Volume 11, Number 1 (October 2023):4979-4984, doi:10.15243/jdmlm.2023.111.4979 ISSN: 2339-076X (p); 2502-2458 (e), www.jdmlm.ub.ac.id
Research Article
Utilization of post-tin mining land for porang (Amorphaphillus oncophyllus) cultivation by application of cow manure compost
Ismed Inonu1, Deni Pratama1*, Riko Irwanto2, Kurniahayati Utami Ningsih1
1 Departement of Agrotechnology, Universitas Bangka Belitung, Balunijuk, Merawang, Bangka, Bangka Belitung 33172, Indonesia
2 Departement of Biology, Universitas Bangka Belitung, Balunijuk, Merawang, Bangka, Bangka Belitung 33172, Indonesia
*corresponding author: [email protected]
Abstract Article history:
Received 13 November 2022 Revised 28 May 2023 Accepted 10 June 2023
Tailing post-tin mining land has a sandy textured and loose structure.
Those physical properties can affect the efficiency of fertilization and cause inefficiency of nutrient absorption in plants. That issue can be corrected by the application of organic material such as cow manure compost which has the potential for plant cultivation, especially for porang (Amorphaphillus oncophyllus Prain). This study aimed to examine the cultivation of porang plants in post-tin mining tailings by applying cow manure compost and to determine the best dose of cow manure compost for porang cultivation in artificial ex-tin mining land.
This study used a single-group randomized design method with the treatment factor being the dose of cow manure compost consisting of five dose levels (5 t ha-1, 10 t ha-1, 15 t ha-1, 20 t ha-1, and 25 t ha-1). Each treatment level was replicated with five replications, and each replication consisted of five populations so the total population was 125 plants. The results showed that the application of various doses of cow manure compost to artificial post-tin mining land affected the growth and yield of porang plants. The treatment of cow manure compost at a dose of 25 t ha-1 gave the best growth and yield of porang plants. Heavy metal (Pb) analysis on porang tubers showed that all doses of cow manure compost had a Pb content value of <0.059%, which means that cow manure compost can reduce heavy metal uptake in porang tubers.
Porang planted in artificial post-tin mining land is safe for consumption because lead (Pb) content was below the threshold of Indonesia National Standard (SNI) for food.
Keywords:
Amorphaphillus oncophyllus cow manure compost lead (Pb)
post-tin mining land tailing
To cite this article: Inonu, I., Pratama, D., Irwanto, R. and Ningsih, K.U. 2023. Utilization of post-tin mining land for porang (Amorphaphillus oncophyllus) cultivation by application of cow manure compost. Journal of Degraded and Mining Lands Management 11(1):4979-4984, doi:10.15243/jdmlm.2023.111.4979.
Introduction
Post-tin mining land is generally dominated by sand tailing that has a loose soil structure (Sukarman and Gani, 2017). This loose soil structure causes the domination of aeration pores in post-tin mining land (Sutono et al., 2020). The aeration pore can cause the land surface to experience water deficit or drought easily (Haryati et al., 2019). The condition of tailings
from post-tin mining land that has been left for 10 years has a fairly good population of soil organisms.
This factor can potentially be used as an indicator of soil fertility and revegetation in post-tin mining land (Asmarhansyah and Subardja, 2012). Moreover, with the addition of organic fertilizers such as compost, the soil fertility in post-tin mining land will improve further. One kind of compost that can be used for soil improvement in post-tin mining land is cow manure
compost. Cow manure compost is an organic material that can increase the physical, chemical and biological characteristics of the soil. Application of organic material in tailing post-tin mining land has the potential to reduce heavy metals such as lead and aluminum that are absorbed by cultivated plants (Inonu et al., 2020). Cow manure contains all of the essential nutrients needed by plants. Cow manure which is made into compost, has a low C/N ratio, which means that cow manure compost contains high nitrogen (Fadliani et al., 2019). Research from Fatoni et al. (2018) showed that the application of cow manure compost gave the highest average plant height and stem diameter compared to the use of other livestock manure compost treatments. Therefore, this study used cow manure compost as the main factor in the treatment for porang cultivation. Porang plants can be cultivated on planting media that contain organic material, with high organic content and well-aerated soil. The growth of these plants can grow optimally on dry and humus soil with a pH of 6-7 (Sari and Suhartati, 2015). In addition, porang can also grow well on light textured soils, for example, sandy loam soil, loose structure, and rich in nutrients (Siswanto and Karamina, 2016). Because of these conditions, porang plants also have the potential to be cultivated in post-tin mining land. In general, in agricultural land, the recommended dose of organic fertilizer to porang plants is 5 t ha-1, but in this research conducted in post- tin tailing sand, dose modifications were necessary to get the best growth and yield of porang.
