Volume 21 Nos. 1 & 2
Plant diversity profile of the Lobo Watershed in Lobo, Batangas
Plant diversity assessment for Lobo Watershed in Batangas Province was conducted to determine species composition and diversity levels. Quadrat sampling technique was used to evaluate the vegetation. Vegetation parameters collected in the field include species identity, number of individuals, and diameter at breast height of trees. Indices such as Shannon-Wiener Diversity, Equitability and Species Richness were all determined for diversity examination.
One hundred eighty one species belonging to 137 genera under 66 families were recorded. Family Fabaceae was the most represented in the landscape with 19 species. Of the 137 genera recorded, genus Ficus of the family Moraceae registered the highest. The mean Shannon-Wiener Diversity and Evenness Indices are 1.71 and 0.79, respectively, corresponding to very low diversity based on modified Fernando Biodiversity Scaling System. Similarly, there are seven tree species in the watershed that are listed in the 2006 IUCN Red List of Threatened Species which include the endemic Tectona philippinensis and Vitex parviflora, among others.
Landscape approach to water quality assessment and river ecosystem classification: an exploratory approach
Lian-Palico River in Nasugbu, Batangas and Tanay River in Tanay, Rizal, both classified as Class C rivers, were included in this study. The state of the two river systems was assessed using water quality index and by identifying the presence and/or absence of aquatic macroinvertebrates and the current uses of the water. The two river systems were found to have very high level of coliform and the organic pollutants were way above the limit for Class C water. The low level of dissolved oxygen in the lower reach of Lian-Palico River, classified as a Very Bad river, can trigger fish kill anytime. Tanay River also showed very high level of total and fecal coliform. It is in medium state bordering from good to bad condition. Pollution sensitive families of insects in the river need to be further studied as they serve as useful indicators on the health condition of the river, particularly in far areas where chemical and biological analysis is a problem. Modifying the current system of river classification to reflect the present condition, constraints and problems is recommended.
Seed technology protocol for dungon (Heritiera sylvatica Vidal)
The study determined the processes involved in dungon seed technology from fruit collection to seed storage. Fruits and seed characteristics such as size, shape, presence of wings and colors were described. The average number of seeds from brown fruits with intact pericarp was 720/kg and 920/kg for extracted seeds. Seeds from yellow-brown fruit with intact pericarp was 540/kg and 780/kg for extracted seeds. Initial moisture content (MC) of extracted seeds from the brown fruit was 43.95% and 54.41% for seeds from the yellow-brown fruit. Initial germination of seeds extracted from brown fruit and pretreated with pericarp removal (PR) obtained the highest germination of 89% while seeds with pericarp intact (PI) had only 69% germination. Seeds from the yellow- brown fruits treated with PR and PI attained 34.87% and 21 % germination, respectively. Percent MC of extracted seeds from both samples was significantly affected by maturity index, duration of drying, and storage. Moisture content of seeds from yellow-brown fruit sample was significantly higher (38.90%) compared with 33.44% MC of seeds from brown fruit sample. For both maturity indices, rapid drying of the seeds were noted as sampling duration increased from 0 to 28 days. Percent germination of extracted seeds was also affected by maturity index, pretreatments, and sampling duration. Germination rate decreased as drying and storing period increased to 28 days, regardless of the maturity index used. Based from these results, it was concluded that dungon seeds have a recalcitrant type of storage physiology.
Pre-treatments in enhancing germination of molave (Vitex parviflora Juss.) seeds
To determine the best pre-treatment for molave seeds, a short term study in enhancing germination was conducted. Four pre-treatments were used: soaking in tap water overnight (T7), soaking in 15% sulfuric acid (H2S04) for 30 minutes and soaking in tap water overnight (T2), soaking in 15% hydrochloric acid (HCl) for 30 minutes and soaking in tap water overnight (T3), and alternate wet and sundrying for six days (T4). Treatment 4 obtained the highest germination of 91.4 % which is significantly much better compared with T2 (65.66%), T3 (63.20%) and T1 (43.20%). Differences between acid treatments (T2 and T3) were insignificant but significantly different from T1. Based from the results, alternate wet and sundrying for six days is the best pre-treatment for molave seeds.
A preliminary study on the floristic composition and structure of a lowland evergreen rainforest in Mt. Magdiwata, Agusan del Sur, Philippines
Floristic composition, forest structure and habitat preferences in a lowland evergreen forest in Northeast Mindanao is presented based on results of a botanical inventory that employed a combination of Gentry Plot and Braun-blanquet methods on ridge and slope communities. A total of 439 morpho-species belonging to 108 families are enumerated with 120 endemic species, from which 26 taxa are confined to the island of Mindanao. Exploration of Mt. Magdiwata yielded a new species of orchid- Euphlebium rhodochilum Ferreras & Coates and a new range extension forCynometra copelandii (Elmer) Elmer. Importance Values, diversity indices, a floristic checklist and a list of threatened species based on the IUCN, DAO 2007-1 and CITES I, II and III are also provided.