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区划是地理学认识地理环境地域分异规律和优化人地关系地域系统结构与功能的有效手段。本文首先借鉴已有研究,对区域生态经济学这门新兴交叉学科及生态经济区划等相关概念进行了界定,明确了生态经济区划原则。其次,通过设计两级生态经济区划方案,首次对中蒙俄三国重要的经济增长轴带“中蒙俄经济走廊”这一国际区域进行了生态经济区划探索研究。基于研究区地貌、气候等自然地理要素以及经济开发强度等人文经济要素,首先将研究区划分为6类生态经济区。通过引入人均环境污染物产生量、土地利用类型、产业结构、人均GDP、城镇化率等具体生态环境和经济社会指标,进一步将研究区细化为19类生态经济亚区。最后,综合对比分析各类生态经济亚区的生态环境与经济社会特征及地域分异规律,贯彻绿色可持续发展理念,将其确定为优化发展区、重点发展区和保育发展区3类,并提出了针对不同类型区的绿色发展建议。本研究将为中蒙俄经济走廊的绿色发展提供科学支撑。 相似文献
2.
V. M. Mishin A. D. Bazarzhapov U. Sukhbaatar M. Förster 《Geomagnetism and Aeronomy》2010,50(8):988-996
The simplest theory of electric circuits is applied to analysis of the observed large-scale electric field and currents in
a disturbed magnetosphere-ionosphere system. Maps of distribution of field-aligned currents (FACs) obtained from ground-based
magnetic measurements using the original magnetogram inversion method (MIT) and measurements by satellites were used. A method
for circuit determination according to the data of such maps based on the detection of spatial R.N inhomogeneities in each
of three Iijima and Potemra FAC zones is proposed. The results of the new method are used to describe some electric field
and current generators not known before, new types of current systems in tail lobes and plasma sheet, and the formation and
dynamics of new types of three-dimensional systems with auroral electrojets and meridional ionospheric Pedersen current, which
have not been paid due attention in the literature. 相似文献
3.
V. Mishin Z. Pu L. Sapronova A. Bazarzhapov Yu. Kuz’minykh X. Cao H. Zhang 《Geomagnetism and Aeronomy》2009,49(8):1193-1198
The maps of the field-aligned current (FAC) density distribution in the ionosphere obtained by the TIM-2 magnetogram inversion
technique are used to investigate the August 27, 2001 substorm. The open magnetic flux Ψ and intensity J of the substorm current wedge (SCW) have been determined with a step of 1–5 min. The substorm onsets are divided into two
types, PSR (plasma sheet reconnection) and TLR (tail lobe reconnection). The fast expansion tailward of the PSR region is
described as the transition from PSR to PSR+TLR. Assuming that the SCW FACs flow down into the ionosphere from the edges of
the disruption region of the cross-tail dawn-dusk current, several parameters of the disruption region have been estimated.
The disrupted magnetic field has been found to be ∼5% of the undisrupted one for PSR and ∼95% for PSR+TLR. The disturbance
power Q for PSR is an order of magnitude lower than that for PSR+TLR. The abrupt growth of Q during the transition from PSR to PSR+TLR is observed over the entire SCW area from its near-Earth part to the midtail and
distant tail. 相似文献
4.
Mishin V. M. Saifudinova T. I. Karavaev Yu. A. Kurikalova M. A. Bazarzhapov A. D. 《Geomagnetism and Aeronomy》2009,49(7):975-982
The regular appearance of the chain of oppositely directed field-aligned current (FAC) pairs near the noon-midnight meridian
during three considered substorms has been described. The FAC pairs (FACs flowing into the ionosphere in the morning and flowing
out of this region in the evening and vice versa) are observed in each of three Iijima and Potemra zones. The FAC direction
in the fixed LT sector periodically varies along the chain. The scenario, according to which each FAC pair (seven pairs) is
identified with a hump or trough of one of the waves propagating from the Earth and toward the Earth in different magnetospheric
domains, has been described. The estimated wave velocities differ from ∼100 to >1000 km/s depending on the propagation region
but everywhere agree with the corresponding velocities of magnetosound waves (MSWs). The hypothesis is proposed, according
to which these MSWs are excited by plasma ejection during current disruption and reconnection near the dayside magnetopause
and in the near/middle regions of the nightside tail. 相似文献
5.
Based on statistical data and a detailed analysis of geomagnetic response to the hard electromagnetic radiation of the X17
solar flare of September 7, 2005, we considered spatial features of current systems producing the geomagnetic solar flare
effect (SFE). During flares accompanied by intensive X-rays and gamma rays, SFEs are shown to be observed globally, including
the night hemisphere and high latitudes. Cause-effect relations of phenomena under consideration are discussed. 相似文献
6.
