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131.
Florian Diekmann Robert A. Ford S. Kent Harrison Emilie E. Regnier Ramaro Venkatesh 《Journal Of Agricultural & Food Information》2013,14(4):290-320
Giant ragweed (Ambrosia trifida L.) has become one of the most persistent and problematic weeds to farmers and allergy sufferers in North America over the last decades. This study aims to identify and assess the scholarly literature using a bibliometric analysis approach. Based on bibliographic records retrieved from the Web of Science database, the study describes the periodic growth of literature, scientific fields and journals, author productivity and collaborations, institutions and countries, and topical focus and uses article citation analysis to identify the most influential works in this research field during the period of 1903 to 2012. 相似文献
132.
Edgardo M. Latrubesse Fernando M. d'Horta Camila C. Ribas Florian Wittmann Jansen Zuanon Edward Park Thomas Dunne Eugenio Y. Arima Paul A. Baker 《水产资源保护:海洋与淡水生态系统》2021,31(12):1136-1149
- The extent and intensity of impacts of multiple new dams in the Amazon basin on specific biological groups are potentially large, but still uncertain and need to be better understood.
- It is known that river disruption and regulation by dams may affect sediment supplies, river channel migration, floodplain dynamics, and, as a major adverse consequence, are likely to decrease or even suppress ecological connectivity among populations of aquatic organisms and organisms dependent upon seasonally flooded environments.
- This article complements our previous results by assessing the relationships between dams, our Dam Environmental Vulnerability Index (DEVI), and the biotic environments threatened by the effects of dams. Because of the cartographic representation of DEVI, it is a useful tool to compare the potential hydrophysical impacts of proposed dams in the Amazon basin with the spatial distribution of biological diversity. As the impact of Amazonian dams on the biota of both rivers and periodically flooded riparian environments is severe, DEVIs from different Amazonian tributary basins are contrasted with patterns of diversity and distribution of fish, flooded forest trees and bird species.
- There is a consistent relationship between higher DEVI values and the patterns of higher species richness and endemism in all three biological groups. An assessment of vulnerability at the scale of tributary basins, the assessment of biodiversity patterns related to DEVI, and the analysis of teleconnections at basin scale, demonstrate that recent construction of dams is affecting the biota of the Amazon basin.
- The evidence presented here predicts that, if currently planned dams are built without considering the balance between energy production and environmental conservation, their cumulative effects will increase drastically and represent a major threat to Amazonian biodiversity.
133.
Therese M. Work Pete Weingartner Hugh J. Murphy Ronald Knight Business Lind Sanford Linda Best Florian I. Lauer Joe Pavek Shelley Jansky James Bryan M. D. Groskopp Charles R. Brown Richard G. Clarke John Guerard Jim Davis Rikki Sterrett John Ojala Joseph Guenthner 《American Journal of Potato Research》1989,66(11):769-790
134.
Five cultivars were studied for 3 years to estimate the genotype × environment interactions. Plant height was studied at four locations. The tuber characters, yield, type, number, and specific gravity were studied at three locations. There were no significant clone × location or clone × year interactions. The clone × year × location interaction was significant for plant height and tuber yield. The clone × replication in year and location interaction was significant for all characters studied. The theoretical variance of a clonal mean was used to determine the most efficient allocation of plots. The largest reduction in standard error of the mean was obtained by increasing locations. Comparisons of standard errors of differences in percentages of the observed mean were also made to estimate precision obtained with specific testing procedures. 相似文献
135.
Florian Delerue Maya Gonzalez Anne Atlan Sylvain Pellerin Laurent Augusto 《Annals of Forest Science》2013,70(3):219-228
Context
While many woody perennials grow and reproduce in varying environments, their ability to modify their reproductive allocation under varying resource availability is unclear.Aims
This study aimed to demonstrate the occurrence of plasticity of reproductive allocation in a pioneer woody species (Ulex europaeus).Methods
We studied seed production in 144 plants under different irradiance and population densities. We measured their basal area, their whole shoot biomass and photosynthetic biomass, and their reproductive output (number of fruits per individual and number of seeds per fruit).Results
We found that newly produced photosynthetic biomass was influenced by environmental variation, which in turn determined its reproductive output. In addition, in low light conditions investment in reproduction was more reduced than investment in growth indicating plasticity of reproductive allocation.Conclusion
These results provide the first evidence for plasticity of reproductive allocation of a woody plant. It may lead to the ability of this pioneer species to survive and to continue to reproduce even at low rates in non-optimal shady habitats and to maintain a non-empty seed bank in forest systems with long unfavourable periods between two disturbances. 相似文献136.
137.
138.
