Abstract. Karyati, Sarminah S, Karmini, Rujehan, Lestari VFE, Panorama WS. 2019. Silvicultural, hydro-orological and economic aspects of a combination of vegetative (Falcataria moluccana-Vigna cylindrica) and terrace systems in soils of different slopes. Biodiversitas 20: xxxx. Soil and water conservation techniques involving a combination of vegetative and mechanical systems will increase the benefits from both conservation aspect as well as economic aspect. This study was aimed at analyzing the silvicultural, hydro-orological and economic aspects of a combination of vegetative (Falcataria moluccana-Vigna cylindrica) and terrace system in soils of different slopes (a steep and a very steep slope gradient). The silvicultural parameters examined in this study were the ground coverage of V. cylindrica growth and survival rate, stem diameter and height of F. moluccana trees. The hydro-orological parameters included erosion rate, erosion hazard index, erosion hazard class, and erosion hazard level. The economic parameters included total cost, total revenue, and profit. The result showed that the survival rate, diameter increment and height increment of F. moluccana, and ground coverage of V. cylindrica in the land with the steep slope (>25-45%) was 90%, 2.02 cm year-1, 1.54 m year-1, and 80-90%, respectively. The erosion rate, erosion hazard index, erosion hazard class, and erosion hazard level in this steep slope was 0.38 ton ha year-1, 0.03 (low), I (very low), and very low, respectively. In the steeper ground (>45%), the survival rate of F. moluccana reached 90%, the V. cylindrica coverage was 70-79% and the diameter and height increment of F. moluccana was 1.63 cm year-1 and 1.19 m year-1, respectively. The erosion rate was 1.81 ton ha-1 year-1, erosion hazard index of 0.13 (low), erosion hazard class was I (very low), and erosion hazard level was low in the very steep slope land. The profit from V. cylindrica was Rp 3,865,000.00 ha-1 cropping season-1 and Rp 665,000.00 ha-1 cropping season-1 in steep slope and very steep slope, respectively. The application of the proposed combination of vegetative and terrace system could reduce surface runoff and erosion rate in the long term, in addition to providing short term economic benefits.

Imang N, Rujehan, Duakaju NN. 2018. Assessment of daleh swidden agriculture as an innovative alternative to conventional swidden under conditions of external pressure on local forest management in Kalimantan, Indonesia. Biodiversitas 19: 840-848. Swidden agriculture is still an important livelihood for millions of people in the tropics. In Kalimantan Island of Indonesia, swidden agriculture is currently facing many external pressures such as massive expansion of oil palm plantations, concession for industrial plantations, and non-availability of financial and political support from the government. The above external pressures which ignore local wisdom in forest and land management have reduced the land available for swidden agriculture. The external pressures, in turn, have shortened the cycle of swidden agriculture and decreased the productivity of swidden agriculture. The objectives of the present study are to assess socio-cultural and economic aspects of the innovative daleh agriculture as an alternative to conventional swidden agriculture under these conditions. The study was conducted in an indigenous Bahau Dayak community of East Kalimantan, Indonesia. Twenty swiddeners and 6 other key informants were interviewed for data collection. Research findings confirm that the expansion of oil palm plantations has ignored the wisdom in forest and land management, in general, and caused pressure on swidden agriculture, in particular. Under such pressures, daleh swidden agriculture may be effectively practiced because it can increase land productivity and is also culturally acceptable. Further, financial and facilitation support from district government is needed to improve the practice of swidden agriculture in the study area.

