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181.
  • 1. The provision of Canadian and US hard, enforceable, law to authorize rapid response management of nonindigenous aquatic species originating from aquaculture, live fish sales, bait fish, and the pet trade was analysed at the provincial/state levels of government for the Atlantic, Laurentian Great Lakes, and Pacific regions of North America.
  • 2. No federal legal capacity for rapid response management exists in either country. US state legislation is generally better developed than Canadian provincial laws to manage the exotic fish trade. However, much discrepancy exists among provincial and state law regarding provisions to restrict or prohibit potentially harmful species. Aquaculture and baitfish use is generally better regulated than live fish markets and the pet fish trade in both countries. Only the state of Maine has laws authorizing rapid‐response management to control escaped exotic fish.
  • 3. Most species of nonindigenous fish arise from the aquarium, pet, and baitfish trades, and development of improved legislation containing provisions for rapid response management of escapees is warranted in all states and provinces.
  • 4. It is recommended that Canada amends the Fisheries Act to create the appropriate enabling legislation to monitor, assess risk, and deploy rapid response management of nonindigenous aquatic species, including fish that enter federal fresh and sea waters. Two recently‐introduced US Bills, S. 725 and H.R. 1350, with their explicit measures for early detection and fast action response, could, if passed into law, create provisions to control introduced nuisance species throughout North American waters. They would also create precedents for states and provinces that have most jurisdiction over aquaculture and trade in exotic fish to amend and align their laws in a complementary manner.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
182.
183.
Integration of large‐area, economically driven macro‐models and small‐area, biophysically based models in the Canadian agricultural sector was described recently in the development of a land‐use allocation model (LUAM). We have since developed and integrated an improved methodology for allocating crop area changes generated for large areas by the Canadian Regional Agricultural Model (CRAM) to much smaller Soil Landscapes of Canada (SLC) polygons. Validation of outputs showed considerable improvement. The new coefficients of determination (R2) between simulated and actual data, with previous values in brackets, were 0.69 for fodder corn (0.54), 0.88 for wheat (0.62), 0.77 for hay (0.26), 0.54 for alfalfa (not previously reported), 0.88 for soya bean (0.26) and 0.86 for grain corn (0.22). The best result was obtained for soya bean, with a normalized root mean square error (NRMSE) of 0.31%, and the poorest for alfalfa, with NRMSE = 17.34%.  相似文献   
184.
丛之华  王信胜 《安徽农业科学》2013,(29):11723-11724
森林认证已成为改善森林管理的一种重要的治理机制。文章介绍了加拿大森林认证的现状,分析了加拿大推进森林认证的措施,并借鉴加拿大推进森林认证的经验,提出我国推进森林认证的对策。  相似文献   
185.
为明确温度对白僵菌侵染烟粉虱的影响,在5 个温度(19、22、25、28、31 ℃)条件下观察研究白僵菌加拿大1
号菌株的孢子萌发率、菌丝生长速度、胞外蛋白酶及几丁质酶活性的变化情况。结果表明:28 ℃时,加拿大1 号菌株的上
述参数值均最大,对烟粉虱的致病力最高;温度过低或过高,孢子萌发率、菌丝生长速率、胞外蛋白酶及几丁质酶活性均显
著降低,对烟粉虱的致病力也显著减弱。  相似文献   
186.
分析论述了加拿大林业的管理概况,并着重对森林采伐和管理称谓于生态采伐管理的概念做了进一步讨论和评价。  相似文献   
187.
加拿大森林资源丰富,长期以来坚持以森林可持续利用的理论指导森林经营,重视林业科学技术,坚持林业科研与生产紧密结合。借鉴其经验,建议加快毕节试验区森林分类经营,加大天然林资源保护和退耕还林工程力度,发展优质高效的速生丰产用材林。  相似文献   
188.
Summary Canada imports more than 21,000 tonnes of strawberries annually, of which approximately 5,000–6,000 tonnes are frozen berries used for processing at a cost of more than $ 10 million. These could be replaced by Canadian grown fruit if improved cultivars, and suitable for mechanical harvesting, processing and fresh market adapted to canadian climatic conditions would be available. For many years producers in Quebec have grown the cultivar ‘Redcoat’ (Sparkle × Valentine) released in 1957 by Agriculture Canada, Ottawa. Redcoat is now rapidly being replaced by ‘Kent’, (`K68-58 × Raritan’) released in 1981 by Agriculture Canada, Kentville. Despite Quebec's preeminant position in Canada as a strawberry producing region, no strawberry cultivars have ever been bred specific for Quebec conditions. In 1982 a breeding program was initiated at Agriculture Canada St-Jean. This program was terminated in 1986 without any material having been tested sufficiently for release. In 1987 a joint project between McGill University and Agriculture Canada initiated to continue the breeding program and develop cultivars particularly suitable for mechanical harvesting and processing, resistant to disease and adapted to local conditions. Agriculture Canada, St-Jean-sur-Richelieu, Contribution No. 335/93.12.02R  相似文献   
189.
190.
为探索冀东冷棚三种三收高效栽培模式,引进番茄保粉1号、1857、西芹文图拉新品种,与当地传统品种番茄L402、L400、芹菜玻璃脆对比.结果表明:新品种具有优良的商品品质和价格优势.改进当地普通大冷棚,设计出结构合理、投资少、效益高的无立柱、无后墙型加苫冷棚,生产出的番茄、芹菜春提前,秋延后,补充市场淡季,延长蔬菜供应期.三种三收模式单棚产值(400 m2)达11 156.30元,比普通大冷棚两种两收模式单棚总产值增加4 245.90元,此模式具有产量高、品质优、效益高、推广前景广阔等特点.  相似文献   
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