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231.
Ted L. Napier 《Journal of the American Water Resources Association》2000,36(4):723-735
ABSTRACT: Data were collected in the fall of 1998 and the winter of 1999 from 1,011 land owner‐operators within three watersheds in the North Central Region of the United States to assess adoption of soil and water protection practices. Farm owner‐operators were asked to indicate how frequently they used 18 different agricultural production practices. Many farmers within the three watersheds had adopted conservation protection practices. However, they also employed production practices that could negate many of the environmental benefits associated with conservation practices in use. Comparison of adoption behaviors used in the three watersheds revealed significant differences among the study groups. Respondents in the Iowa and Ohio watersheds reported greater use of conservation production systems than did farmers in Minnesota. However, there were no significant differences between Ohio and Iowa farmers in terms of use of conservation production practices. This was surprising, since farmers in the Ohio watershed had received massive amounts of public and private investments to motivate them to adopt and to continue using conservation production systems. These findings bring into serious question the use of traditional voluntary conservation programs such as those employed in the Ohio watershed. Study findings suggest that new policy approaches should be considered. It is argued that “whole farm planning” should be a significant component of new agricultural conservation policy. 相似文献
232.
Offshore wind energy development (OWED) is being pursued as a critical component in achieving a low-carbon energy economy. While the potential generating capacity is high, the cumulative effects of expansion of OWED on wildlife remain unclear. Since environmental regulations in many countries require analysis of the cumulative adverse effects (CAE) during permitting processes, this paper reviews the state of knowledge on CAE of OWED on wildlife. We synthesize ecological research on the effects of OWED on wildlife; delineate a framework for determining the scope of CAE assessments; describe approaches to avoiding, minimizing and compensating for CAE; and discuss critical uncertainties. 相似文献
233.
《Journal of Environmental Policy & Planning》2012,14(2):137-147
This paper presents the relationship between an environmental protection scheme, established in Ireland in 1994 under EU Regulation No. 2078/92, and the livelihoods of Irish farm households. It explores this relationship within the framework of the new policy environment for EU agriculture and rural areas as set out in Agenda 2000. At the centre of this new policy environment is the European model for agriculture, embodying the concept of multifunctionality, which recognizes the pivotal position of an evolving agricultural sector in enhancing the viability of rural areas through broadening the assets of farm families. Research undertaken with farm households in the west of Ireland indicates a positive relationship between the Rural Environmental Protection Scheme and the economic and natural assets upon which they build their livelihoods. The case of a small-scale dairy farm household is presented, showing clearly the positive impact of the scheme, while also highlighting the vulnerability of these improvements. A major challenge facing policy-makers is the extent to which acceptable levels of income and an enhanced natural environment on such farms can be sustained. The position of advisory and research institutions in strengthening human capacities on farms is highlighted and their enhanced role is suggested in order to give meaning to multifunctional and sustainable agriculture within the context of rural area viability. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
234.
Sayuri Shimazu Yukiko Kawabata Akito Inayoshi Hideyuki Inui Hitoshi Ashida Hideo Ohkawa 《Journal of environmental science and health. Part. B》2013,48(8):741-749
Four expression plasmids for recombinant human aryl hydrocarbon receptor (hAhR) consisting of a ligand binding domain of hAhR, a DNA-binding domain of LexA and a transactivation domain of VP16 as well as β-glucuronidase (GUS) reporter genes were constructed. All the expression plasmids were transformed into tobacco plants. The selected transgenic tobacco plants were used to assay. PCB congeners showed GUS activity in a TEF-dependent manner. The selected transgenic tobacco plant XhD4V17 was compared with the transgenic tobacco plants XmD4V26 and XgD2V23 containing recombinant mouse (m) AhR-mediated GUS reporter gene expression cassette and recombinant guinea pig (g) AhR-mediated GUS reporter gene expression cassette for PCB congener-inducible GUS activity. The data revealed that the tobacco plant XgD2V23 was the most active in PCB congener-inducible GUS activity. In a 1:1 mixture of PCB126 and PCB80 a reduced PCB126-induced GUS activity was observed in plant XgD2V23, which could possibly be due to interaction between PCB126 and PCB80. 相似文献
235.
236.
