Method of quantifying an indicative soil carbon measure

Abstract

The present invention is broadly directed to quantifying an indicative soil carbon measure broadly comprising: sampling aggregate from soil to obtain an aggregate sample; physically testing the aggregate sample involving: (a) one or more physical tests for assessing one or more physical properties of the aggregate sample selected from moisture content, strength, textural behaviour, and depth of organic matter penetration; (b) determining a physical measure of the aggregate sample from said one or more physical tests; and chemically testing the aggregate sample involving: (i) one or more chemical tests for assessing one or more chemical properties of the aggregate sample selected from pH, water coherence, organic matter penetration, and odour; (ii) determining a chemical measure of the aggregate sample from said one or more chemical tests; presenting an indicative soil carbon measure for the soil including both the physical measure and the chemical measure of the aggregate sample.

Description

METHOD OF QUANTIFYING AN INDICATIVE SOIL CARBON MEASURETechnical Field

[0001] The present invention is broadly directed to a method of quantifying an indicative soil carbon measure. In one aspect the method involves sampling aggregate from which physical and chemical tests are applied to obtain the indicative soil carbon measure. In another aspect the indicative soil carbon measure for any given landscape is derived from organic and systems measures based on biological or systems observations, and physical tests.Background of Invention

[0002] The prior art includes Visual Soil Assessment (VSA) guidelines published by G. Shepherd which involve soil observation tests from which the overall health of the topsoil is determined for the purposes of cropping. Each of the outputs from the soil tests are mathematically weighted (depending on the significance of that test) and the weighted outputs are then combined for an overall soil result. The overall soil result is compared with plant indicators and this information is used for soil management. Soil management practices are recommended depending on the overall soil result obtained from the VSA guidelines and associated plant comparisons.Summary of Invention

[0003] According to a first aspect of the present invention there is provided a method of quantifying an indicative soil carbon measure comprising: sampling aggregate from soil to obtain an aggregate sample; physically testing the aggregate sample involving:(a) one or more physical tests for assessing one or more physical properties of the aggregate sample selected from moisture content, strength, textural behaviour, and depth of organic matter penetration;(b) determining a physical measure of the aggregate sample from said one or more physical tests; and chemically testing the aggregate sample involving:(i) one or more chemical tests for assessing one or more chemical properties of the aggregate sample selected from pH, water coherence, organic matter penetration, and odour;(ii) determining a chemical measure of the aggregate sample from said one or more chemical tests; presenting an indicative soil carbon measure for the soil including both the physical measure and the chemical measure of the aggregate sample.

[0004] According to a second aspect of the invention there is provided a method of quantifying an indicative soil carbon measure, said method comprising: assessing organic characteristics of a landscape based on one or more (a) biological observations selected from the presence of mushrooms or soil fungi, and plant diversity, or (b) physical tests selected from a cotton degradation test, and penetrometer test; determining an organic measure of the landscape from said one or more biological observations or physical tests; assessing systems characteristics of the landscape based on one or more (i) physical tests including infiltration test, or (ii) systems observations selected from water retention and springs on slopes, eco-corridors, and wetlands; determining a systems measure of the landscape from said one or more physical tests or systems observations; presenting an indicative soil carbon measure including both the organic measure and the systems measure of the landscape.

[0005] Preferably the step of determining a measure involves assigning a number rating to said test or observation based on a predetermined rating standard relevant to the test or observation. More preferably each of the measures equals the sum of the number ratings assigned to each of the tests or observations for the measures without mathematical weighting of the tests or observations.

[0006] Preferably the step of presenting the indicative soil carbon measure involves independently presenting both (a) the physical measure and the chemical measure (of the first aspect), or (b) the organic measure and the systems measure (ofthe second aspect). More preferably said measures of the indicative soil carbon measure are presented alongside one another.

