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91.
春末夏初南亚高压的形成过程及其与ENSO事件的联系   总被引:2,自引:1,他引:1  
利用ERA-Interim再分析资料,分析了春末夏初南亚高压建立过程的气候特征和可能机制,并讨论了ENSO事件冷、暖位相对南亚高压建立过程年际变化的影响。结果表明,第24候,气候平均的南亚高压形成于中南半岛东南部的对流层高层,这与菲律宾群岛南部和中南半岛局地对流的加强有关。一方面,菲律宾群岛南部对流加强能够在其北部产生负涡度源,在高空热带东风急流的作用下,其下游的南海地区出现负涡度,相应地出现闭合的高空反气旋,南亚高压初步形成。另一方面,中南半岛局地对流令南亚高压中心加强发展,并使其最终位于中南半岛上空。春末夏初菲律宾群岛附近对流的经向摆动决定了南亚高压的形成位置,而中南半岛局地对流的强度则控制着南亚高压的加强北抬。由于菲律宾南部和中南半岛的局地对流都受ENSO事件影响,因此在ENSO事件的冷、暖位相下,南亚高压的形态和位置在其建立过程中差异明显。在暖事件发生后,热带对流在加里曼丹岛以东发展,南亚高压形成于苏门答腊群岛北部至泰国湾上空,此时中南半岛对流偏弱,限制了南亚高压的北抬发展;而在冷事件发生后,热带对流在菲律宾群岛中部加强,同时南亚高压形成于中南半岛中部上空,随后中南半岛对流迅速加强,令南亚高压明显西伸北抬。因此,ENSO事件的冷、暖位相对春末夏初南亚高压的形成位置有显著影响。  相似文献   
92.
The outsourcing and offshoring of services to developing countries has created new opportunities for economic development for countries in the global South. This paper looks at the scope for agency of local institutional actors in the investment attraction of business process outsourcing companies. Drawing on empirical work from the Philippines, an analysis of the process of integrating lower‐tier cities into global service production networks is presented. Specifically, the roles of local institutional actors in facilitating FDI attraction and strategically coupling local assets with the needs of multinational service corporations are discussed. Two contrasting cases, the cities of Baguio and Bacolod, show that considerable scope for intervention rests with local institutional actors. The findings have implications for policymaking and research concerned with the newest phase of outsourcing and offshoring in developing countries.  相似文献   
93.
《Marine pollution bulletin》2013,76(1-2):133-139
Effective control of outbreaks of Acanthaster planci represents the most immediate and practical intervention to reverse sustained declines in coral cover on reefs in the Indo-Pacific. This study explored the minimum doses of oxbile, oxgall, and thiosulfate-citrate-bile-sucrose agar (TCBS) that result in reliable and comprehensive mortality when injected into adult A. planci. The minimum doses required to induce 100% mortality among starfish (n = 10) were 4 g l−1 of oxbile, 8 g l−1 of oxgall and 22 g l−1 of TCBS. Moreover, there was no evidence of unintended side effects for other coral reef organisms (e.g., scleractinian corals, echinoderms and fishes) when using oxbile, oxgall, or TCBS at minimum doses. The effectiveness of peptones in killing crown-of-thorns starfish was also tested, but inconsistency in the results revealed that these proteins are unreliable.  相似文献   
94.
Abstract

The design and development of global digital databases and their integrated use in studies of terrestrial sources and sinks of trace gases are discussed. Generic design characteristics that expand the utility of these databases are outlined including: hierarchical classification systems that provide for encoding and accessing data at several levels of detail, and fine spatial and thematic resolution which accommodate adaptations to a broad base of applications. The discussion follows the sequence of (1) developing primary databases on major surface characteristics, (2) selectively integrating combinations of data bases to produce secondary data sets of source categories, and (3) combining information on source categories with fluxes to produce tertiary data sets of emissions. These procedures are demonstrated with the example of estimating and evaluating alternative global methane emissions from natural wetlands.  相似文献   
95.
This paper empirically tracks the Philippine (policy) path following the mantra of economic globalization over the past 25 years. Specifically, it investigates the resulting regional growth‐inequality relationships and development footprints accompanying the restructuring of political economy and livelihoods. The Philippine case thereby shows how globalization can simultaneously cause the selective dismantling of (economic) barriers and enhancement of mobility and growth, as well as a deterioration of socioeconomic inequalities in space and society. In an increasingly deregulated and contested environment these development divides do not just pose serious threats to regional balance and national cohesion but, ultimately, undermine state capacity to achieve avowed goals of inclusive growth, stability and equality for citizens.  相似文献   
96.
