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排序方式: 共有65条查询结果,搜索用时 31 毫秒
1.
In this paper, we briefly describe the general destruction caused by historic earthquakes in major cities of China, preliminarily analyze the heaviness and widespread occurrence of earthquakes in cities of China, and suggest that research on scenario earthquakes in cities should be developed as a part urban disaster reduction research.  相似文献   
2.
To a set of well-regarded international scenarios (UNEP’s GEO-4), we have added consideration of the demand, supply, and energy implications related to copper production and use over the period 2010–2050. To our knowledge, these are the first comprehensive metal supply and demand scenarios to be developed. We find that copper demand increases by between 275 and 350% by 2050, depending on the scenario. The scenario with the highest prospective demand is not Market First (a “business as usual” vision), but Equitability First, a scenario of transition to a world of more equitable values and institutions. These copper demands exceed projected copper mineral resources by mid-century and thereafter. Energy demand for copper production also demonstrates strong increases, rising to as much as 2.4% of projected 2050 overall global energy demand. We investigate possible policy responses to these results, concluding that improving the efficiency of the copper cycle and encouraging the development of copper-free energy distribution on the demand side, and improving copper recycling rates on the supply side are the most promising of the possible options. Improving energy efficiency in primary copper production would lead to a reduction in the energy demand by 0.5% of projected 2050 overall global energy demand. In addition, encouraging the shift towards renewable technologies is important to minimize the impacts associated with copper production.  相似文献   
3.
In this study, an interval-parameter multi-stage stochastic linear programming (IMSLP) method has been developed for water resources decision making under uncertainty. The IMSLP is a hybrid methodology of inexact optimization and multi-stage stochastic programming. It has three major advantages in comparison to the other optimization techniques. Firstly, it extends upon the existing multi-stage stochastic programming method by allowing uncertainties expressed as probability density functions and discrete intervals to be effectively incorporated within the optimization framework. Secondly, penalties are exercised with recourse against any infeasibility, which permits in-depth analyses of various policy scenarios that are associated with different levels of economic consequences when the promised water-allocation targets are violated. Thirdly, it cannot only handle uncertainties through constructing a set of scenarios that is representative for the universe of possible outcomes, but also reflect dynamic features of the system conditions through transactions at discrete points in time over the planning horizon. The developed IMSLP method is applied to a hypothetical case study of water resources management. The results are helpful for water resources managers in not only making decisions of water allocation but also gaining insight into the tradeoffs between environmental and economic objectives.  相似文献   
4.
An important task of natural resource management is deciding amongst alternative policy options, including how interventions will affect the dynamics of resource exploitation. Yet predicting the behaviour of natural resource users in complex, changeable systems presents a significant challenge for managers. Scenario planning, which involves thinking creatively about how a socio-ecological system might develop under a set of possible futures, was used to explore uncertainties in the future of the Indian Ocean tuna purse seine fishery. This exercise stimulated thinking on how key social, economic and environmental conditions that influence fleet behaviour may change in the future, and how these changes might affect the dynamics of fishing effort. Three storylines were explored: an increase in marine protection, growing consumer preference for sustainable seafood, and depletion of tuna stocks. Comparing across several possible future scenarios, a number of critical aspects of fleet behaviour were identified that should be important considerations for fishery managers, but which are currently poorly understood. These included a switch in fishing practices, reallocation of effort in space, investment in new vessels and exit from the fishery. Recommendations for future management interventions in the Indian Ocean were offered, along with suggestions for research needed to reduce management uncertainty.  相似文献   
5.