[0007] In this patent specification, reference to the indicative soil carbon measure includes what is to be understood as natural capital in an associated landscape.Detailed Description

[0008] In an embodiment of a first aspect of the technology there is a method of quantifying an indicative soil carbon measure from an aggregate sample, typically including topsoil and subsoil. The method of this aspect broadly comprises: sampling aggregate from soil to obtain an aggregate sample; physically testing the aggregate sample involving:(a) one or more physical tests for assessing one or more physical properties of the aggregate sample selected from moisture content, strength, textural behaviour, and depth of organic matter penetration;(b) determining a physical measure of the aggregate sample from said one or more physical tests; and chemically testing the aggregate sample involving:(i) one or more chemical tests for assessing one or more chemical properties of the aggregate sample selected from pH, water coherence, organic matter penetration, and odour;(ii) determining a chemical measure of the aggregate sample from said one or more chemical tests; presenting an indicative soil carbon measure for the soil including both the physical measure and the chemical measure of the aggregate sample.

[0009] It is expected that sampling of the aggregate will occur at at least one location in every paddock from which an indicative soil carbon measure is to be quantified. The aggregate sample can be taken from anywhere in the paddock provided subsequent samples are taken from approximately the same location. The general steps involved in obtaining an aggregate sample are as follows:1. dig a hole to a depth of approximately 30cm for extracting the aggregate sample to obtain the indicative soil carbon measure from the same hole;2. obtain discrete samples from the aggregate sample at a depth of around 30 to 100mm (topsoil);3. obtain discrete samples from the aggregate sample at a depth of around 300 to 350mm (subsoil);4. whilst digging the hole from which the aggregate sample is extracted, observe and record at what depth the soil changes from a black or dark brown to a much lighter colour.

[0010] It is to be understood that when conducting the physical or chemical tests of the first aspect where topsoil and subsoil may be required, the tests are performed on discrete samples obtained from the aggregate sample extracted from the same hole. It is recommended that a unique descriptor or name is given to each aggregate sample or hole so that subsequent testing can be performed in approximately the same location. In this example, where the method is deployed in an App from a smartphone or tablet with GPS capabilities, the location at which the aggregate sample is extracted can be accurately recorded using GPS data.

[0011] In this embodiment of the first aspect the aggregate tests for deriving the indicative soil carbon measure are to be performed every three months. The quarterly tests are separated into four (4) physical tests and four (4) chemical or physiochemical tests. Each of the physical or chemical tests are rated or scored from 1 to 5 based on predetermined rating standards reflecting the impact from improvement of increased soil carbon or landscape function. Thus the value 5 represents the property or characteristic if soil carbon was at its highest potential, and the value 1 represents the impact if no soil carbon was present. In this embodiment the quarterly test results are determined for respective of the physical and chemical measures by summing the ratings or scores for each of the four (4) physical tests and four (4) chemical tests. This means that the highest possible determined physical or chemical measure is 20. Importantly the physical and chemical measures are presented independent and in this case alongside one another akin to the vision test with a highest possible indicative soil carbon measure of 20 / 20. This maximum soil carbon measure is indicative of a soil with the optimum soil organic carbon content.

[0012] In this embodiment of the first aspect, physical testing of the aggregate sample is conducted as set out below. It is to be understood that any one or more combinations of the physical properties or associated tests may be selected in determining the physical measure of the aggregate sample.A. Moisture Content:

[0013] In this example the moisture content test assesses the dryness or wetness of an aggregate / clod. Dig 5-10cm with a shovel or auger and set aside some soil as your topsoil. The aggregate sample is obtained at a depth of around 30cm and used as the subsoil sample. With this subsoil aggregate in hand, the moisture level is based on how it feels according to the following rating standard. The scoring system rates either very wet or very dry as low or detrimental.1. Saturated.2. Very Dry.3. Allows deformation under pressure (i.e. slightly moist).4. Take a number of aggregates / clods in hand and squeeze them together to form a ball. With a hard squeeze, the ball (bolus) becomes more moist and after releasing the pressure, it does not return to its original shape, or it crumbles.5. With a moderate hand squeeze, free water appears on the ball (bolus) and when releasing pressure it reverts back to 80% of its former shape.B. Strength of Aggregate / Clod

