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51.
Over the past several decades, consumers in the global North have increasingly looked to fair or alternative trading systems
as a means to promote ecologically and socially sustainable agricultural production. While fair trade has historically been
limited to international commodity networks, US-based agro-food activists have recently turned their attentions towards building
a domestic movement, to bring fair trade principles and standards ‘home.’ Through an exploration of this growing movement,
we consider the potential for third party certification and labeling to incorporate social justice into US-based agricultural
production, with a particular focus on the implications for farm workers. We view current efforts to bring the principles
of fair trade to the domestic arena as a reflection of several interrelated developments: a growing need on the part of small
and mid-sized farmers to garner price premiums due to the erosion of the organic price premium; a recognition of the failure
of organic certification to advance a holistic vision of sustainability; and the strategic embrace of voluntary regulatory
mechanisms as an alternative to public regulation and collective bargaining. Initial research suggests that this has led to
particular framings of the domestic fair trade concept, which may undermine the movement’s ability to address the social relations
of agro-food production. Specifically, prioritization of the ‘family-scale’ farm and an undercurrent of food localism may
obscure farm workers’ role in valorizing the US agricultural landscape.
相似文献
Christy GetzEmail: |
52.
53.
Postglacial vegetation, fire, and climate history of the Siskiyou Mountains, Oregon, USA 总被引:1,自引:0,他引:1
The forests of the Siskiyou Mountains are among the most diverse in North America, yet the long-term relationship among climate, diversity, and natural disturbance is not well known. Pollen, plant macrofossils, and high-resolution charcoal data from Bolan Lake, Oregon, were analyzed to reconstruct a 17,000-yr-long environmental history of high-elevation forests in the region. In the late-glacial period, the presence of a subalpine parkland of Artemisia, Poaceae, Pinus, and Tsuga with infrequent fires suggests cool dry conditions. After 14,500 cal yr B.P., a closed forest of Abies, Pseudotsuga, Tsuga, and Alnus rubra with more frequent fires developed which indicates more mesic conditions than before. An open woodland of Pinus, Quercus, and Cupressaceae, with higher fire activity than before, characterized the early Holocene and implies warmer and drier conditions than at present. In the late Holocene, Abies and Picea were more prevalent in the forest, suggesting a return to cool wet conditions, although fire-episode frequency remained relatively high. The modern forest of Abies and Pseudotsuga and the present-day fire regime developed ca. 2100 cal yr B.P. and indicates that conditions had become slightly drier than before. Sub-millennial-scale fluctuations in vegetation and fire activity suggest climatic variations during the Younger Dryas interval and within the early Holocene period. The timing of vegetation changes in the Bolan Lake record is similar to that of other sites in the Pacific Northwest and Klamath region, and indicates that local vegetation communities were responding to regional-scale climate changes. The record implies that climate-driven millennial- to centennial-scale vegetation and fire change should be considered when explaining the high floristic diversity observed at present in the Siskiyou Mountains. 相似文献
54.
Northern pipefish,Syngnathus fuscus, and dusky pipefish,Syngnathus floridae, are among the most abundant ichthyofauna components of the Chesapeake Bay, USA, eelgrass beds,Zostera marina, but population structure and many life history traits remain uncharacterized. We conducted monthly collections from May
through September 2003–2005 in Chincoteague Bay, Virginia, to investigate seasonal migration and spawning, sex ratios, size
at maturity, sexual dimorphism in length, and growth rates. BothS. fuscus andS. floridae spawned from May through September. Water temperature was significantly correlated withS. fuscus catches, whereasS. floridae abundance peaked after maximum water temperatures. Sex ratio data indicatedS. floridae populations are balanced, whileS. fuscus populations are strongly female-biased. Both species can quickly reach reproductive maturity, potentially within one season,
becauseS. fuscus andS. floridae population growth rates average 1.0 mm d−1 and minimum standard length at maturity measures 125 and 103 mm, respectively, for females and 99 and 91 mm, respectively,
for males. ForS. fuscus, females were significantly longer than conspecific males during time periods when juveniles were not rapidly maturing. Size
sexual dimorphism in this species coincides with reports of extensive paternal care and supports the hypothesis that the strength
of sexual selection differs in these species. 相似文献
55.
Depth-dependent sampling to identify short-circuit pathways to public-supply wells in multiple aquifer settings in the United States 总被引:3,自引:2,他引:1
Matthew K. Landon Bryant C. Jurgens Brian G. Katz Sandra M. Eberts Karen R. Burow Christy A. Crandall 《Hydrogeology Journal》2010,18(3):577-593
Depth-dependent water-quality and borehole flow data were used to determine where and how contamination enters public-supply wells (PSWs) at study sites in different principal aquifers of the United States. At each of three study sites, depth-dependent samples and wellbore flow data were collected from multiple depths in selected PSWs under pumping conditions. The chemistry of these depth-dependent samples, along with samples of the surface discharge from the PSWs, was compared to that of adjacent nested monitoring wells. The results of depth-dependent analyses from sites in Modesto (California), York (Nebraska), and Tampa (Florida) are summarized and compared. Although the exact mechanisms for transport of contaminants to the PSWs varied among these hydrogeologic settings, in all three settings the presence of wells or boreholes or natural preferential flow paths allowed water and contaminants to bypass substantial portions of the aquifer and to reach PSWs or depths in the aquifer more quickly than would have occurred in the absence of these short-circuiting flow paths. The chemistry and flow data from multiple depths was essential to developing an understanding of the dominant flow paths of contaminants to PSW in all three settings. This knowledge contributes to developing effective strategies for monitoring and protection. 相似文献