Revised biomass equations
advertisement
Technical Specification for the Biomass Equations Developed for the 2011 Forecast Tim Randle Robert Matthews Tom Jenkins Mensuration Revised Biomass Equations Existing crown and root biomass equations overestimate the biomass content of larger trees. Revised equations have therefore been prepared for estimating the crown and root biomass, in oven-dry tonnes, of tree species grown in Great Britain. The form of these equations is presented below, together with the species-specific parameters to be used. Crown biomass equations Three separate equations have been developed for estimating the biomass contained in tree crowns. All three equations use diameter at breast height (dbh) as the input variable, and the equation used is dictated by the dbh of the tree being assessed. Crown biomass includes the tip, branches, twigs and foliage. Crown biomass equation for trees with dbh < 7 cm A tree of less than 7 cm dbh is assumed to contain no merchantable stem volume. The output of the crown biomass equation for trees of less than 7 cm dbh therefore incorporates the biomass, in oven-dry tonnes, contained in the tree stem in addition to the biomass contained in the crown (i.e. all above-ground tree biomass). The format of the equation is: Above-ground biomass(dbh < 7 cm) = b × dbhp Equation 1 where b and p are species-specific parameters, and dbh is diameter at breast height (1.3 m) less than 7 cm. The values for the species-specific parameters for use in Equation 1 are presented in Table 1. Table 1: Species/group-specific coefficients for Equation 1, the above-ground biomass equation for trees less than 7 cm dbh. Species/species group b p larches 0.0002855835 1.459047 Corsican pine 0.0002341451 1.459047 lodgepole pine 0.0002693744 1.459047 Scots pine 0.0002694943 1.459047 firs, spruces, cedars and hemlocks 0.0001047720 1.459047 Douglas fir 0.0002710716 1.459047 beech 0.0001172993 2.000000 oak 0.0001136009 2.000000 2 | Revised biomass equations | Randle, Matthews & Jenkins | 27/01/2014 Mensuration Crown biomass equation for trees with dbh 7 cm to 50 cm The output of the crown biomass equation for trees between 7 cm and 50 cm dbh gives an estimate of the biomass, in oven-dry tonnes, contained in the above-ground parts of the tree, excluding the merchantable tree stem biomass (i.e. excluding the part of the stem accounted for in M1 and/or Forest Yield in the Forecast System). The format of the equation is: Crown biomass(7 cm ≤ dbh ≤ 50 cm) = b × dbhp Equation 2 and p are species-specific parameters, and dbh is diameter at breast height (1.3 m) between 7.0 cm and 50.0 cm. The values for the species-specific parameters for use in Equation 2 are presented in Table 2. Table 2: Species/group-specific coefficients for Equation 2, the crown biomass equation for trees between 7 cm dbh and 50 cm dbh. Species/species group b p larches 0.0000438717 2.0291 Corsican pine 0.0000122645 2.4767 lodgepole pine 0.0000176287 2.4767 Scots pine 0.0000161411 2.4767 firs, spruces, cedars and hemlocks 0.0000144620 2.4767 Douglas fir 0.0000168602 2.4767 beech 0.0000188154 2.4767 oak 0.0000168513 2.4767 Crown biomass equation for trees with dbh > 50 cm The output of the crown biomass equation for trees with a dbh greater than 50 cm gives an estimate of the biomass, in oven-dry tonnes, contained in the above-ground parts of the tree, excluding the merchantable tree stem biomass (i.e. excluding the part of the stem accounted for in M1 and/or Forest Yield in the Forecast System). The format of the equation is: Crown biomass(dbh > 50 cm) = a + b × dbh Equation 3 where a and b are species-specific parameters, and dbh is diameter at breast height (1.3 m) greater than 50 cm. 3 | Revised biomass equations | Randle, Matthews & Jenkins | 27/01/2014 Mensuration The values for the species-specific parameters for use in Equation 3 are presented in Table 3. Table 3: Species/group-specific coefficients for Equation 3, the crown biomass equation for trees greater than 50 cm dbh. Species/species group a b larches -0.129046967 0.005039011 Corsican pine -0.299529453 0.009948982 lodgepole pine -0.430536496 0.014300429 Scots pine -0.394205622 0.013093685 firs, spruces, cedars and hemlocks -0.353197843 0.011731597 Douglas fir -0.411767824 0.013677021 beech -0.459518648 0.015263082 oak -0.411550464 0.013669801 Root biomass equations Two equations have been developed for estimating the biomass contained in tree roots (not differentiated into biomass estimates of coarse and fine roots). Both equations use diameter at breast height (dbh) as the input variable, and the equation used is dictated by the dbh of the tree being assessed. Root biomass equation for trees with dbh ≤ 30 cm The output of the root biomass equation for trees up to and including 30 cm dbh estimates the total biomass, in oven-dry tonnes, contained in tree roots (i.e. not differentiated into biomass estimates of coarse and fine roots). The format of the equation is: Root biomass(dbh ≤ 30 cm) = b × dbh2.5 Equation 4 where b is a species-specific parameter, and dbh is diameter at breast height (1.3 m) in centimetres. The values for the species-specific parameter for use in Equation 4 are presented in Table 4. 4 | Revised biomass equations | Randle, Matthews & Jenkins | 27/01/2014 Mensuration Table 4: Species/group-specific coefficients for Equation 4, the root biomass equation for trees up to and including 30 cm dbh. Species/species group b western red cedar, noble fir, Corsican pine 0.000010722 Norway spruce 0.000011883 grand fir, Scots pine, western hemlock 0.000015404 Douglas fir, Japanese larch, lodgepole pine 0.000017326 Sitka spruce 0.000020454 red alder 0.000022700 Root biomass equation for trees with dbh > 30 cm The output of the root biomass equation for trees greater than 30 cm dbh estimates the total biomass, in oven-dry tonnes, contained in tree roots (i.e. not differentiated into biomass estimates for coarse and fine roots). The format of the equation is: Root biomass(dbh > 30 cm) = a + b × dbh Equation 5 where a and b are species-specific parameters, and dbh is diameter at breast height (1.3 m) greater than 30 cm. The values for the species-specific parameters for use in Equation 5 are presented in Table 5. Table 5: Species/group-specific coefficients for Equation 5, the root biomass equation for trees greater than 30 cm dbh. Species/species group a b western red cedar, noble fir, Corsican pine -0.082602857 0.004515233 Norway spruce -0.091547262 0.005004152 grand fir, Scots pine, western hemlock -0.118673233 0.006486910 Douglas fir, Japanese larch, lodgepole pine -0.133480423 0.007296300 Sitka spruce -0.157578701 0.008613559 red alder -0.174882004 0.009559391 5 | Revised biomass equations | Randle, Matthews & Jenkins | 27/01/2014 Mensuration Species mapping The quantities of data available for calibrating revised biomass equations for use in Great Britain are generally insubstantial, variable, and do not cover all species commonly grown as forest trees. In order to satisfactorily calibrate the revised biomass equations, it has been necessary to pool data according to apparent statistical similarities. This approach has resulted in slightly different species groupings for crown and root biomass. The revised biomass equations were subsequently subjectively assigned (“mapped”) to species for which no suitable calibration data existed, on the basis of perceived similarities in silvicultural and morphological characteristics. The resultant species mappings are presented in Tables 6 and 7. This approach is entirely consistent with mapping exercises that have previously been carried out for other growth and yield models applied to tree species in Great Britain. Table 6: Species mappings for broadleaves. PF Code 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 