The peat landscapes of Holland: a matter of opportunities and challenges

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Text of The peat landscapes of Holland: a matter of opportunities and challenges

Dia 1

An overview of history & present situation

Sophie Visser

April 11, 2014

National Landscape Green Heart The peat landscapes of Holland:

A matter of opportunities and challenges

Peat lakes and meadows of Reeuwijk

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7500 BP Mainly tidal area 4750 BP - Coastal Barrier 1200 BP Middle Ages The Holocene as the basis: a quick overview (1)

Before the Reclamations: trees along the Old RhineFlood basin

Natural levees

+ depositsCrevasses and perimarine creeks

For the present-day landscapes in the western part of the Netherlands or better, Holland - , the Holocene is the important period. The important issue here are the deposits, evolution of the rivers and the development of the peat until about the year 1000, the start of the Mediaval reclamations in this part of Holland. Hence, some main phases from paleogeographic maps: 7500 BP: the fast rise of the sealevel, resulting in a tidal area with clay deposits and creeks 4750 BP: the closing of the coast barrier, behind which peat could develop and the rivers became meandering1200 BP: almost the situation at the start of the Mediaval reclamations

The meandering river will be well-known to you. The nice thingg in his picture was are the clear crevasses, the trees that were alo present along the Old Rhine, and the former rivers, layers and deposits beneath the surface. 2

MeijeAge of the channel belts (based on sedimentation):

former rivers : from 7200 BP onpresent rivers : until 800 BP

sea deposits (until 1000 BP)The Holocene as the basis: a quick overview (2) http://www.geo.uu.nl/fg/palaeogeography/Former and present rivers and sea clay deposition in this area

The picture of the former and present rivers in this area. The Holocene palaeogeographic development of the Rhine-Meuse delta was researched for over 40 years by Utrecht University.A geological-geomorphological map of the ages of the Holocene channel belts (scale 1:100,000) was published, together with palaeogeographic maps at 500 yr time intervals3

Brook peatland bog peatland The Peat Wilderness

The Holocene as the basis: a quick overview (3) Sphagnum peat not shown

Brook peats

Sedge peat

Reed peat

The development of the so-called Holland peat, which could become 6 meters high or more. At first reed peats developed in brackish eutrophic conditions. Gradually the nutrient influx (from the subsoil and by rivers/sea) in the peat bog dropped and mesotrophic (sedge) and oligotrophic (spagnum) peats accumulated. In the central parts of the peat bogs peat growth occurred under oligotrophic rain-water depended conditions. Under such conditions convex-shaped, high-lying, peat domes developed which had a natural drainage towards the river courses.Only close to the rivers, flowing through the bog, eutrophic conditions prevailed and brook peats were formed dominated by Alder. The large thickness of the peat (more than 5 m) can be explained by the gradual sea level rise after 5000 BP creating accommodation space for peat formation. 4

Hardly sphagnum peat or raised bog domes between Gouda and NieuwkoopThe Holocene as the basis: a quick overview (4) Growth of the peatover time

The general peat development in a cross section5

The Holocene as the basis: a quick overview (5) At the surface in the present

Generalisation of the soil map 1:50.000Soil map 1:10.000

The result of both is the generalized soil map that was included in the excursion map as well. At the left the sea clay at the surface of the droogmakerijen Middelburg and Tempel can be seen. The original peat (Holland Peat) has been excavated and the underlying marine Calais Deposits occur at the surface, including tidal creek patterns. At the left a detailed soil map !:10.000 of a part of Reeuwijk, including a part of the droogmakerij of Tempel. 6

Kade = low dikeSluis = sluice

Principle of peat reclamations: ditches, dikes, and drainageAfter cutting and burning the shrubs and trees .

Reclamation took place starting from the levees along the river courses (Lambert, 1971). These higher-lying somewhat better-drained levees were the access routes through the otherwise inaccessible peat bogs. Man reclaimed the dome-shaped peat bogs by natural draining through ditching. The low and small dikes at the side and the back consisted of peat from the ditches, hence many roads in the peat areas still mainly or partly consist of peat.

Reclamation occurred in a large-scale, well-organized manner resulting in a very regular structure of narrow (c. 110 m), but long (c. 1250 m) parcels perpendicular to the reclamation axis (levee) and extending into the former peat bogs.

