上海市三甲医院对周边地区住房价格的空间影响效应分析

选取上海市区7家三级甲等综合性医院,运用特征价格模型和多元回归分析方法,实证分析它们对周边住宅价格的空间影响效应。研究结果显示：① 总体上,相比其他环境区位因素,三甲医院对周边住宅价格的影响程度较小,而建筑面积、物业管理费、学区房、轨道交通、建筑楼高、至 CBD 的距离等因素的影响程度较大。② 三甲综合医院对周边住宅价格产生负面影响。在相同情况下,住宅离医院距离越近,则价格越低。住宅与医院的距离每缩短50 m,住宅价格平均下浮0.602%。③ 由于三甲综合医院区位各不相同,距离CBD远近不一,对住宅价格的影响也存在空间差异。一般来说,距离CBD越近,住宅价格受医院的负面影响也越小。     

黑河下游绿洲植被优势种生物量空间分布及蒸腾耗水估算

基于典型样点试验,建立了研究区植被优势种柽柳、胡杨与苦豆子地上生物量与其生态参数关系模型;利用高分辨率遥感影像Geoeye-1对植被优势种进行分类得到生态参数,实现了其地上部分生物量空间分布估算;最后利用生物量与蒸腾系数关系,估算植被优势种蒸腾耗水。结果显示：植被优势种总生物量为2.53×10⁶t,河流距离对生物量影响显著。根据试验测得的植被优势种蒸腾系数估算出总蒸腾耗水量为10.89×10⁸t,柽柳、胡杨与苦豆子所占比例分别为12.94%,82.93%与4.13%。     

甘肃省能源消费碳足迹变化及影响因素分析(英文)

能源消费是人类活动影响全球气候变化的主要行为之一,对能源消费导致的碳足迹进行研究具有重要意义。本文首先应用能源消费碳足迹的相关概念和方法,计算得到了甘肃省1990年-2009年的总碳足迹、各能源消费类型的碳足迹、碳足迹产值和碳足迹生态压力;然后利用STIRPAT模型进行岭回归函数拟合,探讨了经济增长与碳足迹之间的定量关系,并验证了环境库兹涅茨曲线的存在性;最后通过脱钩指数分析进一步研究了经济增长与碳足迹之间的动态变化关系。结果表明:碳足迹从1990年的每人0.091 ha上升为2009年的每人0.191 ha,呈现波动上升的趋势。各能源消费类型的碳足迹构成中,煤和石油占据了绝对地位,其中又以煤所占比重最大,石油次之,天然气所起的作用甚微。碳足迹产值由1990年的1.18万元ha-1增加为2009年的2.51万元ha-1,碳足迹生态压力也从1990年的0.10上升至2009年的0.24。人口和人均GDP是驱动碳足迹增长的主要因素,且回归分析和脱钩指数分析都表明经济增长与碳足迹之间存在环境库兹涅茨曲线。     

基于结构分解法的北京能源碳排放增量分析(英文)

确保减碳的首要任务是定量测度化石能源消费碳排放的增量影响因素及其大小。为分析北京市1997-2007年的碳排放增量,本文构建了一个扩展的(调入、进口)竞争型经济—能源—碳排放投入产出模型,从整体特征、不同产业、工业行业3个方面,对1997-2007年北京能源消费的碳排放增量进行了结构分解。分析发现:经济规模增长要素(消费、投资、调出和出口等)是拉动碳排放增长的主导因素,能源强度变动效应却是碳减排的决定性因素;在规模扩张因素中,消费和调出超过投资和出口,是碳排放增长的主要贡献者;2002以来新一轮"高碳"特征的工业化导致CO2排量呈急增之势;产业结构调整、三产比重最大使得服务业成为碳排放增长的最大部门,但工业排放的增长却后来居上;碳增排的重点行业是高能耗业,而碳减排的却是能源工业;两时段各效应在不同产业、不同工业行业的影响方向和大小不一。     

中国2000年水足迹的初步计算分析

水足迹是指在一定的物质生活水平下,维持一定人群消费所需要的总的水资源数量.由于考虑了社会经济系统中虚拟水的消费量,水足迹真实地反映了一个地区人类消费对水资源的占有情况,为水资源科学管理提供了非常有用的信息.引入水足迹的概念和计算方法,分析了中国各省2000年人均水足迹.结果表明,西北部省份水足迹较大,南部和中东部省份水足迹较小,青海省水足迹最大,其值为935.75 m3·(人·a)-1,广西水足迹最小,其值为466.31 m3·(人·a)-1.全国平均水足迹为601 m3·(人·a)-1.分析了几个典型省份水足迹的构成,并探讨了降低水足迹以缓解水资源压力的几条途径.     

