Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2009
Sammendrag
Bioforsk har i samarbeid med SLF og UMB utarbeidet en Tiltaksveileder for jordbrukspåvirka vassdrag. Den er et verktøy for kommuner og fylkesmenn i arbeidet med å gjennomføre EUs Rammedirektiv for vann i Norge.
Sammendrag
Det er ikke registrert sammendrag
Sammendrag
Published data of pH and conductivity in some acid humic waters have shown erroneous corresponding values. This means that the values were not consistent with each other according to well-recognized hydrochemistry. A main questions was arised in this connection. Were the measurements correct and if not which of them were wrong, pH, conductivity or both ? Assessment on basis of calculated and measured conductivity values, by using published data and own measurements, indicate primarily erroneous pH measurements. This makes the scientific papers which are based on these remarkable results partly of questionable value. Conductivity should generally act as a controlling parameter even if the latter also could have some uncertainties.
Sammendrag
Transport and turnover of dissolved organic carbon (DOC) is important in the C cycle of organic soils. The concentration of DOC in soil water is buffered by adsorption to the soil matrix, and has been hypothesized to depend on the pool size of adsorbed DOC. We have studied the effect of frequent artificial excessive leaching events on concentration and flux of DOC in shallow, organic rich mountain soils. Assuming a constant Kd value for DOC adsorption to the soil matrix, we used these data to assess the change in the pool of adsorbed (or potential) DOC in the soil. The study involved manipulation of precipitation amount and frequency in summer and autumn in small, heathland catchments at Storgama, southern Norway. The shallow soils (16 to 34 cm deep on average) limit the possibility for changes in water flow paths during events. The mini-catchments range in size from 75 m2 to 98 m2. Our data show that after leaching of about 1.2 g DOC m-2 the DOC concentration in runoff declines by approximately 50%. From this we conclude that the pool size of adsorbed potential DOC in the shallow soils at any time is of the order 2-3 g m-2. Frequent episodes suggest that the replenishment rate, which depends on the decomposition rate of soil organic matter, is fast and the potential DOC pool could be fully restored probably within days during summer, but with some more time required in autumn, due to lower temperatures. Both pool size of potential DOC and replenishment rate are seasonally dependent. The pool of potential DOC, and thus the DOC concentration in discharge, is at their maximum in the growing season. However, under non-leaching conditions, the concentration of DOC in soil water and thus the pool size of potential DOC seems to level off, possibly due to conversion of DOC to less reversibly bound forms, or to further decomposition to CO2.
Sammendrag
Colour has increased significantly in several Norwegian rivers and lakes over the past two - three decades (Haaland et al. 2007; de Wit et al. 2007). This has also been observed throughout Northern hemisphere (Forsberg and Petersen 1990; Freeman et al. 2001; Roulet and Moore 2006; Tranvik and Jansson 2002). The long term increase in colour has coincided with the decline in anthropogenic acid emissions which peaked in Europe around mid 1970s (Schöpp et al. 2003). During the earlier days of the acid rain history, Krug and Frink (1983) hypothesised that acid rain possibly could explain the previously reduced colour in lakes observed on the Northern hemisphere. The increase in colour and concentrations of organic carbon in lakes throughout the past decades have by several authors again been linked to the reduction of atmospheric acid emission, in the UK (Evans et al. 2006), in Norway (de Wit et al. 2007) and in northern Europe and northern America (Monteith et al. 2007).
Sammendrag
Side effects related to liming have been studied in four dimictic lakes (553-642 m a.s.l.; 59°57"N) in Finnemarka, a forested area in Southern Norway with poor catchment buffer capacity. Data series from lake profiles have been sampled two decades apart; 10 years prior to liming and after 10 years of liming. Water samples were collected during spring after ice breakup, and during summer after the development of thermal stratification. Before liming, there were very low concentrations of bicarbonate (HCO3-) (or alkalinity) in the lakes.After 10 years of liming, up to 90 % of the ions in hypolimnion originate from lime products. Hence; liming strengthened the chemical stratification and increased the vertical stability. Differences in chemocline developments between lakes were explained by differences in physical properties, i.e. their depth/surface area ratio. The chemocline developments lead to increased concentrations of organic matter in the hypolimnion, with a subsequent reduction in oxygen concentrations. Lime additions during late spring, as an alternative to early autumn, lead to pronounced anoxic conditions in the hypolimnion.
Sammendrag
Throughout the past few decades there has been a significant increase in TOC concentrations in several Norwegian lakes. Monitored lakes with limited or no buffer capacity (Chloride- and Sulphate-lakes), and especially the Sulphate-lakes (which have had a more pronounced decline in ionic strength related to the reduced anthropogenic acid components in precipitation), have had a significantly percentage increase in TOC concentrations throughout the past 15 yrs. Lakes with some buffer capacity (ANC-lakes) have not had a significant percentage increase in TOC concentrations throughout the same period.
Sammendrag
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Sammendrag
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Forfattere
Csilla FarkasSammendrag
The latest climate change scenarios, forecasting for the Tisza watershed valuable increase in the occurrence of extreme weather events as well as changes in land use policy increased the demand on knowledge towards sustainable flood plain and water reservoir management. The main objective of the present study was to develop an appropriate methodology that could be used for describing the soil water regime of the Bodrog Interfluve floodplain area at sub-regional scale and to derive the corresponding soil and hydrological database. This paper describes the fine-scale spatial soil database, constructed for characterizing the soil cover of the Hungarian territory of the Bodrog Region; the monitoring system, established in the study area and the mathematical modeling procedure carried out for better description of soil water regime and water balance elements. Further, performance and results of a scenario analyses are presented for evaluating the possible effects of two recently predicted climate change scenarios on soil water regime of a sensitive floodplain area. It was concluded, that based on the adaptation of a water balance simulation model and on the spatial soil physical database, the water regime of the dominant natural, semi-natural and agrarian ecosystems could be estimated. Compared to the present circumstances, the results of the scenarios analyses indicated more uneven and extreme surface and subsurface hydrological situations under changing climatic conditions.