Land characteristics and land suitability assessment for Styrax sp. in Humbang Hasundutan Regency, North Sumatra, Indonesia.

Styrax sp. is a valuable latex-producing plant in North Sumatra Province, Indonesia, which requires sustainable land use practices to maintain its production and ecological value. This study aimed to assess the land characteristics and suitability of Styrax sp. in Humbang Hasundutan Regency, North Sumatra Province, to support the development of sustainable land use practices for the cultivation of this plant. The study employed a survey method to collect soil samples and evaluated the land suitability using a matching method and Geographic Information System (GIS) techniques. The results showed that Styrax sp. had moderately suitable land suitability in three villages in Humbang Hasundutan Regency. The limiting factors for land suitability were identified as rooting media, nutrient retention, water availability, and erosion hazard. These findings have important implications for the development of sustainable land use practices for Styrax sp. cultivation in the region, which can contribute to the conservation of this valuable plant species and the maintenance of ecological balance. Overall, this study provides valuable insights into the land characteristics and suitability of Styrax sp. in North Sumatra Province and highlights the importance of sustainable land use practices for the conservation of valuable plant species.

Properties of wood composite plastics made from predominant Low Density Polyethylene (LDPE) plastics and their degradability in nature.

To address concerns over plastics in the global environment, this project produced three wood plastics composites (WPCs) which could divert plastics from the waste stream into new materials. The three materials made had a ratio of 85%:15%, 90%:10%, and 95%:5% low density polyethylene (LDPE) to wood powder and were produced using the dissolution method. Physical and mechanical properties of each WPC were evaluated according to Japanese Industrial Standard (JIS) A 5908:2003. Their degradation in nature was evaluated through a graveyard test and assay test conducted in Coptotermes curvignathus termites. Results showed that density, moisture content, thickness swelling and water absorption of the WPCs fulfilled the JIS standard. The mechanical properties of these composites also met the JIS standard, particularly their modulus of elasticity (MOE). Modulus of rupture (MOR) and internal bonding (IB) showed in lower values, depending on the proportion of wood filler they contained. Discoloration of the WPCs was observed after burial in the soil with spectra alteration of attenuated transmission reflectance (ATR) in the band of 500-1000 cm-1 which could be assigned to detach the interphase between wood and plastics. As termite bait, the WPCs decreased in weight, even though the mass loss was comparatively small. Micro Confocal Raman Imaging Spectrometer revealed that termite guts from insects feeding on WPCs contained small amounts of LDPE. This indicated termite can consume plastics in the form of WPCs. Thus WPCs made predominantly of plastics can be degraded in nature. While producing WPCs can assist in decreasing plastics litter in the environment, the eventual fate of the LDPE in termites is still unknown.

Safety Test of Agarwood Leaves Tea (Aquilaria malaccencis Lamk.) Through Skin Sensitization Test on Albino Rabbit.

BACKGROUND: Agarwood tree (Aquilaria malaccensis Lamk) is a tree from the Thymeleaceae tribe that has a high selling value. The part that is often used is the sapwood of the agarwood tree, used as a base for perfumes and traditional medicines. Agarwood farmers in Langkat have used their leaves as tea drinks, brewing aloes leaves. Before being widely produced by the community, it is necessary to test the safety of agarwood leaf tea products through skin sensitization test. AIM: To find out whether steeping aloes leaves irritate the skin or not. METHODS: The test method using test animals namely albino rabbits as many as 15 tails, consisting of 4 test groups 1 group there were 3 test animals and 1 control group, induced with Freund's Complete Adjuvant (FCA) by intradermal and topical injection with a test position of 1.3%, 2.6%, 3.9% and 5.2% to form an immune response, then a Challenge test. The level and degree of skin reaction were assessed based on the Magnusson and Kligman scales. RESULTS: From the observation for 72 hours there was no change in the skin of the test animals after exposure to the test doses, indicating that the agarwood leaf tea is safe to consume if the tea is on the skin, the skin will not experience irritation. CONCLUSION: Testing on albino rabbits with four different doses did not show an irritating effect on the skin. Observation also shows that there is not a single bit that can affect intradermal to challenge testing so it was safe for consumption.