A proposal for the theoretical analysis of the interactive coupled effects between urbanization and the eco-environment in mega-urban agglomerations

Mega-urban agglomerations are strategic core areas for national economic development and the main regions of new urbanization. They also have important roles in shifting the global economic center of gravity to China. However, the development of mega-urban agglomerations has triggered the interactive coercion between resources and the eco-environment. The interactive coupled effects between urbanization and the eco-environment in mega-urban agglomerations represent frontier and high-priority research topics in the field of Earth system science over the next decade. In this paper, we carried out systematic theoretical analysis of the interactive coupling mechanisms and coercing effects between urbanization and the eco-environment in mega-urban agglomerations. In detail, we analyzed the nonlinear-coupled relationships and the coupling characteristics between natural and human elements in mega-urban agglomerations. We also investigated the interactive coercion intensities between internal and external elements, and the mechanisms and patterns of local couplings and telecouplings in mega-urban agglomeration systems, which are affected by key internal and external control elements. In addition, we proposed the interactive coupling theory on urbanization and the eco-environment in mega-urban agglomerations. Furthermore, we established a spatiotemporal dynamic coupling model with multi-element, multi-scale, multi-scenario, multi-module and multi-agent integrations, which can be used to develop an intelligent decision support system for sustainable development of mega-urban agglomerations. In general, our research may provide theoretical guidance and method support to solve problems related to mega-urban agglomerations and maintain their sustainable development.     

Solar-, monsoon- and Kuroshio-influenced thermocline depth and sea surface salinity in the southern Okinawa Trough during the past 17,300 years

Factors influencing millennial-scale variability in the thermocline depth (vertical mixing) and sea surface salinity (SSS) of the southern Okinawa Trough (OT) during the past 17,300 years were investigated based on foraminifer oxygen isotope records of the surface dweller Globigerinoides ruber sensu stricto and the thermocline dweller Pulleniatina obliquiloculata in the AMS ¹⁴C dated OKT-3 core. The thermocline depth is influenced by surface thermal buoyancy (heat) flux, in turn controlled by the annual mean insolation at 30°N and the strength of the East Asian winter monsoon (EAWM). Strong insolation and weak EAWM tend to increase buoyancy gain (decrease buoyancy loss), corresponding to shallow thermocline depths, and vice versa. Regional SSS is influenced by the global ice volume, the Kuroshio Current (KC), and vertical mixing. A deep thermocline coincides with a high SSS because strong vertical mixing brings more, saltier subsurface KC water to the surface, and vice versa. Local SSS (excluding the global ice volume effect) became lower in the northern OT than in the southern OT after ~9.2 ka, implying that Changjiang diluted water had stronger influence in the northern sector. SSS show no major changes during the Bølling/Allerød and Younger Dryas events, probably because the KC disturbed the North Atlantic signals. This argues against earlier interpretations of sea surface temperature records of this core. Wavelet and spectral analyses of the Δδ¹⁸O_P-G (δ¹⁸O of P. obliquiloculata minus G. ruber s.s.) and δ¹⁸O_local records display 1,540-, 1,480-, 1,050-, 860-, 640-, and 630-year periods. These are consistent with published evidence of a pervasive periodicity of 1,500 years in global climate as well as EAWM and KC signatures, and a fundamental solar periodicity of 1,000 years and intermediary derived periodicity of 700 years.     

2008年春季中国南方冰雪冻害林木折损分析

An abrupt ice and snow storm disaster which occurred in the spring of 2008 se-verely destroyed forests over a surprisingly large portion of southern China.A transect crossing Jinggang Mountain-Jitai Basin-Yushan Mountain-Wuyi Mountain was selected as the study area.The authors integrated field data collected in two field surveys to analyze the impacts of the disturbance on forests.The following results were obtained.(1) The extent of damage to plantations along the transect decreased in the order of slash pine > masson pine > mixed plantation > Chinese fir.Slash pine is an introduced species from southern America which is characterized by fast growth,low wood quality and rich oleoresin,and showed a damage rate of 61.3% of samples,of which 70.4% cannot recover naturally.Masson pine is the native pioneer species of forests with harder wood,and 52.5% were damaged due to turpentine,of which 60.9% cannot recovery naturally.Chinese fir is a local tree species and samples showed a rate of 46% and a relative rate of 32.5%,lower than the mixed plantation.(2) From west to east along the transect,we can see that evergreen broad-leaved forest of the western transect on Jinggang Mountain showed the lightest damage extent,and a Cryp-tomeria plantation at an altitude of 700 m was severely destroyed while Chinese fir showed light damage below 700 m and relatively severe damage above 900 m.Masson pine and slash pine in the central transect in Jitai Basin were damaged severely due to turpentine ac-tivities,and closed natural secondary deciduous broad-leaved forest was damaged severely due to high ice and snow accumulation on intertwined shrubs.Masson pine aerial-seeding plantations below 400 m along the eastern transect in Xingguo and Ningdu counties were nearly undamaged for small tree sizes,and Chinese fir at 500-900 m altitude showed a lighter damage extent.However,masson pine which was distributed above 400 m and planted in the 1960s,was severely damaged due to turpentine.     

