Pengelolaan Lahan Gambut Untuk Pengembangan Kelapa Sawit Di Indonesia

Abstrak.Lahan gambut yang mempunyai sifat mudah rusak, pemanfaatannya harus berpedoman pada upaya pengembangan lahan berkelanjutan dengan konsep pembangunan yang “konstruktif-adaptif”. Pengalihan fungsi lahan gambut untuk keperluan lain berdasarkan kesesuaian dan kemampuan lahan serta penggunaan teknologi yang sesuai harus menjadi dasar dalam pengembangan lahan gambut ke depan. Dengan demikian, pemilihan teknologi dan komoditas yang tepat dan adanya upaya untuk menekan kerusakan lahan hingga sekecil mungkin menjadi sangat penting. Kelapa sawit merupakan salah satu komoditas yang mampu beradaptasi dengan baik pada berbagai jenis lahan, termasuk lahan gambut. Dengan teknologi pengelolaan air yang tepat, disertai peningkatan stabilitas bahan gambut dan serapan CO2 oleh tanaman pada kawasan pengembangan kelapa sawit, maka pemanfaatan lahan gambut akan memberikan faedah yang besar, tidak hanya untuk masa kini tetapi juga untuk masa mendatangAbstract.Peatlands with fragile properties should be used by following the guidance of sustainable land development with land usages concept of “constructive-adaptive” development. Conversion of peatlands for other land usages based on land capability and land suitability as well as the appropriate use of technology should be the basis for their future development. Thus, the selection of suitable technologies and commodities with the attempts to reduce the land damage to the lowest level is very important. Oil palm is one of the agricultural commodities that are able to adapt different types of land, including peatlands. With proper water management and the efforts to increase peat stability and CO2 sequestration in the area of oil palm development, the use of peatlands will provide a great benefit, not only for today but also for the future

ANALISIS LINGKUNGAN BIOFISIK LAHAN GAMBUT PADA PERKEBUNAN KELAPA SAWIT

ABSTRACTOil palm plantations at peatland are faced with problems of land degraded, low productivity and produced to green hause gas (GRG) emission. The objectives of this study were to land clearing effect of peatlands and to identify factors that affect the peatlands in the biophysical characteristics. This studi was conducted on District Bengkalis-Riau at marine and brakish peat. The data was collected using field survey and documentation. The descriptive analysis was used to ditermine biophysical characteristics and linier regresion was used to corelation perform important factors. The results of this study indicated that the biophysical characteristics peatland changed on the horizon profile, the thickness of the peat, the level of decomposition, water content, ash content, pH, C-organic and biomass. Water level as factor was changed at peatlands the biophysical characteristics

Functional Microbial Population on Oil Palm Rhizosphere in Riau Peatlands: Populasi Mikrob Fungsional pada Rhizosfer Kelapa Sawit di Lahan Gambut Riau

