Biogas and bioslurry utilization on dairy-horticulture integrated farming system in Tutur Nongkojajar, District of Pasuruan, East Java, Indonesia

R E M F Osak, B Hartono¹, Z Fanani¹ and H D Utami¹

Faculty of Animal Husbandry, University of Sam Ratulangi, Indonesia
richard_osak@yahoo.com
¹ Faculty of Animal Husbandry, University of Brawijaya, Indonesia

Abstract

Poverty, population growth, environmentally friendly agriculture and environmental degradation are increasingly being considered as focal points for research and development. In order to develop environmentally friendly farming in complex mixed cropping-livestock systems at the village level, the goal of this study is to economic study for biogas and bioslurry utilization on production of dairy and horticulture integrated farming system (IFS) system in Tutur Nongkojajar, Indonesia.

The research result are (1) The largest contribution subsystem in dairy-horticultural farming system revenue is dairy cattle farming about 46.54%, while contibution both of  biogas and bioslurry are 2.17 and 3.46 percent. Contribution of  biogas is still a bit, because the habits of households using biogas is still unfamiliar or still not accustomed than using kerosene or LPG (liquid petroleum gas) fuel. In the other aspects, forage farm revenue greater than horticulture farm revenue, because most farmer’s land is planted forage for support the main farming activities of dairy farming; (2) Total forage fodder (HMT) and horticulture plant waste feed provides significant contribution to the dairy farming revenue (PDSP); (3) Used biogas production value (PBG) is influenced significantly by the need  (demand) for gas per household (KBTG). Gas usage per household (KBTG) significantly influenced by the need (demand) for gas per household (KBTG) and cost of used LPG (LPG); and 4) Organic fertilizer revenue (PPO) significantly influenced by the ability of capital (MDL) and processing cost of organic fertilizer (BPO), the smaller the ability of capital then farmers will increase utilize organic fertilizer. And organic fertilizer needs (KBTPO) significantly influenced by horticultural crop revenue (PTH).

Key words: environment, global warming, methane, sustainable agriculture

Introduction

Environmentally friendly development have become issues of concern to the entire world now. The most critical environmental problems today is global warming. Global warming is warming of the earth's atmosphere, due to accumulation principally of carbon dioxide and methane. Conventional agriculture is known to cause environmental harm, such as soil and pasture degradation because it involves intensive tillage, in particular if practised in areas of marginal productivity. Meanwhile, diversified systems according to FAO (2001) consist of components such as crops and livestock that coexist independently from each other.

Environmentally sound livestock development, it should be done through an integrated and sustainable farming systems in order to reduce the effects of the environmental impact caused by livestock, especially ruminants livestock. In this case, integrating crops and livestock serves primarily to minimize risk and not to recycle resources. In an integrated system, crops and livestock interact to create a synergy, with recycling allowing the maximum use of available resources. Crop residues can be used for animal feed, while livestock and livestock by-product production and processing can enhance agricultural productivity by intensifying nutrients that improve soil fertility, reducing the use of chemical fertilizers.

Explained that fossil-fuel based industrial development is the major cause of the environmental imbalance; however according to Preston and Leng (1989), agricultural practices are major factors with the capacity of adding to greenhouse gases (GHG)  as the consequence of most modern production technologies or reducing them by environmentally friendly development schemes.

One of several way reducing greenhouse gases by environmentally friendly development schemes is integrated farming system especially integration of livestock and plantation or crop. Devendra (2011) explained that it is important to keep in perspective the terms integration and integrated systems. Integration involves various components, namely crops, animals, land and water. Integrated systems refer to approaches that link the components to economic, social and ecological perspectives. The integration of livestock with trees, food crops and aquaculture is seen as the most appropriate technology to use the natural resources in a system that is productive and sustainable (Preston, 2000).

In recent decades, there have been practical innovations in integrated production systems based on conservation agriculture that harness synergies between the production sectors of crops, livestock and agroforestry that ensure economic and ecological sustainability while providing ecosystem services. FAO’s Agriculture and Consumer Protection Department confirmed the importance of the role of integrated crop livestock systems for sustainable development, and that integrated crop-livestock systems, implying a diverse range of integrated ecological, biophysical, socio economic conditions, have been a foundation of agriculture for hundreds of years (FAO, 2010).