 Due to the lack of an effective policy of planning and prevention, over the past decades the area around Mt. Vesuvio has undergone a steady increase in population and uncontrolled housing development. Consequently, it has become one of the most hazardous volcanic areas in the world. In order to mitigate the damage that the impact of an explosive event would cause in the area, the Department of Civil Defense has worked out an Emergency Management Plan using the A.D. 1631 subplinian eruption as the most probable short-term event. However, from 25 000 years B.P. to present, the activity of the Somma-Vesuvio volcano has shown a sequence of eight eruptive cycles, which always began with a strong plinian eruption. In this paper we utilize the A.D. 79 eruption as an example of a potential large explosive eruption that might occur again at Vesuvio. A detailed tephrostratigraphic analysis of the eruption products was processed by a multivariate statistical analysis. This analysis proved useful for identifying marker layers in the sequences, thus allowing the recognition of some major phases of synchronous deposition and hence the definition of the chronological and spatial evolution of the eruption. By combining this reconstruction with land-use maps, a scenario is proposed with time intervals in the eruptive sequence similar to those reported in Pliny's letter. Thus, it was calculated that, after 7 h from the start of the eruption, a total area of approximately 300 km2 would be covered with the eruption products. In the following 11 h, a total area of approximately 500 km2 would be involved. The third and last phase of deposition would not cause significant variation in the total area involved, but it would bring about an increase in the thickness of the pyroclastic deposits in the perivolcanic area. Received: 30 November 1996 / Accepted: 29 May 1997  相似文献   
6.
The Chinese government actively follows the low-carbon development pattern and has set the definite targets of reducing carbon emissions by 2030. The industrial sector plays a significant role in China's economic growth and CO2 emissions. This is the first study to present a specific investigation on the retrospective decomposition (1993–2014) and prospective trajectories (2015–2035) of China's industrial CO2 emission intensity (ICEI) and industrial CO2 emissions (ICE), aiming at China Industrial Green Development Plan 2016–2020 targets and China's 2030 CO2 emission-reduction targets. We introduce process carbon intensity, investment and R&D factors into the decomposition model and make a combination of dynamic Monte Carlo simulation and scenario analysis to identify whether and how the targets would be realized from a sector-specific perspective. The results indicate that investment intensity is the primary driver for the increase in ICEI, while R&D intensity and energy intensity are the leading contributors to the reduction in ICEI. Under existing policies, it is very possible for the industrial sector to achieve the 2020 and 2030 intensity-reduction targets. However, the realization of 2030 emission-peak target has some uncertainties and needs extra efforts in efficiency improvement and structural adjustment. All the five scenarios would achieve the 2020 and 2030 intensity-reduction targets, except Scenario N4 for China Industrial Green Development Plan 2016–2020 target. Nonetheless, only three scenarios would realize the 2030 emission-peak target. With strong efficiency improvement and structural adjustment, ICE would hit the peak in 2025. In contrast, with high/low efficiency improvement and weak structural adjustment, ICE would fail to reach the peak before 2035. Both ICEI and ICE have substantial mitigation potentials with the enhancement of efficiency improvement and structural adjustment. Finally, we suggest that the Chinese government should raise the baseline requirements of efficiency improvement and structural adjustment for the industrial sector to achieve China’s 2030 targets.  相似文献   
7.
This paper explores the seafood sector in Indonesia, using fish supply-demand modeling, with special focus on the growing role of aquaculture in the country's food portfolio. The paper describes six scenarios for future fish supply–demand dynamics and examines the role of aquaculture growth in fish supply in Indonesia. A business as usual scenario (BAU) assumed exogenous variables of our supply-demand model following historical trends. Five alternative scenarios explored the implications of stagnant capture fisheries; export-oriented growth of aquaculture; domestic-oriented aquaculture growth; slow growth of aquaculture sector; and disease outbreaks to key aquaculture species. The BAU scenario projected that fish supply and demand in Indonesia continues to increase over time and strong aquaculture growth is critical to meet increasing demand for fish. Stagnant capture fisheries resulted in increasing fish prices and decreasing fish consumption. Export-oriented aquaculture growth benefitted fish supply and exports, but also helped lower domestic prices and thus increase consumption. An emphasis on domestic aquaculture commodities increased fish supply, providing best domestic consumption outcomes and lower consumer prices. Slow aquaculture growth reduced fish supply and led to undesirable increases in domestic prices and decreasing domestic consumption as a consequence. Disease outbreaks in shrimp and carp aquaculture resulted in a short-term reduction in aquaculture output and increasing fish prices, lowering fish consumption.  相似文献   
8.
