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Water reservoirs, as an element of small water retention, play an essential role in increasing the quantity of retained water as well as in extension of time and paths of its circulation in an agricultural landscape. One of possible ways to realize this aim is utilization of small reservoirs as a „water store" of drainage outflows. The method of ponds land reclamation importance valorization is presented in this paper. Following factors were considered as the criteria of an evaluation: reservoir surface area, its morphology, connection with hydrographic net, character of water structures (e.g. dams) and periodicity of water reservoir occurrence. The results of our research unambiguously indicated considerable drainage usefulness of water reservoirs to foregoing introduced aims. Drainage outflow water retention in water reservoirs will enable 100-150% increase of retained water quantity. It is a vital work, for the studied catchment area is situated in a region of the largest water deficits in Poland.
Małe zbiorniki wód powierzchniowych spełniają w krajobrazach rolniczych wiele istotnych funkcji: przyrodniczych, hydrologicznych i gospodarczych. Podlegają jednakże silnej antropopresji prowadzącej do ich degradacji ilościowej i jakościowej. Badania inwentaryzacyjne i waloryzacyjne zbiorników wodnych umożliwiają wytypowanie najbardziej wartościowych obiektów, które powinny zostać objęte ochroną prawną w formie użytków ekologicznych. Odpowiednio zorganizowany system zachęt umożliwić może ochronę i rozbudowę zarówno zbiorników wodnych jak i otaczających je barier biogeochemicznych spełniających funkcje ochronne. Czynną ochronę zbiorników wodnych w krajobrazach rolniczych można zapewnić poprzez wykorzystanie ich jako odbiorników wód drenarskich. Działania te, mieszczące się w ramach tzw. małej retencji, zapewniają poprawę stosunków wodnych na obszarach występowania największych deficytów wodnych w kraju.
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Biases in methane chamber measurements in peatlands

100%
The paper presents results of CH4 emission measurements at peatland with the application of the dynamic chamber technique. The measurements were conducted in two types of chambers differing in shape, height, volume and technology used to assure their tightness. The study tested how the following factors: 1) forced chamber headspace mixing or its absence, 2) mistakes of the person conducting measurements, 3) improper application of linear technique for calculating CH4 fluxes, and 4) simulated air sampling typical for static chambers, influence the significance of errors and the underestimation rate of CH4 fluxes measured in situ. It was indicated that chamber headspace mixing allows estimating methane fluxes with a smaller error than in the case of measurements conducted without mixing, and CH4 fluxes in such conditions can be 47 to 58% higher (depending on the chamber type) than in a chamber without fans. Using dynamic chambers and a fast analyzer to measure methane fluxes allows shortening the methane measurement process to a few minutes. On the other hand, using static chambers for methane flux measurements may lead to 70% underestimation of the calculated flux.
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Ekosystemy wodne obszarow wiejskich

63%
The multifunctional role of aquatic ecosystems on rural areas was analyzed and described in this paper. Among the most important issues this article discussed the water cycling and energy flow in aquatic ecosystems, their influence onto agricultural landscape biodiversity development and their role as biogeochemical barriers. Finally, the main principles of aquatic ecosystems protection were presented. The structure of heat balance of water ecosystems is similar to shelterbelts. Aquatic ecosystems intensify the process of evaporation and what is more, the smaller area of pond the bigger evaporation. Despite potential looses of water, it was proved that water ecosystems can be used to water (drainage) outtlow retention, and in this way they allow to increase the useful water capacity in the catchment area. Aquatic ecosystems and plants which are at the edge of them play an important role as biogeochemical barriers. They control the migration of non-point agricultural pollution. Moreover, small aquatic ecosystems of country area are mentioned to be the richest as regards the number of flora and fauna species. They influence onto biological diversity and species richness of, not only the water niche, but also the surrounding areas. That is why, they have to be protected. Among the protection guidelines, the principles of flora and fauna as well as water quality and water resources protection and renaturization of degraded ecosystems were described.
Small midfield ponds play in agricultural landscape important functions: natural, hydrological and economical. However, they are exposed to very strong anthropogenic impact. Valorization research of water ponds enables to point out the most valuable objects, which should be protected by law, for example as ecological sites. Active protection of water ponds in agricultural landscape is possible by using them to drainage water retention. The methods of ecological and land reclamation valorization of small ponds are presented in this paper. An ecological valorization of small ponds was based on: pond area, hydrography, pond flora, coastal zone, pond shelterbelts, land use around pond, and anthropogenic impact. Land reclamation usefulness was evaluated on the basis of: pond area, morphology, hydrography, dam building and periodic occurrence of small ponds.
Small water reservoirs play many important natural, hydrological and economical functions in the agricultural landscape. They are subjected to very strong anthropogenic pressure, leading to their quantita­tive and qualitative degradation. A classification proposal for small water reservoirs in an agriculturals from a deterioration point of view is presented in this paper. Classification is based on analysis of the following phenomena and processes: drainage, sewage drops, landfills, cattle pasturage, fish farming, fishing, tress and shrubs cut out as well as bordering on urban areas, country roads, landfill sites or cultivated fields. Four classes of anthropogenic impact were distinguished. Reservoirs free from any anthropogenic impact constitute the first class.
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