EIACP Centre on Plants and Pollution

Waste Land Management through Plants

Source: http://ohvec.org/blog/wp-content/uploads/2006/02/3326.jpg

Waste Land :

Land is considered "degraded" when its productivity is diminished. This type of land is that land which is presently lying unused or which is not being used to its optimum potential due to some constraints. Land degradation caused by agriculture takes many forms and has many causes. Some of the most important types of land degradation are:

• Degradation related to overgrazing by livestock.
• Degradation related to soil erosion.
• Degradation attributable to soil salinization.
• Degradation attributable to waterlogging.

Classification of waste land:

National wastelands development board classifies wastelands into two categories:

Categories of Wastelands in India

Table-1

Category	Area (in sq.Kms.)
Snow Covered/Glacial	55788.49
Barren Rocky/Sheet Rock	64584.77
Sands-inland/coastal	50021.65
Land affected by salinity/alkalinity	20477.38
Gullied/or ravenous land	20553.35
Upland with or without scrub	194014.29
Water logged & Marshy	16568.45
Steep sloping area	7656.29
Shifting cultivation land	35142.20
Mining/Industrial Wastelands	1252.13
Degraded/pastures/grazing land	25978.91
Under utilized/degraded notified forest land	140652.31
Degraded land under plantation crop	5828.09

Causes of land degradation:

Following graph provides estimates of degraded land on the basis of the factors that caused the degradation.

Choice of Plant Species for Waste land Management:

Salt affected waste land have high content of soluble salt usually more than 0.2%, impossible for the plant to absorb water from saline soils. The soil pH value is generally between 7.3 and 8.5.

Plant species used for remediation:

• Suaeda salsa
• Kalidium folium
• Tetragonia tetragonioides
• Sesuvium portulacastrum
• Arthrocnemum indicum
• Suaeda frutic
• S. portulacastrum
• Suaeda maritime
• Sesuvium portulacastrum
• Atriplex etc

 

 

The above plants species analyzes the viability of using phytoremediation for salt affected soils and explores the remedial mechanisms involved.

Mining/Industrial waste land:

Surface mining (sometimes called quarrying or opencast mining) requires the removal of topsoil (the fertile layer of soil and organic matter that is particularly valuable for agriculture) to get at the valuable rocks below. Most metals, for example, occur in rocky mixtures called ores, from which the valuable elements have to be extracted by chemical, electrical, or other processes. That leaves behind waste products and the chemicals used to process them, which historically were simply dumped back on the land. Since all the waste was left in one place, the concentration of pollution often became dangerously high. Industrial activity generate waste which includes any material that is rendered useless during a manufacturing process such as chemical solvents, paints, sandpaper, paper products, industrial by-products, metals, and radioactive wastes.

Some more Plant species used for phytoremediation of contaminats present in wasteland :

Table-1

Grasses/Legumes Species/Common Name	Contaminant	Process	Comments
Agropyron smithii Western wheat grass	Hydrocarbons	Rhizodegradation	Perennial grass used in pastures / lawns; shown in studies to enhance degradation of TPH and PAHs in soils (McCutcheon & Schnoor, 2003).
Agrostis castellana Colonial bent grass	Metals	Hyper accumulation	Perennial A. castellana has been shown to accumulate As, Pb, Zn, Mn and Al.
Bouteloua gracilis Blue gamma grass	Hydrocarbons	Rhizodegradation	Used for low-water use lawn and pasture grass. Has shown promise in grass mixes to enhance degradation of PAHs in soils (McCutcheon & Schnoor, 2003).
Buchloe dactyloides Buffalo grass	Hydrocarbons	Rhizodegradation/ Accumulation	Perennial grass; low maintenance, drought tolerant lawn requiring little/no mowing. In studies has been shown to reduce TPH and PAHs in soil (McCutcheon & Schnoor,2003)
Cerastium arvense Field chickweed	Cadmium	Uptake/Accumulation	Tufted perennial, white flowers. A Northwest (NW) native, a recent study on Vashon Island indicated uptake of cadmium ( Institute for EnvironmentalResearch and Education, 2003). Additional chickweed varieties found in the NW include C. beringianum ( Bering chickweed ) and C. fi scherianum ( Fisher’s chickweed).
Claytonia perfoliata Miner’s lettuce	Cadmium	Uptake/Accumulation	A somewhat succulent annual with white or pink fl owers. Also known as Montia perfoliata. A smaller attractivevariety is Montia spathulata. A recent study on Vashon Island indicated uptake and accumulation of cadmium (Institute for Environmental Research and Education, 2003).
Cynodon dactylon Bermuda grass	Hydrocarbons	Rhizodegradation/Accumulation	Lawn grass; minimum maintenance but needs mowing and can be invasive. In studies where mixed with other grasses,it has reduced TPH and PAHs in soils (McCutcheon & Schnoor, 2003).
Elymus Canadensis Canadian wild rye	Hydrocarbon	Rhizodegradation/Accumulation	In combination with other grasses, was shown to reduce PAHs in soils (McCutcheon & Schnoor, 2003). E. mollis is a NW native wild rye
Festuca arundinacea Tall fescue	Pyrene, PAHs	Rhizodegradation/Phytoextraction	Introduced perennial grass common in the NW; studies have shown enhanced degradation of recalcitrant PAHs (Mcoutcheon, 2003)
Festuca rubra Red fescue	Hydrocarbons	Rhizodegradation	Perennial grass often used in lawn mixes; Studies have shown enhanced degradation of TPH and PAHs (McCutcheon & Schnoor, 2003).
Lolium perenne English ryegrass	Hydrocarbons/Nutrients	Rhizodegradation/Uptake	Perennial grass shown to uptake nutrients and to signifi cantly enhance degradation of TPH and PAHs in soils (McCutcheon & Schnoor, 2003).
Lupinus albus White lupin	Arsenic	Rhizoaccumulation	Nitrogen fixing legume capable of growth in acidic soils with low nutrient availability. A recent study indicated an ability to take up arsenic, primarily stored in the root structure (Esteban, Vazquez & Carpena, 2003). A number of lupine varieties are native to the NW, including: Lupinus arcticus (Artic lupine), L. littoralis (Seashore lupin), L. nootkatensis (Nootka lupine), and L. polyphyllus (Large-leaved lupine).
Lotus corniculatus Birds-foot trefoi	Hydrocarbon	Rhizodegradation/Accumulation	An introduced European annual herb; when mixed with grasses was shown to reduce TPH and PAHs in soils (McCutcheon & Schnoor, 2003). This plant is generally not recommended for introduction into constructed wetlands of the Puget Sound region (Azous & Horner, 2001).

