ROCZNIKI GLEBOZNAWCZE, T. X X X II, NR 3, W ARSZA W A 1981
PIO T R KO W ALIK
PROGRAM OF YIELD PROGNOSIS IN SOIL INFORMATION SYSTEM BIGLEB
G dańsk T ech n ica l U n iv e r sity IN TR O D U C TIO N
The aim of the respective investigations was to work out com puter program s for data processing concerning soil, climate and vegetation, in such a way, so as to obtain the values of crop yields.
The general idea of yield prognosis is based on proposal by T.C. de Wit (1965) to calculate potential productivity of fields crops, limited, first of all, by vegetal and climatic factors for optimum (not limiting the plant growth) soil conditions and afterw ards to calculate actual produc tivity and yielding lim ited by w ater deficiencies and lack of nutrients in soil. This method was applied, among others, by J. B uringh (1975), who jointly w ith his co-workers in the N etherlands worked out the map of potential (maximum possible) productivity of world soils. Recent recommendations of FAO (comp. J. Doorenbos and A. H. Kassam, 1979) propagate to a wide extent the m ethod mentioned, definiting it as “the W ageningen m ethod,” w hat is fully justified, as in this D utch scientific centre the works of the Wit, B uringh as well as of R. A. Feddes (1971), P. Kowalik (1973) and R. A. b^eddes, P. Kowalik and H. Zaradny (1978) concerning the same problem, appeared. In Poland the outline of this m ethod was presented by P. Kowalik (1976, 1979) and T. Brandyk et al. (1979, 1981). Respective calculations were carried out for m any crops, among others for red cabbage, meadow plants, potatoes, beets, wheat, rice. The com puter program s set up, published in the book of R. A. Fed des et al. (1978), were applied for estim ation of w inter w heat production (G. Sanesi, P. Kowalik, 1980). Below, the problem of predicting yields, exemplified by w heat cultivated on heavy hydrom orphic soils, is discus sed.
C A L C U L A T IO N P R IN C IP L E S
252 P. K o w a lik
prediction of yielding, either as the biomass of the whole crop, or as the yield useful from economic viewpoint e.g. of straw and grain or sole grain, should be done. For the realization of prognoses the com puter sim ulation model of w ater consumption and yielding of plants, develop
m ent by R. A. Feddes et al. (1978), as well as the m easurem ent data gathered in the respective field experim ents, enabling to determ ine a num ber of param eters concerning w heat, were applied. Beside p ara m eters characterizing the grow th and development of plants, also neces sary input data and m easurem ent results, which served for the estimation of reliability and accuracy of the results obtained in prognosis calcula tions, were collected.
The potential productivity lim ited only by climatic conditions is calculated according to the form ula (1) :
proposed by C. T. de Wit (1965) and modified by P. E. Rijtem a and G. Endrödi (1970), R. A. Feddes (1971) and R. A. Feddes and co-workers (1978).
In the equation (1) we have :
Rc — sum m ary daily radiation (wave length of 0.4-0.7 um) for cloud less sky (W/m2),
R s — m easured global solar radiation (W/m2),
P j — daily photosynthetic production of the standard canopy at fully clouded sky (kg • h a- 1 • d a y -1),
Pc — daily photosynthetic production of the standard canopy at cloudless sky (kg • h a- 1 • day'-1),
Ф — respiration coefficient (a p a rt of unit, dimensionless, for w heat = 0.75),
at — coefficient considering the tem perature effect on the photosynthe sis (a p art of unit, dimensionless, for w heat it has been assumed
th a t at = 0 for 0°C, at= 0 .8 for 5°C, at = 1 for tem peratures of 10-25°C),
S c — coefficient of soil cover by plants (a p art of unit, dimensionless), ßh — coefficient considering the share of the economically useful yield in the whole plant biomass, determ ined from the relation between the useful yield and the whole biomass (dimensionless).
In the form ula (1) the input values for calculations are R* , P* and P v, sim ilarly as daily air tem peratures, values of the coefficient of soil cover by plants and daily values of solar radiation connected w ith the actual cloudiness state.