Drought effects on C,N, and P nutrition and the antioxidative system of beech seedlings depend on geographic origin 下载免费PDF全文
Florian Netzer Carolin Thöm Nevenka Celepirovic Mladen Ivankovic Saleh Alfarraj Aikaterini Dounavi Judy Simon Cornelia Herschbach Heinz Rennenberg 《植物养料与土壤学杂志》2016,179(2):135-150
In future, prolonged summer drought and heat will constitute a major risk for the cultivation of shallow‐rooting beech in Central Europe and will negatively affect the productivity of beech forests. In a pot experiment under controlled conditions, the influence of long‐term (28 d) water deprivation on nitrogen (N), carbon (C), phosphate (Pi), and ascorbate (ASC) concentrations was examined in leaves and fine roots of beech seedlings (Fagus sylvatica L.) from six provenances originating from Central Europe (Germany: Neidenstein and Illertissen, intermediate habitats), the Balkan peninsula (Croatia: Zagreb and Gospic, wet habitats), and Southeast Europe (Bulgaria: Kotel, Greece: Paikos; dry habitats). The goal of the study was to identify beech provenances well adapted to water limitation during summer drought events. Our results suggest that N might be involved in the alleviation of water scarcity, whereas Pi might become a limiting factor for forest growth during drought periods. Drought stress resulted in significant changes of ASC pools in leaves and fine roots and the ASC redox state. Under well‐watered and under drought conditions, ASC in leaves was the most important factor causing differences between the provenances examined. Finally, a link between P nutrition and the capacity of antioxidative stress defense by ascorbate could be highlighted. Based on observations from this study, beech seedlings from three origins (Paikos, Zagreb, and Neidenstein) might constitute beech provenances well adapted to water shortage in summer. This conclusion is drawn from the high potential of these provenances to alleviate oxidative stress during water shortage. 相似文献
139.
Jean‐François HOCQUETTE Carine CAPEL Valérie DAVID Daniel GUÉMENÉ Joël BIDANEL Claire PONSART Pierre‐Louis GASTINEL Pierre‐Yves Le BAIL Philippe MONGET Pierre MORMÈDE Maurice BARBEZANT Florian GUILLOU Jean‐Louis PEYRAUD 《Animal Science Journal》2012,83(7):517-528
Providing phenotypic information, which is accurate, reliable, repeatable and comparable across countries or laboratories, is critical to gain a better understanding of the relationship between genes and phenotypes. So far, it is indeed extremely difficult to combine different sources of phenotypic data from multiple origins, partly because of the variability in the methods of phenotyping. The phenotyping program of livestock involves the definition of complex phenotypes obtained from data integration at different levels (from molecules to herds), the implementation of the latest technologies to accurately characterize at high speed and low cost, the greatest number of animals in a better characterized environment, and the development and sharing of large databases for data analysis and modeling. Such a program also involves the construction of a coordinated network of research and professional facilities and a common language with shared definition of unambiguous animal traits and of methods to assess them. To this end, it will build on the ‘Animal Trait Ontology of Livestock’ (ATOL) project with the objective of defining precisely the phenotypes of interest for farm animals. Then, it will be necessary to combine an environmental information system related to animal husbandry and associated methods to capture the phenotypic differences between animals. 相似文献
140.
Florian Schnabel Elias de Melo Virginio Filho Su Xu Ian D. Fisk Olivier Roupsard Jeremy Haggar 《Agroforestry Systems》2018,92(6):1535-1549
Greater understanding of the influences on long-term coffee productivity are needed to develop systems that are profitable, while maximizing ecosystem services and lowering negative environmental impacts. We examine a long-term experiment (15 years) established in Costa Rica in 2000 and compare intensive conventional (IC) coffee production under full sun with 19 agroforestry systems combining timber and service tree species with contrasting characteristics, with conventional and organic managements of different intensities. We assessed productivity through coffee yield and coffee morphological characteristics. IC had the highest productivity but had the highest yield bienniality; in the agroforestry systems productivity was similar for moderate conventional (MC) and intensive organic (IO) treatments (yield 5.3 vs. 5.0 t ha?1 year?1). Significantly lower yields were observed under shade than full sun, but coffee morphology was similar. Low input organic production (LO) declined to zero under the shade of the non-legume timber tree Terminalia amazonia but when legume tree species were chosen (Erythrina poepiggiana, Chloroleucon eurycyclum) LO coffee yield was not significantly different than for IO. For the first 6 years, coffee yield was higher under the shade of timber trees (Chloroleucon and Terminalia), while in the subsequent 7 years, Erythrina systems were more productive; presumably this is due to lower shade covers. If IC full sun plantations are not affordable or desired in the future, organic production is an interesting alternative with similar productivity to MC management and in LO systems incorporation of legume tree species is shown to be essential. 相似文献