Stages of restoration of bare land, steppes and degraded soils

Stages of restoration of bare land, steppes and degraded soils

Restoration doesn't begin with planting trees. The correct sequence is usually:

stop deterioration → retain water → seal soil → bring back roots and microorganisms → restore grass cover → add shrubs and trees where they are ecologically appropriate → create a sustainable economy.

Especially important:a healthy steppe is not an underdeveloped forestSteppe and meadow ecosystems themselves possess high natural value. They cannot be automatically reforested. Trees are introduced in a mosaic fashion—in ravines, along waterways, at forest edges, near economic zones, and as shelterbelts.

General recovery sequence

Stage 0. Diagnostics: determine the cause of degradation

Before any work you need to understand,what exactly was destroyed.

Possible reasons

water erosion;

wind erosion;

overgrazing;

constant plowing;

compaction by heavy equipment;

lack of vegetation;

salinization;

contamination with heavy metals or petroleum products;

quarrying work;

felling;

fire;

violation of water regime;

lowering of groundwater levels;

invasive species;

loss of seed bank;

excessive use of fertilizers and pesticides.

What to explore

Minimum set:

structure and mechanical composition of the soil;

depth of the fertile layer;

density and presence of a plow sole;

pH;

organic matter;

electrical conductivity and salinity;

nitrogen, phosphorus, potassium;

calcium, magnesium and trace elements;

water absorption rate;

relief and flow directions;

existing vegetation;

seed bank;

possible contamination.

In contaminated or highly saline soils, simply planting may not solve the problem. Specialized remediation, drainage, leaching, contamination isolation, or phytoremediation are first required.

Step 1: Stop further destruction immediately

It is impossible to restore the land as long as the same load that destroyed it continues.

Necessary measures

temporarily exclude grazing;

close the movement of equipment through damaged areas;

stop plowing the slopes;

limit the collection of all plant biomass;

close uncontrolled roads and tracks;

stop the discharge of contaminated water;

protect areas from fires;

remove or control invasive plants;

change the direction of water movement.

Sometimes simply relieving pressure triggers natural regeneration faster and more cost-effectively than mass planting. In dry regions, fencing a degraded area from constant grazing and trampling often allows preserved roots and seed banks to regrow.sti-portal.fao.org)

For pastures

A complete grazing ban isn't always necessary forever. It's better to move on to:

rotational grazing;

short period of stay of animals;

long recovery period;

exclusion of grazing after drought and fire;

separate watering points;

control of the total population.

Animals can be part of the restoration, but only when their numbers and residence time are consistent with the productivity of the site.

Step 2: Stop Erosion

Bare soil can lose what took decades to build in just one heavy rain.

Wind erosion

To reduce it, use:

strips of dry grass and branches;

temporary straw mats;

hedges;

shrub strips;

low permeable wind barriers;

planting across the prevailing wind;

fixing sand with herbs;

stubble preservation;

mulch.

A windbreak doesn't have to be a completely solid wall. A partially permeable barrier reduces wind speed more gently and mitigates strong turbulence.

Water erosion

Used:

contour stripes;

stone lines;

wicker barriers made of branches;

small dams in gullies;

grassy spillways;

terraces on suitable slopes;

restoration of ravines;

living fascines;

root strengthening plants.

All structures must be able to safely drain excess water. An improperly constructed embankment can break through and further damage the structure.

FAO considers protection from wind and water erosion, sand stabilization and restoration of vegetation cover as central tasks of dryland rehabilitation. (Open Knowledge FAO)

Step 3: Retain Water in the Landscape

In arid zones, the main limitation is often not the total amount of precipitation, but rather the fact that water:

drains quickly;

evaporates;

carries away soil;

concentrated in ravines;

does not have time to penetrate to the roots.

Principle

Slow down - distribute - absorb - store - safely remove excess.

Possible elements

On almost level ground

shallow absorption ditches;

micro-drops;

holes around plants;

mulched strips;

small water collection bowls.

On gentle slopes

contour shafts;

crescentic catchments;

stone lines;

grass strips;

landing pockets.