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South of the Old Rhine (1): the early reclamations

Count of HollandBishop of Utrecht

The year 944:Rights to the wildernessgranted to Count andBishop by German Emperor

Border Count Bishop around 1100

Mound, stronghold

8The reclamations could start because in 944 the Bishop of Utrecht and Count of Holland got permission from the German Emperor to make use of the wilderness.The bishop started his reclamations from east of this area, the count west. From about 1100 this area became part of the border area of the two land lord, with many conflicts and fights and the building of a kind of mounds or strongholds.

At first he parcellation on the river banks had the shape of small irregular blocks - which still exist at some locations - but most of it has been replaced by peat-like parcellation.

South of the Old Rhine (2): all reclamations by about 1300

A variation in shapes and sizes!All reclamations needed permission from the land lord, either the Count of Holland or the Bishop of Utrecht. It was beneficial to both parties: the colonists became free men (no feudality any more, except in Tempel!), and the land lord expanded his jurisdiction and his income. Some reclamations were more organized than others. In that case, a group of colonists signed a contract ( a 'cope') with the landlord, and had to comply to a depth of the reclamation of about 1200 meters, leading to the 'cope ontginningen'. In Reeuwijk, from the direction of the parcellations, all forms and sizes of reclamations can be noticed

Settlements in peat reclamations lines of farms ('boerderijenlinten') alongside the bases of the reclamations (or some dike and/or watercourse thereafter, like in Bloemendaal, next to Gouda). Therefore, there were no buildings parallel to the ditches (as there are today). Some settlements were also allowed to build a small church. The picture shows how a former mound or stronghold looks today.All reclamations needed permission from the land lord, either the Count of Holland or the Bishop of Utrecht. It was beneficial to both parties: the colonists became free men (no feudality any more, except in Tempel!), and the land lord expanded his jurisdiction and his income. Some reclamations were more organized than others. In that case, a group of colonists signed a contract ( a 'cope') with the landlord, and had to comply to a depth of the reclamation of about 1250 meters, leading to the 'cope ontginningen'. 9

South of the Old Rhine (2): all reclamations

Few Cope- ontginningen, but

-Based on fixed depth?Based on known contract?

. 10

After the reclamations: subsidence => to peat meadows and peat lakes Arable land: rye, grain, hemp

Grassland, moderate dry, hay

Grassland, rather wet

Turf, peat lakes

PeatGroundwater level Drained peat

Initially the drainage was so efficient that the drained peat bogs were used as arable land (rye, barley, flax, hemp).However, due to the drainage and hence the shrinkage and oxidation of the peat the land surface dropped and arable land was replaced by meadows. This was partly the reason for the peat digging. Furthermore, the bog domes north of Nieuwkoop and west of the Gouwe with their sphagnum peat were less fertile and gave better turf for fuel. Hence, the biggest excavations were there.11

The resulting landscape: idyllic or .Roelofs, circa 1865

Agriculture started as mixed farming, including growing grain. But because of the drainage and hence the shrinkage and oxidation of the peat, the peat land got lower and lower en in the 15th century growing grain became a problem. Although farmers also started to grow hemp and flax, dairy farming became the main type of agriculture from that time on.

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Paul Gabril 1890Peat dredging > 1530,on an educative illustration desolate and poor?

The landscape in peat digging area, however, could be very desolate. Furthermore, people in those areas became very poor. However, where the lakes stayed on, in the 20th century they become popular for their watersports and nature and the former small fishermans and labourers houses become more and more replaced by big villas.

This large-scale peat digging was the result of the invention of a tool for dredging from under the water about 1530 called the dydle - , while at the same time the agriculture on the subsiding peat land was becoming more problematic and the need for fuel in the cities and in e.g. brick factories and breweries got higher.. The educational picture shows the different steps in the peat digging process: dredging of the peat, trampling, cutting in blocks, drying in piles and barns.

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Map of droogmaking Tempel e.o. 1734:should be finished in 1784, final permission in 1874

About 1900South of the Old Rhine (3): the droogmakerij of Tempel

Some of the peat digging plans had to comply from the start to droogmaking afterwards, especially from the