Recently, Australian interest in farm dams has focused on rates of harvest of surface waters (runoff), and the impact this has on nearby natural systems. Little research has been directed towards the role of these artificial water bodies in sustaining biological reserves within the wider ecosystem. Macroinvertebrate communities in three farm dams in the Central Tablelands of New South Wales were surveyed, and water quality variables were correlated with species richness and abundance. Community responses to habitat factors including sediment depth, stock use, vegetation and debris were also examined. Communities were described at several taxonomic levels in addition to allocation to trophic groups and primary functional feeding groups.Species richness and abundance of communities were found to vary between dams and between habitat types within dams. The extent of these differences was decreased when communities were described by either trophic status or functional feeding mechanisms. Habitats were influenced by water quality and by physical features of the habitat, with the two factors interacting to define equilibrium conditions. Localised conditions resulted in different macroinvertebrate communities. Physicochemical parameters that correlated most closely with communities included light penetration, chlorophyll-a and conductivity. Habitat factors that were most frequently linked with communities were sediment depth and canopy cover, with localised disturbances related to stock use affecting feeding groups rather than specific taxa.One of the major problems associated with increasing modification of landscapes by agriculture or urbanisation is the fragmentation of undisturbed habitats. Creation of joint aquatic and woodland habitats enhances biodiversity corridors. The recognition of the potential for farm dams as reservoirs of biodiversity and development of management practices that optimise this neglected biodiversity reserve may have much wider benefits biologically, aesthetically and productively. 相似文献
237.
We applied pyrosequencing to determine bacterial communities in soil samples taken from test fields amended by manures of pigs fed with green feeds (GPMS), synthetic feeds (APMS), and the reference field without swine manure amendment (NPMS), respectively. For each sample, 7050 effective sequences were selected and utilized to do the bacterial diversity and abundance analysis, respectively. In total, 2986, 2873, and 1602 operational taxonomic units were obtained at a 3% distance cut-off in GPMS, APMS, and NPMS, respectively. Bacterial phylotype richness in GPMS was higher than the other samples. NPMS had the least richness. The most dominant class in both GPMS and APMS is Betaproteobacteria, whereas Alphaproteobacteria is dominant in NPMS. Circa 7.5% sequences in GPMS were found to be affiliated with Burkholderiales order. Bacterial diversity and abundance in the soil varied with swine manure amendment, due to nutrient elements as well as toxic metals in swine manures. Compared with the soil amendment by manures from pigs bred with synthetic feeds, more bacterial diversity but less potentially pathogenic bacterial genera in the soil amended by manures of pigs fed with green feeds were found, which indicated that these manures were better land-applied organic fertilizers. 相似文献
238.
选取钢丝绳行业比较发达的某乡镇为研究区域,对其地区周边土壤及农产品的污染状况进行了野外调查和实验分析研究。结果表明:(1)土壤中铅、锌的含量均有不同程度的污染。(2)土壤中重金属含量与废水灌溉方式有关。(3)废水灌溉的农产品均有不同程度的污染。(4)重金属主要富集在农产品的根部,果实中富集的量很少。 相似文献
239.
240.
鸡粪与猪粪所含土霉素在土壤中降解的动态变化及原因分析 总被引:3,自引:1,他引:3
采用室内模拟培养实验,研究不同用量鸡粪与猪粪所含土霉素在土壤中降解的动态变化规律及消解途径.结果表明,畜禽粪便中土霉素在土壤中能迅速进入降解期,含量变化呈"L"型,但不同粪肥种类和用量处理的降解率和变化幅度有显著差异(P<0.05).180 d时,鸡粪处理土壤中OTC的降解率高于猪粪处理,半衰期分别为26.98 d和31.32 d.低用量鸡粪和猪粪处理土壤中OTC降解率最大,对应分别可达84.06%和80.47%.降解率与畜禽粪便用量呈负相关,与时间呈正相关且可用v=A+Blnt回归方程拟合(r>0.96).土霉素进入土壤50 d时,光降解量占减少总量的20.03%,下降了25.05%;微生物降解量占3.16%,增加了2.50%.可见,鸡粪所含土霉素在土壤中的降解情况好于猪粪,光照对土壤中土霉素有较好的降解作用,土壤微生物降解作用很小,且随着培养时间的延长,微生物降解增加,光降解减弱. 相似文献