A/R Methodological Tool

Transcription

1 Thrty-fourth meetg Page 1 A/R Methodologcal Tool Draft Tool for demostrato of approprateess of volume equatos for estmato of abovegroud tree bomass A/R CDM project actvtes (Verso ) Scope I. SCOPE, APPLICABILITY AND ASSUMPTIONS 1. Ths tool allows demostrato of approprateess of a volume equato, combato wth bomass expaso factors (BEFs) ad basc wood desty, for estmato of abovegroud tree bomass A/R CDM project actvtes. Applcablty 2. Ths tool has o teral applcablty codtos. Deftos 3. Volume equato s a equato that predcts tree stem volume o the bass of oe or more measuremets of a tree (e.g. DBH ad/or tree heght). Parameters 4. Ths tool eables the user to demostrate whether a volume equato, combato wth selected BEFs ad basc wood desty, s approprate for estmato of abovegroud tree bomass a A/R CDM project actvty. II. ASSESSMENT OF APPROPRIATNESS OF VOLUME EQUATIONS FOR ESTIMATION OF TREE STEM VOLUME Estmato of tree stem volume 5. A speces-specfc or group-of-speces-specfc volume equato derved from trees growg edapho-clmatc codtos smlar to those the project area s cosdered approprate, ad hece ca be used for ex post estmato of tree stem volume, f at least oe of the followg codtos s satsfed: (c) The equato s used the atoal forest vetory, or the atoal GHG vetory, of the host Party; The equato has bee used commercal forestry sector of the host Party for te years or more; The equato was derved from a data set of at least 30 sample trees, ad the value of coeffcet of determato (R 2 ) was ot less tha A volume equato that does ot meet the crtera provded uder paragraph 5 above ca be used for ex post estmato of tree stem volume oly f ts approprateess for stem volume estmato s demostrated o the bass of feld data obtaed from sample trees as descrbed paragraphs 7 to 15 below.

2 Thrty-fourth meetg Page 2 Selecto of sample trees 7. For each speces or group of speces of trees for whch the volume equato was developed ad wll be used the A/R CDM project, ot less tha te sample trees growg edaphoclmatc codtos smlar to those the area where the A/R CDM project actvty s mplemeted (preferably wth the project boudary) are selected. Sample trees are selected such a way that the rage of tree measuremets (e.g. DBH ad/or tree heght) preset wth the project boudary ad expected to be cluded the applcablty rage of the equato s covered a represetatve way. 1 If a tree speces s growg more tha oe stratum wth the project boudary, selecto of trees should spa across all such strata for whch approprateess of the equato s to be demostrated. Estmato of predcted stem volume of sample trees 8. The tree measuremets (e.g. DBH ad/or tree heght) used as put data the volume equato are obtaed for the sample trees. 9. The predcted stem volume of each sample tree s calculated by sertg the tree measuremets (e.g. DBH ad/or heght) to the volume equato. Measuremet of stem volume of sample trees 10. The stem volume of a sample tree s measured usg oe of the followg methods: Water dsplacemet method The sample tree s felled ad ts stem s cut to sectos that ft to a water tak (e.g. a xylometer). The peces are the put to the tak (below the water) ad the volume of water dsplaced s measured. The process s repeated for all the sectos of the stem ad volumes of the sectos are summed up to obta the tree stem volume V STEM. Sectoal dameters method () The stem of the tree (stadg or felled) s dvded to sectos ot exceedg 2 m legth, ad stem dameter at the mddle pot of each secto s measured. The volume of a secto of stem s calculated as: 2 * D M, * L 4 = *10 V π (1) 4 V Volume of th secto of stem; m 3 D M, Dameter at the mddle pot of the th secto of stem; cm L Legth of the th secto of stem; m () Tree stem volume s obtaed by summg up the volumes of the sectos of stem: 1 Represetatve coverage does ot mea uform coverage the spatal sese, represetatve s meat the statstcal sese; f a certa rage of dameters s domat, the more trees are selected that rage.

3 Thrty-fourth meetg Page 3 V STEM = V (2) V Tree stem volume; m 3 STEM V Volume of th secto of stem; m 3 Comparg the measured ad the predcted stem volume 11. Agreemet of the predcted stem volume wth the measured stem volume s tested by applyg a pared t-test to the two datasets of stem volume whch returs the probablty (the p value) that the two datasets have the same mea. A step-by-step procedure for calculatg the p value retured by a pared t-test s cotaed the Aex I of ths tool. Alteratvely, a pared t-test s appled usg statstcal software. Use of the equato for estmatg mea stem volume basele ad project 12. The volume equato s approprate for estmato of tree stem volume, the basele ad the project, f the p value retured by the t-test s equal to or greater tha 0.90 (see Aex I). Coservatve use of the equato for estmatg stem volume basele (but ot project) 13. The volume equato s approprate for estmato of tree stem volume the basele (but ot project) f the mea of measured stem volume s less tha the mea of predcted stem volume ad ay oe of the followg codtos s satsfed: The p value retured by the t-test s less tha 0.20 (see Aex I); The cofdece terval of the mea dfferece, at 90% cofdece level, does ot cota zero (see Aex II). Coservatve use of the equato for estmatg stem volume project (but ot basele) 14. The volume equato s approprate for estmato of tree stem volume the project (but ot basele) f the mea of measured stem volume s greater tha the mea of predcted stem volume ad ay oe of the followg codtos s satsfed: The p value retured by the t-test s less tha 0.20(see Aex I); The cofdece terval of the mea dfferece, at 90% cofdece level, does ot cota zero (see Aex II). Modfcato of a equato 15. A volume equato whch s ot cofrmed as approprate uder paragraphs 12, 13, or 14 may be modfed (e.g. by applcato of a multpler or by modfyg coeffcets) such a way that t becomes approprate uder ay of these paragraphs.

