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双语推荐：流失系数

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结合重庆市农业生产的实际情况，在全市设置监测点12个，以一个种植季为监测周期，采集每次降雨后产生的径流和淋溶水，测定其产生量和氮、磷浓度，测算出氮磷流失系数。结果表明，氮主要以地下淋溶途径流失进入水体，磷主要是以地表径流途径流失进入水体。各监测点总氮流失系数在0．011％-10．82％之间，总磷流失系数在0．013％-0．894％之间。氮的流失以硝态氮为主。最高占总氮流失的61．214％。从地表径流看，氮磷流失系数与地面坡度、施肥量成正相关，坡度越高、施肥量越大，氮磷流失系数就越大。从地下淋溶看，养分流失主要受土壤性质的影响，砂质土壤在灌溉或者降雨后，更容易造成养分的流失。
Considering the actual situation of agricultural production of Chongqing City, 12 monitoring sites were established in the munici-pality, with a planting season as a monitoring cycle. Rainfall runoff and leaching water were collected to determine the yield and nitrogen phosphorus concentration, as well as nitrogen and phosphorus loss coefficient. The results showed that nitrogen entered the water body mainly though underground leaching, and phosphorus was drained predominantly with surface runoff. Total nitrogen loss coefficient was between 0.011%and 10.82%, total phosphorus loss coefficient was between 0.013%and 0.894%. Nitrogen loss was mainly with nitrate nitrogen, ac-counting for 61.214%of the total nitrogen loss. Based on the surface runoff, nitrogen and phosphorus loss coefficient was closely related to the ground slope and fertilizer loading rate. Higher coefficients of nitrogen and phosphorus losses were associated with steeper surface slope, and the heavier fertilizer usage. A

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基于2007年第一次全省农业种植业肥料流失普查数据及实测的32种种植模式的肥料流失系数,分析了不同种植作物结构、种植地块坡度、种植方向影响肥料流失的规律,提出云南省农业种植业肥料流失修正系数选取方法。
The fertilizer loss and the loss efficient obtained from the on -site test of 32 types of planting modes based on the first general survey of pollution sources in Yunnan province in 2007 was applied to rectify the loss effi-cient.The crop structure,the slope of the planting field and the direction of planting were analyzed to disclose the law of fertilizer loss.

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为了计算太湖地区稻麦轮作系统中氮、磷的径流排放量,通过2年的小区径流试验,研究了不同施肥方式和施肥量情况下氮、磷的流失规律及流失系数。结果表明:不同施肥处理2008年度和2009年度的全氮流失量分别为14.20~65.17 kg/hm2和38.08~77.76 kg/hm2,流失系数分别为6.02%~9.67%和3.00%~5.16%,麦季氮素的流失以硝态氮为主,而稻季则以铵态氮为主。不同施肥处理2008年度和2009年度全磷流失量分别为0.65~1.21 kg/hm2和0.72~1.15 kg/hm2,流失系数分别为-0.34%~0.19%和-0.81%~-0.15%,但不同施肥处理对径流水中总磷浓度的影响不大。施肥量、降雨时间和降雨量是影响氮、磷流失的主要因素,并且肥料深施、秸秆覆盖、节水灌溉等可在一定程度上降低氮的径流损失。
In order to measure the runoff losses of nitrogen and phosphorus in rice-wheat rotation system, a continu-ous two-year field plot experiment was carried out in Taihu Lake basin under different fertilization amounts and modes. The total nitrogen (TN) losses in 2008 and 2009 were 14. 20-65. 17 kg/hm2 and 38. 08-77. 76 kg/hm2 respectively, and the loss coefficients were 6. 02%-9. 67% and 3. 00%-5. 16%, respectively. The total nitrogen loss was in NH+4-N state main-ly in the rice season, whereas in the wheat season it was in NO-3-N state. The total amounts of nitrogen runoff were signifi-cantly different between years. The total phosphorus (TP) losses in 2008 and 2009 were 0. 65-1. 21 kg/hm2 and 0. 72-1. 15 kg/hm2 respectively, and the loss coefficients were -0. 34%-0. 19% and -0. 81%--0. 15%. TP concentration in runoff was independent of fertilization amounts and modes. Fertilizer input amount, rainfall time and rainfall amount were the main factors that influence the losses of nitrogen a

