FRM 61 - Forest Biometry PDF

FRM 61 - Forest Biometry Study online at https://quizlet.com/_eb1q1z straight line passing through the center of a Diameter...

FRM 61 - Forest Biometry Study online at https://quizlet.com/_eb1q1z straight line passing through the center of a Diameter circle and meeting at each end of the circumference Reference diameter of standing trees Diameter at Breast Height is defined at 1.3 meters (4 feet 6 inches) above ground level may be measured outside bark (ob) and inside Diameter bark (ib) and the difference is twice the bark thickness 1. diameter above buttress (dab) 2. stump diameter Other Diameter measurements can 3. top diameter be done on: 4. intermediate diameter one of its sides is graduated at intervals of Àunits which allows direct reading of diameter, while the other side is graduated as an ordinary meter tape and can be used to measure circumfer- ence. Diameter Tape accurate only for trees that are circular in cross section its main parts are hook, tape, and tape reel or roller Meter Tape 1 / 12 FRM 61 - Forest Biometry Study online at https://quizlet.com/_eb1q1z The simplest instrument but Meter Stick usually prone to error Similar to ordinary tape measure with two (2) parallel arms where one arm is fixed at the origin of the scale and the Caliper other arm slides Particularly used in measuring diameter of logs This is not affected by weather or cli- mate. Aluminum Tree Caliper Measures diameters up to 8" in inches on one side (0 to 8" marked every 1/2") and centimeters on the other side (0 to 20 cm). 9-1/2" Long. Tree Fork Consists of a set of fixed arms Personalized instrument based Biltmore Stick on an individual's arm length Optical instrument which measures the diameter by two parallel lines of tree Wheeler Pentaprism Measure from any unobstructed sighting position and at any height on the tree-stump, dbh or merchantable height. An optical instrument used to measure tree diameters Relascope Wide Scale is designed for metric measurements (diameter measure- 2 / 12 FRM 61 - Forest Biometry Study online at https://quizlet.com/_eb1q1z ments convert to inches or centimeters). Recommended for trees larger than 244 cm (96 ) dbh. Measure growth and water status of Manual Band Dendrometer trees daily and seasonally Quick diameter measurements up to 40 Bitterlich Treemeter inches Consecutive front and back graduations allow you to determine both the circum- Pole Tape ference and diameter of poles/pole tim- ber. Straight tree without buttresses or Flat Terrain with buttress less than 1m or with aerial roots less than 1m The diameter measurement of Sloping Terrain the vertical tree is taken at 1.30m at the uphill side. The 1.30 m length has to be measured parallel to the tree, not vertically. The Leaning Trees measured section has to be perpendic- ular to the axis of the tree, not horizontal. It is the vertical distance from the base to the tip of the tree Total Height the distance along the axis of the tree stem between the ground and the tip of the tree Total Height Bole Height Height Classes Merchantable Height Stump Height is the distance along the axis of the tree Bole Height between the ground and the crown point 3 / 12 FRM 61 - Forest Biometry Study online at https://quizlet.com/_eb1q1z is the distance along the axis of the tree Merchantable Height from the stump to the terminal position of the last usable portion of the tree stem is the distance between the ground and the basal position on the main stem Stump Height where a tree is cut. This is usually 0.5m above the ground Consists of a graduated arc mounted on a sighting tube Abney Hand Level The arc has a degree, percentage or topographic scale For quick determination of tree height. To use this in measuring tree height, follow the steps below: Sight the top of tree and while keeping the level bubble centered Tangent Height Gauge Measure the distance from you to the base of the tree = D Measure your height to your eye level = H Add D and H to get the height of the tree =D+H a gravity-controlled pivoted pointer with a series of scales (15, 20, 25 and 30), Haga Altimeter chains (66 L) and a percent scale Direct reading of height accurately measures tree heights by obtaining the elevation angle between you and the measured points on the tree Blume-leiss Altimeter Height measurements are read directly from the altimeter dependent upon fixed baseline 4 / 12  FRM 61 - Forest Biometry Study online at https://quizlet.com/_eb1q1z distances of 15m, 20m, 30m, and 40m. Held to one eye and raised or lowered until the hairline is seen at Suunto Clinometer the point of measurement which gives the reading is an instrument for determining Rangefinder or Hypsometer the height of trees by triangulation. Cylinder no taper Cone constant taper Paraboloid increasing taper Neiloid decreasing taper The ratio of tree volume to the volume of the cylinder that has the same basal diameter ad height as the tree. Form Factor Normally less 1. The ratio of some-upper-stem diameter to dbh. The value is always less than unity ( tree volume Forest Biomass A measure of productivity aboveground biomass, belowground bio- Carbon Pools mass, necromass, soil carbon aboveground biomass, belowground bio- Carbon Pools mass, necromass, soil carbon 5 / 12  FRM 61 - Forest Biometry Study online at https://quizlet.com/_eb1q1z It is defined as the total amount of aboveground living Aboveground Biomass organic matter in trees expressed as oven-dry tons per unit area (Brown and Lugo, 1997) WHY ESTIMATE FOREST BIOMASS? - Also a useful variable in comparing structural and functional attributes of forest ecosystems across a wide range of environmental condition A useful measure of assessing changes in forest structure - Forest Biomass = Production - Con- sumption - Changes in biomass density could be affected by silviculture, harvesting and degradation and natural impacts. WHY ESTIMATE FOREST BIOMASS? - Importance of forest in the Relevant for issues related to global carbon cycle global change - Trees are carbon sinks and carbon sources It provides the means for estimating the WHY ESTIMATE FOREST BIOMASS? amount of carbon that can be removed from the Rates of biomass production atmosphere by regrowing forests or by and upper bounds of carbon plantations sequestration. Best used for secondary to mature closed forests, growing in moist to dry climates 6 / 12  FRM 61 - Forest Biometry Study online at https://quizlet.com/_eb1q1z VOB/ha, is inventoried volume over BIOMASS DENSITY