plants. It is measured using a Refractometer which is a simple optical instrument to measure dissolved solids content of plant sap, as well as the juice from fruits & vegetables. Refractometers measure % Sucrose by weight (Brix). Refractometers have been used extensively in the grape and citrus fruit industries, but are now being used by farmers & consumers everywhere. A higher Brix reading means:! Fruits or vegetables that taste sweeter! Foods that are lower in water content & more minerally nutritious! Crops that show greater resistance to insect damage! Plants that have a significantly lower freezing point & greater resistance to frost damage

30 EAL Totals Plant Leaf Package PLANT LEAF ANALYSIS REPORT XX samples supplied by XXX on XXXX, XXXX - Lab Job No. BXXXX Analysis requested by XXXXX. Sample 1 TOTAL Nutrients (Acid Digest/ Combustion) TOTAL Salts (Acid Digest) TOTAL Metals (Acid Digest) Calculations/ Ratios Notes: Nutrient Block ID: Crop: Client: Units Oats Nitrogen N % 1.11 Phosphorus P % 0.19 Potassium K % 1.18 Sulphur S % 0.12 Carbon C % 44.5 Calcium Ca % 0.15 Magnesium Mg % 0.10 Sodium Na % 0.31 Copper Cu ppm 5 Zinc Zn ppm 13 Manganese Mn ppm 223 Iron Fe ppm 68 Boron B ppm <1 Molybdenum Mo ppm <0.2 Cobalt Co ppm 0.1 Silicon Si ppm 206 Nitrogen : Sulphur Ratio Nitrogen : Phosphorus Ratio Nitrogen : Potassium Ratio Carbon : Nitrogen Ratio see note 5 Crude Protein units 9.3 units 6.0 units 0.9 units 39.9 % All analysis is dry weight - Samples dried at 70 C for 24hours prior to fine grinding 2. Unless requested, leaf samples are NOT washed to remove salt spray or liquid fertilizers prior to analysis 3. Samples are microwave digested with nitric acid and read on the ICP-MS 4. Carbon/ Nitrogen/ Sulfur measured using a LECO CNS2000 Analyser 5. mg/kg = ppm 6. By Calculation:- Crude Protein = %N x Nitrate/Ammonium/Chloride measured on a water extract. 8. Moisture based on sample dried at 105 C Guideline Guideline OATS OATS (Avena sativa) Refer to note 7 below Adequate Deficient < < < < < <0.11 <0.5 >3.3 < <4-11 >30 < < <

31 EAL Plant Leaf Sampling Guide Paper bags are best for leaf sample collection We can analyse a single leaf but a couple hundred grams best the lab 40 C dries and grinds this volume If crop problems: collection of leaves from problem plants and comparison with leaves collected from good plants is an easy solution to locating deficiencies/ toxicities. Reference for sample collection and nutrient guide: Reuter D.J. & Robinson J.B Plant Analysis An Interpretation Manual. Inkata Press. Bryson, Mills, Sasseville, Joes and Barker, Plant Analysis Manual III, MicroMacro Publishing, ASPAC.

32 EAL Plant Leaf Sampling Guide

33 Compost Nutrients, other than carbon, are typically concentrated in the process (unless lost from water leaching, volatisation, etc). Partitioning of nutrients in compost varies between total available and soluble. Analysis of composts typically as Totals based on the concept that organic matter breaks down in soil. Wide range of analysis options including Aus Standards, available, soluble nutrients, etc.

34 Organic matter and Conductivity Conductivity ms/cm % Total Carbon % Total Nitrogen

35 'TOTALS' AVERAGES 2014 EAL average data collected during Soil Compost TOTAL Manures Chicken Manure Other Manures AVERAGES AVERAGES AVERAGES AVERAGES AVERAGES 200 samples 200 samples 66 samples 23 samples 36 samples Macronutrients Micronutrients Heavy Metals Nutrient Units Nitrogen N % Phosphorus P % Potassium K % Sulphur S % Carbon C % Calcium Ca % Magnesium Mg % Sodium Na % Copper Cu mg/kg Zinc Zn mg/kg Manganese Mn mg/kg Iron Fe mg/kg 35,600 16,230 6,840 2,312 9,555 Boron B mg/kg Molybdenum Mo mg/kg Cobalt Co mg/kg Silicon Si mg/kg 1,113 2,758 1,811 1,265 2,119 Aluminium Al mg/kg 23,848 7,230 3,789 1,176 5,601 Selenium Se mg/kg Cadmium Cd mg/kg Lead Pb mg/kg Arsenic As mg/kg Chromium Cr mg/kg Nickel NI mg/kg Mercury Hg mg/kg Silver Ag mg/kg <1 2 <1 <1 <1

36 Total other nutrient averages Northern NSW MS Li%7 Be%9 V+1%51 Sb%121 Sr%88 Ba%138 Tl%205 Bi%209 U%238 Th%232 Br%79 P%31 LITHIUM BERYLLIUM VANADIUM ANTIMONY STRONTIUM BARIUM THALLIUM BISMUTH URANIUM THORIUM BROMIDE PHOSPHORUS ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm ppm AVERAGE Standard%Deviation MINIMUM MAXIMUM SAMPLE%NUMBERS

37 Questions?