δ15n and δ18o values of nitrous oxide

... determination of only the desorption (main drainage) curve and the imbibition (main wetting) curve 69.4.1 APPLICATION OF DESORPTION AND IMBIBITION CURVES The shape and magnitude of desorption and imbibition ... presence of structure changes only the shape of the curve and not the value of us ß 2006 by Taylor & Francis Group, LLC storage of fluids (liquids, gases) in the soil profile The sizes of soil ... (Romano and Santini 2002) Plant growth and performance is critically dependent on adequate supplies of air and water in the root zone Convenient and popular measures of the soil’s ability to store and...

Ngày tải lên: 12/08/2014, 02:23

... layer of subsoil composed of gravel and sand sediments of quaternary origin laying above impermeable clay sediments of tertiary origin The forest stand was composed of oak (Quercus robur L., 78% of ... the model tree (V T.tree) and of the stand (VT.stand) at the area of Astand Atree = Astand (VT.tree / VT.stand) crown ground plan, Actmax or similarly by the ground plan of root systems, Artmax, ... analyzed shrub and herbaceous layer Standard errors of the appropriate regressions were about 8% for aboveground parts of trees and and 19% for the depth and ground plan area of root systems...

Ngày tải lên: 08/08/2014, 14:21

... been often reported, among conifer species (e.g in Sandford and Jarvis [42]) Our observation probably results from the averaged response of a whole canopy, resulting from the mixing of leaves of ... Evaporation and canopy characteristics of coniferous forests and grasslands - Review, Oecologia 95 (1993) 153–163 [27] Köstner B., Biron P., Siegwolf R., Granier A Estimates of water vapor flux and canopy ... Gries W., Kucera J., Canopy transpiration and water fluxes in the xylem of the trunk of Larix and Picea trees: a comparison of xylem flow, porometer and cuvette measurements, Oecologia 66 (1985)...

Ngày tải lên: 08/08/2014, 14:22

... possibly the result of the acidification of the apoplast leading to cell wall loosening (Davies, proton-induced 1973) References Effects of Atmospheric Pollutants on Forests, VVetlands and Ac Ecosystems, ... significant water stress Water stress occurs when the rate of water loss exceeds the rate of uptake It was clear that the rates of day and night transpiration did not differ between treatments ... result is in contradiction to those of several investigators who noted a significant effect of acid rain/mist upon cuticle structure and/ or resistance The lack of apparent effect in the present...

Ngày tải lên: 09/08/2014, 04:20

... the EPA Office of Water/Office of Science and Technology/Standards and Applied Science Division To conduct the assessment required estimates of several factors The factors and the sources of the ... Humans, Terrestrial and Avian Wildlife, and Aquatic Life to Dioxins and Furans from Disposal and Use of Sludge from Bleached Kraft and Sulfite Pulp and Paper Mills Office of Pesticides and Toxic Substances, ... lakes), and two dilution models Dilution factors provided by Office of Water publication and Regional EPA personnel One of the dilution models was developed by EPA/Office of Research and Development/Exposure...

Ngày tải lên: 24/03/2014, 05:20

... our understanding of the effects of forests and watershed characteristics on soil water retention and flow regimes, respectively It will help us better understand the consequences of deforestation ... influences of watershed characteristics, forest cover, and forest distribution on storm runoff responses of 15 representative watersheds in Vietnam; and to determine peak discharge of these watersheds ... predictors of initial flow, rainfall, and rain intensity c) to identify the roles of forest cover on soil erosion prevention; and to produce a map of required forest areas for protection of soil...

Ngày tải lên: 03/04/2014, 12:22

... are in the earth and/ or stone work The quantity of digging of drains, collection and transport of stones, maintenance of the structures, etc will provide an indication of the cost of the scheme ... and chapters and give examples of small-scale systems Part II covers the subject of soil moisture retention (conservation) Chapter and describe a number of measures to increase infiltration of ... Infiltration and runoff Rainfall and runoff Crop water requirements Calculation of C:CA ratio 13 13 14 14 17 19 22 4.1 4.2 Selecting a water harvesting technique An overview of the systems and their...

