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COMMON METHODOLOGY, TERMS, AND UNITS OF MEASUREMENT FOR THE CASCADE PROJECT
KEY DEFINITIONS AND DETAILS OF METHODOLOGY
Site status
Intact; Reference; Non-degraded
Partly-degraded
Strongly-degraded
Site area
Study region
Landscape scale
Study site
Site
Field (30-50m2 ?)
Plot
Sub-plot (3m2 ?)
Micro-plot (3 x 3 m2 ) (for rainfall exclusion experiments)
Patch
Sampling point
Linear transect (50m)
Landscape Function Analysis (CSIRO, 2005)
The basis of measurements in CASCADE is the LFA manual: Landscape Function Analysis: procedures
for monitoring and assessing landscapes. pdf 2005
http://live.greeningaustralia.org.au/nativevegetation/pages/pdf/Authors%20T/7a_Tongway
Soil type, description, surface assessment (USDA?, CSIRO?)
The first step is to determine where to sample, in particular in which soil horizons. Therefore, a soil
description is needed first. Dig a hole to at least 30 cm depth. A deeper hole is better, or a corer
might be used to reach greater depth. Wet the soil to see colour differences. Describe the horizons
and take a sample from the upper one, and from the one below.
150-200 g of soil is needed each time. Alternatively, it is also OK to take 4 100 CC ring samples.
These can also be used to determine soil density. After taking the samples they can be removed
from the rings and put in a bag. Stones can be removed, as long as their volume is measured.
To determine stone fraction on the soil surface count the number of stones on a certain area, and
determine the size class of the stones. Violette Geissen will provide chart that helps estimate the
cover percentage
Distinguish the main root zone. Take a picture of the profile and of the soil surface. Do this for each
plot, so 9 times per study site. There are systems with multiple rings above one another; this
disturbs the soil less.
Measure pH in the field; this saves money.
Soil sampling
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1) Once at the beginning of the experiment: texture, soil density, pH, % organic matter, %C org, free
carbonate,
Ksat, infiltration rate, stone content, soil horizon depths, depth of groundwater (if relevant)
2) Sampling 2-4 times per year: %N tot (total), %N org (organic), %N min (mineralized), %P avail
(available), soil water content, electrical conductivity, microbial activity
3) Continuously in the partly-degraded land parcels: with a TDR (time domain reflectrometry)
system the soil water content will be continuously measured in the partly-degraded variants below
plants/tussocks and surrounding bare soil to study plant available water over time.
Soil samples for microbiology
Take samples evenly over depth. Use gloves to pick out the stones, this in order to avoid
contamination of the samples. Cool the samples (put in refrigerator). Jaap Bloem will look up the
transport options, as the samples need to be shipped to Wageningen. If there are patches, separate
samples are needed for the patches and for the area in between.
Plant sampling
1) Plant growth: leaf elongation, new shoots, height of main stem, basal diameter of main
stem, butt diameter (depending on plant species)
2) Plant reproductive effort: number of inflorescences, number of flowers/fruits per
inflorescence/plant (depending on plant species)
3) Plant physiology (water stress indicators): SLW (specific leaf weight), other "soft" traits, C13 Plant cover and height - Root biomass
Plant measurements
1. Growth
Height
a) select main stem, mark it permanently
b) measure height, use same stem each time
Diameter of shrub
a) Measure longest diameter
b) Measure diameter perpendicular to longest
Basal diameter (diameter closest to soil – 1 cm above soil)
a) randomly select 6 stems
b) mark these permanently. Susana will indicate how (action 20)
c) measure diameter with (digital) caliper, in 2 directions
d) count stems if there are more than 6
2. Reproductive effort
a) Visit site before fruiting (as fruits might be eaten)
b) Use thule fabric (as in wedding dress) to cover one branch
c) Fix fabric to prevent that fruits are lost (through falling or by being eaten)
d) After fruiting season count the fruits and weigh them
3. Ecophysical characteristic
a) Select 1 branch on south-facing side of shrub (as this side is most stressed)
b) Cut this branch and take it to the lab
c) Scan the leaves while fresh, make sure they do not fold. Include something of
known area (reference), and scan in black and white
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d) Put leaves in oven for 2-3 days; temperature around 60⁰C, but certainly below 70⁰C.
