Interaction among progenies/provenances of sengon, arbuscular mycorrhizal fungi and riiizobial isolates grown on ultisol

Penelitian ini bertujuan untuk mengembangkan sengon (Paraserianthes falcataria) pada tanah ultisoL Penelitian ini jugs bertujuan untuk memperoleh isolat Rhizobium sp ataumilcorisa yang paling sesuai untuk perkembangan sengonkhususnya untuk jenis tanah ultisoL Koleksi Rhizobium sp dan mikorisa diutamakan berasal dari tempattempat penyebaransengon alam. Namun pengembanganberikutnya adalah memilih dan menguji bagi tempat-tempat yangpaling banyak untuk program HT/ yakni tanah Sengon dipilih dari penampilan terbaik tanaman ini di tanah ultisol. Ada 9 progeni yang dipilih dari tiga provenans yakni Morotai-Maluku, %Mena-Irian Barat dan Jasinga land race-Jawa Barat Ada tiga isolat amf dan Rhizobium sp terpillh yang dipergunakan untuk studi ini tersebut ditanam di pot tanah di dalam rupiah kaca. Isolat mikorisa terbaik yang telah diuji di tanah ultisol diutamakan untuk penelitian. Isolat Rhizobium sp yang terbukti mempunyai keunggulan di tanah masam (tanah ultisol) jugs merupakan pilihan utama untuk isolat. Hasil penelitian ini menunjukkan bahwa ada perbedaan nyata dalam: (i) seedlot dalam dan di antara provenans sengon. (ii) terdapat interaksi di antara progeni/provenans Pfalcataria, isolat amf dan rhizobium berpengaruh nyata terhadap pertumbuhan. Pertumbuhan terbaik pada umur 4 bulan diperoleh dari komposisi seedlot provenans Morotai (Maluku), kombinasi Glom us manihotis dan isolatBradyrhizobium PfLnU 16.2. Kombinasiterbailc ini dapat meningkatkan pertambahan biomasa sampai lebih dari lima belas kali dibandinglcan dengan kontrol, sedangkan kombinasi yang kurang bahkan dapat rnengurangi pertumbuhan tanaman inang. Dari hasil tersebut perlu disarankan untuk mempertimbangkanperanan kombinasiterbaik dariprogeni unggulan,mikorisa unggulan dan rhizobium unggulan pada tanah ultisol Kata kunci: progeni, provenans, mikorisa, rhizobium, ultisol, paraserianthes falcataria

Understanding the Impacts of Recurrent Peat Fires in Padang Island – Riau Province, Indonesia

Padang Island in Riau Province of Indonesia has been severely impacted by recurrent fires in 2014 and 2015, leading to severe peat ecosystem degradation and people´s livelihood. Therefore, analyzing the peat fires should not be isolated from socio-economic and local political context. Much has been written about peat fires  especially the magnitude of the fires, however the linkages between ecological and livelihood system of peatland ecosystem gained only scant attention. This paper analyzes how the drivers of peat fires are causing a steady decline in Padang Island and aims to provide more holistic understanding on how the drivers interplay and continue to feed the process of peatland degradation with its associated impacts on local economic development and people’s livelihood. Multidisciplinary approach was applied in this study. This includes remote sensing data analysis, analysis on related documents such as historical documents and regulations. Intensive fieldwork was conducted in the island in which series of FGDs and interviews were executed. We found that the global demands for agricultural commodities have led to massive peat drainage for monoculture farming on peat lands. The high dependency on global commodity market and monoculture farming has created livelihood vulnerability, especially because of the price fluctuation of agricultural products at global market. Moreover, the monoculture farming on peat lands tends to be unsustainable since it demands peat drainage, provides less options for sources of income and tends to marginalize indigenous knowledge about farming on peatland (paludiculture) which have been practiced for centuries in the island. Memahami Dampak Kebakaran Lahan Gambut yang Berulang di Pulau Padang-Provinsi Riau, IndonesiaIntisariPulau Padang yang terletak di Provinsi Riau, Indonesia mengalami kebakaran lahan gambut cukup parah dan berulang pada tahun 2014 dan 2015 yang mengakibatkan degradasi ekosistem gambut dan kehidupan masyarakat. Oleh karena itu, seharusnya analisis kebakaran lahan gambut tidak dapat dapat dipisahkan dari konteks sosial ekonomi dan politik lokal. Sudah banyak tulisan yang menganalisis tentang kebakaran lahan gambut terutama terkait dengan besarnya kebakaran, tetapi sangat sedikit yang menganalisis hubungan antara sistem ekologi dan sistem kehidupan masyarakat. Artikel ini menganalisis bagaimana faktor-faktor penyebab kebakaran lahan gambut juga mengakibatkan degradasi yang terusmenerus di Pulau Padang dan bertujuan untuk berkontribusi pada pemahaman yang lebih menyeluruh mengenai bagaimana faktor-faktor tersebut bekerja, saling terkait, dan secara terus-menerus mempengaruhi proses degradasi lahan gambut serta dampaknya terhadap pembangunan ekonomi lokal dan kehidupan masyarakat. Penelitian ini menerapkan pendekatan multi-disiplin yang meliputi analisis data penginderaan jauh, dokumen sejarah dan peraturan terkait. Penelitian lapangan dilakukan secara intensif di Pulau Padang, meliputi serial diskusi kelompok terfokus dan wawancara. Kami menemukan bahwa permintaan pasar global akan komoditas pertanian berkontribusi terhadap drainase lahan gambut skala besar untuk pertanian monokultur pada lahan gambut. Tingginya ketergantungan terhadap pasar global komoditas dan pertanian monokultur telah menciptakan kehidupan masyarakat yang rentan. Hal ini terutama karena besarnya fluktuasi harga komoditas pertanian di pasar global. Di samping itu, pertanian monokultur pada lahan gambut cenderung tidak berkelanjutan karena mensyaratkan pengeringan lahan gambut dengan drainase, menawarkan pilihan sumber penghasilan masyarakat yang lebih sedikit dan meminggirkan pengetahuan lokal tentang paludikultur yang sudah dipraktekkan selama berabad-abad di Pulau Padang

