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1.
The individual-based combined forest model EFIMOD including the soil-sub model SOMM has been used for the simulation of Scots
pine stand growth and soil organic matter (SOM) accumulation on a humus-free bare mineral surface. The growth of Scots pine
plantation, with an initial density of 10 000 trees ha−1 and average tree biomass of 0.01 kg was simulated for 50 yr under Central European climatic conditions (i) with varying atmospheric
nitrogen inputs and (ii) different rates of initial application of raw undecomposed organic material or compost, on humus-free
parent material. The accumulation of typical raw humus was simulated in all cases. The accumulation was most intensive in
the simulation of high atmospheric nitrogen input. The humus pool in the mineral topsoil was small but achieved its maximum
value with compost application. SOM nitrogen accumulation was scant in all cases, except the compost applications with low
atmospheric nitrogen input. No statistically significant differences of SOM and stand parameters were found between variants
without organic matter and those with low input of organic manure. However, the maximum relative rate of SOM and nitrogen
accumulation was found in the scenario without organic manure, under slowly growing unstable Scots pine plantation.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
2.
Characterization of soil organic matter from a sandy soil in relation to management practice using FT-IR spectroscopy 总被引:1,自引:0,他引:1
Previous results from differently fertilized long-term field experiments on a sandy soil suggested that the chemical composition
of soil organic matter (SOM) is affected by fertilization. The objective of this paper is to confirm this finding for a site
with higher soil-clay contents. Four combinations of different fertilizer treatments at long-term field experiment located
at a sandy loam were selected: liquid manure (LM), liquid manure+N (LM+N), straw+N (S+N) and mineral nitrogen only (N). Soil
organic matter was extracted using sodium pyrophosphate solution at pH of 10 and hot water. The extracts were analyzed using
Fourier-Transform infrared spectroscopy. The results indicate that the composition of SOM from the hot water extracts did
not show significant differences while the sodium pyrophosphate extracted SOM is affected by the type of fertilization. Soil
samples fertilized with LM+N and S+N show the highest intensity of the carboxyl band. This can be explained by the fact that
the combination of S+N fertilization with green manure leads to an enrichment of carboxyl groups in SOM. Differences between
the band intensities of the treatments for the SOM samples are, however, not as distinct as for the sandy soil samples. This
is possibly a result of the higher clay content and lower age of the long-term experiment at the sandy loam site. The intensity
of the carboxyl band of the SOM is correlated with the cation exchange capacity of the soil samples. The composition of SOM
may, in addition to the SOM content, be used for studying quantitative effects of different management practices or even land
use changes on soil properties.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
3.
Soils disturbed by long-term opencast mining were treated with organic waste materials for reclamation. Humic substances were
extracted from waste and soil samples and analysed using pyrolysis-gas chromatography/mass spectrometry and electrofocusing.
Furthermore, analytical pyrolysis permits to study all starting materials in situ. According to structural similarities, the
statistical evaluation of the pyrolysis results clearly indicates three sample groups. The first group, called compost, implies
the waste materials compost and composted sewage sludge. Moreover, pyrolysis revealed that coal humic substances are predominant
in brown coal sludge, pure mine soils and mine soils treated with the different organic waste materials. They constitute the
second group. The sewage sludge contains a high nitrogen potential, as expected, and represents the third group. Finally,
pyrolysis generally showed the specific structural characteristics of humic and fulvic acids, respectively. Electrofocusing
yielded for all samples a signal pattern that is typical of humic substances. However, number and ratio of the signals differ
according to the special structural features of the samples.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
4.