BASED ON EX- bark of tree bole ISTING VOLUME DATA inventoried volume must include all trees with a min. dbh of 10 cm ratio of inventoried volume for all trees with a minimum diameter of 10 cm and Volume Expansion Factor above to inventoried volume for all trees with a minimum diameter of 25 - 30 cm Developed for broadleaf forests from a database that includes trees of many species harvested from forests from all three BIOMASS DENSITY BASED ON BIO- tropical regions MASS REGRESSION EQUATIONS Database stratified into three main climatic zones: dry, wet and moist zones Tree Diameter Important Variables om Tree Volume Tree Height Computation Tree Form Relationship between height and diame- ter Relationship between volume and tree diameter Relationship between volume and height 7 / 12  FRM 61 - Forest Biometry Study online at https://quizlet.com/_eb1q1z Relationship between volume and D2H a table showing the average volume of trees, logs or sawntimber for one or more Volume Table given characteristics such as DBH alone or DBH and height or DBH, height and form or taper 1. Local volume equation 2. Regional volume equation TYPES OF VOLUME EQUATIONS 3. General or standard volume equation applicable for a small forest or land area and are based on only one variable, i.e. DBH The basic assumption is that trees of a LOCAL VOLUME EQUATION given species, at a given location, with the same DBH, will have the same height and form. This assumption is only valid as long as site conditions are homoge- nous This type of equation is normally based on two variables (e.g. DBH and height) and covers a larger geographical area. Regional vol- ume equations are standard volume REGIONAL VOLUME EQUATION equations with limited application. Care needs to be taken that the trees mea- sured, for the formulation of this equa- tion, are truly representative of the varia- tion encountered in the region. In the Philippines, there are already _ 7 existing standard volume equations for different regions: 8 / 12  FRM 61 - Forest Biometry Study online at https://quizlet.com/_eb1q1z General or standard volume equation is an even broader equation and covers STANDARD VOLUME EQUATION the full distribution of the species. It is normally based on two variables such as DBH and height. In this method, 40-50 individuals of a par- ticular species, representing all diameter classes of interest are selected randomly and felled. Each tree is cut into appropriate lengths of logs, generally between 2-3 m. The volume of each log Destructive method is calculated individually, using suitable formulae, generally Huber's formula for parabolides, cylin- drical, conical or Newton's formula for neiloidic form. The volume of each individual log is added to obtain the total volume of the tree. This is similar to the destructive method but the trees are not felled. Diameters are measured at different heights by climbing the trees. Tree height is estimated with the help of Non-destructive method e.g. an altimeter, a clinometer, a cruiser stick or a relaskop. The volume is then calculated using the same formulae as above. Volume tables can be prepared for particular species, on the basis of these calculations. What is the most commonly used tech- Regression Analysis nique in developing the volume equation for the construction of volume table? Deals with the study of relationship between or among variables where Regression Analysis the variation of one variable is believed to be dependent on the 9 / 12  FRM 61 - Forest Biometry Study online at https://quizlet.com/_eb1q1z variation of the second variable, called independent variable. To have a rough idea of the relationship between 2 variables, it Scattergram is important to plot the n sample points in a two dimensional axis Positive Linear Relationship Negative Linear Relationship Forms of Scattergram No Relationship Non-linear Relationship study of linear relationship between two Simple Linear Regression variables when the number of independent vari- Multiple Linear Regression ables is more than one is used to test the significance of these t-test regression statistics. Gives the range of values where the pop- ulation parameter lies Confidence Intervals Has 2 confidence limits, the upper confi- dence limits (UCL) and the lower confidence limits (LCL) Another way of testing the significance ANOVA of the slope is by using F-test, which is facilitated by the construction of this A measure of how well a regression line Coefficient of Determination fits the sample data - deals with the linear relationship among variables. Multiple Linear Regression - involves the estimation of a dependent variable from two or more independent variables. - concerned with the nonlinear relation- Non-linear Regression ship between or among variables. 10 / 12 FRM 61 - Forest Biometry Study online at https://quizlet.com/_eb1q1z is the systematic collection of data on the forestry resources within a given area. It allows assessment of the current sta- Forest Inventory tus and lays the ground for analysis and planning, constituting the basis for sus- tainable forest management. Provides information on the resources according to species composition, ownership and manage- ment status, size of holdings, standing volume and growing stock, felling and re- movals and their management and uses Forest Resource Inventory Monitors the extent of forest and forest cover change over time Supports decision-making for forestry policies and programs at the sub-national, national, regional and international level adopted probabilistic (statistical) sam- pling. The sample consists of a certain number of sampling units, where tree, stand or site characteristics are count- ed, assessed or measured in circular sub-national FRAs plots spatially arranged around the sam- ple points. If the sample point associated to the sampling unit falls into the areal sampling frame, the sampling unit is to be measured. consisted of key forest strata, namely closed forests and open forests. Man- groves have been excluded from the areal sampling frames FRAs, because they represent less than 5% of the total forest area of the project sites. Due to cost and time constraints invento- sampling techniques ries are generally carried out using 11 / 12 FRM 61 - Forest Biometry Study online at https://quizlet.com/_eb1q1z deals with the determination of dimensions, form, weight, growth, vol- ume and age of trees, Forest Mensuration individually or collectively, and the di- mension of their products. 12 / 12