Planting a Halophyte (Sporobolus virginicus, "Dixie grass") to rehabilitate severely saline soil. (Pirach Pongwichian)

Planting a Halophyte (Sporobolus virginicus, "Dixie grass") to rehabilitate severely saline soil. (Thailand)

Planting Dixie grass in severely saline soil.

Description

Planting a halophyte - Dixie grass (Sporobolus verginicus) - aims to increase the area of land usable by farmers and to prevent expansion of severely saline soils. Dixie grass can be utilised as cattle feed. The Land Development Department has been involved in developing and disseminating this technology.

The Land Development Department (LDD) transfered the technology of planting a halophyte (Sporobolus virginicus: "Dixie grass") for the rehabilitation of severely saline soil to Mr.Charong Munkarn’s land in Buayai district, Nakhonratchasima province. The area is on a 0-2% slope, demonstrates high soil electrical conductivity and is classified as a severely saline soil. The land is salt crusted and barren. The climate is semi -arid, and rainfall is between 750 and 1,000 millimeters per year. The exotic halophyte, namely Sporobolus virginicus, (Dixie grass) is adapted to survive in severely salt- affected soil. The mechanisms of its tolerance includes osmotic adjustment within the plant, salt exclusion, ion accumulation and sequestration, and excretion of salt via glands in the plant’s leafs and stem. The benefits of planting this halophyte on such a severely saline soil are soil moisture conservation, salt accumulation prevention on the surface, and utilization as feed for livestock. The objectives of the technology are to 1) prevent expansion of severely saline soil, 2) maximize use of land for farmers, 3) use halophyte grasses as cover crop for rehabilitation of the ecosystem of severely salt-affected soil. Halophyte plantation has been supported by Land Development Department under the project: Promotion of Integrated Saline Soil Management. The stakeholders are researchers of LDD who have worked together with community volunteers, community leaders and farmers on soil improvement. The Land Development Regional Office 3 (Nakhonratchasima) supported Dixie grass planting material production, together with provision of compost and chemical fertilizer. Dixie grass cuttings (stolons) were planted at spacing of 20 x 20 centimeters on abandoned areas and on ridges between rows of Acacia ampliceps. After 3 years of planting Dixie grass, it has been found that this barren land was covered by plants and much improved in biodiversity by the evidence of many varieties of wild grass, dragonflies, small mammels and birds. Farmers can grow rice and they use Dixie grass as feed for livestock. Moreover farmers are able to increased their incomes. Migration for jobs to big cities has been reduced. Interviews showed that farmers are satisfied with this technology. Besides being lower in salinity (observed, and measured by scientists), farmers get better rice yields, and an improved environment and livelihoods. Although the planting of halophytes is an improvement to severely saline soil with low costs, the recovery time of saline soil is not as fast as that of engineering measure with higher investment. Furthermore, neighboring farmers often burn their rice straw after harvesting, and that damages the Dixie grass.

Location

Location: Bann Donpae, 6 Bann Donpae Moo 8 Kut Chok Sub-district Bua Yai District Nakhon Ratchasima Province., Thailand

No. of Technology sites analysed: single site

Geo-reference of selected sites
  • 102.47748, 15.55688

Spread of the Technology: applied at specific points/ concentrated on a small area

In a permanently protected area?: No

Date of implementation: 2015; less than 10 years ago (recently)

Type of introduction
Overview : planting the halophyte, Sporobolus virginicus (Dixie grass) to rehabilitate severely saline soil. (Jutharat Ratanapunya)
The mechanism of salt tolerance ; excretion of salt (taken up by the roots) via glands in plant leafs. (Kamontip Sasithorn)

Classification of the Technology

Main purpose
  • improve production
  • reduce, prevent, restore land degradation
  • conserve ecosystem
  • protect a watershed/ downstream areas – in combination with other Technologies
  • preserve/ improve biodiversity
  • reduce risk of disasters
  • adapt to climate change/ extremes and its impacts
  • mitigate climate change and its impacts
  • create beneficial economic impact
  • create beneficial social impact
Land use
Land use mixed within the same land unit: Yes - Agro-pastoralism (incl. integrated crop-livestock)

  • Other - Specify: Extremely salt affected areas
    Remarks: Extremely salt affected areas that can not used for agricultural land.
Water supply
  • rainfed
  • mixed rainfed-irrigated
  • full irrigation

