![]() Transport via shipping and dispersal via man made waterways are the most important dispersal vectors. Important donor areas are the Ponto-Caspian area and North America (44.4 and 26.7% of the non-indigenous macroinvertebrate species, respectively). The Delta Rhine and Upper Rhine exhibit higher numbers of non-indigenous species than other river sections, because the sea ports in the Delta Rhine and the Main-Danube canal function as invasion gateways. Currently, the contribution of non-indigenous species to the total species richness of macroinvertebrates in the river Rhine is 11.3%. The average number of invasions per decade shows a sharp increase from <1 to 13 species. From the eighteenth century onward, in the freshwater sections of the river Rhine, a total of 45 non-indigenous macroinvertebrate species have been recorded. The extensive network of inland waterways has allowed macroinvertebrate species from different bio-geographical regions to mix, changing communities, affecting the food webs and forming new constraints on the recovery of the native biodiversity. Six principal invasion corridors for aquatic species to the river Rhine are discerned. Over the last two centuries, the total surface area of river catchments connected to the river Rhine via inland waterways has been increased by a factor 21.6. This tendency has been accelerated by the construction of canals connecting river basins. Improving water quality while these constraints remain in place has led to increased colonization by aquatic invasive species. These constraints comprise intensive navigation and habitat modification by hydraulic engineering. German companies faced supply bottlenecks and production problems in 2018 from low Rhine water levels.The river Rhine is heavily influenced by human activities and suffers from a series of environmental constraints which hamper a complete recovery of biodiversity. The Rhine is an important shipping route for commodities including grains, chemicals, minerals, coal and oil products including heating oil. Navigation authorities do not close the river at times of low water, leaving it to vessel operators to decide when to stop. Low Rhine water will affect output over the coming month from two major German coal-fired power stations and could cause logistics problems for coal importers.Ĭhemicals group BASF (BASFn.DE) said on Friday it could not rule out production cuts if low water disrupts logistics. ![]() Hot and dry weather is forecast this week and no relief is in sight. Spot prices for transport in a liquid tanker barge from Rotterdam to Karlsruhe south of Kaub rose to about 110 euros a tonne on Wednesday, up 16 euros on Tuesday and up from only around 20 euros a tonne in June before water levels fell, traders said. But the number of vessels still capable of sailing in the shallow water, especially around Kaub, is declining so increasing transport costs for cargo owners, traders said. Vessels need about 1.5 metres of reference waterline to sail fully loaded.įreight shipping on the river continues, but with vessels sometimes forced to sail three-quarters empty. The reference waterline level at the chokepoint of Kaub south of Koblenz was at 48 centimetres on Wednesday, said Refinitiv Eikon data, down about 4 centimetres on the day. Shallow water after the summer heat-wave has hampered shipping on the entire river in Germany since July, along with other European waterways. HAMBURG, Aug 10 (Reuters) - Water levels on the river Rhine in Germany have fallen again in hot and dry weather and shipping costs are rising as vessels cut loads to continue sailing, commodity traders said on Wednesday.
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