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Nina M. CadizInstitute of Biological Sciences
University of the Philippines Los Baños
Translocation of Heavy Metals in Jatropha curcas (Physic Nut)
Grown in Abandoned Mine Area
UPLB BASIC RESEARCH- Fund Code: 88-D60-23
Study presented on March 30, 2010, OVCRE, UPLB
Once metals are introduced and contaminate the environment, they will remain.
In general it is very difficult to eliminate metals from the environment. Metals are not degraded easily.
However, concentration in the soil may be reduced.
Heavy metal pollutated areas need REHAB!
BACKGROUND…
Excess heavy metal accumulation in soils is toxic to humans and other animals.Exposure to heavy metals is normally chronic due to food chain transfer.Chronic problems associated with long-term heavy metal exposures are:
•Lead – mental lapses•Cadmium – affects kidney, liver, and GI tract•Arsenic – skin poisoning, affects kidneys and central nervous system.
Heavy metal pollutated areas need REHAB!
Need:
Management of Contaminated Soil by carefully selecting plants for use on metal-contaminated soils
Why Jatropha?
Hype on Jatropha as cheap source of biodiesel
Lead to exhaustive research and massive planting of Jatropha
http://www.jatropha.de/news/jcl-news.htm
Oasis in the desert: Jatropha cultivation can halt soil erosion, increase water storage in the soil and transform barren expanses into lush, productive land.
My inspiration:
Questions:
Can Jatropha be used as a phytoremediation species?
Can it grow well in abandoned mine areas, for instance?
Would it translocate the heavy metals (HMs) to the fruits?
If YES, this then would be an environmental concern since seeds are processed for biodiesel – magnify problem of HM pollution
The main objective of the study is to look into the heavy metal (HM) uptake and translocation in Jatropha curcas.
Specific Objectives
1. Assess the adaptability of J. curcas in the
abandoned mine area of Mogpog, Marinduque
2. Determine the translocation of heavy metals to
various plant organs of Jatropha up to the fruiting
stage
3. Assess the effects of some mitigating measures to
regulate the transport of heavy metals using microbial
amendment in the form of mycorrhiza.
THE STUDY AREA
Satellite image of the 32 hectares abandoned mine site
(Cu mining) in Mogpog, Marinduque(Source: http://maps.google.com.2009)
Experimental site in Brgy. Capayang, Mogpog, Marinduque
Experimental site in Brgy. Capayang, Mogpog, Marinduque
Part 1. Growth assessment of Jatrophaoutplanted in Mogpog, Marinduque
Treatment Height(cm)
Diameter(cm)
Uninoculated 3.88 b 0.231 c
MykoVAM 4.55 ab 0.554 bc
MineVAM 4.33 b 0.503 bc
Table 1. Growth of J. curcas treated mycorrhiza three months after transplanting in an abandoned mine site in Barangay Capayang, Mogpog, Marinduque.
0
5
10
15
20
25
30
Height (cm)
Control MykoVAM MineVAM
Treatments
Height of Jatropha outplanted in an abandoned mine site in Mogpog,
Marinduque 10 mos after establishment.
10.5
11
11.5
12
12.5
Diameter (cm)
Control MykoVAM MineVAM
Treatments
Diameter (cm) of Jatropha outplanted in abandoned mine site in Mogpog,
Marinduque 10 mos after establishment.
Height not improved as compared with the control.
Diameter not improved as compared with the control.
Part 2. Translocation of heavy metals in Jatropha curcasgrown in abandoned mine site in Mogpog, Marinduque
Treatments
Heavy
Metals A. Roots B. Stems C. Leaves
Uninoculated Copper 57.175 60.971 24.664
Zinc 26.119 8.636 4.925
Cadmium 0.000 0.000 0.161
Lead 13.346 17.077 28.161
+MykoVAM Copper 63.948 42.194 23.403
Zinc 17.343 6.655 13.689
Cadmium 0.000 0.000 0.000
Lead 17.661 8.539 9.498
+MineVAM Copper 56.756 34.535 42.867
Zinc 18.942 5.319 0.727
Cadmium 0.000 0.000 0.000
Lead 2.949 9.039 10.917
Table 1. Concentration (mg/kg) of copper, zinc, cadmium and lead (mg/kg) of Jatropha roots, stems and leaves grown in Mogpog, Marinduque. Values are averages of three replicates.
