Presentation on theme: "MENANAM POHON UNTUK MENABUNG AIR-HUJAN Diabstraksikan: smno.psdl.ppsub.2013."— Presentation transcript:
MENANAM POHON UNTUK MENABUNG AIR-HUJAN Diabstraksikan: smno.psdl.ppsub.2013
Diunduh dari:. Pohon ialah tumbuhan dengan batang dan cabang yang berkayu. Pohon memiliki batang utama yang tumbuh tegak, menopang tajuk pohon. Pohon dibedakan dari semak melalui penampilannya. Semak juga memiliki batang berkayu, tetapi tidak tumbuh tegak. Dengan demikian, pisang bukanlah pohon sejati karena tidak memiliki batang sejati yang berkayu. Jenis-jenis mawar hias lebih tepat disebut semak daripada pohon karena batangnya walaupun berkayu tidak berdiri tegak dan habitusnya cenderung menyebar menutup permukaan tanah.
Diunduh dari: www.thecottagekey.com/watershed.htm POHON adalah tumbuhan berkayu yang perennial. Kadangkala pohon didefinisikan sebagai tanaman berkayu yang mencapai diameter 10 cm (lingkaran batangnya 30 cm) atau lebih besar pada ketinggian nafas manusia (130 cm di atas permuakan tanah). Ada kesepakatan ukuran minimum, istilah yang biasanya digunakan bagi tanaman yang tumbuh tingginya minimal 5-6 meter (15-20 ft) pada saat ia dewasa dan mempunyai percabangan sekunder yang bertumpu pada batang utama, yang disebut “a trunk”. Kebanyakan pohon menunjukkan dominasi pucuk yang jelas, meskipun tidak selalu demikian. Kalau dibandingkan dengan tumbuhan lainnya, pohon umurnya lebih panjang, ada yang mencapai beberapa ratus tahun dan tingginya mencapai 115 meter (375 ft).
Peran pohon dalam siklus air POHON merupakan komponen penting dari bentang-lahan alami karena kemampuannya untuk mencegah erosi dan menyediakan ekosistem khas di dalam dan di bawah naungan tajuknya. Poon juga mempunyai peranan penting dalam menghasilkan oksigen dan mereduksi CO2 di atmosfir, juga mampu memoderasi suhu permukaan bumi. Pohon juga merupakan komponen penting dari bentang-lahan dan pertanian, karena wujud estetikanya atau karena produksi buahnya (misalny apel). Kayu dari pohon menjadi bahan bangunan yang penting.
1.Save Energy 2.Improve air quality 3.Extend life of paved surfaces 4.Increase traffic safety 5.Increase real estate values 6.Increase sociological benefits 7.Protect our water resources Benefits of Trees in Urban Areas Pepohonan membersihkan udara yang kita hirup. Partikel debu, CO, SO2, dan polutan- polutan lain akan diserap oleh tanaman sehingga kita bisa menghirup udara yang lebih baik kualitasnya.
All water is part of this cycle Pepohonan Meningkatkan kualitas air tanah. Pepohonan mengurangi aliran permukaan (run-off), karena akarnya menyerap air yang jatuh ke tanah. Lebih banyak air yang terserap ke dalam tanah artinya lebih banyak kesempatan untuk memperbaiki kualitas dan kuantitas air tanah. Hal ini juga mengurangi tercemarnya air tanah oleh bahan kimia yang ada di permukaan tanah.
AIR HUJAN DAN SIKLUS HIODROLOGI 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
More Trees Means Less Runoff Some Statistics 1.Fayetteville, Arkansas: increasing tree canopy from 27-40% reduced their storm water runoff by 31% 2.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% Arkansas stormwater runoff reduction valued at $43 million in capital improvement savings (represents $2/ cubic ft cast to contain storm water runoff).
