The article established the HDRICE model by modifying the structure of the ORYZA1 model and revising its parameters by field experiments. The HDRICE model consists of the modules of morphological development of rice, ...The article established the HDRICE model by modifying the structure of the ORYZA1 model and revising its parameters by field experiments. The HDRICE model consists of the modules of morphological development of rice, daily dry matter accumulation and partitioning, daily CO2 assimilation of the canopy, leaf area, and tiller development. The model preferably simulated the dynamic rice development because of the thorough integration of the effects of temperature and light on the rates of rice development, photosynthesis, respiration, and. other ecophysiological processes. In addition, this model has attainable grain yield in the test experiment that showed the potential yield of cultivar Xieyou 46 ranged from 11 to 13 tons ha-~. Besides, the model was used to optimize the combinations of the transplanting date, seedling age and density for cultivar Xieyou 46 at Jinhua area, and the population quantitative indices to attain the potential yield such as maximum stems, effective panicles, filled grain number/leaf area, and so on. The result showed that the combination of transplanting date on July 25, seedling age of 35 days and base seedling density of 1.33 x 106ha-1 is the optimum combination for the second hybrid rice production in Jinhua County, China. And the maximum stems, the effective panicles, the filled grain per panicle, the peak of optimum LAI, LAI in later filling stage, and the filled grain number/leaf were 6.03×10^6ha, 3.99×10^6ha, 119.2, 8.59, 5-6, and 0.64, respectively.展开更多
Previous studies have suggested that urbanization presents a major threat to anuran populations. However, very few studies have looked at the relationship between urbanization and anuran body condition. We investigate...Previous studies have suggested that urbanization presents a major threat to anuran populations. However, very few studies have looked at the relationship between urbanization and anuran body condition. We investigated whether the distribution and body condition of the rice-paddy frog（Fejervarya multistriata） and gold-striped pond frog（Pelophylax plancyi） are influenced by increasing urbanization in Shanghai, China. Four study sites with six indicators of the major land-cover types were scored to indicate their position on an urbanization gradient. We found that both the density and body condition of F. multistriata declined significantly along this gradient. Although we observed a significant difference in body condition of P. plancyi among study sites with different degrees of urbanization, we did not find any corresponding significant differences in population density. Our results indicate that both the densities and body condition of these two anuran species show a negative relationship with increasing urbanization, but that the density of P. plancyi was only slightly affected in Shanghai.展开更多
基金supported by the National Natural Science Foundation of China(69673044).
文摘The article established the HDRICE model by modifying the structure of the ORYZA1 model and revising its parameters by field experiments. The HDRICE model consists of the modules of morphological development of rice, daily dry matter accumulation and partitioning, daily CO2 assimilation of the canopy, leaf area, and tiller development. The model preferably simulated the dynamic rice development because of the thorough integration of the effects of temperature and light on the rates of rice development, photosynthesis, respiration, and. other ecophysiological processes. In addition, this model has attainable grain yield in the test experiment that showed the potential yield of cultivar Xieyou 46 ranged from 11 to 13 tons ha-~. Besides, the model was used to optimize the combinations of the transplanting date, seedling age and density for cultivar Xieyou 46 at Jinhua area, and the population quantitative indices to attain the potential yield such as maximum stems, effective panicles, filled grain number/leaf area, and so on. The result showed that the combination of transplanting date on July 25, seedling age of 35 days and base seedling density of 1.33 x 106ha-1 is the optimum combination for the second hybrid rice production in Jinhua County, China. And the maximum stems, the effective panicles, the filled grain per panicle, the peak of optimum LAI, LAI in later filling stage, and the filled grain number/leaf were 6.03×10^6ha, 3.99×10^6ha, 119.2, 8.59, 5-6, and 0.64, respectively.
基金supported financially by the Shanghai Landscaping and City Appearance Administrative Bureau Project (Grant No. F131508)
文摘Previous studies have suggested that urbanization presents a major threat to anuran populations. However, very few studies have looked at the relationship between urbanization and anuran body condition. We investigated whether the distribution and body condition of the rice-paddy frog（Fejervarya multistriata） and gold-striped pond frog（Pelophylax plancyi） are influenced by increasing urbanization in Shanghai, China. Four study sites with six indicators of the major land-cover types were scored to indicate their position on an urbanization gradient. We found that both the density and body condition of F. multistriata declined significantly along this gradient. Although we observed a significant difference in body condition of P. plancyi among study sites with different degrees of urbanization, we did not find any corresponding significant differences in population density. Our results indicate that both the densities and body condition of these two anuran species show a negative relationship with increasing urbanization, but that the density of P. plancyi was only slightly affected in Shanghai.