Y ield p rogn osis in BIG L E B sy stem 253
derived by W. C. Visser (1969), modified by P. Kowalik (1973, 1974, 1979) and W. C. Visser and P. Kowalik (1974) and adapted by R. A. Fed-des et al. (1978) to computations of the electronic digital machines.
In the equation (2) we have : Qa — actual cum ulative yield (kg/ha),
г — day of the grow th under consideration, counting from the first
day (i = t 0) to the last day ( i = t e), At — time step equal to 24 hours,
A — m axim um possible effectiveness of the field w ater consumption (kg • h a“ 1 • m m"“1 • m bar — for w heat the A value has been assu med for = 260, according to own computations),
Ae — w ater vapour pressure deficit in air (mbar),
Epi — actual transpiration as a function of soil and plant conditions (mm/day),
q — potential daily increm ents (kg • h a- 1 • day-1) from the equation (1),
f — constant m athem atical coefficient equal to 0 . 0 1 (dimensionless).
The actual transpiration Ept from the equation (2) is calculated on the basis of values characterizing the w ater uptake by plant roots from soil s (гр) as a function of depth and time upon integrating after depth
according to the equation (3) :
z
Ep, - A t f s (yj) ds (3)
0 w here :
г — vertical distance from the soil surface downwards as positive
values (cm),
S (гр) — w ater uptake by roots from a unit soil volume (cm3 • cm- 3 • day-1).
ц) — sucking pressure of soil w ater (cm H20), equivalent to the
m atric soil w ater potential.
W ater uptake by roots, S (yj), has been calculated from the formula (4) :
S (y) = a(ip) • E ~ / L p (4)
w here :
E£ — m axim um possible transpiration (mm/day),
a (yj) — coefficient considering the availability of soil w ater to plants (between 0 and 1, dimensionless),
L p — m easured root depth of plants (cm).
254 P. K ow alik
y: :--О-ПО cm Tl20 in the genetic horizon A }) w ith the thickness of 50 cm and ïp=Q-25 cm H20 in the genetic horizon B g. Boundary values of y = 5 0 and 7; = 25 cm H20 are anaerobic points, the determ ination of which was accomplished by sim ultaneous m easurem ents of the oxygen diffusion rate (ODR) and the soil m oisture level (P. Kowalik, 1971), let to assume th a t ODR equal to 18 • 10“ 8 g 02 • cm'- 2 • m in“ 1 would be an upper lim it of the anaerobic state. Hence it can be adm itted th a t the oxygen diffusion rate tow ards roots would be a function of soil m oisture and appropriate soil w ater sucking pressures. It has been assumed th a t
и (y>) = l for 1/; = 50-600 cm in the A p horizon and \p—25-600 cm H20
in the B CJ horizon, w here the value -of 600 cm H20 is a lim it of the w ater readily available to plans. The a (ip) values decrease linearly
from 1 down to 0 between the xp values from 600 to 20 000 cm H20 ,
where the la tter value has been assumed as a wilting point.
Having appropriate a (ip), Ep and L p values, the S (y>) values could be calculated from the equation (4), but the y> values, varying both in tim e an d wit'h depth of the soil profile, rem ain still unknown. As changes in tim e occur here, one should consider unsteady state and solve in such a case the soil m oisture dynamics equation, so as to determ ine adequate yj values as functions of time and depth.
Here the equation (5) has been applied :
derived by L. A. Richards (1931) and modified by L. A. Gen Ogata et al. (1960). In the equation (5) we have :
2 — as in the equation (3),
г — time (days),
К (yj) — capillary w ater conductivity (cm/h),
S 0/;) — w ater uptake by roots from a unit soil volume (day-1),
С (ip) — soil w ater capacity equal to dO/dxp where © is volum etric
soil m oisture (cm3 • cm_a) and the relation of ip (0 ) is described by the so-called pF curve.
