[Objectives]To explore the ecological aquaculture model in ponds in North China,several single techniques were assembled into the same culture system.[Methods]Three ponds were selected,the species and stocking rate we...[Objectives]To explore the ecological aquaculture model in ponds in North China,several single techniques were assembled into the same culture system.[Methods]Three ponds were selected,the species and stocking rate were exactly the same,the water was not changed during the culture period,and the water loss due to evaporation and leakage was recovered.Since the middle of May,the hydrochemical indicators such as ammonia nitrogen,nitrite nitrogen,water temperature,dissolved oxygen and pH were monitored every 10 d.According to the monitoring results of ammonia nitrogen,carbon sources were added to the culture ponds to adjust the ratio of C to N,and carbon sources were added 9 times during the culture period.The stocking rate and yield per unit area were accurately measured at the beginning and end of the experiment,and no less than 30 fishes were randomly sampled to calculate the relevant growth indicators and feed coefficients.[Results]Except that the nonionic ammonia in pond 3#exceeded the standard by 10.3%on July 25,all other hydrochemical indicators met the Fisheries Water Quality Standard,and there was no significant difference in all hydrochemical indicators at the same time(P>0.05).The survival rate in 3 ponds was more than 95.0%,the average body weight of individuals out of the pond had no difference(P>0.05),and the feed coefficient was 1.41-1.43.There was no disease during the culture period,and the water was saved by 46.6%compared with the traditional culture model.[Conclusions]This study can provide a basis for the construction of a new model suitable for ecological aquaculture in ponds in North China.展开更多
Hujiatai Village, Xiong County, Hebei Province was nominated as the experimental unit of new countryside construction by Hebei Province in 2008. In order to make Hujiatai Village become a new countryside model with fr...Hujiatai Village, Xiong County, Hebei Province was nominated as the experimental unit of new countryside construction by Hebei Province in 2008. In order to make Hujiatai Village become a new countryside model with friendly ecological and environmental conditions, local energy resources should be considered. In this study, a mode of 'geothermal energy extraction-heat exchange-space heating-reinjection' was adopted to supply heat to resident houses in Hujiatai Village cooperating with a geothermal development entity based on the abundant geothermal resources, thereby constructing a clean, economic and autarkic new countryside energy system, which avoids utilization of fossil-energy, reduces emission of greenhouse gases and generation of solid coal cinder, protecting air and land environment, improving life quality of the people and building a typical model for Hebei Province and even for the whole country.展开更多
桥梁工程是公路建设碳排放的主要环节,T梁桥作为公路项目标准化制造的重要结构形式,掌握其碳排放特征和规律,有助于公路低碳建设和管理。研究采用排放因子法对23座典型T梁桥进行碳排放测算,划定了公路T梁桥建设边界范围,确定了碳排放测...桥梁工程是公路建设碳排放的主要环节,T梁桥作为公路项目标准化制造的重要结构形式,掌握其碳排放特征和规律,有助于公路低碳建设和管理。研究采用排放因子法对23座典型T梁桥进行碳排放测算,划定了公路T梁桥建设边界范围,确定了碳排放测算功能单位,测算了各工程部位的碳排放强度,开展了参数敏感性分析和相关性分析,并提出了基于桥梁长度的桥梁主要结构碳排放估算模型。通过测算结果可知,公路T梁桥建设碳排放强度为8927.13 t CO_(2)e/(km·lane),变化区间为4002.64~9871.74 t CO_(2)e/(km·lane),其中间接碳排放占比为98.28%~99.13%,而直接碳排放为6820.99 t CO_(2)e。桥梁建设约86%碳排放主要集中在预应力T梁和桩基础,碳排放强度分别为1.23 t CO_(2)e/m^(3)、0.68 t CO_(2)e/m^(3);约95%来源于水泥、钢材、回旋钻机和交流电弧焊机。敏感性分析表明,当水泥、钢材、电力、化石燃料碳排放因子变化±(10%~30%)时,碳排放变化分别为±(4.77%~14.32%)、±(4.24%~12.74%)、±(0.57%~1.72%)、±(0.14%~0.43%)。相关性分析表明,桥梁主要工程部位的碳排放受桥梁规模影响较大,可基于桥梁长度快速估算T梁桥整体和各工程部位的碳排放。对此,项目管理者可通过低碳采购等方式降低间接碳排放;可通过优化加工工艺和施工方案等方式,在工程活动中节约材料、降低能耗;可通过降低用量和碳排放因子多种组合方式,对主要材料和能源进行综合减碳。相关结果可为公路建设项目的低碳管理及相关研究提供详实的数据支持和节能降碳措施建议。展开更多
基金the National Modern Agricultural Industry Technology System(CARS-45)Innovative and Entrepreneurship Talent Funding Project of Jilin Provincial Department of Human Resources and Social Security(2021Y011).
