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261.
Einfluß unterschiedlicher Düngung auf pH,N, C und die Gehalte an CAL-extrahierbarem K und P im Boden
Christian Richter Burkhard Heiligtag Reinhard Schmidt Eberhard Klsch 《植物养料与土壤学杂志》1997,160(1):107-111
Influence of different fertilization on pH, N, C and CAL-extractable K and P in the soil The influence of different fertilization (mineral fertilizer, different kinds and quantities of farmyard manure and biocompost, horn meal) on soil properties was studied during 8 years of cultivation. The plots were planted and harvested as practised under local farming conditions. The pH of the non-fertilized plots decreased from 5.84 to 5.69, while it was increased by fertilization with farmyard manure or biocompost. Nt in the soil was not influenced by different fertilization. Ct was increased by high biocompost application, stayed constant on the other fertilized plots but decreased on the nonfertilized plots from 1.08 to 0.99%. Without fertilization, plant available nutrients were diminished from 7.3 to 4.3 mg P(CAL) 100 g?1 and from 22.5 to 13.9 mg K(CAL) 100 g?1. However, if the plots were fertilized with mineral or organic fertilizer, the nutrient content remained on the initial level. Storing farmyard manure under roof or covering with straw or polyethylene sheet did not affect the criteria of soil studied. 相似文献
262.
Jürgen Schultze-Motel Reinhard Fritsch Karl Hammer Peter Hanelt Joachim Kruse Helga I. Maass Harald Ohle Klaus Pistrick 《Genetic Resources and Crop Evolution》1988,36(3):571-592
Summary Important papers on taxonomy and evolution of cultivated plants published in 1986 and 1987 were compiled and briefly discussed.
Taxonomic und Evolution der Kulturpflanzen: Litcraturübersicht 1986/1987
Zusammenfassung Wichtige Arbciton übot Taxonomie und Evolution der Kulturpflanzen aus den Jahren 1986 und 1987 wuzden zusammengestolit und kurz kommentiert.
: . 1986–1987
, 1986 1987 . .相似文献
263.
Reinhard M. Fritsch Farideh Matin Manfred Klaas 《Genetic Resources and Crop Evolution》2001,48(4):401-408
A wild onion species from Karaj valley east of Tehran istaxonomically described as Allium asarense R. M.Fritsch et Matin. Sharing the bubble-like inflated lower scapewith A. vavilovii, the newspecies differs by semi-cylindrical leaves and small flowerswith translucent greenish-yellow tepals from all other knownspecies of Allium sect.Cepa. Molecular data suggest a closerelationship to A. cepa(but to a lesser degree than A.vavilovii) and indicate a still weakerphylogenetic connection of A.oschaninii to the common onion. The questionabout the possible wild ancestor of A.cepa is discussed against this background, and akey for determination of the Oschaninii-alliance of sect.Cepa is presented. 相似文献
264.
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266.
ER tubules mark sites of mitochondrial division 总被引:1,自引:0,他引:1
Friedman JR Lackner LL West M DiBenedetto JR Nunnari J Voeltz GK 《Science (New York, N.Y.)》2011,334(6054):358-362
Mitochondrial structure and distribution are regulated by division and fusion events. Mitochondrial division is regulated by Dnm1/Drp1, a dynamin-related protein that forms helices around mitochondria to mediate fission. Little is known about what determines sites of mitochondrial fission within the mitochondrial network. The endoplasmic reticulum (ER) and mitochondria exhibit tightly coupled dynamics and have extensive contacts. We tested whether ER plays a role in mitochondrial division. We found that mitochondrial division occurred at positions where ER tubules contacted mitochondria and mediated constriction before Drp1 recruitment. Thus, ER tubules may play an active role in defining the position of mitochondrial division sites. 相似文献
267.
Phosphorus pools in soil after land conversion from silvopasture to arable and grassland use 下载免费PDF全文
Anna Slazak Dirk Freese Eduardo S. Matos Seth Nii‐Annang Reinhard F. Hüttl 《植物养料与土壤学杂志》2014,177(2):159-167
Differences in soil P among silvopasture, grassland, and arable lands have been well established. Nevertheless, most of the reports compare soil properties under long‐term sites. Thus, there exists little information on the effect of the conversion of silvopasture to arable or grassland use on soil P pools. The objective of the study was to determine the impact of converting silvopasture system (SP) into arable cropping and grassland system on the distribution of P pools and potential P bioavailability. We compared the following systems: SP system, SP converted to arable cropland (SP‐AL), SP converted to grassland (SP‐GL), and for comparative purposes, a long‐term arable cropland (AL). The P fractionation was performed by a sequential extraction scheme, using acid and alkaline extractants on samples collected from the 0–10 and 10–20 cm soil layers. It was assumed that the large variations in soil‐P fractionations are caused by the different management practices associated with land conversion. The results of P fractionation showed a dominance of calcium‐bound P, HCl‐extractable Pi constituted up to 36% of the soil total P (TP). However, the type of land use did not affect this P fraction. On the other hand, the reduction in labile‐Pi and NaOH‐Pi fractions observed at the SP‐AL site may have led to the decline in readily available P. The soil total organic P (TPo) content was 8% and 17% lower at SP‐AL compared to SP and SP‐GL site, respectively. Labile organic‐P (labile‐Po) content was markedly higher at SP site compared to arable soils, and was ≈ 10% of TPo. The NaOH‐Po constituted the highest fraction of the organic‐P pool (55%–79% of TPo) across all the study systems, and was positively correlated with TPo (p < 0.01). The study indicates that conversion of SP system in temperate regions to arable cropping with conventional tillage seems to result in the reduction of P availability compared to SP, indicating SP as an important land‐use practice. 相似文献
268.
