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171.
How does forest certification contribute to boreal biodiversity conservation? Standards and outcomes in Sweden and NW Russia 总被引:2,自引:0,他引:2
Marine Elbakidze Per AngelstamKjell Andersson Mats NordbergYurij Pautov 《Forest Ecology and Management》2011,262(11):1983-1995
Forest Stewardship Council (FSC) is one of the leading forest certification schemes. While many studies concern political aspects and social outcomes of FSC, little is known about the contribution of certification to biodiversity conservation. In Europe, the Russian Federation and Sweden have the largest areas of FSC-certified forest. We assessed the potential of FSC certification for boreal biodiversity conservation in terms of standard content, and outcomes as habitat area set aside and habitat network functionality. First, we compared the biodiversity conservation indicators at different spatial scales in Swedish and Russian FSC standards. Second, focusing on one large state forest management unit in each country, we compared the areas of formally and voluntarily set aside forests for biodiversity conservation. Third, we evaluated the structural habitat connectivity by applying morphological spatial pattern analysis, and potential functional connectivity by using habitat suitability index modelling for virtual species. The Russian standard included indicators for all spatial scales of biodiversity conservation, from tree and stand to landscape and ecoregions. The Swedish standard focused mainly on stand and tree scales. The area of voluntary set-asides for FSC was similar in Sweden and Russia, while formal protection in the Russian case study was three times higher than in the Swedish one. Swedish set-aside core areas were two orders of magnitude smaller, had much lower structural and potential functional connectivity and were located in a fragmented forestland holding. We conclude that to understand the potential of FSC certification for biodiversity conservation both the standard content, and its implementation on the ground, need to be assessed. We discuss the potential of FSC certification for biodiversity conservation with different levels of ambition. We stress the need for developing rapid assessment tools to evaluate outcomes of FSC for biodiversity conservation on the ground, which could be used by forest managers and FSC-auditors toward adaptive governance and management. 相似文献
172.
Anders Roos Matti Flinkman Armas Jppinen Gran Lnner Mats Warensj 《Forest Policy and Economics》2001,3(3-4)
The strategic production decisions to improve profits for sawmills can be described in three main dimensions. More value-added production increases unit revenues, larger volumes reduce fixed costs per produced unit, and improved productivity reduces unit costs. Using data about the Swedish sawmills and cluster analysis, six groups of sawmills were defined with these strategy dimensions. Characteristics of each strategy are presented concerning ownership, location, technology, and economic indicators. The results indicate that different groups of Swedish sawmills employ different production strategies, which are reflected both in the dimensions, value-added shares, size, productivity, and by other technical and economic characteristics of the sawmills. The relationships between production strategy and profitability is also analysed and discussed. 相似文献
173.
Mats Ekevad 《Journal of Wood Science》2005,51(5):455-461
Distortions due to moisture changes during drying or in service are a major problem for construction timber. Twist, caused
mainly by the cylindrical geometry, the orthotropic nature of the wood material, and the tendency of the wood fibers to grow
in a spiral around the stem, is often regarded as the most detrimental distortion of sawn timber. There is a need for a basic
mechanical understanding of how the twist distortion arises and also a need for a simple formula to predict the amount of
twist distortion. In this article such a formula is proposed, and theory and experimental data that indicate the validity
of the formula are shown. The first term in the formula is a modification of a traditional expression which is proportional
to the mean value of the spiral grain angle in the cross section in question. The second term in the formula is new and is
proportional to the gradient of the spiral grain angle, and this term normally counteracts the first term so that a stud with
a left-handed spiral grain might achieve a right-handed twist. Linear elastic finite element method (FEM) results and comparisons
with experimental data show that the formula works well and that linear FEM calculations exaggerate the twist, which is probably
partly due to nonlinear effects. The formula could be used to predict the twist of sawn timber from measured spiral grain
angles on the log surface. 相似文献
174.
We used a four-point resistivity method to detect wood decay in living trees. A low-frequency alternating current was applied to the stem and the induced voltage measured between two points along the stem. The effective resistivity of the stem was estimated based on stem cross-sectional area. A comparison within a group of trees showed that trees with butt rot had an effective resistivity that was at least a factor of two lower than that of healthy trees. In tests on several groups of Norway spruce (Picea abies (L.) Karst.) comprising more than 300 trees in total, the method detected butt rot with high accuracy. We validated the method both by measurements and by finite element modeling and simulations. 相似文献
175.
176.
Christensen BW Troedsson MH Murchie TA Pozor MA Macpherson ML Estrada AH Carrillo NA Mackay RJ Roberts GD Langlois J 《Journal of the American Veterinary Medical Association》2006,228(8):1228-1233
CASE DESCRIPTION: A 19-year-old Thoroughbred mare was evaluated at 265 days of gestation with a markedly distended abdomen and edema of the ventral portion of the abdomen. CLINICAL FINDINGS: The uterus was distended over the pelvic rim, making transrectal palpation of the fetus impossible. Transabdominal ultrasonography revealed excessive amounts of fetal fluid. Results of analysis of fluid obtained via amnio- and allantocentesis confirmed that the amniotic cavity was large. TREATMENT AND OUTCOME: The mare was monitored for signs of weakness of the prepubic tendon and abdominal wall. The fetus and placenta were monitored for signs of stress and pending abortion. Flunixin meglumine and altrenogest were administered to the mare. Parturition was attended and occurred at 321 days' gestation. Postpartum complications in the mare included hypovolemic shock and cardiac arrhythmias. Both conditions were treated, and the mare recovered. The foal was considered small, had bilateral angular limb deformities, and was unable to nurse. The foal was given plasma for failure of passive transfer of immunity. Ten months later, the foal underwent procedures to correct limb deformities. CONCLUSIONS AND CLINICAL RELEVANCE: Hydrops conditions are rare in horses, with hydrops allantois occurring more frequently than hydrops amnion; reportedly result in fetal or neonatal death; and may result in death of or injury to the mare. Close monitoring of maternal and fetal health in combination with supportive treatment of the mare can result in the safe progression of a hydrops pregnancy and the birth of a live foal. 相似文献