Adaptation to climate change is about planning for the future while responding to current pressures and challenges. Adaptation scientists are increasingly using future visioning exercises embedded in co-production and co-development techniques to assist stakeholders in imagining futures in a changing climate. Even if these exercises are growing in popularity, surprisingly little scrutiny has been placed on understanding the fundamental assumptions and choices in scenario approaches, timeframes, scales, or methods, and whether they result in meaningful changes in how adaptation is being thought about. Here, we unpack key insights and experiences across 62 case studies that specifically report on using future visioning exercises to engage stakeholders in climate change adaptation. We focus on three key areas: 1) Stakeholder diversity and scales; 2) Tools, methods, and data, and 3) Practical constraints, enablers, and outcomes. Our results show that most studies focus on the regional scale (n = 32; 52%), involve mainly formal decision makers and employ vast array of different methods, tools, and data. Interestingly, most exercises adopt either predictive (what will happen) and explorative (what could happen) scenarios while only a fraction use the more normative (what should happen) scenarios that could enable more transformative thinking. Reported positive outcomes include demonstrated increases in climate change literacy and support for climate change adaptation planning. Unintended and unexpected outcomes include increased anxiety in cases where introduced timeframes go beyond an individual’s expected life span and decreased perceived necessity for undertaking adaptation at all. Key agreed factors that underpin co-production and equal representation, such as gender, age, and diversity, are not well reported, and most case studies do not use reflective processes to harness participant feedback that could enable more robust methodology development. This is a missed opportunity in developing a more fundamental understanding of how these exercises can effectively shift individual and collective mindsets and advance the inclusion of different viewpoints as a pathway for more equitable and just climate adaptation.  相似文献   
9.
This global spatially explicit (0.5 by 0.5 degree) analysis presents the nitrogen (N) and phosphorus (P) inputs, processing and biogeochemical retention and delivery to surface waters and river export to coastal seas according to the five shared socioeconomic pathways (SSP). Four systems are considered: (i) human system; (ii) agriculture; (iii) aquaculture; (iv) nature. Exploring the changes during 1980–2015 and 2015–2050 according to the SSPs shows that the natural nutrient sources have been declining in the past decades and will continue to decline in all SSPs in future decades due to massive land transformations, while agriculture, human sewage and aquaculture are becoming increasingly dominant (globally up to 80% of nutrient delivery). More efforts than those employed in any of the SSPs are needed to slow down the global nutrient cycles. One of the drivers of the proliferation of harmful algal blooms is the tendency towards increasing N:P ratios in global freshwaters and export to the global coastal seas; this is the result of increasing N:P in inputs in food production, more efficient biogeochemical retention of P than of N in river basins, and groundwater N legacies, which seems to be most pronounced in a united world that strives after sustainability. The diverging strategies to achieve UN Sustainable Development Goals 14 (life below water), 2 (zero hunger) and 6 (clean water and sanitation) therefore require a balanced management system for both N and P in all systems, that accounts for future nutrient legacies.  相似文献   
10.
In this paper, a preliminary data processing was made for tbe aftershock records or theZhangbei M6.2 earthquake on Jan. 10, 1998. The hypocenters of 205 earthquakes with M_L≥0.5 were located. The result shows that most aftershockS were concentrated in a more than10 km long and 5~8 km wide NE-trending beIt. The source mechanism solutions of largeraftersbocks were also calculated, from which it can be inferred that the faulted zone of themain shock is an NE-trending fault. Furthermore, the spectral analysis of P waves was made.The corner frequency is about 10 Hz.  相似文献   
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