PHYTO-REMEDIATION FOR REHABILITATION OF AGRICULTURAL LAND CONTAMINATED BY CADMIUM AND COPPER 1)

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1 Phyto-remediation Indonesian Journal for of rehabilitation Agriculture 4(1), of agricultural 211: land PHYTO-REMEDIATION FOR REHABILITATION OF AGRICULTURAL LAND CONTAMINATED BY CADMIUM AND COPPER 1) N. Sutrisno Sa ad, R. Artanti, and T. Dewi Indonesian Agricultural Environment Research Institute Jalan Raya Jakenan, Jaken km 5, PO Box 5, Jaken, Pati 59182, Phone: , Facs.: ABSTRACT Farmers in some areas in Indonesia use industrial waste water contaminated by heavy metals to irrigate rice field. To overcome the heavy metal contamination, improvement of agricultural land quality through phyto-remediation is needed. The study aimed to evaluate the ability of hyper-accumulator plants in remediating rice field contaminated by cadmium (Cd) and copper (Cu) in an effort to improve soil quality. The study was conducted in the screen house of the Indonesian Agricultural Environment Research Institute using a Randomized Block Design. Hyper-accumulator plants used were T1:, T2:, T3:, T4: spinach (), T5: mustard (), T6:, T7:, T8:, T9:, and T1:. The results showed that Cd and Cu contents in Vertisols of Sambung Macan, Sragen, Central Java were 1.18 and ppm, respectively. All hyper-accumulator plants could reduce Cd content in the soil after 2 months of planting (Duncan test level 5%). However, Cu content in the soil increased significantly (Duncan test level 5%). L. mucrunata adsorbed the highest Cu and significantly different compared with B. juncea. Cu content in 2-month old was higher than that of other plants, but the highest Cu content was found in stems and leaves of B. laevis. Cd content in roots of B. laevis was the highest and significantly different with other plants. Cd content in roots of R. corynbosa was also the highest, but not significantly different with that in other plants. [Keywords: Agricultural land, environmental pollution, heavy metals, phyto-remediation] INTRODUCTION The change of agricultural land for industrial areas has become the trigger of environmental pollution in agricultural areas. Environmental pollution will lower the quality and quantity of agricultural products. Heavy metal contamination in agricultural land is a major world s problem today. Heavy metal-specific issues in agricultural environment are mainly due to the accumulation of heavy metals in the food chains. The increasing amount of heavy metals would potentially contaminate soil and water. 1) Article in bahasa Indonesia has been published in Jurnal Tanah dan Iklim No. 3, 29, p The presence of heavy metals in agricultural environment would give negative impacts on all aspects of living beings. Heavy metal ions, such as arsenic (As), lead (Pb), cadmium (Cd), and mercury (Hg) are harmful to human health and the survival of life. Low concentrations of heavy metal ions could directly affect human health because they will be accumulating in the food chains. As other environmental pollutants, heavy metals can be transferred to the remote areas which then potentially disrupt the lives of biota and ultimately affect human health in a long period although they live time and away from the main pollution sources (Suhendrayatna 21). Kurnia (27, unpubl.) stated that agricultural environment pollution in some areas was occurred due to the industrial development. Rice fields in Rancaekek, Bandung, West Java, for example, produced low grain yield because the farmers used Cikijing river that had been contaminated by textile industry waste as irrigation water. The use of waste water for irrigating rice field land also occurred in Karanganyar Village, Sambung Macan District, Sragen, Central Java. In this area, farmers use waste water of textile industry continuously for irrigating rice field, especially in the dry season. The use of waste water continuously will lead to the accumulation of heavy metals in the soil which then could contaminate the rice grains produced. Subowo et al. (1999) reported that heavy metals reduced soil productivity and agricultural product quality. Agricultural land contaminants can be reduced by applying simple and inexpensive remediation techniques. One of the techniques to improve the quality of rice field contaminated by heavy metals is phyto-remediation, i.e. planting a crop that has an ability to transport a variety of pollutants or called as multiple uptake hyper-accumulator plant. Plants absorb ions from their environment through cell membranes. Some factors affected ion absorption by plants, namely (1) plant ability to accumulate ions until a certain concentration level, even greater than the level of ion concentration in the growing media and (2) differences of plants in nutrient needs. Plant root cells generally contain a higher ion concentration than the growing medium. Fitter (1982) reported that ion uptake by roots correlated with