[0014] In this example the strength test is applied to an aggregate / clod of the most common size from the aggregate sample extracted from the hole. This test involves hand squeezing the aggregates with a finger and thumb and observing what happens using the rating standard below.1. Many massive aggregates (clods >4cm2) and it is not possible to shatter aggregate (ped) between the finger and thumb.2. Many clods but smaller in size (mostly <4 cm2) and the ped shatters or breaks into dust and smaller peds (without deforming).3. In an attempt to deform the ped with your thumb, part of the ped breaks off but the entire ped does not deform or shatter.4. The ped squeezes but has plastic failure as the associated clay is wet / damp and it squeezes out between the fingers rather than cracking, i.e. it does not rebound to its previous shape.5. Ped deforms and has a degree of rebound.C. Textural Behaviour

[0015] In this example the test for textural behaviour is applied to a large aggregate (or several aggregates). The aggregates are placed in the hand and the following actions are attempted and the most relevant rating standard applied.1. The sample is rolled in the hand and exhibits very little to no organic matter and cannot be rolled without completely breaking apart. The rolled aggregate may be clayey and wet, and it can be rolled into a worm of 3-5 cm or more that does not break.2. The sample includes yellow and grey sand or silt that, when placed on the hand, separates into individual particles. The sample readily moves across the hand when blowing on it.3. The sample is loamy but breaks into small clumps when rolled between the hands (like willowing wheat between hands), and leaves clay and silt on the palms, with pieces of sand rolling away.4. The sample has dark aggregates that need vigorous rolling to separate into particles of stones, sand, silt or clay.5. The sample when squeezed by hand includes aggregates which are spongy, resist rolling, and don’t break apart readily.D. Depth of Organic Penetration (from the surface)

[0016] In this example the organic penetration test is performed when the hole from which the aggregate sample is extracted is first excavated and before filling the hole in. It may be necessary to clean the face of the hole to estimate the depth the organic matter penetrates before a colour change occurs. In applying the rating standard below, organic rich soil is understood to be coloured black to dark brown(chocolate brown). If the colour boundary is very gradual or variable it may be necessary to estimate what is considered to be the appropriate test for the boundary, provided the same boundary test or logic is applied each time.1. No or less than 2.5cm (1”) of organic rich topsoil.2. Organic rich topsoil layer is less than 5 cm (1-2”).3. Organic rich topsoil layer penetrates 15 cm (2-6”).4. Organic rich topsoil layer penetrates 1-30 cm (6-12”).5. Organic topsoil layer extends greater than 30 cm (>12”).

[0017] In this embodiment of the first aspect, the chemical or physiochemical testing of the aggregate sample is conducted as set out below. It is to be understood that any one or more of the chemical properties or associated tests may be selected in determining the chemical measure of the aggregate sample.E. Soil pH

[0018] In this example the Raupach indicator soil pH test kit from Inoculo Laboratories is used. The steps for performing the pH test are as follows: (i) place a small aggregate sample of around 1cm3 on a non-porous surface like an old ceramic tile, (ii) take a twig and spray 2-3 drops of Raupach indicator onto the associated ped, and mix with the twig until the small aggregate breaks up in the indicator (if too dry add some more indicator), (iii) apply the white powder (barium sulfate) to the now moistened small ped (the white powder is a colour fixer), (iv) match the colour of the powder on the small ped to the pH colour chart and record the matching pH number.

