高铁开通前后站区产业空间格局变动及驱动机制——以沪宁城际南京站为例

基于企业微观数据,定量刻画高铁开通前后站区产业空间格局变动,并诊断和确定在不同阶段的关键驱动要素及其贡献度。结果表明,高铁站区产业空间具有明显的圈层结构,但“以高铁站点为中心的向心集聚”在高铁开通初始阶段尚不明显,开发强度并不随着与站点距离增加而降低,核心区的开发强度小于影响区。除了圈层空间分异之外,产业分层集聚态势凸显,与高铁乘客的商务特征相对应的商务服务业在高铁开通后空间集聚程度明显高于其他几类产业;批发零售业、居民服务业和科技服务业与高铁开通相关性不明显;交通运输业和住宿餐饮业作为交通站区的基础服务产业,相关程度介于以上两类之间。从内外两方面驱动因素构建的高铁站区产业空间格局变动模型分析得出,除了交通条件、外部规模经济等传统区位因素外,产业属性、地价对高铁站区产业空间格局的变动有较大影响。     

吉林省松花江流域产业系统环境适应性时空分异与影响因素

基于敏感性,稳定性和响应等适应性要素构建了产业系统环境适应性评价指标体系以及评价模型,并对吉林省松花江流域产业系统环境适应性演变特征以及影响因素进行分析.结果发现:① 产业系统的发展深受内外因素双重扰动作用,重型化的产业发展现实导致了产业系统运行状况不佳,而工业化的大力发展对环境的干扰不断增强;② 不同的适应性要素以及适应性子系统均表现出迥然各异的区域性演变特征,产业系统与环境系统以及产业系统适应力与环境系统适应力均具有非线性变化关系特征.环境系统适应力的提升对于产业系统环境适应性的优化改善均具有更为重要作用;③ 产业系统环境适应性总体表现出由流域自上而下依次降低到中心--外围特征逐渐形成的过程,说明了流域产业系统环境适应性并非一定完全呈现流域的特征,流域内中心性城市功能的发挥也可以影响并且改变其演化发展趋势;④ 产业结构,科学技术,经济发展水平以及政府调控能力是流域产业系统环境适应性的影响因素.     

徐州都市圈工业结构转型及其影响效应分析

在GIS空间分析技术支持下,采用工业结构转型相关指数方法,深入分析了2000~2012年徐州都市圈工业结构转型的时空演化特征及其对区域发展的影响效应。发现：近10 a来徐州都市圈工业转型速度、高级化呈较快提升趋势,且与工业经济增长明显相关,但合理化程度下降;竞争优势行业和主导产业均呈向资本技术密集型行业演化趋势,但主导产业的支撑作用有待增强;空间上呈现先集聚后扩散趋势,不同行业空间集聚程度各异,形成了沿东陇海工业集聚发展轴;工业专业化分工呈现以徐州为核心向外技术水平下降的圈层式垂直分工格局;工业高级化和区域工业占有率对经济增长促进作用显著,而对能源消耗和工业SO₂排放抑制作用明显,但不同尺度区域影响存在差异。     

Development of Productivity Models for the Northern Gulf of Mexico Based on Oxygen Concentrations and Stable Isotopes

Oxygen concentrations have been used for decades to estimate primary production (P) and respiration (R) in aquatic ecosystems. Yet, this approach cannot separate the effects of biological and physical processes affecting oxygen dynamics; therefore, it is now often complemented with the analysis of stable oxygen isotopes. Existing algorithms for calculating primary production and P/R have been developed for closed systems and steady-state open systems. None of these formulations are applicable to productive aquatic ecosystems where diurnal changes in oxygen concentrations and isotope values are usually large. Here, we describe a novel P/R model that includes algorithms for air–sea gas exchange and is not constrained by steady-state conditions. Our objective was to test model sensitivity to variations in input parameters for values commonly observed in coastal waters of the northern Gulf of Mexico. The model was highly sensitive to variations in fractionation factor for respiration (ε) but less sensitive to variations in wind speed, oxygen isotope values of source-water, or oxygen flux through the picnocline. This model is easily transferable to other coastal ecosystems, with a caveat that system-specific values for ε are needed to obtain realistic estimates of P/R.     

Spatial-temporal heterogeneity of industrial structure transformation and carbon emission effect in Xuzhou Metropolitan Area

Employing decoupling index and industrial structure characteristic bias index methods, this study analyzed the spatial-temporal characteristics of industrial structure transformations and their resulting carbon emissions in the Xuzhou Metropolitan Area from 2000 to 2014, with a focus on their relationships and driving factors. Our research indicates that carbon emission intensity from industrial structures in the Xuzhou Metropolitan Area at first showed an increasing trend, which then decreased. Furthermore, the relationship between emissions and industrial economic growth has been trending toward absolute decoupling. From the perspective of the center-periphery, the Xuzhou Metropolitan Area formed a concentric pattern, where both progress towards low emissions and the level of technological advancement gradually diminished from the center to the periphery. In terms of variation across provinces, the ISCB index in the eastern Henan has decreased the slowest, followed by the southern Shandong and the northern Anhui, with the northern Jiangsu ranking last. During this period, resource- and labor- intensive industries were the primary growth industries in the northern Anhui and the eastern Henan, while labor-intensive industries dominated the southern Shandong and capital-intensive industries dominated the northern Jiangsu. In terms of city types, the spatial pattern for industrial structure indicates that recession resource-based cities had higher carbon emission intensities than mature resource-based cities, followed by non-resource-based cities and regenerative resource-based cities. Generally, the industrial structure in the Xuzhou Metropolitan Area has transformed from being resource-intensive to capital-intensive, and has been trending toward technology-intensive as resource availability has been exploited to exhaustion and then been regenerated. Industrial structure has been the leading factor causing heterogeneity of carbon emission intensities between metropolitan cities. Therefore, the key to optimizing the industrial structure and layout of metropolitan areas is to promote industrial structure transformation and improve the system controlling collaborative industrial development between cities.     

