66 The graphic showed that treatment C 9.2
– 9.3 O
2
and D 5.9 – 6.1 O
2
have the lowest weight loss than the other treatment applied with highest weight loss point at 0.47 and 0.49. But graphic D showed that the
weight loss occurred was slower than the other. While graphic E using the lowest O
2
concentration showed that it reach faster at the same weight loss point, so it may caused by varicosity of the fruit used in experiments.
However, it can be conclude that the lower O
2
concentration used in storage can retard Sapodilla fruit weight loss. It was the same result as [4], exhibited
that O
2
concentration in the modified atmosphere storage affect the retarding of respiration activity, so the breaking process of carbohydrates
into volatile compounds can be retarded.
4. Conclusion
The concentration of O2 inside the storage room at modified atmosphere storage methods at room temperature, affect the rate of O2 uptake of
Sapodilla fruit. Rate of O2 uptake at respiration process was decrease comparable with the lower O2 concentration used at storage room. But the
concentration of O2 relatively has no effect toward CO2 production rate at respiration process.
Maturity time of Sapodilla fruit is affected by the amount of O2 concentration in storage room. The lower O2 concentration used inside
storage room is able to retard maturity and extend the shelf life of Sapodilla fruit.
5. References
[1] L.C. Hawa. 2005. Kajian susut berat dan pengembangan model laju respirasi buah sawo Achras zapota L. dalam penyimpanan
hipobarik. J. of Agric. Technol. Vol. 6 No. 2. [2] R. Hartanto, A. Jasman. 2009. Perubahan kimia, fisika dan lama
simpan buah sawo Achras zapota L. dalam penyimpanan atmosfir termodifikasi. Lokakarya Grassroot Innovation GRI. Lampung
University. Bandar Lampung
[3] E. Sudarminto. 1λλ2. Mempelajari pengaruh “modified atmosphere
packaging ” terhadap masa simpan alpukat Persea americana, Mill.
Institut Pertanian Bogor, Bogor. [4] A.A. Kader. 1985. Modified Atmospheres. An Indexed Reference List
With Emphasis On Horticultural Commodities, Supplement No. 4. Postharvest Horticulture Series3, University of California. California.
67
Heavy metals and other elements concentration in Emilia
sonchifolia grown in topand overburden of Serpentine soil from Sorowako, Indonesia
A. Tjoa
1,
, H. Barus
1
1
Agriculture Faculty, Tadulako University, Indonesia
Corresponding author: aiyenbyahoo.comaiyenuntad.ac.id
Abstract
Building a phytomining field on overburden waste material without laid it with top soil is the aim of the commercial phytomining.
Developing commercial phytomining on this overburden will consequently lower the operational cost. Few compositae species have a good adaptation
in ultramafic sites such as Emilia sonchifolia in Sorowako and accumulate 190-280 mg kg
-1
of Ni. A pot experiment was conducted to test the efficacy of E.sonchifolia to acquire Ni and others elements from top and overburden
soils of ultramafic Limonitic and saprolitic Laterite treated with and without chicken manure ww 1 g kg
-1
. Total Ni concentration in the topsoil, limonitic and saprolitic laterite were 7.051, 7.884, 10.524 mg kg
-1
, respectively. The shoots were collected at 50 days after transplanting, and
measured for their Ni, Cr, Zn, Fe, K and Mg. Emilia sp produced significantly higher shoot dried biomass and contained higher Zn
concentration when grown in topsoil on both treatments. But Ni, Cr and Mg concentrations and contents were higher in saprolitic laterite. Ni
concentration in manure treated topsoil, limonitic and saprolitic laterite was 12.5, 30.7 and 254.5 mg kg
-1
and the non treated 14.7, 29.7 and 210.7 mg kg
-1
, respectively. Fe was the only element that reduced when chicken manure was applied. Potassium concentration and content were not
different in all soils and treatments. Although E.sonchifolia produced 2-5 folds greater shoots when grown in topsoil and limonitic, but Ni removal
rate was higher in saprolitic overburden due to much higher of Ni concentration in this soil.
Keywords
heavy metal, top soil, overburden, ultrabasic, Emilia sp
1. Introduction
Ultramafics containing nickel laterites are found mainly in Central and Eastern Sulawesi, with a combined area in excess of 8,000 km
2
. The lateritic soils are rich in nickel and commonly strip-mined in Central Sulawesi.
Globally, nickel deposits are found in either sulphide 40 of world
68 reserves or lateritic ultramafic deposits 60 of world reserves with
some of the largest reserves in nickel laterites in Indonesia, Cuba, New Caledonia and Australia. The U.S. Geological Survey 2010 estimates the
nickel reserves at 7.1 Mt for New Caledonia, 3.2 Mt for Indonesia and 26 Mt for Australia, with 2009 productions of 107,000, 189,000 and 167,000 t
of nickel respectively. High-grade sulphide deposits are depleting, and as a result a higher proportion of future production is expected to come from
laterite deposits [1]. Historically, nickel laterites were very difficulty to
process but with the development of the ‘high pressure acid leach’ HPAL technology lateritic ores have become profitable [1]. Retrieving nickel from
laterites is energy intensive and produces large volumes of waste rock. In 2008, a total 86,000 t of nickel was produced from 4.7 Mt of saprolitic ore
in New Caledonia [2]. Phytoremediation is an emerging technology that uses specific plants to
degrade, extract, or immobilize contaminants from soil and water. This technology has been receiving increasing attention lately as an innovative,
cost-effective, and alternative to the more established physical treatment methods used at hazardous waste sites. Phytoremediation approaches
generally fall into four categories, one of which is phytoextraction. Phytoextraction is the use of hyperaccumulating plants to remove toxic
substances such as heavy metals from the soil and store them in their shoots [3]. The interest in phytoextraction has grown significantly following the
identification of metal hyperaccumulator plant species, which can contain as much as 5 metal on a dry weight base. An ability to predict the
efficiency of phytoextration from a particular soil as well as finding super hyperaccumulator plants is crucial to decide upon the commercial
application of these technology. Ultramafic soils differed from the non-ultramafic soils in texture, having a
higher proportion of clay and silt. Soils derived from ultramafic bedrock have a number of extreme chemical properties that challenge plants to
survive, which include a deficiency in the macronutrients phosphorus, potassium, calcium, and nitrogen, and unusually high concentrations of
magnesium and nickel which may act as toxins [4, 5]. Soil profile is made up of a number of layers likewise ultramafic, including the topsoil and
overburden layers. In Sorowako, topsoil layer usually about 0-15 cm contains a large store of seed and nutrients in comparison to other layers
that are vital to the success of the future mine rehabilitation. The overburden layer is 30-100 cm of gravely sub-soil material sitting above the caprock.
Before mining can begin, the topsoil and overburden are removed