上海市居民居住迁移的区位选择及其影响因素研究

随着中国住房改革的推进,城市居民通过居住迁移进行住房调整的行为日趋频繁。居住迁移作为城市空间分异和重构的微观机制在城市地理学、住房研究中得到了广泛关注,然而现有研究主要考察居住迁移的发生概率和驱动因素,较少论及居住迁移中的区位选择。论文基于2018年“上海市居民住房和生活空间调查”问卷,采用生命历程和时间地理学视角,刻画居民居住迁移的时空轨迹,并使用多项逻辑斯蒂回归模型探究居住迁移前后居住区位变化的影响因素。研究发现,上海市居民居住迁移的主要区位选择为跨环线向外迁移,但不同世代、不同户口、不同住房产权的居民的居住区位选择有较大差异。生命历程中的年龄、可达性中的工作单位区位以及住房属性中的产权性质都是影响居住迁移区位选择的重要因素。     

Effect of reproductive state and sex on movement and food consumption of western rock lobster (Panulirus cygnus) in a tank environment

The catchability of western rock lobsters (Panulirus cygnus) during the spawning season (October and November) may be affected by their reproductive state. In this study, movement and food consumption of males and females of different reproductive states held in laboratory tanks were measured as proxies for catchability. Density of lobsters was found to influence both movement and food consumption. Solitary animals and, to a lesser extent, two lobsters per tank, were more sedentary and consumed significantly less food than animals at a density of three or four specimens per tank. Tests using three animals per tank confirmed that mature, unmated, and ovigerous females carrying early stage eggs moved more frequently away from their shelters than males or females carrying late stage eggs (P < 0.0001, d.f. = 3). Further, unmated females and females with early stage eggs recorded significantly higher food consumption (P < 0.0061, d.f. = 3) compared with males or females carrying late stage eggs. The greater time spent away from shelter and also food consumption make unmated females and females with early stage eggs likely to be more catchable than males or females with late stage eggs. As catchability is commonly used to obtain population estimates from survey data, these results have implications for surveys which use catch rates of breeding animals as indicators of egg production.     

Is there a link between deep‐sea biodiversity and ecosystem function?

Studying the diversity‐ecosystem function relationship in the deep sea is of primary importance in the face of biodiversity loss and for our understanding of how the deep sea functions. Results from the first study of diversity‐ecosystem function relationships in the deep sea (Danovaro et al. 2008; Current Biology, 18, 1–8) are unexpected and show an exponential relationship between deep‐sea nematode diversity and ecosystem function and efficiency, although this relationship appears largely restricted to relatively low diversities [ES(51) <25]. Here, we investigate the relationship between nematode diversity and several independent measures/proxies of ecosystem function (sediment community oxygen consumption, bacterial biomass, bacterial extracellular enzyme activity) and efficiency (ratio of bacterial/nematode carbon to organic C content of the sediment) on the New Zealand continental slope. Nematode diversity at our study sites was relatively high [ES(51) = 30–42], and there was no relationship between species/functional diversity and ecosystem function/efficiency after accounting for the effects of water depth and food availability. Our results are consistent with a breakdown of the exponential diversity‐function relationship at high levels of diversity, which may be due to increased competition or greater functional redundancy. Future studies need to take into account as many environmental factors and as wide a range of diversities as possible to provide further insights into the diversity‐ecosystem function relationship in the largest ecosystem on Earth.     

盐度对近江牡蛎耗氧率、排氨率、O:N 和吸收率的影响

以半现场流水槽法研究了不同盐度(5、10、15、20、25、30、35)对近江牡蛎(Crassostrea hongkongensis)耗氧率、排氨率、O:N、吸收率的影响,并测定了盐度为20条件下牡蛎耗氧率和排氨率的周日变化.结果表明,近江牡蛎耗氧率、排氨率、O:N先随着盐度的升高而下降,在20左右降到最低,随着盐度继续上升,又升高;而近江牡蛎的吸收率先随着盐度的升高而升高,在20左右达到最高,然后随盐度升高而下降.根据数据得出耗氧率与盐度的拟合方程: y=0.0033x2-0.1161x+1.5523, R2=0.9018;排氨率与盐度:y=0.0001x2-0.0041x+0.0871, R2=0.9889;O:N与盐度:y=0.0016x3-0.0782x2+0.9051x+10.818, R2=0.955;吸收率与盐度: y=-0.0011x2+0.0399x+0.4393.R2=0.9453.一日内,8时、14时、19时、22时4个时间点,近江牡蛎耗氧率和排氨率变化较大,在14时最大,表明该时点其代谢活动最强.     

Residents′Activity-travel Behavior Variation by Communities in Beijing,China

China’s transition from a planned economy to a market economy has resulted in many changes in its urban structure and society and provided an opportunity for a quasi-longitudinal case study on the relationship between the built environment and activity-travel behavior.This paper draws upon data from an activity diary survey conducted in Beijing in 2007.The survey sample comprised 652 residents living in Danwei(work unit),commodity housing,and affordable housing neighborhoods.On the basis of the three-dimensional geo-visualization analysis of the space-time path and statistical multivariate regression models of daily travel and leisure time,it was found that both residential spatial factors and socio-demographics influence residents’ daily behaviors.The findings show that Danwei residents have less daily travel time than those who live in commodity housing,but people living in affordable housing endure the longest travel time.Daily leisure time is associated more with individual attributes.We argue that although China’s transition is currently gradual,the Danwei system may continue to play significant roles in daily life,and it might provide a valuable model for neighborhood spatial planning.