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根据潜坝壅堵模式的特点,基于异重流理论,给出了泥石流龙头在清水中的运动方程,并提出了有坎宽顶模型的潜坝壅堵上游水位计算式。基于水沙动力过程,以泥石流在坡度变化沟道内的运动方程为基础,考虑堰塞坝和主河水流的相互作用,给出了泥石流在主河中运移距离的计算公式;鉴于泥石流堵塞大河过程中物质流失严重的现象,根据水槽实验数据确定了流失系数;以周必凡提出的泥石流堵断主河总量的计算公式为基础,提出了按流失系数加以修正的泥石流阻塞大河物质总量条件。从而建立了基于动力学方程、物质总量的泥石流阻塞大河综合判据。
According to the characters of the submerged disk and the density current,the runout equations of the debris flow in the water is obtained, and the equation of the head-water level is given by the broad-crested weir theory. Based on the dynamic equation of the debris flow at different slopes,water and sediment dynamic processes, and the interaction between barriers dam of debris flow and main river were considered,and a model of the runout distance of debris flow in big river was established. In view of the phenomenon that the material erosion is very serious when debris flowing into big river,the erosion coeffi?cient is obtaineding using the test dates of flume experiment. Based on the total amount equation of debris flow was blocking given by Bifan ZHOU, a modal of the total amount of the big river blocked by debris flow was considered in hight of the erosion coefficient. The criterion of debris flow blocking big river was presented in terms of dynamic process and total amount of deb

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针对传统的关系型数据管理技术在电信企业面对海量数据对客户流失进行分析研究时存在的海量存储能力和计算能力不足的问题,提出了一种基于MapReduce架构的并行决策树算法,该算法采用校正系数来避免ID3算法多值偏向问题,并应用于客户流失分析中。在Hadoop集群平台上的结果分析表明:基于MapReduce并行模型能够解决电信企业进行客户流失分析时处理大规模数据的问题,在保证分类准确率的情况下能获得趋近线性的加速比,并具有较好的扩展性。
Traditional relational data management technology can not store and process massive datasets when it face analysis of customer churn.To solve this problem,the paper analyzes the parallel algorithm of ID 3 decision tree based on MapReduce model. This algorithm adopted correction coefficient to avoid the multi-value bias problem of ID 3 algorithm.According to the results on the Hadoop cluster,the decision tree algorithm based on MapReduce can deal with massive data classification when telecom-munications company analyzes the churn of the customers.And the algorithm can get close to linear speedup rate and have a good expansibility while ensuring the classification accuracy.