Source:http://www.superorg.net/archive/proposal/plant%20species%20phyto.pdf

Wasteland Development Schemes:

Till the sixth five year plan, no specific programme of wasteland development was taken up. It is only in1985 with establishment of NWDB that the problem of wasteland development received a new thrust. With the setting up of NWDB, a number of new schemes were initiated to secure people‘s participation, besides continuation of ongoing afforestation schemes.

These are: Grants-in-aid to voluntary agencies:

• Decentralized People’s nurseries
• Silvipasture farms
• Seed development
• Area oriented fuel wood and fodder projects
• Ariel seeding programme
• Plantation of minor forest produce
• Margin money schemes
• Rural employment scheme

Major Ongoing Project:

IWDP (Integrated wasteland development Project) Scheme-This scheme is under implementation since 1989-90, and has come to this Department along with the National Wastelands Development Board. The development of non-forest wastelands is taken up under this Scheme. The scheme provides for the development of an entire micro watershed in an holistic manner rather than piecemeal treatment in sporadic patches.. The thrust of the scheme continues to be on development of wastelands.

Objectives:

The basic objective of this scheme is an integrated wastelands development based on village/micro watershed plans. These plans are prepared after taking into consideration the land capability, site condition and local needs of the people. The scheme also aims at rural employment besides enhancing the contents of people's participation in the wastelands development programmes at all stages, which is ensured by providing modalities for equitable and sustainable sharing of benefits and usufructs arising from such projects.

Activities: The major activities taken up under the scheme are:

• In situ soil and moisture conservation measures like terracing, bunding, trenching, vegetative barriers and drainage line treatment.
• Planting and sowing of multi-purpose trees, shrubs, grasses, legumes and pasture land development.
• Encouraging natural regeneration.
• Promotion of agro-forestry & horticulture.
• Wood substitution and fuel wood conservation measures.
• Awareness raising, training & extension.
• Encouraging people's participation through community organization and capacity building.
• Drainage Line treatment by vegetative and engineering structures.
• Development of small water Harvesting Structures.
• Afforestation of degraded forest and non forest wasteland.
• Development and conservation of common Property Resources.

Source:http://environmanagementbitkolkata

Modified strategies and suggestions:

Keeping in view the lesson learnt the following suggestions need to be considered while revising strategy.

• Govt. departments must view afforestation as a definite support to agriculture, e.g. shelterbelts, agro forestry, mixed plantation etc.
• People’s involvement can be mobilized by understanding the community structure and their needs.
• Sufficient funds should be earmarked and made available to finance projects aimed at integrated rural resource management which are multi disciplinary in nature at every stages.
• Banks like NABARD should establish a separate line of credit for afforestation projects.
• Suitable action plan should be taken up for integrated development of wastelands for ecological restoration and to meet essential needs of fuel wood, fodder and timber for local community.
• The lab to land programme should seek to extensively popularize transfer of available technologies.
• All development projects e.g. mining, road, irrigation and power etc. which by their very nature either create wastelands or degraded local environment should earmark a budget provision in the project estimates for reclaiming such wastelands or regenerating natural vegetation so damaged.

Source:http://environmanagementbitkolkata.blogspot.in/2012/10/wasteland-reclamation.html