Assessing Impact of Land Use and Climate Changes on River Flow of Upper Citarum Watershed Rizaldi Boer Delon Martinus Ahmad Faqih Perdinan Bambang D. Dasanto

Study Site: Upper Citarum Covering an area of about 720 thousand ha There are three dams ~ vital for meeting water demand of about 11 districts within watershed and 5 districts outside the watershed (north coast of West Java) Cirata Dam Saguling Dam Jatiluhur Dam Upper Citarum

Monthly Average: Inflows to the three Dams in El- Nino, Normal and La-Nina years SAGULING CIRATA JATILUHUR/ H. JUANDA Inflow Local Inflows Sea level 87.5 m 107 m 206 m 220 m 625 m 643 m

Outflows from the three dams in normal and dry years SAGULING CIRATA JATILUHUR/ H. JUANDA outflow Inflow outflow Inflow Sea level 87.5 m 107 m 206 m 220 m 625 m 643 m outflow

Outflow and power generation

Vulnerability of Rice-Based Cropping System to Climate Variability

Average of Cumulative Drought Area between Normal and El-Nino years rice ~ 80% fallow rice fallow upland crops fallow vegetables fallow

Impact on Rice Production

Historical Land Use Changes Land Use Area (ha)Percent change ‘89‘93‘99‘ Bare land and shrub land Agriculture area 1/ Forest & vegetation covers 2/ Settlements Urban and Industries Dam/Lakes TOTAL

Change of Forest Cover in the Upper Citarum

Critical Land in Citarum Source: BP-DAS Citarum-Ciliwung (2003)

Community Perception About 85% of respondents stated that there is an increase in drought and flood frequency and intensity (Sulandari et al., 2004) Dialog between stakeholders and scientist at Bandung, it was suggested that at least 40% of watershed area should be maintained as conservation zone (forest cover) ~ It is believed that increasing forest cover will diminish the damage of flood and drought risk In 2010, government targeted to increase forest cover up to 48% of the total areas

Objectives To evaluate impact of land use and climate changes scenarios on river flow at Nanjung (Upper watershed) To develop recommendations for local government in setting up land use scenarios in the upper catchments of Citarum watershed

Step of Analysis Historical Land Use Observed Stream flow Historical Climate data VIC-BASIN Model Good? Develop relationship between % forest cover and base flow Select the base flow Change base flow and run off parameters Land Use Scenarios Climate Scenarios GCM Downscaled GCM to Study sites Estimate base flow parameter VIC-BASIN Model CLIMGEN Evaluate the impact and develop recommendation

Critical Land and Rehabilitation Plan for the Four Land Use Scenario for Upper Citarum Watershed

Land Use Scenarios 1989

Shrubs Dam/Lake Forest/Agroforest Agriculture City/Industrial Area Land Use Scenarios 17%: Baseline 19%: MIT-1 25%: MIT-2 29%: MIT-3 48%: RTRW

Relationship between base flow parameter and forest cover Citarum Sumber Jaya

Comparison between observed and Downscaled

Comparison between Observed (Above) and Downscaled Rainfall (Below) DJF MAMJJASON DJF MAMJJASON

Projected Annual Rainfall at Citarum Watershed Low Scenario High Scenario GCM outputs from ECHAM model downloaded from Data Distribution Centre

Result of Validation Using CLIMGEN

Distribution of stream flow under different land use and climate scenarios Baseline climate Low Scenario High Scenario Under baseline and low climate scenarios, increasing forest cover more than 20% and up to 47% of the total land areas would not change the distribution of stream flow Under high climate scenario, the distribution of stream flow under baseline and mitigation 1 land use scenario (percent land use cover is between 17% and 19%) was different from those under Mitigation 2 and 3 scenarios (percent forest cover is between 25% and 29%) and under RUTR (percent forest cover is 48%).

NEXT STEP Inflow and outflow analysis –Impact on electricity production –Risk of drought and flood –Drinking water availability during dry season Presenting the result in workshops and do policy dialogues Do more ground works with vulnerable groups

A SMALL STEP: INCREASING ADAPTIVE CAPACITY OF FARMERS TO EXTREME CLIMATE EVENTS THROUGH FIELD SCHOOL PROGRAM

Why we need Climate Field School? Climate fluctuates from time to time and also varies between locations Managing climate variability is not an easy task. Farmers are always suffering from drought whenever El-Nino occurs without able to anticipate the events. BMG who provides climate forecast information also could not effectively present their forecast Farmers also have difficulties to apply the climate information in the fields for practical uses

What is the concept of FS ? Get experiences Discuss/explain experiences to colleagues Analyze the experiences together with colleagues Make Decision Take action Field Facilitators

Objectives of CFS In the initial phase (short term):  To increase farmers knowledge on climate and ability to anticipate its phenomena such as extreme events for their farming activities base on their past experiences and current knowledge;  To assist farmers in observing climate phenomenon and using it to set up better planting strategies  To assist farmers how to translate climate forecast information for supporting their farming activities

Objectives of CFS Long term objective: To form farmer groups that have strong motivation to develop their own agribusiness activities where climate information is used as inputs for making better plans, strategies and decisions, and to protect the environment through their active participation in climate change mitigation programs

Communicating climate knowledge & climate information applications to increase adaptive capacity and community participations in mitigating climate change Research Agencies, Universities National and local Governments Farmers and other end users Transfer of knowledge & technology information through science and policy forum Inputs and Feed back Programs, policies, & regulations Inputs and Feed back Transfer of technologies through variety of means Sustainable system and prosperous communities Mitigation actions Adaptation actions NGOs Good incentive system Good climate forecasting system APPROACH