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以黔中黄壤坡耕地氮磷流失长期定位监测基地为平台,于2008—2012年连续5 a进行观测,研究玉米-油菜种植模式下,6种管理措施对黄壤坡耕地地表径流、径流氮输出的控制效果。结果表明:黄壤坡耕地产流系数为15.1%~20.1%,平均18.1%;氮肥流失系数为0.81%~1.34%,平均0.99%;径流氮输出以颗粒态氮所占TN比例46.9%最高,可溶性总氮流失以硝态氮为主,占TN流失的31.1%。优化施肥+横坡垄作+秸秆覆盖+等高植物篱的耕作管理措施截流效果、氮输出控制效果最佳,产流量较CK减少25%;氮肥流失系数最小,为0.81%;TN平均输出总量最小,为4.63kg·hm-2。顺坡常规耕作条件下,优化施肥与常规施肥径流量相当,TN输出量减少23.2%;优化施肥条件下,横坡垄作较顺坡常规耕作径流量减少6.7%,TN输出量减少7.3%;优化施肥+横坡垄作条件下,秸秆覆盖较无秸秆覆盖径流量减少4.8%,TN输出量减少3.4%;秸秆覆盖+等高植物篱较秸秆覆盖径流量减少11.6%,TN输出量减少6.8%。横坡垄作、优化施肥、秸秆覆盖、等高植物篱是控制黄壤坡耕地地表径流、径流中氮输出的有效措施。
Runoff losses of nutrients from soils have aggravated water environmental pollution. A long-term experiment with maize-rape ro-tation was conducted on sloping farming land of yellow soil in Central Guizhou Province from 2008 to 2012. The effects of six management practices on runoff and nitrogen runoff losses were examined. The average runoff coefficient was 18.1% with a range of 15.1%~20.1%. The coefficient of total nitrogen losses ranged from 0.81%~1.34%, with an average of 0.99%. The percentage of particulate N of total nitrogen losses from runoff was the highest(46.9%). Nitrate-N was the dominate form of total dissolved nitrogen with a 31.1% of total nitrogen loss. The best management practice(optimized fertilization+contour cultivation+straw mulch+contour hedgerow)could reduce total nitrogen loss-es effectively, resulting in 25% less runoff than CK. The total nitrogen runoff losses(4.63 kg·hm-2)and loss coefficient(0.81%)were both the lowest under this practice. Under c

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水土流失既是一种非点源污染形式，同时又是其他非点源污染物流失的载体。本文以大亚湾流域为例，利用数字高程模型（ DEM）获取基础资料，通过类比国内外的相关研究成果而获得的输出系数模型参数，采用输出系数模型法估算水土流失型非点源污染负荷，探讨快速评估大尺度水土流失型非点源污染负荷的方法。
Soil erosion is not only the non -point pollution form but also the carrier of other non -point pollutant los-ses.Taking the Daya Bay watershed as the example , the basic materials were gained by using the Digital Elevation Model( DEM) .Based on the analogy of the related research findings at home and abroad , it was discussed the rapid appraisal method to the large scale soil erosion type non -point pollution load to get of the parameters of export coeffi-cient model for the estimation of the soil erosion type non -point pollution load .

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针对重金属铬(Cr)污染严重的现象，基于简单的二层非完全混合模型，将降雨时农田土壤与积水整个系统分为混合区及混合区以下两个部分，根据水量平衡原理和溶质质量守恒定律，研究土壤在非线性Langmuir吸附条件下，吸附性溶质 Cr(VI)的径流流失规律。试验模拟的田间地表径流是由降雨引起的，根据降雨期间土壤与雨水相互作用情况，将降雨过程分为4个阶段分别求解进行研究。利用室内模拟降雨-径流试验所得数据进行模拟计算，并通过敏感性分析和模型参数对径流流失量的影响分析，阐明模型参数对土壤中吸附性溶质径流流失规律的影响。研究结果表明：此二层非完全混合模型能预测土壤在非线性Langmuir吸附条件下，吸附性溶质Cr(VI)的径流流失规律。该模型对入渗水溶质与土壤混合层溶质之间的非完全混合系数γ非常敏感，对土壤混合层溶质与地表积水-径流水溶质之间的非完全混合系数α不敏感，对Langmuir吸附方程中的参数B、C也不敏感。其中γ和α对模拟径流流失过程的影响主要作用于降雨前期，而Langmuir吸附方程中的参数B对模拟过程的影响作用于降雨前期，C也主要作用于降雨前期，但对后期的影响比其他参数更大。试验数据显示地表径流中溶质含量很低，说明该次试验中混合层溶质进入地表积水-径流层量很少，而模拟α值很小，与实际情况吻合，同时也说明，土壤中流失的污染物重金属Cr(VI)大多存在于地下排水中。
Farmland has become less and less in China, but the heavy metal pollution is very serious recently. So, the study on the loss of adsorptive solute of six-valence chromium, i.e. Cr(VI) from soil to surface runoff becomes very important, which is of great significance to understand the expansion of heavy metal pollution in the field. The problem of chromium pollution has been a very serious and worldwide concern recently. In this paper, based on the water balance and solute mass conservation, a simple two-layer incomplete mixing model is used to study adsorptive solute of Cr(VI) loss from soil into surface runoff with nonlinear Langmuir adsorption. Based on the water infiltration, the rainfall process is divided into four stages. Experimental data under the condition of laboratory simulated rainfall-runoff is used to verify the model with nonlinear Langmuir isotherm adsorption equation. Influences of model parameters on the soil solute loss to surface runoff and model sensitivi

