生物多样性和生态系统功能对全球变化的响应与适应：协同方法

生物多样性与生态系统功能对全球变化的响应与适应是极其复杂的,为了更深入了解和认知,需要融合多学科技术、应用协同方法对其进行研究：其中长期定位观测有助于认识有长时间滞后效应的生态过程或具有重要生态功能的缓慢过程;全球变化实验在自然环境条件下可定量区分各环境因子及其相互作用对生态系统动态的影响;梯度研究可以完善不同时空尺度分析之间的耦合;过程研究则是对野外调查、长期观测或控制实验进行有益补充;这四种研究方法可以镶嵌使用,互补互惠,共同为模型结构的建立和完善提供理论认知,并为模型运行提供参数估算和独立验证数据。模型一方面通过集成各种调查、观测、实验等信息,可以提供强大的模拟分析与预测能力;另一方面它又可以反馈信息来指导各种观测、实验和研究的设计与数据收集,是全球变化研究中必不可少的集成分析工具。     

Aristotle, Copernicus, Bruno: centrality, the principle of movement and the extension of the Universe

This paper¹ studies the different conceptions of both centrality and the principle or starting point of motion in the Universe held by Aristotle and later on by Copernicanism until Kepler and Bruno. According to Aristotle, the true centre of the Universe is the sphere of the fixed stars. This is also the starting point of motion. From this point of view, the diurnal motion is the fundamental one. Our analysis gives pride of place to De caelo II, 10, a chapter of Aristotle’s text which curiously allows an ‘Alpetragian’ reading of the transmission of motion.In Copernicus and the Copernicans, natural centrality is identified with the geometrical centre and, therefore, the Sun is acknowledged as the body through which the Deity acts on the world and it also plays the role of the principle and starting point of cosmic motion. This motion, however, is no longer diurnal motion, but the annual periodical motion of the planets. Within this context, we pose the question of to what extent it is possible to think that, before Kepler, there is a tacit attribution of a dynamic or motive role to the Sun by Copernicus, Rheticus, and Digges.For Bruno, since the Universe is infinite and homogeneous and the relationship of the Deity with it is one of indifferent presence everywhere, the Universe has no absolute centre, for any point is a centre. By the same token, there is no place that enjoys the prerogative of being—as being the seat of God—the motionless principle and starting point of motion.     

Copernicus and Fracastoro: the dedicatory letters to Pope Paul III, the history of astronomy, and the quest for patronage

Copernicus’s De revolutionibus (1543) and Girolamo Fracastoro’s Homocentrica (1538) were both addressed to Pope Paul III (1534-1549). Their dedicatory letters represent a rhetorical exercise in advocating an astronomical reform and an attempt to obtain the papal favour. Following on from studies carried out by Westman (1990) and Barker & Goldstein (2003), this paper deals with cultural, intellectual and scientific motives of both texts, and aims at underlining possible relations between them, such as that Copernicus knew of Fracastoro’s Homocentrica, and that at least part of the rhetorical strategy laid out in De revolutionibus’s dedicatory letter can be read as a sophisticated response to Fracastoro’s arguments.     

Harmony and simplicity: aesthetic virtues and the rise of testability

Copernicus claimed that his system was preferable in part on the grounds of its superior harmony and simplicity, but left very few hints as to what was meant by these terms. Copernicus’s pupil, Rheticus, was more forthcoming. Kepler, influenced by Rheticus, articulated further the nature of the virtues of harmony and simplicity. I argue that these terms are metaphors for the structural features of the Copernican system that make it more able to effectively exploit the available data. So it is a mistake to conclude that early Copernicans could only offer aesthetic or pragmatic arguments; they could and did offer evidential ones as well. Moreover, the evidential arguments they offered parallel current arguments in the philosophical literature.     

薛凤祚科学思想研究的若干问题

关于《历学会通》对哥白尼日心体系的修改问题,科学史工作者提供的证据颇有说服力,应予以认真对待,但尚有探讨余地;明末清初正是中国传统天文历法、数学与占验开始萌发分离动向的时期,薛凤祚是这一潮流的见证人和主要参与者。其占验思想是其科学思想的有机组成部分,应给予宽容而客观的分析和评价;薛凤祚的科学观是其科学思想的核心,研究它须以近代科学观为参照系,如此,方能正确判断其科学观的性质,厘清其中弥足珍贵的近代因素。     

点燃科学圣火的人们

本文摘自作者所著的《物理学与人类文明十六讲》一书,该书由高等教育出版社出版。作者介绍了提出“日心说”的曲折经历,哥白尼、布鲁诺、伽利略等人遭受的迫害,开普勒的不幸人生遭遇,以及他们为真理而献身的精神。