20世纪初叶以来中国地理学研究范式特征与发展

“范式”一词于20世纪70年代由库恩基于科学哲学提出,并逐渐为科学界接受。同时,各学科学者借用库恩的“范式”概念和“研究程序”思想而构建出本学科的研究范式。因此,使得各学科间的研究范式既具有相对独立性又存在联系性。地理学也因此形成自己的研究范式。中国近现代地理学作为世界地理学的重要组成部分,深受其思想与方法的影响。因此,系统地认识20世纪初叶以来我国地理学研究范式的发展历程十分必要。采用“历史”与“逻辑”统一的原则对地理学研究范式的含义与意义及我国地理学研究范式历史的认识进行研究得出：中国地理学经历了区域因果关系范式到空间范式的继承与转变;我国近现代地理学范式的发展始终是“显范式”（冠予“范式”一词的研究方法）与“潜范式”（未冠予“范式”一词的研究方法）并存发展的;我国人文地理学研究范式与应用多以“显范式”为主,自然地理学多以“潜范式”为主;所有地理学研究范式都遵循地理学空间思想指导;未来地理学研究范式将朝向定量化、技术化、空间化、社会性和文化性方向及格局、过程、机制及模拟发展,朝向科学第四范式迈进。     

珠江口表层沉积物nirS型反硝化微生物多样性

本研究以nirS基因为分子标记,将PCR、克隆文库构建与测序和典范对应分析相结合,对珠江口表层沉积物nirS型反硝化微生物的群落多样性进行了研究。3个站位共获得180个nirS基因克隆子,隶属于62个OTUs,氨基酸序列的相似性在50%—100%之间。各站位OTU分布格局差异明显,范围在19—33之间,表现出高度的多样性。系统进化分析表明,62个OTUs形成了5个类群,分别与河口、海洋沉积物、海岸养殖排放废水、富营养化海湾及海水养殖沉积物等的反硝化微生物聚类在一起,表明珠江口作为海淡水交汇区具有独特的反硝化微生物群落分布格局,同时也指示了珠江口氮污染及富营养化程度。典范对应分析结果表明,盐度、氮相关营养盐水平(PON/TN、NH4-N、NO-N和NO-N)可能是影响其分布格局的重要因素。     

海蜇(Rhopilema esculenta)浮浪幼虫及早期螅状体摄食行为的研究

采用对比实验与显微观察的方法,对海蜇浮浪幼虫及早期螅状体的摄食行为进行了研究。结果表明,海蜇浮浪幼虫期不摄食外界食物;浮浪幼虫附着变态发育成海蜇螅状体1d后,开始摄食其它浮浪幼虫,螅状体发育到第3天摄食能力迅速增强,能够捕食卤虫无节幼体。海蜇早期螅状体的捕食实验结果表明,早期螅状体开始捕食主要受两方面影响,一方面是口的发育,另一方面是刺细胞的发育。     

基于两种数据集的全球SST变化趋势的对比研究

分别利用了来自NOAA和Hadley中心的SST(Sea Surface Temperature)资料,分析了全球海域每个网格点上SST的变化趋势,并将两种资料分析的结果进行比较。研究发现:近150a期间,全球大部分海域的SST以0.003℃.a-1左右的速度显著性逐年线性递增,仅在格陵兰南部海域和两极部分海域呈显著的逐年线性递减趋势;NOAA的SST变化趋势的区域性差异比Hadley的SST明显,但后者变化趋势的强度稍大于前者;不同海域SST的逐年变化趋势由不同的季节主导;在1910年为近150a来SST的最低点,之后缓慢上升,在1942年附近达到1个相对高点,而后略有下降,但很快又恢复上升趋势,上升趋势一直延续至今。     

阿克达拉大气本底站气流轨迹模拟研究

 利用1994—2002年NCEP再分析资料和HYSPLIT v4.7轨迹模式模拟了阿克达拉大气本底站的气团三维后向轨迹;采用簇分析方法对计算出的数千条后向轨迹进行了聚类归并,得到反映气流轨迹主要特征的数条轨迹;按垂直层次和季节分别作图,并进行分析。主要研究了该站近9 a来不同季节距地面100 m和1 000 m的近地面边界层气流轨迹的特征、各方向轨迹出现的频数及当地天气形势和地面天气系统与气流轨迹的关系;并且把该地的轨迹与地面观测和附近气象站的探空观测历史风向玫瑰图作了对比。揭示了该站气流轨迹的季节分布特征,天气系统的位置和移动路径以及大地形对轨迹的影响。结合该站周边城镇的分布和发展规模以及气团移动的轨迹,分析对阿克达拉大气本底站的可能影响,为建立区域大气本底站提供科学的选址依据;为今后在该站开展进一步的研究提供近地层大气气团移动方向和速度背景参考资料;同时,通过实例把轨迹模式模拟方法予以简介,希望其在气体污染物和沙尘的溯源与追踪研究以及对空气污染敏感设施站址的选择、具有污染排放源设施建设的环境评价中得到应用。     