Purpose related to land degradation
  • prevent land degradation
  • reduce land degradation
  • restore/ rehabilitate severely degraded land
  • adapt to land degradation
  • not applicable
Degradation addressed
  • chemical soil deterioration - Cs: salinization/ alkalinization
SLM group
  • pastoralism and grazing land management
  • improved ground/ vegetation cover
  • ecosystem-based disaster risk reduction
SLM measures
  • vegetative measures - V2: Grasses and perennial herbaceous plants, V5: Others

Technical drawing

Technical specifications
(a) Propagation of Dixie grass through shoot (stolon) cuttings of 2-3 inches long with
3 nodes is made and planted in bags filled with soil and compost. The seedling
is 1 month old before planting in the pit of 10x10x10 cubic cm. with 200 gm. of
compost and 6.25 gm of 15-15-15 chemical fertilizer then cover with rice husk
at 400 gm/pit, the spacing between pits is 30x30 square cm.

(b) A sketch of planting Dixie grasses on severely salt affected land with
Acacia ampliceps on the ridges. After 3 years of planting, Dixie grass
has been replaced by rice except those on the ridge.
Author: Winai Chombut

Establishment and maintenance: activities, inputs and costs

Calculation of inputs and costs
  • Costs are calculated: per Technology area
  • Currency used for cost calculation: Baht
  • Exchange rate (to USD): 1 USD = 32.0 Baht
  • Average wage cost of hired labour per day: 300
Most important factors affecting the costs
The government policy on minimum labor wage is an important factor affected cost of the project.
Establishment activities
  1. Dixie grass nursery (Timing/ frequency: May-July 2015)
  2. Land preparation for planting (Timing/ frequency: May-July 2015)
  3. Fertilizer application (Timing/ frequency: May-July 2015)
Establishment inputs and costs
Specify input Unit Quantity Costs per Unit (Baht) Total costs per input (Baht) % of costs borne by land users
Labour
Labor cost for planting Eucalyptus (labor wage per day = 300 baht, 1 rai required to labor cost = 1200 baht) Rai 1.0 1200.0 1200.0
Plant material
Dixie seedling cost 1600 trees/rai, 1 baht for each seedling seedling 1600.0 0.5 800.0
Fertilizers and biocides
Compost cost 3.5 baht/kg, 0.2 kg/pit kg 320.0 3.5 1120.0
Rice husk cost 4 baht/kg, 0.4 kg/pit kg 640.0 4.0 2560.0
Chemical fertilizer 15-15-15 cost 20 baht/kg, 6.25 kg/pit kg 10.0 20.0 200.0
Total costs for establishment of the Technology 5'880.0
Total costs for establishment of the Technology in USD 183.75
Maintenance activities
  1. No maintenance activities because Dixies grasses can glow well and be multiplied extensively by themselves (Timing/ frequency: None)
Maintenance inputs and costs
Specify input Unit Quantity Costs per Unit (Baht) Total costs per input (Baht) % of costs borne by land users
Labour
No labor cost for maintenance 0

Natural environment

Average annual rainfall
  • < 250 mm
  • 251-500 mm
  • 501-750 mm
  • 751-1,000 mm
  • 1,001-1,500 mm
  • 1,501-2,000 mm
  • 2,001-3,000 mm
  • 3,001-4,000 mm
  • > 4,000 mm
Agro-climatic zone
  • humid
  • sub-humid
  • semi-arid
  • arid
Specifications on climate
Average annual rainfall in mm: 1028.0
Average annual rainfall from 1983-2012
Name of the meteorological station: Meteorological Department
Average temperature 21 - 36 degree Celsius, relative humidity is 75%
Slope
  • flat (0-2%)
  • gentle (3-5%)
  • moderate (6-10%)
  • rolling (11-15%)
  • hilly (16-30%)
  • steep (31-60%)
  • very steep (>60%)
Landforms
  • plateau/plains
  • ridges
  • mountain slopes
  • hill slopes
  • footslopes
  • valley floors
Altitude
  • 0-100 m a.s.l.
  • 101-500 m a.s.l.
  • 501-1,000 m a.s.l.
  • 1,001-1,500 m a.s.l.
  • 1,501-2,000 m a.s.l.
  • 2,001-2,500 m a.s.l.
  • 2,501-3,000 m a.s.l.
  • 3,001-4,000 m a.s.l.
  • > 4,000 m a.s.l.
Technology is applied in
  • convex situations
  • concave situations
  • not relevant
Soil depth
  • very shallow (0-20 cm)
  • shallow (21-50 cm)
  • moderately deep (51-80 cm)
  • deep (81-120 cm)
  • very deep (> 120 cm)
Soil texture (topsoil)
  • coarse/ light (sandy)
  • medium (loamy, silty)
  • fine/ heavy (clay)
Soil texture (> 20 cm below surface)
  • coarse/ light (sandy)
  • medium (loamy, silty)
  • fine/ heavy (clay)
Topsoil organic matter content
  • high (>3%)
  • medium (1-3%)
  • low (<1%)
Groundwater table
  • on surface
  • < 5 m
  • 5-50 m
  • > 50 m
Availability of surface water
  • excess
  • good
  • medium
  • poor/ none
Water quality (untreated)
  • good drinking water
  • poor drinking water (treatment required)
  • for agricultural use only (irrigation)
  • unusable
Water quality refers to:
Is salinity a problem?
  • Yes
  • No