4 III. USE OF VOLUME EQUATIONS FOR ESTIMATION OF ABOVEGROUND TREE BIOMASS Thrty-fourth meetg Page 4 Estmato of tree bomass based o volume equato 16. Estmato of abovegroud tree bomass requres a volume equato to be used combato wth BEF ad basc wood desty. 17. The DOE shall assess that the product of volume (calculated usg the approprate volume equato) ad the value of BEF proposed by project partcpats ad basc wood desty yelds coservatve estmates of abovegroud tree bomass usg the latest verso of the Gudeles o coservatve choce ad applcato of default data estmato of the et athropogec GHG removals by sks. IV. DATA AND PARAMETERS USED IN THE TOOL 18. The followg tables descrbe the data ad parameters used ths tool. The gudeles cotaed these tables regardg selecto of data sources, ad procedures to be followed measuremet, where applcable, should be treated as a tegral part of ths tool. Data ad parameters ot measured y Data ut: m 3 Used equatos: Descrpto Source of data: Equato (1), Equato (2) of Aex I Stem volume of the th sample tree as predcted by the volume equato Predcted stem volume s calculated by sertg the relevat tree measuremets (e.g. DBH ad/or heght) to the volume equato Data ad parameters measured Y Data ut: m 3 Used equatos: Descrpto: Measuremet procedures: Equato (1), Equato (2) of Aex I Stem volume of the th sample tree as obtaed from feld measuremets Measured as descrbed uder paragraph 10 or 10 of ths tool Data ut: D M, cm Used equatos: Equato (1)

5 Descrpto: Measuremet procedures: Stem dameter at mddle pot of the th sample tree Thrty-fourth meetg Page 5 The tree stem s dvded to sectos ot exceedg 2 m legth. At the mddle pot of each secto, dameters two perpedcular drectos are measured ad ther geometrc mea s used as the dameter of the secto L Data ut: m Used equatos: Equato (1) Descrpto: Measuremet procedures: Legth of a th stem secto The ed pots of a stem secto are marked ad ts legth of the secto s measured wth a tape V. REFERENCES IPCC, Good Practce Gudace for Lad Use, Lad-Use Chage ad Forestry, prepared by the Natoal Greehouse Gas Ivetores Programme, Jm Pema, Mchael Gytarsky, Taka Hrash, Thelma Krug, Da Kruger, Rtta Ppatt, Leadro Bueda, Kyoko Mwa, Todd Ngara (eds). Publshed: IGES, Japa. < IPCC, IPCC Gudeles for Natoal Greehouse Gas Ivetores, prepared by the Natoal Greehouse Gas Ivetores Programme, Egglesto H.S., Bueda L., Mwa K., Ngara T. ad Taabe K. (eds). Publshed: IGES, Japa. <

6 Thrty-fourth meetg Page 6 Aex I Step by step procedure for calculato of p value a pared t-test (see paragraph 11) 1. Calculate the followg values: A = B = = 1 = 1 ( Y y ) ( Y y ) 2 (1) (2) Y y Stem volume of the th sample tree as determed from feld measuremet; t d.m. Stem volume of the th sample tree as predcted by the volume equato; t d.m. Value A s a sum of dffereces betwee the stem volume as estmated from feld measuremet ad as predcted by the equato. Value B s a sum of squared dffereces betwee the stem volume as estmated from feld measuremet ad as predcted by the equato. 2. Calculate value S as follows: S = 2 * B A *( 1) (3) Number of sample trees Value S s kow as varace of the dfferece betwee stem volume as determed from feld measuremet ad as predcted by the equato. 3. Calculate value E as follows: E = S (4) Value E s kow as stadard error of the mea dfferece of stem volume. 4. Calculate test value t as follows: t = A * E (5) The value t s kow as Studet s t statstc wth -1 degrees of freedom.

7 Thrty-fourth meetg Page 7 5. Oce a t statstc s determed, the corresposg p-value ca be foud usg a table of values from Studet's t-dstrbuto. Alteratvely, the p-value for a gve t-value ca be looked up usg a spreadsheet fucto, such as the Excel fucto TDIST(t,df,a)as follows: p = TDIST(t,df,a) df=-1 ad t t-value calculated Equato (4) a Apply a = 2 for cases descrbed the paragraphs Hstory of the documet Verso Date Nature of revso EB 65, Aex # 25 November 2011 To be cosdered at EB 65. Decso Class: Regulatory Documet Type: Tool Busess Fucto: Methodology