Application of compost to agricultural soils may be beneficial for crop production by increasing soil fertility and supplying
plant nutrients, however, any raise of the soil organic matter content may increase the potential for unintended groundwater
contamination by nitrate leaching. In this paper, the effect of long-term compost applications on nitrate leaching, soil organic
matter content, and crop production is analyzed using results of simulation scenarios for agricultural sites with loamy and
sandy soils. Simulations were carried out using the Danish Nitrogen Simulation System (DAISY) which describes the nitrogen
balance in a one-dimensional soil-plant-atmosphere system and considers compost type and application rate as well as management
and cropping practice. Estimations of hydraulic and solute transport parameters are based on pedotransfer functions. Data
from a 4.5-year period of field experiments with compost applications in northern Germany as well as from laboratory experiments
with compost amended soil are used for model calibration. Simulation results suggest that: (i) with respect to nitrogen turnover
the differences between compost types (i.e., non-matured and matured) are small compared to site-specific properties (i.e.,
soil temperature and water balance) and management practices (i.e., crop rotation) when considering a compost application
period of 50 years; (ii) with respect to nitrate leaching the effect of different compost application scenarios is highly
sensitive at the sand and relatively small at the loam site; and (iii) relatively high crop yields and acceptably low nitrate
concentrations in the drainage water are obtained at the sand site when applying a combination of 10 t compost/ha/yr and soil-
Nmin adjusted mineral nitrogen additions of about 20 kg/ha/yr to a winter-grain dominated crop rotation. Further optimization
may be possible by applying reduced rates of the (economically interesting) non-matured compost.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
5.
Organic matter composition and degree of humification in lignite-rich mine soils under a chronosequence of pine 总被引:1,自引:0,他引:1
In the Lusatian mining district, in the eastern part of the Federal Republic of Germany, organic matter of reclaimed mine
soils consists of a mixture of lignite and recently formed soil organic matter (recent carbon). The aim of the study was to
investigate the recent carbon accumulation and the degree of humification of a chronosequence of young mine soils under forest.
The lignite content of the forest floor, Ai (0–5 cm) and Cv horizons (1 m depth) was determined by 14CU activity measurements and the structural composition of the organic matter was characterised by 13C CPMAS NMR spectroscopy. To obtain a characterisation of the degree of humification, the soil samples were analysed for the
content of polysaccharides, proteins, lignin and lipids by wet chemical methods. 14C activity measurements indicate that at the oldest site, comparable amounts of carbon accumulated in the first few centimetres
of the soil profile than in natural forest soils. 13C CPMAS NMR spectra of the organic matter in the Ai horizons of the three soil profiles were dominated by aromatic and alkyl
carbon species characteristic for lignite, but indicated as well an increasing contribution of carbon species from decomposing
plant litter with soil age. When the results from wet chemical analyses were normalised to the total carbon content no changes
with age could be noticed. After normalisation of the amount of litter compounds to the recent carbon content, the carbon
identified by plant litter compound analysis decreased with increasing depth and increasing age of the soils. After 32 years
the values are comparable to those of natural forest soils. These observations were confirmed by increasing degree of lignin
alteration with stand age and soil depth. The data of wet chemical analyses complement data obtained by 14C activity measurements and 13C CPMAS NMR spectroscopy and lead to the conclusion that 32 years after reforestation the degree of humification of the soil
organic matter is in the same range as those of natural sites.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
6.