The future need to promote the integrated crop and livestock systems pattern. IFAD (2009) said that technologies and management schemes that can enhance productivity need to be developed, at the same time, ways need to be found to preserve the natural resource base. Within this framework, an integrated crop-livestock farming system represents a key solution for enhancing livestock production and safeguarding the environment through prudent and efficient resource use.

One alternative approach to diversify agricultural production is to integrate cash grain cropping with ruminant livestock production. Agriculture including crop production and livestock provides for the food, fodder, and fuel needs in rural regions of many countries. Randall (2003) cited four positive factors associated with livestock being integrated into cropping enterprises: (i) crops produced on the farm can be used to feed the livestock, thus minimizing the importing of outside feed stuffs in livestock production; (ii) livestock manure can serve as the primary source of nutrients for crop production, thereby cycling nutrients from the crops through the animals and back out onto the land; (iii) livestock can serve as the sink for agricultural byproducts; and (iv) ruminant livestock encourage the establishment of perennial grass and legume forages as a primary feedstuff.

Agricultural production systems have become increasingly specialized. The lack of diversification has had negative economic, biological, and environmental consequences according to Sulc andTracy (2007). The possibility of producing food, fodder and biomass fuel in an integrated farming system (IFS) therefore be examined, particularly in developing countries, which are so heavily dependent on agriculture (Ralevic et al, 2012).

Preston and Leng (1989) explained that in a system the processing of the livestock manure by anaerobic digestion is a key component as it has many positive features such as reduction in emission of methane (a major actor in global warming), decrease in pathogens (better health of people and animals), production of  biogas for cooking (reduced pressure on forests for fuel wood; more comfortable working conditions in the kitchen for women) and improved nutrient recycling (reduced need for chemical fertilizer). There are six main parts to the anaerobic digester: Inlet (mixing tank) where animal dung is inserted to feed the digester, reactor (anaerobic/non-oxygenated digester chamber), gas storage (storage dome), outlet (divider chamber), gas carrier system and the bio-slurry pit or the animal dung compost pit which has been reduced of any gas (deducted of all gases). A combined mixture of feces and water (which takes place  in the inlet or the mixing tank) flows through the pipeline towards the digester. The mixture produces gas, through a process of digestion which takes place in the reactor, and is then stored in the gas storage chamber (upper side of the dome). San Thy et al (2003) reported that the major determinant of rate of gas production was the loading rate expressed as kg of manure solids per m³ of liquid digester volume.

The slurry flows out from the digester towards the outlet and results in what we know as bio-slurry that passes through the overflow outlet and is flowed into the slurry pit. Bio-slurry discharged from the reactor retains all nutrients originally present in the feeding material which makes bio-slurry a potent organic fertilizer. Proper application has been proven to provide higher yields than regular manure. It also provides a viable solution to nutrient depletion of many agricultural soils in developing countries. The nutritional value of the slurry can greatly be improved if urine can also be collected in the digester. The use of bio-slurry thus considerably boosts agri- and horticultural production and will improve productivity of fish rearing. Sophin and Preston (2001) explained that the main products from the biodigester are biogas and effluent, and the latter has considerable potential as fertilizer because the anaerobic digestion process results in conversion of organic nitrogen in the manure to ionized ammonia which can be used directly by plant roots.

Many people in rural areas in Indonesia have limited access to energy sources that are economical and convenient to use. The biogas or processed cow manure also provides opportunities for rural communities to reduce expenses and gain a better income.

Biru (2014) reported that The Biru Programme started in May 2009 and is targeting the construction of 11,000 domestic biogas digester units in eight provinces in Indonesia. Until the end of 2013, biogas digester built has reached more than 11,000 units, where numbers of digesters produced around 2009-2013 which resulted in 11,249 digesters include in Tutur Nongkojajar District of Pasuruan, East Java.