[0019] The following rating standard is then applied to the pH result to obtain the pH rating. This pH rating standard is used for both the topsoil and the subsoil sample.F. Modified Ped / Aggregate Emerson Test

[0020] In this example the water coherence of the aggregate sample is determined by applying a modified ped / aggregate Emerson Test. Two (2) discrete samples are obtained, one from the aggregate sample extracted from the hole and the other being a pinch of blackish sediment from a drain or dam pond bottom. The first sample being aggregate of 2cm3is placed in a container (e.g. small jar) filled with tap water and observed according to ratings 1 to 3 of the following rating standard. The second sample is dispersed into another small jar filled to the brim with tap water. The jar is sealed with a lid and then the aggregate / water mixture observed according to ratings 4 and 5 of the rating standard.1. Disperses fully within 10 minutes and water becomes cloudy brown with dispersed clay, or does not slake dissolve or alter after five (5) days.2. Slakes fully (ped slumps into particles but does not create clay cloud) within 10 minutes.3. Partial slakes due to air loss and some labile carbon dissolution after 2 hours.4. Partly slakes between 2 and 8 hours.5. Slumps or slakes only after glomalin dissolves after between 3 and 8 days by reducing bacteria.G. Organic matter penetration test

[0021] In this example the organic matter penetration test involves visual inspection of the aggregate sample or discrete samples from the hole. This may involve breaking clods, big aggregates and small aggregates and classifying the broken sample according to the following rating standard1. Light brown (or red, or yellow or grey) throughout with negligible colour change.2. Some darkening on outside and along macroporosity (roots and cracks).3. Dark brown or reddish brown covering most aggregates, penetrating only about 1 cm with lighter colours inside the aggregate.4. Dark brown or reddish brown covering most of the aggregates, penetrating over 50% of radius of the aggregate with lighter colours in the centre.5. All peds uniformly dark brown to chocolate brown (impact of red iron minerals covered by organic matter).H. Smell

[0022] In this example the odour or small test is conducted while digging, typically in the course of extracting the aggregate sample. The following rating standard is applied depending on smell detected during digging or thereafter when by hand breaking sods, clods, and peds and smelling.I. Sulfur or swampy smell.2. Sour or acid smell.3. Dry dirt smell such as that exhibited when fresh rain is associated with an actinomyces smell.4. Earthy smell.5. Strong sweet earthy smell.

[0023] Although the preceding physical and chemical tests are generally described as aggregate tests, it is to be understood that these tests are undertaken on both clods and aggregates as effectively it is a measure of moving from one form to other. In the field of regenerative agriculture the presence of clods is considered detrimental whereas the presence of aggregates is considered beneficial. It is to be understood that the general objective is to have the soil structure created by microbial activity and held together by organic “glues”, to consist entirely of aggregates. In better understanding the preceding physical and chemical tests, the units of soil structure, peds, clods, and aggregates are explained below.

[0024] Peds are a unit of adhered soil. Apedal means the soil has no structure at all and is not readily broken into separate units. This means it is just all sand, cemented or loose or all clay and exceptionally difficult to dig unless loose sand. A ped is a discrete unit of soil either lightly held together by mineral cements or organic glues. Peds typically consist of clods or aggregates but the way they are held together is different.

[0025] Clods are held together by surface adhesion and inorganic cements. Clods are larger than aggregate, 2cm3to 20 cm3and have a greater range. They often contain very little organic matter. They are anything but size optimised and represent the shearing of tillage or digging and the creation of mineral cements as water is evaporated from the pores. These cements often rapidly dissolve when water is returned to the pore which is why they are so strong when dry and so weak when wet. If the mineral cement is broken or dissolved away altogether clods rapidly turn to dust and can form dust storms, unlike aggregates which do not behave this way.

[0026] Aggregate includes micro aggregates held together by organic glues. Aggregates are size optimised by microbes for the balance between passage of air and water and maximum extraction of nutrients. Aggregates vary in size from typically 0.5cm3to 3cm3.