It is a necessity to have a successful method to separate, quantify and define the active and passive soil organic matter
pools for appropriate verification of models. In this study, the organic carbon content of long-term bare fallow soils was
used as an indicator of the size of the stable soil organic matter pool. Although soil texture and soil structure are widely
accepted as having an influence on the stable pool, most soil organic models neglect the relationship between soil structure
and carbon stabilization. Therefore, the aim of this presentation is to estimate the size of the stable carbon pool and to
relate it to soil texture and structure properties. It was calculated that over 50 yr, under bare fallow conditions, the relative
decrease in the amount of carbon (C) for the most stable pools ranged between 2 and 12%. In comparison, for the less stabilized
pools the relative decrease was calculated from 50 to 100%. This indicates that the organic carbon content of long-term bare
fallow soils should be very similar to the size of the most stable C pool. We also observed that the amounts of carbon associated
with primary particles <20 μm for numerous soils with contrasting carbon content, soil texture, and management practices showed
a lower and an upper limit. Both these limits and the carbon content of long-term bare fallow soils (which were assumed to
be similar to the size of the stable pool) were related to the content of primary particles <20 μm in the soil. To calculate
these relationships, an equation was used including one term to describe the influence of soil texture and another to describe
that of soil structure. The calculated regression for the bare fallow soils corresponded very well to the lower limit of carbon
content associated with primary particles <20 μm. The upper limit was estimated only by increasing the regression parameter
which is related to the amount of C per unit primary particles <20 μm. Considering the many published results of the influence
of soil texture and structure on carbon stabilization processes in soil, the stable pool may be defined as the capacity of
soils to sorb C. The upper limit of carbon content associated with primary particles <20 μm may be interpreted as the capacity
of soil to protect C.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
7.
Impact of some ecological factors on the occurrence of poultry soil-inhabiting keratinophiles 总被引:1,自引:1,他引:0
Investigations were conducted to assess the ecological factors governing distribution and survival of keratinophilic fungi
in poultry farm soils. All the poultry farm soils were rich in humus and the keratinophilic fungi were generally found to
be proportional to the soil organic matter. These soils were nearly neutral to weakly alkaline and organically rich with a
high content of organic carbon, nitrogen, phosphorus, potassium, magnesium, calcium and iron.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
8.
On a study site in the Lusatian lignite mining region (Germany), sandy mine spoil was ameliorated with either sewage sludge,
compost or mineral fertilizer. Plots were sown with the grass Secale multicaule and planted with pine seedlings except for
a control that was not meliorated and not revegetated. Pitfall catches of ground beetles in 1996/97 yielded high numbers of
species and individuals directly after revegetation. The dominant beetles were xerophilic species, known to prefer open sandy
sites. Catches in different plots were positively correlated with the amount of vegetation cover and declined as follows:
amelioration with sewage sludge > compost > mineral fertilizer > untreated control. Even beetles characteristic of open sandy
sites showed a distinct preference for plots with high vegetation cover treated with organic waste. For the dominant species,
an attraction to shelter and a more balanced, humid microclimate is assumed. A year-to-year comparison showed an increase
in beetles typical of dry grasslands and ruderal sites in the second year, while characteristic species of open sandy sites
decreased. Application of organic waste combined with revegetation led to an immediate increase in beetle numbers. In the
long term, revegetation would be expected to reduce suitable habitats for endangered ground beetles which prefer open sites
with poor sandy soils.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
9.
Experiments in a rewetted fen show large differences in root decomposition rates among Phragmites australis, Carex paniculata,
and Carex riparia. With equal water table fluctuations no differences in decomposition were observed in the two rewetting
variants, with temporary standing and constantly flowing water. The marked differences among species are therefore attributed
to differences in plant material quality, though C/N ratio is shown not to be of main influence. Based on low decomposition
rates, Phragmites australis proved the species most suitable for (renewed) peat accumulation under sufficient wet conditions.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
10.
The lignite and pyrite containing spoil substrates of the Lusatian mining district are marked by very high acidity and salt
concentrations due to pyrite oxidation and by a very low content of pedogenic organic matter and nutrients. The effects of
fly ash application to neutralize the produced acid and of organic waste material application to improve the ecological soil
functions were studied considering the carbon and nitrogen cycling. Nineteen, 38 and 57 t ha−1 sewage sludge and 22, 44 and 66 t ha−1 compost were applied to ameliorated lignite and pyrite containing substrate. An automated soil microcosm system was used
to analyse the solid, gaseous and liquid phases. Almost 9% of total N applied with sewage sludge (620, 1240 and 1860 t N ha−1 applied) were lost over a period of 150 days mainly as NO3-N. The total N losses from compost treatments were three times lower (2.8–3.1% of applied Nt) and occurred in similar quantities
as NH4-N and NO3-N. Only sewage sludge treatments showed slightly increased N2O emissions at the beginning of the experiment. CO2 emissions determined the carbon losses of all treatments. The C losses amounted to 3.2–4.7% and 1.5–2.7% of Ct applied with sewage sludge and with compost, respectively.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
11.
