The document summarizes a meta-analysis of 178 articles on dryland restoration techniques globally. It found that the most common active restoration techniques were planting, seeding, nutrients addition, and irrigation. Statistics on 80 articles that reported data found that mycorrhizal inoculation, planting, vegetation management like mowing/grazing, and water addition generally had medium to large positive effects on restoration outcomes, while carbon amendment, seeding, and nutrients addition had smaller or negative effects. However, many studies lacked control comparisons and evaluations of costs, productivity, and plant-animal interactions were limited.

1. A synthesis of dryland restoration
techniques
Contact information
mflormiguel@gmail.com
Florencia Miguel (ResearchGate)
M Florencia Miguel, Christopher J Lortie, H Scott Butterfield
1
ensia.com

2. Main objetives
To conduct a meta-analysis of techniques for
vegetation restoration on drylands globally.
To determine the most effective techniques for
vegetation restoration on drylands.
Main
questions
1. What is the global extent of research that directly
examined restoration of drylands?
2. What were the common measures?
3. Is the restoration of vegetation a common and
primary focus?
4. How relatively effective were the techniques?
2

3. ➢ Search- Literature compilation
3
- Web of Science and Scopus
- restoration desert vegetation
- Published articles with available data
- No reviews, no book chapters
- Filter by journals and select english language
Bibliometric resources
Inclusion criteria
Terms

4. ➢ Sort
PRISMA report
4
Duplicates removed
Rational for exclusion:
review, not restoration, not
drylands, no data,
theoretical
N° of articles to
extract data= 178

5. Article locations and type of restoration
n= 178
5
➢ Synthesize and Summarise

6. Type of restoration
Frequency of articles with different disturbances and type of restoration
n= 178
6

7. 7
Intervention Techniques
Carbon amendment
carbon addition
top soil removal
Mycorrhizal inoculation mycorrhizal inoculation
Nutrients
fertile islands
biostimulants
fertilization and irrigation
nutrients addition
soil amendments
soil carbon and enzymes
soil nutrients
Planting
planting, clay and hidrogel
mechanical disturbance and planting
micropropagation of mosses
planting, composted addition,
mycorrhizal inoculation
planting, fungal inoculation
planting, glyphosate
planting, grazing exclusion
planting, irrigation, hydrogel
planting, mycorrhiza, hydrogel, wood
obstruction
planting
planting, soil amelioration
Intervention Techniques
Seeding
seeding, hollows-dyker plough,
furrows-ripper/sub-soiler and
walking-stick planter
seeding, chemical, burning
seeding, cutting, grazing
treatments
seeding, fencing
seeding, fire
seeding, gypsum (CaSO4) and
organic mulch
seeding, herbicide, nutrients
seeding, inoculation
seeding, irrigation
seeding, micro-topographic relief,
fire, grazing
seeding, mowing and herbicide,
mulching (straw and sawdust)
seeding, mulching, weeding
seeding, ripped, disked,
fertilization
seeding, seedbed preparation
seeding, soil tilling, fertilization
seeding, tackifier, harrowed
List of categories (intervention) and techniques
n= 178

8. 8
Intervention Techniques
Vegetation
ants as indicators
burning and mowing
chemical, mechanical control
genetics
germination and survival
grazing exclusion
herbicide, herbivore exclosures, and shelter tubes
mowing, grazing
natural recovery
rotational grazing
seed arrival and retention
seed bank
seedling herbivory
shelters
herbicide
Water addition
irrigation, planting, weed control
irrigation, planting, mulch
water addition
irrigation, seeding
irrigation
Soil
mycorrhizal fungi
natural recovery
soil microbial
Soil crusts
biological soil crusts
litter crust
Facilitation
facilitation
foundation species
shrub facilitation

9. Type of restoration
Different interventions (categories of techniques) and type of restoration
n= 178
9

10. Type of restoration
Different outcomes measured and type of restoration
10

11. 11
Intervention Techniques
Carbon amendment
carbon amendment
carbon addition, top soil removal
Mycorrhizal inoculation mycorrhizal inoculation
Nutrients
nutrients addition
fertilization, biostimulants, seeding
Planting
planting
planting, grazing exclusion
fertile islands
Seeding
seeding, soil amendment
seeding
seeding, planting
seeding, mulching, weeding
seeding, herbicides, activated carbon
seeding, fencing
seeding, irrigation
seeding, mowing and herbicide, mulching (straw and
sawdust)
seeding, ripped, disked, fertilization
seeding, grazing
seeding, seedbed preparation
Vegetation
herbicide
mowing, grazing
Water addition
seeding, irrigation
water addition
planting, irrigation, mulch
irrigation
irrigation, planting, weed control
Articles with data
extracted n= 80
Active type of
restoration
Statistics

12. ➢ Statistics
Active interventions mean effect sizes, relevance and p-values
n= 80
12
Active interventions Mean effect size Relevance p-value
Carbon amendment -0.7156 Medium 0.02
Mycorrhizal inoculation 0.7569 Large 0.68
Nutrients 0.1106 Small <0.0001
Planting 0.3645 Medium <0.0001
Seeding -0.3096 Small <0.0001
Vegetation 0.3581 Medium 0.01
Water addition 0.9771 Large 0.05
0-50% change: small
51-100% change: medium
101% change: large

13. 13
No effect Increase in the level
of an outcome
Decrease in the level
of an outcome
+
+
+
-
+
+
-
Outcomes

14. 14
Effect size p-value Intervention Technique
- M 0.02 Carbon amendment
carbon amendment
carbon addition, top soil removal, seeding
+ L 0.68 Mycorrhizal inoculation mycorrhizal inoculation
+ S <0.0001 Nutrients
nutrients addition
fertilization, biostimulants, seeding
+ M Planting
planting
<0.0001 planting, grazing exclusion
fertile islands
- S <0.0001 Seeding
seeding, soil amendment
seeding
seeding, planting
seeding, mulching, weeding
seeding, herbicides, activated carbon
seeding, fencing
seeding, irrigation
seeding, mowing and herbicide, mulching (straw
and sawdust)
seeding, ripped, disked, fertilization
seeding, grazing
seeding, seedbed preparation
+ M 0.01 Vegetation
herbicide
mowing, grazing
+ L 0.05 Water addition
seeding, irrigation
water addition
planting, irrigation, mulch
irrigation
irrigation, planting, weed control

15. 15
To consider
Control or benchmark situation to compare intervention effects (16/80, 20% of
evaluated articles did not include a control situation)
Cost evaluation of active techniques
Modified systems productivity and functions scarcely evaluated
Plant-animal positive interactions (e.g. seed dispersal, pollination) scarcely
evaluated