BAGAIMANA POHON MEMPENGARUHI AIR HUJAN? Above ground effects: –Interception, evaporation and absorption of precipitation Ground surface effects: –Temporary storage Below ground effects: –Infiltration, permeation and filtration
EFEK POHON PADA LINGKUNGAN MIKRO DI ATAS TANAH Intercept rainwater on leaves, branches and trunks – slowing its movement Evaporation of some of this intercepted precipitation of the tree surfaces 1.The delay of precipitation onto the ground can dampen the peak of runoff amounts from storms which are most intense at their outset, before the storage capacity of the tree canopy is reached. 2.The amounts of the effects on runoff are primarily dependent on season (for deciduous trees), on the leaf area index of a tree and on its density of twigs and branches. 3.The evaporation rate is also crucial in influencing the above-ground effects. This rate is determined by air temperature, humidity and the intensity of solar radiation. With a large amount of leaf-surface area exposed to the sun and wind, water loss from the leaves is high. 4.By slowing the storm water flow, the flow of water is spread over a greater amount of time (time of concentration) and the impact of a storm on the facilities built to handle it at any one time is smaller. 5.Stemflow is a relatively small percentage of total precipitation 6.Absorption of a small portion of rainwater into leaves or stems
13 EFEK POHOIN TERHADAP LINGKUNGAN BAWAH TANAH 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
14 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 EFEK POHOIN TERHADAP LINGKUNGAN BAWAH TANAH
EPA’s Tree Canopy Target Goals 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%
FAKTOR KOMPLIKASI 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 AIR DALAM 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
FAKTOR TANAH MEMPENGARUHI INFILTRASI 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
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 FOTO SMNO 2008 FAKTOR TANAH MEMPENGARUHI INFILTRASI
PENTINGNYA LAPISAN SERESAH DI PERMUKAAN TANAH Absorbs several times its own weight Breaks the impact of raindrops Prevents agitation of the mineral soil Discourages formation of surface crusts Increases soil biotic activity Increases incorporation of organics Slows down lateral movement of water The litter layer absorbs several times its own weight of water, breaks the impact of raindrops, prevents agitation of the mineral soil particles and discourages the formations of surface crusts. It also leads to an increase in the organic matter content of the top mineral layer and creates a habitat for many of the soil fauna to feed and hide in which in turn increases the porosity of the soil. The variety, numbers and activity of soil organisms generally is much greater in forest soils than in agricultural soils or in lawns. It also slows down the lateral movement of surface water permitting a longer period for infiltration.
Mempengaruhi pori-mikro dalam tanah the Soil 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
Diunduh dari: http://repository.unib.ac.id/42/. Suharto, Edi (2006) THE CAPACITY OF SOILWATER STORAGE ON LAND USE SYSTEM AT LPP TAHURA RAJA LELO BENGKULU. JIPI, 8 (1). pp. 44-49. ISSN 1411-0067 Objective of this study was to measure soil water storage capacity on land use system at LPP TAHURA Raja Lelo Bengkulu. Research was conducted from September 1999 to February 2000 in Laboratory of soil of Agriculture Department, Gadjah Mada University. The Research used sampling design and analysis the physics and chemistry of soils. Land use system was covered by tree crops which high of water storage capacity of soils. Those covered by grasses and scrub will be less. The variable of water storage capacity of soils are rain fall interception by vegetation of land cover, soil depth of root interception, the balanced of soil particle distribution of clays and sands, and the distribution of soil micro pore. Soil water drainage was determined by amount of organic matter in top soils. Therefore, forest and estate land use system covered by tree crops is an effective conventional landscape for soil and water conservation.
Source and fate of water added to a soil system. 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.