2 18 N. Sutrisno Sa ad et al. ion concentration in the medium which corresponds with the rate of reaction catalyzed by enzyme in the substrate. This suggests that the presence of barriers in the cell membranes was only suitable for a specific ion. If ion concentration in the substrates was high, the barriers would be in the maximum rate until reaching the saturated uptake rate. According to Glass (1999) in Lasat (2), costs for improving heavy metal contaminated soils using hyperaccumulator plants were cheaper than other treatments as it cut costs up to tenfold (Table 1). Kurnia et al. (24) reported that F. globulosa reduced Cd and Cu contents in the soil from.13 to.11 ppm and from 58 ppm to 5 ppm, respectively. Mustard (B. juncea) absorbs 55% Cd and 98% Cu from the growing medium (Dushenkov et al in Mulyadi et al. 27). The study aimed to remediate rice field contaminated by Cd and Cu using plants that can absorb these ions (phyto-remediation) in efforts to rehabilitate and improve soil quality. MATERIALS AND METHODS Screen house experiment was conducted at the Indonesian Agricultural Environmental Research Institute in Pati, Central Java, in late July to September 27. Determination of hyper-accumulator plants used in this study was done by selecting plants that can survive in heavy metal contaminated soil. The selected plants represented weeds, plants that had economic value but could not be consumed, and plants that could be consumed. Selection of agricultural land contaminated by heavy metals was conducted based on the highest Cd and Cu contents among the soil samples used. Soil samples were taken from Karanganyar Village, Sambung Macan District, Sragen which was contaminated by textile industry waste water. Soil sampling referred to a method developed by Hadi (25). Soil analyses before treatment included soil physical and chemical characteristics as well as Cd and Cu contents measured using atomic absorption spectrophotometer (AAS). The results of soil analysis before treatment are presented in Table 2. The soil had silty clay, low organic C and N contents, very low total P, slightly acidic soil ph, and very high cation exchange capacity (CEC). Rice was planted in pots containing 7.5 kg of soil contaminated by Cd and Cu. Watering was given in accordance with plant conditions. The study arranged in Randomized Block Design with three replications. used were T1 =, T2 =, T3 =, T4 = spinach (), T5 = mustard (), T6 =, T7 = Table 1. Estimated costs of technology implementation for remediating heavy metal contaminated soils Treatment Cost (USD/t) Additional cost Vitrification Long-term monitoring Land filling 1-5 Transportation/soil digging/monitoring Chemical treatment 1-5 Contaminant treatment Electro-kinetic treatment 2-2 Monitoring Phyto-extraction 5-4 Monitoring Table 2. Characteristics of Vertisols of Sambung Macan, Sragen, Central Java before planted with hyper-accumulator plants Parameter Value Texture Sand (%) 17.8 Silt (%) Clay (%) ph 7.34 Organic-C (%) 1.24 Total-N (%).14 Total-P (mg/kg) 3.3 CEC (cmolc/kg) Cd (ppm) 1.18 Cu (ppm) 31.38, T8 =, T9 =, and T1 = Leperonia mucrunata. Duncan multiple range test was used to analyze the significant differences among treatments. RESULTS AND DISCUSSION Plant Growth Hyper-accumulator plant growth on Vertisols until the third month was shown in Figure 1. F. globulosa, C. plastytylis, B. laevis, spinach (), and mustard (B. juncea) grew normally because the environment was suitable to their ecosystem. S. poaeformis, E. dulcis, P. hydropiper, R. corynbosa, and L. mucrunata also grew normally, although the environment was not suitable to their requirement. Based on their performance, these plants could be used in phyto-remediation to improve soil quality by absorbing heavy metals from the soil. Cd and Cu Contents in Vertisols Contaminated by Waste Water Cd and Cu contents in the soils before treatment were 1.18 and ppm, respectively. Duncan test results in Table 3

3 Phyto-remediation for rehabilitation of agricultural land Plant height (cm) Month 1 Month 2 Month 3 Cd (ppm) Initial After 2 months Figure 1. Growth of hyper-accumulator plants in Vertisols of Sambung Macan, Sragen, Central Java Figure 2. Comparison of Cd concentrations in Vertisols of Sambung Macan, Sragen, Central Java before and after treated with hyper-accumulator plants Table 3. Effects of hyper-accumulator plants on Cd and Cu concentrations in Vertisols of Sambung Macan, Sragen, Central Java, during two months.9133a ab.9467a 37.6ab 1.167a 39.63ab.733a 36.13ab.99a 4.54a.8633a ab 1.733a ab.6467a 36.5ab 1.233a ab.5733a b CV (%) Cu concentration (ppm) Figure 3. Initial After 2 months Comparison of Cu concentrations in Vertisols of Sambung Macan, Sragen, Central Java before and after planting hyper-accumulator plants showed that the effect of hyper-accumulator plants on Vertisols varied. The effect was not different for Cd, while for Cu, it was significantly different. However, Cd content tended to decrease after the hyper-accumulator plants were planted for 2 months. L. mucrunata reduced the highest Cd content in the soil (Figure 2). In contrast, Cu content in the soil increased