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Dischidia is an epiphytic plant, it is used as herbal medicine and has economic value. In addition, Dischidia also has an ecological function. Moreover, some species of Dischidia are endemic in a particular region. Various forest types occur in Bangka Island serves as natural habitat for this epiphytic plant. This research aimed to record the diversity and abundance of Dischidia and analyze those environmental factors which affect its abundance. The research was conducted in August – September 2016 at Bangka Island. Three plots of 20 × 20 m² were placed with a minimum interval of 50 m in the habitat where Dischidia are found. The species diversity and abundance of Dischidia as well as abiotic factors such as temperature, humidity, light intensity, wind speed, and altitude were recorded in these plots. The vegetation structure was analyzed based on index of diversity, index of dominancy and index of evenness. Data on the environmental condition and abundance of Dischidia were then analyzed using Canonical Correspondence Analysis (CCA) method with Canoco 4.5 software. Five species of Dischidia were found in Bangka Island that are Dischidia bengalensis , Dischidia imbricate , Dischidia nummularia , Dischidia rafflesiana , and Dischidia hirsute . Dischidia is found in 14 species of host plants. D. imbricate (23 individual plants) occurred in the heath forest at Pejem showed the highest abundance. Epiphytic fern plants, the Asplenium nidus (27 individual plants), was the dominant epiphytes found in the host tree of Dischidia The CCA showed that light intensity, temperature and humidity influenced the abundance of Dischidia .

Allelopathy is a natural strategy for the protection or inhibition toward other vegetation through the release of chemicals into the environment. Alpinia malaccensis is thought to be capable of carrying out allelopathic mechanisms, as this species is found to grow well on land invaded by Merremia peltata. Invasive type control with alleopathic mechanism is an alternative to consider as it does not leave a potential residue as a contaminant of soil as it is chemically controlled. The study attempt to investigate the content of A. malaccensis allelochemicals and analyzed the alelopathy potential of A. malaccensis on seed germination and seedling growth of M. peltata. Research method used completely randomized design with 6 replicates for seed treatment and three replicates for seedling treatment. Seeds which have relatively similar size and weight were obtained from the field. Seeds were germinated in petri dishes that have been coated by filter paper, each petri dish contained 6 seeds of M. peltata. The treatment of the seeds germination was performed by giving 3 ml of rhizomes and leaves extracts of A. malaccensis (control, 30 g/L, 60 g/L, 90 g/L, 120 g/L, and 150 g/L). The treatment of the seedlings was performed by giving 30 ml of rhizomes and leaves extracts of A. malaccensis (control, 50 g/L, 100 g/L, 150 g/L, and 200 g/L). The analysis of chemical compounds of fresh rhizomes and leaves showed that A. malaccensis contains alcohol, amide, fatty acid, phenol, ketones, and terpenoids. Rhizomes and leaves extracts 150 g/L of A. malaccensis showed the highest inhibition in germination, dry weight, plumule and radicle length of M. peltata sprout parameters. Rhizomes and leaves extract 200 g/L of A. malaccensis showed the highest inhibition in tendril length, amount of leaves, length and width of M. peltata leaves parameters. To be more efficient, application in the field should use low concentration of extracts that can inhibit the M. peltata. Results of this study are expected to provide information about alternative solutions to suppress the invasion of M. peltata to preserve ecosystems of Bukit Barisan Selatan National Park (BBSNP) in Lampung.

Adiantum lunulatum Burm. f. has been widely used in aesthetic needs and medical fields. Detail information about the life cycle of A. lunulatum is still unknown, particularly about its gametophyte generation. Present work aimed to study and compare the growth and development of the gametophytes of A. lunulatum from dry and humid areas. Research method consists of two stages: (1) Spores were collected from two locations, Pasuruan and Bogor and (2) Spores were planted and observed the growth and development of gametophyte. The result showed that natural habitat of the plant in various dry and humid areas, affecting the rate of growth and development rates of A. lunulatum gametophyte. The gametophyte from the dry area showed faster rate of growth and development than that of humid areas. The spores collected from dry area need 9 weeks for germination, growth, and development while the spores of humid area took 22 weeks.

Pandam Gadang has tropical forests which become the habitat of Rafflesia ( Rafflesia arnoldii ) which grows as a parasite of Tetrastigma (Vitaceae). Study on R. arnoldii is needed since its population continuously decrease as a result of habitat destruction of its host. The aim of the study was to determine habitat conditions, vegetation structure, and characteristic of the host species of Rafflesia ; to identify environmental factors, and determine the Rafflesia habitat suitability in Pandam Gadang Koto Tinggi Village, West Sumatra. Analysis of vegetation in the habitat where Rafflesia grows using a circular plot. The number of individuals Rafflesia found was recorded and completed with observations of its morphology. Micro-climate measurements were carried out together with data collection in the field. Flower morphological analysis was descriptively presented. Environmental parameters were-processed with Canoco software 4.56 using Canonical Correspondence Analysis. Habitat suitability was analyzed using Maximum Entropy. The 17 Rafflesia individuals found on Pandam Gadang were R. arnoldii , known as "Cendawan Biriang", living parasitically on Tetrastigma leucostaphylum . The results of analysis of vegetation in the Rafflesia habitat showed that there were 250 individual plants consisting of 42 species and 21 genera. Seedlings most dominant was Lauraceae, belt were dominated by Moraceae, Meliaceae, and Euphorbiaceae. Trees were dominated by Euphorbiaceae, Moraceae, and Meliaceae. Existence and survival of R. arnoldii depended on soil pH 7-7.8, environmental humidity 83-91.8 % and distance from the nearest river 3-27.8 m.