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The role of inland fisheries in livelihoods, food security and sustainable development is often overshadowed by the higher profile interest in ocean issues. Whilst inland fisheries' catch and contribution to global nutrition, food security and the economy, are less than that of marine fisheries, global‐level comparisons of fish production obscure considerable livelihood impacts in certain countries and sub‐national areas. To highlight these contributions, this paper synthesizes recent data and innovative approaches for assessing such livelihood contributions and their importance in countries with limited access to ocean resources and aquaculture. Inland fisheries are crucial for many socially, economically and nutritionally vulnerable groups of people around the world, but the challenges in monitoring inland fisheries preclude a complete understanding of the magnitude of their contributions. This situation is rapidly improving with increasing recognition of inland fisheries in development discourses, which has also encouraged research to enhance knowledge on the importance of inland fisheries. We review this work, including collated information published in a recent Food and Agriculture Organization report, to provide an up to date characterization of the state of knowledge on the role of inland fisheries. 相似文献
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Morantes César Fernández Yarza Florencia Montes María L. Mercader Roberto C. Curutchet Gustavo Torres Sánchez Rosa M. 《Water, air, and soil pollution》2020,231(1):1-13
Water, Air, & Soil Pollution - The treatment efficiency of Chlorella sorokiniana and Scenedesmus species, immobilized in sodium alginate, was evaluated for removing nitrate from groundwater.... 相似文献
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The influence of the obstetrical condition on canine neonatal pulmonary functional competence 下载免费PDF全文
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- Only 800 years ago, New Zealand became the last major land mass to be settled by humans, leading to environmental degradation and precipitating a decline in indigenous fauna. Such ecological downgrading can alter ecosystem processes and drive down the capacity for remnant ecosystems to withstand the anthropogenic pressures of today.
- In New Zealand, these impacts are chronicled in a concise and remarkably complete archaeological record and are distinguishable from natural changes due to changing climate.
- Estuaries are subject to strong environmental gradients that drive productivity and contain critical habitats for key life‐history phases for marine and terrestrial species. Linking land to sea, they host abundant, accessible human resources and are sensitive to anthropogenic environmental modification.
- Austrovenus stutchburyi is a common filter feeding bivalve in New Zealand estuaries. An important food source for Māori, their shells are abundant in middens. Growth rates of A. stutchburyi are affected by multiple environmental factors, including temperature, salinity, nutrients, and sediment, and are recorded through time as easily measurable annual shell bands. Measuring spatial and temporal variation in growth rate of A. stutchburyi can be used to identify the timing of changes in estuarine conditions.
- Growth bands were measured in archaeological and modern (AD 1300–present) A. stutchburyi shells from six sites around New Zealand with varying occupational histories. There were no increases in growth rate, and rates declined measurably over time at three sites (up to a 50% reduction in growth per year). This decline was greater at estuaries that had experienced greater catchment modification, indicating that sediment loading due to land clearance was a likely driver of this change.
- New Zealand's coastline and marine resources are often perceived as wild and pristine. We propose that fundamental changes have occurred in the functioning of coastal marine ecosystems, which constrain its future.
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Sui Chian Phang Michael Cooperman Abigail J. Lynch E. Ashley Steel Vittoria Elliott Karen J. Murchie Steven J. Cooke Scott Dowd Ian G. Cowx 《水产资源保护:海洋与淡水生态系统》2019,29(7):1039-1051
- The ecosystem services provided by freshwater biodiversity are threatened by development and environmental and climate change in the Anthropocene.
- Here, case studies are described to show that a focus on the shared dependence on freshwater ecosystem functioning can mutually benefit fisheries and conservation agendas in the Anthropocene.
- Meeting the threat to fish biodiversity and fisher livelihood is pertinent in developing regions where there is often a convergence between high biodiversity, high dependency on aquatic biota and rapid economic development (see Kafue River, Logone floodplain, Tonle Sap, and Rio Negro case studies).
- These case studies serve as evidence that biodiversity conservation goals can be achieved by emphasizing a sustainable fisheries agenda with partnerships, shared knowledge and innovation in fisheries management (see Kafue River and Kenai River case studies).
- In all case studies, aquatic biodiversity conservation and fisheries agendas are better served if efforts focused on creating synergies between fishing activities with ecosystem functioning yield long‐term livelihood and food security narratives.
- A unified voice from conservation and fisheries communities has more socio‐economic and political capital to advocate for biodiversity and social interests in freshwater governance decisions.