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91.
Insights from experimental economics on local cooperation in a small-scale fishery management system
Shankar Aswani Georgina G. Gurney Sara Mulville Jaime Matera Michael Gurven 《Global Environmental Change》2013,23(6):1402-1409
Cooperation is central to collective management of small-scale fisheries management, including marine protected areas. Thus an understanding of the factors influencing stakeholders’ propensity to cooperate to achieve shared benefits is essential to accomplishing successful collective fisheries management. In this paper we study stakeholders’ cooperative behavioral disposition and elucidate the role of various socio-economic factors in influencing it in the Roviana Lagoon, Western Solomon Islands. We employed a Public Goods Game from experimental economics tailored to mimic the problem of common pool fisheries management to elucidate peoples’ cooperative behavior. Using Ostrom's framework for analyzing social-ecological systems to guide our analysis, we examined how individual-scale variables (e.g., age, education, family size, ethnicity, occupational status, personal norms), in the context of village-scale variables (e.g., village, governance institutions, group coercive action), influence cooperative behavior, as indexed by game contribution. Ostrom's framework provides an effective window for conceptually peeling back the various socio-economic and governance layers which influence cooperation within these communities. The results of our research show that the most important resource user characteristics influencing cooperative behavior were age, occupation and beliefs about giving access to others to fish for commercial gain. Through elucidating the factors affecting stakeholders’ propensity to cooperate to achieve shared benefits, our analysis provides guidance in understanding cooperation in relation to collective management of marine resources. 相似文献
92.
Jaime Orlando Martínez Eduardo López Ramos 《Journal of South American Earth Sciences》2011,31(2-3):342-343
93.
Damage and management of cyclone Sidr-affected homestead tree plantations: a case study from Patuakhali, Bangladesh 总被引:1,自引:0,他引:1
Md. Zamiul Haq Mahbub Robbani Mohammad Ali Md. Mainul Hasan Md. Mahmudul Hasan Md. Jashim Uddin Monjila Begum Jaime A. Teixeira da Silva Xiao-Ying Pan Md. Rezaul Karim 《Natural Hazards》2012,64(2):1305-1322
Geographically, Bangladesh is considered to be one of the most cyclone-prone areas in the world. The super cyclone Sidr in 2007 was one of the most devastating disasters to have ever occurred in Bangladesh, having wind speeds of 223?km/h with a tidal surge of 6.1?C7.6?m high. In order to draw a pre- and post-Sidr damage and management scenario, a survey was conducted at Dumki upazila, Patuakhali district in Bangladesh with a pretested questionnaire. Primary data were collected through a questionnaire, while secondary data were collected from pertinent offices as well as academic journals. The major focus of this study was to assess the state of pre-Sidr tree plantations (woody and fruit trees), the devastation caused by Sidr on these tree plantations, and post-Sidr recovery and further sustainable management initiatives to counteract a possible future neo-Sidr. The post-Sidr study showed that about 16.84 million woody and fruit trees were uprooted by Sidr. A total of 3,120 rain tree (Samanea saman L.), 7,548 mahogany (Swietenia mahagoni L.), 1,444 royal siris (Albizzia richardiana L.), 702 white siris (Albizzia procera L.), 1,214 mango (Mangifera indica L.), 1,092 coconut (Cocos nucifera L.), 1,380 jackfruit (Artocarpus heterophyllus L.), and 7,640 betel nut (Areca catechu L.) trees were sampled among which 922, 1,662, 382, 210, 106, 38, 362, and 1,652 trees, respectively, were markedly damaged by Sidr. Sexually propagated woody trees with a damaged taproot were vulnerable to heavy wind during the cyclone. Fruit trees were more resistant to the cyclone than other types of trees, and the lack of proper tree training and pruning was one of the principal causes of the severe damage to woody trees. Hence, plantations of woody tree saplings with damaged taproots are strongly discouraged. However, proper training and pruning of homestead trees together with plantation of fruit trees rather than woody trees is suggested as a possible effective management strategy to protect the homestead ecosystem from devastation by future cyclones in Bangladesh. 相似文献
94.
Characterizing the spatial patterns of variability is a fundamental aspect when investigating what could be the causes behind the spatial spreading of a set of variables. In this paper, a large multivariate dataset from the southeast of Belgium has been analyzed using factorial kriging. The purpose of the study is to explore and retrieve possible scales of spatial variability of heavy metals. This is achieved by decomposing the variance-covariance matrix of the multivariate sample into coregionalization matrices, which are, in turn, decomposed into transformation matrices, which serve to decompose each regionalized variable as a sum of independent factors. Then, factorial cokriging is used to produce maps of the factors explaining most of the variance, which can be compared with maps of the underlying lithology. For the dataset analyzes, this comparison identifies a few point scale concentrations that may reflect anthropogenic contamination, and it also identifies local and regional scale anomalies clearly correlated to the underlying geology and to known mineralizations. The results from this analysis could serve to guide the authorities in identifying those areas which need remediation. 相似文献
95.