In the ravines

a chain of small permeable dams;

stone-branch thresholds;

planting willows and other local moisture-loving species;

expansion of the flow into safe floodplain zones.

In large projects

ponds;

seasonal reservoirs;

floodplain restoration;

water collection from roads and roofs;

subsoil water accumulation;

infiltration basins.

Water harvesting in dry regions can simultaneously improve crop yields, soil health, water availability and local biodiversity.WOCAT)

Important limitation

Contour ditches cannot be built without calculation:

on landslide slopes;

on heavy, waterlogged clays;

above buildings;

near unstable slopes;

where water may cause subsidence.

Step 4: Cover the soil surface

Open soil overheats, loses water, and is destroyed by rain and wind.

Basic principles of healthy soil:

maximum continuous coverage;

minimal mechanical disturbance;

plant diversity;

living roots as much of the year as possible. (Natural Resources Conservation Service)

How to cover the ground

straw;

mown grass;

wood chips;

chopped branches;

leaves;

compost;

stubble;

ground cover plants;

stone mulch in dry areas.

What kind of mulch is suitable?

For agricultural strips

straw;

mown cover crops;

compost;

crushed plant residues.

For trees and shrubs

wood chips;

leaves;

branch mulch;

mature compost on top of the soil.

For very dry, rocky areas

gravel;

stone chips;

small stones that create shade and condensation microzones.

Mulch should not be placed close to tree trunks. Furthermore, in fire-prone areas, thick layers of dry organic matter should be separated by safety strips.

Step 5: Remove compaction and restore structure

Compacted soil may appear wet after rain, but the water stays on top and does not penetrate deeper.

Signs of compaction

puddles after light rain;

the roots grow horizontally;

very hard layer at one depth;

poor aeration;

weak activity of worms;

water flows down without being absorbed;

Plants are easily pulled out with short roots.

Methods

stopping movement on wet soil;

permanent technological tracks;

deep-rooted plants;

oil radish;

alfalfa;

clover;

chicory;

perennial cereals;

local mechanical loosening;

subsoiler without soil turnover;

introduction of organic material to the surface.

Mechanical tillage is only effective if vegetation immediately appears afterward. If loose soil is left bare, it will compact again and become susceptible to erosion.

Step 6: Restore pioneer plants

At the first stage, what is needed is not valuable fruit trees, but plants that can survive and change the environment.

Functions of pioneer species

quickly close the soil;

give roots;

accumulate organic matter;

reduce surface temperature;

trap dust and seeds;

improve water penetration;

create shelter for the following plants.

Main groups

Cereals

local fescue;

rump;

wheatgrass;

feather grass - for natural steppe;

local wheatgrass species;

millet;

sorghum in economic systems.

Legumes

clover;

alfalfa;

sainfoin;

clover;

shouts;

local milkvetches;

lotus.

Mixed herbs

yarrow;

chicory;

plantain;

sage;

native wormwood species;

local Asteraceae;

deep-rooted drought-resistant herbs.

Sowing

On heavily degraded soil it is better to use a mixture:

fast-growing annuals;

perennial cereals;

legumes;

local herbs.

Monoculture closes the soil but creates a less sustainable system.

Step 7: Restore Soil Biology

Soil is more than just sand, clay, and fertilizer. Its functions include:

bacteria;

mushrooms;

protozoa;

nematodes;

earthworms;

arthropods;

living roots;

decomposing organic matter.

What helps soil life

permanent roots;

plant diversity;

leaf litter;

wood residues;

compost;

lack of frequent plowing;

refusal of unnecessary fungicides;

reduction of mineral nitrogen;

reasonable grazing;

water and shadow.

Compost and microbial preparations

High-quality compost is useful as a source of:

organics;

microorganisms;

stable nutrients;

improved moisture capacity.

But "mycorrhiza from a bag" is no substitute for the right conditions. If the soil remains bare, overheated, saline, or is regularly treated with fungicides, the introduced fungi will not create a stable system.

Manure

Fresh manure should not be applied in a thick layer directly under young plants. It can:

burn the roots;

cause excess nitrogen;

increase salinity;

pollute water;

stimulate weeds.

