This study had developed a raster-based tool in order to automate the soil erosion vulnerability assessment. The tool that designed based on the empirical USLE (Wischmeier and Smith, 1978) was built using various available GIS geoprocessing tools. The data used in this study were prepared using Erdas Imagine and ArcGIS softwares. The cluster Municipalities of Real, Infanta and General Nakar (REINA), Quezon, Philippines were selected as study area as it was previously hit by strong typhoon that led to severe landslide and deluge in 2004. Damages to lives and properties were remarkably the biggest in the history of these Municipalities. Using the raster-based tool, erosion vulnerability was assessed. The results were categorized into six (6) classes. It showed that None to slight covers 33.42% of the total area while Very severe ranked second with 23.83%. Other categories were Moderate with (2.26%), High (14.05%), Very high (18.80%) and Severe (7.63%) respectively. Higher percentage of None to slight can be justified by the fact that the area is still having 47% dense vegetation. However, high percentage of Very severe was attributed to presence of hundreds of bare/eroded areas in the mountain created by landslide due to heavy rain during a disaster in 2004. The developed tool is believed to be useful in the current situation wherein the country is on the process of nationwide hazard mapping.

Selection of native tree species for commercial purposes is a continuing challenge and an opportunity in tropical silviculture. Because of this, we explored domesticating 33 native species in the Philippines that were tested for survival rate, total height, and diameter-at-ground-level (dgl) increments. The first five years (2014–2018) of assessment showed that 13 species (40%) of the 33 native species reached a survival rate of more than 80%. Grouped as ‘slow’-, ‘medium’- and ‘fast’-growing field trial species, a 709 cm average total height at five years was attained by the fast-growing cluster where Bagalunga (Melia dubia L.) and Kupang (Parkia javanica (D.C.) Merr.) were among the fastest-growing species. Slow-growing trees like Tindalo (Afzelia rhomboidei (Blanco)) and Kamagong (Diospyros blancoi (Willd)) were among the slowest-growing with an average height of 193.8 cm. Dipterocarps like Yakal (Shorea stylosa (Foxw.)), Tanguile (Shorea polysperma (Blanco)) and Mayapis (Shorea squamata (Blanco) Merr.) had the lowest diameter at ground level (dgl) increments (average 25.9 mm) while diametric expansion of fast-growing species spanned up to 93.5 mm. Overall, height and dgl increments were almost five times the original measurement five years after planting. A sudden surge in the rate of change in total height (83%) and dgl (72%) occurred a year after planting, yet a sudden decline occurred in the fifth year with only 21% for height and 23% for diameter growth suggesting the first 3–4 years as the crucial stage in seedling development. Survival rate is better correlated with the changes in dgl increment (R2 = 0.19, p < 0.05) than the height growth (R2 = 0.12, p < 0.05). Increasing rainfall and optimum air temperature significantly correlated with height and diameter growth while any increase in recorded wind speed slightly reduced the growth of the species. Our findings are initial steps towards developing appropriate silvicultural and management interventions when planning for the massive plantation development of domesticated Philippine native trees in the future.

This study has developed soil fertility map and determined crop suitability in the province of Bukidnon, Mindanao Philippines using GIS. It entails combining and analyzing agro-environmental, soil information and crops biological requirements for growth.Result of analyzed soil samples revealed that light clay soils dominated the province. Combining these results with the determined soil chemical properties showed that the province is of high soil fertility in 300-500 masl, medium fertility in 501-900 masl and medium to high fertility in 901-1500 masl part of the province. GIS analysis also showed that 44.87% of the total area of the province was suitable for farming purposes given their slope and geologic characteristic. Overlaying the generated agro-climatic map with land suitable for farming practice map and soil fertility map, a crop suitability map has been developed. Matching crops biological requirements for growth to the crop suitability map was able to identify the specific crops applicable in certain part of the province. Among the recommended crops are rice, sugarcane, corn, coconut and cassava which were found out to be suited in lower areas with high temperature, highly suitable for farming due to low slope condition and high soil fertility. Pineapple, mango and banana on the other hand were suited in above-said areas including those up to 900 masl due to their capability to survive in high and relatively low temperature but of medium soil fertility. Tomato and potato however were suited in higher areas where temperature is cool and medium to high soil fertility. GIS analysis showed that there were areas in the province that are still high potential and suitable for farming purposes given the parameters used.

The main objective of this study was to develop a geo-spatial information system a combining web, Geographic Information System (GIS) and remote sensing technologies. This paper introduces an integrated web-based GIS and remote sensing architecture with three levels of geographic information services called Spatial Information System (SIS). The combinations of Java, Java applets, HTML, ASP.Net, VB Script, Java Script, SQL and web server components were utilized to develop the SIS. The prototype SIS was developed to provide an easy access to the geospatial information. Multi-temporal satellite images in Nuwaraeliya, Sri Lanka, were used for the evaluation. The SIS provides many facilities on web-based image analysis and land use/cover change detection for environmental resource management. The analyzed results of the temporal land use/ cover and the vegetation cover change were presented through the web-system. Areas vulnerable to soil erosion were identified using the raster-based USLE (Universal Soil Loss Equation) tool created inside GIS environment. The web-based GIS and remote sensing tools were considered to be significantly useful for accessing geospatial data without using expensive image processing applications. The study area of this research was selected as an example and the system demonstrates the way of distributing the derived satellite images through the online with some processing tools. Therefore, this application can be used as an example on future research.

Although tropical peatlands are huge carbon reservoirs, they are threatened by climate change and anthropogenic disturbances. Here, we assessed two contrasting peatland sites in the Philippines in terms of aboveground biomass and carbon content, soil carbon stock, and CO2 fluxes in the soils. The Caimpugan peatland in Agusan del Sur was considered the ‘undisturbed’ site, while the Bambanin peatland in Mindoro Oriental was the ‘disturbed’ site. The aboveground biomass at the undisturbed site was 35.8 ± 30.0 Mg ha−1) while at the disturbed site, it was 2.0 Mg ha−1 ± 1.9 Mg ha−1. The aboveground C content at the undisturbed site varied from 1.29 Mg C ha−1 to 37.2 C Mg ha−1, while the disturbed site only ranged from 0.1 Mg C ha−1 to 2.1 Mg C ha−1. A trend of increasing soil carbon content as the soil gets deeper was observed in both sites. At the undisturbed site, the average soil carbon content was 750 ± 710 Mg ha−1 and 595 ± 406 Mg ha−1 at the disturbed site. In terms of soil carbon emission, the undisturbed site had 3.6 ± 3.0 g C m−2d−1 and was only one-third the emission rate at the disturbed site (11.2 ± 6.4 g C m−2d−1). Our study highlights the dire condition of a disturbed peatland in terms of vegetation/soil carbon dynamics. We underscored the need to address the pressing issues on peatland drainage, agricultural activities, and human settlement within the peatland sites geared towards effectively managing this important carbon reservoir in the Philippines.