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301.
张文政 《资源开发与市场》2010,26(5):430-432,435
入境旅游作为山东省旅游业发展的工作重点,其入境客源市场的变化应作为山东省旅游业发展战略制定的重要基础条件进行分析和研究。依据山东省1998—2007年间的入境旅游相关统计数据,通过亲景度分析,探讨山东省入境旅游市场的年际变化、亲景度国别差异及空间演变,在此基础上提出了山东未来拓展入境旅游市场的对策与建议。  相似文献   
302.
以西藏自治区为例,在2009年农户抽样调查数据基础上,利用数据包络法(DEA)探讨西藏不同区域农户生产效率,认为西藏农户生产效率差异与农业生产中自用价值的计算有关,若考虑自用价值,在固定生产规模报酬(CRS)假设下,平均生产效率为0.653,其中拉萨市最高(0.784),日喀则市最低(0.277);若不计入自用价值,山南与那曲地区呈现最高生产效率。表明西藏农户收入中自用价值占了较大比例,扣除自用价值,收入大幅减少,影响生产效率。因此,提高农牧户生产商品率是增加农牧民收入的有效途径。  相似文献   
303.
Fish is a major source of livelihood for the majority of people living around the Okavango Delta in northwestern Botswana. Gender dynamics and governance regimes determine differential access to, and control of, resources between women and men in the area. The purpose of this case study is to critically assess the embeddedness of gendered inequities in the governance of Okavango Delta fishery. Primary data was collected through focus group discussions and face‐to‐face interviews of 96 basket fishers from five villages along the Panhandle area of the Okavango River. The study found that past and present Okavango Delta fishery policy and programme interventions tended to entrench rather than minimize gendered disparities between women and men fishers' access to and control over fish resources, asset accumulation and employment opportunities. Basket fishers have intimate knowledge of flood variability, fish migration and habitat and use this knowledge to make decisions about when and where to harvest what fish species. Women fishers' ecological knowledge, interests and concerns however, have been excluded from current zoning and closed season regulations and co‐management structures. The paper concludes that past and current development interventions as well as the regulatory framework continue to entrench pre‐existing gender relations in the fishery sector which excludes, disempowers and marginalizes women fishers. We recommend innovative co‐management and local based structures which recognize the diversity of interests and interest groups.  相似文献   
304.
土地集约利用评价方法研究综述   总被引:4,自引:0,他引:4  
基于土地利用类型和评价尺度,应用文献资料法和综合分析法,梳理了国内20世纪90年代以来土地集约利用评价研究,阐述了土地集约利用的内涵,着重探讨了各种评价方法针对不同用地类型和不同评价尺度的实践应用,归纳各种评价方法并进行对比分析,探讨未来土地节约集约利用评价方法的研究方向和发展趋势.  相似文献   
305.
规模化畜禽养殖产污系数研究   总被引:1,自引:0,他引:1  
吴艳娟  罗彬  杨媛媛 《资源开发与市场》2012,(12):1096-1098,1101
随着畜禽养殖逐渐走向规模化,畜禽养殖污染已成为农村污染的重要来源。以规模化畜禽养殖产生的废水和固体废弃物为监测对象,对规模化畜禽养殖产污系数进行研究,给出单位畜禽从出生到出栏的产污系数计算方法。以四川省内江市为实例,计算了不同季节、不同规模的规模化养猪场产污系数,并与第一次污染源普查数据进行比较。  相似文献   
306.
Granular activated carbon (GAC) exhaustion rates on pulp and paper effluent from South East Australia were found to be a factor of three higher (3.62 cf. 1.47 kg m−3) on Kraft mills compared to mills using Thermomechanical pulping supplemented by Recycled Fibre (TMP/RCF). Biological waste treatment at both mills resulted in a final effluent COD of 240 mg L−1. The dissolved organic carbon (DOC) was only 1.2 times higher in the Kraft effluent (70 vs. 58 mg L−1), however, GAC treatment of Kraft and TMP/RCF effluent was largely different on the DOC persisted after biological treatment. The molecular mass (636 vs. 534 g mol−1) and aromaticity (5.35 vs. 4.67 L mg−1 m−1) of humic substances (HS) were slightly higher in the Kraft effluent. The HS aromaticity was decreased by a factor of 1.0 L mg−1 m−1 in both Kraft and TMP/RCF effluent. The molecular mass of the Kraft effluent increased by 50 g mol−1 while the molecular mass of the TMP/RCF effluent was essentially unchanged after GAC treatment; the DOC removal efficiency of the GAC on Kraft effluent was biased towards the low molecular weight humic compounds. The rapid adsorption of this fraction, coupled with the slightly higher aromaticity of the humic components resulted in early breakthrough on the Kraft effluent. Fluorescence excitation-emission matrix analysis of the each GAC treated effluent indicated that the refractory components were higher molecular weight humics on the Kraft effluent and protein-like compounds on the TMP/RCF effluent. Although the GAC exhaustion rates are too high for an effective DOC removal option for biologically treated pulp and paper mill effluents, the study indicates that advanced organic characterisation techniques can be used to diagnose GAC performance on complex effluents with comparable bulk DOC and COD loads.  相似文献   
307.