This paper aims to evaluate mariculture as sustainable livelihood diversification option for coastal fishers in the Philippines and guide policy development in this direction. Mariculture in the Philippines refers to the culture of finfishes, shellfish, seaweeds and other commodities in cages, pens, stakes and rafts in marine environment. This paper evaluates the biophysical and socioeconomic contexts in which mariculture operate. Ten years after launching the first mariculture park organized and managed by the country's government fishery agency, and the nationwide promotion of this program, only 273 ha or 0.54% of the 50,150 ha total area planned for development has been established. Mariculture has not met its expected results due to a number of problems. This paper revisits the policies, organization, governance and administration of mariculture parks in the country. It also discusses the issues and challenges with mariculture as a livelihood diversification option within the context of ecosystems approach to fisheries management in the Philippines.  相似文献   
97.
Intellectual property is increasingly a key item on the US–Japanese–European trade agenda, and the globalisation of the US patent standard, which includes patents on plants and processes, has become a key objective of ‘information-rich’ corporations and countries. While social movements act against the legal structures and spaces of knowledge associated with privatised knowledge, they also work to construct alternatives both through the development of practical alternatives such as seed-saving networks and the articulation of new discourses such as Farmers’ Rights. In doing so, farmers’ organisations are actively creating and maintaining spaces of alternative knowledges and formulations of property. The articulation of Farmers’ Rights by social movements as a response to intellectual property is a way both of resisting regimes of intellectual property and of creating a normative framework within which claims to intellectual property are made obsolete. Drawing from empirical work based in the Philippines, I propose a concept, woven space, which refers to the diverse and overlapping alternatives and resistances that emerge from the situated and embodied struggles taking place around the world to form a differently imagined and realised global. This is a decentralised, networked space, rich with experience, shared belief, and possibilities for shared action.  相似文献   
98.
Water level fluctuations due to reservoir operations often cause spatial and temporal differences in water chemistry, which in turn can have considerable biological effects. Nonetheless, few studies have investigated the effects of fluctuating water levels on water quality and benthic macroinvertebrates in reservoirs in tropical countries, and none in the Philippine archipelago. We investigated the littoral zone of a Philippine reservoir subject to strong water level fluctuations and determined whether (i) water quality and macroinvertebrate community health is reduced when water levels are low, (ii) water quality declines with increasing water depth regardless of the overall water level, and (iii) water quality and community health decrease more strongly with water depth during low water level periods. Our study included five sites and four depths at each site, with three collections each during high and low water levels. Low water levels may have negatively affected four water quality and 10 biological metrics, whereas depth may have negatively affected two water quality and five biological metrics. Significant overall water levels by depth interactions were detected for four common taxa but none for water physicochemistry. Our findings show that tropical reservoirs may experience reduced water quality at low water levels, which can affect their biodiversity and potentially their ecological functioning.  相似文献   
99.
An observational study covering the period 1950–2002 examines a seasonal reversal in the ENSO rainfall signal in the north-central Philippines. In boreal Summer of El Niño (La Niña) events, above (below) average rainfall typically occurs in this area. Rainfall anomalies of opposite sign develop across the country in the subsequent fall. This study investigates the seasonal evolution of the anomalous atmospheric circulation over the western North Pacific (WNP) during both El Niño and La Niña and places these features in the context of the large-scale evolution of ENSO events, including an analysis of changes in tropical cyclone activity affecting the Philippines. The results show that during boreal summer of El Niño (La Niña) events, a relatively narrow, zonally elongated band of enhanced (reduced) low-level westerlies develops across the WNP which serves to increase (decrease) the summer monsoon flow and moisture flux over the north-central Philippines and is associated with an increase (decrease) in the strength of the WNP monsoon trough via the anomalous relative vorticity. Tropical cyclone activity is shown to be enhanced (reduced) in the study region during boreal summer of El Niño (La Niña) events, which is related to the increase (decrease) of mid-level atmospheric moisture, as diagnosed using a genesis potential index. The subsequent evolution shows development of an anomalous anticyclone (cyclone) over the WNP in El Niño (La Niña) and the well-known tendency for below (above) average rainfall in the fall. Prolonged ENSO events also exhibit seasonal rainfall sign reversals in the Philippines with a similar evolution in atmospheric circulation.  相似文献   
100.
Scuba diving tourism has the potential to be a sustainable source of income for developing countries. Around the world, tourists pay significant amounts of money to see coral reefs or iconic, large animals such as sharks and manta rays. Scuba diving tourism is broadening and becoming increasingly popular, a novel type of scuba diving which little is known about, is muck diving. Muck diving focuses on finding rare, cryptic species that are seldom seen on coral reefs. This study investigates the value of muck diving, its participant and employee demographics and potential threats to the industry. Results indicate that muck dive tourism is worth more than USD$ 150 million annually in Indonesia and the Philippines combined. It employs over 2200 people and attracts more than 100,000 divers per year. Divers participating in muck dive tourism are experienced, well-educated, have high incomes, and are willing to pay for the protection of species crucial to the industry. Overcrowding of dive sites, pollution and conflicts with fishermen are reported as potential threats to the industry, but limited knowledge on these impacts warrants further research. This study shows that muck dive tourism is a sustainable form of nature based tourism in developing countries, particularly in areas where little or no potential for traditional coral reef scuba diving exists.  相似文献   
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