文摘[Objectives]To explore the ecological aquaculture model in ponds in North China,several single techniques were assembled into the same culture system.[Methods]Three ponds were selected,the species and stocking rate were exactly the same,the water was not changed during the culture period,and the water loss due to evaporation and leakage was recovered.Since the middle of May,the hydrochemical indicators such as ammonia nitrogen,nitrite nitrogen,water temperature,dissolved oxygen and pH were monitored every 10 d.According to the monitoring results of ammonia nitrogen,carbon sources were added to the culture ponds to adjust the ratio of C to N,and carbon sources were added 9 times during the culture period.The stocking rate and yield per unit area were accurately measured at the beginning and end of the experiment,and no less than 30 fishes were randomly sampled to calculate the relevant growth indicators and feed coefficients.[Results]Except that the nonionic ammonia in pond 3#exceeded the standard by 10.3%on July 25,all other hydrochemical indicators met the Fisheries Water Quality Standard,and there was no significant difference in all hydrochemical indicators at the same time(P>0.05).The survival rate in 3 ponds was more than 95.0%,the average body weight of individuals out of the pond had no difference(P>0.05),and the feed coefficient was 1.41-1.43.There was no disease during the culture period,and the water was saved by 46.6%compared with the traditional culture model.[Conclusions]This study can provide a basis for the construction of a new model suitable for ecological aquaculture in ponds in North China.
基金Supported by the Major Program of Water Resources Exploration in Beijing City(Exploration and Assessment Project of Karst Water Resources in Beijing City
文摘Hujiatai Village, Xiong County, Hebei Province was nominated as the experimental unit of new countryside construction by Hebei Province in 2008. In order to make Hujiatai Village become a new countryside model with friendly ecological and environmental conditions, local energy resources should be considered. In this study, a mode of 'geothermal energy extraction-heat exchange-space heating-reinjection' was adopted to supply heat to resident houses in Hujiatai Village cooperating with a geothermal development entity based on the abundant geothermal resources, thereby constructing a clean, economic and autarkic new countryside energy system, which avoids utilization of fossil-energy, reduces emission of greenhouse gases and generation of solid coal cinder, protecting air and land environment, improving life quality of the people and building a typical model for Hebei Province and even for the whole country.
文摘桥梁工程是公路建设碳排放的主要环节,T梁桥作为公路项目标准化制造的重要结构形式,掌握其碳排放特征和规律,有助于公路低碳建设和管理。研究采用排放因子法对23座典型T梁桥进行碳排放测算,划定了公路T梁桥建设边界范围,确定了碳排放测算功能单位,测算了各工程部位的碳排放强度,开展了参数敏感性分析和相关性分析,并提出了基于桥梁长度的桥梁主要结构碳排放估算模型。通过测算结果可知,公路T梁桥建设碳排放强度为8927.13 t CO_(2)e/(km·lane),变化区间为4002.64~9871.74 t CO_(2)e/(km·lane),其中间接碳排放占比为98.28%~99.13%,而直接碳排放为6820.99 t CO_(2)e。桥梁建设约86%碳排放主要集中在预应力T梁和桩基础,碳排放强度分别为1.23 t CO_(2)e/m^(3)、0.68 t CO_(2)e/m^(3);约95%来源于水泥、钢材、回旋钻机和交流电弧焊机。敏感性分析表明,当水泥、钢材、电力、化石燃料碳排放因子变化±(10%~30%)时,碳排放变化分别为±(4.77%~14.32%)、±(4.24%~12.74%)、±(0.57%~1.72%)、±(0.14%~0.43%)。相关性分析表明,桥梁主要工程部位的碳排放受桥梁规模影响较大,可基于桥梁长度快速估算T梁桥整体和各工程部位的碳排放。对此,项目管理者可通过低碳采购等方式降低间接碳排放;可通过优化加工工艺和施工方案等方式,在工程活动中节约材料、降低能耗;可通过降低用量和碳排放因子多种组合方式,对主要材料和能源进行综合减碳。相关结果可为公路建设项目的低碳管理及相关研究提供详实的数据支持和节能降碳措施建议。
