Chemistry Reference
In-Depth Information
2.2 Stewardship Index for Specialty Crops
The Stewardship Index for Specialty Crops (SISC) is a multi-stakeholder
initiative working to develop a system for measuring sustainable performance
throughout the specialty crop supply chain. The effort aims to establish a
common suite of outcomes-based metrics
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to enable operators at any point
along the supply chain to benchmark, compare and communicate their
performance in meeting sustainability goals. Currently, there are six metrics in
the
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pilot-testing
phase,
which
fall
under
four
categories:
Energy,
Soil,
Nutrients and Water.
The SISC Soil metric focuses on soil organic matter (SOM), the organic
fraction of the soil, excluding non-decomposed plant and animal residues. The
amount of total organic carbon (TOC) present in the soil - which is used as an
indicator of SOM - is divided by the soil's potential to store organic carbon,
which is determined by the US Department of Agriculture's (USDA) Soil
Management Assessment Framework (SMAF).
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Increasing amounts of SOM,
reflected as an increase in the value of the metric, signifies the soil's ability to
improve nutrient delivery to plants, retain water, drain excess water and resist
disease and erosion. To normalise against variability due to climate, soil type
and soil texture, SOM is compared with a site-specific estimate of the soil's
potential to hold SOM.
2.3 Cool Farm Tool
Developed by the University of Aberdeen, the Cool Farm Tool
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is a farm-
level greenhouse gas calculator that estimates net greenhouse gas emissions
from agriculture. Two of the calculator's six input sections, which include:
Crop Management, Sequestration, Livestock, Field Energy Use, Processing
and Transport, cover soil parameters.
Under the Crop Management section, producers are asked to report on the
soil texture, soil moisture, soil organic matter, drainage capacity and pH of the
field under analysis. Producers must also identify which fertilisers they use,
method and rate of fertiliser application, whether or not compost and/or
emissions inhibitors are used and how much crop residue is managed post-
harvest. The intent of the questions is to estimate emissions (primarily nitrous
oxide; N
2
O) from the soil and from crop residue.
In the Sequestration section, producers report on land use and farm
management changes, such as conversion of grassland to arable production,
forest clearing, changes in tillage methods, cover cropping, compost and
residue incorporation. Where applicable, producers may also enter informa-
tion on annual biomass accumulated or removed from productive tree species
in or near the field. The cumulative total of the Crop Management and
Sequestration sections indicates the amount of soil C accumulated or lost from
the production system and provides producers with an assessment of how
management and land use changes affect the operation's overall greenhouse