PENGGUNAAN AIR TANAH DAN PENGISIANNYA DARI PERMUKAAN There is a substantial amount of ground water recharge from surface water and ground water used to irrigate agricultural crops. Some of the irrigation water flowing in unlined ditches and some of the water that is applied to irrigate crops infiltrates into the soil, percolates through the root zone and recharges the ground water basins
AIR TANAH = Ground water Ground water occupies the zone of saturation. Ground water moves downward through the soil by percolation and then toward a stream channel or large body of water as seepage. The water table separates the zone of saturation from the zone of aeration. The water table fluctuates with moisture conditions, during wet times the water table will rise as more pore spaces are occupied with water. Ground water is found in aquifers, bodies of earth material that have the ability to hold and transmit water. Aquifers can be either unconfined or confined. Unconfined (open) aquifers are "connected" to the surface above.
AQUIFERS REPLENISH THEIR SUPPLY OF WATER VERY SLOWLY. The rate of ground water flow depends on the permeability of the aquifer and the hydraulic gradient. Permeability is affected by the size and connectivity of pore spaces. Larger, better connected pore spaces creates highly permeable earth material. The hydraulic gradient is the difference in elevation between two points on the water table divided by the horizontal distance between them. The rate of ground water flow is expressed by the equation: Ground water flow rate = permeability X hydraulic gradient Groundwater flow rates are usually quite slow. Average ground water flow rate of 15 m per day is common. Highly permeable materials like gravels can have flow velocities of 125 m per day.
Ground water in an aquifer is under pressure called hydrostatic pressure. Hydrostatic pressure in a confined aquifer pushes water upward when a well is drilled into the aquifer. The height to which the water rises is called the peizometeric surface. If the hydrostatic pressure is great enough to push the peizometeric surface above the elevation of the surface, water readily flows out as an artesian well. DIUNDUH DARI: www.uwsp.edu/geo/faculty/ritter/geog101/textb...
Following an infiltration event, in which the entire soil profile becomes saturated with water (indicated by a solid vertical line corresponding to a water saturation of 1.0), water will drain from the soil profile primarily under the influence of gravity (i.e., the pressure gradient is negligible). Assuming that no additional water enters the system, the soil water saturation profile at static equilibrium (dashed line) will decrease from a value of 1.0 in the saturated zone (groundwater and capillary fringe) to a value corresponding to field capacity below the root zone. In effect, the soil water profile is analogous to a soil water retention (pressure-saturation) curve. Hence, the solid and dashed lines represent the limits in water content (saturation) between which soil water percolation occurs in soils overlying an unconfined aquifer. www.informaworld.com/smpp/95829679-70617050/c...
KONDISI ALAMIAH PENGISIAN AIR TANAH Water is recharged to the ground-water system by percolation of water from precipitation and then flows to the stream through the ground-water system. DIUNDUH DARI: ga.water.usgs.gov/edu/earthgwdecline.html
30 PENURUNAN TINGGI MUKA AIR TANAH Water pumped from the ground-water system causes the water table to lower and alters the direction of ground-water movement. Some water that flowed to the stream no longer does so and some water may be drawn in from the stream into the ground-water system, thereby reducing the amount of streamflow..
KUALITAS AIR TANAH Contaminants introduced at the land surface may infiltrate to the water table and flow towards a point of discharge, either the well or the stream. (Not shown, but also important, is the potential movement of contaminants from the stream into the ground-water system.)
EFEK AIR TANAH TERHADAP LINGKUNGAN Water-level declines may affect the environment for plants and animals. For example, plants in the riparian zone that grew because of the close proximity of the water table to the land surface may not survive as the depth to water increases. The environment for fish and other aquatic species also may be altered as the stream level drops.