[0027] In an embodiment of a second aspect of the technology there is a method of quantifying an indicative soil carbon measure of a landscape, typically based on organic and systems characteristics. The method of this aspect broadly comprises: assessing organic characteristics of a landscape based on one or more (a) biological observations selected from the presence of mushrooms or soil fungi, and plant diversity, or (b) physical tests selected from a cotton a degradation test, and penetrometer test; determining an organic measure of the landscape from said one or more biological observations or physical tests; assessing systems characteristics of the landscape based on one or more (i) physical tests including infiltration test, or (ii) systems observations selected from water retention and springs on slopes, eco-corridors, and wetlands; determining a systems measure of the landscape from said one or more physical tests or systems observations; presenting an indicative soil carbon measure including both the organic measure and the systems measure of the landscape.

[0028] In this embodiment of the second aspect the observations or tests for deriving the indicative soil carbon measure are to be performed annually. The annual observations / tests are separated into four (4) biological observations or physical testsfor assessing organic characteristics of the landscape, and four (4) physical tests or systems observations to assessing systems characteristics of the landscape. Each of the organic or systems characteristics are rated or scored from 1 to 5 based on predetermined rating standards reflecting the impact from improvement of increased soil carbon or landscape function. In line with the first aspect the annual tests results are determined for respective of the organic and systems characteristics by summing the ratings or scores for each of the four (4) biological observations or physical tests, and four (4) physical tests or systems observations. This means that the highest possible determined organic or systems measure is 20.

[0029] In this embodiment of the second aspect of the technology the indicative soil carbon measure is a function of the movement of organic carbon with depth which reflects improvement in water management over the landscape or farm. It will be understood that changes in the indicative soil carbon measure reflect changes in organic carbon typically as a result of landscape improvement measures undertaken. It is expected that improved financial and natural capital returns will be achieved by optimising the indicative soil carbon measure derived from organic and systems characteristics according to this embodiment of the second aspect of the invention.

[0030] In this embodiment of the second aspect, the biological observations or physical tests for determining the organic measure for the landscape are set below. It is to be understood that any one or more of the tests or observations may be selected in determining the organic measure of the landscape.I. Field Mushrooms / Fairy Rings / Hyphae

[0031] In this example the biological observation pertaining to mushrooms or soil funghi involves visual inspection of the undisturbed landscape or paddock, and digging up random areas of the landscape for visual inspection. In both cases it is the presence of field mushrooms, fairy rings, and hyphae in plant roots which are of interest. The following rating standard is then applied to determine this organic characteristic.1. No field mushrooms in the last 12 months and no hyphae present in soil with very little organic matter.2. Isolated occurrence of field mushrooms. Hyphae only in soil associated with manure or urine grass patches. Field mushrooms are surrounded by small patches of green grass.3. Field mushrooms occur more commonly and fairy rings may occur. Hyphae apparent in over 30% of soil randomly inspected. Grass is greener where mushrooms occur.4. When field mushrooms and fairy rings occur, it is over most of the paddock. Grass is uniformly green and there is no obvious association of healthy grass where mushrooms grow. Over 30% of soil inspected has hyphae present in the top 30cm.5. Hyphae is present in all topsoil (<30cm) inspected and is found in 30% of soil samples of >30cm depthJ. Plant Diversity

[0032] In this example plant diversity is visually assessed for pasture in the landscape or paddock. The following rating standard is selected for either “Pasture” or “Cropping: and applied in determining the plant diversity rating.Pasture1. Less than 3 separate species.2. 4-6 separate species.3. 7-10 separate species.4. 10-15 separate species.5. More than 15 separate species.

[0033] In order to maintain a rating of 3 or higher, the pasture must include all of legumes, tap root species, and C4 plants. If the pasture does not satisfy this rating requirement then the rating is moderated down 1 point.Cropping

[0034] In this example the plant diversity observation and rating standard is changed for cropping. In this case the following ratings standard applies.1. Annual grasses (C3) only in rotation typically two or more of wheat / oats / rice / barley / canola / cotton on a 2 to 5 year rotation.2. C3 grasses and legume in a regular 4 year rotation. Typically the legume is a pulse but can be green manure or cut for hay.3. C3 grass and legumes in complex rotation with use of knockdown herbicides.4. C3 grasses and a legume in complex rotation without knockdown herbicides (crimping).5. C3 & C4 grasses and legumes in complex rotation without knockdown herbicides or salts of acid fertilisers. Use alternate fertilisers to manufactured fertilisers to replace phosphorus, nitrogen, and potassium, or no fertiliser, instead managing the soil biome to release or fix fertilisers as needed.K. Cotton Degradation test

