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V. Land Use and Productivity
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
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
In Table VIII are given yields on heavy sea clay in the Oldambt in
Representative Yields of Crops on Two Very Different Types
of Soil in 1955
(yield in tons/ha.)
peat “dal” soil
(yield in tons/ha:)
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
Representative Yields (tons per hectare) of Crops in Several Clay Areas in 1955
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.
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
SOILS AND LAND USE IN THE NETHERLANDS
Summary of the Characteristics of the Major Soils in the Netherlands
Organir mlat,trr Poor
Moderate (often Small
Low soils good;
high soils sensitive to drought
Not as good us
ample choice of ample choice of good, less stable,
crops with mod- crops with mod- limited choice
of crops with
choice of crops
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
Area of Crops Planted as Per Cent of Cultivated Land of Each Soil Group
P. G. MEIJERS
Distribution of Total Production among Soil Groups"
Potatoes for consumption
In per cent of weight (mass) per crop.
Comparison of Average Yields in Tons per Hectare of Some Crops, 1955 and 1956
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
Increase in Crop Yields in the Netherlands from 1890 to 1957
(Verslag over de Landbouw)
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.
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
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
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.
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.
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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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,
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.
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-