The grazing effects of grass shrimp,Palaemonetes pugio, on epiphytic microalgae associated withSpartina alterniflora

Experiments were performed seasonally to estimate grass shrimp,Palaemonetes pugio, grazing on the epiphytic microalgae of cordgrass,Spartina alterniflora, and to determine if grass shrimp have the potential to regulate epiphyte abundance. Grass shrimp were given access to live culms with low and high epiphytic abundance and standing dead culms collected from the streamside levee of a Louisiana salt marsh. Plexiglas frames were used to hold culms upright in aquaria and to restrict grass shrimp access to one half of each culm. We compared epiphyte biomass on the sides of culms exposed to shrimp with the corresponding unexposed sides. Epiphytes were removed from the lowest 10 cm of culms on days 0, 3, and 10, and chlorophylla (chla) measurements on each culm half were made by fluorometry. Chla biomass on culm halves not exposed to grass shrimp significantly increased over time. Percent reductions in chla on culm halves exposed to grass shrimp (calculated by subtraction from the corresponding half not exposed to shrimp) significantly increased over time for at least one culm type in all seasons. Grass shrimp caused an average 30% reduction of epiphyte biomass over 3 d and a 40% reduction over 10 d, suggesting that grass shrimp have the capability of consuming a substantial proportion of the daily production of epiphytes. Epiphytes from standing-dead culms may be more important than those from live culms at the marsh edge to the diet of grass shrimp because chla biomass was, on average, high, and standing-dead culms were seasonally abundant. Diagnostic photosynthetic pigments from selected culms, grass shrimp gut contents, and fecal pellets were identified by high performance liquid chromatography and were used to quantify the taxonomic groups of epiphytic microalgae. Results suggested that diatoms, brown algae, green algae, red algae, and cyanobacteria were present on all culms. Similarities in the pigment content of grass shrimp gut contents and fecal pellets suggested that all algal groups were ingested. Pigment data analysis could not detect a change in the composition of the microalgal assemblage associated with grass shrimp grazing. Assuming that the reduction in chla was due exclusively to grazing, grass shrimp consumed an average of 0.5–1.5 g epiphyte carbon shrimp^?1 d^?1, suggesting that grass shrimp benefit significantly from the consumption ofS. alterniflora epiphytic algae.     

江苏省工业转型的时空分异特征与机理

采用GIS空间分析技术及工业转型系数、工业高级化指数、空间基尼系数、专业化指数和偏离—份额分析等方法,深入分析了2000-2012年江苏省工业转型的时空演化特征及驱动机理.研究发现:近10年来江苏省工业转型速度呈先快后慢而高级化呈较快提升趋势,工业转型对工业发展的促进作用具有滞后性;各工业部门增长速度差异显著,竞争优势行业和主导产业均发生更替,但主导产业的主导作用变化不明显;空间上,不同发展水平的地区工业转型速度、方向及空间集聚程度各异,形成了苏州—无锡、南京、徐州三个工业空间集聚高地;工业专业化分工梯度差异显著,呈现以苏南为核心向外工业技术层次逐渐降低的圈层式垂直分工格局;资源禀赋、技术创新、贸易需求、区域政策是造成江苏工业转型时空分异格局演化的主要驱动力.     

Long-range dependence in the runoff time series of the most important Patagonian river draining to the Pacific Ocean

The Baker River is the largest free-flowing river in Chilean Patagonia. Long-range dependence (LRD), a recognised hydrological property of river runoff worldwide, was detected for the Baker River runoff time series. Analyses were conducted on a monthly scale between 1961 and 2015 using the fractal and multifractal detrended fluctuation analysis methodology. A long-range-dependent Hurst coefficient (H) equal to 0.94 was obtained. A scaling range, which is the signature of LRD, was detected for the Baker River runoff time series between 1 and 5.25 years. Baker River runoff showed a strong correlation (r?=?0.96) with the Antarctic Oscillation (AAO) Index during the 2007–2015 period. The high storage capacity of Lake General Carrera, the size of the Baker River basin area and the dynamics of AAO are proposed as main factors that contribute to the emergence of LRD in the Baker River runoff time series.     

三维叠前深度偏移处理技术应用

近年来,三维叠前深度偏移地震资料处理技术得到了一定的发展,但是由于三维叠前深度偏移处理计算量大,要求有精确的深度-层速度模型,一直未走向工业化生产阶段.本文是在具备大型计算机的基础上,着重对如何求取精确的深度-层速度模型进行了探讨,提出了三维层速度相干反演和三维深度-层速度模型的优化处理方法.     

黄河流域生态经济走廊绿色发展时空分异特征与影响因素识别

基于绿色发展科学内涵,综合构建了黄河流域绿色发展的评价指标体系,并采用熵值法、空间自相关分析、地理探测器模型等多种计量方法研究了 2005-2017年黄河流域生态经济走廊绿色发展时空分异特征与驱动因素,结果如下:①黄河流域绿色发展主要来源于规模化扩张与总量增长的外部驱动作用,热衷于发展速度与规模,忽视质量与效率的内涵式...