[0035] In this example the cotton degradation test is a physical test for determining organic characteristics and an organic measure of the landscape or paddock. This test involves burying a 100% cotton pair of underpants, a t-shirt, or a handkerchief at a depth between 50 and 75 mm ensuring at least 25 mm of soil covers the cotton garment which is left undisturbed for 90 days. After 90 days, the garment is uncovered and inspected and the following rating standard applied.1. Dirty and slightly mouldy, the fabric is still quite strong.2. Mouldy with some patches clearly having a worn look, readily rips.3. Many holes in the fabric, most fabric has an appearance of decay.4. Less than 30% of the fabric remains.5. Only the elastic waist band or non cotton components remain.L. Penetrometer Test

[0036] In this example the penetrometer test assists in determining organic characteristics of the landscape. Either a penetrometer, or a steel rod (such as a piece of rebar about 1.2 metres long) with a protective rest pad at one end (to push downward by hand) can be used in this physical test. The penetrometer or steel rod is inserted into the ground as deep as possible only using applied hand pressure.The depth of insertion is then recorded and rated according to the following rating standard.1. 15 cm or less.2. 15-30 cm.3. 30-50cm.4. 50 - 100cm.5. More than 100cm.

[0037] In this embodiment of the second aspect, the physical tests or systems observations for determining the systems measure for the landscape are set out below. It is to be understood that any one of or more of the tests or observations may be selected in determining the systems measure of the landscape.M. Infiltration Test

[0038] In this example the infiltration test involves the following exemplary procedure. Using a bucket (20 litre pail) with the bottom removed record its diameter and strap a ruler or tape measure to the inside of the bucket. Push the bucket into the ground, bottom first ensuring not to push more than 50 mm deep. Check the bucket is evenly pushed in and the top of the bucket is level. If on bare or ploughed ground, place a cut ring of shade cloth or nylon seed bag onto the ground inside the ring of the bucket to prevent creating a hole when water is poured onto the soil surface inside the bucket. Pour 4 litres of water rapidly into the top of the bucket. If pouring the water may create a hole, place a coarse-woven cloth on the surface before pouring. Record the initial level and then record the level every 15 seconds for 2 minutes, then every 30 seconds for the next 3 minutes, then every minute for the next five minutes, then every 2 minutes for the next 10 minutes, then every five minutes for the next 10 minutes. If possible, thereafter take more readings at 40, 50 and 60 minutes and if using the App with a mobile phone or other deice record directly into the App. The infiltration test is then rated according to the following ratings standard.1. <5 mm / hr or more than 50mm / hr.2. 5 to 10 mm / hr.3. 25 - 35 mm / hr (low organic matter and typically poor aggregation).4. 10-15 mm / hr.5. 15-25 mm / hr or if 25-50 mm when organic matter is high (typically good aggregation).

[0039] It will be understood that these “flowrates” can be manually calculated based on the changes in level recordings, and the corresponding time intervals. If using the App it is configured to automatically calculate the “flowrates”.N. Non-stratigraphic Springs on slopes and water held on Slopes

[0040] In this example the water retaining and springs on slopes observations are determined based on the following rating standard.1. Spring appears in change of slope (unassociated with change in geological strata) after a rainy period where the area impacted by springs grows with time.2. Spring appears in change of slope after a rainy period and the area does not increase with time.3. Infiltration can be seen to be encouraged by tree corridors on crown and mid slope.4. Tree corridors, terraces and / or berms holding water along contour at midslope. Trees planted in corridors on slope inflection to stop salt water springs, known as the Keyline System.5. Tree corridors, terraces and / or berms distributing water from creek have moderate flow along contours across slopes. Trees are planted in corridors on slope inflection to stop salt water springs.O. Eco-Corridors and Tree Cover

[0041] In this example eco-corridor and tree cover observations are assessed for determining the corresponding systems measure based on the following definitions and guidelines.

