Presentation on theme: "MENANAM POHON UNTUK MEMANEN AIR HUJAN Soemarno - psdl ppsub 2013."— Presentation transcript:
MENANAM POHON UNTUK MEMANEN AIR HUJAN Soemarno - psdl ppsub 2013
MENANAM POHON UNTUK MEMANEN AIR HUJAN Kombinasi teras bangku dan vegetasi pohon untuk memaksimumkan hasil panen air hujan
Sumber: Siklus air hujan mengisyaratkan besarnya peluang untuk memanen air hujan
Karakter pohon dapat dimanfaatkan untuk memanen air hujan dan energi matahari sebanyak-banyaknya
SIKLUS HIDROLOGI Diunduh dari sumber: ….. 31/10/2012 The hydrologic cycle over land includes interception of precipitation by plant foliage and wood, throughfall and stemflow, transpiration, soil evaporation, canopy evaporation, infiltration, runoff, soil water, aquifer recharge, and snow. These are directly linked to the biogeophysics and also affect temperature, precipitation, and runoff.
EVAPOTRANSPIRASI The total evapotranspiration (ET) can be broken down into the Tr is transpiration, Ei interception evaporation, and Es evaporation from the bare soil and forest floor litter. On an annual basis in a forested environment, transpiration is the dominant component of ET, followed by interception evaporation and then bare-soil evaporation. However, during precipitation events, interception evaporation becomes the dominant component of ET during rainfall and during the hours immediately following precipitation. Diunduh dari sumber: transient-characteristics-of-the-hydrological-balance…..31/10/2012
INTERSEPSI Diunduh dari sumber: 3110/2012 Interception refers to precipitation that does not reach the soil, but is instead intercepted by the leaves and branches of plants and the forest floor. It occurs in the canopy (i.e. canopy interception), and in the forest floor or litter layer (i.e. forest floor interception. Because of evaporation, interception of liquid water generally leads to loss of that precipitation for the drainage basin, except for cases such as fog interception.
Akar Pohon Diunduh dari sumber: ….. 31/10/2012 Tree species are not necessarily "deep-rooted" or "shallow- rooted" -- certain species are more or less sensitive to various levels of moisture, oxygen, and minerals. Often roots will "bounce" off a soil hardpan or a high water table, forming surface roots where other species may not be able to live at all.
Provide social, ecological, and economic benefits Their leaves and roots clean the air we breathe and the water we drink Trees: The Original Multi-taskers Their beauty inspires writers and other artists.
Save Energy; Improve air quality Extend life of paved surfaces Increase traffic safety Increase real estate values Increase sociological benefits Protect our water resources Benefits of Trees in Urban Areas
11 All water is part of this cycle
Storm Water dan Siklus Hidrologi Urbanization dramatically alters the hydrologic cycle –Increases runoff –Increases flooding frequency –Decreases infiltration and groundwater recharge Nationwide impervious surfaces have increased by 20% in the past 20 years
14 More Trees Means Less Runoff Some Statistics Fayetteville, Arkansas: increasing tree canopy from 27-40% reduced their storm water runoff by 31% South Miami residential study found that a 21% existing tree canopy reduces the storm water runoff by 15% For every 5% of tree cover added to a community, storm water is reduced by approximately 2%
Bagaimana pohon mengendalikan “Stormwater”? Above ground effects: –Interception, evaporation and absorption of precipitation Ground surface effects: Temporary storage Below ground effects: Infiltration, permeation and filtration
Infiltrasi dan perkolasi air-hujan dalam tanah merupakan dua proses hidrologis yang sangat diperbaiki oleh adanya vegetasi pohon
EFEK POHON TERHADAP LINGKUNGAN DI ATAS TANAH Intercept rainwater on leaves, branches and trunks – slowing its movement Evaporation of some of this intercepted precipitation of the tree surfaces Absorption of a small portion into leaves or stems
Leaf litter and other organic matter can hold precipitation and stemflow on a site, reducing the amount and peak rates of runoff Efek Pohon terhadap Lingkungan Bawah Tanah Roots and trunk bases of mature trees tend to create hollows and hummocks on the ground
Organic material from leaf litter and other tree detritus tends to increase infiltration rates by increasing pore spaces in soil Organic material also increases the moisture-holding capacity of these sites Root mats of trees also tend to break up most soils further improving infiltration and moisture-holding capacity Efek Pohon terhadap Lingkungan Bawah Tanah
EFEK LINGKUNGAN-BAWAH-TANAH Deep roots tend to improve the rates of percolation of water from upper soil horizons into lower substrates Trees take up water through their roots that is eventually transpired onto leaf surfaces and evaporated Tree roots act as natural pollution filters (biofilters) using nitrogen, phosphorus and potassium
TAJUK POHON - KENYAMANAN Set to protect a community’s green infrastructure and maximize the environmental benefits For metropolitan areas east of the Mississippi –Average tree cover for all land use 40% –Suburban residential 50% –Urban residential 25% –Central business districts 15%
MULTIPURPOSES …? Ruang terbuka hijau – Taman pohon buah- buahan
COMPLICATING FACTORS Presence of soil compaction Presence of soil textural discontinuity –Has the site been disturbed in the past? Management of the ground surface –Is litter layer removed? –Is soil surface exposed in winter? –How much of the surface is like a natural forest? (number and size of trees)
PERGERAKAN LENGAS TANAH Forces affecting the energy of soil water –Matric force (absorption and capillary) –Gravity –Osmotic forces Field Capacity is the amount of water held in the soil after gravitational water had drained away Movement of water is the soil is controlled : –Gravitational forces if saturated –Matric forces if unsaturated
Tanah mempengaruhi Infiltrasi air hujan Infiltration is the mode of entry of all water into the soil Rate of infiltration determined: –Initial water content –Surface permeability –Internal characteristics of the soil Intensity and duration of rainfall Temperature of soil and water
Tanah mempengaruhi Infiltrasi Microrelief under trees provides catchment basins during heavy rains Removal of litter layer reduces the infiltration rate Forest soils have a high percentage of macropores The frost type found in forest soils promotes infiltration year-long Soil compaction reduces the infiltration rate
PENTINGNYA SERESAH DI PERMUKAAN TANAH 1.Absorbs several times its own weight 2.Breaks the impact of raindrops 3.Prevents agitation of the mineral soil 4.Discourages formation of surface crusts 5.Increases soil biotic activity 6.Increases incorporation of organics 7.Slows down lateral movement of water
POROSITAS TANAH Develop in old root channels or from burrows and tunnels made by insects, worms or other animals Lead to better soil structure Increases organic matter incorporation Increases percolation rates and root penetration
TANAH DI BAWAH TEGAKAN HUTAN Granular –Found in woodland soils with litter –May be more permeable Honeycomb –Has loose porous structure –Found in highly aggregated soils and also formed in organic layers and litter layers
AIR-TANAH-TANAMAN The proportion of the soil occupied by water and air is referred to as the pore volume. The pore volume is generally constant for a given soil layer but may be altered by tillage and compaction. The ratio of air to water stored in the pores changes as water is added to or lost from the soil. Water is added by rainfall or irrigation. Water is lost through surface runoff, evaporation (direct loss from the soil to the atmosphere), transpiration (losses from plant tissue), and either percolation (seepage into lower layers) or drainage.