It is better to use composted manure or distribute organic matter in small doses in combination with plant cover.

Step 8: Restore Fertility

Fertility cannot be reduced to NPK alone.

Required:

organic matter;

porous structure;

aeration;

moisture capacity;

balanced acidity;

available mineral elements;

biological activity;

surface protection.

Organic sources

compost;

plant residues;

cover crops;

manure after processing;

wood chips;

biochar mixed with nutritious compost;

green fertilizers.

Mineral correction

Applies only after analysis:

lime - for excess acidity;

gypsum - in some sodium soils;

phosphorus materials - in case of confirmed deficiency;

microelements - according to diagnostics;

clay - on extremely sandy technogenic substrates;

Sand should not be added to heavy clay without calculation.

It's best to saturate biochar with compost, manure infusion, or nutrient solution before applying it. Unsaturated material can temporarily bind some of the available nutrients.

Step 9. Introduce shrubs

Once the grass cover has already held the soil and stable water accumulation zones have appeared, shrubs can be introduced.

For steppe and dry zones

First of all, local species are needed:

rose hip;

hawthorn;

turn;

Caragana in its natural region;

juniper;

tamarisk in suitable saline areas;

they have become sea buckthorn;

dogwoods;

local wormwoods and shrubs.

Functions of shrubs

snow retention;

wind protection;

shadow creation;

bird feed;

nesting sites;

protection of young trees from animals;

accumulation of leaf litter;

connection of separate habitats.

It is better to plant shrubs in islands and strips, rather than in a uniform grid.

Step 10. Introduce trees only after preparing the environment

On bare ground, a single seedling faces several threats at once:

overheat;

wind;

evaporation;

herbivores;

lack of organic matter;

compaction;

sharp temperature fluctuations.

Therefore, it is better to plant trees after creation:

catchment microzone;

grass cover;

mulch;

shrub protection;

animal fencing.

Sequence of tree species

The first wave is stable preparatory types

Depending on the region:

willow in damp places;

alder;

birch;

pine;

rowan;

local acacia or bean trees;

tamarisk in moderate salinity;

local drought-resistant trees.

The second wave is durable frame types

oak;

linden;

elm;

maple;

fir and pine according to climate;

cedar pine;

chestnut;

walnut;

local fruit trees.

The third wave is shade-tolerant and rare species.

thousand;

fir;

forest fruit;

rare relict trees;

shade-tolerant shrubs.

In dry soils, trees improve infiltration, bind the soil with their roots, reduce wind, create shade, and moderate the microclimate. However, their density must be proportional to the water supply.Open Knowledge FAO)

Separately: How to restore the steppe

The steppe does not need to be turned into a continuous forest

The natural steppe consists primarily of:

perennial cereals;

mixed herbs;

bulbous;

soil crusts;

local shrubs;

rare trees in depressions and along the water.

Continuous afforestation can:

displace steppe plants;

deprive land birds of habitat;

increase water consumption;

change the fire mode;

disturb the historical landscape.

The correct model of steppe restoration

60–80% of the territory

local herbs;

legumes;

mixed grass;

managed grazing;

seasonal mowing;

preservation of open space.

10–20%

shrub islands;

but;

hedges;

corridors for animals.

5–15%

trees along the water;

protective forest belts;

shadow groups;

fruit and vegetable plantings near settlements.

This is only a guideline. In a true steppe conservation reserve, the proportion of trees may be significantly lower.

Separately: restoration of completely bare land

In a quarry, construction site or heavily eroded surface, even a full-fledged soil horizon may be absent.

Stages

1. Relief stabilization

remove dangerous waste piles;

soften slopes that are too steep;

create a safe spillway;

fill in the gullies;

create a microrelief.

2. Formation of the root layer

If necessary:

restore the preserved fertile soil layer;

mix mineral substrate with compost;

add clay fraction to sandy material;

eliminate toxicity;

Reduce rockiness only where it interferes with plants.