农村居民点动态演变及驱动机制研究——以江苏省宜兴市为例

选取宜兴市为研究区,在GIS和RS技术的支撑下,对农村居民点用地的规模变化和空间分布进行分析,对引起农村居民点用地变化的驱动因素进行研究。结果表明:1农村居民点用地整体呈下降趋势,变化速度逐年减慢,主要新增来源是农用地,主要转移去向是城镇建设用地;2在地形平坦、距离水源和农用地较近的地区,农村居民点分布密集;3经济发展、人口减少、交通改善和城市化水平提高是影响农村居民点变化的主要驱动因素。     

Modified multispectral space for color representation

IntroductionIn color reproduction and communication, met-amer exists inherently when the conventionalcondition matching used. Therefore , the colordifference introduced makes the accuracy of colorrepresentation be lowered.In order to eli minatemetamer CIE developed the scheme so-calledspectra matching in Publication 15 .2 and speci-fied that using band-pass filters with 5 nminter-val to sample and then reconstruct the originalcolor signal ,thus the color difference will disap-pear[1].Spectra…     

A New Solar Radio Spectrometer at 1.10-2.06 GHz and First Observational Results

An improved Solar Radio Spectrometer working at 1.10-2.06 GHz with much improved spectral and temporal resolution, has been accomplished by the National Astronomical Observatories and Hebei Semiconductor Research Institute, based on an old spectrometer at 1-2 GHz. The new spectrometer has a spectral resolution of 4 MHz and a temporal resolution of 5ms, with an instantaneous detectable range from 0.02 to 10 times of the quiet Sun flux. It can measure both left and right circular polarization with an accuracy of 10% in degree of polarization. Some results of preliminary observations that could not be recorded by the old spectrometer at 1-2 GHz are presented.     

Numerical simulation of Pacific water intrusions into Otsuchi Bay,northeast of Japan,with a nested-grid OGCM

A numerical simulation of Otsuchi Bay located on the northeast coast of the Honshu, the largest island of Japan, is conducted, using an ocean general circulation model (OGCM) with a nested-grid system in order to illustrate seasonal variability of the circulation in the bay. Through a year, an anticlockwise circulation is dominant in the bay, as observational studies have implied, although it is modified in the bay-mouth-half of the bay in winter. In addition, there is an intense outflow at the surface layer during spring to autumn, influenced by river water discharge. Intrusion of the Pacific water into the bay is influened by mean circulations, but it is also influenced by baroclinic tides from spring to autumn. Pacific water intrusions affected by baroclinic tides may have an impact on the environment in Otsuchi Bay.     

哈大巨型城市带空间开发-经济发展-环境演变的耦合分异机制

通过构建空间开发、经济发展、资源环境水平的评价指标体系,引入耦合度概念,并应用变异系数、趋势面分析、回归分析等定量模型研究2000~2014年哈大巨型城市带空间开发-经济发展-环境演变的耦合分异特征及其影响机制,主要得到以下结论：① 2000年以来哈大巨型城市带各城市空间开发-经济发展-环境演变的耦合度均处在不同程度失调状态,且整体表现为“西高东低-南高北低”的空间格局,但耦合度水平总体趋于上升。哈长次区域和辽中南次区域以及哈大巨型城市带整体的耦合度波动性均先升高后下降,总体趋势不断向好;② 政府投入强度是2000年影响哈大巨型城市带各城市耦合度差异的重要作用因素,资本投入强度与科技投入规模是2007年、2014年2个阶段的主导影响因素,且城市发展能级差异与2007年各城市间的耦合度差异表现出一致性;③ 在政府投入强度、科技投入规模、资本投入强度等因素的共同作用下,哈长次区域空间开发-经济发展-环境演变的耦合程度出现空间分异。辽中南次区域耦合度分异的影响因素由人力资本效率和行政等级逐渐演变为以资本投入强度主导。     

Respiration and Calcification of <Emphasis Type="Italic">Crassostrea gigas</Emphasis>: Contribution of an Intertidal Invasive Species to Coastal Ecosystem CO<Subscript>2</Subscript> Fluxes

Respiration and calcification rates of the Pacific oyster Crassostrea gigas were measured in a laboratory experiment in the air and underwater, accounting for seasonal variations and individual size, to estimate the effects of this exotic species on annual carbon budgets in the Bay of Brest, France. Respiration and calcification rates changed significantly with season and size. Mean underwater respiration rates, deducted from changes in dissolved inorganic carbon (DIC), were 11.4 μmol DIC g⁻¹ ash-free dry weight (AFDW) h⁻¹ (standard deviation (SD), 4.6) and 32.3 μmol DIC g⁻¹ AFDW h⁻¹ (SD 4.1) for adults (80–110 mm shell length) and juveniles (30–60 mm), respectively. The mean daily contribution of C. gigas underwater respiration (with 14 h per day of immersion on average) to DIC averaged over the Bay of Brest population was 7.0 mmol DIC m⁻² day⁻¹ (SD 8.1). Mean aerial CO₂ respiration rate, estimated using an infrared gas analyzer, was 0.7 μmol CO₂ g⁻¹ AFDW h⁻¹ (SD 0.1) for adults and 1.1 μmol CO₂ g⁻¹ AFDW h⁻¹ (SD 0.2) for juveniles, corresponding to a mean daily contribution of 0.4 mmol CO₂ m⁻² day⁻¹ (SD 0.50) averaged over the Bay of Brest population (with 10 h per day of emersion on average). Mean CaCO₃ uptake rates for adults and juveniles were 4.5 μmol CaCO₃ g⁻¹ AFDW h⁻¹ (SD 1.7) and 46.9 μmol CaCO₃ g⁻¹ AFDW h⁻¹ (SD 29.2), respectively. The mean daily contribution of net calcification in the Bay of Brest C. gigas population to CO₂ fluxes during immersion was estimated to be 2.5 mmol CO₂ m⁻² day⁻¹ (SD 2.9). Total carbon release by this C. gigas population was 39 g C m⁻² year⁻¹ and reached 334 g C m⁻² year⁻¹ for densely colonized areas with relative contributions by underwater respiration, net calcification, and aerial respiration of 71%, 25%, and 4%, respectively. These observations emphasize the substantial influence of this invasive species on the carbon cycle, including biogenic carbonate production, in coastal ecosystems.