E. A. Ponomarev A. D. Bazarzhapov V. F. Petrukhin I. V. Poddubnaya 《Geomagnetism and Aeronomy》2010,50(7):854-859
The possibility of the occurrence of sporadic layers in the ionospheric dynamo region due to the formation of thin layers
with large plasma pressure gradients balancing the Ampere force is considered. Observational data confirming the validity
of such an approach are presented. 相似文献
7.
V. M. Mishin A. D. Bazarzhapov V. V. Mishin U. Sukhbaatar M. Förster 《Geomagnetism and Aeronomy》2011,51(7):937-945
A model of alignment of the field-aligned current generator system in the disturbed magnetosphere is proposed. It has been
found that Pedersen currents in the disturbed ionosphere of the auroral oval are meridional. They connect oppositely directed
field-aligned currents (FACs) of two adjacent Iijima and Potemra (IP) regions. This supplements the dominant concept of currents
in the literature, in which a substorm current wedge plays a major role. During the considered substorm, graphs have been
obtained of changes in FAC intensities in each of the three Iijima and Potemra regions of the Northern Hemisphere. These new
data suggest that during a disturbance, the Region 1 FAC and the sum of regions 2 and 0 FACs remain equal. The equality means
that these three generators form a unified system. Inequalities of intensities between two FACs of different sign simultaneously
observed in the dawn and dusk sectors have also been detected in each IP region. A conceptual model is proposed for the formation
of this dawn-dusk asymmetry. In the model, in addition to FACs that close up in the ionosphere of the Northern Hemisphere,
FACs connecting the two hemispheres are also presented. The conclusion is justified that the global magnetospheric dynamo
operates as a voltage generator under relatively quiet (average) conditions, as during storms. 相似文献
8.
V. M. Mishin M. Foerster T. I. Saifudinova A. D. Bazarzhapov Yu. A. Karavaev L. A. Sapronova S. I. Solovyev 《Geomagnetism and Aeronomy》2007,47(4):429-441
The interval 0000-1400 UT of the superstorm of November 20, 2003, has been studies based on the ACE/WIND data and the MIT2 magnetogram inversion technique. The distributions of the electric potential and currents, field-aligned currents, and Joule heat in the ionosphere have been calculated. The variable magnetotail length and powers coming into the magnetosphere, ionosphere and ring current have been estimated. The selected superstorm intervals, when it became possible to identify the disturbance mode produced by the interaction between the variable solar wind dynamic pressure and IMF effects, have been described. Spontaneous substorms, two types of driven responses to changes in IMF or in the solar wind dynamic pressure (P d ), zero events at simultaneous jumps of IMF and P d , and a previously unknown mode of saturation of the ionospheric electric field at a redistribution of the energy coming into the magnetosphere between the ionosphere and ring current are among the selected modes. 相似文献
9.
Karavaev Yu. A. Sapronova L. A. Bazarzhapov A. D. Saifudinova T. I. Kuz’minykh Yu. V. 《Geomagnetism and Aeronomy》2009,49(7):961-969
The magnetospheric storm on November 20, 2003 was one of two greatest events in 1957–2003. The D
st* index reached −472 nT, the polar cap potential drop exceeded 200 kV, the polar cap boundary expanded up to Φ = 60°, the plasma
layer density in the synchronous orbit reached 5 cm−3, and the inner edge of the plasma sheet penetrated up to L ∼ 1.5R
E. The sequence of disturbance modes including some previously unknown is described. The distribution of the total power input
into the magnetosphere between the ionosphere (power Q
i) and the ring current (Q
DR), as well as the relative roles of the spontaneous substorms and the driven disturbances in the creation of the DR current, is analyzed. The values of the parameter α = Q
DR/Q
i are calculated with a step of 5 min. It is shown that intervals with α ≪ 1 and with maximums α ≫ 1 were observed in the events
under consideration. These results contradict the dominant opinion that the energy input into the magnetosphere during disturbances
is primarily dissipated in the ionosphere. The two types of α maximums are observed: one in the mode of a prevailing spontaneous
substorm and the other in the mixed mode of the substorm and driven disturbance. It is concluded that both types of the maximums
and corresponding enhancements of the DR current appeared due to the plasma turbulization processes in the substorm current
wedge. The parameter α appears to slowly increase from α ≪ 1 to α > 1 with increasing activity level; this trend supports
the driven model of creating the DR current due to an increase in the electric field of the solar wind. 相似文献
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