Many mine spoils present at the surface of reclamation sites in the Lower Lusatian mining district are carboniferous substrates,
i.e. contain geogenic organic matter. Depending on its susceptibility to microbial degradation, geogenic organic matter might
influence the establishment of a carbon requiring microflora in mine spoils. As geogenic organic matter contains substantial
amounts of organic nitrogen it is also a potential source for plant available N. The objective of the present study was to
quantify C and N mineralisation and microbial biomass in geogenic organic matter present at reclamation sites in Lower Lusatia.
We also studied, whether these properties can be influenced by raising the originally low pH to near neutral conditions. In
laboratory incubation studies, the rates of CO2 evolution and net N mineralisation were determined in geogenic organic matter and carboniferous mine spoil with and without
addition of lime. At the same time, microbial biomass carbon was estimated. As a reference, soil organic matter originating
from the humus layer of a 60-year-old Pinus sylvestris stand was used. As indicated by the initial rates of C mineralisation,
geogenic carbon was microbially available but to a lower extent than soil organic carbon. During incubation, C mineralisation
remained constant or tended to increase with time, depending on the origin of the sample, while it decreased in soil organic
matter. Unlike in soil organic matter, in geogenic organic matter and carboniferous mine spoil, C mineralisation was not consistently
promoted by lime addition. Prior to incubation, microbial biomass in geogenic organic matter and carboniferous mine spoil
was about 10-fold lower than in soil organic matter and tended to increase with incubation time while it decreased in soil
organic matter. Similar to C mineralisation, microbial biomass in geogenic organic matter increased after liming, while it
declined in carboniferous mine spoil immediately after lime addition. Rates of net N mineralisation were very low in geogenic
organic matter and carboniferous mine spoil regardless of the length of incubation and could not be enhanced by raising the
pH. It was concluded, that in mine spoils where accumulation of soil organic matter has not yet occurred, geogenic organic
matter can be favourable for the establishment of a heterotrophic microflora. However, in the short term, geogenic matter
is no source for plant available N in mine spoils.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
12.
Greenhouse experiments were conducted in order to determine for carboniferous and non-carboniferous mine spoil substrates
from the Lusatian lignite mining area (i) the suitable extraction method for plant available P, (ii) the soil capacity for
immobilisation of P and (iii) the impact of sewage sludge and compost on P availability. Ca-lactate extraction (DL) and NH4F-extraction (Bray) were both suited equally well for the determination of plant available P as they extracted similar amounts
of P on both spoils, they showed a close correlation with each other (R=0.97 2) and they showed a close relation with plant P uptake (R2=0.63 and R2=0.66, respectively). Phosphorus recovery from limed carboniferous mine spoil five days after mineral fertiliser application
was only 50%, and decreased to 30% after 54 days. As pH was increased from 3.0 to 5.0 the amount of P immobilised decreased
only by about 5%. Several pH dependent processes of P immobilisation and release could occur concurrently counteracting each
other. One process could be P sorption to newly formed hydroxy-Al-surfaces but P desorption could also take place as pH increases
by decreasing surface positive charge. Finally, due to high Ca concentrations in spoil solution formation of Ca-phosphates,
even at lower pH values, cannot be excluded as a possible mechanism of P immobilisation. As part of the P is bound in organic
matter, application of P with organic matter resulted in a lower P recovery compared to mineral P-fertiliser. However, the
amount of P recovered did not differ between carboniferous and non-carboniferous mine spoil, if P was applied in the form
of organic matter, indicating that the application of P with organic matter might be a measure to overcome P immobilisation
in carboniferous mine spoils.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
13.