The equation (5) can be solved num erically upon introducing adequate boundary conditions, as it has been proved, among other things, in works of J. Kaniewska and P. K owalik (1979) and P. Kowalik and A. Miler (1979). The solution at application of the method of finite differences used in the case under consideration has been published jointly w ith the com puter program in the FORTRAN language by R. A. Feddes et al. (1978).
IN P U T D A T A A N D R E SU L T S O B T A IN E D
Y ield prognosis in BIG LE B sy stem 255
such as tem perature and relative air hum idity, wind velocity at ihe level of 2 m above surface, cloudiness or actual solar radiation, atmos pheric precipitations, are used. From data concerning soil, among other things, actual ground w ater table depths (Fig. 1) and penetration depth of plants roots into the soil profile (Fig. 2) have been taken into consideration.
F ig. 1. D a ily v a lu e s of ground w a ter ta b le dep th in th e so il tested in th e period from Jan u ary 10 to J u ly 9, 1978 (after G. S a n esi and P. K ow alik , 1980)
Fig. 2. D a ily v a lu e s of w h ea t rooting dep th s in the soil p rofile in th e period from Jan u ary 10 to J u ly 9, 1978 (after G. S a n esi and P. K ow alik , 1980)
It follows from the morphologic soil profile description th a t it can be divided into separate diagnostical horizons, viz. : A v — to the depth of 50 cm (at the depth of 30-50 cm — w ith a distinct p artial gleization A pg) and B 2g, w ith num erous ferrugineous and calcareous concretions as well as w ith m ottled gleization (at the depth of 50-90 cm). Below the CCa and R horizons are to be found. The profile is built from silty clay.
The soil suction pressure values xp (0) and capillary w ater condutivity К (0) for the A p horizon are given in Table 1 and the B 2g horizon — in Tables 1 and 2.
256 P. K owalik »oil s u c ti o n W ö / i n cm 1^0 and o f c a p i l l a r y w a te r c o n d u c t i v i t y К / 9 / i n cm/h f o x t h e d i a g n o a t i c a l An h o r i z o n Ö W e / К/0/ Q Р/0/ K/Ö/ 0 . 0 0 0 . 1 00 0 E + 0 8 0 . 9 0 З О Е -14 0.01 0 .9 9 5 0 2 1 -0 7 0 . 9 4 2 0 2 - 1 4 .0 2 .9 5 4 6 E + 0 7 .2 9 7 5 2 - 0 9 .0 3 .9 0 9 2 2 + 0 7 .5 9 4 9 2 - 0 9 .0 4 .8 6 3 8 Е Ю 7 .Ü 9 2 4 E - 0 9 .0 5 .8 1 8 5 2 » 0 7 .1 1 9 0 2 - 0 8 .0 6 .7 7 3 1 2 * 0 7 .1 4 3 7 2 - 0 8 . 0 7 .7 2 7 7 Е Ю 7 .1 7 3 5 2 - 0 3 .0 8 . 6 3 2 3E +07 .2 0 8 2 E - 0 8 .0 9 .6 3 6 9 Е -Ю 7 .2 3 8 0 2 - 0 3 • 10 .5 9 1 5 2 + 0 7 .2 6 7 7 E - 0 8 .11 .5 4 6 1 E + 0 7 .2 9 7 5 2 - 0 3 .12 .5 0 0 8 2 + 0 7 • 3 2 7 2 E - 0 8 .13 .4 5 5 4 E + 0 7 • 3 5 7 0 2 -0 8 . 1 4 .4 1 0 0 2 + 0 7 .3867E-08 .15 . 3 6 4 6 Е+ 0 7 .4 1 6 5 2 - 0 3