34 Forests and the Hydrologic Cycle The surface water in a stream, lake, or wetland is most commonly precipitation that has run off the land or flowed through topsoils to subsequently enter the waterbody. If a surficial aquifer is present and hydraulically connected to a surface-water body, the aquifer can sustain surface flow by releasing water to it. In general, a heavy rainfall causes a temporary and relatively rapid increase in streamflow due to surface runoff. This increased flow is followed by a relatively slow decline back to baseflow, which is the amount of streamflow derived largely or entirely from groundwater. During long dry spells, streams with a baseflow component will keep flowing, whereas streams relying totally on precipitation will cease flowing. Generally speaking, a natural, expansive forest environment can enhance and sustain relationships in the water cycle because there are less human modifications to interfere with its components. A forested watershed helps moderate storm flows by increasing infiltration and reducing overland runoff. Further, a forest helps sustain streamflow by reducing evaporation (e.g., owing to slightly lower temperatures in shaded areas). Forests can help increase recharge to aquifers by allowing more precipitation to infiltrate the soil, as opposed to rapidly running off the land to a downslope area.
POHON DAN AIR HUJAN Trees have a relatively greater effect on smaller storm runoff amounts than on large storm events Surface and below-ground effects on runoff are much more significant than the above-ground effects All of the effects on runoff are greatest when urban trees are large and well-established on undisturbed sites
DIUNDUH DARI: www.aucklandcity.govt.nz/.../hgiapp15.asp Typical root systems are made up of a combination of four types of roots: major lateral roots sinker roots woody feeder roots non-woody feeder roots.
Diunduh dari:. Menanam Pohon di Lahan Datar Lahan yang datar yang umumnya ditanami biji-bijian, sayuran, dan padi dapat dikombinasikan dengan berbagai macam tanaman pohon. Tanaman pohon akan meningkatkan jumlah produksi dan keragaman tanaman. Tanaman pohon sedikit memerlukan perawatan dan akan tetap bermanfaat walaupun di musim kemarau. Tanaman pepohonan kecil seperti jeruk, pisang, pepaya, cengkeh, dan kacang hijau dapat ditanam bersama dengan tanaman biji-bijian dan sayuran. Pohon dapat memberikan naungan untuk tanaman musiman yang lebih kecil. Pohon juga akan memberikan penghalang untuk mempersulit gerak hama serangga saat berpindah dari tanaman satu ke tanaman lainnya. Tanam pula legum, tanaman ini memiliki manfaat yang sangat banyak. Manfaat lain dari kombinasi pohon dengan tanaman biji-bijian dan sayuran adalah tanaman kecil bisa dipanen lebih awal sementara menunggu pohon yang besar tumbuh dan menghasilkan.
Diunduh dari: http://ieeexplore.ieee.org/xpl/articleDetails.jsp?reload=true&arnumber=6058457&con tentType=Conference+Publications. EFFECT OF ORGANIC AMENDMENTS ON SOIL WATER STORAGE IN THE AEOLIAN SANDY LAND OF NORTHEAST CHINA Wenju Liang Wenju Liang, Xia Wu ; Shixiu Zhang ; Yuehua Xing ; Ren WangXia Wu Shixiu Zhang Yuehua Xing Electrical and Control Engineering (ICECE), 2011 International Conference on. Date of Conference: 16-18 Sept. 2011 Organic amendments such as crop residues and animal manures play an important role in improving soil quality. The objective of this research was to determine the effect of corn straw retention and chicken manure on soil water storage in the aeolian sandy land of Northwest Liaoning province, China. After four-year observation, the results showed that corn straw in combination with chemical fertilizer (SR) treatment significantly increased soil water content in the plow layer, decreased soil bulk density in the plow pan, and obviously enhanced plant available water storage capacity in the plow pan. The chicken manure in combination with chemical fertilizer (CM) treatment significantly increased soil water content and organic matter content in the plow layer. Our experiment indicates that corn straw retention combined with chemical fertilizers may improve soil water storage capacity in the short-term study.
Diunduh dari: http://www.hydrol-earth-syst-sci.net/1/265/1997/hess-1-265- 1997.html. Soil water storage and groundwater behaviour in a catenary sequence beneath forest in central Amazonia: I. Comparisons between plateau, slope and valley floor M. G. Hodnett 1, I. Vendrame 2, A. De O. Marques Filho 3, M. D. Oyama 4, and J. Tomasella Hydrol. Earth Syst. Sci., 1, 265-277, 1997 Soil water storage was monitored in three landscape elements in the forest (plateau, slope and valley floor) over a 3 year period to identify differences in sub-surface hydrological response. Under the plateau and slope, the changes of storage were very similar and there was no indication of surface runoff on the slope. The mean maximum seasonal storage change was 156 mm in the 2 m profile but it was clear that, in the dry season, the forest was able to take up water from below 3.6 m. Soil water availability was low. Soil water storage changes in the valley were dominated by the behaviour of a shallow water table which, in normal years, varied between 0.1 m below the surface at the end of the wet season and 0.8 m at the end of the dry season. Soil water storage changes were small because root uptake was largely replenished by groundwater flow towards the stream. The groundwater behaviour is controlled mainly by the deep drainage from beneath the plateau and slope areas. The groundwater gradient beneath the slope indicated that recharge beneath the plateau and slope commences only after the soil water deficits from the previous dry season have been replenished. Following a wet season with little recharge, the water table fell, ceasing to influence the valley soil water storage, and the stream dried up. The plateau and slope, a zone of very high porosity between 0.4 and 1.1 m, underlain by a less conductive layer, is a probable route for interflow during, and for a few hours after, heavy and prolonged rainfall.
Diunduh dari: http://hortsci.ashspublications.org/content/32/6/1059.abstract. STEM FLOW, THROUGHFALL, AND CANOPY INTERCEPTION OF RAINFALL BY CITRUS TREE CANOPIES Y.C. Li, A.K. Alva, D.V. Calvert and M. Zhang. HortScience October 1997 vol. 32 no. 6 1059-1160 It is generally believed that the interception of rain by the citrus tree canopy can substantially decrease the throughfall under the canopy as compared to that along the dripline or outside the canopy (incident rainfall). Therefore, the position of placement of soil-applied agrichemicals in relation to the tree canopy may be an important consideration to minimize their leaching during rain events. In this study, the distributions of rainfall under the tree canopies of three citrus cultivars, `Marsh' grapefruit (Citrus paradisi Macf.), `Hamlin' orange (Citrus sinensis L. Osbeck), and `Temple' orange (Citrus hybrid), were evaluated at four directions (north, south, east, west), two positions (dripline and under the canopy), and stem flow. There was not a significant canopy effect on rainfall amounts from stem flow or dripline, compared with outside canopy, for any citrus cultivar or storm event. However, throughfall varied significantly among the four cardinal directions under the canopy of all three citrus cultivars and was highly related to the wind direction. Among the three citrus cultivars evaluated in this study, throughfall, stem flow, and canopy interception accounted for 89.5% to 92.7%, 0.5% to 4.7%, and 5.8% to 9.3% of the incident rainfall, respectively.
54 Four-Way Collaboration The Water Balance Model includes a tree canopy module so that the rainfall interception benefits of trees in the urban environment can be quantified. To populate the module with local data, a four-way collaboration has been established under the umbrella of the Inter- Governmental Partnership (IGP) that developed the Water Balance Model. The Greater Vancouver Regional District and Ministry of Community Services are providing funding, and the University of British Columbia and District of North Vancouver are making in-kind contributions in carrying out the applied research project. The District of North Vancouver is acting on behalf of the IGP in leading this on-the-ground initiative.Water Balance Model
AIR HUJAN LOLOS-TAJUK Tree canopy interception is the process of storing precipitation temporally in the canopy and releasing it slowly to the ground and back to the atmosphere. It is an important component of the water balance, easily accounting for up to 35% of gross annual precipitation. Removing trees will in general decrease interception and thus increase annual runoff and rainwater runoff. Vegetation also reduces rainfall intensity due to the temporal storage effect.
