全文获取类型
收费全文 | 251篇 |
免费 | 34篇 |
国内免费 | 1篇 |
专业分类
林业 | 31篇 |
农学 | 2篇 |
基础科学 | 1篇 |
34篇 | |
综合类 | 27篇 |
农作物 | 14篇 |
水产渔业 | 26篇 |
畜牧兽医 | 119篇 |
园艺 | 9篇 |
植物保护 | 23篇 |
出版年
2024年 | 1篇 |
2023年 | 8篇 |
2022年 | 8篇 |
2021年 | 13篇 |
2020年 | 17篇 |
2019年 | 17篇 |
2018年 | 11篇 |
2017年 | 20篇 |
2016年 | 13篇 |
2015年 | 8篇 |
2014年 | 11篇 |
2013年 | 6篇 |
2012年 | 21篇 |
2011年 | 24篇 |
2010年 | 13篇 |
2009年 | 11篇 |
2008年 | 16篇 |
2007年 | 11篇 |
2006年 | 14篇 |
2005年 | 4篇 |
2004年 | 13篇 |
2003年 | 7篇 |
2002年 | 2篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 4篇 |
1993年 | 1篇 |
1990年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1974年 | 1篇 |
1902年 | 1篇 |
1900年 | 1篇 |
1883年 | 1篇 |
排序方式: 共有286条查询结果,搜索用时 898 毫秒
41.
Gordon H Copp J Robert Britton Julien Cucherousset Emili García‐Berthou Ruth Kirk Edmund Peeler Saulius Stakėnas 《Fish and Fisheries》2009,10(3):252-282
A popular species for food and sport, the European catfish (Silurus glanis) is well‐studied in its native range, but little studied in its introduced range. Silurus glanis is the largest‐bodied freshwater fish of Europe and is historically known to take a wide range of food items including human remains. As a result of its piscivorous diet, S. glanis is assumed to be an invasive fish species presenting a risk to native species and ecosystems. To assess the potential risks of S. glanis introductions, published and ‘grey’ literature on the species’ environmental biology (but not aquaculture) was extensively reviewed. Silurus glanis appears well adapted to, and sufficiently robust for, translocation and introduction outside its native range. A nest‐guarding species, S. glanis is long‐lived, rather sedentary and produces relatively fewer eggs per body mass than many fish species. It appears to establish relatively easily, although more so in warmer (i.e. Mediterranean) than in northern countries (e.g. Belgium, UK). Telemetry data suggest that dispersal is linked to flooding/spates and human translation of the species. Potential impacts in its introduced European range include disease transmission, hybridization (in Greece with native endemic Aristotle’s catfish [Silurus aristotelis]), predation on native species and possibly the modification of food web structure in some regions. However, S. glanis has also been reported (France, Spain, Turkmenistan) to prey intensively on other non‐native species and in its native Germany to be a poor biomanipulation tool for top‐down predation of zooplanktivorous fishes. As such, S. glanis is unlikely to exert trophic pressure on native fishes except in circumstances where other human impacts are already in force. In summary, virtually all aspects of the environmental biology of introduced S. glanis require further study to determine the potential risks of its introduction to novel environments. 相似文献
42.
43.
Relationships between individual movement,trophic position and growth of juvenile pike (Esox lucius)
下载免费PDF全文
![点击此处可从《Ecology of Freshwater Fish》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Marina J. Nyqvist Julien Cucherousset Rodolphe E. Gozlan J. Robert Britton 《Ecology of Freshwater Fish》2018,27(1):398-407
Variation in movement between individuals can have important ecological effects on populations and ecosystems, yet the factors driving differences in movement and their consequences remain poorly understood. Here, individual variability in the movements of juvenile (age 0 + and 1 + year) pike Esox lucius was assessed using passive integrated transponder (PIT) telemetry in off‐channel nursery areas over a 26‐ month period. Differences in the movement patterns of individuals were tested against their body sizes, ages, growth rates and trophic positions using data collected through a combination of catch‐and‐release sampling and stable isotope analyses. Results revealed that variation in movement between individuals was affected by age, with 1 + individuals moving more than individuals of age 0 + , but not length. Individuals whose TP was low on their initial capture event moved significantly less than those with a higher initial TP. Individuals that moved more grew faster and achieved a higher final TP. These results suggest that higher activity (i.e., increased movement) increases resource acquisition that enhances growth rates, which could ultimately maximise individual performances. 相似文献
44.
