biomass                 package:CTFS                 R Documentation

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_S_p_e_c_i_e_s

_D_e_s_c_r_i_p_t_i_o_n:

     Computes the above ground biomass for individual trees for 2
     censuses including biomass of main stem, any and all multiple
     stems  and total for tree.  Growth rate used for the computation
     is also provided.  The biomass is computed using the models in
     Chave, J. et.al. (2005).

_U_s_a_g_e:

     biomass(census1, census2, mult1 = NULL, mult2 = NULL, wsgfile = NULL, 
             forest = NULL, badgrowth = "meangrowth", dbhuse = "second", 
             trim = c(-5, 75), recsize = 110, rounddown = FALSE)

_A_r_g_u_m_e_n_t_s:

 census1: name *dataframe* of first census, must be of same length as
          'census2'

 census2: name *dataframe* of second census, must be of same length as
          'census1'

   mult1: name of *dataframe* with dbh measurements of secondary stems
          of census1.  Tree tag numbers can appear multiple times in
          this file if there is more than two stems for a tree.

   mult2: name of *dataframe* with dbh measurements of secondary stems
          of census2.  Tree tag numbers can appear multiple times in
          this file if there is more than two stems for a tree.

 wsgfile: name of the *dataframe* that contains wood density values for
          selected species. See 'tst.ctfs.wsg' 

  forest: parameter indicating forest type which affects the
          coeficients used to compute above ground biomass.  Valid
          values are  "wet", "moist", "dry" and NULL.  The last results
          in a computation based on coefficients based on all forest
          types, a "mean" value.

badgrowth: parameter indicating how to handle trees with "bad" growth.
          "bad" growth is defined by 'trim'. Valid values are: "keep"
          for retaining  all bad growth rates without alteration,
          "nogrowth" for setting bad growths to 0, "meangrowth" for
          setting bad growth to the mean value of the dbh size class of
          the tree, "trim" for using the values of 'trim' to set growth
          to maximum and minium as appropriate.

  dbhuse: indicate which 'dbh' to use for computing growth  after
          implementing value of 'badgrowth'.  Valid values are: "first"
          for the dbh in the first census, "second" for  dbh in the
          second census.

    trim: minimum and maximum value of growth that is considered
          acceptable when 'badgrowth' = "trim"

 recsize: the maximum DBH (mmm) a recruit to the second census that is 
          considered appropriate, a very site and species specific
          value that  should be carefully determined by the user.

rounddown: how to round down values of growth for trees enumerated  at
          Pasoh in 1990 due to a measurement standard. See
          'CTFS.datafiles'

_D_e_t_a_i_l_s:

     This function computes above ground biomass relying upon
     coefficients and models presented in Chave, J. et.al. (2005) (see
     references below). The function can be used to explore the impact
     of different choices for handling mismeasured dbh which affect
     growth rates.  See 'CTFS.biomass' for further details.

     This function makes NO selection of records.  The returned object
     is of the same length and structure as the input file.  Use this
     object for further analysis of biomass for instance with
     'biomass.change'.

_V_a_l_u_e:

     Returns a *dataframe* with row of 'tag' numbers and the following
     columns: 

     tag: tree tag number, same as in CTFS main dataset

 errtype: indication of whether a DBH was estimated for AGB, values 
          are:

   AGBm1: above ground biomass of main stems in census1

   AGBm2: above ground biomass of main stems in census2

   AGBs1: summed above ground biomass of all secondary stems in census1

   AGBs2: summed above ground biomass of all secondary stems in census2

   AGBt1: summed above ground biomass of main and secondary stems in
          census1

   AGBt2: summed above ground biomass of main and secondary stems in
          census1

_N_o_t_e:

     This function calls the following functions which are specific for
     'biomass': 'pick.dbh', 'getwsg.vct', 'agb.ind', 'agb.mult',
     'gr.raw', 'growth.dbh',  'trim.growth' and 'badgrowth.tree'

_A_u_t_h_o_r(_s):

     Pamela Hall

_R_e_f_e_r_e_n_c_e_s:

     Chave, J. et.al.(2005). Tree allometry  and improved estimation of
     carbon stocks and balance in tropical  forests. Oecologia. 145. pg
     87

_S_e_e _A_l_s_o:

     'CTFS.biomass'

_E_x_a_m_p_l_e_s:

     ## Not run: 
     1.  AGB in 1990 and 1995 for BCI which is a moist forest, use mean growth
     for dbh class as replacement for bad growth rates and rely upon the dbh in
     1995 (second).

     bci9095.biomass <- biomass(bci90.full,bci95.full,mult1=tst.bci90.mult,mult2=tst.bci95.mult,wsgfile=wsg.ctfs,
             forest="moist",badgrowth="meangrowth",dbhuse="second",trim=c(-5,75),recsize=110,rounddown=FALSE)
       ## End(Not run)

