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431.
程俊 《中国环境管理干部学院学报》2014,(3):51-53,91
合理施肥可以提高作物产量和品质,降低农业生产成本,增加农民收入,减少环境污染;但是,在我国农业发展过程中,农民施用化肥时存在化肥的过量施用、化肥的错误选用以及化肥施用方法不科学等问题;不合理施肥引发了水污染、大气污染和土壤污染。从农业可持续性发展的角度,提出了根据作物性质选择合适肥料,测定土壤性质,根据土壤性质选择合适的肥料,采取科学的方法施肥等建议。 相似文献
432.
陕西省关中地区农业水价调整研究 总被引:3,自引:0,他引:3
本文通过分析关中地区农业水价现状和问题,认为农业水价低于供水生产成本,从需求价格弹性分析表明,价格对农业用水调节作用大,以此提出了价格杠杆调节关中农业用水的措施。 相似文献
433.
Using soundscapes to detect variable degrees of human influence on tropical forests in Papua New Guinea
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Zuzana Burivalova Michael Towsey Tim Boucher Anthony Truskinger Cosmas Apelis Paul Roe Edward T. Game 《Conservation biology》2018,32(1):205-215
There is global concern about tropical forest degradation, in part, because of the associated loss of biodiversity. Communities and indigenous people play a fundamental role in tropical forest management and are often efficient at preventing forest degradation. However, monitoring changes in biodiversity due to degradation, especially at a scale appropriate to local tropical forest management, is plagued by difficulties, including the need for expert training, inconsistencies across observers, and lack of baseline or reference data. We used a new biodiversity remote‐sensing technology, the recording of soundscapes, to test whether the acoustic saturation of a tropical forest in Papua New Guinea decreases as land‐use intensity by the communities that manage the forest increases. We sampled soundscapes continuously for 24 hours at 34 sites in different land‐use zones of 3 communities. Land‐use zones where forest cover was fully retained had significantly higher soundscape saturation during peak acoustic activity times (i.e., dawn and dusk chorus) compared with land‐use types with fragmented forest cover. We conclude that, in Papua New Guinea, the relatively simple measure of soundscape saturation may provide a cheap, objective, reproducible, and effective tool for monitoring tropical forest deviation from an intact state, particularly if it is used to detect the presence of intact dawn and dusk choruses. 相似文献
434.
Paul R. Elsen Ramnarayan Kalyanaraman Krishnamurthy Ramesh David S. Wilcove 《Conservation biology》2017,31(2):416-426
The impacts of land‐use change on biodiversity in the Himalayas are poorly known, notwithstanding widespread deforestation and agricultural intensification in this highly biodiverse region. Although intact primary forests harbor many Himalayan birds during breeding, a large number of bird species use agricultural lands during winter. We assessed how Himalayan bird species richness, abundance, and composition during winter are affected by forest loss stemming from agriculture and grazing. Bird surveys along 12 elevational transects within primary forest, low‐intensity agriculture, mixed subsistence agriculture, and intensively grazed pastures in winter revealed that bird species richness and abundance were greatest in low‐intensity and mixed agriculture, intermediate in grazed pastures, and lowest in primary forest at both local and landscape scales; over twice as many species and individuals were recorded in low‐intensity agriculture than in primary forest. Bird communities in primary forests were distinct from those in all other land‐use classes, but only 4 species were unique to primary forests. Low‐, medium‐, and high‐intensity agriculture harbored 32 unique species. Of the species observed in primary forest, 80% had equal or greater abundance in low‐intensity agricultural lands, underscoring the value of these lands in retaining diverse community assemblages at high densities in winter. Among disturbed landscapes, bird species richness and abundance declined as land‐use intensity increased, especially in high‐intensity pastures. Our results suggest that agricultural landscapes are important for most Himalayan bird species in winter. But agricultural intensification—especially increased grazing—will likely result in biodiversity losses. Given that forest reserves alone may inadequately conserve Himalayan birds in winter, comprehensive conservation strategies in the region must go beyond protecting intact primary forests and ensure that low‐intensity agricultural lands are not extensively converted to high‐intensity pastures. 相似文献
435.
我国正处于农业快速发展的新时期,需要借鉴发达国家经验,提高农业安全监管能力,促进农业生产安全水平提升。本文对美国、澳大利亚、英国、日本等各国近20年农业产业职业安全健康水平进行分析,从立法、监管范围、监管机制、教育培训等方面梳理其职业安全健康工作,同时剖析其农业安全管理经验和存在的主要问题,以此从法规标准、监管体制、基础建设、教育培训等方面提出优化提升我国农业安全生产工作的意见建议。 相似文献
436.
Beasley Lake is a Conservation Effects Assessment Program (CEAP) watershed in the intensively cultivated Mississippi Delta, USA. Lake sediment quality at three sites was evaluated in 2004 and 2008 for biological impairment and uptake (animal tissue pesticide residues) from 14 pesticides and three metabolites using Hyalella azteca (Saussure). Eleven pesticides and three metabolites were detected in sediment among the three sites in 2004 and all 17 compounds examined were detected among the three sites in 2008, with the herbicide atrazine having the greatest concentrations. Twenty-eight-day H. azteca survival and growth (mg w/w) indicated no survival effects at any site for either year, but growth impairment occurred in H. azteca exposed to sediments in 2004, whereas growth enhancement occurred in H. azteca exposed to sediments at one site in 2008. Pesticides observed in animal tissue pesticide residues occurred more frequently and in greater concentrations in 2004 compared with 2008. Thirteen pesticides were detected in animal tissue pesticide residues in 2004, with chlorpyrifos occurring in the greatest concentrations, and six pesticides were detected in 2008, with p,p′-DDT occurring in the greatest concentrations. H. azteca tissue pesticide residues of seven pesticides, two herbicides, three insecticides, one insecticide metabolite, and p,p′-DDT, were associated with growth. 相似文献
437.
George R. Smith 《国际发展与全球生态学杂志》2013,20(2):82-98
SUMMARY The Rio Earth Summit and publication and distribution of Agenda 21 (UN, 1992) have generated much activity in many nations towards development and implementation of community indicators of sustainable development (SI). In recent years efforts at development and implementation of SI have intensified at regional and urban government levels, although fewer efforts are evident at a rural community level. In response to initial ad hoc efforts, methodologies for SI construction are currently being proposed, tested and refined. Within this evolutionary process, increasing recognition is being given to the critical need for, and importance of, ‘stakeholder’ involvement in SI development and implementation. This paper critically reviews these and related efforts from the perspective of rural communities in Canada. The argument is presented that the process of development and implementation of rural community-level SI can significantly benefit from development and implementation of a methodological approach in support of principles and practices of effective stakeholder involvement. It is further argued that development of SI must be stakeholder-driven, and that a pivotal element in the SI development process is the facilitation of information sharing. The paper concludes with a proposal for an approach to stakeholder participation and information sharing achieved through research, testing and refinement, and integration of these concepts within the process of rural community sustainable indicator development. 相似文献
438.
439.
我国农业政策性保险发展策略研究 总被引:1,自引:0,他引:1
当前我国需要完善农业政策性保险政策体系,加大各项政策的补贴力度,通过完善农业保险法律体系,建立专门管理机构,促进农业政策性保险政策顺利实施,保证农业健康稳定发展。 相似文献
440.