45.
46.
Quantitative estimates of freshwater fish stocking practices by recreational angling clubs in France
Julien Cucherousset Rémy Lassus Carsten Riepe Paul Millet Frédéric Santoul Robert Arlinghaus Mathieu Buoro 《Fisheries Management and Ecology》2021,28(4):295-304
Although freshwater fish stocking is widely used by managers, quantitative assessments of stocking practices are lacking in many countries. The general objective of the present study was to determine the quantity and characteristics of fish stocking in metropolitan France. Using a survey-based approach, stocking practices for 2013 by recreational angling clubs in France were quantified, which represented the bulk of fish stocking undertaken in that year. Stocking was found to be practiced by 88.6% of angling clubs in France, representing, on average, 65% of their annual budget. Overall, 22 species were stocked, including 13 native and nine non-native species, with strong variations among species in terms of life stages and body sizes used for stocking. Using Bayesian modelling, a total biomass of 2.029 t, representing approximately 90 million fishes, was estimated to be stocked in France in 2013. In terms of biomass, the most widely stocked species were rainbow trout Oncorhynchus mykiss (Walbaum), brown trout Salmo trutta L., roach Rutilus rutilus (L.), common carp Cyprinus carpio L. and northern pike Esox lucius L. A stocking volume of approximately 60 fishes or 1.5 kg of fish biomass per angler per year seems commonplace in industrialised countries for which data are available. 相似文献
47.
Nicolas Guillerault Géraldine Loot Simon Blanchet Paul Millet Camille Musseau Julien Cucherousset Frédéric Santoul 《Fisheries Management and Ecology》2021,28(5):486-495
Stocking and electrofishing occurrence and abundance data for northern pike Esox lucius L. in >3800 km of French rivers across 7 years were compared to assess the effect of recreational fisheries stocking programmes on wild pike populations. A positive relationship was found between the additive effect of stocking and the size of the stocked pike. However, the stocking programmes implemented in France by recreational fishery managers from 2008 to 2013 increased the probability of pike occurring in the river network, without increasing abundance in well-established pike populations, because pike stocked in their early-life stages were used in most of the stocking programmes. 相似文献
48.
Use of cryopoor plasma for albumin replacement and continuous antimicrobial infusion for treatment of septic peritonitis in a dog
下载免费PDF全文
![点击此处可从《Journal of Veterinary Emergency and Critical Care》网站下载免费的PDF全文](/ch/ext_images/free.gif)
49.
Estelle Noyer Barbara Lachenbruch Jana Dlouhá Catherine Collet Julien Ruelle François Ningre Meriem Fournier 《Annals of Forest Science》2017,74(2):46
Key message
The position of trees in the canopy impacts xylem structure and its inter-annual variation. After canopy release, the increase in the hydraulic conductivity of growth rings was driven by an increase in radial growth in large trees, and by both an increase in radial growth and changes in xylem structure in saplings.Context
Forest canopies are frequently subjected to disturbances that allow understory trees to access the upper canopy. The effect of canopy release on xylem anatomy has been assessed in juvenile trees and saplings, while the potential acclimation of larger trees remains poorly documented.Aims
We estimated the potential hydraulic conductivity of growth rings in large understory trees compared to overstory trees, and evaluated the responses to canopy release in large trees and in saplings.Methods
We recorded radial growth, wood density, and vessel structure in beech trees according to their position within the canopy and their size. Xylem traits were followed during 6 years after canopy release for large trees, and during 2 years for saplings. Vessel diameter and frequency as well as ring area were used to compute the potential annual ring hydraulic conductivity.Results
Large understory trees displayed lower radial growth increments and lower potential annual ring hydraulic conductivity than overstory trees. After canopy release, potential annual ring hydraulic conductivity increased in large trees, due exclusively to increased radial growth without any change in specific hydraulic conductivity. It increased in saplings due to both increased radial growth and increased specific conductivity.Conclusion
Tree size impacted xylem structure and resulted in plasticity of the potential hydraulic conductivity of the annual tree ring following canopy release.50.