Thousands of tons of bagasse ash and lime sludge which have potential cementitious properties are generated from the two sugar milling companies in Bukidnon and are currently dumped in their respective open disposal sites. This study aimed to examine the potential utilization of bagasse ash and lime sludge as the partial replacement (up to30%) of Ordinary Portland Cement (OPC) in concrete. The results showed that the compressive strength of concrete, using bagasse ash and lime sludge as the partial replacement of OPC, failed to meet the minimum requirement of 21 MPa which is set by the National Structural Code of the Philippines (NSCP) (2010), except for samples using 10% of lime sludge as the partial replacement of cement (T4). Moreover, the blending ratio of 40% bagasse ash to 60% lime sludge as a partial replacement of OPC showed promising results. However, further studies should be conducted to determine
the effect of different blending ratio of bagasse ash and lime sludge and water cement ratio in order to study their distinctive effect during the pozzolanic reaction.
Keywords: blending ratio, cement, eco-concrete, industrial wastes
The three lakes in Bukidnon, namely Lake Pulangui, Napalit, and Apo, were assessed for their bio-physicochemical condition and fisheries status during wet and dry months of 2010-2011. Lake Apo had the highest transparency and depth which are characteristics of an oligotrophic lake. Pulangui Lake had the highest temperature, hardness, dissolved oxygen, pH, CO2, and total alkalinity. Primary production (tons C/km2/yr) in Pulangui lake was the highest (43,946), followed by Napalit (26,981) and Apo (25,229). Using the Trophic State Index, which is based on chlorophyll a content, Lake Apo was classified as an oligotrophic lake while Napalit mesotrophic and Pulangui were identified as a eutrophic lake. The three lakes had both the local and exotic fish species, but only in Pulangui Lake the janitor fish was found. Pulangui had the highest fish catch (kg/person/day) (3-15) with 378 fishermen followed by Napalit(3.26-3.90) with 16 fishermen and Apo (0.1) with only two fishermen. Tilapia was the main catch, and gill net was the most commonly used fishing gear. The three lakes have water quality values suitable for fish culture. The estimated potential fish production of the three lakes was higher than their present fish catch. These findings suggest that the present bio-physicochemical resources of these lakes may still support aquaculture development.
Keywords: Physicochemical, Chlorophyll a, primary production, fish production, Lake Trophy
A study was conducted to determine the diversity and status of trees in a the one-hectare plot of Mt. Musuan, Bukidnon. Six sampling plots, measuring 20 x 20 m area within 1– ha plot, were established to compute the diversity index and generate tree profile.The specimens collected were classified and identified using the taxonomic keys, journals, and monographs. Assessment of trees was determined based on the International Union for Conservation of Nature (IUCN) and the list of Philippine threatened plants. Inventory of trees in one-hectare plot revealed 77 species which were placed in 65 genera, 36 families, and with a total of 419 individuals. Sampling plots with a total area of 2400 m2 showed 30 species, 28 genera, and 22 families. Senna spectabilis
(DC.) H.S. Irwin & Barneby represents 15% (63 individuals) of the total number of individuals. Furthermore, the mean of 8.1 species/20 x 20 m plot was recorded. Species’ diversity of trees in different locations showed that it had a mean diversity value of H = 0.77. In four sampling plots, S. spectabilis
showed the highest species importance value (SIV) while in two other plots Kleinhovia hospital L. and Oroxylum indicum
(L.) Kurz obtained the highest SIV. Assessment of conservation status of trees showed one critically endangered species (Pterocarpus indicus
Willdenow), three vulnerable species, four endemic species, 17 depleted species, five common species, four rare species, and 32 economically important species.
Keywords: Inventory, Species Richness, Status, Tree Profile
Determination of runoff and sediment yield in agriculturally active catchment like Mapawa at Lantapan, Bukidnon is important, considering the soil sustainability and productivity. The Geospatial Interface for Water Erosion Prediction Project(GeoWEPP) model was applied and calibrated in this study. The site’s average elevation was 1,258 meters above sea level with a slope ranging from 0.5 to 75%.Georeferenced datasets were prepared corresponding to climate, slope, land management, and soil properties. Climate input file was processed from a one-year (2002) localized data set using the breakpoint climate data generator (BPCDG). Slope input file was derived from digital elevation model (DEM). Soil and management input files were derived from field surveys. Separate database files were also created to link WEPP with GIS tool. After series of calibration, runoff and sediment yield were predicted at an average value of 11,121.0 m3and 11.2 tons, respectively. The model was validated with Root Mean Square Error (RMSE) (12,153.80), Index of Agreement(IA) (0.55), and the coefficient of determination (R2) value for runoff (0.93). RMSE, IA, and R2 of 5.00, 0.95, and 0.83, respectively, were calculated for sediment yield.Over prediction by the model as evident in larger RMSE values may be attributed to complex varying environmental factors of the catchment that may not be accounted for by the model. Overall, GeoWEPP performed satisfactorily implying applicability in the catchment with intensive cultivation and steeper hillslopes.
Keywords: DEM, GeoWEPP, GIS, runoff, sediment yield
This study determined the soil carbon sequestration potential of major agricultural land use types in Bukidnon, Philippines which included plantations for corn, rice, sugarcane, pineapple, banana, rubber, cassava, coconut, coffee, and mango. Field measurement of soil organic carbon (SOC) stock was adopted with modification using the sampling protocol described by Hairiah, Sitompul, Van Noordwijk, and Palm (2001). Among the ten land use types examined, rubber and coconut plantations showed significantly the highest soil organic carbon sequestered amounting to 37.1 MgC ha-1 and 30.3 MgC ha-1, respectively while pineapple plantation had the least at 14.7 MgC ha-1. Although theoretically, SOC decreases with soil depth, there is no significant variation among soil depths at 10 cm, 20 cm, and 30 cm in terms of their ability to store organic carbon in this study. These findings need to be communicated to policymakers to institutionalize interventions that are necessary to keep or increase further the existing carbon stocks in these agricultural land areas.
Keywords: climate change, SOC, agricultural plantations, Bukidnon
Central Mindanao University Journal of Science