Top PDF Decadal water balance of a temperate Scots pine forest (<i>Pinus sylvestris</i> L.) based on measurements and modelling

Decadal water balance of a temperate Scots pine forest (<i>Pinus sylvestris</i> L.) based on measurements and modelling

Decadal water balance of a temperate Scots pine forest (<i>Pinus sylvestris</i> L.) based on measurements and modelling

Aubinet, M., Grelle, A., Ibrom, A., Rannik, U., Moncrieff, J., Foken, T., Kowalski, A. S., Martin, P. H., Berbigier, P., Bernhofer, C., Clement, R., Elbers, J., Granier, A., Grunwald, T., Morgen- stern, K., Pilegaard, K., Rebmann, C., Snijders, W., Valentini, R., and Vesala, T.: Estimates of the annual net carbon and water exchange of forests: The EUROFLUX methodology, in: Advances in Ecol. Res., Vol. 30, Academic Press Inc, San Diego, 113–175, 2000.

37 Ler mais

Modelling short-term variability in carbon and water exchange in a temperate Scots pine forest

Modelling short-term variability in carbon and water exchange in a temperate Scots pine forest

Figure 10. Daily observed and modelled fluxes for GPP (a) and AET (b) for July and August in two different climate years. In summer 2003 a heatwave and corresponding drought occurred in Europe (e.g. see Teuling et al., 2010). Based on long term averages of the Dutch Royal Me- tereological Institute (KNMI), higher temperatures, more sunshine hours and much less precip- itation was received during this summer, and an official heatwave took place in the Netherlands during August (KNMI, 2003). The KNMI defines a heatwave as a period of at least 5 consec- utive days in which the maximum temperature exceeds 25 ◦ C, provided that on at least 3 days
Mostrar mais

49 Ler mais

Needle age-related and seasonal photosynthetic capacity variation is negligible for modelling yearly gas exchange of a sparse temperate Scots pine forest

Needle age-related and seasonal photosynthetic capacity variation is negligible for modelling yearly gas exchange of a sparse temperate Scots pine forest

scenario. Obviously, these differences depend on the mag- nitude of the seasonal variation. As canopy gas exchange rates are highest in summer, omitting seasonality could result in significant overestimations only when needle photosyn- thetic capacity is considerably lower in spring and autumn than in summer. Because this was not really the case at our temperate study site, it is only logical that differences were not significant in the present study. To the best of the au- thors’ knowledge, the literature does not report other studies which calibrated a process-based model with direct leaf-level photosynthetic capacity measurements to quantify the effect of seasonal photosynthetic capacity variation on simulated coniferous canopy gas exchange. Yet, Santaren et al. (2007) indirectly showed the importance of including seasonal pho- tosynthetic parameter variation in a study in which a process- based model was optimized to eddy covariance flux data for the abovementioned P. pinaster stand in France. The impor- tance of including seasonal variation has also been shown for a mixed deciduous forest (Wilson et al., 2001).
Mostrar mais

17 Ler mais

Operating characteristics of turbine mixers based on the analysis of power demand of the mixer’s drive

Operating characteristics of turbine mixers based on the analysis of power demand of the mixer’s drive

synthetic system sand with bentonite. This is so when the sand mix is made from fresh components. In roller mixers the rebonding agent is distributed during the repeated cycles of compaction and loosening, while the acting forces must be greater than cohesion. For that reason kneading and spreading operations are performed by the roller systems, involving rolling and slipping .

4 Ler mais

Modelling annual individual-tree growth and mortality of Scots pine with data obtained at irregular measurement intervals and containing missing observations

Modelling annual individual-tree growth and mortality of Scots pine with data obtained at irregular measurement intervals and containing missing observations

Site index was a non-significant effect in the growth models in the present study, which was unexpected, at least for the height increment model. This appears to indicate that the key factor driv- ing diameter and height growth for Scots pine in the study area is competition rather than site. Nevertheless, the inclusion of tree size and age, which are indicators of past growth, in the model, covers site effects and other site variables may therefore not be necessary. If both diameter and age are used together in growth modelling, the cumulative effect of past management may be sufficiently assessed (e.g., Harrison et al., 1986; Quicke et al., 1994; Schröder et al., 2002). A study on individual tree growth after thinning on Scots pine in Galicia (Crecente-Campo et al., 2009b) found that the G Lmod index and other indices based on G L were correlated with
Mostrar mais

10 Ler mais

Water balance in pediatric nephrology: construction of a Standard Operating Procedure

Water balance in pediatric nephrology: construction of a Standard Operating Procedure