The impact of organic waste material and fly ash on microbial and chemical pyrite oxidation was investigated in a field experiment,
as well as in column tests under laboratory conditions. For the field experiment, pyritic mine spoil was ameliorated with
fly ash and treated either with mineral fertiliser, with sewage sludge or with compost. Independent of treatment, during the
18 months following application, the pyrite-S contents decreased steadily in the top spoil (0–30 cm depth). However, high
variations of the pyrite-S content were observed. Compared to other pyrite oxidation studies, the pyrite content of the mine
spoil at the experimental site was low. Therefore, a model spoil with a higher pyrite content, derived from Tertiary strata
of the overburden sequence in the same open-cast mine, was used for the column experiments. For the first column experiment,
the model spoil was mixed with fly ash and mineral fertiliser, reflecting the common reclamation practice in the Lusatian
open-cast lignite mining district. Columns with this spoil were either inoculated with different cell numbers of autochthonous
acidophilic bacteria, isolated from the model spoil, or with a commercial strain of Thiobacillus ferrooxidans. The ratio of
sulphate-S to total S was used as a measure for the degree of pyrite oxidation. The ratio of sulphate-S to total S increased
within 28 days of incubation. The increase was related to the inoculated cell numbers of bacteria, but independent of the
origin of the bacteria. It can be stated, that autochthonous bacteria from the model spoil oxidised pyrite at a similar rate
as did the commercial T. ferrooxidans strain. For the second column test, mineral fertiliser, sewage sludge or compost were
applied to the model spoil. The columns were inoculated with autochthonous bacteria, isolated from the model spoil. Application
of sewage sludge and compost seemed to promote the weathering of pyrite, as the ratio of sulphate-S to total S increased more
rapidly in these treatments compared to control or mineral fertiliser application. Both experiments showed an increase of
cell numbers of inoculated bacteria, independent of the ratio of sulphate-S to total S.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
14.
A disposable and inexpensive corer is described that offers a versatile method for sampling soft soils with a large organic
content. The cans are suitable for the immediate collection of soil and for field incubations. Fine roots are sliced easily
during insertion of corers by the sharp bottom edge, and the thin walls and the high thermal conductivity of steel aid transfer
of heat energy between the bulk soil and the sample. If desired the cylinders may be perforated, have the upper cap removed
and also can be used as an indicator of anaerobic soil conditions.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
15.
To fulfill the purpose as a sink for trace elements, soils must not be overloaded with As and Cd. Therefore, it is necessary
to get knowledge of the sorption capacities of soils on a regional scale. The determination of these sorption capacities for
large areas is, however, impeded by the great expenditure of laboratory work involved. With data presented here retention
capacities for cadmium and arsenic from routinely determined soil parameters are estimated. In batch experiments the sorption
behaviour of 40 soils from the area of Freiberg/Saxony in Germany was examined. The obtained sorption isotherms from the laboratory
were fitted to the Freundlich equation (S = k*Cm). The two constants (k, m) of this equation were used for multiple linear regression to correlate the sorption capacity and
the soil parameters, namely clay content, pH value, total organic carbon, and dithionite extractable Fe contents. Due to long
lasting ore mining of Freiberg there exist high background levels in that area for the two surveyed elements As and Cd. Therefore,
this study offers two different mathematical procedures to take these contaminations into account. Thus the experimental data
were corrected before they were fitted to Freundlich and pedotransfer equations were determined. Using the transfer equation,
parameter k and m for cadmium sorption could be estimated with statistical certainties of 91% and 61% (adjusted R2), respectively, whereas the predictability for the arsenic sorption is not practicable because achieved R2 values are very low (17% and 7%).
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
16.
Immobilization in polyvinyl foam resulted in an increased carbon fixation and release of fixed carbon in Anabaena variabilis
while in A. azollae both processes decreased.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
17.