Oil palm growth in peatland may influence the presence of microbial populations. Root exudate is one of the organic compounds that is released by oil palm roots in the rhizosphere area where it can be used as a nutrient for microbes to survive in peatland. The study was conducted to study functional microbial population in the rhizosphere area of oil palm plantation aged <6, 9−15, and >15 years in Riau peatlands. The highest microbial populations were found in oil palm plantation aged <6 years at peat thicknesses of <3 and >3 m, which was respectively 10.3 x 106 and 5.7 x 106 CFU g-1. The highest cellulolytic microbial population was found in oil palm plantation aged <6 years at peat thicknesses of <3 and >3m, which was respectively 17.4 x 104 and 11.4 x 104 CFU g-1. The highest Azotobacter population was found in oil palm plantation aged >15 years at peat thicknesses of <3 and >3m, which was respectively 9.4 x 105 and 12.5 x 105 CFU g-1. The highest phosphate solubilizing microbial population was found in oil palm plantation aged <6 years at peat thicknesses of <3 and >3m, which was respectively 11.4 x 104 and 13.2 x 104 CFU g-1. The highest fungal population was found in oil palm plantation aged <6 years at peat thicknesses of <3 m and >3 m, which was respectively 11.4 x 104 CFU g-1 and 17.3 x 104 CFU g-1. The highest white-rot fungal population was found in oil palm plantation aged 9−15 years at peat thicknesses of <3 m and >3 m, which was respectively 8.7 x 103 CFU g-1 and 9.4 x 103 CFU g-1. In conclusion, the highest microbial population was dominantly found in oil palm plantation aged <6 years. Keywords: Microbial populations, oil palm plantation, peat thickness, rhizosphere areaPertumbuhan kelapa sawit di lahan gambut dapat mempengaruhi keberadaan populasi mikrob. Eksudat merupakan salah satu senyawa organik yang dihasilkan oleh akar sawit di rhizosfer, yang digunakan sebagai nutrisi bagi mikrob untuk bertahan hidup di lahan gambut. Penelitian ini dilakukan untuk mempelajari populasi mikrob fungsional pada rhizosfer kelapa sawit berumur <6, 9−15, dan >15 tahun di lahan gambut. Populasi total mikrob tertinggi pada ketebalan gambut <3 dan >3m ditemukan pada umur kelapa sawit <6 tahun masing-masing sebesar 10.3 x 106 dan 5.7 x 106 CFU g-1. Populasi mikrob selulolitik pada ketebalan gambut <3 dan >3 m 17.4 x 104 dan 11.4 x 104 CFU g-1 ditemukan pada kelapa sawit <6 tahun. Populasi Azotobacter tertinggi 9.4 x 105 dan 12.5 x 105 CFU g-1 ditemukan pada umur kelapa sawit >15 tahun pada kedua ketebalan gambut. Populasi mikrob pelarut fosfat pada ketebalan gambut <3 dan >3m tertinggi pada umur kelapa sawit <6 tahun, masing-masing 11.4 x 104 dan 13.2 x 104 CFU -1. Populasi jamur tertinggi pada kedua ketebalan gambut (<3 dan >3m) adalah 11.4 x 104 CFU g-1 dan 17.3 x 104 CFU g-1 terdapat pada kelapa sawit <6 tahun. Populasi White-rot fungi 8.7 x 103 CFU g-1 terdapat pada kelapa sawit 9-15 tahun dan 9.4 x 103 CFU g-1 pada kelapa sawit >15 tahun. Populasi mikrob tertinggi dominan pada kelapa sawit <6 tahun. Kata kunci: Populasi mikrob, kebun kelapa sawit, ketebalan gambut, rhizosfe

Loss of Soil Organic Matter, Lignocellulose and Microbial Population in Oil Palm Plantations Located at Different Slopes

Loss of soil organic matter can be caused by erosion triggered by soil compaction and high rainfall. The aims of  the study were to determine (1) the loss of soil organic matter, lignocellulose, and soil microbial population due to erosion and (2) the contribution of organic matter from oil palm fronds. In the current study, the erosion plots were built on the accessible inter-row (gawangan hidup) and inaccessible inter-row (gawangan mati) of oil palm plantations located at the slope of 6-10% and >10%. Soil organic matter, lignin, cellulose, and hemicellulose contents and total soil microbial populations were measured in the sediments collected from the erosion plots. The results showed that the loss of organic matter was higher in the accessible inter-row than that in the inaccessible inter-row. The addition of lignin, cellulose, and hemicellulose from oil palm fronds into the soil are 2.06 Mg ha-1 yr-1, 1.13 Mg ha-1 yr-1 and 1.02 Mg ha-1 yr-1, respectively. Total bacterial population in the sediments taken from the accessible inter-row was higher than that from the inaccessible inter-row, while the total fungal population in the sediments from the inaccessible inter-row was higher than that from the accessible inter-row. 