Objective: To construct a Standard Operating Procedure (SOP) about the water balance, to be used by the health team in the care of children hospitalized in a pediatric nephrology unit. Method: The study was carried out in two stages: integrative review of the literature for the development of SOP and validation by specialists. The search for literature occurred in the electronic databases PUBMED, SCOPUS, LILACS, BDENF. After the bibliographic survey the construction of the SOP was performed, which was evaluated by specialists. The analysis was performed by calculating the Content Validity Index (CVI). Results: nine studies were selected as results of the integrative review. The sample of specialists was composed of nine professionals. The study was evaluated in six items, fi ve of which presented CVI = 1 and one obtained CVI = 0.77. Conclusion: the evaluation of specialists culminated in the validation of SOP, suggesting changes that were accepted and discussed with the literature. Descriptors: Water Balance; Hydro Electrolytic Balance; Nursing; Protocols; Pediatrics.
Mostrar mais

8 Ler mais

Diurnal pattern of the drying front in desert and its application for determining the effective infiltration

Diurnal pattern of the drying front in desert and its application for determining the effective infiltration

2001). The desert landscape primarily consists of unvege- tated or sparsely vegetated aeolian sand dune fields as a core, surrounded by desert plains, with pediments on the margin (Yang et al., 2003a). The elevation ranges from 1500 m in the southeast to 900 m above sea level in the northwest, with the mega dunes up to 400 m high in the southeast aligned in a SW-NE pattern (Dong et al., 2004). The mean grain size of the dune sand in this desert is between 0.21 mm and 0.22 mm (Jakel, 1996; Yang and Williams, 2003b). There are over 70 lakes in the interdune areas, of which the sur- face area vary from 0.2 km 2 on the southeastern edge of the desert to 1.6 km 2 slightly northwards, and the water depth from 2 m to 16 m (Yang and Williams, 2003b). On the sur- face, there is neither recharging into these lakes nor dis- charging from them, and there is no river in the entire desert (Yang, 2001; Wang and Cheng, 1999). With such hydrolog- ical conditions, vegetation in the study area is sparse. The plant or shrub communities depend mainly on the geomor- phology and on edaphic conditions. The dominant plant species are Haloxylon ammodendron, Psammochoa villosa, Phragmites communis, Artemisia ordosica, while in the area around lakes and springs the denser groundcover observable could be found (Polypogon monspeliensis, Triglochin mar- itima, Achnatherum splendens, Carex sp., Glaux maritima) (Gates et al., 2008a).
Mostrar mais

12 Ler mais

Is snow sublimation important in the alpine water balance?

Is snow sublimation important in the alpine water balance?

sphere which is visible at each location), hourly meteorological forcings of precipitation, global radiation, temperature, humidity, and wind speed, as well as the data character- izing the forest canopies in the area – the latter two data sources are described in the following sections. Fields of simulated wind directions are derived using the Penn State University – National Center for Atmospheric Research MM5 model and downscaled

48 Ler mais

Effect Of Shape And Plan Configuration On Seismic Response Of Structure

Effect Of Shape And Plan Configuration On Seismic Response Of Structure

These 9 models are shaped by considering Plan irregularities i.e. the plan area for each structure is same only there is difference of geometry. For all types of structure total numbers of storeys are 12.The elevation is same for all the 9 models. Distribution of each storey height is shown below,

5 Ler mais

Data-based modelling and environmental sensitivity of vegetation in China

Data-based modelling and environmental sensitivity of vegetation in China

and dry shrubland. The empirical model makes no prediction because the climate un- der this scenario is outside the range that the empirical models could predict based on current observations. The actual vegetation is temperate croplands, which are adapted to the climate with the help of irrigation. However, the North China Plain is one of the most water-scarce region in the world (having less than half the water availability per

33 Ler mais

Filtration of aluminum alloys and its influence on mechanical properties and shape of eutectical silicium

Filtration of aluminum alloys and its influence on mechanical properties and shape of eutectical silicium

Progressive materials with high-speed development in wide range of commercial applications are aluminum alloys Al – Si. Future of their further use is connected with their unique characteristic, resp. advantageous relation between mechanical properties and density. Largest use of these alloys is in the transport industry – automobile and aerial industry. Also often used in engineering industry and special role in army industry. Desirable mechanical properties may be considered one of the main reason for wide spectrum efficiency of aluminum alloys, therefore is very important to understand the factors, which have major impact on this properties. Main goal of this work was to execute group of experiments, to prove impact of filtration elements on morphology of eutectical silicon. Shape, deployment and scale of eutectical silicon are one of the factors, that have
Mostrar mais