[0042] An eco-corridor is a minimum 30 m wide and preferably 50 m wide and at least a two layered understorey Eco-corridors are planned to connect with neighbours existing and planned eco-corridors, regional bush reserves or long paddocks. They can also be used to be along slope inflection points where springs occur (Keyline) oraround the edge of salt water lakes or salt scalds. Eco-corridors can incorporate riparian zones and be part of alluvium recharge systems. It is understood that up to 20% and maybe higher of the area of the landscape or farm can be put to eco- corridors. The following rating standard is applied in determining ratings for eco- corridors1. No eco-corridors and no detailed plans for eco-corridors.2. Eco-corridors planned for the farm that integrate into the district but planting has not began or just begun.3. Eco-corridors planned for the farm that integrate into the district. Planting is well underway but has constraints against the ideal - less than 40 m wide, limited understory, inadequate fencing.4. Mostly or completely planted, 20% of farm area to eco-corridors, 40 - 50 m wide and multistoreyed but not yet regional connectivity.5. All of the above but regional connectivity and maintenance program including patterned cultural burning program.P. Wetlands and Flooding or Alluvium

[0043] In this example observations associated with wetlands, flooding, or alluvium are undertaken to determine this systems characteristic. It should be understood that slowing water flow in gully lines, ephemeral creeks and permanent waterways is necessary to prevent erosion. Properties with streams, creeks or rivers that contain alluvial deposits will often have substantial fertile flats as a result.Ensuring water is slowed as it moves down-slope or collects and flows in gullies and that alluvial flats are frequently recharged, sustains both a base flow for the river, and an all year water source for deep-rooted plants and trees. Slow moving water does not create gullies or incises into the landscape, and thereby protects against loss of land. Wetlands weirs and rock bars are nature's way of recharging alluvium and purifying water from both sediment and nutrients. These structures associated with controlling waterflow require planning for the farm or other landscape possibly with connectivity of river catchment into the district. The following rating standard is applied in determining ratings for wetlands, flooding, or alluvium.1. Heavily incised gullies and creeks and no wetlands, weirs or water slowing devices installed or planned.2. Surveyed and plan for water slowing devices.3. Commencement and enacting of plan.4. Installation of plan has begun.5. All wetlands weirs and water slowing devices in stream and on slopes and banks are planned and operations are at least 5 years into the plan.

[0044] In the embodiments of both aspects of the technology the indicative soil carbon measure is presented in a format showing both the physical and chemical measures of the aggregate of the first aspect, and the organic and systems measures of the landscape of the second aspect. In the first aspect the physical / chemical measures and the associated indicative soil carbon measure may be obtained for both aggregate samples from the topsoil (typically 0 to 30cm) and the subsoil (typically greater than 30cm). These separate topsoil and subsoil indicative carbon measures are combined with the organic and systems measures of the landscape of the second aspect. This means that for each paddock the described embodiment presents three (3) indicative soil carbon measures, namely (i) the topsoil physical / chemical aggregate measure rating out of 20 / 20, (ii) the subsoil physical / chemical aggregate measure rating out of 20 / 20, and (iii) the landscape organic / systems measure rating out of 20 / 20.

[0045] In the context of the first aspect of the invention the following table reflects an exemplary combined “Score” as well as an “Organic Carbon Improvement Score” indicating the opportunity to improve soil quality.