after 2 months (Figure 3). Increasing the Cu content allegedly occurred as a result of root exudates that release Cu bond in the soil. This result was consistent with that reported by Balingtan (28) that root exudates released Cu ions bounded in the soil so that increased the Cu content in the soil. Planting hyper-accumulator plants for a long period could absorb high Cu from contaminated soil. In other words, planting hyper-accumulator plants for 2 months would be uneffective. Three periods of planting were sufficient for the plants to absorb Cu from the soil so that the soil was safe for planting rice. The mobile characteristics of Cd also determined its absorption by hyper-accumulator plants. Alloway (1995) stated that factors controlling the accumulation of Cd and Cu in plants were concentration and type of ions in the soil solution, ion movement from soil to root surface, ion transport from roots to root surface, and ion translocation from roots to plant canopy. Cd is mobile in the soil so that the ion is easier absorbed by hyper-accumulator plants compared with Cu.

4 2 N. Sutrisno Sa ad et al. Cd and Cu Contents in Stems and Leaves of Hyper-Accumulator Plants Cd and Cu contents in stems and leaves at 2 months after planting varied (Table 4). Spinach () had the highest Cd content compared with other plants, showing that the plant absorbed highest Cd from soil and then stored in stems and leaves. This result was in accordance with that reported by Notohadiprawiro (26) that dicot plants (spinach) had higher potentials in absorbing heavy metals from soils compared with monocot plants. The high ability of spinach to absorb Cd from soil showed that the crop is a good hyper-accumulator so that it requires our attention in consuming this vegetable. Cu contents in stems and leaves were not significantly different. B. laevis absorbed higher Cu and stored it in stems and leaves as compared with other plants. High Cu accumulation in stems and leaves was among other caused by the physiological functions of leaves which need nutrients and metals simultaneously. Immobile properties of Cu also caused its high accumulation in stems and leaves. According to Suwondo et al. (25), chloroplast accumulated more than 5% Cu compared with other plant tissues. Agustina (24) in Suwondo et al. (25) also stated that Cu was needed by plants for metabolic processes, such as electron transfer in photosynthesis, cofactor of several enzymes, and chlorophyll formation. Cd and Cu Contents in Roots of Hyper-Accumulator Plants Table 5 showed that Cd and Cu contents in hyperaccumulator plant roots varied after 2 months of planting. B. laevis had the highest Cd content compared with other plants. This indicated that B. laevis absorbed more Cd from soil and stored it in roots. In contrast, R. corynbosa absorbed higher Cu compared with other plants. The following processes explain the role of roots in absorbing heavy metals from the soils. According to Salt et al. (1995) in Suresh and Ravishankar (24), a series of processes is in roots which involve pollutants from their environment are: 1. Phyto-accumulation (phyto-extraction), the process of accumulating contaminants from the growing media in roots. The process is also called hyper-accumulation. 2. Rhizo-filtration (rhizo-root), the process of adsorption or deposition of contaminant substances by roots to attach to the roots. 3. Phyto-stabilization, the attachment of certain contaminants in the roots that cannot be absorbed into the stem. These substances are closely attached (stable) on the roots so it will not be carried away by the flow of water in the media. Table 4. Cd and Cu contents leaf and branch of hyper-accumulator plants after two month treatment.15167d 64.84e.297c 97.11cd.1e 19.61a.455a 44.27e.36333bc 73.48ed.36933bc 122.8bc.1733d b.36867bc 129.3b.e b.41133ab 53.32e CV (%) Table 5. Cd and Cu contents in root of hyper-accumulator plants after two month treatment.8667ef 17.47ab.21667bcd 17.5ab.36a 7.52ab.24b 8.95ab.667f.57b.1333def 9.79ab.13667bcde 22.1ab.23bc 14.83ab.19667bcde 31.68a.11333cdef 9.83ab CV (%) Rhyzodegradation, also called enhanced rhyzosphere biodegradation or plented-assisted bioremediation degradation, i.e. the decomposition of contaminants by microbes around the roots. 5. Phyto-degradation (phyto-transformation), a process in which plants decompose contaminants that have complex molecule chains into harmless materials with more simple molecule structure that is useful for plant growth. This process is occurred in leaves, stems, roots or root areas and supported by enzymes released by the plant itself. Some plants release chemical enzyme to speed up the degradation process. Plants absorbed nutrients and metals from soil through their roots and then carrying it into the stems and leaves. In this study the heavy metal contents in stems and leaves were higher than that in the roots. This showed that for two months after planting, hyper-accumulator plants were able to optimally translocate the heavy metals from roots to stems and leaves.

