In order to illustrate the change of nitrogen （N） supply capacity after long-term application of manure and chemical fertilizer, as well as to properly manage soil fertility through fertilizer application under the ...In order to illustrate the change of nitrogen （N） supply capacity after long-term application of manure and chemical fertilizer, as well as to properly manage soil fertility through fertilizer application under the soil-climatic conditions of the North China Plain, organic N forms were quantified in the topsoil with different manure and chemical fertilizer treatments in a 15-year fertilizer experiment in a Chinese calcareous alluvial soil. Soil total N （TN） and various organic N forms were significantly influenced by long-term application of chemical fertilizer and manure. TN, total hydrolysable N, acid-lnsoluble N, amino acid N and ammonium N in the soil increased significantly （P 〈 0.05） with increasing manure and fertilizer N rates, but were not influenced by increasing P rates. Also, application of manure or N fertilizer or P fertilizer did not significantly influence either the quantity of amino sugar N or its proportion of TN. Application of manure significantly increased （P 〈 0.05） hydrolysable unknown N, but adding N or P did not. In addition, application of manure or N fertilizer or P fertilizer did not significantly influence the proportions of different soil organic N forms.展开更多
Two wild mushrooms frequently consumed in Jordan were collected form Jordan forests in spring 2012. Each sample was studied in the lab by taking measurements on the morphological structures of the cap, stem, and recor...Two wild mushrooms frequently consumed in Jordan were collected form Jordan forests in spring 2012. Each sample was studied in the lab by taking measurements on the morphological structures of the cap, stem, and recording gill＇s color, shape and dimensions. Also smell and taste for each fruiting structure were taken in consideration. Spore print for each sample was also defined. Spores of each mushroom were microscopically tested and measured. These mushrooms were identified as Pleurotus eryngi and Tricholoma terreum. The two mushrooms were evaluated for their physical properties, chemical and mineral composition. Contents of Ca, Na, K, Zn, Mn, Cu, Fe and Mg were determined. For each mushroom species two mixed samples were analyzed. Nitrogen content was detected with Kjeldahl method and protein content （%） was calculated by multiplying nitrogen content with the factor 4.38. The highest protein content calculated on oven dry weight basis was found in Pleurotus eryngi which was around 30.6%, while Tricholoma terreum contained lowest protein content （17.4%）. Pleurotus eryngi accumulated trace elements at high ratios as for P, Ca and Na 0.99%, 0.65% and 0.57% respectively while Tricholoma terreum contained more K （5.1%） than the other wild mushroom. Total soluble carbohydrates （50.8%）, crude fiber （13.4%） and ash （12.2%） percentages were higher in Tricholoma terreum than in Pleurotus eryngi.展开更多
基金Project supported by the National Natural Science Foundation of China (Nos. 30390080 and 30370287).
文摘In order to illustrate the change of nitrogen （N） supply capacity after long-term application of manure and chemical fertilizer, as well as to properly manage soil fertility through fertilizer application under the soil-climatic conditions of the North China Plain, organic N forms were quantified in the topsoil with different manure and chemical fertilizer treatments in a 15-year fertilizer experiment in a Chinese calcareous alluvial soil. Soil total N （TN） and various organic N forms were significantly influenced by long-term application of chemical fertilizer and manure. TN, total hydrolysable N, acid-lnsoluble N, amino acid N and ammonium N in the soil increased significantly （P 〈 0.05） with increasing manure and fertilizer N rates, but were not influenced by increasing P rates. Also, application of manure or N fertilizer or P fertilizer did not significantly influence either the quantity of amino sugar N or its proportion of TN. Application of manure significantly increased （P 〈 0.05） hydrolysable unknown N, but adding N or P did not. In addition, application of manure or N fertilizer or P fertilizer did not significantly influence the proportions of different soil organic N forms.
文摘Two wild mushrooms frequently consumed in Jordan were collected form Jordan forests in spring 2012. Each sample was studied in the lab by taking measurements on the morphological structures of the cap, stem, and recording gill＇s color, shape and dimensions. Also smell and taste for each fruiting structure were taken in consideration. Spore print for each sample was also defined. Spores of each mushroom were microscopically tested and measured. These mushrooms were identified as Pleurotus eryngi and Tricholoma terreum. The two mushrooms were evaluated for their physical properties, chemical and mineral composition. Contents of Ca, Na, K, Zn, Mn, Cu, Fe and Mg were determined. For each mushroom species two mixed samples were analyzed. Nitrogen content was detected with Kjeldahl method and protein content （%） was calculated by multiplying nitrogen content with the factor 4.38. The highest protein content calculated on oven dry weight basis was found in Pleurotus eryngi which was around 30.6%, while Tricholoma terreum contained lowest protein content （17.4%）. Pleurotus eryngi accumulated trace elements at high ratios as for P, Ca and Na 0.99%, 0.65% and 0.57% respectively while Tricholoma terreum contained more K （5.1%） than the other wild mushroom. Total soluble carbohydrates （50.8%）, crude fiber （13.4%） and ash （12.2%） percentages were higher in Tricholoma terreum than in Pleurotus eryngi.
