Using 18 indica rice varieties with different panicle weight, the photosynthetic characteristics and assimilate's accumulation and transformation in heavy panicle type of rice(HPT)were studied. The results showed ...Using 18 indica rice varieties with different panicle weight, the photosynthetic characteristics and assimilate's accumulation and transformation in heavy panicle type of rice(HPT)were studied. The results showed that the net photosynthetic rate of the flag leaf in HPT after heading was obviously higher than that in medium panicle type(MPT)and light panicle type(LPT). The reason for the high net photosynthetic rate in HPT was the increase of Rubisco activities and chlorophyll content, and keeping high assimilate ability to CO2 under high and low light intensity, high temperature and low CO2 content, and light midday depression and wide adaptability to environmental conditions. The high net photosynthetic rate of HPT might be also the results of its excellent stomatal characteristics and higher total quantity of stomatal opening degrees(stomatal density X stomatal opening degrees). There was a large amount of dry matter production after heading and obvious high assimilate's transformation to panicle in HPT.展开更多
布里顿(Stephen G. Britton)最早运用马克思主义政治经济学,将旅游置于资本主义全球化的社会生产和消费体系中进行批判,回答了旅游到底是什么的问题,为深刻认识旅游发展现象与本质提供了重要的研究路径。作为批判性旅游地理研究的先驱人...布里顿(Stephen G. Britton)最早运用马克思主义政治经济学,将旅游置于资本主义全球化的社会生产和消费体系中进行批判,回答了旅游到底是什么的问题,为深刻认识旅游发展现象与本质提供了重要的研究路径。作为批判性旅游地理研究的先驱人物,他指出旅游是一种重要的资本积累方式,从中可以看到旅游发展如何创造了空间和地方的物质性和社会意义,以及它们的表征如何被纳入到资本积累进程之中。结合布里顿的代表作,本文试图从个体、区域和全球三个层面来理解此核心观点,这体现在旅游的商品属性、产业属性和资本流动的媒介属性。然后梳理后续学者对布里顿思想观点的话题应用并指出对其理论体系的拓展之处,包括旅游的劳工地理、旅游地的空间生产与地方转型、乡村旅游与政治生态3个方面,这明晰了批判性旅游地理研究的主题,回答了布里顿当时的展望性论断——从批判性角度来看,旅游亦是地理学者值得研究的领域,也指引了旅游地理应该由传统的强调空间分析、面向应用而缺乏理论体系的实证主义范式,迈向强调政治经济和权力分析、更加符合旅游地理研究理论化的路径方向。最后辩证指出布里顿思想观点的不足和弥补之处,阐述对中国旅游地理研究的启示,并尝试讨论如何超越旅游的资本维度。展开更多
文摘Using 18 indica rice varieties with different panicle weight, the photosynthetic characteristics and assimilate's accumulation and transformation in heavy panicle type of rice(HPT)were studied. The results showed that the net photosynthetic rate of the flag leaf in HPT after heading was obviously higher than that in medium panicle type(MPT)and light panicle type(LPT). The reason for the high net photosynthetic rate in HPT was the increase of Rubisco activities and chlorophyll content, and keeping high assimilate ability to CO2 under high and low light intensity, high temperature and low CO2 content, and light midday depression and wide adaptability to environmental conditions. The high net photosynthetic rate of HPT might be also the results of its excellent stomatal characteristics and higher total quantity of stomatal opening degrees(stomatal density X stomatal opening degrees). There was a large amount of dry matter production after heading and obvious high assimilate's transformation to panicle in HPT.
文摘布里顿(Stephen G. Britton)最早运用马克思主义政治经济学,将旅游置于资本主义全球化的社会生产和消费体系中进行批判,回答了旅游到底是什么的问题,为深刻认识旅游发展现象与本质提供了重要的研究路径。作为批判性旅游地理研究的先驱人物,他指出旅游是一种重要的资本积累方式,从中可以看到旅游发展如何创造了空间和地方的物质性和社会意义,以及它们的表征如何被纳入到资本积累进程之中。结合布里顿的代表作,本文试图从个体、区域和全球三个层面来理解此核心观点,这体现在旅游的商品属性、产业属性和资本流动的媒介属性。然后梳理后续学者对布里顿思想观点的话题应用并指出对其理论体系的拓展之处,包括旅游的劳工地理、旅游地的空间生产与地方转型、乡村旅游与政治生态3个方面,这明晰了批判性旅游地理研究的主题,回答了布里顿当时的展望性论断——从批判性角度来看,旅游亦是地理学者值得研究的领域,也指引了旅游地理应该由传统的强调空间分析、面向应用而缺乏理论体系的实证主义范式,迈向强调政治经济和权力分析、更加符合旅游地理研究理论化的路径方向。最后辩证指出布里顿思想观点的不足和弥补之处,阐述对中国旅游地理研究的启示,并尝试讨论如何超越旅游的资本维度。