Current dairy farming in Tutur Nongkojajar is not only to produce fresh milk as primary product, but also able to produce by-products such as organic fertilizer and biogas alternative energy. It seems that the current dairy farming in that site is currently being integrated with horticultural crops in the integrated farming system pattern, so the cycle of dairy cattle farming activities in addition to increasing household income also preserve a sustainable environment.

Poverty, population growth, agricultural environmentally friendly and environmental degradation are increasingly being considered as focal points for research and development. In order to develop environmentally friendly farming in complex mixed cropping-livestock systems at the village level, the goal of this study is to economic study for biogas and bioslurry utilization on production of dairy and horticulture integrated farming system (IFS). IFS implementation in particular the utilization of biogas and bioslurry could have economically advantageous or not to the farming household economy, for that reason the study was conducted.

Materials and Methods

Location

The research was conducted in District of Pasuruan, Province of East Java, Indonesia. In this district has one of sub district that had the largest  population of dairy cattle is Sub District of Tutur Nongkojajar. Selection of the overall study site using multistage sampling method, but every level of research conducted in the area by the purposive sampling. This study used research unit are dairy farmers who are members of  Dairy Farmers Cooperative (KPSP) ˈSetia Kawanˈ Nongkojajar as the main research unit.

Data collection

The research was conducted using a survey, where the method of sampling was purposive sampling. Lagares and Albandoz (2001) explained that purposive sampling is selecting the sample, depending on research purpose. Main criterias of sample respondent according to the research purpose are a farmer have dairy cow, horticultural crops, forage plants, and has a biogas reactor installation. Determination of the number of samples that> 10% of the total population. Total population of dairy farmer in Sub District of Tutur Nongkojajar who have had a biogas reactor installation are 1,220 farmers, so that the number of samples at least 122 farmers. The number of sample villages are 6 villages, so that each village consists of 20-21 respondent farmers sample.

Variables and Statistical analyses

Main research variables are presented as follows:

• Dairy farming income (PdSP) is amount of dairy farming net revenue derived from the sale of milk and dairy value reduced all costs of production in dairy farming (IDR/year)

  
  

• Horticultural crops farming income (PdT) is amount of horticulture farming net revenue derived from the sale value of vegetables, fruits and flowers productions are used either alone or sold reduced by all crop production costs (IDR/year).

  
  

• IDR Biogas production income (PBO) is the amount of the value of the biogas produced and used equaluivalent to LPG price reduced by biogas production costs (IDR/year).

  
  

• Organic fertilizer income (PPO) is the amount of the sale value of organic fertilizers used in horticultural farming and forage crops, whether self used or sale reduced by the cost of organic fertilizer production process (IDR/year).

Analysis of the data is arranged in linear equations through the simultaneous equations which are identified with the easiest technique is Indirect Least Squares (ILS), using simultaneous equations over the identification of the used methods Two Stage Least Square (2SLS). The data were subjected to analysis of variance (ANOVA) and data processing is performed by the Statistical System (SAS) computer program according to SAS (2011).

The specifications of the endogenous variables are presented as follows:

1)      Dairy farm revenues (PdSP) is influenced by the amount of lactation cow (JSL), Total labor in dairy farm (TkPS), Total consumed forage (HMT), Total consumed concentrate (Kst), Milk Price (HS), Quality of milk (KwS), Costs of medicines, chemistries and animal health (OVK), and the value of horticulture waste that consumed by dairy cow (LBT). The model was:

Note :

• c_1.1, c_1.2, c_1.3, c_1.4 , c_1.5, c_1.6, c_1.7, and c_1.8   are parameter coefficients of each exogen variable in dairy farm revenues equation model

• c_3.0 is a constant coefficient in dairy farm revenues equation model, and

•  µ_13.i is due to model measurement errors in dairy farm revenues equation model.

2)      Biogas production income (PBg) is influenced by the amount of man-days labor (TK) in the production process of biogas, amount of capital (MDL), amount of dairy manure production (FCS), amount of gas need (Kbt), and the price of liquefied petroleum gas (LPG). The model was:

Note:

• c_2.1, c_2.2, c_2.3, and c_2.4 are parameter coefficients of each exogen variable in biogas production income equation model

•  c_2.0 is a constant coefficient (intercept) in biogas production income equation model

•  µ_12.i is due to model measurement errors in biogas production income equation model.