e) Weigh the leaves, this allows to calculate specific leaf weight. Use about 10 leaves
During the last sampling take a larger branch. Use the same procedure as above. After that continue
with this:
f) Grind the leaves for 13⁰C analysis in laboratory
g) Dry again after grinding
h) Send to laboratory
4. Germination
a) Look for established seedlings as most of the small ones die anyway
b) Look around the whole patch, up to a distance of 1 times the radius of the patch
c) For each seedling measure the distance to the centre point of the patch, as well as
the orientation
Do the same for resprouting
For grass, measurements are slightly different:
Growth: Measure height and cover. For cover the use of a grid might help. For height, what should
be measured is the height of the vegetative plant, not the height of the flower/fruit (there are
implements to help with determining this). At the end of the growing season determine the
biomass. To do this, the plants need to be harvested. This should be done separately for spikes and
for the rest of the plant. For grass small plots are sufficient; it is recommended to use 6 instead of 3.
Soil parameters only need to be determined in 3 of these.
Biomass (g m-2)
Species richness (100m2)
Water
Groundwater level
Water quality
Salinization
Ecosystem services
1) Provisioning services (forage, timber, fibre, game, etc.)
2) Regulating and supporting services (water and soil conservation, nutrient cycling, carbon
sequestration, etc.)
3) biodiversity
Using WOCAT methodology in WB7
Based on the premise that Sustainable Land Management (SLM) experiences are not sufficiently or
comprehensively documented, evaluated and shared, the global WOCAT initiative has developed
standardized tools and methods to compile and evaluate the biophysical and socio-economic
knowledge available on SLM at the local, regional and global scale. The tools allow SLM specialists
(including land users, agricultural advisors, project managers, government officers, etc.) to share
their knowledge of SLM implementation in-country and around the world.
The basic concept behind the WOCAT methodology at the local level entails
(1) assessing local case studies of successful SLM and their local spread and adoption,
(2) providing a standardized framework that allows comparison and sharing beyond the local scale,
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(3) inclusion of socio-economic as well as biophysical aspects,
(4) use of the knowledge of both specialists and land users as data sources, backed up
(triangulated) by scientific data where possible and
(5) simultaneously using the same tools for both (self-) evaluation and for knowledge sharing.
The key tools at the local level are two questionnaires on SLM technologies and SLM approaches,
and their respective databases. These two applied together constitute a case study, which can be as
small as one farmer’s field or may represent hundreds of square kilometres (catchments, districts,
etc). SLM technologies are the physical practices in the field, which are agronomic (e.g.
intercropping, contour cultivation, mulching), vegetative (e.g. tree planting, hedge barriers, grass
strips), structural (e.g. graded banks or bunds, level bench terrace, dams) or management measures
(e.g. land use change, area closure, rotational grazing) that control land degradation and enhance
productivity in the field. These measures are often combined to reinforce each other. The
questionnaire addresses the specifications of the technology (purpose, classification, design and
costs) and the natural and human environment where it is used. It also includes an analysis of the
benefits, advantages and disadvantages, economic impacts and acceptance and adoption of the
technology. Impacts are approximated through simple scoring by experts, but supplemented with
data where available.
The associated SLM approaches are the ways and means of support that help to introduce,
implement, adapt and promote those technologies on the ground. An SLM approach involves all
participants (policy makers, administrators, experts, technicians, land users, etc; actors at all levels),
inputs and means (financial, material, legislative, etc) and know-how (technical, scientific, practical).
Questions focus on objectives, operations, participation by land users, financing and direct and
indirect subsidies. Analysis involves monitoring and evaluation methods as well as an impact
analysis. Successful approaches are the key to the upscaling of technologies over larger areas and
more land users.
(Source: Schwilch G., Bestelmeyer B., Bunning S., Critchley W., Herrick J., Kellner K., Liniger H.P.,
Nachtergaele F., Ritsema C.J., Schuster B., Tabo R., van Lynden G., Winslow M. 2011. Experiences in
Monitoring and Assessment of Sustainable Land Management. Land Degradation & Development 22
(2), 214-225. Doi 10.1002/ldr.1040)
For general information about WOCAT: www.wocat.net
Questionnaires and databases on SLM technologies and approaches (case study level):
 https://www.wocat.net/en/methods/slm-technologies-approaches.html
https://www.wocat.net/en/methods/case-study-assessment-qtqa/database-manual.html
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