Mangrove plays a significant role in climate change mitigation particularly in carbon absorption and minimizing the detrimental impacts of sea level rise, saltwater intrusion and tidal surges. In Bohol Province, Philippines, a small coastal island community known as Banacon is one of the successful cases in mangrove reforestation. Recognizing the site's potential for a carbon sequestration project, a biomass and carbon stock assessment of mangrove trees was done. Using standard sampling techniques and allometric equations, tree carbon storage was measured across stand ages, namely 15-, 20-and 40-year-old plantations. Mature natural stands were also included in the assessment. By estimate, the 40-year-old plantation has the largest carbon density with 370.7 ton ha 71 , followed by the 15-year-old plantation with 208.5 ton ha 71 , 20-year-old plantation with 149.5 ton ha 71 , and lastly by natural stand with 145.6 ton ha 71. Overall, Banacon mangroves are in a vigorous condition of storing vast amount of carbon. Local community and government should therefore sustain their commitment in coastal reforestation activities in order to enhance the mangrove carbon stocks. Policies and programs that can help provide incentives and livelihoods to local people who are largely dependent on mangroves should likewise be explored in order to sustainably reap the economic and ecological benefits of conserving mangrove forest.

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A statistical downscaling known for producing station-scale climate information from GCM output was preferred to evaluate the impacts of climate change within the Mount Makiling forest watershed, Philippines. The lumped hydrologic BROOK90 model was utilized for the water balance assessment of climate change impacts based on two scenarios (A1B and A2) from CGCM3 experiment. The annual precipitation change was estimated to be 0.1-9.3% increase for A1B scenario, and −3.3 to 3.3% decrease/increase for the A2 scenario. Difference in the mean temperature between the present and the 2080s were predicted to be 0.6-2.2 • C and 0.6-3.0 • C under A1B and A2 scenarios, respectively. The water balance showed that 42% of precipitation is converted into evaporation, 48% into streamflow, and 10% into deep seepage loss. The impacts of climate change on water balance reflected dramatic fluctuations in hydrologic events leading to high evaporation losses, and decrease in streamflow, while groundwater flow appeared unaffected. A study on the changes in monthly water balance provided insights into the hydrologic changes within the forest watershed system which can be used in mitigating the effects of climate change.

Groundwater recharge and base flow using different investigated methods are simulated in the 15-ha Bukmoongol small-forested watershed located at the southern part of Korea. The WHAT system, PART, RORA, PULSE, BFI, and RAP software are used to estimate groundwater recharge or base flow and base flow index from the measured streamflow. Results show that about 15-31 per cent of annual rainfall might be contributed for base flow. The watershed groundwater recharge proportions are computed to about 10-21 per cent during the wet period and 23-32 per cent for the remainder periods. Mean annual base flow indices vary from 0.25 to 0.76 estimated using different methods. However, the study found out that all methods were significantly correlated with each other. The similarity of various methods is expressed as a weighted relationship provided by the matrix product from the principal component analysis. Overall, the BFI and WHAT software appeared consistent in estimating recharge or base flow, and base flow index under Korea's conditions. The case study recommends the application of different models to other watersheds as well as in low-lying areas where most observation groundwater wells are located with available streamflow data.