Ngày tải lên: 04/07/2014, 02:20

... types of mineral particles: sand, silt and clay A soil which consists of mainly large sand particles (a coarse textured soil) is called a sand type of soil or sandy soil; a soil which consists of ... often find that soils are composed of a mixture of mineral particles of different sizes For example the sandy loam soil of Table consists of an equal mixture of sand and silt particles Table 1: Typical ... the soil surface as runoff The amount of runoff depends on the absorbtion capacity of the soil and the amount of rain The amount of rain which falls in a certain period of time on the soil is...

Ngày tải lên: 04/07/2014, 02:20

... example of Figure 12) and at right angles to the ridges, to prevent flow of runoff water through the furrows (erosion) and to ensure evenly spread storage of runoff 38 Water harvesting and soil ... runoff (and tillage) from the lower side of the upper line (Figure 10 (b)) and deposited at the higher side of the next line lower In that way gradually a horizontal terrace is built up and runoff ... bunds, constructed of earth and covered with a layer of stones Figure 17: Cross section of an earth bund The spillway is made of stones, and is usually 80 cm wide at the base and 10-15 cm high (see...

Ngày tải lên: 04/07/2014, 02:20

... at different times Combinations of grasses and legumes are common, as well as of cereals and creeping legumes, e.g millet and groundnuts (Figure 28) An advantage of many legumes is that they fix ... 30 shows a narrow bed and furrow and two variations of a broad-bed and furrow It is clear that the broad-bed and furrow system makes it possible to combine different crops and planting densities ... ridge and furrow system (planting distance 75 cm) Figure 30B gives an example of a broad-bed and furrow using the same crop and planting distance Figure 30C shows a combination of maize and pigeon...

Ngày tải lên: 04/07/2014, 02:20

... improve fallow land, alternated with periodic crops of millet, sorghum or pulses Constraints The risk of soil erosion is higher on land left fallow, especially on sloping land and where rainfall ... for a mid-season change of plan according to the amount of rain in the early part of the season ? A combination of legumes and cereals may increase the nitrogen status of the soil ? Plants with ... planting and harvesting ? Higher yields per unit area are obtained as a result of higher growth rates, fewer losses due to diseases, insects, and weeds, and more efficient use of water, light and...

Ngày tải lên: 04/07/2014, 02:20

... the same protocol of measurement regarding to distance, depth and period Comparison of mean values of θ were conducted by means of three-ways ANCOVAs, with distance, depth, and season as independent ... potential values obtained during the summer of 2002 (CL and ST sites) and 2003 (BA site) in isolated Quercus ilex trees, and monthly potential evapotranspiration values (PET) Predawn and midday ... weighted every 20 cm, and aliquots were taken for the determination of θ, in order to get the dry weight of soil A total of 1290 determinations were done Aliquots of three randomly selected trees...

Ngày tải lên: 07/08/2014, 16:21

... water reserve of day i (mm), Ri-1 is soil water reserve of day (i-1), Pi is day i rainfall (mm) and ETi is total stand evapotranspiration losses of day i (mm), i.e the sum of tree and understorey ... amount of rain, In% is also function of the evaporative demand (wind speed, radiation, vapour pressure deficit) and of the continuous or discontinuous pattern of the rain [2, 11, 35] 4.2 Over -and ... Evaporation and canopy characteristics of coniferous forests and grasslands, Oecologia 95 (1993) 153–163 [20] Ladekarl U.L., Estimation of the components of soil water balance in a Danish oak stand from...