4 Ler mais

Impact of Forest Harvesting and Forest Regeneration on Runoff Dynamics at Watersheds of Central Siberia

Impact of Forest Harvesting and Forest Regeneration on Runoff Dynamics at Watersheds of Central Siberia

In the paper disturbance of Angara river region forests were estimated and peculiarities of forest regeneration after logging and wild fires were analyzed. According to the landscape classification of the regional study, three groups of landscapes differencing on types of forest successions were developed. It was shown that water protective and water regulate functions of the Angara river re- gion forests change under commercial forest harvesting. Comparisons of the inventory and hydro- logical data detected that hydrological consequences of commercial forest harvesting are dependent on climatic parameters and forest regeneration peculiarities. In the continental climate conditions, when forest regeneration is delayed, snow storms are more active, snow evaporation increases and runoff reduces. In the process of logging sites overgrown with secondary small-leaved forest, snow accumulation increases and runoff increases, exceeding the value of annual runoff at undisturbed watersheds.
Mostrar mais

9 Ler mais

The Impact of E-Commerce Securi ty, and National Environment  on Consumer adoption of Intern et Banking in Malaysia and  Singapore

The Impact of E-Commerce Securi ty, and National Environment on Consumer adoption of Intern et Banking in Malaysia and Singapore

Relative advantage is defined as the extent to which a person views an innovation as offering an advantage over previous ways of performing the same task (Roger, 1983; Agarwal & Prasad, 1997). Because Internet banking services allow customers to access their banking account from any location 24 hours a day and 7 days a week, it provides an enormous advantage and convenience to users (Tan & Teo, 2000). It also gives customers greater control over managing their finances, as they are able to check their accounts easily. Besides, a customer’s Internet experience, his or her banking needs can affect his adoption. As there are more financial products and services, it is expected that individuals with many financial accounts and who subscribe to many banking services will be more inclined to adopt Internet banking. Tan and Teo (2000) has reported that potential adopters of Internet banking services are likely to own multiple banking accounts and subscribe to various banking services. Rogers argues that potential adapters, who are allowed to experiment with an innovation will feel more comfortable with the innovation and are more likely to adopt it. Thus, if customers have the opportunity to try the innovation, certain fears of the unknown may be minimized. Government policy could also aid or hinder Internet diffusion (Mbarika, 2002). This is consistent with the national systems of innovation theory that posits that government policies may encourage or mandate technology development and adoption (King et. al., 1994; Wolcott et. al., 2001). Tan and Teo (2000) suggest that the greater the extent of government support for Internet commerce, the more likely Internet banking will be adopted, thus, confirming Goh’s (1995) suggestion that governments can play an interventionist and leading role in the diffusion of innovation. Potential users in turn would view new applications such as Internet banking services more favorably and hence be more like to use them. Thus, the second alternative hypothesis is:
Mostrar mais

20 Ler mais

The research on effectiveness of conservation  of archaeological pine wood with low transverse (shrinkage) and high longitudinal shrinkage

The research on effectiveness of conservation of archaeological pine wood with low transverse (shrinkage) and high longitudinal shrinkage

Key words: archaeological wood, Scots pine ( Pinus sylvestris L.), conservation, shrinkage, hy- groscopicity. Adres do korespondencji – Corresponding address:[r]

9 Ler mais

Influence of tungsten and titanium on the structure of chromium cast iron

Influence of tungsten and titanium on the structure of chromium cast iron

Studies have proved that structure of the chromium cast iron greatly depends on the additionally introduced elements such as titanium and tungsten. Titanium is a carbide-forming element, but in contrast to other elements of this type it does not form complex carbides in the chromium cast iron, but only a TiC carbide, which is formed at high temperature in the liquid metal. Tungsten is also a carbide-forming (and pearlite-forming) element but, like titanium, is rarely used in the manufacture of chromium cast iron. High melting points of tungsten and titanium may cause difficulties in the metallurgical process of chromium cast iron manufacture. Tungsten effect on the mechanical properties is similar to that of molybdenum, although it is weaker. Tungsten increases the hardenability of cast iron. Currently, the use of tungsten can be justified because of its price slightly lower than that of molybdenum.
Mostrar mais

4 Ler mais

EstimatE of GroundwatEr rEcharGE BasEd on watEr BalancE in thE unsaturatEd soil ZonE

EstimatE of GroundwatEr rEcharGE BasEd on watEr BalancE in thE unsaturatEd soil ZonE