María NAJARRO Enrique PE?ALVER Ricardo PéREZ-DE LA FUENTE Jaime ORTEGA-BLANCO Cesar MENOR-SALVáN Eduardo BARRóN Carmen SORIANO Idoia ROSALES Rafael LóPEZ DEL VALLE Francisco VELASCO Fernando TORNOS Véronique DAVIERO-GOMEZ Bernard GOMEZ Xavier DELCLòS 《《地质学报》英文版》2010,84(4):959-976
<正>El Soplao outcrop,an Early Cretaceous amber deposit recently discovered in northern Spain (Cantabria),has been shown to be the largest site of amber with arthropod inclusions that has been found in Spain so far.Relevant data provided herein for biogeochemistry of the amber,palynology,taphonomy and arthropod bioinclusions complement those previously published.This set of data suggests at least two botanical sources for the amber of El Soplao deposit.The first(type A amber)strongly supports a source related to Cheirolepidiaceae,and the second(type B amber)shows non-specific conifer biomarkers.Comparison of molecular composition of type A amber with Frenelopsis leaves(Cheirolepidiaceae)strongly suggests a biochemical affinity and a common botanical origin.A preliminary palynological study indicates a regional high taxonomical diversity,mainly of pteridophyte spores and gymnosperm pollen grains.According to the preliminary palynological data,the region was inhabited by conifer forests adapted to a dry season under a subtropical climate.The abundant charcoalified wood associated with the amber in the same beds is evidence of paleofires that most likely promoted both the resin production and an intensive erosion of the litter,and subsequent great accumulation of amber plus plant cuticles.In addition,for the first time in the fossil record, charcoalified plant fibers as bioinclusions in amber are reported.Other relevant taphonomic data are the exceptional presence of serpulids and bryozoans on the surfaces of some amber pieces indicating both a long exposure on marine or brackish-water and a mixed assemblage of amber.Lastly,new findings of insect bioinclusions,some of them uncommon in the fossil record or showing remarkable adaptations,are reported.In conclusion,a documented scenario for the origin of the El Soplao amber outcrop is provided. 相似文献
96.
Cement-bentonite interactions will occur in deep geological repositories for high level radioactive waste. We performed laboratory experiments in order to constrain some previous geochemical and mineralogical uncertainties in the formation of secondary minerals in the high pH reaction of FEBEX bentonite at moderate temperatures.The reactivity of a Mg-homoionic FEBEX bentonite was studied at 25, 60 and 90 °C in batch reactors using two solutions representative of short and long time evolution stages of cement degradation. These solutions were periodically renewed in order to maintain a constant pH regime for a period of almost 2 years.Chabazite and merlinoite were observed to be the main zeolites that formed at 60 °C, while merlinoite was the dominant zeolite formed at 90 °C with the hyperalkaline (K-Na-OH) solution. The alkaline experiments (Ca-OH solution) showed minor reactivity and negligible mineralogical alteration, but the overall results suggest that the reaction tends to equilibrium conditions between C-S-H and montmorillonite at high temperature and metastable conditions at low temperature. The montmorillonite dissolution rates were calculated for all experiments, showing good agreement with previous calculations. 相似文献
97.
Eduardo Gonzlez-Partida Antoni Camprubí Francisco Gonzlez-Snchez Jaime Snchez-Torres 《Journal of Geochemical Exploration》2006,89(1-3):143
The most important deposit in the Plomosas–Rosario district, Sinaloa, is the vein tract named Plomositas–Plomosas–Los Arcos. These are NNW–SSE striking veins hosted in rocks of the Lower Volcanic Supergroup (LVS), and also in rocks at the bottom of the Upper Volcanic Supergroup (UVS). Both supergroups belong to the Sierra Madre Occidental. These veins evolved from an early intermediate sulfidation stage (1), rich in base metal sulfides, to a low sulfidation stage (2), rich in silver sulfides and sulfosalts. There is also a 45 m-wide stockwork with native silver and gold. Stage 1 is found in the deeper portion of the veins whereas stage 2 is found in the most shallow portion of the deposit. These stages record fluid inclusion salinities ranging from 7 to 12 wt.% NaCl equiv., and from 0.2 to 3.5 wt.% NaCl equiv., respectively. Homogenization temperatures range from 120 °C for surface samples to 200 °C at a depth of 320 m. The low homogenization temperatures recorded, and the dispersion of veins within host rocks as veinlets, suggest that this deposit formed at shallow depths and was probably blind. 相似文献
98.
