The soils of the blies valley near Reinheim were mapped from the floodplain and hillsides up to the plateau. Furthermore 6 profiles in the floodplain have been recorded.

On the plateau exist in the middle trias ("Oberer Muschelkalk") rendzic leptosols and stagnic luvisols. These soils are eutrophic, but the high content of clay and limestone makes them hard to cultivate.
In areas exposed to erosion, especially at steep slopes, rendzic leptosols dominate. The soil depth decreases here to 16 cm. In spite of their high erosion rate these eutrophic soils have been cultivated. Today agriculture in this area makes no economic sense due to the high rate of soil degradation.
In the middle of the slopes, the transition from "Oberer" to "Mittlerer Muschelkalk", stagnic luvisols and eutric vertisols are present. On the marls of "Mittlerem Muschelkalk" often spring horizons develop and the soils are poorly drained.
On the more gentle slopes below deep colluviums occur. In these regions soil material removed from the acres above is deposited. Their depth reflect the high rate of erosion. The displacement of soil material resulted in a conspicuous change of the relief, for example the more gentle slopes in the lower parts of the slopes.
In the area around the bend of the Blies near Reinheim these colluviums are lacking  in the corresponding areas. Instead of the soil sediments to be expected on gravel terraces young eutric cambisols and gleyic cambisols are found developed in the material of an alluvial fan which is cut by the river. Besides fine soil material and rounded gravels particularly less or not rounded limestones appear indicating mudflow-like mass movements. The correlating erosion groove in the upper part of the slope west of Reinheim is wooded and therefore maintained, whereas the alluvial fan underneath has been adapted to the surrounding relief by ploughing. Where the fan is still obvious in the ground, it covers the A- and B-terraces of the river Blies which implies that the fan is younger than the river terraces of the last ice age. The dimension of the fan gives reasons for the assumption that the course of the Blies was changed at this point by the alluvial fan.
 

Depth in cm under recent surface	sketch	Name of Horizon	description	date
0-25	x  x x x x x x	Ap	silty-loamy sand, colour 7.5YR4/2, humous with clay lenses, pieces of limestone and splinters of bricks	post-roman, probably medieval or modern time
25-45	x  x x	M1	silty-loamy sand, colour 7.5YR4/3, splinter of bricks and charcoal, solid	post-roman, probably medieval or modern time
45-61	x x  x x	fAp/ M2	sand,  sligthly loamy, colour  5YR5/4, roman and pre- historian finds	pre- and synroman probably roman ploughing horizon
61-65			charcoal band
65-80		CI	sligthly loamy sand, colour 5YR5/4, bleach zones (clay displacement?)	sedimentation in phases
80-95	==============================	CII/Bt	sligthly loamy sand, colour 5YR5/6, intense rusty spots, clay bands	near to
95-103	OOOOOOOOOOOOOOOO		gravel band, (rounded and subangular up to 5 mm)	the Blies
103-110			charcoal band
110-122		CIII	sand, colour 5YR6/4	early holocene
>122	OOOOOOOO OOOOOOOO OOOOOOOO	CIV	terrace gravels (rounded and subangular up to 6 cm) in sand	ausgehende Würm-Eiszeit

Profile sketch 2 as example for the soils in the investigation area

As a result of the mapping the soil types in the floodplain can be divided into two different groups. On the Würm glacial A-terrace in the area of episodic flooding eutric fluvisols developed whereas in the area of recent flooding also eutric gleysols are found. The soils of the lower parts are strongly influenced by groundwater and innundated annually.
The base in 120/125 cm depth is built of gravels from the Würm Ice Age. The gravels (up to 5 cm, rounded and subangular) were accumulated in the braided riverbed of the Blies during the last Ice Age. For lack on supply of coarse debris masses after the last ice age fine and sandy material was deposited on the river banks. The river Blies incised in its sediments and the riverbed got fixed.
The investigation area is located on a sand accumulation overlying gravels near the river bank. This situation is reflected in the profile by a 15-20 thick sand layer on up to 6 cm big rounded gravels in sandy material. Within the sand layer up to 3 cm thick charcoal bands can be found. Due to the big charcoal remains (up to 3 cm) and its spatial sharp delimitation the band can be interpreted as fire layer. At some places the charcoal layer is covered by sand probably displaced from surrounding uncovered areas. Material from the knogs was so accumulated in the depressions of the micro relief. These layers are continously covered by a thin band of rounded and subangular gravels (5-7 cm) indicating the plain was formed by periodical flooding after the Ice Age.
Further thin gravel bands in western direction thin out in eastern direction probably marking the transition to the embankment.
After the Ice Age had finished and vegetation cover increased more fine material was sedimentated. The alternation of sand and gravel bands is a consequence of seasonal changes in river discharge. Due to the higher position of the terrace and therefore less flooding the gravel bands outcrop in the area further from the river Blies.
The gravels are covered by two horizons of sandy river sediments in a depth of 61/65-95/103 cm designated as CI and CII. The slightly loamy sand of CII shows significant hydromorphic features (marbling, rusty). At the base of CII in profile 1 clay bands in a depth of 100 cm developed by pedogenic clay displacement. A sedimentary genesis is excluded by its characteristics and the fact that the clay bands also traverse the pit filling and the surrounding bedrock. The horizon CII is followed above by loose, slightly loamy sand in a depth of 61/65 to 80 cm (CI). Sandy bleached zones indicate a loss of clay. CI differs from CII only by the rosty spots and the clay bands developed by pedogenic processes and now differentiating the originally uniform material.
In a depth of 60/65 cm sand- and gravellayers follow including another charcoalband and mesolithic finds. Mesolthic finds above CI but missing in layers beyond indicate the age of these layers to be between the end of the last Ice Age and about 11700 to 11000 bp.. This means that after the end of the Ice Age until about 11000/11700 bp. the plain still was regularly flooded and the sand banks were enlarged and heigthened. This layer is missing in the recent flood plain. From the Mesolithic the accumulated material decreases with increasing wood and vegetation cover.