3)      Organic fertilizer income (PPO) is influenced by the amount of man-days labor (TK) in the process of production of organic fertilizer, the amount of capital (MDL), the amount of dairy manure production (FCS), the amount of fertilizer needs (Kbt), the amount of slurry production (Slr), the price of organic fertilizer (HPO) and the price of chemical fertilizers (HPK). The model was:

Note:

• c_3.1, c_3.2, c_3.3, and c_3.4 are parameter coefficients of each exogen variable in organic fertilizer income equation model

• c_3.0 is a constant coefficient (intercept) in organic fertilizer income equation model

• µ_13.i is due to model measurement errors in organic fertilizer income equation model

Results and discussion

Indonesia are currently has a biogas and bioslurry development program, the Indonesia domestic biogas programme as an initiative of Hivos and SNV. Closely working with the Indonesian Ministry of Energy and Mineral Resources, the programme is implemented by Yayasan Rumah Energi (YRE) with funds made available by EnDev (Energising Development), the Norwegian Embassy and partners in promoting access to a modern and sustainable form of renewable energy for rural people.

The Indonesian Domestic Biogas Programme (IDBP) is in Indonesia better known as the BIRU programme; an acronym of Biogas Rumah, or ‘biogas for the home’. BIRU aims to promote the use of biodigesters as a local, sustainable, energy source by developing the market while working towards the development of a commercial, market-oriented sector, leading to the creation of jobs. Started in May 2009 with financial support from the Netherlands Embassy and as of December 2013, has built 11,249 biogas digesters in nine provinces in Indonesia covering 568 sub districts in 103 districts (Biru, 2013).

District of Pasuruan is one of districts that choosed for implementation the programme due to  as one of the largest milk producing areas in East Java, Indonesia. This district has a sub-district as a center for dairy farming that is Tutur Nongkojajar. Dairy cow population in this sub district is amount 17.765 head, with milk production about 63,000 liters per day or 23,523.5 tonnes a year, and with potential production of dairy cattle dung about 20 kg per cow per day have been used biogas through household-scale biogas reactor (Biru, 2012).

Reactor technology used in research site is the fixed-dome reactor. The biogas digesters/ reactors is an Biru’s adaptation of existing systems used in other countries and function as converters of dairy cattle dung, and possibly human excrement and other organic materials, into combustible biogas. Uses of biogas consumption in households, among othersare to fuel simple gas stoves for cooking and pump lamps for lighting. This fixed-dome reactor is made from masonry and concrete work concealed underground.

The fixed dome biogas plant has a minimum lifetime of 15 years if properly used and maintained. Maintenance is easy, it merely requires the occasional checking and – if necessary – repair of pipes and fittings. To operate one unit, the farmer needs to have at least 2 cows or 7 pigs (or a flock of 170 poultry) to produce enough feed for the reactor to be able to generate sufficient gas to meet their daily basic cooking and lighting needs. The system is proven  to be environmentally friendly and a clean energy source according to Pranadji (2010) and Biru (2014).

Profile of dairy farming in Nongkojajar, generally as small scale farmers, traditional dairy farming, kept in the yard of the house with a simple system of housing and equipment. The farmers generally have relatively small field land, cultivated fruits, horticulture crops and forage crops fodder. Crop-livestock integrated farming system (CLS-IFS) or integration system of dairy and plants generally have not been applied, despite the research studies that recommend this integration system. Currently practice in sub district of Tutur Nongkojajar, where the dairy cattle with plants farming only as a mixed pattern farming that almost like CLS-IFS as showed in Figure 1. Figure 1 showed the flow diagram of dairy-horticulture integrated farming system pattern, which dairy cow produce by-products such as manure, then manure processed into biogas and bioslurry which ultimately contributes indirectly to the farming revenue.