Occurrence of flooding
  • Yes
  • No
Species diversity
  • high
  • medium
  • low
Habitat diversity
  • high
  • medium
  • low

Characteristics of land users applying the Technology

Market orientation
  • subsistence (self-supply)
  • mixed (subsistence/ commercial)
  • commercial/ market
Off-farm income
  • less than 10% of all income
  • 10-50% of all income
  • > 50% of all income
Relative level of wealth
  • very poor
  • poor
  • average
  • rich
  • very rich
Level of mechanization
  • manual work
  • animal traction
  • mechanized/ motorized
Sedentary or nomadic
  • Sedentary
  • Semi-nomadic
  • Nomadic
Individuals or groups
  • individual/ household
  • groups/ community
  • cooperative
  • employee (company, government)
Gender
  • women
  • men
Age
  • children
  • youth
  • middle-aged
  • elderly
Area used per household
  • < 0.5 ha
  • 0.5-1 ha
  • 1-2 ha
  • 2-5 ha
  • 5-15 ha
  • 15-50 ha
  • 50-100 ha
  • 100-500 ha
  • 500-1,000 ha
  • 1,000-10,000 ha
  • > 10,000 ha
Scale
  • small-scale
  • medium-scale
  • large-scale
Land ownership
  • state
  • company
  • communal/ village
  • group
  • individual, not titled
  • individual, titled
Land use rights
  • open access (unorganized)
  • communal (organized)
  • leased
  • individual
Water use rights
  • open access (unorganized)
  • communal (organized)
  • leased
  • individual
  • Rainfed
Access to services and infrastructure
health

poor
x
good
education

poor
x
good
technical assistance

poor
x
good
employment (e.g. off-farm)

poor
x
good
markets

poor
x
good
energy

poor
x
good
roads and transport

poor
x
good
drinking water and sanitation

poor
x
good
financial services

poor
x
good

Impacts

Socio-economic impacts
Crop production
decreased
x
increased

crop quality
decreased
x
increased

fodder production
decreased
x
increased

risk of production failure
increased
x
decreased

production area (new land under cultivation/ use)
decreased
x
increased

land management
hindered
x
simplified

drinking water availability
decreased
x
increased

drinking water quality
decreased
x
increased

water availability for livestock
decreased
x
increased

water quality for livestock
decreased
x
increased

irrigation water availability
decreased
x
increased

irrigation water quality
decreased
x
increased

demand for irrigation water
increased
x
decreased

expenses on agricultural inputs
increased
x
decreased

farm income
decreased
x
increased

diversity of income sources
decreased
x
increased

workload
increased
x
decreased

Socio-cultural impacts
food security/ self-sufficiency
reduced
x
improved

health situation
worsened
x
improved

land use/ water rights
worsened
x
improved

cultural opportunities (eg spiritual, aesthetic, others)
reduced
x
improved

community institutions
weakened
x
strengthened

national institutions
weakened
x
strengthened

SLM/ land degradation knowledge
reduced
x
improved

conflict mitigation
worsened
x
improved

situation of socially and economically disadvantaged groups (gender, age, status, ehtnicity etc.)
worsened
x
improved