Figure: Profile sketches of the 6 recorded profiles in the flood plain of the river Blies (for explanation see text). Profile 1 cuts probably a roman sand pit. In its filling (M2- material) roman and mesolithic finds occur. Profile 3 shows that the roman road is covered by M1. It is build in M2. Due to disturbances M2 is yet difficult to identify. Profiles 4-6, lying in one line from the river (profile 6 is the furthest from the river), illustrate the thinning-out of the small gravel bands with increasing distance from the river. This probably marks the ancient  embankment.

The several cm thick charcoal band ( with pieces up to 5 mm) at the top of CI can also be interpreted as a fire layer. The band is interrupted by a probably roman pit in profile 1. For this reason the top of C1 with the fire layer is supposed to be a pre-roman surface. The mesolithic finds are mixed up with younger finds in one layer which means the time between 11700/11000 bp and about 2000 bp was a time with low sedimentation and less surface changes. This is also confirmed by investigations of WEISROCK & FRANOUX(1993).
The CI horizon is covered from 45 to 61/65 cm by the M2 horizon developed in displaced soil material. The loamy sand is dense, humous with rests of charcoal and splinters of bricks which point to a roman age of the horizon. The mesolithic Ah eventually mixed with the M2. The relatively homogeneous character of M2 indicates a fossil ploughing horizon. The pit filling material in profile 1 also originates in the M2 horizon (see fig.). The top of the pit is at the same time the bottom of M2. According to that and the lack of CI-material in the pit, the pit was built in roman time after the deposition of CI.
Probably since roman time intensive erosion of soil material caused by clearing and agriculture started in the catchment area. This resulted in accumulation of humous displaced upper soil on top of the pre-roman surface. In this layer presumably a roman ploughing horizon evolved. Evidences for a fossil ploughing horizon are its homogeneous character, its thickness and mesolithic finds in this layer. The finds above the charcoalband assumed to date from stone age can be explained by ploughing them up. Finds from mesolithic to roman are also present in the M2-material in the pit. As many other pits in the area this pit was probably used in roman time for sand extraction. After abandonment upper soil material (M2) with the finds was washed into the pit.
Consequently the time between mesolithic and celtic/roman settlement is supposed to be without great geomorphological changes and without great flooding events. Because of the homogeneous character of the M2-layer it is most likely that the romans used the flood plain for agriculture. The soils in the flood plain offered ideal conditions for agriculture whereas the wooded slopes needed first to be cut as there certainly grew a mixed oak-hirnbeam forest. Furthermore the clayish soils of the Middle Trias are harder to treat. With cutting the forests on the hillsides soil erosion started and considerable masses of soil material have been displaced. This is proofed by thick colluviums at the bottom of the slopes, cut and degraded soils at the top of the slopes and a large fan at the end of a long groove in the slope southwest of Reinheim.
The large fan could have caused a shift in the course of the Blies. The unsorted fan material of soil material, big angular debris of Middle Trias and terrace gravels implies mud flow-like mass transports. The fan covers the B-terrace completely and the A-terrace partly which means it developed after the Ice Age. Furthermore A- and B-terraces follow the bow of the valley whereas the river changes remarkably its direction which is a further evidence for the post-glacial age of the river shift. A recent deep indicates the attempt of the Blies to flow again its original course.
Above the M2 horizon lies with a sharp border the M1 horizon (including the recent ploughing horizon Ap). The depth of the border varies very less in the whole area (see fig.) - also characterizing the upper horizons as ploughing horizons. The upper two horizons are much more cohesive than the horizons beyond as more frequent flooding in consequence of clearing and agriculture on the slopes accumulated first sandy material in the flood plain.
At the same time incision of the Blies started due to the higher discharge causing a reduction of the flow velocity during the floods as the area is flooded less. Finer, silty-clayey material sediments. Also the roman street (see fig.) and the rests of the nearby roman villa are covered up to 52 cm by these sediments. They are therefore dated post-roman. Probably they correlate to the medieval and modern erosion phases.
Due to agriculture for many years the Ap horizon reaches a medium depth of 25 cm. In parts not used for agriculture for long times a humous Ah-Horizon developed with parts of charcoal and splinters of bricks in a silty-loamy sand.

literature:
Weisrock, A., Franoux, D. (1993): L'environnement du site de Bliesbruck-Reinheim: étude du fond de vallée de la Blies. In: Blesa - Veröffentlichung des Europ. Kulturparks Bd 1, S. 223 - 235.

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