Ngày tải lên: 08/08/2014, 00:22

... paired -values) : (a) Probe type and depth (0–20, 20–40, 40–60 and 60–80 cm); (b) Probe type and range of soil moisture (0.08– 0.14, 0.14–0.21, 0.21–0.28 and 0.28–0.35 cm3 cm–3); (c) Probe type and ... constant of water (Kw), which is temperature-dependent, ranges from 74 to 84 and is about 20fold higher than that of mineral solids (between and 5), and about 80-fold higher than that of air (1.0005 ... the end of the probe, or at the interface between regions of different permittivities, part of the signal is reflected back and the apparatus detects and processes this signal The speed of propagation...

Ngày tải lên: 08/08/2014, 01:21

... entire range of VPD and thus permits comparison of the data independently of specific VPD ranges On the basis of transpiration rates and water potential differences between the soil and leaves, ... Values of term f(VPD) in equation for different age classes of shade and sun foliage Figure Predicted versus observed values of leaf conductance (gL) in the current-year sun foliage in 2000 and ... the sensitivity of leaf conductance in foliage of different age and position to the atmospheric demand and liquid phase conductance, VPD and GT were changed by 10% from the average values in the...

Ngày tải lên: 08/08/2014, 01:21

... cavitation than those of F excelsior (figure 3A and D), the major differences occurring for low ψ values (ψcav at –1.0 and –1.5 MPa and ψ100 at –1.8 and –4.2 MPa for A pseudoplatanus and F excelsior ... values of the transpiration indicated in tables and figures were the maximum values (Emax) All of these measurements were made during the summers of 1999 and 2000, on two sunny days in each season ... ψ100 which indicated the water potential values that induced the start of the embolism, and 100% of the maximal hydraulic conductivity, respectively ψcav and ψ100 were measured graphically from...

Ngày tải lên: 08/08/2014, 14:21

... glass, several plastics and decorative papers Wood is often favored because of its aesthetic properties, particularly color A survey of wood-using professionals by Mazet and Janin (1990) showed ... HUNTERLAB simulating the CIE standard illuminant A (corresponding to incandescent light) and an observation angle of 10° The color is represented by the values L*; a*, b*, C* and h* (fig 2) Wood Extractions ... suggestion that the wood of sessile oak is slightly redder than that of pedunculate oak However, Scalbert et al (1986) found no differences in the quantity and quality of extractives of the species Rink...

Ngày tải lên: 08/08/2014, 19:21

... petroleum refining • The management and regulation of cyanide in water and soil can be very challenging because of the complexity of the chemistry and toxicology of cyanide and, accordingly, the risk ... fear of cyanide, regardless of its form and location • The focus on total cyanide content has made regulations of cyanide in water and soil confusing and inconsistent, and has led to management and ... is a professor in the Department of Civil and Environmental Engineering at Carnegie Mellon Dr Dzombak’s research and professional interests include aquatic chemistry; fate and transport of chemicals...

Ngày tải lên: 11/08/2014, 20:20

... Fe3[Fe(CN)6]2(s), … FIGURE 2.1 Forms and species of cyanide in water and soil and metal–cyanate complexes, and cyanogen halides Aqueous free cyanide is the sum of hydrogen cyanide, HCN, and its deprotonated ... are thousands of former manufactured gas plant (MGP) sites throughout the eastern and midwestern United States and © 2006 by Taylor & Francis Group, LLC Physical and Chemical Forms of Cyanide ... The aim of this chapter is to provide an overview of the common physical and chemical forms of cyanide that occur in water and soil systems In the following sections, the cyanide species of primary...

Ngày tải lên: 11/08/2014, 20:20

... atmosphere, and the presence of nitrogen and carbon The quantity of cyanide produced in the coking of coal has been reported to be about 1.5 to 2.0% of the nitrogen content of the coal [3] A portion of ... flow diagram of the Andrussow process This diagram shows the recovery/recycle of ammonia and waste heat-design features that improve the efficiency and economy of the process Details of the process ... Periodic blasts of air and supplemental fuel (oil) are fired into the reaction mixture [9] This environment of high temperature, available carbon as carbon monoxide and carbon dioxide, and nitrogen...

Ngày tải lên: 11/08/2014, 20:20