(Table 1) Cation exchange capacity and other characteristics of soils common in Lower Saxony, Germany

The chemical and biochemical processes associated with the filtration of rainwater through soils, a step in groundwater recharge, were investigated. Under simulated climatic conditions in the laboratory, undisturbed soil columns of partly loamy sands, sandy soils and loess were run as lysimeters. A series of extraction procedures was carried out to determine solid matter in unaltered rock materials and in soil horizons. Drainage water and moisture movement in the columns were analysed and traced respectively. The behaviour of soluble humic substance was investigated by percolation and suspension experiments. The development of seepage-water in the unsaturated zone is closely associated with the soil genetic processes. Determining autonomous chemical and physical parameters are mineral composition and grain size distribution in the original unconsolidated host rock and prevailing climatic conditions. They influence biological activity and transport of solids, dissolved matter and gases in the unsaturated zone. Humic substances, either as amorphous solid matter or as soluble humic acids play a part in diverse sorption, solution and precipitation processes.

Heavy metal concentrations in soils, vegetation, earthworms and wood mice from Heteren and Plateaux, The Netherlands

Effects of soil properties on the accumulation of metals to wood mice (Apodemus sylvaticus) were evaluated at two sites with different pH and organic matter content of the soil. pH and organic matter content significantly affected accumulation of Cd, Cu, Pb and Zn in earthworms and vegetation. For Cd, Cu and Zn these effects propagated through the food web to the wood mouse. Soil-to-kidney ratios differed between sites: Cd: 0.15 versus 3.52, Cu: 0.37 versus 1.30 and Zn: 0.33-0.83. This was confirmed in model calculations for Cd and Zn. Results indicate that total soil concentrations may be unsuitable indicators for risks that metals pose to wildlife. Furthermore, environmental managers may, unintentionally, change soil properties while taking specific environmental measures. In this way they may affect risks of metals to wildlife, even without changes in total soil concentrations.

Chemical composition and age of metamorphic rocks from the Khavyven Highland, Eastern Kamchatka

Metamorphic rocks of the Khavyven Highland in eastern Kamchatka were determined to comprise two complexes of metavolcanic rocks that have different ages and are associated with subordinate amounts of metasediments. The complex composing the lower part of the visible vertical section of the highland is dominated by leucocratic amphibole-mica (+/-garnet) and epidote-mica (+/-garnet) crystalline schists, whose protoliths were andesites and dacites and their high-K varieties of island-arc calc-alkaline series. The other complex composing the upper part of the vertical section consists of spilitized basaltoids transformed into epidote-amphibole and phengite-epidote-amphibole green schists, which form (together with quartzites, serpentinized peridotites, serpentinites, and gabbroids) a sea-margin ophiolitic association. High LILE concentrations, high K/La, Ba/Th, Th/Ta, and La/Nb ratios, deep Ta-Nb minima, and low (La/Yb)_N and high 87Sr/86Sr ratios of the crystalline schists of the lower unit are demonstrated to testify to their subduction nature and suggest that their protolithic volcanics were produced in the suprasubduction environment of the Ozernoi-Valaginskii (Achaivayam-Valaginskii) island volcanic arc of Campanian-Paleogene age. The green schists of the upper unit show features of depleted MOR tholeiitic melts and subduction melts, which cause the deep Ta-Nb minima, and low K/La and 87Sr/86Sr ratios suggesting that the green schists formed in a marginal basin in front of the Ozernoi-Valaginskaya island arc. Recently obtained K-Ar ages in the Khavyven Highland vary from 32.4 to 39.3 Ma and indicate that metamorphism of the protolithic rocks occurred in Eocene under effect of collision and accretion processes of the arc complexes of the Ozernoi-Valaginskii and Kronotskii island arcs with the Asian continent and the closure of forearc oceanic basins in front of them. The modern position of the collision suture that marks the fossil subduction zone of the Ozernoi-Valaginskii arc and is spatially restricted to the buried Khavyven uplift in the Central Kamchatka Depression characterized by well-pronounced linear gravity anomalies.

Organic carbon and total nitrogen stocks in soils of the Lena River Delta

The Lena River Delta, which is the largest delta in the Arctic, extends over an area of 32 000 km**2 and likely holds more than half of the entire soil organic carbon (SOC) mass stored in the seven major deltas in the northern permafrost regions. The geomorphic units of the Lena River Delta which were formed by true deltaic sedimentation processes are a Holocene river terrace and the active floodplains. Their mean SOC stocks for the upper 1 m of soils were estimated at 29 kg/m**2 ± 10 kg/m**2 and at 14 kg/m**2 ± 7 kg/m**2, respectively. For the depth of 1 m, the total SOC pool of the Holocene river terrace was estimated at 121 Tg ± 43 Tg, and the SOC pool of the active floodplains was estimated at 120 Tg ± 66 Tg. The mass of SOC stored within the observed seasonally thawed active layer was estimated at about 127 Tg assuming an average maximum active layer depth of 50 cm. The SOC mass which is stored in the perennially frozen ground at the increment 50-100 cm soil depth, which is currently excluded from intense biogeochemical exchange with the atmosphere, was estimated at 113 Tg. The mean nitrogen (N) stocks for the upper 1 m of soils were estimated at 1.2 kg/m**2 ± 0.4 kg/m**2 for the Holocene river terrace and at 0.9 kg/m**2 ± 0.4 kg/m**2 for the active floodplain levels, respectively. For the depth of 1 m, the total N pool of the river terrace was estimated at 4.8 Tg ± 1.5 Tg, and the total N pool of the floodplains was estimated at 7.7 Tg ± 3.6 Tg. Considering the projections for deepening of the seasonally thawed active layer up to 120 cm in the Lena River Delta region within the 21st century, these large carbon and nitrogen stocks could become increasingly available for decomposition and mineralization processes.

Analysis of soils from King George Island and Casey station, Antarctica

A comparative study was carried out on soils of the maritime (Arctowski, King George Island) and the continental (Casey, Wilkes Land) Antarctic. Soil sampIes are described for surface layers (0-10 cm) by their in situ temperature profiles as well as by field and laboratory analyses of grain sizes, pH and nutrient contents. Active cryoturbation is a main factor of mixing processes in surfaces with high silt and clay content. In both regions processes of podzolisation were recognized. Microclimatic conditions show the importance of small scale processes which are of special importance for freeze-thaw cycles. The distribution of nutrients and other inorganic components is rather homogeneous in regosols and leptosols. But in soils with organic top layers by lichen and moss cushions (crusts) accumulation occurs as well as displacement of metal ions into deeper layers (>10 cm). Histosols show patterns of brown soils. Special attention is given to the origin of nitrogen compounts and the different ways of import of other components (e.g. chloride) into the Antarctic system are discussed.