Saponifikasi dan Ekstraksi Satu Tahap untuk Ekstraksi Minyak Tinggi Linoleat dan Linolenat dari Kedelai Varietas Lokal

Asam linoleat (LA, linoleic acid, C18:2ω-6) dan asam alfa linolenat (ALA, alpha linolenic acid, C18:3ω-3) merupa- kan asam lemak tidak jenuh majemuk (PUFA, polyunsaturated fatty acid) esensial. Penelitian tentang kedelai varietas lokal sebagai sumber LA dan ALA sangat penting dalam rangka mengurangi ketergantungan terhadap produk minyak tinggi LA dan ALA impor. Akan tetapi, penelitian tentang ekstraksi LA dan ALA dari kedelai varietas lokal yang ada di Indonesia masih sangat terbatas. Teknik ekstraksi yang efisien diperlukan untuk meningkatkan kadar PUFA. Salah satu teknik untuk mengekstrak minyak tinggi LA dan ALA adalah kombinasi saponifikasi dan ekstraksi simultan atau saponifikasi-ekstraksi satu tahap.Penelitian ini bertujuan untuk mengungkap potensi kedelai varietas lokal sebagai sumber LA dan LA, dan untuk mengembangkan teknik saponifikasi-ekstraksi satu tahap. Kedelai varietas lokal, yaitu Panderman, Wilis, Kaba, Burangrang, dan Anjasmara, dianalisis profil asam lemaknya. Varietas yang digunakan lebih lanjut untuk saponifikasi- ekstraksi satu tahap didasarkan pada kadar LA dan ALA tertinggi. Selanjutnya, kondisi saponifikasi-ekstraksi satu tahap dioptimasi dengan menggunakan metodelogi permukaan respon dengan tiga faktor yaitu rasio air:tepung kedelai, suhu saponifikasi, dan lama saponifikasi. Respon yang dikaji adalah kadar LA dan ALA dalam minyak yang terekstrak. Hasil penelitian menunjukkan bahwa diantara kedelai varietas lokal yang diteliti, varietas Burangrang mempunyai kadar LA+ALA tertinggi (60,43 %). Varietas yang berbeda menunjukkan profil asam lemak yang berbeda dan kadar minyak (dalam bentuk asam lemak bebas) yang berbeda pula. LA merupakan asam lemak yang dominan untuk seluruh varietas kedelai. Rasio air:tepung kedelai, suhu saponifikasi, dan lama saponifikasi mempengaruhi respon yang bersifat kuadratik. Kondisi optimum tercapai pada rasio air:tepung kedelai 2,03:1, suhu saponifikasi 58,86 °C, dan lama sapon- ifikasi 92,27 menit. Respon kadar LA dan ALA (%) pada kondisi optimum berdasarkan prediksi adalah 68,47 % dan respon aktual 68,89 %. Minyak yang diperoleh mempunyai tingkat oksidasi yang rendah

Tropical Peatland Hydrology Simulated With a Global Land Surface Model

Tropical peatlands are among the most carbon-dense ecosystems on Earth, and their water storage dynamics strongly control these carbon stocks. The hydrological functioning of tropical peatlands differs from that of northern peatlands, which has not yet been accounted for in global land surface models (LSMs). Here, we integrated tropical peat-specific hydrology modules into a global LSM for the first time, by utilizing the peatland-specific model structure adaptation (PEATCLSM) of the NASA Catchment Land Surface Model (CLSM). We developed literature-based parameter sets for natural (PEATCLSM(Trop,Nat)) and drained (PEATCLSM(Trop,Drain)) tropical peatlands. Simulations with PEATCLSM(Trop,Nat) were compared against those with the default CLSM version and the northern version of PEATCLSM (PEATCLSM(North,Nat)) with tropical vegetation input. All simulations were forced with global meteorological reanalysis input data for the major tropical peatland regions in Central and South America, the Congo Basin, and Southeast Asia. The evaluation against a unique and extensive data set of in situ water level and eddy covariance-derived evapotranspiration showed an overall improvement in bias and correlation compared to the default CLSM version. Over Southeast Asia, an additional simulation with PEATCLSM(Trop,Drain) was run to address the large fraction of drained tropical peatlands in this region. PEATCLSM(Trop,Drain) outperformed CLSM, PEATCLSM(North,Nat), and PEATCLSM(Trop,Nat) over drained sites. Despite the overall improvements of PEATCLSM(Trop,Nat) over CLSM, there are strong differences in performance between the three study regions. We attribute these performance differences to regional differences in accuracy of meteorological forcing data, and differences in peatland hydrologic response that are not yet captured by our model.Peer reviewe

Hydrophysical properties of ombrotrophic peat under drained peatlands

Understanding the processes that control the retention and flow of water in peat soils is critical to the effective management of such soils from both agricultural and ecological perspectives. The water retention properties of peats collected from rubber-cultivated, oil palm-cultivated, and abandoned (uncultivated) areas in the vicinity of Kanamit Barat Village, Pulang Pisau District, Province of Central Kalimantan were characterized using the van Genuchten equation. Based on the parameters of α indicating a change in the water content as water potential changes and n indicating the rate of decreasing water content as water potential becomes more negative, the more decomposed peats in the rubber cultivated peatland lost their water relatively slowly at small negative pressure heads, while less decomposed peats in the oil palm-cultivated and abandoned peatlands lost their water more quickly. This reflects difference of pore-size distribution among different land uses of peatlands. The total volume of water retained by the unsaturated layers in the rubber-cultivated peatland was lower than that in the oil palm-cultivated and abandoned areas. Also, the residual water content was higher in the rubber-cultivated peatland compared to the oil palm-cultivated and abandoned areas. This implies that the proportion of the maximum volume of water being removed decreases as a result of agricultural activities in peatlands. This evidence shows that the moisture state of peat soil is greatly influenced by the degree of peat decomposition and water table fluctuation

SOCIAL CAPITAL IN THE RESTORATION OF PEATLAND ECOSYSTEMS: A CASE STUDY OF PULANTANI VILLAGE, SOUTH KALIMANTAN, INDONESIA

Social aspects such as coordination, cooperation, trust, concern, information flow affect the success of restoration activities. These elements are part of the social capital. The research aims to analyze the characteristics of individuals and social capital of the community in peatland restoration efforts. The object of this case study was the community of Pulantani village. Six indicators were used to assess individual characteristics, while 75 indicators were used to assess social capital. The number of respondents was determined using the Slovin formula. Data were analyzed using individual characteristic and social capital analysis. The individual characteristics obtained in Pulantani village fall into the moderate (>10 – 14). The indicators of age and length of residence have high values. This indicates the availability of a highly productive workforce and that they are locals, making this strength of the village. The level of social capital in Pulantani village is moderate (score= 233.59). The community of Pulantani village has strengths in trust, social norms, and sympathy and reciprocal action