3. Fast coverage

hydroseeding;

straw mats;

branch mulch;

covering mixtures;

sowing in furrows and micro-wells.

4. Shrubs and pioneer trees

They are added only after the substrate has stopped actively eroding.

On man-made lands, it may be necessary to reconstruct the functional system “soil-plants”, rather than simply greening the surface.FAOHome)

Separately: saline soils

Signs:

white crust;

poor germination;

leaf burn;

poor absorption;

destruction of structure;

brackish groundwater.

What to do

Determine the type of salts and sodium level.

Eliminate the source of salinity.

Provide drainage if possible.

If conditions are suitable, carry out flushing.

For sodium soils, use gypsum only by calculation.

Use salt-tolerant cover plants first.

Gradually accumulate organic matter.

Do not apply manure and mineral fertilizers without control.

Without drainage, flushing sometimes only raises salts closer to the surface or moves the problem to another location.

Separately: sands and shifting dunes

First line

branch lattices;

straw cages;

low permeable fences;

stripes across the wind.

Second line

local sand grasses;

rhizomatous cereals;

halophytes under salt influence;

ground cover shrubs.

Third line

larger shrubs;

trees only after partial stabilization;

water collection holes;

protection from sand drift.

Tall trees cannot be placed in the first line on a moving dune: their roots will be exposed or buried.

Separately: degraded pasture

Subsequence

Estimate the feeding capacity.

Reduce the livestock population.

Divide the territory into sectors.

Restore watering places.

Give the areas a long rest.

Sow native perennial grasses.

Add legumes.

Preserve shrub shelters.

Control weeds selectively.

Return animals only after the vegetation has taken root.

Grazing should follow plant recovery, not precede it.

Mosaic model of the restored landscape

An ideal system should not be completely identical.

It stores:

open steppe;

flowering meadows;

tall grass;

low grazing areas;

shrub islands;

forest belts;

wet depressions;

ponds;

stone areas;

dead wood;

areas without economic intervention;

productive forest gardens.

This mosaic provides more habitats than a continuous planting of one type.

Economic recovery sequence

Recovery must gradually pay for itself.

1st–2nd years

Possible products:

seeds and seedlings;

annual drought-resistant crops;

medicinal herbs;

hay;

compost;

water collection and nursery works.

2–5 years

perennial herbs;

managed grazing;

beekeeping;

berries;

forage plants;

biomass;

seeds of local herbs.

5-10 years

fruit crops;

early breed nuts;

medicinal raw materials;

mushrooms;

pasture-tree system;

Ecotourism.

10–30s

chestnut;

walnut;

valuable timber after thinning;

seed material;

processing;

a full-fledged forest garden;

paid ecosystem services.

Economic activity should not remove all biomass again. Some crops, grass, wood, and leaf litter should remain in the system.

Recovery benchmarks

It is necessary to measure not only the number of trees planted.

Soil

proportion of covered surface;

organic matter;

infiltration rate;

density;

root depth;

pH and salinity;

stability of units.

Water

reduction of surface runoff;

reduction of erosion;

duration of moisture retention;

groundwater level;

filling of seasonal reservoirs.

Vegetation

survival rate;

number of native species;

presence of perennials;

area of ​​bare land;

natural regeneration.

Animals

pollinators;

soil invertebrates;

birds;

amphibians;

small mammals.

Economy

costs per hectare;

volume of production;

need for watering;

forage productivity;

income by year;

number of jobs.

Sample plan for the first ten years

The timing depends heavily on precipitation. In a humid climate, some processes occur more quickly, while in arid climates, recovery can take decades.

The key principle of DREVO

It is not individual trees that need to be restored, butcycle:

rain → water penetration → living roots → microorganisms → plant matter → animals → organic matter → humus → new vegetation.

At the first stage, the human task is to stop water and soil loss. At the second stage, to restore permanent vegetation cover. At the third stage, to create a mosaic ecosystem. And only then should a forest garden, agricultural crops, and long-lived trees be introduced.

The most common mistake is planting expensive seedlings in unprepared, bare soil. The most sustainable approach is to first create conditions in which nature can once again grow plants almost independently.