Figure 1: Flow Diagram of Dairy-Horticulture Integrated Farming System Pattern in Sub District of Tutur Nongkojajar, East Java, Indonesia

Table 1 showed that the contibution of  biogas and bioslurry in farming revenue are 2.17 and 3.46 percent. Contribution of biogas is still a bit in farming revenue, because the habits of households using biogas is still unfamiliar or still not accustomed than using firewoods,  kerosene or LPG (liquid petroleum gas) fuel. Pranadji et al (2010) reported that 72,5% of household had a fairly good perception of LPG fuel than others fuel. To excite or motivate households to use biogas and bioslurry that they produce, then the government should subsidize or provide incentive policy for the use of biogas and bioslurry.

The results showed that the issued capital by 122 farmers ranged from IDR16 million to IDR149 million with an average of IDR45,049,180. For a number of lactating cows ranged from 1 to 15 heads with an average of 4 heads each farmer. The amount of revenue used dairy cattle ranged from IDR30,420.83 to IDR107,515,336.11, with an average of every farmer is IDR23,357,321.17.  These results indicated that, dairy farming provided enough income for the farmer household, moreover when calculated and analyzed with the utilization of biogas and bioslurry.

Figure 2: Contribution of each subsystem/component on Dairy-Horticulture Integrated Farming System (IFS) Pattern Revenue

Figure 2 indicated that the highest revenue in dairy-horticulture integrated farming system is dairy cattle farming about 46.54%, while the smallest is utilized biogas sale value about 2.17%. In the other aspects, forage farm revenue greater than horticulture farm revenue, because most farmer’s land is planted forage for support the main farming activities of dairy farming. Only small part of farmer’s land was used for horticultural plants like vegetables, fruits tree or flower plants.

Table 2 showed that average biogas production each dairy farmer household about 620.41 m³ per year equivalent to 285.39 kg liquid petroleum gas (LPG) fuel. This is indicated that the utilization of biogas save the use of LPG, reduce the destruction of forests and environmental impact as a result of cow dung and firewood utilization. In other hand, government througt PT Pertamina (State Oil and Natural Gas Mining Company) selling LPG with price of IDR5,850 , by used of biogas amount 100,80 kg per year can save a subsidy about IDR453per kg can save a subsidy about IDR453,588-503,987 or average IDR470,387 per year. Moreover, LPG economic price in Indonesia about IDR8,500-9,000/kg, by used of biogas amount 100,80 kg per year per farmer household, the government can save IDR589,664 per year per farmer household.  

Bioslurry (fresh and compost) production about 17,371.48 kg per year each farmer household as subtituted of chemical fertilizers that used in forage and horticulture plants. Utilized bioslurry sale value about IDR8,685,737.70 per year pe household can give profit to farmer about IDR1,737,147.54 per year pe household. This seemly just a bit contribution, but have environmenly and healthy advantages for to improve the balance of soil nutrients and reduce chemistry fertilizer utilization which adversely affects the health of food consumers.

The first statistically model for the study, dairy farm revenues (PdSP) is influenced by theunt of lactation cow (JSL), total labor in dairy farm (TkPS), total consumed forage (HMT), total consumed concentrate (Kst), milk price (HS), quality of milk (KwS), costs of medicines, chemistries and animal health (OVK), and the value of horticulture waste that consumed by dairy cow (LBT). Results of statistical analysis can be seen in Table 3.

According to estimated parameters in Table 3, Dairy Farming Income (PDSP) equation model model is :

Table 3 showed that in dairy farming income (PDSP) equation, among eight exogenous variables there are six variables that partially or simultaneously influences to dairy farming income (PDSP). There are lactation cows number (JSl), labor number in dairy farming (TKPS), forage fodder amount (HMT), milk price (HS), cost of AI, medicines, vaccine & chemistry (OVK), and the value of plants waste (LbT) as showed in Figure 3.

Figure 3: Diagram of Dairy Farming Income (PDSP) Model

The secound statistically model for the study, biogas production income (PBg) is influenced by the amount of man-days labor (TkBg) in the production process of biogas, amount of capital (MDL), amount of dairy manure production (FCS), amount of gas need (KbtG), and the price of liquefied petroleum gas (LPG). Results of statistical analysis can be seen in Table 4.