Unsaturated zone’s storage variation was calculated as being a difference between the water content in the soil regarding the month in question and the previous one. A model for the balance was implemented by Melo (2013), considering that each area with a different soil use has a maximum water retention capacity, depending on the root-zone extension within the unsaturated zone (Smax). The idea underlying this approach is to represent water storage and flows by means of linear reservoirs, similar to the ones applied by Raneesh and Thampi (2013) and Kwon et al. (2012).
Mostrar mais

9 Ler mais

Principles of fish welfare assessment in farm rearing conditions

Principles of fish welfare assessment in farm rearing conditions

Considering that mechanism of stress reaction and its effects on fish body are similar for fish and terrestrial mammals, assessment of welfare is conveyed in a similar way and is based on determining the degree of fulfilment of basic needs of the organism (Lembo and Zupa, 2010). The concept of animal welfare is based on respecting the ‘five freedoms’ (Poli, 2009): freedom from hunger and thirst, freedom from discomfort, freedom from pain, injury or disease, freedom to express normal behaviour, freedom from fear and distress. To achieve these freedoms environment plays a great role. According to Broom (1986) welfare of animal can be defined as the level of adaptability to the environment. The level of welfare is assessed based upon measurable indicators. During welfare assessment, measured values are compared to the ones which are considered as optimal for specific species and category of animals in certain breeding conditions. For Atlantic salmon specific standards for farm rearing exist (RSPCA, 2007). Considering other commercial species more data about fish reacting on different stimulus and in different environmental conditions are needed.
Mostrar mais

10 Ler mais

Separating the effects of changes in land cover and climate: a hydro-meteorological analysis of the past 60 yr in Saxony, Germany

Separating the effects of changes in land cover and climate: a hydro-meteorological analysis of the past 60 yr in Saxony, Germany

The method can be used to identify non-stationary changes in the average water–energy partitioning and to quantify the contributions of the most general impacts (Renner and Bernhofer, 2012). It is, however, important to note that due to the strict definition of climatic change impacts, and the more open definition of land-surface change impacts it is not possible to directly trace the respective process causing the observed change. To identify the role of sub-scale processes, process-based models are required. As these models gener- ally require more input data, they additionally suffer from model parameter and model structure uncertainties (Seibert and McDonnell, 2010). Hence, these more detailed analyses should be approached in a top-down manner (Klemeš, 1983), starting with a simple first order approach as illustrated here. The proposed method is prone to input data uncertain- ties, especially precipitation, potential evapotranspiration and runoff data. However, if we assume that random errors average out over longer periods as used here, these uncertain- ties may diminish. We also tested the influence of systematic uncertainties, such as precipitation bias correction, station network changes, the estimation of potential evapotranspi- ration, or the uncertainty of deriving spatial basin scale me- teorological input data. All of these play a role but resulted in shifting the whole data set rather than changing its shape within the water–energy partitioning plots.
Mostrar mais

17 Ler mais

Separating the effects of changes in land cover and climate: a hydro-meteorological analysis of the past 60 yr in Saxony, Germany

Separating the effects of changes in land cover and climate: a hydro-meteorological analysis of the past 60 yr in Saxony, Germany

To account for this effect, we performed a precipitation correction of the annual pre- cipitation sums using the Richter (1995) scheme which is largely based on rain gauge sheltering factors and altitude. The bias correction only led to a shift in precipitation related data, but did not change the overall features. For further analysis, we used the uncorrected values. A second uncertainty is the varying number of available stations in

44 Ler mais

Influence of vibrations during crystallization on mechanical properties and porosity of AlSi13Cu2 alloy

Influence of vibrations during crystallization on mechanical properties and porosity of AlSi13Cu2 alloy

Today’s industry aims at such situation, where number of defective products, so called defects shall approach to zero. Therefore, one introduces a various changes in technology of production, introduces improvements which would help in accomplishment of this objective. Another important factor is introduction of different type of testing, which shall help in assessment which factor has significant effect on quantity of rejects, and which one could be neglected. Existence of casting rejects is unavoidable; therefore a new ideas, technologies and innovations are necessary in the entire widely understood foundry branch, in order to minimize such adverse effect. Performance of tests aimed at unequivocal determination of an effect of vibrations during crystallization on mechanical properties and porosity of the AlSi13Cu2 alloy was the objective of the present work. To do this, there were produced 36 castings from AlSi13Cu2 alloy. All the castings underwent machining operations. Half of the casting was destined to strength tests, the other half served to determination of an effect of vibrations on porosity of the alloy. The specimens were divided into 12 groups, depending on amplitude of vibrations and tilt angle of metal mould during pouring operation.
Mostrar mais

4 Ler mais

Show all 10000 documents...