.16 .3192E+07 .4462E-08 .1 7 .273ÄEI-07 .4 7 6 0 2 -0 8
«13 .2 2 8 5 2 + 0 7 «5057Е-08 .1 9 .1831ВЮ 7 .5354K-08 .2 0 .1377E+07 .5652E -08 .21 .92302+06 .5 9 4 9 2 -0 8 .2 2 .46912+06 .6247E-08 .2 3 .15302+05 .6 5 4 4 2 -0 3 .2 4 . 1020E+05 •3435E-07 .2 5 .51002+04 .1 3 5 8 2 -0 6 .26 . 3060E+04 .4597E -06 .2 7 .20402+04 .1 3 1 5 2 -0 5 .2 0 .8110E+03 .4868E -05 .2 9 .61202+03 .1 4 8 4 2 -0 4 о 30 «3540Е+03 .4 1 1 3 2 -0 4 • 31 .27452+03 .9 9 9 7 2 -0 4 «32 • 1940E+03 .2 1 9 9 E -0 3 .3 3 .15302+03 .4 4 5 9 2 -0 3 • 34 .1120E+03 .8 5 9 5 E -0 3 • 35 .84002+02 о 16 12E-02 .3 6 .5600E+02 .3 0 7 1 2 -0 2 .3 7 • 3550 E+02 .6 2 3 3 2 -0 2 • 38 • 1500E+02 .1742E-01 .3 9 .7500E+01 .62 6 5 2 -0 1 .4 0 .Ю00Е+01 .1667E-01 .41 .1 0 0 0 2 -0 4 .48032+01 T a b l e 2 УУ9/ i n cm H2C and o f c a p i l l a r y w a te r c o n d u c t i v i t y К/Q / i n cm/ha f o r th e d i a g n o a t i c a l B?g h o riz o n 0 W O / К /0 / 0 W o / К /0 / 0 .0 0 0 . 1000E+08 0.8700E -14 0.01 0.968821-06 0 .1 3 5 9 2 -0 3 .02 .93762+06 . 3718E-08 .03 .90642+06 •5577E-08 .04 .37522+06 .7 4 3 4 2 -0 8 .05 .84942*06 .9 2 9 4 2 -0 8 .06 .81282+06 .1 1 1 5 2 -0 7 .0 7 .73162+06 .1 3 0 1 2 -0 7 .03 .75042»-06 .1 4 8 7 2 -0 7 .0 9 .71922+06 .1 6 7 3 2 -0 7
.1 0 „G0GOE+O6 .1359E-07 .11 .6568E+O6 .2 0 4 5 2 -0 7
.1 2 ,6 2 5 6 2 гОб .2 2 3 1 2 -0 7 .1 3 .59442+06 .2 4 1 7 2 -0 7 .1 4 . 563221 06 .2603E -07 .15 .53202+06 .2 7 8 9 2 -0 7 .16 .50032+06 .2 9 7 4 2 -0 7 .1 7 .46962+06 .3 1 6 0 2 -0 7 .1 8 .43342+06 . ЗЗ46Е-0 7 .1 9 .40722+06 .3 5 2 6 2 -0 7 .2 0 • З7602+06 •3718Е-0 7 .21 .34482+06 .3 9 0 4 2 -0 7 .22 .31362+06 .4090E-0 7 .2 3 .2824E+06 .4 2 7 6 2 -0 7 .2 4 .25122+06 .4 4 6 2 2 -0 7 .25 .21992+06 .4748E -07
.2 6 .18872+06 • 43 34E-07 .2 7 .1575E+06 .502OE-O7
.28 .12632+06 .5206E-0 7 .2 9 .95142+05 .5391E -07
.3 0 .6393E+05 .5577E -07 .31 .3273E+05 .5763E -07 .3 2 .2 ЗООЕ+О5 .5949E -07 .3 3 .1529E+05 .2890E -06 .3 4 .1122E+05 .9024E -06 • 35 .71372+04 «3089Е-05 .3 6 .32632+04 .9 0 1 8 2 -0 5 .3 7 .247OE+04 .2 1 5 0 2 -0 4 .3 3 .17442+04 .5208E-04 .3 9 .1020E+04 . I23OE-O3 .4 0 .71372+03 . 3222Е-0 3 .41 .3721E+03 .9 1 2 0 E -0 3 .4 2 .21922+03 .2346Е-0 2 .4 3 .15802+03 .57 6 0 E -0 2 .4 4 .93902+02 .1 3742-01 .4 5 .663ОЕ+02 .4 5 7 3 2 -0 1 .4 6 .255OE+02 .13802+00 .4 7 • 1800E+02 .37802+00 .48 . 1200E+02 .7O8OE+OO .4 9 .1ОООЕ-ОЗ •7140E+00
Y ield prognosis in BIG LEB sy stem 257
The values of potential up-to-date cum ulative productivity (in quin tals) from hectare, q/ha, at consideration of straw and grain jointly, are presented in Fig. 3.
