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21.
胶州湾菲律宾蛤仔死壳分布与生态环境关系的研究 总被引:1,自引:0,他引:1
胶州湾菲律宾蛤仔栖息地带由于近年受拖耙捕生产,底质遭到频繁骚动。同时沿岸带局部水域环境污染严重,以及河口盐度突发性骤降等因素,直接影响了蛤仔的存活率。因而蛤仔死壳逐年增多。据1990年调查,9月份幼蛤和成蛤死壳平均密度比同年4月分别增加3.5倍和1.8倍,蛤仔资源量亦受一定损失。 相似文献
22.
李柱臣 《中国地理科学(英文版)》1992,2(1):56-63
The Loess Plateau is one of China s developing areas where socio-econ-omy is backward, ecological environment deteriorated and people's life difficult.The purpose of carrying out comprehensive development of the area's agriculture is, in essence, to open up new fields of agro-production, to intensify the utilization of related resources, to raise productivity and to win bigger output. The decision is important, as by so doing, the physical landscape could be tranformed, the local economy could be flourished, and the people's standard of living could be improved, and moreover the national development strategy of "depending on the East and shifting to the West" and building Shanxi Province into an energy and chemical industrial base could be realized.Based on field investigations in recent years, the auther proposed the purpose, target, principles, steps, tactics and strategies for the comprehensive development of the are's agriculture. 相似文献
23.
24.
This paper presents a continuous version of the model of distribution dynamics to analyse the transition dynamics and implied
long-run behaviour of the EU-27 NUTS-2 regions over the period 1995–2003. It departs from previous research in two respects:
first, by introducing kernel estimation and three-dimensional stacked conditional density plots as well as highest density regions
plots for the visualisation of the transition function, based on Hyndman et al. (J Comput Graph Stat 5(4):315–336, 1996), and second, by combining Getis’ spatial filtering view with kernel estimation to explicitly account for the spatial dimension of the
growth process. The results of the analysis indicate a very slow catching-up of the poorest regions with the richer ones,
a process of shifting away of a small group of very rich regions, and highlight the importance of geography in understanding
regional income distribution dynamics.
相似文献
Manfred M. FischerEmail: |
25.
华南海西—印支成矿期内,成矿序列完整,类型齐全,矿种繁多,为其它成矿期所莫及。沉积矿床需要稳定的地质背景,层控矿床形成的较有利的地质背景是稳中有动。 相似文献
26.
地学“开合律”及其在造山带研究中的意义 总被引:14,自引:2,他引:12
“开合律”是地学辩证法基本规律之一。本文概述了它的内容与特点,阐明它在造山带研究中的意义及运用它指导造山带研究的步骤,并根据目前已总结的5种“开”、“合”类型相应地提出了5种造山带类型。 相似文献
27.
根据国内外大量实际资料,从碘的分布情况及其所处的地质条件,结合石油和天然气形成过程、油气藏类型及其分布特点,探讨高碘卤水分布的规律及其形成条件,在此基础上指出了我国的找碘方向。 相似文献
28.
The main result of this work is to show that macroseismic intensity decay with distance strongly depends on the epicentral intensity. An attenuation law that takes this parameter into account is proposed for Metropolitan France, from the analysis of SISFRANCE macroseismic database. Such a model significantly reduces the difference between observed and theoretical intensities. A map of the attenuation variations is also set up for Metropolitan France. No major site effects are observed, but at a broad scale, young Alpine regions display a stronger attenuation than old Hercynian regions. To cite this article: P. Arroucau et al., C. R. Geoscience 338 (2006). 相似文献
29.
The devastating 1999 Marmara and Düzce earthquakes led to a significant increase in the earthquake studies in Turkey in geological,
engineering and financial aspects. Extreme Value Theory (EVT) has a range of applications from stock market changes to natural
disasters like floods and hurricanes. Here EVT is fitted to the ordinary and earthquake reinsurance claims of Turkey. 相似文献
30.
A shakemap system providing rapid estimates of strong ground shaking could be useful for emergency response providers in a
damaging earthquake. A hybrid procedure, which combines site-dependent ground motion prediction models and the limited observations
of the Real-Time Digital stream output system (RTD system operated by Central Weather Bureau, CWB), was set up to provide
a high-resolution shakemap in a near-real-time manner after damaging earthquakes in Taiwan. One of the main factors that affect
the result of ground motion prediction analysis is the existence of site effects. The purpose of this paper is to investigate
the local site effects and their influence in the ground shaking and then establish an early estimation procedure of potential
hazard for damaging earthquakes. Based on the attenuation law, the site effects of each TSMIP station are discussed in terms
of a bias function that is site and intensity-level dependent function. The standard deviation of the site-dependent ground
motion prediction model can be significantly reduced. The nonlinear behavior of ground soil is automatically taken into account
in the intensity-level dependent bias function. Both the PGA and the spectral acceleration are studied in this study. Based
on the RTD data, event correctors are calculated and applied to precisely estimate the shakemap of damaging earthquakes for
emergency response. 相似文献