Fluks Metana dan Karakteristik Tanah pada Beberapa Macam Sistem Budidaya

Methane (CH4) is an important greenhouse gas that has a high heat trapping capacity thus potentially contribute to the global-warming.  Agriculture is considered among the responsible emission sources of CH4. Relationship among soil characteristics, soil microbes, and CH4 flux is very important in understanding the mechanism involved in the mitigation effects of certain agriculture practices. Results of this research showed that rice field produced the highest CH4 flux (7.4976 ± 0.5299 mg CH4-C m-2 h-1, n=3), while vegetable, sweet potato, yam bean and corn cropping produced lower CH4 flux (-0.7708 ± 0.6434 to 0.4605 ± 0.5255 mg CH4-C m-2 h-1, n=3). Nitrifier population among cropping systems was 3.13x103 to 3.17x104  MPN g-1 soil (dry weight), while denitrifier population was 3.77x103 to 1.17x105 MPN g-1 soil (dry weight).  There were no specific dominance proportion of nitrosomonas, nitrobacter, denitrifier and total propagule among cropping systems. The CH4 flux had highly correlation to soil water content (r = 0.951), soil pH (r = 0.852) and soil Eh (r = -0.982). Denitrifier had significantly correlation to soil pH (r = -0.635) and soil ammonium content (r =  -0.681).   Key words :  CH4 flux, cropping system, soil characteristic, soil microbe

Estimation of the Potential Carbon Emission From Acrotelmic and Catotelmic Peats

Agricultural development on peatland in Indonesia has been constrained by the presence of environment issues in relation to the release of greenhouse gases (GHGs) particularly carbon dioxide (CO2) and methane (CH4) to the atmosphere. This study was aimed to predict the potential carbon emission based on carbon stocks in acrotelmic and catotelmic peats with the reference of groundwater level of peatland.  The results showed that groundwater levels have played an important  role  in  carbon  release, which  has  close  relationship  with  water  regime  of  the upper  layer  of  peats  that influenced by oxidative and reductive conditions of the land.  From the layer that having groundwater level fluctuations during the period from rainy to dry season (acrotelmic peat), the emissions were mostly dominated by CO2 release, while from permanent reductive-layer (catotelmic peat) was not detected.  The decrease of groundwater level from -49.6 to -109 cm has clearly influenced carbon emission.  From each decreasing 1.0 cm groundwater level, CO2 emission measured during the period of February - October 2013 was calculated to yield about 0.37 Mg ha-1 yr-1.Keywords: Acrotelmic and catotelmic peat, carbon emission, groundwater level [How to Cite: Siti N, S Sabiham, B Nugroho and Di Nursyamsi. 2014. Estimation of the Potential Carbon Emission from Acrotelmic and Catotelmic Peats. J Trop Soils 19(2): 91-99. Doi: 10.5400/jts.2014.19.2.91]  [Permalink/DOI: www.dx.doi.org/10.5400/jts.2014.19.2.91] &nbsp

Estimation of the Potential Carbon Emission from Acrotelmic and Catotelmic Peats

Agricultural development on peatland in Indonesia has been constrained by the presence of environment issues in relation to the release of greenhouse gases (GHGs) particularly carbon dioxide (CO2) and methane (CH4) to the atmosphere. This study was aimed to predict the potential carbon emission based on carbon stocks in acrotelmic and catotelmic peats with the reference of groundwater level of peatland.  The results showed that groundwater levels have played an important  role  in  carbon  release, which  has  close  relationship  with  water  regime  of  the upper  layer  of  peats  that influenced by oxidative and reductive conditions of the land.  From the layer that having groundwater level fluctuations during the period from rainy to dry season (acrotelmic peat), the emissions were mostly dominated by CO2 release, while from permanent reductive-layer (catotelmic peat) was not detected.  The decrease of groundwater level from -49.6 to -109 cm has clearly influenced carbon emission.  From each decreasing 1.0 cm groundwater level, CO2 emission measured during the period of February - October 2013 was calculated to yield about 0.37 Mg ha-1 yr-1.Keywords: Acrotelmic and catotelmic peat, carbon emission, groundwater level [How to Cite: Siti N, S Sabiham, B Nugroho and Di Nursyamsi. 2014. Estimation of the Potential Carbon Emission from Acrotelmic and Catotelmic Peats. J Trop Soils 19(2): 91-99. Doi: 10.5400/jts.2014.19.2.91]