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流域非点源污染的监测十分困难,因此数值模拟是定量研究流域非点源污染的主要方法。本文采用基于地貌特征的分布式流域非点源污染模型GBNP(Geomorphology-Based Nonpoint source Pollution model),模拟了新安江上游流域2001—2010年的径流过程和非点源污染物的迁移过程。模型参数的率定与验证结果显示,月径流的Nash效率系数多在0.8以上,确定性系数R2都大于0.9;渔梁和屯溪两个测站的月泥沙负荷的Nash效率系数在0.7以上,确定性系数在0.9以上;两个测站总氮(TN)和总磷(TP)Nash效率系数都在0.55以上,确定性系数都大于0.8。结果表明,该模型在研究区适用性良好。基于模拟结果,分析了研究区内TN、TP以及土壤侵蚀量的时空分布特征。结果显示,研究区多年平均TN流失量为6 706.92 t/a,TP流失量为828.45 t/a,土壤侵蚀量为166.62万t/a。模拟期内年际变化和年内变化结果显示,在其他条件不变的情况下,非点源污染的产生与降雨量大小密切相关。对各区县氮磷分布特点分析可知,TN的空间分布主要受土地利用类型的影响,TP的空间分布主要受土壤侵蚀量的影响。
It’s very difficult to monitor non-point source pollution in a watershed,thus the numerical simu?lation has become the main method for its quantitative research. In this paper,the authors use GBNP(Geo?morphology-Based Nonpoint source Pollution model)model, which bases on geomorphological features, to simulate the process of runoff and non-point source pollution in the upper basin of the Xin’anjiang catch?ment from the year of 2000 to 2010. Considering the monthly discharge,most of the Nash efficiency coeffi?cients are greater than 0.8 and deterministic coefficient are above 0.9;Nash efficiency coefficient and deter?ministic coefficient of monthly sediment load in Tunxi and Yuliang are above 0.7 and 0.9;as for total nitro?gen (TN) and total phosphorus (TP) in these two gauges, Nash efficiency coefficient is more than 0.55 and deterministic coefficient is greater than 0.8. All of them indicate that the model is suitable in the study area. According to the results, the authors

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沙颍河是淮河流域污染较为严重的河流。为正确分析沙颍河流域的面源污染负荷空间分布情况,在已有研究的基础上,采用改进的输出系数模型中农村生活废水、农田化肥流失、畜禽养殖流失、水土流失污染负荷、城镇地表径流污染模型5个模块,对流域面源污染空间分布进行了模拟和负荷估算。研究结果表明,4类污染物（ COD,TP,TN,NH3-N）负荷量最大的区域为上游,其次为中游；单位面积负荷量最大的区域为中游。根据分析结果,确定沙颍河中游为今后重点污染治理的对象。
The Shaying River is a heavily polluted river in the Huaihe River Basin. In order to correctly analyze the spatial dis-tribution of non-point source pollution load in the Shaying River Basin, according to the existing research results, by using the improved export coefficient model composed of five modules including rural life waste water, farmland fertilizer loss, loss of live-stock and poultry breeding, soil erosion and urban surface runoff pollution load, the spatial distribution of the non-point source pollution load in the basin was simulated and estimated. The results show that the load of four pollutants ( COD, TP, TN, ammo-nia nitrogen) in the upstream is the largest, followed by the midstream and the load per unit area in the midstream is the largest, which shows that the midstream of Shaying River will be the key for watershed pollution management.

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