F ig. 3. C alcu lated v a lu e s of p o ten tia l (upper lin e) and a ctu a l (low er line) p rod u ct iv ity and m ea su rem en t resu lts (points) in q/ha, w ith co n sid era tio n of the
p h en om en on of a n aerob iosis
Also points from field m easurem ents illustrating the biomass incre m ents have been plotted there.
It could be easily observed th a t in Fig. 3 in the period from the 1 0 0th and the 1 2 0th day of year actual biomass calculated from the model was m uch lower than th a t m easured under field conditions. It is connected w ith the presence of a shallow ground w ater table (Fig. 1) and w ith the assumption adopted in the model th a t the w ater uptake by plant roots S (yt) is only a function of soil m oisture and appropriate soil w ater suction as 'well as th a t oxygen; inflow to the p lan t root surface is only a function of the soil m oisture level. Such assumption can be correct for stabilized ground w ater depth, b u t not for the case of quick ground w ater level fluctuations. There are, true, very few known m easurem ents of the oxygen content in ground w ater table below the w ater level and in soil close above ground w ater table but according to the report of R. Q. Cannell (1977), the oxygen disappearance in waterlogged or flooded soils would last on arable lands about one week or more in the sum m er period, and longer in the w inter period. Thus, if a full oxidation of ground w ater were assumed, then, at its occurrence in the profile (originating from rainfalls) for the time shorter than
6 days, the calculation of transpiration and productivity can be carried
out, at shifting the positon of the anaerobic point to the value of yj=0 cm H20 . The sim ulation results for such a condition are presented in Fig. 4, w here a great conformity between m easured and calculated actual w heat productivity can be observed. This conform ity could be still better, if the lower line was shifted upw ards by the value of 4 q/ha, i.e. by the
258 P. K o w a lik
F ig. 4. C alcu lated v a lu e s of p o ten tia l (upper lin e) and a ctu a l (low er lin e) p rod u ct iv ity and m ea su rem en t r e su lts (points) in q /h a , w ith o u t co n sid era tio n of a n a ero - b iosis. S im u la ted y ie ld s should be in creased by 4 q /h a , i.e. by th e biom ass grow n
in th e a u tu m s period
am ount of biomass accum ulated in autum n and om itted in sim ulation calculations starting from the zero level of the biomass on Jan uary 10.
To verify the reliability of the data obtained from calculations of the soil m oisture values, the comparison of m oisture calculated and m easured in spring and early in sum m er was accomplished. The confor
m ity of m easured and calculated values was high, whereas the cor relation coefficient for the whole population of results was r = 0.896.
Also calculations aiming at proving how the change in the soil m edium would affect the yielding of w heat w ere carried out. The results presented in Fig. 5 concern the sim ulation of actual yields (lower line)
F ig. 5. S im u la ted w h e a t y ie ld s on h ea v y hydrom orphic soil. L ow er lin e — for th e ground w a te r ta b le d ep th as in F ig. 1, m ed iu m lin e — for th e d epth of 100 cm ,
up m ost lin e — for th e dep th of 200 cm
Y ield p rognosis in BIG LE B sy stem 259
at the depth of 1 0 0 cm the yields are represented by the middle line, whereas for th a t at the depth of 2 0 0 cm the yields correspond w ith the upmost line. From sim ulation calculations of this type the relationship between the ground w ater table in the heavy hydrom orphic soil under
study and the biomass yields (straw + g rain ) as in Fig. 6 has been
Fig. 6. R elationship derived from sim u lation b etw een the ground w ater table d epth m h ea v y hydrom orphic soil and cu m u la tiv e y ie ld s od w h e a t (str a w + g r a in )
proved. The results presented in this form can be of use in designing drainage reclamations, indicating, among other things, optimum ground w ater table depths for the soil under consideration and for w inter wheat.