Porang (Amorphaphillus oncophyllus Prain) belongs to the Araceae family, which is one of the tuber plants in Indonesia. Porang has had a high spotlight in Indonesia in recent years as an export commodity because that plant can produce glucomannan, which can thicken and form a gel. The presence of glucomannan makes porang plants not only as food but can be used to form gels, thickeners, stability, and good water absorbers (Faridah et al., 2012). This glucomannan has low in calories, so it can be useful as a healthy diet food (Sari and Suhartati, 2015). Porang cultivation is an effort to diversify food ingredients and provide industrial raw ingredients that can increase the value of export commodities in Indonesia. The demand for porang is very high from abroad countries, including Japan, China, Australia, and Vietnam. It caused the selling price at the farmer level to be quite high (Utami, 2021). However, this plant has a weakness, porang cannot be exposed to full sunlight directly or 100% light intensity because it can cause plant shoots to dry and plant growth to be stunted. Therefore, porang plants need shade (Rahmadaniarti, 2015).
Research about porang is necessary to do, especially the cultivation of porang plants on the tailings land of post-tin mining land by improving the limiting factor such as improving soil fertility by using cow manure compost and reducing the intensity of sunlight by providing artificial shade using paranet
60% cover. This study aimed to elucidate the effect of various doses of cow manure compost and 60% shade cover on growth, yield, glucomannan content, and metal absorption of porang in tailings of post-tin mining land.
Materials and Methods
The study used a single-group randomized design method. The treatment factor applied was the dose of cow manure compost, which consisted of five dose levels, namely K05 (5 t ha-1), K10 (10 t ha-1), K15 (15 t ha-1), K20 (20 t ha-1) and K25 (25 t ha-1).
Each level of treatment consisted of 5 replications.
Each replication consisted of 5 populations, so the total population was 125 plants. According to Novitasari and Caroline (2021), cow manure compost contains 1.53% N, 1.18% P, and 1.30% K.
The research was carried out by preparing the planting media that is tailing from post-tin mining land at Tanjung Gunung Village, Pangkalan Baru District, Central Bangka, with tailings aged about ten years after mining activities. However, for safety reasons, the research was not carried out in post-tin mining land at Tanjung Gunung Village, instead the artificial post- tin mining land was made in Experiment and Research Garden, Universitas Bangka Belitung, by using post- tin mining tailing from Tanjung Gunung Village. Post- tin mining artificial land was made by preparing 25 plots of agricultural land. A hole was made in each plot with a size of 200 cm x 100 cm x 60 cm. Tailing was filled in each hole by an amount of 1.2 m3 hole-1. Planting holes were made within the tailing with a diameter of 60 cm and a depth of 45 cm. Shade was applied by using a paranet with 60% light intensity.
Chemical analysis on tailing from post-tin mining land at Tanjung Gunung Village shows that nutrient content in tailing ranged from very low to low except for available phosphorus, which was very high and had average base saturation. Heavy metal content in this analysis was lead (Pb) which was within the normal limit (Table 1).
Porang was grown from bulbils that were obtained commercially. Porang planted from sprouted bulbil. Sprouted bulbils were sown in polybags (10 x 15 cm). Porang seedlings were ready to move to experiment land after the age of 60 DAS (days after seedling). The application of cow manure compost was done by digging a hole in the tailing. Each plot was dug with five planting holes. Furthermore, the hole was added cow manure compost according to five treatments of dose levels, and porang seedlings were planted after cow manure compost application was done. Cultivation of porang plants included watering, replanting, weeding, and fertilizing. The transplantation of dead plants was carried out maximum at the age of 4 weeks after planting.
Weeding was done mechanically on beds that had been overgrown with weeds. Inorganic fertilizers application was made at 45 DAP (days after planting)
with a mixture of Urea 0.36 g plant-1, SP-36 0.36 g plant-1, and KCl 0.72 g plant-1. Fertilizer was applied by burying it in a circular pattern around the main plant. Harvesting of porang plants was done when porang reached age 8 MAP (months after planting).
The harvesting process was done by gently removing all parts of the plant (roots, tubers, stems, and leaves) using a small hoe so that the tubers remained intact and could be removed from the soil.
Table 1. Chemical characteristics of post-tin mining tailing from Tanjung Gunung Village, Pangkalan Baru District, Central Bangka.
Soil Chemical Properties
Value Criteria
Organic C (%) 0.37 Very low
Total N (%) 0.05 Very low
C/N Ratio 7.00 Low
Available P (mg kg-1) 43.21 Very High Potential P
(mg 100 kg-1) 18.30 Low
Potential K (mg 100
kg-1) 8.13 Very low
Cation Exchange
Capacity (cmol(+) kg-1) 1.24 Very low Base-Saturation (%) 54.03 Average Exchangeable-Al
(cmol(+) kg-1) 0.46 Very low Exchangeable-H
(cmol(+) kg-1) 0.04 Very low Exchangeable-K
(cmol(+) kg-1) 11.00 Very low Exchangeable-Na
(cmol(+) kg-1) 0.06 Very low Exchangeable-Ca
(cmol(+) kg-1) 0.39 Very low Exchangeable-Mg
(cmol(+) kg-1) 0.11 Very low Lead (Pb) (ppm) 52.36 Normal Limit Note: Determination of soil and heavy metal criteria based on the Soil Research Center (Balittan, 2009).
The growth variables of porang were observed, consisting of an increase in plant height, an increase in the number of leaves, an increase in stem diameter, and an increase in leaf diameter. The yield variables of porang were bulbil weight, tuber diameter, tuber
weight, and glucomannan content. Heavy metal (Pb) content was also observed to determine the absorption of heavy metal content in porang tuber when cultivated in post-tin mining land. Glucomannan content was analyzed using research methods from Hadi and Kurniawan (2020). Porang samples were analyzed in the Laboratory of the Faculty of Agriculture, Fisheries and Biology, Universitas Bangka Belitung. Heavy metal (Pb) analysis in porang tubers was carried out in the Laboratory of the Central Agro Industry Center, Bogor, West Java. Data obtained were analyzed using the ANOVA test at a 95% significance level, followed by Duncan’s Multiple Range Test (DMRT) at a 95% significance level.
Results and Discussion
The observed growth variables showed that the application of cow manure compost had a significant effect on all variables of plant growth (increase in plant height, increase in the number of leaves, increase in stem diameter, and increase in leaf diameter). Plant yield variables that were observed had no significant effect on tuber diameter, tuber weight, and glucomannan content but had a significant effect on the bulbil weight variable (Table 2). The application of several doses of cow manure compost on porang showed that an increase in plant height at a dose of 5 t ha-1 had the smallest result and was significantly different from other doses, while the dose of 25 t ha-1 had the highest result but not significantly different with a dose of 10 t ha-1, 15 t ha-1 and 20 t ha-1. A dose of 25 t ha-1 had the highest result in an increase in the number of leaves and was significantly different with a dose of 5 t ha-1 and a dose of 10 t ha-1, but was not significantly different from other doses. An increase in stem diameter at the dose of 10 t ha-1 had the highest diameter and was significantly different at doses of 5 t ha-1 and 25 t ha-1 but not significantly different from other doses. The increase in leaf diameter at a dose of 25 t ha-1 was the highest and significantly different from all other doses (Table 3). Improving tailing conditions with cow manure compost significantly affects the growth variables of porang plants, such as increasing plant height, number of leaves, stem diameter, and leaf diameter (Tables 2 and 3).
Table 2. Effects of various doses of cow manure compost on growth and yield of porang plants on tailings.
Parameters F Value Pr>F CV (%)
Increase in Plant Height (cm) 4.22 0.0069* 11.74
Increase in Number of Leaves (pieces) 2.84 0.0359* 6.26
Increase in Stem Diameter (mm) 4.27 0.0076* 5.96
Increase in Leaf Diameter (cm) 8.97 0.0001* 7.88
Bulbil Weight (g) 6.78 0.0006* 24.12
Bulbil Diameter (mm) 0.62 0.7522ns 24.13
Tubers Weight (g) 1.17 0.3729ns 7.25
Glucomanan content (%) 1.42 0.2605ns 5.65
Note: Pr > F = probability value, * = significant effect, ns = not significant, CV = coefficient of variance.
Table 3. Application of various doses of cow manure compost on growth variables of porang.
Compost Dose (t ha-1)
Parameters Increase in Plant
Height (cm)
Increase in Number of Leaves (pieces)
Increase in Stem Diameter
(mm)
Increase in Leaf Diameter (cm)
5 29.90 b 1.28 c 9.71 b 25.71 c
10 36.55 a 2.24 bc 18.06 a 27.45 c
15 38.03 a 2.60 abc 14.16 ab 31.61 b
20 36.40 a 3.16 ab 16.02 ab 32.93 b
25 41.05 a 4.00 a 10.79 b 36.45 a
Note: The number followed by the same letter in the same column showed no significant difference in DMRT test at 95%
significant level.
Based on soil analysis results, most of the soil chemical properties in tailing from Tanjung Gunung Village have very low to low nutrient content (Table 1). Hamid et al. (2017) reported the low content of total N, organic C, and potential P in post-tin mining land occurs due to the loss of organic material caused by peeling off the topsoil from mining activities.
Furthermore, tailing post-tin mining land that is dominated by sand fraction has high permeability and low water resistance (Pratiwi et al., 2012). Cow manure compost as an organic material can increase soil chemical, physical and biological characteristics (Hartatik et al., 2015). According to Wasis and Sandrasari (2011), higher organic material content makes higher cation exchange capacity and has an important function in the enzyme system needed in the synthesis of chlorophyll.