Agroforestri tradisional yang berkembang dari budaya lokal memiliki peran penting sebagai sumber pendapatan rumah tangga petani di Desa Mara Satu. Pendapatan merupakan indikator ekonomi petani karena besarnya pendapatan akan menentukan pemenuhan kebutuhan hidupnya, tetapi pendapatan juga ditentukan oleh nilai ekonomi dari komoditi atau produk agroforestri yang dihasilkan oleh petani. Potensi Agroforestri dapat dilihat dari dua aspek, yaitu potensi vegetasi penyusun agroforestri dan potensi ekonomi komoditi agroforestri. untuk potensi vegetasi penyusun agroforesti dengan melihat hasil hutan kayu dan hasil hutan non kayu, sedangkan potensi ekonomi dilihat dari nilai ekonomi dari produk agroforestri yang dihasilkan dari sistem agroforestri yang ada. Penelitian ini dilaksanakan di Desa Mara Satu Kecamatan Tanjung Palas Barat Kabupaten Bulungan Provinsi Kalimantan Utara. Metodologi yang digunakan adalah metode purposive sampling yaitu pengambilan sampel secara sengaja sedangakan penentuan jumlah sampel ditentukan berdasarkan teknik Slovin. Analisis data menggunakan deskriptif kuantitatif dan dimuat dalam bentuk tabel. Berdasarkan hasil penelitian dapat diketahui bahwa Volume total (potensi) tanaman agroforestri responden Desa Mara Satu adalah 797,18 m3 dengan Volume tegakan paling besar adalah tanaman Durian (Durio zibethinus) sebesar 270.34 m3. Potensi tanaman obat Desa Mara Satu memiliki total nilai ekonomi sebesar Rp. 177.099.000,- per tahun dengan potensi yang paling besar adalah jahe merah (Zingiber officinale Linn. var. rubrum)  yaitu sebesar Rp. 81.600.000,- per tahun. Total nilai ekonomi produk tanaman agroforestri dari 37 responden petani Desa Mara Satu adalah sebesar Rp. 3.385.889.000,- per tahun.

Rujehan, Matius P. 2018. Potential and management strategy of floral biodiversity in the coastal areas in East Kalimantan,Indonesia. Biodiversitas 19: 1130-1137. Some issues such as land clearing and mining activities often arise in the coastal areas of BukitSoeharto Forest Park, East Kalimantan, Indonesia that serves as a water catchment area. The latest land cover in this area was dominatedby bush or shrub and forest cover was reduced. This research was conducted in Tanah Merah Coast and around Samboja Reservoir inthe coastal area of Bukit Soeharto Forest. The purposes of this study were to determine the potential diversity of flora in the two regionsand to develop management strategies in order to maintain or even to improve the diversity of flora. The method used in this researchwas a survey using vegetation analysis and SWOT analysis. The results showed that the species of saplings and trees dominating theforest area of Tanah Merah Coast was Nauclea orientalis, while Cratoxylum arborescens was the most prominent species of seedlings.On the other side, the forest around Samboja Reservoir was dominated by Campnosperma auriculata for trees or adult communities,Ficus retusa for saplings and Dyera costulata for seedlings. Both species diversity (H') and evenness index (E) of these areas werecategorized as medium. Management strategies needed to maintain and improve the diversity and evenness of existed flora consist of S-Ostrategy that aims to improve the ecological functions of the area that can provide economic benefits, S-T strategy proposes cooperationwith local communities to develop alternative economic activities, W-O strategy utilize the funding opportunities from donor agenciesfor forest management and W-T strategy includes efforts to improve human resources through training in collaboration with donor agencies.

Abstract. Willard K, Aipassa MI, Sardjono MA, Rujehan, Ruslim Y, Kristiningrum R. 2022. Locating the unique biodiversity of Balikpapan Bay as an ecotourism attraction in East Kalimantan, Indonesia. Biodiversitas 23: 2342-2357. Balikpapan Bay is rich in biodiversity and natural beauty that present unique opportunities for the developing ecotourism industry in East Kalimantan, Indonesia. This study aimed to identify biodiversity hotspots with potential as ecotourism attractions. Four field surveys by boat, each survey taking between 10 to 22 hours duration, tracked the river and tidal flow through the Bay, recording highlights of biodiversity at 19 defined observation points. The study results recorded observations on five species listed in the IUCN protected species classification, namely: Lesser Adjutant Stork (Leptoptilos javanicus) - classified as a Vulnerable species; Proboscis Monkey (Nasalis larvatus), Irrawaddy Dolphin (Orcaella brevirostris) and Green Turtle (Chelonia mydas) - classified as Endangered species; and the Hawksbill Turtle (Eretmochelys imbricata) - classified as Critically Endangered. In addition, details were recorded of a unique variant of the mangrove species Rhizophora apiculata, with leaves that have a vibrant yellow color instead of the usual green. Combined with great views, including at night when there are enchanting displays of Fireflies (Lampyridae) on several riverbanks, the biodiversity of the waterways results in Balikpapan Bay having great potential as an ecotourism destination. Therefore, this study provides useful input to relevant agencies charged with responsibility for conserving and managing the natural resources of the Bay for the benefit of communities who stand to gain economically from developing this ecotourism potential.