Assessment of impact of intensive livestock cultivation on water environment in mountain and hilly areas of South China

[摘要]选择南方山地丘陵区典型规模畜禽养殖集中地为研究区域, 通过对该研究区域周边地表水及地下水的 调查采样, 分析主要污染物时空变异及污染物形态之间的变化, 并对周边水环境进行初步评价。结果表明: 规模化畜禽养殖区域的浅层地下水和地表水已经受到严重污染; 养殖场的环保处理设施与养殖规模不配套 造成大量污染物进入地表水环境; 生物氧化塘的护堤和塘底未经防渗处理, 造成下游地下水污染; 养殖场排 放的污水经厌氧和好氧生物处理后富含有机质、氨氮、可溶态有机磷, 利于作物吸收和生长, 应尽量循环使 用。指出由于养殖污水变化较大, 为避免二次环境污染, 必须处理达标后结合配方施肥技术按需回用农田。[Abstract]By selecting a typical site of intensive livestock cultivation in a mountain area of South China as the study area, and investigating and sampling surface and groundwater in the study area, the spatial and temporal variat ions of the main pollutants and changes among pollutant forms were analyzed. The environmental effects of intensive livestock cultivation on surrounding water environments were evaluated. The results indicated that the shallow groundwater and surfacewater were heavily contaminated in the intensive livestock cultivation area. Large amounts of the pollutants entered the surface water, due to the fact that the wastewater treatment facility did not match the scale of livestock cult ivation. The lack of liner treatment of the bank and liner of the lagoon resulted in groundwater pollution. The effluent wastewater from the culturing farm after anaerobic and aerobic biologic treatment was full of organic matter, ammonia nitrogen, and dissolved organic phosphorus, which aided the growth of plants and should be recycled. Because of the significant change of the wastewater component, and in order to avoid secondary pollution, the wastewater should be recycled to land combined with precision fertilizer formula technology after treatment to bring it to the standard.福建省重大科技项目(2002H009)；福州大学人才基金项目(XRC-0611

塔里木沙漠公路防护林生态工程的综合生态环境效应

为了探讨重大工程的生态环境效应,从风沙环境、土壤环境、小气候、生物多样性和地下水环境5个方面对塔里木沙漠公路防护林工程的综合生态环境效应进行了研究.结果表明:(1)防护林改变了近地表风沙运动过程,防沙体系内风速、输沙率降低幅度分别达64%~80%和87.45%~99.02%,风沙流结构、沙物质粒度、地表蚀积状况也发生了明显变化;(2)与自然流沙地相比,防护林土壤容重减小,全盐含量、总孔隙度和含水量增大,土壤肥力质量明显提高,其变化基本呈现"先快后慢"的规律;(3)防护林对于小环境改善作用明显,距地面6m范围内,林地不同高度的空气温度普遍低于自然流沙地,而空气湿度则高于自然流沙地,林地土壤温度也低于自然流沙地;(4)随着防护林内生境的变化,土壤微生物种类显著增加,但不同种类微生物的种群分布并不均匀;(5)目前防护林灌溉抽水对地下水位、地下水矿化度的影响不大,水位在厘米级范围波动,矿化度的变化幅度在±1g·L-1左右,且没有明显的变化趋势

Thermal resistance analytical model for thermoelectric component with series-parallel connection

为了选择合适的温差电组件和外部换热器,根据非平衡态热力学理论和牛顿冷却定律,对温差电组件采用串并联连接方式的温差发电系统进行了研究,导出了系统输出功率的热阻解析模型,探讨了温差电组件总数量、并联组件数量、热电模块及其热端和冷端的热阻等对系统性能的影响.结果表明,系统电阻与负载电阻、热电模块热阻与其热端和冷端的热阻之间存在匹配关系,能使系统获得最大的输出功率;随着并联组件数量的增加,最大输出功率和回路电流得到了提高,但系统的输出电压却降低了.研究结果为温差发电系统的合理装配及性能优化提供了理论参考.In order to choose the appropriate thermoelectric components and external heat exchangers,the thermoelectric generation system with series-parallel connection of thermoelectric components was investigated according to the non-equilibrium thermodynamics theory and Newton cooling law,and the thermal resistance analytical model for system output power was derived.In addition,the effect of total number of thermoelectric components,number of components with parallel connection,thermoelectric module as well as thermal resistance at both hot and cold ends of the module on the system performance was discussed.The results show that there is a matching relationship between the system resistance and load resistance.Moreover,the thermal resistance of thermoelectric module and the thermal resistance at both hot and cold ends of the module also exhibit a matching relationship.Therefore the maximum output power can be obtained for the system.With increasing the number of components with parallel connection,the maximum output power and loop current get enhanced,while the output voltage of the system decreases.The present results can provide the theoretical reference for the reasonable assembly and performance optimization of thermoelectric generation system.广东省重大科技专项项目(2008A080302002;2010A080405003);粤港关键领域重点突破项目(佛山专项)(2009Z015

混联式混合动力轿车制动器辅助发动机起动控制

针对混联式混合动力轿车起动过程的顿挫等动力性问题，提出一种新型的利用制动器辅助发动机起动的方案，设计了制动器夹紧力矩控制、转矩协调等控制策略，并进行了仿真分析与试验验证。试验结果显示，发动机起动过程动力性改善明显。结果表明，利用制动器辅助发动机起动的方案合理，所设计的起动过程控制策略可行

塔里木沙漠公路沿线风沙危害形成环境分级与区划

通过系统的野外调查与监测,经过量化处理和分级标准确定,对塔里木沙漠公路沿线的风沙灾害形成环境进行了模糊分级与分区,将沙漠公路沙漠段风沙危害形成环境划分为四级,其中易于形成重灾的路段占沙漠段总长度的37.1%;在分级基础上,以沙漠公路沿线五大地貌单元的差异性为基础,结合沿线风况的差异,将沙漠公路沿线风沙危害形成环境从宏观上分为5个区,其中重灾型风沙危害形成环境区占沙漠段的64.3%。沙漠公路风沙危害形成环境程度等级在空间上表现出重复循环的分布规律,但总体上具有自北而南风沙危害形成环境程度逐渐减轻的趋势