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绿肥可以解决有机肥源不足的困难,减少化肥用量,节省成本和能源消耗,改善土壤环境,提高土壤肥力和地力;提高作物产量和产品质量;促进畜牧业的发展。本文根据广东的实际,指出广东的现代化农业需要大种绿肥,也可以大种绿肥。要使广东的绿肥生产得到恢复和发展,必须抓好如下的措施:从战略高度来认识绿肥的重要性;加强领导,把它提到重要的议事日程上来;广泛开展试验示范,并加强宣传发动;增加经济投入,省、市、县各级要设立绿肥种子繁育和经营风险金。 相似文献
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KATE A. HARDWICK PEGGY FIEDLER LYNDON C. LEE BRUCE PAVLIK RICHARD J. HOBBS JAMES ARONSON MARTIN BIDARTONDO ERIC BLACK DAVID COATES MATTHEW I. DAWS KINGSLEY DIXON STEPHEN ELLIOTT KERN EWING GEORGE GANN DAVID GIBBONS JOACHIM GRATZFELD MARTIN HAMILTON DAVID HARDMAN JIM HARRIS PAT M. HOLMES MEIRION JONES DAVID MABBERLEY ANDREW MACKENZIE CARLOS MAGDALENA ROBERT MARRS WILLIAM MILLIKEN ANTHONY MILLS EIMEAR NIC LUGHADHA MARGARET RAMSAY PAUL SMITH NIGEL TAYLOR CLARE TRIVEDI MICHAEL WAY OLIVER WHALEY STEPHEN D. HOPPER 《Conservation biology》2011,25(2):265-275
Abstract: Many of the skills and resources associated with botanic gardens and arboreta, including plant taxonomy, horticulture, and seed bank management, are fundamental to ecological restoration efforts, yet few of the world's botanic gardens are involved in the science or practice of restoration. Thus, we examined the potential role of botanic gardens in these emerging fields. We believe a reorientation of certain existing institutional strengths, such as plant‐based research and knowledge transfer, would enable many more botanic gardens worldwide to provide effective science‐based support to restoration efforts. We recommend botanic gardens widen research to include ecosystems as well as species, increase involvement in practical restoration projects and training practitioners, and serve as information hubs for data archiving and exchange. 相似文献
325.
Pierre Michel Forget Pedro Jordano Joanna E. Lambert Anna Traveset S. Joseph Wright Katrin Böhning‐Gaese 《Conservation biology》2012,26(6):1072-1081
Animal‐mediated seed dispersal is important for sustaining biological diversity in forest ecosystems, particularly in the tropics. Forest fragmentation, hunting, and selective logging modify forests in myriad ways and their effects on animal‐mediated seed dispersal have been examined in many case studies. However, the overall effects of different types of human disturbance on animal‐mediated seed dispersal are still unknown. We identified 35 articles that provided 83 comparisons of animal‐mediated seed dispersal between disturbed and undisturbed forests; all comparisons except one were conducted in tropical or subtropical ecosystems. We assessed the effects of forest fragmentation, hunting, and selective logging on seed dispersal of fleshy‐fruited tree species. We carried out a meta‐analysis to test whether forest fragmentation, hunting, and selective logging affected 3 components of animal‐mediated seed dispersal: frugivore visitation rate, number of seeds removed, and distance of seed dispersal. Forest fragmentation, hunting, and selective logging did not affect visitation rate and were marginally associated with a reduction in seed‐dispersal distance. Hunting and selective logging, but not fragmentation, were associated with a large reduction in the number of seeds removed. Fewer seeds of large‐seeded than of