Enhanced phytoextraction of heavy metals using chelating agents and agricultural crops is widely discussed as a remediation technique for agricultural soils contaminated with low mobile heavy metals. In this study, phytoextraction efficiency of Zea mays after single and split applications of EDTA was tested on the laboratory and the field scale. EDTA effectively increased the mobility of target heavy metals (Pb and Cd) in the soil solution. Split applications provided generally lower water-soluble levels of Pb and Cd both in the pot and the field experiment. Therefore, the risk of groundwater contamination may be reduced after split applications. Higher Pb and Cd mobilisation after single applications increased plant stress, phytotoxicity and reduced plant dry above-ground biomass production compared to corresponding split doses. Single doses enhanced plant uptake of Pb and Cd and the phytoremediation efficiency compared to corresponding split doses. Results of plant dry above-ground biomass and heavy metal uptake obtained from the pot experiment could be to some extent verified in the field experiment. Plant uptake of Pb and Cd was lower and biomass production dropped after EDTA additions in the field experiment. Remediation factors in the field experiment were in general significantly lower than in the pot experiment mainly due to the much higher mass of soil per plant under field conditions. This highlights the limitations when going from the lab to the field scale. The low phytoremediation efficiency in the field and the mobilisation of high amounts of Pb and Cd down the soil profile may make the use of EDTA and Z. mays not suitable for the remediation of severely heavy metal contaminated soils in a reasonable time frame and may result in substantial groundwater pollution under used crop management. 相似文献
269.
Reinhard Well Heinz Flessa Lu Xing Ju Xiaotang Volker Rmheld 《Soil biology & biochemistry》2008,40(9):2416
Soils represent the major source of the atmospheric greenhouse gas nitrous oxide (N2O) and there is a need to better constrain the total global flux and the relative contribution of the microbial source processes. The aim of our study was to determine variability and control of the isotopic fingerprint of N2O fluxes following NH4+-fertilization and dominated by nitrification. We conducted a microcosm study with three arable soils fertilized with 0–140 mg NH4+–N kg−1. Fractions of N2O derived from nitrification and denitrification were determined in parallel experiments using the 15N tracer and acetylene inhibition techniques or by comparison with unfertilized treatments. Soils were incubated for 3–10 days at low moisture (30–55% water-filled pore space) in order to establish conditions favoring nitrification. Dual isotope and isotopomer ratios of emitted N2O were determined by mass spectrometric analysis of δ18O, average δ15N (δ15Nbulk) and 15N site preference (SP = difference in δ15N between the central and peripheral N positions of the asymmetric N2O molecule). N2O originated mainly from nitrification (>80%) in all treatments and the proportion of NH4+ nitrified that was lost as N2O ranged between 0.07 and 0.45%. δ18O and SP of N2O fluxes ranged from 15 to 28.4‰ and from 13.9 to 29.8‰, respectively. These ranges overlapped with isotopic signatures of N2O from denitrification reported previously. There was a negative correlation between SP and δ18O which is opposite to reported trends in N2O from denitrification. Variation of average 15N signatures of N2O (δ15Nbulk) did not supply process information, apparently because a strong shift in precursor signatures masked process-specific effects on δ15Nbulk. Maximum SP of total N2O fluxes and of nitrification fluxes was close to reported SP of N2O from NH4+ or NH2OH conversion by autotrophic nitrifiers, suggesting that SP close to 30‰ is typical for autotrophic nitrification in soils following NH4+-fertilization. The results suggest that the δ18O/SP fingerprint of N2O might be used as a new indicator of the dominant source process of N2O fluxes in soils. 相似文献
270.
Sree Usha Bauer Heidi Fuerhacker Maria Ellinger Reinhard Schmidt Heidrun Puxbaum Hans 《Water, air, and soil pollution》2000,124(1-2):177-186
Hydrocarbons emissions were measured from an aerationtank of a municipal wastewater treatment pilot plant. The collected off-gas samples werecharacterised for C2–C7 hydrocarbons usingGC-FID analytical technique while the total volatileorganic compounds (TVOC) were measured using acontinuous hydrocarbon gas analyser. Approximately,the estimated emission rates for 1 m3 of wastewaterfrom this aeration tank were 5 mgC of C2–C7hydrocarbons, and an average of 7 gC of TVOC. Withexception to toluene, all other measured hydrocarbonsare emitted less than 1 mgC day-1. The results supportthe view that a significant reduction in annualemissions of hydrocarbons from wastewater treatmentplants in Vienna has taken place. 相似文献