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491.
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
492.
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
493.
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
494.
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
495.
496.
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
497.
498.
针对目前输气站场设备风险评价方法仅以单个设备为评价对象,并未考虑设备间相互影响的特点,提出将多米诺效应分析引入输气站场设备风险评价当中,再结合RBI(基于风险检测方法)对输气站场设备进行定量风险评价。首先,计算所评价设备的失效概率与危险指数,得到设备固有风险;然后对设备的多米诺效应风险进行计算;最后,得到设备总风险。实例分析表明,考虑多米诺效应风险后,站场单个设备的风险要明显增大。 相似文献
499.
国家历史文化名城地区记录了华夏农耕文明更多的生活经验,论文以这些城市地区为研究对象,通过在全国尺度选取典型群体110 个国家历史文化名城地区为样本,并定义农业水文地质适宜度指标,对各类水文地质与农业活动的空间关系进行了量化。从研究结果来看:各富水程度的松散岩类孔隙含水岩组是农业适宜性较强的水文地质类型;碳酸盐岩类含水岩组的农业适宜性也较强;而岩浆岩类含水岩组以及变质岩类含水岩组等则是农业适宜性较弱的水文地质类型,其中松散岩类孔隙含水岩组的农业水文地质适宜度是岩浆岩类含水岩组以及变质岩类含水岩组的2~3 倍。 相似文献
500.
Soil organic carbon (SOC) and soil total nitrogen (STN) concentrations and stocks are essential for improving soil quality and increasing C-reservoir. The study aimed at quantifying the dynamics of soil properties under different land use in Imo watershed where there is no knowledge about the effects of land use on SOC and STN pool. Six land use: arable land (AL), forest land (FL), grassland (GL), shrubland hills (SL), urban built-up green (UL), and freshwater swamp-mangrove wetland (WL) were classified using ArcGIS 10.1 and FAO land use classification system. Soil samples were collected and analyzed from each land use under different soil depths and slope positions with three replications. Topsoil layer (0–30?cm) contributed to more than 90% of the total soil nutrients. Land use significantly affected SOC content, STN content, and bulk density. SOC and STN concentrations were in the order of FL?>?WL?>?GL?>?SL?>?UL?>?AL which revealed the potentials of FL and WL for SOC and STN sequestration. The study provides land users with the information to improve soil quality, conserve C and N stocks for ecological sustainability and climate change mitigation. 相似文献