Jaime Gmez-Gutirrez Leah R. Feinberg Tracy C. Shaw William T. Peterson 《Deep Sea Research Part I: Oceanographic Research Papers》2007,54(12):2145-2169
Brood sizes of 1259 adult female Euphausia pacifica and Thysanoessa spinifera were measured during 48 h incubations (10 °C, ±0.5 °C) on 27 oceanographic cruises between July 1999 and September 2004. The data set includes measurements from several stations off Newport, Oregon (Newport Hydrographic line, 44°39′N) made over a 5-year period and measurements from 14 more extensive cruises at stations representative of continental shelf, slope, and oceanic waters off Oregon and California, USA. E. pacifica had similar brood sizes at inshore (<200 m) and offshore (>200 m) stations with an average of 151 and 139 eggs brood−1 fem−1, respectively. T. spinifera brood sizes were considerably higher at inshore stations—particularly at Heceta Bank (44°N) and south of Cape Blanco (42°50′N)—than at offshore stations, 155 and 107 eggs brood−1 fem−1, respectively. Average brood sizes of E. pacifica increased during the study period, from 125 (in 2000) to 171 eggs brood−1 fem−1 (in 2003). Average percentage of carbon weight invested in spawning (reproductive effort) was higher in E. pacifica (14%) than in T. spinifera (6%), because both species have similar brood size but T. spinifera females are larger than E. pacifica females and produce smaller eggs. Reproductive effort for both species was higher during summer 2002, probably associated with anomalous cool subarctic waters and high chl-a concentration observed during that summer. Brood sizes and chl-a values remained relatively high in 2003–2004 compared to the 1999–2001 period. Geographical and temporal variability in brood sizes for both species were significantly correlated with in situ measurements of chl-a concentration but not with sea surface temperature. No gravid females were collected during late autumn and winter cruises, thus the spawning season along the Oregon coast appears to extend from March through September for both species. However, T. spinifera usually starts reproductive activity earlier in the spring (March) than E. pacifica. Both species had their highest brood sizes in summer during the period of most intense upwelling, which is associated with an increase in regional phytoplankton standing stock. 相似文献
99.
Rogrio L. Ferreira Filipe R. Ceia Teresa C. Borges Jaime A. Ramos Alan B. Bolten 《Marine Ecology》2021,42(1):e12636
Within the same population, nesting green turtles (Chelonia mydas) might exploit different niches by exhibiting polymorphic foraging strategies and/or inhabiting geographically distinct foraging areas. This is crucial information for the conservation of this species. Here, we used stable carbon and nitrogen isotope ratios (δ13C and δ15N) to test for differences in a population of green turtles nesting on Príncipe Island (1°37′N; 7°24?′E), Central Africa. A total of 60 nesting females were sampled on the two main nesting beaches of the island in December 2012. Minimum curved carapace length (CCL) was recorded, and δ13C and δ15N values were measured in the epidermis of each individual. Overall, CCL varied from 87.0 to 108.0 cm (mean ± SD =100.0 ± 5.1), δ13C values from ?19.4 to ?8.6‰ (?17.3 ± 1.8) and δ15N values from 7.9 to 17.3‰ (13.6 ± 1.5). Despite the large variation in both isotopic ratios, their distributions were unimodal, showing an absence of polymorphic foraging strategies and isotopically distinct foraging areas. However, smaller females (< median, 100.8 cm) occupied a much larger isotopic niche (i.e., four times greater) than larger females. These results suggest that nesting green turtles may forage opportunistically on the resources available in each of their foraging home ranges, with smaller females venturing to more isotopic‐diversified areas and/or exhibiting broader foraging strategies than larger females. In addition, and in accordance with other studies, findings suggest that the foraging grounds used by the Príncipe green turtle nesting females are distributed mainly throughout the Gulf of Guinea. 相似文献
100.
Hydrochemistry and origins of mineralized waters in the Puebla aquifer system,Mexico 总被引:1,自引:1,他引:0
Significant upward movement of mineralized water takes place in the Puebla aquifer system. Preferential groundwater flow paths
related to the geological structure and the lowering of the potentiometric surface are suspected to be the prime factors for
this intrusion. A combined approach of geochemical and isotope analyses was used to assess the sources of salinity and processes
that are controlling the changes in groundwater chemical composition in the Puebla aquifer. Geochemical and isotope data indicate
that the likely source of increased solutes is mineralized water from the dissolution of evaporites of the Cretaceous age
at the base of the Upper deep aquifer, which is deeper than the intakes of the shallow wells. Dedolomitization and cation
exchange seems also to occur along flow paths where sulphate concentrations tend to increase. The deep regional flow paths
controls the chemical stratification of groundwater in response to decreased heads through interconnecting vertical and horizontal
pathways, such as in the Fosa Atlixco. The results also suggest that high sulphate concentrations originating in the Lower
deep aquifer are currently affecting shallow production wells. It is concluded that hydrodynamic aspects together with hydrogeochemical
characteristics need to be taken into account to correctly explain the hydrochemical evolution in the stratified aquifer. 相似文献