TABLE 2--Summary statistics for subunit surveys

 Parameter Type                                   Value

 NNH3      number of nonmissing values, P00608    958.000
 NNO2      number of nonmissing values, P00613    959.000
 NAON      number of nonmissing values, P00623    910.000
 NNO3      number of nonmissing values, P00631    959.000
 NP        number of nonmissing values, P00666    911.000
 NPO4      number of nonmissing values, P00671    958.000
 NWL       number of nonmissing values, P72019    712.000
 MNH3      the mean, P00608                         0.106
 MNO2      the mean, P00613                         0.009
 MAON      the mean, P00623                         0.200
 MNO3      the mean, P00631                         2.297
 MP        the mean, P00666                         0.052
 MPO4      the mean, P00671                         0.044
 MWL       the mean, P72019                        58.414
 STDNH3    the standard deviation, P00608           0.305
 STDNO2    the standard deviation, P00613           0.046
 STDAON    the standard deviation, P00623           0.381
 STDNO3    the standard deviation, P00631           5.021
 STDP      the standard deviation, P00666           0.135
 STDPO4    the standard deviation, P00671           0.124
 STDWL     the standard deviation, P72019          95.906
 MEDNH3    the median, P00608                       0.020
 MEDNO2    the median, P00613                       0.005
 MEDAON    the median, P00623                       0.100
 MEDNO3    the median, P00631                       0.490
 MEDP      the median, P00666                       0.020
 MEDPO4    the median, P00671                       0.010
 MEDWL     the median, P72019                      25.795