采用静态阻垢试验方法研究了磁场与ESA/AMPS共聚物共同作用时的协同阻垢性能。结果表明,磁场与ESA/AMPS共聚物对碳酸钙和磷酸钙有协同阻垢作用,当磁化水流量为120L/h、磁场强度为0.7T、磁化时间为40min、ESA/AMPS共聚物用量为3mg/L时,ESA/AMPS共聚物与磁场对CaCO3的协同阻垢率比单独使用ESA/AMPS共聚物时提高了12%;在其他条件不变,而ESA/AMPS共聚物用量为14mg/L时,磁场与ESA/AMPS共聚物对Ca3(PO4)2的协同阻垢率比单独使用ESA/AMPS共聚物时提高42.4%。利用扫描电镜(SEM)和x-射线衍射仪(XRD)对CaCO,垢样进行了观察,发现ESA/AMPS共聚物对垢样晶型产生扭曲作用,而磁场与ESA/AMPS共聚物协同作用时的垢样晶型没有太大改变。  相似文献   
308.
利用双通道工业循环冷却水分析测试台和高压静电水处理器,对火电厂的冷却水进行阻垢效果和机理研究。结果表明,施加工作电压2.0~4.0kV时,平均阻垢率随电压的升高而增大,达到61.7%,以后随着电压的升高平均阻垢率呈下降趋势,在7.5kV电压作用下平均阻垢率43.4%。对垢样晶体的SEM扫描图片表明,经高压静电场处理前的水垢晶体以方解石型硬垢为主,处理后发生了晶型转化,转化为文石型软垢,有利于垢的去除。  相似文献   
309.
A novel mixed bacterial culture was enriched from an endosulfan (6, 7, 8, 9, 10, 10 – hexachloro-1, 5, 5a, 6, 9, 9a-hexahydro-6, 9-methano-2, 3, 4-benzo (e) dioxathiepin-3-oxide) processing industrial surface soil. The cultures were successful in the degradation of aqueous phase endosulfan in both aerobic and anaerobic conditions. Using the cultures, endosulfan degradation in silty gravel with sand (GM) was examined via pilot scale reactor at an endosulfan concentration of 0.78 ± 0.01 mg g? 1 of soil, and optimized moisture content of 40 ± 1%. During operation, vertical spatial variability in endosulfan degradation was observed within the reactor. At the end of 56 days, maximum endosulfan degradation efficiency of 78 ± 0.2% and 86.91 ± 0.2% was observed in the top and bottom portion of the reactor, respectively. Both aerobic and anaerobic conditions were observed within the reactor. However, endosulfan degradation was predominant in anaerobic condition and the total protein concentration in the reactor was declined progressively down the soil depth. Throughout the study, no known intermediate metabolites of endosulfan reported by previous researchers were observed.  相似文献   
310.
This study simulated crop and water yields in the Missouri River Basin (MRB; 1,371,000 km2), one of the largest river basins in the United States, using the Soil and Water Assessment Tool (SWAT) at a fine resolution of 12‐digit Hydrological Unit Codes (HUCs) using the regionalization calibration approach. Very few studies have simulated the entire MRB, and those that have developed were at a coarser resolution of 8‐digit HUCs and were minimally calibrated. The MRB was first divided into three subbasins and was further divided into eleven regions. A “head watershed” was selected in each region and was calibrated for crop and water yields. The parameters from the calibrated head watershed were extrapolated to other subwatersheds in the region to complete comprehensive spatial calibration. The simulated crop yields at the head watersheds were in close agreement with observed crop yields. Spatial validation of the aggregated crop yields resulted in reasonable predictions for all crops except dryland corn in a few regions. Simulated and observed water yields in head watersheds and also in the validation locations were in close agreement in naturalized streams and poor agreement in streams with high groundwater‐surface water interactions and/or reservoirs found upstream of the gauges. Overall, the SWAT model was able to reasonably capture the hydrological and crop growth dynamics occurring in the basin despite some limitations.  相似文献   
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