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Pierluigi Genevini Fabrizio Adani Adrie H.M. Veeken Klass G.J. Nierop Barbara Scaglia Cor Dijkema 《Soil Science and Plant Nutrition》2013,59(2):143-150
Humic acid-like (HA-like) and core-humic acid-like (core-HA-like) were characterized during the high-rate composting process by CP-MAS 13C NMR, pyrolysis-gas chromatography (GC)/mass spectrometry (MS), and elemental analysis. Results obtained indicated that humification proceeded through a relative concentration of aromatic fractions due to the faster degradation of the O-alkyl and alkyl fractions. Core-HA-like, after purification of the parent material, showed a large reduction of the O-alkyl fraction in terms of HA-like. We concluded that HA-like consisted of refractory organic molecules, such as lignin and biopolymers, which formed a stable structure (core-HA-like) coated with degradable material associated with the core by weak physical association, ether or ester bounds. 相似文献
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Houwing Erik‐Jan Houwing Erik-Jan van Duin Willem E. Waaij Yvonne Smit-van der Dijkema Kees S. Terwindt Joost H.J. 《Mangroves and Salt Marshes》1999,3(4):197-206
During the last two decades a decrease of salt marsh area of at least 6% was found along the mainland coast of the Dutch Wadden Sea. However, it was not clear what determined the seaward boundary of the pioneer vegetation in this area. In the period 1993–1995, abiotic and biological variables were monitored along a transect from the mudflat to the low salt marsh in two sites, the Negenboerenpolder and the Noordpolder. At the Negenboerenpolder site the pioneer zone extended further from the dike and had a dense cover with vegetation when compared to the Noordpolder site. The observed difference in extension of the pioneer zone could not be attributed to differences in tidal frequency, sedimentation rate or nutrient availability. During the winter a dramatic loss in seed numbers was found at both sites. This loss decreased from mudflat to low marsh. The mud/sand ratio, on the other hand, increased from mudflat to low marsh and was higher in the Negenboerenpolder. The shear strength of the top soil layer measured with an insitu erosion flume was correlated to the mud/sand ratio and increased with an increasing mud content of the soil. The strength of the soil seems to be the key factor for the settlement and survival of Salicornia dolichostachya in the pioneer zone. 相似文献
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Ir L. R. Dijkema 《European journal of plant pathology / European Foundation for Plant Pathology》1947,53(1):16-18
Summary In the Wieringermeerpolder reclaimed about 1930, some cases of severe damage caused by the Oats Nematode (Heterodera avenae
Filipjev) have been observed since 1943. In one of the cases mentioned (I) 8×cereals have been grown in 13 years, viz. 3×oats, 3×wheat, 1×barley and 1×rye. In another case (II) 8×cereals occurred in 12 years, viz. 3×oats, 3×wheat and 2×barley. It is obvious that this crop rotation promotes the occurrence of the Oats Nematode. A crop rotation with less cereals is recommended.
Voorlichtingsdienst in de Wieringermeer 相似文献
Voorlichtingsdienst in de Wieringermeer 相似文献
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