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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.
Abdel-Raheem AM 《Mycopathologia》1997,138(3):163-171
Steralized leaf pieces of eight plants (Eucalyptus rostrata, Phoenix dactylifera, Phragmites australis, Musa nana, Salix subserrata,
Cyperus alopecuroides, Ricinus communis and Eichhornia crassipes) were submerged in the Nile stream. Thirty-nine species of
aquatic hyphomycetes were colonized on the plant leaves. Eucalyptus was the best substratum (30 species) for colonization
by aquatic hyphomycetes. Phoenix (14 species), Phragmites (11 species), Salix (9 species), Musa (8 species), Ricinus and Cyperus
(6 species) were also good substrata for aquatic hyphomycetes colonization. Echhornia (aquatic plant) was not suitable for
aquatic hyphomycetes colonization. Alatospora acuminata, Triscelophorus monosporus and Tetracladium marchalianum were found
to be the major colonizers on all leaf materials. Temperature and dissolved oxygen were the highest physico-chemical parameters
affecting the aquatic hyphomycetes colonization. These results indicate that aquatic hyphomycetes have been shown to be successful
colonizers on plants leaf in river Nile in Egypt as subtropical region.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
3.
We report a further case of peritonitis due to Trichosporon inkin in a patient undergoing continuous ambulatory peritoneal
dialysis. Peritonitis caused by Trichosporon species is reviewed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
4.
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
5.
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
6.
Aphanoascus spp. are keratinophylic fungi occasionally described as etiological agents of tinea-like dermatomycoses. The goal
of this work was to immunochemically characterize somatic and metabolic soluble antigens prepared from 4 species of Aphanoascus.
Electrophoresis in SDS-PAGE gel and immunoblotting with sera from rabbits experimentally immunized with both somatic and metabolic
antigens have shown a similar pattern among the species analyzed. However, some differences were noted between the species
of Aphanoascus. These results suggest the existence of species-specific antigens.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
7.
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
8.
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
9.
Carbonic anhydrase (CA) activity in wheat leaves changed upon leaf dehydration: it decreased at mild stress (relative water
content, RWC, 81 %), but increased at severe water stress (RWC 74 %). Phosphoenopyruvate carboxylase activity was not significantly
affected by these stresses.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
10.
A new species of Pseudotaeniolina, a genus of anamorphic, melanized fungi with meristematic development, is described. The species is compared to morphologically
similar taxa among which are Trimmatostroma and Coniosporium. Its novelty is supported by SSU (small subunit) and ITS (internal transcribed spacer) rDNA sequence data.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
11.
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
12.
A case of deep dermatophytosis in the gluteal region in a male patient successfully treated with terbinafine is described
with its clinical, mycological and histopathological features.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
13.
Pea (Pisum sativum L.) chloroplasts contain water-soluble protein factors. They in vitro activated the rate of Hill reaction
and inhibited the photophosphorylation rate.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
14.
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
15.
Genetic analysis of the content of light-harvesting complexes of thylakoid membranes was accomplished for the first time during
the study of intraspecific variation in photosynthetic characteristics. The existence of genetically determined differences
between genotypes together with positive heterosis in F1 generation was demonstrated.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
16.
In Abelmoschus esculentus L. uniconazole brought about a marked decrease in cadmium-induced loss of chlorophyll and Hill reaction activity, but it
did not completely prevent cadmium toxicity.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
17.
A new species of the family Ancorabolidae Sars, 1909 (Copepoda, Harpacticoida), Arthropsyllus australis sp. n. was collected
1994 during 'Magellan Campaign' of RV 'Victor Hensen' and is described in the present paper. Its inclusion in the genus Arthropsyllus
Sars, 1909 is justified by the diagnostic characters of the genus: lack of any dorsal or dorsolateral well-developed processes,
body slightly depressed dorsoventrally, body somites with lateral epimeres except cephalothorax and last two abdominal somites.
A. australis sp. n. differs from Arthropsyllus serratus Sars, 1909 in the shape of the rostrum, in having moderately-sized
sensilla-bearing dorsal and dorsolateral projections on cephalothorax and body somites, and in several differences on mandible,
maxillule, maxilla and swimming legs.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
18.
Ke B 《Photosynthesis research》2002,73(1-3):207-214
The spectral species P430 and its spectral and kinetic properties are briefly reviewed. Currently available evidence shows
P430 to be the optic-spectral representation of FeS-A/B, the electron acceptor(s) of Photosystem I (PS I).
Retired (formerly with the Charles F. Kettering Research Laboratory, Yellow Springs, Ohio, USA).
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
19.
Walker DA 《Photosynthesis research》2002,73(1-3):51-54
The Hill reaction, its elucidation, and significance is briefly described. Hill oxidants, the role of the methemoglobin reducing
factor and its relation to ferredoxin, and the part played by chloroplast envelopes are discussed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
20.
On the basis of long-term field experiments, the impact is demonstrated of the periodic application of organic fertilizers
on the accumulation of organic matter and the development of the micro-pollutant content of reclaimed loess soils of the Rhineland
lignite mining area under agricultural use. The oldest of these experiments (‘Berrenrath Humus Accumulation Experiment’) was
begun in 1969. The results show that the regular input of organic matter (e.g. manure, waste compost, sewage sludge) favors
the accumulation of soil organic matter (SOM). However, the type of organic material applied seems to be less important to
the long-term accumulation process than the application rate. This is also true for composted and uncomposted manure, if the
decay of organic matter during the composting process is taken into account. Nevertheless, the application of similar amounts
of organic C in the form of manure resulted in a higher accumulation of SOM in a nitrogen-reduced farming system. Depending
on the treatment, accumulation rates were between 0.02 and 0.08% SOM per year with values decreasing with time. From these
results, it is estimated that reclaimed soils will take much longer to reach the former SOM level than was previously assumed.
However, it is important to determine which SOM level is adequate for different soil functions (e.g. production function,
filter and buffer function, transformation function), and whether the young SOM of reclaimed soils has the same properties
as older SOM in undisturbed topsoils. As was expected, long-term fertilization with sewage sludge and waste compost led to
an accumulation of some micro-pollutants in the topsoils treated. Nevertheless, the observed concentrations are quite low
compared to background levels in topsoils of rural regions in North Rhine-Westphalia.
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