UPV Digital RepositoryUPV-DRUniversity of the Philippines Visayas
 

Undergraduate Theses

Permanent URI for this collectionhttps://hdl.handle.net/20.500.14583/13

Browse

Filters

2000 - 200912010 - 20191

Settings

AGROVOC Keyword: search.filters.agrovoc.ecosystems

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Sediment organic matter, nitrogen, and phosphorus of four tivers in Miagao, Iloilo
    Cahilig, Guen Gian D. (Department of Chemistry, College of Arts and Sciences, University of the Philippines Visayas, 2019-06)
    The four rivers of Miagao are examples of aquatic areas where sediment pollution can be related and mostly caused by anthropogenic and non-point sources. The four rivers of Miagao, namely Bacauan, Naulid, Oyungan and Tumagbok rivers, were assessed and observed to have low levels of water due to the dry season, presence of water stagnation due to dikes; other factors such as discharges from domestic activities and livestock wastes, and thick vegetation are also present in the river. The relevance of this study is to provide baseline information about the levels of organic matter, NH4-N, and available phosphorus present in the river, provide public knowledge about the negative impacts of excessive levels of those parameters; and locate possible sources of the pollution through the values obtained. For the total phosphorus concentration present in river sediments, the values are ranging from 0.0648 ppm to 0.154 ppm. Therefore, the values of the available phosphorus are harmful and can cause eutrophication to the river. However, for the values of organic matter and nitrogen, it was reported to be not harmful to the river but can still contribute to the excessive nutrient levels and eutrophication of the river.
  • Thumbnail Image
    Item
    A community study of mangroves in Brgy. Caliling, Cauayan, Negros Occidental
    Barredo, Sherry Marie P. (Division of Biological Sciences, College of Arts and Sciences, University of the Philippines Visayas, 2000-03)
    The species distribution of the mangrove community in Brgy. Caliling, Cauayanz Negros Occidental was studied using the transect line plot method with three plots for each of four stations established. Both stations 1 and 4 were located landward, while stations 2 and 3 were located seaward. Community structure Is described in terms of the following parameters; basal area, number of trees per hectare, importance value, relative density, relative frequency, frequency of species and relative dominance. Variations in these parameters are correlated with physico-chemical factors such as the air, water and soil temperature, water depth, salinity and pH. Ten true species were found In the mangals of the coastal environment of Brgy. Caliling, Cauayan, Negros Occidental. They were Avicennia aiba, Avicennia Janata, Avicennia manna, Campostemon phiiHpinensis, Excoecaria agallocha, Osbomia octodonta, Nipa fruticans, Brugeria cylindrica, Rhizophora apiculata and R. mucronata. Standard Basal Area was highest in Station 3 with 7.54 m/ha. In terms of zonation, the landward zone was found to have the highest Stand Basal Area with 11.15 m/ha. Station 2 had the highest density value of 33.92 %, whereas in terms of zonation, both the middle and seaward zone had the density value of 36.20 %. Avicennia marina was found to be the most dominant species and was observed to occupy sites with hypersaline conditions, in silty clay to muddy substratum, which may or may not be inundated by tidal flow most of the time.