Based on those statements, cow manure compost has the ability to increase the physical, chemical, and biological quality of tailing post-tin mining land and significantly improve the growth of porang plants.
Cow manure compost as organic materials can improve soil structure in post-tin mining land.
Improved soil structure greatly affects plant growth and influences microbial activities. Organic material can also increase the soil ability to hold water. Plants that have good water content will not experience a decrease in the photosynthesis process due to drought stress (Nurtjahya et al., 2020). Water acts as a solvent and place where all biochemical reactions occur or
provides the energy needed in the photosynthesis process. Organic material also holds and maintains cations in the soil and increases the cation exchange capacity (Sukma, 2015).
The yield variable of porang plant, especially the bulbil weight variable, was the heaviest at the dose of 25 t ha-1 and significantly different from other doses.
The tuber diameter and weight variables showed no significant difference from each treatment. The glucomannan content variable also did not give a significant effect from each treatment, but glucomannan content tended to increase and had the highest content at a dose of 25 t ha-1 (Table 4). Porang yield can be seen from bulbil weight, tuber diameter, tuber weight, and glucomannan content in porang tubers. Porang plants can produce stem tubers because the leaves tend to grow healthy. According to Sari et al. (2019), a high number of healthy leaves will accelerate the rate of photosynthesis and produce more photosynthesis. This statement was supported by Susanto et al. (2014), who stated that higher photosynthate produced by plants would make the higher total dry weight of plant yields obtained. The quality of porang plants on glucomannan content shows that the highest level of glucomannan, which is 50%, was produced by the highest treatment of cow manure compost (25 t ha-1). This result was similar to research from Handayani et al. (2020), which stated that the test for glucomannan content from porang in Ngayun Sub-district obtained was 50.103%.
Table 4. The effect of various doses of cow manure compost on yield and glucomannan content of porang.
Compost Dose (t ha-1)
Parameters Bulbil Weight (g) Tubers Diameter
(mm)
Tubers Weight (g)
Glucomannan content (%)
5 6.96 bc 80.88 245.14 39.99
10 4.47 c 75.13 178.31 43.33
15 7.06 bc 75.41 196.19 43.33
20 9.20 b 67.82 195.13 46.67
25 12.36 a 72.88 204.16 50.00
Note: The number followed by the same letter in the same column shows no significant difference in the DMRT test at the 95%
significant level.
The requirement for glucomannan content that has been determined by Indonesian Standard (SNI) No.
7939 is 15-<20 for class III, 20-<35% for class II and
≥35% for class I (BSN 2020), so that the glucomannan content in this research sample meets the requirements and has potential to be included into class I.
Based on data research and statements, porang has the potential to grow in tailing post-tin mining land as long as the quality of tailing is improved, one of them by improving the land quality by application of cow manure compost. Heavy metal (Pb) analysis on tailings post-tin mining land from Tanjung Gunung Village shows that tailing has 52.36 ppm of Pb (Table 1). Based on laboratory analysis of lead (Pb) content, porang tubers cultivated in tailings post-tin mining land from Tanjung Gunung Village that applied cow manure compost had a Pb content value of <0.059%, far below lead (Pb) content in tailing. It means that porang cultivated in tailing with the application of cow manure compost as organic material absorbs less lead (Pb). According to Indonesia’s standard (SNI) No.
7387, the maximum level of Pb in food is 0.5 mg kg-1 (BSN, 2009). This shows that the value of Pb levels is still below the threshold standard and safe for consumption.
Organic material can decrease metal absorption potential by plant tissue (Gul et al., 2015) and bind heavy metals, reducing bioavailability (Anggriawan, 2022). Organic material provides cations (positive ions) that can be exchanged with Pb metal cations (Hermana and Nurhayati, 2010). Organic material also contained lignin, amino acids, and carbohydrates that reacted in the soil through the humification process and formed humic compounds. Humic compounds reduce metal content in soil by binding excess free metal in soil by metal chelation process (Tan, 2011), cation exchange, and electrostatic bonding (Prasetiyono, 2013), then reducing metal absorption in porang tubers cultivated in post-tin mining land.
Conclusions
The application of different doses of cow manure compost in tailing post-tin mining land significantly affected every porang growth parameter and porang yield on the bulbil weight variable. Cow manure compost also reduced the lead (Pb) uptake in porang tuber cultivated in tailing post-tin mining land. The application of cow manure compost in post-tin mining tailings at a dose of 25 t ha-1 provided the best growth and yield of porang plants.
Acknowledgments
The authors are very grateful to Universitas Bangka Belitung for funding this research through Faculty Lecturer Research Program by The Institution of Research and Community Service (LPPM).
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