The effects of a slow-release N-enriched rock powder on soil chemistry, on the development of the soil vegetation (field layer
vegetation), on the nutritional status of pine seedlings (Pinus sylvestris L.), and on decomposition rates of cellulose in
lignite-poor mine spoils were studied. In the initial phase after afforestation fertilization caused a significant increase
in NO3
−-N concentrations in the soil solution of the top-soil (0–60 cm). Subsequently, NO3
−-N concentrations of all N fertilized treatments decreased with the exception of the highest N application area (500 kg N
ha−1). This decrease of NO3
−-N concentrations was related to the establishment of a field layer vegetation, which developed according to the amount of
N applied. In the above-ground phytomass of the field layer vegetation a maximum N accumulation amount of 22 kg ha−1 was measured. Cellulose decomposition increased with higher N application rates. In the second year after N-fertilization,
the pine needles indicated insufficient supply for almost all nutrients except for N. The deficiency symptoms were most pronounced
at the plots that had received the highest amounts of nitrogen. This phenomenon appears to be related to the competition by
the field layer vegetation.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
18.
Impact of application of organic waste materials on microbial and enzyme activities of mine soils in the Lusatian coal mining region 总被引:2,自引:0,他引:2
C. Emmerling C. Liebner M. Haubold-Rosar J. Katzur D. Schr?der 《Plant and Soil》2000,220(1-2):129-138
The objective of the present work was to study the short-term stimulation of microbial and enzyme activity in mine soils by
application of organic waste materials in lysimeter and mesocosm studies. The mine soils derived from tertiary and quaternary
deposits were ameliorated with brown coal filter ash (tertiary deposits) and lime (quaternary deposits). At the beginning
of recultivation the soils were treated with varying amounts of sewage sludge, coal sludge, composted sewage sludge and compost
to a depth of 30 cm. In the first 2 years after application of organic waste materials we found a very low level of microbial
properties especially in the sandy materials from quaternary deposits but a significant increase in microbial respiration,
substrate induced respiration and enzyme activities like invertase and alkaline phosphatase with increasing application rates
of sewage sludge, compost and sewage sludge mixed with coal sludge. This can be explained by an increase in organic matter
and nutrient content of the soils and an improvement of soil physical properties such as water and nutrient retention capacity.
Additionally it can be assumed, that constituents of the coal admixtures of tertiary deposits can be mineralised or converted
by the soil microorganisms. In the tertiary materials ameliorated with brown coal ash the highest amounts of microbial and
enzyme activities were measured after application of nitrogen-rich sewage sludge or very high amounts of mature compost mainly
consisting of green waste. Compared with sewage sludge the stimulating effects of composted sewage sludge were quite lower
because of organic matter fragmentation and a reduced energy and nutrient supply to soil microorganisms.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
19.
Chromium mobilization and plant availability — the impact of organic complexing ligands 总被引:2,自引:0,他引:2
Pot experiments were conducted to investigate the effect of various organic acids (carboxylic and amino acids) on the uptake
and translocation of root-absorbed trivalent chromium by tomato ( Lycopersicum esculentum) plants grown in sand and soil culture.
Statistically significant increases in chromium accumulation from Cr(III) treated plants in the presence of increasing concentrations
of organic acid suggest the existence of Cr(III) — organic acid interactions in the soil-plant system. However, the amino
acids have been less effective in the mobilization of chromium compared to carboxylic acids. The results are discussed on
the basis of the potential of organic acids to form complexes with Cr(III).
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
20.
Fifty-d-old poplar (Populus deltoides L.) plants were irrigated with 50-200 mM NaCl. 100 and 200 mM NaCl significantly reduced net photosynthetic rate, chlorophyll
and carotenoid contents, leaf area, dry matter accumulation, and harvest index (HI) in all tested poplar clones (Bahar, S7C15,
and WSL22). Clone S7C15 was more tolerant to salinity than the other clones.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献