Ecological impacts
water quantity
decreased
x
increased

water quality
decreased
x
increased

harvesting/ collection of water (runoff, dew, snow, etc)
reduced
x
improved

surface runoff
increased
x
decreased

excess water drainage
reduced
x
improved

groundwater table/ aquifer
lowered
x
recharge

evaporation
increased
x
decreased

soil moisture
decreased
x
increased

soil cover
reduced
x
improved

soil loss
increased
x
decreased

soil accumulation
decreased
x
increased

soil crusting/ sealing
increased
x
reduced

soil compaction
increased
x
reduced

nutrient cycling/ recharge
decreased
x
increased

salinity
increased
x
decreased

soil organic matter/ below ground C
decreased
x
increased

acidity
increased
x
reduced

vegetation cover
decreased
x
increased

biomass/ above ground C
decreased
x
increased

plant diversity
decreased
x
increased

invasive alien species
increased
x
reduced

animal diversity
decreased
x
increased

beneficial species (predators, earthworms, pollinators)
decreased
x
increased

habitat diversity
decreased
x
increased

pest/ disease control
decreased
x
increased

flood impacts
increased
x
decreased

landslides/ debris flows
increased
x
decreased

drought impacts
increased
x
decreased

impacts of cyclones, rain storms
increased
x
decreased

emission of carbon and greenhouse gases
increased
x
decreased

fire risk
increased
x
decreased

wind velocity
increased
x
decreased

micro-climate
worsened
x
improved

Off-site impacts
water availability (groundwater, springs)
decreased
x
increased

reliable and stable stream flows in dry season (incl. low flows)
reduced
x
increased

downstream flooding (undesired)
increased
x
reduced

downstream siltation
increased
x
decreased

groundwater/ river pollution
increased
x
reduced

buffering/ filtering capacity (by soil, vegetation, wetlands)
reduced
x
improved

wind transported sediments
increased
x
reduced

damage on neighbours' fields
increased
x
reduced

damage on public/ private infrastructure
increased
x
reduced

impact of greenhouse gases
increased
x
reduced

Cost-benefit analysis

Benefits compared with establishment costs
Short-term returns
very negative
x
very positive

Long-term returns
very negative
x
very positive

Benefits compared with maintenance costs
Short-term returns
very negative
x
very positive

Long-term returns
very negative
x
very positive

Climate change

Climate-related extremes (disasters)
drought

not well at all
x
very well
forest fire

not well at all
x
very well
land fire

not well at all
x
very well
flash flood

not well at all
x
very well
insect/ worm infestation

not well at all
x
very well
Other climate-related consequences
extended growing period

not well at all
x
very well
reduced growing period

not well at all
x
very well

Adoption and adaptation

Percentage of land users in the area who have adopted the Technology
  • single cases/ experimental
  • 1-10%
  • 11-50%
  • > 50%
Of all those who have adopted the Technology, how many have done so without receiving material incentives?
  • 0-10%
  • 11-50%
  • 51-90%
  • 91-100%
Has the Technology been modified recently to adapt to changing conditions?
  • Yes
  • No
To which changing conditions?
  • climatic change/ extremes
  • changing markets
  • labour availability (e.g. due to migration)

Conclusions and lessons learnt

Strengths: land user's view
  • Dixie grass is very highly salt tolerant and after planting the salinity obviously decreased.
  • The better environment that encourages the return of other plant species.
  • Secondly instead of leaving the land barren the land user can sell the Dixie shoots for propagation to Land Development Department.
Strengths: compiler’s or other key resource person’s view
  • Only halophytes especially Dixie can grow well on severely salt affected land.
  • After planting Dixie for few years, the soils are less saline that induces biodiversity of both fauna and flora such as birds butterflies, rats, earthworms and native flowers.
  • The farmers can use their land more extensively rather than leave it barren.
  • Dixie grasses can be used as cattle feed that the land user can get higher incomes.
Weaknesses/ disadvantages/ risks: land user's viewhow to overcome
  • The land user lack of knowledge on halophytes and there is no other choice for better income than Dixie grass. The SLM officers should visit them and provide better knowledge.
  • The neighboring farmers get used to the burning of rice straw after harvest causing death of Dixie grass nearby. Public relation is needed to stop burning.
Weaknesses/ disadvantages/ risks: compiler’s or other key resource person’s viewhow to overcome
  • Not all the researchers and SLM workers understand the mechanism of halophyte and the importance of the Dixie grass to the project flow chart’s work plans. They need to be well trained at various levels.
  • The farmers are not well approached and many of them know nothing about the project. The officers should be trained and get better knowledge about the project.
  • The project follows up and evaluation is insufficient and ineffective. The concerned project officers should pay more awareness on weakness and on obstacles of the success of the project.

References

Compiler
  • Kamontip Sasithorn
Editors
Reviewer
  • Rima Mekdaschi Studer
  • William Critchley
Date of documentation: Oct. 30, 2018
Last update: Dec. 29, 2020
Resource persons
Full description in the WOCAT database
Linked SLM data
Documentation was faciliated by
Institution Project
Key references
  • Land Development Department: http://www.ldd.go.th/
Links to relevant information which is available online
This work is licensed under Creative Commons Attribution-NonCommercial-ShareaAlike 4.0 International