PROSPEK PENGGGUNAAN TANAMAN PENUTUP TANAH JENIS LEGUM SEBAGAI BAHAN PEMBENAH TANAH (The Prospect of the Use of Legume Cover Crop as Soil Amendment)

The effect oflegume cover crop on soil characteristics was studied to know the possibility of using legume cover crop as soil amendment for the next generation of Gmelina arborea Roxb. plantation forest Three species oflegume cover crop: Crotalaria anagyroides (CRY), Mucuna chochuchinensis (MC) and Colopoginium caeruleum (CC) were planted at the fonper field of G.arborea plantation forest CRY is not a creep tree and has a good suitability to grow well and fast to flower. The growth rate of Mucuna sp was relatively high and covered soil surface rapidly. The initial growth rate of Colopogium sp was relatively slow, but finally covered soil surface well, thick and remained for a long time. Biomass in CRY was the highest (28,5 tonlha), followed by MC (26,S tonlha) and CC (19 tonlha). Carbon content of each legume cover crop was about 50% of its dried weight biomass. Organic matter and C, N, P, K, Ca, Mg and Fe contents were higher than the other non-legume species in the plot. Soil characteristics were affected by legume cover croP? especially in the top layer. Legume cover crop can improve soil properties and become a good soil amendment for the next rotati</p

Drivers of Recurrent Peatfire in Riau and South Sumatera, Indonesia

Riau province once has been blessed with about 4 million Ha peatforest, making as among the largest peatland countries in Indonesia. Responding to economic development, most of the peatforest have been largely drained and the province have been among the most prone to recurrent peatfire area. There has been much debates on the patterns and root of causes (drivers) of peatfire, causing effort to curb recurrent peatfire are daunting task and even becoming a inconclusive high tension public debates. There has been much ambiguity on the drivers and the triggers. Poor availability of evidence of the peatfire patterns and their drivers making efforts to suppress the recurrent petfire and its policy intervention has never been effective. Using different techniques of remote sensing, we present here a number of evidences that peatland in Riau becoming more vulnerable to recurrent peatfire due to expanding large scale peatland drainage, intensified peatland-human interaction and poor peatland governance. We found also a similar pattern in a near areas in province of South Sumatera, to make confident that recurrent peatfire is a merely consequence of a systemic impact following adoption of paradigm of development to put peatland as among central farming areas to provide a globally traded commodities like crude palm oil (CPO) and pulp and paper

Wood Anatomical Features and Physical Properties of Fast Growing Red Meranti from Line Planting at Natural Forest of Central Kalimantan

High productivity fast growing species plantation establishment such as the line planting of red meranti (i.e Shorealeprosula and Shorea parvifolia) with intensive silviculture is one potential solution to improve wood supply for industries in Indonesia. However, the information of anatomical properties and wood properties of these two species related to the influence of the line planting system and tree growth rate is limited. This paper studies the anatomical features, wood cell proportions, fiber dimensions and physical properties of wood in radial variation in relation to the line planting effect and tree growth rate. Wood of the trees grown in the line planting system showed higher proportion of vessel element compared to those of wood from natural forest. The vessel diameter of wood from the line planting was also larger than that of in wood from natural forest. The specific gravity of wood from Shorea parvifolia grown on the line planting was higher than that of wood grown in natural forest. The variation of specific gravity on wood portion near to the pith of Shorea leprosula and Shorea parvifolia trees grown on the line planting was related to the variation of the cell wall thickness. The bigger diameter of trees grown or the faster growth rate in the line of planting at the same age shows the greater vessel diameter in wood of Shorea leprosula and Shorea parvifolia and greater specific gravity of Shorea parvifolia wood