海平面上升对中国沿海地区极值水位重现期的影响

基于中国沿海10个验潮站资料,利用皮尔森Ⅲ型(P-Ⅲ)模型探讨了典型浓度路径(Representative Concentration Pathway,RCP)情景下21世纪海平面上升对中国沿海地区极值水位重现期的影响。结果表明:海平面上升将显著缩短极值水位的重现期。在RCP8.5情景下极值水位的重现期缩短最为显著。预估到2050年,在RCP8.5情景下,所研究的中国沿海地区潮位站的百年一遇极值水位将变为9~43 a一遇。到2100年,在RCP8.5情景下,百年一遇极值水位变为1~18 a一遇。当前极值水位的低概率事件将在2100年变得普遍,在RCP8.5情景下,到2100年千年一遇的几乎每两百年发生一次。由于极值水位的重现期会随着气候变化而缩短,未来沿海地区将会面临更严峻的风险与挑战。     

高压引水隧洞衬砌的透水设计研究

国内大都采用荷载结构法及限裂设计的方法对水工高压隧洞的衬砌进行不透水设计。而实践证明,不透水设计并不适合于高压引水隧洞,它将导致过高的配筋量。目前,国内水工高压隧洞结构透水设计尚无适用的规范可循,因此,有必要寻求一种合理、安全的透水设计方法。针对水工高压隧洞,基于体力理论,提出一种对衬砌结构进行透水设计的有限元计算方法,并将其应用于某水电站工程。该方法可模拟隧洞的施工过程和运营检修工况,考虑渗流场和应力场的直接耦合作用,根据内力值计算衬砌裂缝的开展宽度以及相应的配筋量等。通过对比分析,说明在衬砌透水设计中隧洞满水状态为对其进行配筋的控制工况,且结果更符合工程实际,并能大大节省配筋量。     

中国耕地利用集约度结构变化及其区域差异

Based on the data from the Cost-benefit Data of Farm Produce and the China Agricultural Yearbook, this paper divided the intensity of cultivated land use into labor intensity and capital intensity, and then analyzed their temporal and spatial change at both national and provincial levels between 1980 and 2006. The results showed that: (1) At the national level, labor intensity on food produce decreased from 398.5 day/ha in 1980 to 130.25 day/ha in 2006; and a continuous decrease with a steep decline between 1980 and 1986, a slower decline from 1987 to 1996, and another steep decline from 1997 to 2006. On the contrary, capital intensity shows an increasing trend since 1980. As to the internal composition of capital intensity, the proportion of seed, chemical fertilizer and pesticide input decreased from 90.36% to 73.44% and the proportion of machinery increased from 9.64% to 26.56%. The less emphasis on yield-increasing input and more emphasis on labor-saving input are the main reasons for a slow increase of yield per unit area after 1996. (2) At the provincial level, the developed areas have lower labor intensity and higher capital intensity. The less developed ones have higher labor intensity but lower capital intensity. From the viewpoint of the internal composition of capital intensity, labor-saving input accounts for more proportion in the developed areas than that of other areas. The main reason is that in these developed areas, labor input has become a constraint factor in food production as more and more labors engaged in off-farm work. Farmers increase the labor-saving input for higher labor productivity. However, in the less developed areas, the major constraint is the shortage of capital; food production is still depending on labor and yield-increasing inputs.     

Structural change of agricultural land use intensity and its regional disparity in China

Based on the data from the Cost-benefit Data of Farm Produce and the China Agricultural Yearbook, this paper divided the intensity of cultivated land use into labor intensity and capital intensity, and then analyzed their temporal and spatial change at both national and provincial levels between 1980 and 2006. The results showed that: (1) At the national level, labor intensity on food produce decreased from 398.5 day/ha in 1980 to 130.25 day/ha in 2006; and a continuous decrease with a steep decline between 1980 and 1986, a slower decline from 1987 to 1996, and another steep decline from 1997 to 2006. On the contrary, capital intensity shows an increasing trend since 1980. As to the internal composition of capital intensity, the proportion of seed, chemical fertilizer and pesticide input decreased from 90.36% to 73.44% and the proportion of machinery increased from 9.64% to 26.56%. The less emphasis on yield-increasing input and more emphasis on labor-saving input are the main reasons for a slow increase of yield per unit area after 1996. (2) At the provincial level, the developed areas have lower labor intensity and higher capital intensity. The less developed ones have higher labor intensity but lower capital intensity. From the viewpoint of the internal composition of capital intensity, labor-saving input accounts for more proportion in the developed areas than that of other areas. The main reason is that in these developed areas, labor input has become a constraint factor in food production as more and more labors engaged in off-farm work. Farmers increase the labor-saving input for higher labor productivity. However, in the less developed areas, the major constraint is the shortage of capital; food production is still depending on labor and yield-increasing inputs.     

汶川余震序列的加卸载响应比分析

该文首先将汶川余震序列分成西南、 东北两段, 用加卸载响应比方法分别进行分析, 结果表明震后两段的响应比值都比较低, 明显小于1, 这可判断汶川地震属于主余震型地震; 且地震序列中的强余震(M≥5.0)发生前加卸载响应比值出现明显异常, 大都是加卸载响应比出现峰值, 之后发生强余震。 考虑到主震后余震的时空丛集现象, 结合ETAS模型对原有的加卸载响应比计算式进行改造, 并分析了主震之后15天的改造后响应比值, 发现改造后的响应比在一定程度上消除了丛集的影响, 并展示了对紧随主震发生的强余震的预测能力。