Search results for "stream"
showing 10 items of 682 documents
Who Moves to Depressed Regions? An Analysis of Migration Streams in Finland in the 1990s
2002
Depressed regions typically lose a large number of migrants but simultaneously are destination regions for some migrants. This study analyzes those people who decided to move to depressed regions in Finland in 1993-1996. The analysis is based on a 1 percent sample drawn from the Finnish longitudinal census. The results show that migration into depressed regions is also a selective process. Return migration is only one part of this migration. However, the more educated an individual is, the more likely she or he is to move to a flourishing region. The process of concentration of human capital is reinforced by interregional migration.
La herida original de las políticas de inmigración : A propósito del lugar de los derechos humanos en las políticas de inmigración
2002
El artículo plantea algunas condiciones que permitan superar las dos posiciones en las que parece alternativamente preso el debate actual sobre la inmigración: la visión instrumental, torpemente pragmática, y la «humanitaria», anclada en la conmiseración o la piedad. Para alcanzar la dimensión política es preciso superar un análisis de los flujos migratorios erróneo, el que está en la base de ambas posiciones. Y si se supera esa visión, se superarán los actuales instrumentos jurídicos de política de inmigración, que no son acordes con el reconocimiento pleno y la garantía de los derechos humanos fundamentales, pero tampoco con el necesario reconocimiento de la condición de sujeto del espaci…
Vegetation as a tool in the interpretation of fluvial geomorphic processes and landforms
2016
Particularities of Grey Alder (Alnus incana) Stands in Riparian Galleries Along Streams of the Southern Transylvanian Tableland (Romania)
2019
Abstract Grey Alder (Alnus incana (L.) Moench.) stands are distributed in the Carpathian area on alluvial deposits with sediments of different grain size as galleries along rivers and streams of the sub-montane to the middle montane level. The geological structure (Tertiary sedimentary deposits) in relation to the hydromorphological processes is the base for the structure of the stream valleys, which are in part very deep. Under the special microclimate of these deeper stream stretches with lower temperatures there are favourable conditions for the development of grey alder stands.
The formation of alluvial fans and young floodplain deposits in the Lieser catchment, Eifel Mountains, western German Uplands: A study of soil erosio…
2011
This study deals with the exploration and spatiotemporal quantification of the young Holocene, nearly skeleton-free floodplain sediments of the Lieser River, a tributary of the Mosel River in the Eifel Mts. The deposits are primarily a consequence of anthropogenic-triggered soil erosion in the catchment. To observe the phenomenon of corresponding soil erosion on multiple levels two small alluvial fans of tributary catchments were investigated. For comparison, one location in the neighboring Salm valley was described. The results were compared with those of other streams. With extensive fieldwork more than 100 drillings and pits were made at 12 locations. For dating the sediments OSL dating…
Soil erosion susceptibility assessment and validation using a geostatistical multivariate approach: a test in southern Sicily
2008
A certain number of studies have been carried out in recent years that aim at developing and applying a model capable of assessing water erosion of soil. Some of these have tried to quantitatively evaluate the volumes of soil loss, while others have focused their efforts on the recognition of the areas most prone to water erosion processes. This article presents the results of a research whose objective was that of evaluating water erosion susceptibility in a Sicilian watershed: the Naro river basin. A geomorphological study was carried out to recognize the water erosion landforms and define a set of parameters expressing both the intensity of hydraulic forces and the resistance of rocks/so…
Climate change impacts on river runoff in Latvia
2011
In order to assess climate change impacts on river runoff patterns at the end of this cen- tury, the hydrological model METQ2007BDOPT was applied to 8 river basins and sub-basins in Latvia, which is a part of the southeast Baltic Sea basin. The climate data we used originate from the PRUDENCE project and were prepared in a separate study. Changes in hydro-climate were analysed using one control run (1961-1990) and 2 IPCC scenario runs (A2 and B2; 2071-2100). For the A2 sce- nario, both annual and seasonal analysis predicted the major significant changes in most cases. For both scenarios, an increase of the mean annual climate data (air temperature, precipitation and evapo - transpiration) i…
Modeling the Effects of Climate Change on Catchment Hydrology with the GWLF Model
2009
The influence of catchment hydrology on the volume and timing of water inputs to waterbodies, and on the material loads of nutrients, sediment, and pollutants is central to any assessment of the impact of climate change on lakes. Changes in the timing and amount of precipitation, particularly when coupled with a change in air temperature, influence all the major components of the hydrological cycle, including evapotranspiration, snow dynamics, soil moisture, groundwater storage, baseflow, surface runoff, and streamflow.
Experimental Modeling of Submerged Pivot Weir
2020
An inclined rectangular overflow structure, also called a pivot weir, consists of a rectangular plate, angled downstream from the vertical, that can be used as an upstream water level control device. A pivot weir is submerged when the upstream water level is influenced by the downstream flow depth. In this paper, to investigate factors influencing submerged flow conditions, an extensive experimental program including 251 experimental trials was carried out using weir inclination angles of 39.6°, 53°, 85°, and 90° and weir heights ranging from 0.263 to 0.312 m. A formula to distinguish between free and submerged flow conditions was developed using the Π theorem of dimensional analysis and th…
Application of the new multimetric MMI_PL index for biological water quality assessment in reference and human-impacted streams (Poland, the Slovak R…
2014
Abstract A new multimetric MMI_PL index, which is based on the macroinvertebrate composition and combines six single key metrics, has already been implemented in Poland according to the requirements of the EU Water Framework Directive. The objectives of our survey were to assess the biological water quality using the new multimetric MMI_PL index in both reference and human-impacted streams, to analyze whether the values of the new multimetric index properly reflect the ecological status of the water in upland and mountain streams as well as to determine which environmental factors influence the distribution of benthic macroinvertebrates and the values of the metrics. The study was carried o…