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Analysis of control factors of the development of forest ecosystems at the higher altitudes of the Moravian-Silesian Beskids Mts. [Czech Republic]
1998
Kulhavy, J. | Klimo, E. | Hadas, P. (Mendelova Zemedelska a Lesnicka Univ., Brno (Czech Republic))
Evaluation of the water chemism during the flood wave of July 1997 in the Cervik and Mala Raztoka catchment areas in the Beskids Mts. [Czech Republic]
1998
Lochman, V. (Vyzkumny Ustav Lesniho Hospodarstvi a Myslivosti, Jiloviste-Strnady (Czech Republic)) | Chlebek, A. | Jarabac, M.
Biometrical relationships of volume increment to crown defoliation and other variables of spruce stands in the Oravska Polhora research site [Slovak Republic]
1998
Smelko, S. (Technicka Univ., Zvolen (Slovak Republic). Lesnicka Fakulta)
This contribution deals with the relationship evaluated on the basis of 32 permanent monitoring plots. Tree volume increment as a total "brutto" and also as a pure "netto" change for 1 ha is defined. The first one includes also the influence of felling, mortality and increment ingrowth, second one includes only changes due to the growth process. Relationship of increment to stand variables is investigated bz stepwise regression. A more higher correlation to defoliation was found, less high to age, site index and altitude.
Afficher plus [+] Moins [-]Investigation of the spruce stand radiation regime
1998
Tomaskova, K. (Mendelova Zemedelska a Lesnicka Univ., Brno (Czech Republic). Lesnicka a Drevarska Fakulta)
Radiation regime is the important part of the energy flow through the stand structure. The goal of the radiation regime studies in the forest stand is to create and develop the technology for radiation measurements and to estimate the impacts of stand density on the radiation regime. The experiment is carried out the Experimental research site Bily Kriz in the Moravian - Silesian Beskydy Mts. with a Norway spruce monocultural stand. Intensities of photosynthetic active radiation, global radiation and intensities of incident and transmitted photosynthetic active radiations through the stand were measured.
Afficher plus [+] Moins [-]Determination of rainfall-runoff flood hydrograph for small mountainous watersheds
1998
Byczkowski, A | Ignar, S. (Warsaw Agricultural Univ., Warszawa (Poland)) | Chlebek, A. | Jarabac, M.
The subject of the present study is application of the Wackermann conceptual rainfall-runoff model for rainfall flood hydrograph evaluation of small mountainous watersheds. A quasi-physical system concept for transformation of hydrological variables are used in this model. Effective rainfall was determined with the use of Soil Conservation Service method according to analysis of total rainfall and direct flow volumes. The Rosenbrock optimization method was adopted for determinig of model parameters using rainfall and runoff data recorded on the Mala Raztoka mountainous creek in the Moravian Beskid Range.
Afficher plus [+] Moins [-]Causes and consequences of mangrove deforestation in the Volta Estuary, Ghana: some recommendations for ecosystem rehabilitation.
1998
Rubin, J. A | Gordon, C. | Amatekpor, J. K.
The damming of the Volta River has resulted in reduced flooding and an increase in mangrove cutting, accompanied by the virtual collapse of agriculture and fishing in the estuary. Another ecological consequence of the reduced level of flooding has been reduced dispersal of seedlings of the principal mangrove, Rhizophora racemosa. Therefore, after cutting of this species, recolonization is either by conspecifics growing at very high densities or by one of a number of weed species, particularly Typha domingensis, Acrostichum aureum, Paspalum vaginatum, Cyperus articulatus, Sesuvium portulacastrum and Philoxerus vermicularis. Environmental data collected in the vicinity of the mangroves and each of the weed species have enabled suggestions to be made as to whether R. racemosa or Avicennia africana would be the more suitable mangrove to replant. Recommendations have also been made to introduce the palm Nypa fruticans to the area, together with the development of nature-based tourism, both of which would provide alternative means of income generation, thereby reducing the need to cut remaining mangroves.
Afficher plus [+] Moins [-]Drinking water supply and agricultural pollution
1998
Schrama, Geerten J. I.
Water pollution risks of methyl tertiary butyl ether (MTBE)
1998
Water pollution from agriculture in the context of land use planning
1998
Nishizawa, Eiichirō
Guidelines for evaluating air pollution impacts on wilderness within the Rocky Mountain region
1998
Haddow, Dennis | Blett, Tamara | Fisher, Richard | Musselman, Robert C.