According to estimated parameters in Table 4, the value of biogas production used (PBG) equation model model is :

Therefore, based on Table 4 indicated that cost of using liquid petroleum gas (LPG) provided negatively affects to the value of biogas production used (PBG), because the greater the household expenditures for the purchase LPG will reduce the use of biogas. Partially there are three variables provided the positive effect to used for biogas production value (PBG): the amount of man-days labor in the production process of biogas (TkBg), amount of capital (MDL), amount of gas need (KbtG), and the price of liquefied petroleum gas (LPG) as showed in Figure 4.

Figure 4: Diagram of biogas production income (PBg) model

The third statistically model for the study, used organic fertilizer income (PPO) is influenced by the amount of man-days labor (TkPO) in the process of production of organic fertilizer, the amount of capital (MDL), the amount of dairy manure production (FCS), the amount of fertilizer needs (KbtPO), the amount of slurry production (Slr), the price of organic fertilizer (HPO) and the price of chemical fertilizers (HPK).  Results of statistical analysis can be seen in Table 5.

According to estimated parameters in Table 5, the used organic fertilizer income (PPO) equation model model is:

The analysis indicated that in revenue organic fertilizer (PPO) equation model, partially there are four variables: capital (MDL), amount of dairy dung (Fcs), total labor for organic fertilizer (TkPO), and cost of organic fertilizer process (BPO) has positive effects to organic fertilizer revenue (PPO) as showed in Figure 5.

Figure 5: Diagram of used organic fertilizer income (PPO) model

Conclusions

• The largest contribution subsystem in dairy-horticultural farming system revenue is dairy cattle farming about 46.54%, while contibution both of  biogas and bioslurry are 2.17 and 3.46 percent. Contribution of  biogas is still a bit, because the habits of households using biogas is still unfamiliar or still not accustomed than using kerosene or LPG (liquid petroleum gas) fuel. In the other aspects, forage farm revenue greater than horticulture farm revenue, because most farmer’s land is planted forage for support the main farming activities of dairy farming.

  
  

• Average biogas production each dairy farmer household about 620.41 m³ per year equivalent to 285.39 kg liquid petroleum gas (LPG). And by used of biogas amount 100,80 kg per year per farmer household, the government can save IDR589,664 per year each farmer household. To excite or motivate farmer households to use biogas and bioslurry that they produce, then the government should subsidize or provide incentive policy for the use of biogas and organic fertilizer.

  
  

• Total forage fodder (HMT) and horticulture plant waste feed provides significant contribution to the dairy farming revenue (PdSP).

  
  

• Used biogas production value (PBG) is influenced significantly by the need  (demand) for gas per household (KBTG). Gas usage per household (KBTG) significantly influenced by the need (demand) for gas per household (KBTG) and cost of used liquid petroleum gas (LPG).

  
  

• Organic fertilizer revenue (PPO) significantly influenced by the ability of capital (MDL) and organic fertilizer processing cost (BPO), the smaller the ability of capital then farmers will increase utilize organic fertilizer. And organic fertilizer needs (KbtPO) significantly influenced by horticultural crop revenue (PTH).

Suggestions

• Research is needed to generate knowledge and innovative practices to underpin farmer adoption and scaling of promising crop-livestock systems for sustainable production intensification.

  
  

• Political will, and policy and institutional support for the adoption and enabling the spread of innovations and practices associated with promising crop-livestock systems for environment friendly, especially the most important thing in biogas and bioslurry utilization is that it is included the national policy and continuously supported by the Government.

Acknowledgement

The research is part of the requirement towards a doctoral degree in Doctoral Program of Animal Science, Faculty of Animal Husbandry, University of Brawijaya, Indonesia. We would like to thank the DITLITABMAS Directorat General  of Higher Education, Ministry of Education and Cultural, Republic of Indonesia for give an opportunity and financial supported this research through doctoral disertation research grant. We would like to thank too the Rector of Sam Ratulangi University that recommendated this study for the grant.

References

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Received 1 February 2015; Accepted 8 March 2015; Published 1 April 2015

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