Diunduh dari: http://si- pddr.si.edu/jspui/bitstream/10088/12103/1/stri_Park_and_Cameron_2008.pdf. The influence of canopy traits on throughfall and stemflow in five tropical trees growing in a Panamanian plantation Andrew Park and Jessie Lee Cameron Forest Ecology and Management 255 (2008) 1915-1925 Tree canopies partition rainfall into temporary canopy storage, throughfall and stemflow. Knowledge of this partitioning process is needed to predict the hydrological effects of the large areas of tree plantations that are being established in the tropics. In this study, we compared throughfall, stemflow and interception in four Neotropical and one exotic tree species growing in selection trials in the Republic of Panama. We sought to answer four questions: (1) Are there interspecific differences in total throughfall and stemflow, and throughfall and stemflow for a range of rainfall depths?, (2) How do crown traits influence interspecific differences in throughfall?, (3) Does the spatial heterogeneity of throughfall differ among species? and (4) How do species affect litter biomass and other variables that influence rainfall erosivity? Rainfall depth mediated interspecific differences in throughfall and stemflow, the relative importance of crown traits in the interception process, and spatial heterogeneity of throughfall. Total throughfall was between 10.9 and 16.2% less in Acacia mangium than Gliricidia sepium, Guazuma ulmifolia, Ochroma pyramidale or Pachira quinata. Increasing rainfall also changed relative quantities of throughfall and stemflow among species. For example, throughfall was similar in Gliricidia and Acacia for small rain events, but increased more rapidly in Gliricidia with increasing rainfall depth. Interspecific differences in throughfall were driven, in part, by canopy traits. Leaf area index (LAI), crown depth and crown openness all affected throughfall from smaller storms, but live crown length was the only significant predictor of throughfall in storms that were deeper than 20 mm. The spatial heterogeneity of throughfall beneath individual tree canopies increased with rainfall depth, but was always lower in Gliricidia than in Acacia, Ochroma, or Pachira. High litter biomass and cover in Acacia and Ochroma relative to other species would be likely to buffer the erosive effects of raindrop impacts. These complex interactions between rainfall and species traits may affect local hydrology, and may need to be explicitly considered in reforestation projects in the seasonal tropics.
Diunduh dari: http://treephys.oxfordjournals.org/content/21/12-13/1009.abstract. Interception loss, throughfall and stemflow chemistry in pine and oak forests in northeastern Mexico Israel Cantú Silva and Humberto González Rodríguez Tree Physiol (2001) 21 (12-13): 1009-1013. Interception loss, gross precipitation, throughfall and stemflow solution chemistry beneath pine (Pinus pseudostrobus Lindl.), oak (Quercus sp.) and pine–oak natural forest canopies in northeastern Mexico were measured. Coefficients of variation for throughfall were 12% in pine and oak canopies and 17% in the mixed pine–oak canopy. The variability of stemflow averaged 66, 126 and 73% for pine, oak and the mixed pine– oak canopies, respectively. Linear regression analysis of net versus gross precipitation for the three canopies showed highly significant correlations (r = 0.974–0.984). Total precipitation during the experimental period was 974 mm and estimated interception loss was 19.2, 13.6 and 23% for the pine, oak and pine–oak canopies, respectively. Stemflow did not occur following rainfall events of less than 4 mm and, in all canopies, stemflow represented a minimal proportion of gross precipitation (0.60, 0.50 and 0.03% for pine, oak and pine–oak, respectively). Throughfall pH in pine (6.2), oak (6.3) and pine–oak (6.3) canopies was significantly more acidic than gross precipitation (6.6). Stemflow pH ranged from 3.7 (pine) to 6.0 (oak). The pine–oak canopy registered the highest throughfall and stemflow electrical conductivities, 104 and 188 μS cm −1, respectively. Net nutrient leaching of K, Mg, Na, Fe, Mn and Zn was significantly higher from the pine–oak canopy than from the pure pine and oak canopies. Mean depositions of Ca and Cu in throughfall behaved similarly among the three types of canopies. A greater proportion of Zn in gross precipitation was absorbed by the oak canopy than by the pine and pine– oak canopies. Enrichment factors beneath the pine–oak canopy relative to gross precipitation varied from 1.2 to 3.2 for macro-nutrients (Ca, K, Mg and Na) and from 1.4 to 3.1 for micro-nutrients (Cu, Fe, Mn and Zn). Stemflow depositions of Ca, K, Mg and Cu were higher in the pine–oak canopy, whereas stemflow depositions of Na, Fe, Mn and Zn were higher in the pine canopy.