6 | FC Code OK POK SOK ROK BE SY NOM AH BI PO SC HCH AR CAR GAR RAR SAR VAR LI CLI SLI Species name Oak Pedunculate oak Sessile oak Red oak Beech Sycamore Norway maple Ash Birch Poplar Sweet chestnut Horse Chestnut Alder Common alder Grey alder Red alder Sitka alder Green alder Lime Common Lime Small-leaved lime Revised biomass equations | Mapping for Crown Biomass Functions oak oak oak oak beech beech beech oak oak oak beech oak oak oak oak oak oak oak oak oak oak Mapping for Root Biomass Functions red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder Randle, Matthews & Jenkins | 27/01/2014 Mensuration Table 6 (continued): PF Code 55 56 57 58 59 60 61 62 63 64 65 66 67 68 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1037 1039 1053 1054 7 | FC Code LLI EM EEM WEM SEM WCH BCH HBM RON RAN DUM XB MB HAZ WWL WPO GPO XB2 BPO XB9 XB5 IAR XB12 QIL XB4 XB17 XB15 TUL LPL XB14 XB13 WHI FM WL ROW ASP HOL HAW QCE QFR Species mappings for broadleaves. Species name Large-leaved lime Elm English elm Wych elm Smooth-leaved elm Wild cherry, gean Bird cherry Hornbeam Roble Raoul Dummy Other broadleaves Mixed broadleaves Hazel White willow White poplar Grey poplar Aspen Black poplar Hybrid black poplar Eastern cottonwood Italian alder Pin oak Holm oak Cork oak Turkey oak Small-leaved elm Tulip tree London plane Service tree Rowan Common whitebeam Field maple Willow Rowan Aspen Holly Hawthorn Turkey oak Hungarian oak Revised biomass equations | Mapping for Crown Biomass Functions oak oak oak oak oak oak oak beech beech beech oak oak oak oak oak oak oak oak oak oak oak oak oak oak oak oak oak beech beech oak oak oak beech oak oak oak beech oak oak oak Mapping for Root Biomass Functions red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder Randle, Matthews & Jenkins | 27/01/2014 Mensuration Table 6 (continued): PF Code 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1090 8 | FC Code QPY QPU JRE QAL XOK XWA JNI ENI XEU XPO NPU XNO FAM ASA BPA SCI CAP FPE BOX EGU PBI CWL FM GWL AMA WST FAN PSP SBI XWL XBI XCH XPL COV FOR Species mappings for broadleaves. Species name Pyrenean oak Downy oak Common walnut White oak Other oak Other walnut Black walnut Shining gum Other eucalyptus Other poplar Lenga Other Nothofagus White ash/american ash Silver maple Paper bark birch Grey willow Crab apple Red ash Box Cider gum Downy birch Crack willow Field maple Goat willow Big leaf maple Wild service tree Narrow-leafed ash Blackthorn Silver birch Other willows Other birch Other cherry Other plane Shagbark hickory Oriental beech Revised biomass equations | Mapping for Crown Biomass Functions oak oak oak oak oak oak oak oak oak oak beech beech oak beech oak oak oak oak beech oak oak oak beech oak beech oak oak oak oak oak oak oak beech oak beech Mapping for Root Biomass Functions red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder red alder Randle, Matthews & Jenkins | 27/01/2014 9 | Table 7: Revised biomass equations | | 27/01/2014 FC Code SP CP LP AUP MAP WEP MOP BIP RAP PDP MCP XP SS NS OMS XS EL JL HL DF WH RC LC LEC GF NF ESF XF JCR RSQ WSQ XC Species name Scots pine Corsican pine lodgepole pine Austrian pine maritime pine Weymouth pine mountain pine Bishop pine Monterey/Radiata pine ponderosa pine Macedonian pine other pines Sitka spruce Norway spruce Omorika spruce other spruces European larch Japanese larch hybrid larch Douglas fir western hemlock western red cedar Lawsons cypress Leyland cypress grand fir noble fir silver fir other firs (abies) Japanese cedar coast redwood Wellingtonia other conifers Mapping for Crown Biomass Functions Scots pine Corsican pine lodgepole pine Corsican pine lodgepole pine Corsican pine lodgepole pine Corsican pine Corsican pine Corsican pine Corsican pine Scots pine firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks larches larches larches Douglas fir firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks Mapping for Root Biomass Functions grand fir, Scots pine, western hemlock western red cedar, noble fir, Corsican pine Douglas fir, Japanese larch, lodgepole pine western red cedar, noble fir, Corsican pine Douglas fir, Japanese larch, lodgepole pine western red cedar, noble fir, Corsican pine Douglas fir, Japanese larch, lodgepole pine western red cedar, noble fir, Corsican pine western red cedar, noble fir, Corsican pine western red cedar, noble fir, Corsican pine western red cedar, noble fir, Corsican pine grand fir, Scots pine, western hemlock Sitka spruce Norway spruce Norway spruce Norway spruce Douglas fir, Japanese larch, lodgepole pine Douglas fir, Japanese larch, lodgepole pine Douglas fir, Japanese larch, lodgepole pine Douglas fir, Japanese larch, lodgepole pine grand fir, Scots pine, western hemlock western red cedar, noble fir, Corsican pine western red cedar, noble fir, Corsican pine western red cedar, noble fir, Corsican pine grand fir, Scots pine, western hemlock western red cedar, noble fir, Corsican pine grand fir, Scots pine, western hemlock western red cedar, noble fir, Corsican pine western red cedar, noble fir, Corsican pine grand fir, Scots pine, western hemlock grand fir, Scots pine, western hemlock Norway spruce Mensuration Randle, Matthews & Jenkins PF Code 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 Species mappings for conifers. 10 | Table 7 (continued): Revised biomass equations | | 27/01/2014 FC Code MC XF2 NMF ORS XS2 XS4 XS1 XC3 XC1 PMO MET XC4 XC5 XC6 JUN YEW CAT XCD PAY PBR PKO PWA PYU BMF LCD GKF PAR PTA XL RF PEL Species name mixed conifers Siberian fir Nordmann/Caucasian fir oriental spruce white spruce Engelmann spruce blue spruce deodar cedar Atlantic cedar western white pine dawn redwood Monterey cypress Nootka cypress yew juniper yew Atlas cedar other cedar Mexican white pine Calabrian pine Korean pine Bhutan pine Yunnan pine Bornmuller's fir cedar of Lebanon Greek fir Armand's pine loblolly pine other larches red (pacific silver) fir slash pine Mapping for Crown Biomass Functions firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks Scots pine Scots pine Corsican pine firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks firs, spruces, cedars and hemlocks Scots pine Scots pine Scots pine lodgepole pine Scots pine Corsican pine Scots pine firs, spruces, cedars and hemlocks Scots pine firs, spruces, cedars and hemlocks Scots pine Corsican pine larches firs, spruces, cedars and hemlocks lodgepole pine Mapping for Root Biomass Functions Norway spruce western red cedar, noble fir, Corsican pine western red cedar, noble fir, Corsican pine Norway spruce Norway spruce Norway spruce Norway spruce grand fir, Scots pine, western hemlock grand fir, Scots pine, western hemlock western red cedar, noble fir, Corsican pine grand fir, Scots pine, western hemlock western red cedar, noble fir, Corsican pine western red cedar, noble fir, Corsican pine western red cedar, noble fir, Corsican pine western red cedar, noble fir, Corsican pine western red cedar, noble fir, Corsican pine grand fir, Scots pine, western hemlock grand fir, Scots pine, western hemlock grand fir, Scots pine, western hemlock Douglas fir, Japanese larch, lodgepole pine grand fir, Scots pine, western hemlock western red cedar, noble fir, Corsican pine grand fir, Scots pine, western hemlock western red cedar, noble fir, Corsican pine grand fir, Scots pine, western hemlock western red cedar, noble fir, Corsican pine grand fir, Scots pine, western hemlock western red cedar, noble fir, Corsican pine Douglas fir, Japanese larch, lodgepole pine western red cedar, noble fir, Corsican pine Douglas fir, Japanese larch, lodgepole pine Mensuration Randle, Matthews & Jenkins PF Code 33 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1036 1038 1040 1041 1042 1043 1044 1045 1046 1048 1049 1051 1089 1091 1092 1093 1094 Species mappings for conifers.
