A new diverse assemblage of microorganisms has been discovered in black bedded, nodular and lenticular cherts and dark chert of domical stromatolites in dolostone of the Gaoyuzhuang Formation in Lingqiu County, northe...A new diverse assemblage of microorganisms has been discovered in black bedded, nodular and lenticular cherts and dark chert of domical stromatolites in dolostone of the Gaoyuzhuang Formation in Lingqiu County, northern Taihang Mountains. The geologic relationships, biostratigraphic correlations, and available radiometric age determinations place the age of the Gaoyuzhuang Formation at approximately 1400-1600 million years in age. Eight new species, three unnamed species, and two emended genera of oscillatoriacean, nostocacean, and chroococcacean cyanobacteria are described. These data coupled with reports of others indicate that the diversity of taxa in the Gaoyuzhuang Formation reaches 100 species. The Gaoyuzhuang Formation contains one of the richest Mesoproterozoic communities of microfossils. The following new and emended taxa are described: Oscillatoriaceae: Eophormidium orculiformis sp. nov., E, sp,, Siphonophycus caudataceous sp, nov., Palaeolyngbya complanata sp, nov., P. capitata sp. nov., P. sp. and Oscillatoriopsis sp.. Nostocaceae: Veteronostocale vaginata sp, nov.. Chroococcaceae: Maculosphaera giganta sp. nov. and Gloeotheceopsis grandis sp. nov. Incertae sedis: Myxcxoccoides limpida sp. nov.展开更多
Soil salinity has been considered a brutal environmental factor for decreasing crop yield due to the accumulation of excessive sodium salts in soil under arid and semi-arid region of the world. This study tries to add...Soil salinity has been considered a brutal environmental factor for decreasing crop yield due to the accumulation of excessive sodium salts in soil under arid and semi-arid region of the world. This study tries to address the potential use of biochar. An organic matter rich material, used to reclaim salt-stressed soil in order to enhance crop production in dry croplands as well as to increase soil organic carbon （SOC） and to improve soil fertility. In this regard, a field experiment for two years was conducted in a moderately salt-stressed soil of Central China with wheat-maize cropping system. The soil was amended with biochar composted with poultry manure （BPC） at 12 t/ha with diluted pyroligneous solution （PS） at 0.15 t/ha a week before sowing of crop. Results showed significant improvement in soil physical properties, soil nutrient content with reduction of sodium salts and soil pH by amendment of BPC-PS1 and BPC-PS2 over the experimental control salt-stressed cropland. Furthermore, wheat and maize grain yield, nitrogen, phosphorous potassium and K/Na ratio increased while sodium decreased with the application of BPC-PS amendment in wheat and maize grain. This study concluded that the biochar amendment in conjunction with PS greatly improved SOC storage, crop nutrient uptake and soil fertility. Thus, waste treatment of crop straw and poultry manure compost as biochar could be combined to alleviate salt stress and improve crop production in the vast area of arid and semi-arid regions of the world.展开更多
文摘A new diverse assemblage of microorganisms has been discovered in black bedded, nodular and lenticular cherts and dark chert of domical stromatolites in dolostone of the Gaoyuzhuang Formation in Lingqiu County, northern Taihang Mountains. The geologic relationships, biostratigraphic correlations, and available radiometric age determinations place the age of the Gaoyuzhuang Formation at approximately 1400-1600 million years in age. Eight new species, three unnamed species, and two emended genera of oscillatoriacean, nostocacean, and chroococcacean cyanobacteria are described. These data coupled with reports of others indicate that the diversity of taxa in the Gaoyuzhuang Formation reaches 100 species. The Gaoyuzhuang Formation contains one of the richest Mesoproterozoic communities of microfossils. The following new and emended taxa are described: Oscillatoriaceae: Eophormidium orculiformis sp. nov., E, sp,, Siphonophycus caudataceous sp, nov., Palaeolyngbya complanata sp, nov., P. capitata sp. nov., P. sp. and Oscillatoriopsis sp.. Nostocaceae: Veteronostocale vaginata sp, nov.. Chroococcaceae: Maculosphaera giganta sp. nov. and Gloeotheceopsis grandis sp. nov. Incertae sedis: Myxcxoccoides limpida sp. nov.
文摘Soil salinity has been considered a brutal environmental factor for decreasing crop yield due to the accumulation of excessive sodium salts in soil under arid and semi-arid region of the world. This study tries to address the potential use of biochar. An organic matter rich material, used to reclaim salt-stressed soil in order to enhance crop production in dry croplands as well as to increase soil organic carbon （SOC） and to improve soil fertility. In this regard, a field experiment for two years was conducted in a moderately salt-stressed soil of Central China with wheat-maize cropping system. The soil was amended with biochar composted with poultry manure （BPC） at 12 t/ha with diluted pyroligneous solution （PS） at 0.15 t/ha a week before sowing of crop. Results showed significant improvement in soil physical properties, soil nutrient content with reduction of sodium salts and soil pH by amendment of BPC-PS1 and BPC-PS2 over the experimental control salt-stressed cropland. Furthermore, wheat and maize grain yield, nitrogen, phosphorous potassium and K/Na ratio increased while sodium decreased with the application of BPC-PS amendment in wheat and maize grain. This study concluded that the biochar amendment in conjunction with PS greatly improved SOC storage, crop nutrient uptake and soil fertility. Thus, waste treatment of crop straw and poultry manure compost as biochar could be combined to alleviate salt stress and improve crop production in the vast area of arid and semi-arid regions of the world.