Diunduh dari: http://sciencelinks.jp/j- east/article/200524/000020052405A1013936.php. Spatial Distributions of Throughfall beneath Canopies of Understory Trees in a Mature Chamaecyparis obtusa Stand. TANAKA NOBUAKI, KURAJI KOICHIRO, SUZUKI MASAKAZU, OTA TAKEHIKO Bulletin of the Tokyo University Forests VOL. NO.113;PAGE.133-153(2005) Spatial distributions of throughfall beneath canopies of understory trees in a mature Chamaecyparis obtusa stand were observed by grid-type throughfall collectors. Throughfall amount beneath the canopies of understory trees tended to be smaller than that observed at grids covered only by canopy of Chamaecyparis obtusa. However, dripping points, where throughfall exceeded gross rainfall, often appeared under canopies of Aucuba japonica and Daphniphyllum macropodum, the species with relatively large leaves, and never appeared under canopies of Quercus myrsinifolia and Callicarpa mollis, the species with smaller leaves. With respect to frequency of appearances of dripping points, we found that the dripping points appeared more frequently in large storms than in small storms. However, no dripping point was found in two relatively large storms among nine observations, which seems to be exceptional. The pattern of the distributions of dripping point over a grid-type collector had a tendency to be fixed in most of the storms. The size of one dripping point found in this forest was a circular area with diameter of approximately 14cm. As an example of applying the result of this study to estimations of mean throughfall of this forest or its error ranges, a relationship between area of collecting throughfall and possible errors in measuring throughfall was shown by supposing to measure throughfall in the area of a grid-type collector with some virtual throughfall collectors.
Diunduh dari: http://repository.ias.ac.in/73033/. Loshali, D. C. ; Singh, R. P. (1992) PARTITIONING OF RAINFALL BY THREE CENTRAL HIMALAYAN FORESTS Forest Ecology and Management, 53 (1-4). pp. 99-105. ISSN 0378- 1127 Throughfall, interception losses and surface run-off studies during the monsoon season (June through September) in three different forests of Central Himalaya are described. The tree canopy covers of the stands were 80.0-91.5%. Canopy throughfall (throughfall directly beneath the canopy) made up 76.5% and canopy interception loss was 23.5% of the total rainfall (1965.8 mm) during the 1985 and 1986 monsoons. Values of throughfall and interception losses computed for entire forested stands (stand throughfall and stand interception) accounted for 79.6% and 20.2% of the total rainfall. The minimum canopy throughfall (74.9%) was recorded in chir pine and maximum (78.6%) in mixed banj oak-tilonj oak forest. Stand throughfall was maximum (80.7%) in mixed banj oak-chir pine forest and minimum (77.5%) in chir pine forest. Stand interception was higher in chir pine compared with mixed banj oak-chir pine and banj oak-tilonj oak forests. The highest value of surface run-off was recorded in chir pine forest which had the lowest litter interception (8.3%). Canopy throughfall and surface run-off were positively related (P < 0.01) to bulk precipitation. The low proportion of surface run-off (0.46-0.53%) is a characteristic and a special feature of the forest ecosystems of the Central Himalaya.
MENANAM POHON UNTUK MENABUNG AIR-HUJAN Diabstraksikan: smno.psdl.ppsub.2013