In order to assess the climatical and ecological effect which returned the farmland to pasture or forest, the vegetation and crop in Northwest China with suitable threshold value were classified in this experiment by ...In order to assess the climatical and ecological effect which returned the farmland to pasture or forest, the vegetation and crop in Northwest China with suitable threshold value were classified in this experiment by using multi-temporal SPOT/VEGETATION dada and combing supervised classification with unsupervised classification. Compared with the data from Statistical Department and actual investigation, the precision of the classified result was above 85%.展开更多
[Objective] The aim was to study the dynamic variation of vegetation and its response to economic factors in the border area of Heilongjiang Province.[Method] Based on SPOT Vegetation NDVI data in each 10 days from 19...[Objective] The aim was to study the dynamic variation of vegetation and its response to economic factors in the border area of Heilongjiang Province.[Method] Based on SPOT Vegetation NDVI data in each 10 days from 1998 to 2007,the dynamic variation of vegetation in the border area of Heilongjiang Province in recent 10 years was studied,and the response of vegetation variation to economic factors was analyzed in the paper.[Result] On the whole,vegetation coverage was high in the border area of Heilongjiang Province from 1998 to 2007,and showed increasing trend.Except for parts of Huma County showing degrading trend,the whole vegetation condition in the border area of Heilongjiang Province was basically constant or improved,and the region with constant vegetation accounted for 71.00%,while the region with slight improved vegetation occupied 26.81%.Meanwhile,vegetation index and GDP increased on the whole from 1998 to 2007,but there was no complete consistency in their trends.In addition,MNDVI was significantly positively correlated with the average salary of local workers (P<0.01),but significantly negatively correlated with farmland area (P<0.01),and the negative correlation was delayed,that is to say,the decrease of farmland area in the first year would affect MNDVI in the second and third year.[Conclusion] The study could provide scientific references for the establishment of policies about economic development and ecological environment in Heilongjiang River basin.展开更多
To assist with rapid screening for rice blast resistance as a precursor in a breeding program, the susceptibility to rice blast of 13 rice genotypes from Australia was evaluated in May to June 2013 using three distinc...To assist with rapid screening for rice blast resistance as a precursor in a breeding program, the susceptibility to rice blast of 13 rice genotypes from Australia was evaluated in May to June 2013 using three distinct inoculation methods（spot, filter paper and standard methods） at seedling, vegetative and reproductive stages. The results revealed that the spot and filter paper inoculation methods were successful in discerning susceptibility to the rice blast disease（P ≤ 0.05）. Disease susceptibility declined significantly from the vegetative to reproductive stages. The standard method was conducted at three different stages for pot plants grown inside the mist house. However, low temperatures did not produce disease symptoms except in a few genotypes. Among the 13 rice genotypes screened, AAT9 expressed a highly resistant response, and AAT4, AAT6, AAT10, AAT11, AAT13, AAT17 and AAT18 expressed resistance at various stages. The results will be useful for selecting elite genotypes for disease tolerance where rice blast is prevalent. In addition, the resistant genotypes can serve as a gene pool used in breeding programmes to develop new resistant genotypes.展开更多
基金Supported by the National Natural Science Foundation of China(No.40675071)~~
文摘In order to assess the climatical and ecological effect which returned the farmland to pasture or forest, the vegetation and crop in Northwest China with suitable threshold value were classified in this experiment by using multi-temporal SPOT/VEGETATION dada and combing supervised classification with unsupervised classification. Compared with the data from Statistical Department and actual investigation, the precision of the classified result was above 85%.
基金Supported by Special Fund for Scientific Research Fee of Central Higher Education ( 507275871)
文摘[Objective] The aim was to study the dynamic variation of vegetation and its response to economic factors in the border area of Heilongjiang Province.[Method] Based on SPOT Vegetation NDVI data in each 10 days from 1998 to 2007,the dynamic variation of vegetation in the border area of Heilongjiang Province in recent 10 years was studied,and the response of vegetation variation to economic factors was analyzed in the paper.[Result] On the whole,vegetation coverage was high in the border area of Heilongjiang Province from 1998 to 2007,and showed increasing trend.Except for parts of Huma County showing degrading trend,the whole vegetation condition in the border area of Heilongjiang Province was basically constant or improved,and the region with constant vegetation accounted for 71.00%,while the region with slight improved vegetation occupied 26.81%.Meanwhile,vegetation index and GDP increased on the whole from 1998 to 2007,but there was no complete consistency in their trends.In addition,MNDVI was significantly positively correlated with the average salary of local workers (P<0.01),but significantly negatively correlated with farmland area (P<0.01),and the negative correlation was delayed,that is to say,the decrease of farmland area in the first year would affect MNDVI in the second and third year.[Conclusion] The study could provide scientific references for the establishment of policies about economic development and ecological environment in Heilongjiang River basin.
文摘To assist with rapid screening for rice blast resistance as a precursor in a breeding program, the susceptibility to rice blast of 13 rice genotypes from Australia was evaluated in May to June 2013 using three distinct inoculation methods（spot, filter paper and standard methods） at seedling, vegetative and reproductive stages. The results revealed that the spot and filter paper inoculation methods were successful in discerning susceptibility to the rice blast disease（P ≤ 0.05）. Disease susceptibility declined significantly from the vegetative to reproductive stages. The standard method was conducted at three different stages for pot plants grown inside the mist house. However, low temperatures did not produce disease symptoms except in a few genotypes. Among the 13 rice genotypes screened, AAT9 expressed a highly resistant response, and AAT4, AAT6, AAT10, AAT11, AAT13, AAT17 and AAT18 expressed resistance at various stages. The results will be useful for selecting elite genotypes for disease tolerance where rice blast is prevalent. In addition, the resistant genotypes can serve as a gene pool used in breeding programmes to develop new resistant genotypes.
