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Arbuscular mycorrhizal fungi (AMF) and biodegradable pots are environmentally friendly and enhance plant growth in adverse soil conditions. These studies explored AMF interactions and biodegradable pots in physiology, growth, and the uptake of nutrients in Samanea saman seedlings. The present research interactive effects of biodegradable pots with different compositions and raw material sizes with and without AMF inoculation on S. saman grown in silica post-mining soil media. Results indicated AMF inoculations significantly improved leaf chlorophyll content, photosynthetic rate, heights, diameters, biomass, as well as nutrient absorption of S. saman as compared with non-inoculated plants in biodegradable pots. AMF and biodegradable pots composed of 15% used newspaper, 70% compost, 5% cocopeat, and 10% rock phosphate showed the best results and increased the leaf chlorophyll content, photosynthesis rate, height, diameter, and total biomass of the plants by 161.1%, 208.7%, 263.6%, 118.1%, and 269.9%, respectively, compared to biodegradable pots composed only of used newspaper. Additionally, uptake of the nutrients nitrogen, phosphate, potassium, and magnesium increased by 365%, 800%, 369%, and 250%, respectively. By the fourteenth week after transplanting, the C/N ratio of the organic pot decreased significantly. Thus, AMF and biodegradable pots containing compost and rock phosphate interact positively and enhance the growth of S. saman under adverse soil conditions. These findings suggest that biodegradable pots containing compost and rock phosphate show potential as more environmentally friendly replacements for plastic bags (polybags) as growth medium containers for seedling production.

A biodegradable seedling container was developed to minimize plastic waste in the field during post-mining land revegetation activities. Therefore, this study aims to evaluate the physiological response and growth of Samanea saman grown in a biodegradable seedling container filled with post-silica mined soil media. A factorial experimental design was used with two factors, namely (1) basic raw materials, namely recycled newspaper, compost, and cocopeat, and (2) size of raw materials, including 5 mesh, 10 mesh, and 8 mesh. The parameters measured were photosynthetic rate, leaf greenness index, transpiration rate, height, and diameter of S. saman seedlings. The results showed that the interaction between the composition and size of basic raw materials of the biodegradable seedling container significantly increased the photosynthetic rate, leaf greenness index, transpiration rate, height, and diameter of seedlings. There was also a positive correlation between the rate of photosynthetic and leaf greenness index (r = 0.838). Furthermore, the C/N ratio of the biodegradable pot varied depending on the composition of materials used. After two months, the C/N ratio decreased, indicating that decomposition processes had occurred. Analysis of the biodegradable seedling container showed that it contains less than 0.08 mg Pb kg-1, which was considered a non-toxic element for plant growth.

Deteriorated seeds can be improved by invigoration treatment, including gamma-ray irradiation by Cobalt-60 (60Co). The purpose of this study was to determine the proper dose of gamma-ray irradiation (60Co) to increase the decreased vigor of suren (Toona sureni (Blume) Merr.) seeds. This study uses a factorial completely randomized design (CRD) with aging and irradiation as the treatments. Aging factors consisted of 0, 2, and 4 days. Irradiation factor consisted of 7 levels, namely 0, 5, 10, 20, 40, 80, and 100 Gy, repeated four times. The parameters observed were the electrical conductivity, germination percentage, germination speed, and seedling height. The results showed that Seed aging treatment significantly affected Suren seed germination with 75% (2 days aging) and 56% (4 days aging) germination. The 40 Gy dose of gamma-ray irradiation could increase germination percentage and germination speed of low suren seed vigor increasing 51.42% and 60.21%, respectively. Simultaneously, the cell membrane damage of stored suren increased with gamma-ray irradiation treatment of more than 40 Gy based on electrical conductivity. In seeds with high germination, such as seeds without aging and seed aging for two days with a germination percentage of 80% and 75%, respectively, the invigoration treatment was not effective. Invigoration treatment was effective in increasing the deteriorated or low viability and vigor of the suren seeds.

Forest exploitation and conversion to other landuse may cause lost of biodiversity, including most important dipterocarp trees species, i.e. Shorea leprosula and Shorea laevis. The objective of this study was to determine the rarity status of the two important shorea species, i.e. S. laevis and S. leprosula, based on IUCN criteria, their habitat characteristics, and their association with other species, as one of the basis for determining their conservation strategy as a part of forest management. This study was conducted in three types of ecosystem (virgin forest, secondary forest, and fragmented forest) in Muara Teweh, Central Kalimantan. Methodology used in this research includes vegetation and tree diversity analysis. Study results showed that both S. laevis and S. leprosula were included within category of “low risk” in the 3 types of ecosystem in the forest area being studied. Habitat characteristics which determined the absence of S. laevis in the virgin forest habitat was the soil permeability which was too low, whereas other soil chemical and physical properties in the three types of ecosystems were relatively similar. Presence of S. laevis were positively associated with species of S. uliginosa, Dialium platysepalum, Dipterocarpus ibmalatus, Palaquium rostatum, Vatica rasak, Adinandra sp., and Memecyclon steenis. On the other hand, S. leprosula were positively correlated with S. kunstleri, Castanopsis sp., Shorea sp., Quercus bennettii, Castanopsis argentea, and D. hasseltii.Keywords: threatened species, Shorea spp., habitat characteristic, ecosystems type, associated species

Forest exploitation and conversion to other landuse may cause lost of biodiversity, including most important dipterocarp trees species, i.e. Shorea leprosula and Shorea laevis. The objective of this study was to determine the rarity status of the two important shorea species, i.e. S. laevis and S. leprosula, based on IUCN criteria, their habitat characteristics, and their association with other species, as one of the basis for determining their conservation strategy as a part of forest management. This study was conducted in three types of ecosystem (virgin forest, secondary forest, and fragmented forest) in Muara Teweh, Central Kalimantan. Methodology used in this research includes vegetation and tree diversity analysis. Study results showed that both S. laevis and S. leprosula were included within category of “low risk” in the 3 types of ecosystem in the forest area being studied. Habitat characteristics which determined the absence of S. laevis in the virgin forest habitat was the soil permeability which was too low, whereas other soil chemical and physical properties in the three types of ecosystems were relatively similar. Presence of S. laevis were positively associated with species of S. uliginosa, Dialium platysepalum, Dipterocarpus ibmalatus, Palaquium rostatum, Vatica rasak, Adinandra sp., and Memecyclon steenis. On the other hand, S. leprosula were positively correlated with S. kunstleri, Castanopsis sp., Shorea sp., Quercus bennettii, Castanopsis argentea, and D. hasseltii.