Plant Organ
Uninoculated (Control)
Inoculated(MykoVAM & Mine VAM)
Roots Zn Cu, Pb, Zn
Stems Cu
Leaves Pb, Cd (but very very
low concentration)
Pb (highest with
MineVAM)
Fruits None None
Metal Translocation(Plant organ with highest HM concentration)
In general, translocation of HMs to upper parts was regulated by mycorrhizal treatments.
Possible reason:
Mycorrhiza also absorbed the HMs thus reduced translocation to upper plant organs.
Metal translocation: (Inoculated)
Cadmium (Cd) uptake
Nil to zero
Possible reason:
Very low Cd concentration in the soil based on initial analysis.
Fruit Analysis
Analysis of fruits collected from vicinity of various abandoned mine areas in the Philippines (including Mogpog) showed negative HM concentration.
Reason: Plants translocate larger quantities of metals to their leaves than to their fruits or seeds.
Implication: Greater risk of food chain contamination since forage is eaten by livestock.
CONCLUSION:
Are HMs translocated in Jatropha fruits?
No.
Can Jatropha grow in abandoned mine or HM-polluted areas?
Yes, provided that soil amendments are placed.
Is Jatropha a good phytoremediation species?
No.
FUTURE PROSPECTS
Phytoremediation is an excellent green-technology to cleanup heavy metal contaminated areas.
Further research is needed to look for ways of regulating HM translocation to the aerial parts of the plants to assure that tissues of plants used for phytoremediation do not have adverse environmental effects if eaten by wildlife or used by humans (e.g. mulch or firewood)
Research is also needed to find more efficient bioaccumulators, hyperaccumulators that produce more biomass.
Acknowledgement
OVCRE-UPLB for funding the research
Collaborators in Mogpog, Marinduque
LGU – Mayor Libello
Capayang Elementary School
DENR, Marinduque
Thank you for listening....
Potentially contaminated soils may occur at: old landfill sites
old orchards that used insecticides containing arsenic as an active ingredient
fields that had past applications of waste water or municipal sludge
areas in or around mining waste piles and tailings
industrial areas where chemicals may have been dumped on the ground, or
in areas downwind from industrial sites
Phytoextraction Process of growing plants in metal
contaminated soil .
Plant roots translocate the metals into aboveground portions of the plant.
After plants have grown for some time, they are harvested and incinerated or composted to recycle the metals. Several crop growth cycles may be needed to decrease contaminant levels to allowable limits.
If the plants are incinerated, the ash must be disposed of in a hazardous waste landfill.
Volume of the ash is much smaller than the volume of contaminated soil if dug out and removed for treatment.
Sources of Heavy Metal in Soils
Mining, manufacturing, and the use of synthetic products (e.g. pesticides, paints, batteries, industrial waste, and land application of industrial or domestic sludge)
Heavy metals also occur naturally, but rarely at toxic levels.
The most common problem causing cationic metals (metallic elements whose forms in soil are positively charged cations e.g., Pb2+) are mercury, cadmium, lead, nickel, copper, zinc, chromium, and manganese.
The most common anionic compounds (elements whose forms in soil are combined with oxygen and are negatively charged e.g., MoO42-) are arsenic, molybdenum, selenium, and boron.
Phytoextraction Plant roots translocate the metals into
aboveground portions of the plant.
After plants have grown for some time –
harvested and incinerated or composted to recycle the metals.
If the plants are incinerated, the ash must be disposed of in a hazardous waste landfill.
Volume of the ash is much smaller than the volume of contaminated soil if dug out and removed for treatment.
Block Copper (mg/kg)
Cadmium (mg/kg)
Lead (mg/kg)
Zinc (mg/kg)
Block 1 84.95 ± 0.63 0.033 0.399 4.532 ±0.015
Block 2 71.60 ± 2.28 0.022 0.941 4.752 ±0.174
Block 3 56.36 ± 0.33 0.022 0.694 3.656 ±0.024
MEAN 70.97 ±1.08 0.026 0.678 4.313±0.071
Table 2. Initial heavy metal analyses of soil collected in Mogpog, Marinduque. (reported during the 1st year of operation).
Element Target value
(mg kg-1 soil)
Intervention
value*
(mg kg-1 soil)
Cadmium 0.8 12
Copper 36 190
Mercury 0.3 10
Lead 85 530
Zinc 140 720
Dutch standards for soil contamination
assessment, in terms of total concentration
of heavy metals in soils.
*Intervention value - This indicates serious contamination of soils where
remediation is necessary.
Treating metal contaminants
By phytoextraction, rhizofiltration
and/or phytostabilization