small‐seeded tree species were removed in hunted or selectively logged forests. A plausible explanation for the consistently negative effects of hunting and selective logging on large‐seeded plant species is that large frugivores, as the predominant seed dispersers for large‐seeded plant species, are the first animals to be extirpated from hunted or logged forests. The reduction in forest area after fragmentation appeared to have weaker effects on frugivore communities and animal‐mediated seed dispersal than hunting and selective logging. The differential effects of hunting and selective logging on large‐ and small‐seeded tree species underpinned case studies that showed disrupted plant‐frugivore interactions could trigger a homogenization of seed traits in tree communities in hunted or logged tropical forests. Meta Análisis de los Efectos de la Perturbación Humana sobre la Dispersión de Semillas por Animales 相似文献
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参照国家标准《公共场所卫生指标及限值要求》(GB 37488—2019),在游泳池布设6个采样点,采用计算机远程实时在线监测游泳池水pH值、游离余氯、细菌总数、大肠菌群、尿素、浑浊度、温度等指标,用自动调控装置进行水质净化处理,并将该自控技术和人工检测与净化手段作比对。结果表明:计算机远程在线监测能实时了解水质状况,远程集中管理节约人力成本;游泳池水质参数指标超出安全值时,自控装置会自动预警和报警并自动施药和注水,施药精准度较高,安全性能较好;游泳池水质随着温度和人数变化具有较大的差异性,采用人工手段和自控技术监测与净化相结合的方式管理游泳池,安全系数更高。 相似文献
327.
酸雨对水稻、小麦和油菜种子萌发的影响 总被引:24,自引:3,他引:21
采用pH2.0、2.5、3.0、3.5、4.0与5.0模拟酸雨处理水稻、小麦和油菜种子的实验结果表明,3者在pH 2.0时不发芽,在pH 2.5时只有水稻和小麦异状发芽,pH≥3.0时,水稻、小麦和油菜种子的发芽率、发芽势、发芽指数、活力指数都与pH值显著正相关,水稻和小麦的异状发芽率则随pH值上升而降低.部分生理指标的实验结果表明,水稻、小麦和油菜的吸水值、呼吸速率和贮藏物质运转效率也与pH值显著正相关,水稻与小麦贮藏物质消耗率与pH值显著正相关,而油菜与pH值显著负相关;水稻、小麦和油菜的芽、根长抑制指数都与pH值显著负相关.酸雨胁迫下,种子各项指标变幅为水稻<小麦<油菜,这表明抗酸雨胁迫能力为水稻>小麦>油菜. 相似文献
328.
大豆种皮过氧化物酶在酚类废水处理中的应用 总被引:1,自引:0,他引:1
介绍了大豆种皮过氧化物酶(SBP)的特性、除酚原理及用SBP处理酚类废水的研究进展,对SBP除酚的主要技术参数进行了详细阐述,并对现存问题和解决途径进行了探讨。SBP的性质优异、酶源丰富、价格低廉。直接用大豆种皮处理废水的经济指标已基本达到实用水平,但导致废水中可溶性固形物的含量增加,解决的途径是选育酶活性高、稳定性好的大豆品种。 相似文献
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The free distribution of seeds and tools is the standard approach to agricultural recovery. The predominance of this approach is partly attributable to the: (1) perception that farmer seed quality is poor, (2) insistence on seed certification, (3) promotion of researcher varieties, (4) misdiagnosis of unavailability, (5) difficulty accessing farmer seed, and (6) support for the commercial seed sector. This paper presents a Seed Security Assessment Framework to distinguish among the causes of seed insecurity and focuses on three principal concepts: seed availability; access to seed; and factors associated with seed utilisation. Using this diagnostic framework, Catholic Relief Services (CRS) has developed a better approach to promoting seed system-based agricultural recovery. It involves a combination of seed voucher distribution and the organization of seed fairs, which bring together a range of sellers from whom the holders of vouchers may purchase seed. This approach is advantageous because it: strengthens farmer seed procurement systems; is cost efficient; in economic terms, has a multiplier effect in the community; is straightforward to plan and implement; allows commercial sector participation; provides an opportunity to promote improved varieties for farmer evaluation; brings together different communities. 相似文献