5 Phyto-remediation for rehabilitation of agricultural land CONCLUSION Phyto-remediation plants showed a good performance in Cu and Cd contaminated Alfisols and served as a Cd absorber, but they unfunctioned well in absorbing Cu at two months after planting. Phyto-remediation plants grown on Vertisols contaminated by Cd decreased Cd content after two months, but Cu content increased. Cu contents in stems and leaves of spinach were the highest at 2 months after planting, and Cu contents in stems and leaves of B. laevis were the highest. Cd content in B. laevis roots was the highest and R. corynbosa roots showed the highest content of Cu. Phyto-remediation for 2 months improved rice field soil contaminated by Cd. Further study is needed regarding the appropriate time of Cd and Cu uptake by phyto-remediation plants and after three times of planting the phyto-remediation plants, rice is safe for consumption. REFERENCES Alloway, B.J Heavy Metals in Soils. Blackie and Son Ltd., London. Balingtan (Balai Penelitian Lingkungan Pertanian). 28. Fitoremediasi Lahan Pertanian Tercemar Limbah Industri dan Pertambangan. Laporan Akhir Penelitan TA 27. Balingtan, Jakenan, Pati. Fitter Fisiologi Lingkungan Tanaman. Gadjah Mada Univ. Press, Yogyakarta. Hadi, A. 25. Prinsip Pengelolaan Pengambilan Contoh Lingkungan. Gramedia Pustaka Utama, Jakarta. Lasat, M.M. 2. Phytoextraction of metals from contaminated soil: A review of plant/soil/metal interaction and assessment of pertinent agronomic issues. J. Hazar. Subst. Res. 2: Kurnia, U., H. Suganda, R. Saraswati, dan Nurjaya. 24. Teknologi pengendalian pencemaran lahan sawah. Dalam Tanah Sawah dan Teknologi Pengelolaannya. Pusat Penelitian dan Pengembangan Tanah dan Agroklimat, Bogor. Mulyadi, S.Y. Jatmiko, dan A.N. Ardiwinata. 27. Pencemaran Limbah Industri di Lahan Pertanian dan Teknologi Penanggulangannya. Dalam Pengelolaan Lingkungan Pertanian Menuju Mekanisme Pembangunan Bersih. Balai Penelitian Lingkungan Pertanian, Jakenan, Pati. Notohadiprawiro. 26. Logam Berat dalam Pertanian. Ilmu Tanah Universitas Gadjah Mada, Yogyakarta. Subowo, E. Tuberkih, A.M. Kurniawansyah, dan I. Nasution Identifikasi dan pencemaran kadmium (Cd) untuk padi gogo. hlm Prosiding Seminar Nasional Sumber Daya Lahan. Pusat Penelitian Tanah dan Agroklimat, Bogor. Suhendrayatna. 21. Bioremoval logam berat dengan menggunakan mikroorganisme: Suatu kajian kepustakaan. Seminar On- Air Bioteknologi untuk Indonesia Abad 21, 1-14 Februari 21. Suresh, B. and G.A. Ravishankar. 24. Phytoremediation - A novel and promising approach for environmental clean-up. Crit. Rev. Biotechnol. 24(2-3): Suwondo, Y. Fauziah, Syafrianti, dan S. Wariyanti. 25. Akumulasi logam cuprum (Cu) dan zincum (Zn) di perairan Sungai Siak dengan menggunakan bioakumulator eceng gondok (Eichhornia crassipes). Jurnal Biogenesis 1(2):