[0046] It is to be understood that the method of both aspects is not intended to provide a single overarching score as each suite of tests or observations represents an optimisation of different characteristics or parameters. For example, organic matter could be optimised in the upper 10cm but not deeper which will be apparent in the quarterly tests of the first aspect where individual layers of organic matter could be optimised. On the other hand, the method of the second aspect relying on organic or systems characteristics including observations pertaining to eco-corridors and water management are unlikely to provide insights into optimisation of organic matter at varied depths. It will be understood that the embodiments of both aspects in presenting indicative soil carbon against an ideal rating (such as 20 / 20) allows an operator or farmer to understand what facet of soil and landscape management needs further work. The method of both aspects thus provides relative measures of indicative soil carbon and is not intended as a soil health tool with absolute measures.

[0047] Now that embodiments of both aspects of quantifying an indicative soil carbon measure have been described, it will be apparent to those skilled in the art that the invention at least in its preferred form has the following advantages:1. it allows the operator or farmer to observe and understand improvements in soil by adopting the aggregate and / or landscape tests / observations in deriving an indicative soil carbon measure;2. the method provides a mechanism for tracking improvement in water holding capacity and landscape repair over a farm, typically annually;3. the method may be enabled via an online tool involving recordal, analysis and tracking of physical tests and observations to determine an indicative soil carbon measure;4. the method is not designed for use by soil scientist but rather extends to practically any user or observe having the requisite tools.

[0048] Those skilled in the art will appreciate that the invention as described herein is susceptible to variations and modifications other than those specifically described.

[0049] All such variations and modifications are to be considered within the scope of the present invention the nature of which is to be determined from the foregoing description.

Claims

Claims1. A method of quantifying an indicative soil carbon measure comprising: sampling aggregate from soil to obtain an aggregate sample; physically testing the aggregate sample involving:(a) one or more physical tests for assessing one or more physical properties of the aggregate sample selected from moisture content, strength, textural behaviour, and depth of organic matter penetration;(b) determining a physical measure of the aggregate sample from said one or more physical tests; and chemically testing the aggregate sample involving:(i) one or more chemical tests for assessing one or more chemical properties of the aggregate sample selected from pH, water coherence, organic matter penetration, and odour;(ii) determining a chemical measure of the aggregate sample from said one or more chemical tests; presenting an indicative soil carbon measure for the soil including both the physical measure and the chemical measure of the aggregate sample.

2. A method as claimed in claim 1 wherein the step of determining a measure involves assigning a number rating to said test based on a predetermined rating standard relevant to the test.

3. A method as claimed in claim 2 wherein each of the measures equals the sum of the number ratings assigned to each of the tests for the measures without mathematical weighting of the tests.

4. A method as claimed in any one of the preceding claims wherein the step of presenting the indicative soil carbon measure involves independently presenting both the physical measure and the chemical measure.

5. A method as claimed in claim 4 wherein said measures of the indicative soil carbon measure are presented alongside one another.

6. A method of quantifying an indicative soil carbon measure, said method comprising: assessing organic characteristics of a landscape based on one or more (a) biological observations selected from the presence of mushrooms or soil fungi, and plant diversity, or (b) physical tests selected from a cotton degradation test, and penetrometer test; determining an organic measure of the landscape from said one or more biological observations or physical tests; assessing systems characteristics of the landscape based on one or more (i) physical tests including infiltration test, or (ii) systems observations selected from water retention and springs on slopes, eco-corridors, and wetlands; determining a systems measure of the landscape from said one or more physical tests or systems observations; presenting an indicative soil carbon measure including both the organic measure and the systems measure of the landscape.

7. A method as claimed in claim 6 wherein the step of determining a measure involves assigning a number rating to said test or observation based on a predetermined rating standard relevant to the test or observation.

8. A method as claimed in claim 7 wherein each of the measures equals the sum of the number ratings assigned to each of the tests or observations for the measures without mathematical weighting of the tests or observations.

9. A method as claimed in any one of claims 6 to 8 wherein the step of presenting the indicative soil carbon measure involves independently presenting both the organic measure and the systems measure.

10. A method as claimed in claim 9 wherein said measures of the indicative soil carbon measure are presented alongside one another.

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