In case of plough soil form ation and difficult penetration of plant roots into the genetic В horizon the w heat grow th conditions are wor sening. It is illustrated in Fig. 7, in which sim ulated actual yields for
F ig. 7. S im u la ted a ctu a l y ie ld s for th e rootin g depth a s in F ig. 2 (upper line) and for that lim ited to 50 cm (low er lin e) fo r w in te r w h e a t cu ltiv a ted on h ea v y
260 P. K o w a lik
a norm al penetration of roots (as in Fig. 2) are shown as an upper line and the yields obtained in case when the root penetration is lim ited to the depth of 50 cm — as a lower line.
R EFERENCES
[1] B r a n d y k T., J a g o d z i ń s k i T., K o w a l i k P., T r z e c i e c k i E. : U se of th e b iom ass in crem en t sim u la tio n m odel for fo reca stin g y ie ld s from g ra s slan d s in th e Ż u ła w y coastal m arsh lan d region. W iad. IM UZ 14, 1981, 2, 125-145. [2] B r a n d y k T., K o w a l i k P., T r z e c i e c k i E. : A tte m p t of m o d ellin g
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Yield prognosis in BIGLEB system 261
sim u lta n eo u sly op eratin g grow th factors. Proc. 7th Intern. C oll. on P la n t A n a ly sis and F ertilizer P rob lem s, H an n over, Sep tem b . 1974, 473-503.
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p . KOW ALIK
SY STE M PR O G N O Z O W A N IA PLO NÓ W P o litech n ik a G dańska
S t r e s z c z e n i e
O pracow any program p rogn ozow an ia p lo n ó w p ozw ala sy m u lo w a ć d yn am ik ę u w ilg o tn ie n ia d ow oln ego rep rezen ta ty w n eg o p rofilu g leb o w eg o oraz p o ten cja ln e i a k tu a ln e p lo n o w a n ie roślin, u za leżn io n e od a k tu a ln ej tran sp iracji. D ane n iezb ęd ne do w y k o n a n ia ob liczeń ob ejm u ją w y n ik i stan d ard ow ych ob serw acji m eteo ro lo g iczn y ch (opady, tem p eratu ra, i w ilg o tn o ść w zg lęd n a p ow ietrza, zach m u rzen ie, p rędkość w iatru ) oraz p o d sta w o w e dane o w ła śc iw o śc ia c h fizy czn y ch gleb i roślin (reten cy jn o ść i p rzew od n ość w od n a g leb y , w y so k o ść roślin, głęb ok ość u k o rzen ie nia, p ok rycie g leb y roślin am i, w ra żliw o ść roślin na tem p eratu rę, m a k sy m a ln a e fe k ty w n o ść w y k o rzy sta n ia w o d y w prod u k cji roślin n ej).
P rogram y sy m u la cy jn e n a p isa n e są w języ k u FO R TR A N (Feddes i w sp.) [7] i d o sto so w a n e do p o lsk ich m a szy n liczą cy ch Odra 1305 oraz do sy stem u C Y BER 72. W ery fik a cja em p iryczn a m od elu została tu przep row ad zon a dla p szen icy ozim ej na ciężk iej g leb ie h yd rom orficzn ej.
P rzew id u je się, że przez szersze w y k o r z y sta n ie o p racow an ych program ów b ę dzie m o żliw e tw o rzen ie m ap p ro d u k ty w n o ści i urod zajn ości gleb dla w y b ra n y ch roślin w sk a źn ik o w y ch i dla różn ych typ ów , g a tu n k ó w i odm ian g leb w P olsce. Prof . d r P io t r K o w a l i k
I n s t y t u t H y d r o t e c h n i k i PG
