dylanbeaudette
commented
5 years ago Where might this be an issue:
- ECEC is more appropriate at pH <= 5.5
- CEC7 is NULL at pH <= 5.5 (due to NASIS calculations)
- O horizons: often low pH and CEC is NULL
Examples
CECIL is a nice place to start, but it looks like CEC7 and ECEC are populated for many of these components.
select cokey, hzname, hzdept_r, hzdepb_r, cec7_r, ecec_r, ph1to1h2o_r
FROM ssurgo.chorizon
where cokey = '16755449'
order by hzdept_r;
cokey | hzname | hzdept_r | hzdepb_r | cec7_r | ecec_r | ph1to1h2o_r
----------+--------+----------+----------+--------+--------+-------------
16755449 | A | 0 | 15 | 2.1 | 1.6 | 5.3
16755449 | Bt | 15 | 107 | 5.7 | 4.9 | 5
16755449 | BC | 107 | 203 | 3.7 | 3.6 | 5O horizons:
select mukey, compname, cokey, hzname, hzdept_r, hzdepb_r, cec7_r, ecec_r, ph1to1h2o_r
FROM ssurgo.chorizon
JOIN ssurgo.component USING (cokey)
WHERE cec7_r IS NULL AND ph1to1h2o_r <= 5.5
ORDER BY hzdept_r
LIMIT 1000;
mukey | compname | cokey | hzname | hzdept_r | hzdepb_r | cec7_r | ecec_r | ph1to1h2o_r
---------+--------------------------+----------+--------+----------+----------+--------+--------+-------------
76998 | Nard | 15923387 | Oi | 0 | 3 | | 25 | 5
76669 | Nard | 15923493 | Oi | 0 | 3 | | 25 | 5
76788 | Naxing | 15923285 | Oi | 0 | 5 | | 25 | 5
76982 | Tekison | 15923381 | Oe | 0 | 3 | | 25 | 5
77170 | Cliffdell | 15923425 | Oe | 0 | 3 | | 25 | 5
76665 | Nard | 15923490 | Oi | 0 | 3 | | 25 | 5
74189 | Everett | 15923169 | Oi | 0 | 3 | | 35 | 4.5
76718 | Saydab | 15923282 | Oe | 0 | 3 | | 25 | 5
76848 | Cliffdell | 15923349 | Oe | 0 | 3 | | 25 | 5
76975 | Tekison | 15923373 | Oe | 0 | 3 | | 25 | 5
77104 | Stirrup | 15923407 | Oe | 0 | 3 | | 25 | 5
77153 | Ainsley | 15923421 | Oe | 0 | 3 | | 25 | 5
77247 | Osborn | 15923436 | Oi | 0 | 3 | | 25 | 5
76660 | Kladnick | 15923485 | Oe | 0 | 3 | | 25 | 5
74186 | Indianola | 15923156 | Oi | 0 | 3 | | 35 | 4.5
[...]Anything other than O horizons:
-- flag components missing CEC7
CREATE TEMP TABLE missing_cec7 AS
select DISTINCT compname
FROM ssurgo.component
JOIN ssurgo.chorizon USING (cokey)
WHERE cec7_r IS NULL
AND ph1to1h2o_r <= 5.5
AND compkind IN ('Series', 'Family', 'Taxon above family');
select mukey, compname, cokey, hzname, hzdept_r, hzdepb_r, cec7_r, ecec_r, ph1to1h2o_r
FROM ssurgo.component
JOIN missing_cec7 USING (compname)
JOIN ssurgo.chorizon USING (cokey)
WHERE cec7_r IS NULL
LIMIT 1000;
mukey | compname | cokey | hzname | hzdept_r | hzdepb_r | cec7_r | ecec_r | ph1to1h2o_r
---------+---------------------------------------------+----------+------------+----------+----------+--------+--------+-------------
2858643 | Winnemucca | 17037171 | Oe | 0 | 4 | | 36.4 | 5
117007 | Tate | 16154891 | A | 0 | 8 | | 11.2 | 5.5
117007 | Tate | 16154891 | E | 8 | 15 | | 4.1 | 5.5
117007 | Tate | 16154891 | Bt1 | 15 | 38 | | 5.8 | 5.5
117007 | Tate | 16154891 | Bt2 | 38 | 66 | | 6.5 | 5.5
117007 | Tate | 16154891 | Bt3 | 66 | 127 | | 5.8 | 5.5
117007 | Tate | 16154891 | BC | 127 | 203 | | 3.2 | 5.5
22833 | Cumberland | 16710809 | H1 | 0 | 10 | | 6.2 | 5.3
522833 | Cumberland | 16710809 | H2 | 10 | 20 | | 7.4 | 5.3
522833 | Cumberland | 16710809 | H3 | 20 | 152 | | 5.9 | 5.3
1895710 | Fruithurst | 16544473 | Bt1 | 18 | 53 | | 7.8 | 5
1895710 | Fruithurst | 16544473 | Bt2 | 53 | 76 | | 2.2 | 5.2
1895711 | Fruithurst | 16544558 | BE | 8 | 18 | | 5.7 | 4.6
1895711 | Fruithurst | 16544558 | Cr | 76 | 203 | | |
1895711 | Fruithurst | 16544558 | Bt1 | 18 | 53 | | 7.8 | 5
1895711 | Fruithurst | 16544558 | Ap | 0 | 8 | | 15.6 | 4.5
1895711 | Fruithurst | 16544558 | Bt2 | 53 | 76 | | 2.2 | 5.2
1413684 | Guyton | 16669645 | A | 0 | 13 | | 4.2 | 4.6
1413684 | Guyton | 16669645 | Eg | 13 | 76 | | 10.4 | 4.6
1413684 | Guyton | 16669645 | Btg/E | 76 | 137 | | 9.5 | 4.6
1413684 | Guyton | 16669645 | Btg | 137 | 203 | | 10.1 | 4.6
[...]
NASIS calculations (component data) make the switch from CEC -> ECEC at pH <= 5.5. These data should condition "CEC" on pH for each component record that is considered.
If the rv pH (in water) is greater than 5.5 or gypsum or calcium carbonate are not low, then CEC is calculated; if the rv pH is less than or equal 5.5 (and soluble salts are low) then ECEC is calculated for a horizon. Low soluble salts are defined as caco3 < 0.05% and gypsum < 0.05%.
For example: current CEC 0-25cm, note the blank spaces: