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V. Land Use and Productivity

V. Land Use and Productivity

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363



SOILS AND LAND USE IN THE NETHERLANDS



fluenced by the interplay of these two factors. A rotation often applied

in clay districts was: ( 1 ) fallow, with manuring for structure improvement; ( 2 ) colza or winter rape (the chief crop of that time); ( 3 ) barley

or wheat; ( 4 ) field beans (Vicin fnbn) for improvement of fertility; ( 5 )

wheat; ( 6 ) oats.

The fallow was gradually replaced by clover, and later such other

crops as potatoes, fiber flax, and sugar beets were introduced into the

rotation. A long rotation of this type has several advantages, the chief

of which perhaps are prevention of the establishment of diseases through

alternation of crops, and economy in the use of manure. After 1880 the

farmers made considerable use of fertilizers, and liming, too, became

the vogue.

At present, little is left of the old rotation discussed above. Fallow

land is a thing of the past, Market prospects now largely decide the

farmer’s choice of crops. Animal manure has given way to fertilizers

and the number of cattle has been greatly reduced. Soils are tested at

the Laboratory for Soil and Crop Testing, and the Extension Service is

prepared to give information about various diseases, proper fertilization,

and management of crops. It would seem almost as if the soil itself now

plays only a minor role in the production of many crops. This is largely

due to the progress made through agronomic research and the wide

diffusion of the results through educational programs for the farmers.

With proper management quite different kinds of soils may give similar

yields.

In Table VIII are given yields on heavy sea clay in the Oldambt in

TABLE VIII

Representative Yields of Crops on Two Very Different Types

of Soil in 1955

“Dollard”

heavy clay

(yield in tons/ha.)



Reclaimed high

peat “dal” soil

(yield in tons/ha:)



4.1

3.1

4.3

23

39



3.7

3.1

3.B

28

39



~



Spring wheat

Rye

Oats

Potatoes

Sugar beets



the province of Groningen, which is a naturally rich soil, and on “dalgrond,” a naturally poor soil derived from sand and moss peat. These

yields were representative of crops in 1955, which was a favorable season. In Table IX are given average yields of crops in other areas in the



364



P.



G. MEIJERS



TABLE IX

Representative Yields (tons per hectare) of Crops in Several Clay Areas in 1955



Winter wheat

Spring wheat

Spring barley

Oats

Green peas

Potatoes

Sugar beets



Zeeland



Northeastern

polder



Groningen

light

sea clay



Groningen

heavy

“Dollard” clay



3.8

3.7

3.9

3.5

3.8

29.2

48.9



4.0

4.0

3.8

4.5

3.6

28.5

48.0



4.1

4.1

3.8

4.4

2.8

25.0

41.0



3.6

4.1

3.7

4.3

2.8

23.0

39.0



same year. Where there are significant differences, these cannot be entirely explained.

Some soils are particularly suitable for special crops. Examples are:

caraway (Curium curoi) and colza (Brassicu nupus var. oleifem), which

grow best on rich and heavy clay. Sugar beets make a good crop on all

clay soils, but when grown on heavy clay, irregular germination and

difficult harvesting are drawbacks, Potatoes are best suited to light clay

because of the planting and digging operations. Fiber flax (Linum usitutissimum) is best on clay that is light or only moderately heavy, where

it comes up more uniformly and where the fertility of the soils is not so

high that rank growth occurs.



B. CURRENT

USE

The general characteristics of the major soils of the Netherlands are

summarized in Table X. It will be recognized that the use made of these

soils depends to a considerable degree on local economic considerations.

In Table XI the distribution of various crops is given as percentage of

the total land of each group of soils in cultivation. It is evident that there

is more crop diversification on sea clay than on soils of the other groups.

The acreage of cereals on sea clay is smaller but this, however, varies

greatly from district to district. For example, in Zeeland, only 35 per

cent of the sea clay soils are in cereals whereas in Groningen, the figure

amounts at present to 60 per cent because of the proximity of strawboard factories. Sugar beets are grown mainly on clay, mangolds on river

clay and sandy soils where they are used in cattle feeding. Potatoes are

grown everywhere but especially on high-peat soils for the starch industry.

One may alternatively examine the contribution made by the soils of



365



SOILS AND LAND USE IN THE NETHERLANDS



TABLE X

Summary of the Characteristics of the Major Soils in the Netherlands

Soil

characteristics

Inorganic

colloids



Sea clay



River clay



Sandy soils



High-peat soils



Rich



Rich



Poor



Poor



Organir mlat,trr Poor



Poor



Slight to

moderate



Rich



Reserve of

nutrients



Large



Moderate (often Small

potaRh fixation)



Water-holdiiig

oapaci ty



Good, not

sensitivc to

drought



Partly good,

partly sensitive

to drought



Low soils good;

high soils sensitive to drought



Favorable, not

sensitive to

to drought



Workability



Variable



Not as good us

sea clay



Eally



Easy



Productivity



Good, stable,

Moderate to

High, stable,

ample choice of ample choice of good, less stable,

crops with mod- crops with mod- limited choice

of crops with

erate amounts

erate amounts

regular heavy

of fertilizers

of fertilizers

fertilization



Small



Good, fairly

stable, limited

choice of crops

with regular

heavy fertilization



different origins to the total production of the major crops (Table XII).

It will be readily seen that the production of many crops on the sea clay

soils outweighs that on all others.

Seasonal climatic differences are larger on some soils than on others.

In Table XI11 are given average yields of some major crops in 1955 and

1956. The year 1955 was a favorable one with a dry period at harvest

time, whereas 1956 was wet and cold, especially at harvest. It will be

seen that in these two years cereals were the crops least affected, and

TABLE XI

Area of Crops Planted as Per Cent of Cultivated Land of Each Soil Group

Crop

Cereals

Green peas

Potatoes

Sugar beets

Mangolds



Sea clay



42

10

13

.5

12.

3



River clay



Sandy soil



60

3



70

1



10



15



8

12



3



7



High-peat soil

60

0.3

30

6

1.5



366



P. G. MEIJERS



TABLE XI1

Distribution of Total Production among Soil Groups"

Crop



Sea clay



Wheat

Rye

Barley

Oats

Pulse

Fiber flax

Potatoes for consumption

Industrial potatoes

Sugar beets

0



River clay



Sandy soil



High-peat soil



6

79

11

50

4

2

38

36

14



8

9

2



71

3

70

24

88

95

47

9

70



14



0

0

2

55

5



In per cent of weight (mass) per crop.

TABLE XI11



Comparison of Average Yields in Tons per Hectare of Some Crops, 1955 and 1956

Sea clay



River clay



Sandy soil



High-peat soils



Crop



1955



1956



1955



1956



1955



1956



1955



1956



Cereals

Green peas

Potatoes

Sugar beets



4.0

3.2

28

47



3.8

2.2

27

39



3.5

3.0

26

41



3.2

1.3

23

35



3.1

2.5

26

37



2.9

1.5

22

31



3.3



2.9



-



28

38



-



22

30



peas showed the greatest differences. Sugar beets also are responsive to

wet and cold weather. Of the various soils those from sea clay are less

affected by fluctuations in the weather.

There has been a steady increase in the yields of all crops in the last

half century (Table XIV). Statistics are not available for comparison of

TABLE XIV

Increase in Crop Yields in the Netherlands from 1890 to 1957

(Verslag over de Landbouw)

Years



Winter wheat

(kg./ha.)



Rye

(kg./ha.)



Oats

(kg./ha.)



Potatoes

(tonslha.)



1891-1900

1901-1910

1911-1920

1921-1930

1931-1940

1946-1950

1951-1957



1870

2200

2470

2910

3060

3460

3940



1510

1690

1760

2050

2260

2220

2840



1940

2200

2050

2070

2370

2500

3220



12.3

15.4

16.7

19.3

23.4

25.4



-



Sugarbeets

(tons/ha.)

30.1

30.4

30.5

33.0

37.6

39.6

41.0



367



SOILS AND LAND USE IN THE NETHERLANDS



these figures on the different groups of soils, but it is quite apparent that

yields everywhere have increased as a result of progress in agronomic

research and of educational programs reaching farmers.

In parallel with the increased yields of harvested crops, grassland is

similarly becoming much more productive. This can best be expressed

in terms of the number of cattle supported. In recent years the figure

for the number of milk cows was 110 to 115 per 100 ha. If one adds, in

addition, the young cattle and other livestock, such as horses and sheep,

one arrives at the equivalent of 200 milk cows per 100 ha. In areas of

intensive grassland farming this may even reach 250.



C. EDUCATIONAL

AND ADVISORY

SERVICES

After the great agricultural depression of 1880 to 1895, it was realized

that, for the welfare of the country, agricultural science must support

and enrich farm practice and that farmers must be informed as to the

requirements of good husbandry. A government extension service was

set up and agricultural colleges were founded, at first only in a few

places but later in almost every center of agricultural importance. In this

way efficient agronomic methods are made known to the farmers. The

agricultural research and extension activities in the Netherlands are not

inferior to those of other Western countries.

The scale of agricultural education in the Netherlands may be measured by the average number (per year) of pupils receiving instruction

in recent years :

Undergraduates at the Agricultural University

Pupils of agricultural and horticultural schools

Students attending various organized classes



800

26,000



34,000



The government extension service also brings economic and technical information to farmers by word of mouth, by published papers, and

by demonstrations. Extension service personnel play an important part

in essential research work. Thousands of field plots are set out annually

to test varieties, fertilizer rates, disease control, etc. This has the great

advantage that the extension service staff can speak from direct experience and can understand and evaluate the more basic work carried out

at a higher level.

The organization of the extension service recognizes subdivisions such

as agriculture, animal husbandry, horticulture and forestry. As a rule, for

the sector agriculture, each province of the country is divided into two

districts, each under an advisory agricultural expert assisted by a staff

of specialists. One of the specialists is generally an agronomist. Each

of the two districts is further subdivided into 10 to 20 areas; in each area



368



P. G. MEIJERS



is an assistant previously trained at a secondary agricultural college. This

man works directly with the farmers and depends on his own experience

in normal circumstances. When problems arise, he may invoke the help

of the specialist, who can in turn, if necessary, consult with experts in

the research institutes. Every area assistant is responsible for 300 to

600 farmers. The advice given is gratis. It is not possible to pay each and

every farmer an annual visit, and it is still a matter of dispute whether the

extension service should be expanded so as to make this possible. An intensive service of this type on a national basis entails great expense, and

there is, therefore, some reluctance to embark on a larger program.



REFERENCES

Edelman, C. H. 1950. “Soils of the Netherlands.” North Holland Publ., Amsterdam.

Directie van de Landbouw. 1913. “De Nederlandse Landbouw in het tijdvak 18131913.” Gebr. v. Langenhuysen, ’S Gravenhage.

Henkens, Ch. H. 1958a. Neth. J . Agr. Sci. 6 ( 3 ) , 183-190.

Henkens, Ch. H. 195813. Neth. J. Agr. Sci. 6 ( 3 ) , 191-203.

Hudig, J,, and Meijer, C. 1919. Verslag. Landbouwk. Onderzoek Rijkslandbouwproefsta. 23, 1-39.

Meijers, P. G. 1958. “Bijzondere Plantenteelt.” J. B. Wolters, Groningen.

Ministerie van Landbouw, Visserij en Voedselvoorziening. 1958. “Verslag over de

Landbouw in Nederland over 1956.” (Annual reports with a summary in

English. ) Staatsdrukkerij en Uitgeversbedrijf, ’s Gravenhage.

Mulder, E. G. 1938. “Over de betekenis van koper voor de groei van planten en

microorganismen.” Thesis, Wageningen.

Schuffelen, A. C., and vander Marel, H. W. 1955. Potassium Symposium, Rome,

1955, pp. 157-201.

Sneller, Z. W. 1951. “Geschiedenis van de Nederlandse Landbouw 1795-1940.” J. B.

Wolters, Groningen.



EFFECT O F NITROGEN ON THE AVAILABILITY O F SOIL

A N D FERTILIZER PHOSPHORUS T O PLANTS

D. L. Grunes

U. S. Northern Great Plains Field Station, United Stater Deparfment



of Agriculture, Mandon, North Dakota



I. Introduction . . . . . . . . . . . . . . .

11. Effects of Nitrogen on the Availability of Phosphorus to Plants .

A. Biological Effects . . . . . . . . . . . .

1. Root Area and Absorbing Capacity . . . . . .

2. Root Efficiency

3. Ammonium Ion Effect

. . . . . . . . .

4. Stage of Growth-Plant Nutrient Uptake Functions .

5. Effect of Nitrogen on Plant Metabolism and on Ability

to Absorb Phosphorus . . . . . . . . . .

B. Chemical Effects . . . . . . . . . . . .

1. Salt Effects

2. pH Effects

1II.Summary. . . . . . . . . . . . . . . .

References . . . . . . . . . . . . . . .



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Page

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. 370



. 370

370

. . . 372

. . . 377

. . . 378

of Roots

. . . 381

. . . 385

. . . 385

. . . 389

. . . 393

. . . 393



. . .



1. introduction



Various workers have found that the addition of nitrogen has affected

the uptake of soil and fertilizer phosphorus by plants. The effect of nitrogen on phosphorus availability has been studied by various techniques

and from various standpoints such as: effect on harvest yields (Chapman, 1936; Davis, 1938; Lorenz and Johnson, 1953); phosphorus concentration and total phosphorus absorbed by plants (Arnon, 1939; Breon

et al., 1944; Bennet et al., 1953; Domby et al., 1951; Glover, 1953a,b;

Goodall and Gregory, 1947; Grunes and Krantz, 1958; Krantz and Chandler, 1951; Lorenz, 1944; Luders, 1955; Prince, 1954; J. S . Russell et al.,

1954; Smith et al., 1950, 1951; Viets et al., 1954; Volk, 1944); relative

amounts of soil and fertilizer phosphorus absorbed by plants (Dion et

al., 1949a,b; Fine et al., 1955; Grunes et al., 1958a,b; Haddock et al.,

1957; Miller and Ohlrogge, 1958; Mitchell et al., 1952; Ohlrogge et al.,

1957; Olson and Dreier, 1956a,b; Olson d al., 1956; Rennie and Mitchell,

369



370



D. L. GRUNES



1954; Rennie and Soper, 1958; Robertson ct al., 1954; Smith et aZ., 1951);

uptake of radioactive phosphorus (Yatazawa et al., 1953); and studies

of solubility effects on soil and fertilizer phosphorus (Bouldin and Sample, 1958; Buehrer, 1932; Olsen, 1953; Starostka and Hill, 1955). In this

paper an attempt will be made to review the literature and to analyze

some of the causes of the effect of nitrogen on the availability of soil

and fertilizer phosphorus to plants.

II. Effects of Nitrogen on the Availability of Phosphorus to Plants



The effects of nitrogen on the availability of phosphorus to plants

may be divided into biological effects and chemical effects. Biological

effects are those caused indirectly by the effects of nitrogen on the form

and functions of the plant, independently of any direct chemical effects

the applied nitrogen may have on the availability of the phosphorus

sources in the soil.



A. BIOLOGICAL

EFFECTS

1. Root Area and Absorbing Capacity

Since both nitrogen and phosphorus are elements essential for plant

growth, it would be expected that a deficiency of either element would

limit growth of the above- and below-ground portions of the plants. If

all other essential elements are supplied it would be expected that the

addition of nitrogen would stimulate root growth. Increased root growth

in the vicinity of a phosphorus fertilizer band should preferentially increase the absorption of fertilizer phosphorus, and stimulation of root

growth by placement of nitrogen away from a band of phosphorus fertilizer should preferentially increase the absorption of soil phosphorus.

Working with split-root techniques in culture solutions, Gile and

Carrero (1917) reported that the weight of corn and rice roots was

greater in the solutions containing nitrogen.

Grunes et al. (1958b) found in a growth chamber that the addition

of ammonium sulfate generally increased the relative amount of barley

roots in the vicinity of a band of concentrated superphosphate. They

believed that this was one of the reasons why banding nitrogen and

phosphorus fertilizers together increased the percentage of the plant

phosphorus absorbed from the fertilizer. Although placement of ammonium sulfate fertilizer in a band on the opposite side of the barley

plants from the phosphorus fertilizer band increased the total weight

of barley roots produced by the plants, the proportion of roots in the

phosphorus fertilizer band was generally similar to that when no nitro-



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