煤矿兼并重组项目水土流失治理探讨

以山西某煤矿兼并重组项目为例，介绍了煤矿重组项目的基本情况和水土流失现状，分析了项目水土流失类型、侵蚀强度、新增水土流失情况，探讨了水土流失治理分区及水土流失治理的措施体系，并提出水土流失治理建议。     

黄土高原水土流失治理模式的层次结构及其演变

面对黄土高原不同历史时期形成的众多的水土流失治理模式,如何正确认识和客观评价,是长期困扰我国水土流失治理与区域持续发展的重大问题。该文根据黄土高原不同时期水土流失治理模式的构成内涵和任务目标,提出水土流失治理模式具有层次性、阶段性和区域适宜性的特点,并将水土流失治理模式划分为区域协调发展模式、小流域治理与发展模式、特定下垫面治理模式和特定问题治理模式4个层次,在此基础上分析了各个层次模式的适宜性。同时根据60多年来水土流失治理模式的演变,提出了水土流失治理模式的阶段性,明确了黄土高原水土流失主要治理模式及其阶段性规律。     

牛草山风电项目水土流失系统治理的思考

结合牛草山风电项目水土流失系统治理工作实践，根据项目区基本情况和水土流失治理方案编制原则，重点介绍了适合深山区的表土保护和土地整治措施、拦渣工程措施、边坡防护工程措施、截排水措施、林草措施、临时措施等水土流失治理措施体系，总结项目区水土流失治理与生态修复措施布设经验，为相似地区风电项目建设提供参考。     

南方红壤花岗岩矿区水土流失治理对策

近些年来，由于矿山大规模开采，带来的水土流失问题日益突出，治理矿区水土流失，恢复和重建矿区生态，建设绿色矿山，是协调矿业发展和生态保护关系，实现矿业绿色发展的必由之路。为探讨南方红壤花岗岩矿区水土流失治理对策，以德庆县花岗岩矿区为研究对象，通过对矿区水土流失治理状况进行现场调查，查阅相关资料，分析矿区水土保持现状及存在的水土流失问题，提出花岗岩矿区水土流失治理需完善水土流失防治措施体系，落实各项水土保持措施，科学合理选择植被恢复物种种类和加强水土保持监测的对策及举措，以期为南方红壤花岗岩矿区水土流失治理及生态保护修复提供参考依据。     

平昌县小流域治理模式及成效

我县自１９８５年成立水土保持机构，１９８９年被列为长治重点县以来，水土流失综合治理的成就辉煌。水土保持工作的总思路是：遵循“因害设防”的原则，分析“害”所产生的根源，对症下药，标本兼治，重在治本，不仅从客观上进行水土流失治理，而且对水土流失区群众的意...     

园林化公墓区水土流失治理模式探讨

园林化公幕产业在我国极具市场潜力，但是在其建设过程中可能引发新的水土流失，如果不进行治理，对公墓区本身和区域环境将造成严重影响。文章以仙居园为例，针对可能发生的水土流失问题，提出相应的治理措施。     

江西省水土流失治理历程及成效

回顾了江西省水土流失治理历程及水土流失治理模式的发展演变,并基于第一次全国水利普查江西省水土保持情况普查成果,结合历史上水土流失调查及普查数据分析了江西省水土流失的变化趋势,阐述了江西省几十年来的水土流失治理成效,为今后江西省水土流失治理和水土保持生态建设工作更好地开展提供了重要参考,有利于江西省生态文明先行示范区建设的加速推进。     

藏东典型小流域水土流失治理模式研究

水土流失是制约藏东山区农牧业发展的主要因素,高山高寒区的水土流失治理模式研究不仅能够解决生活生产的实际需求,也能够丰富水土流失科学研究。以野外调查藏东地区典型小流域的主要水土流失特征入手,结合遥感分析当地土地利用,土壤和植被特征,提出了适用于研究区的5种治理模式:草地冲沟侵蚀区治理模式,水蚀和冻融交错侵蚀区治理模式,坡耕地面状侵蚀区治理模式,沟道侵蚀区治理模式,林—灌—耕地交错区综合治理模式。     

低山丘陵区沟壑三维梯级治理开发模式研究

朝阳市水土流失面积 1195 1 4km2 ,占全市总面积的 60 67% ,沟壑侵蚀面积占水土流失面积的 2 2 40 %。利用沟壑纵剖面信息熵分析法 ,进行沟壑侵蚀地貌形态计量分析 ,按照沟壑三维特征值变化规律 ,将沟壑侵蚀概化为前期、中期、后期三个阶段。采取典型沟壑治理开发试验与大面积沟壑治理开发应用相结合的研究方法 ,建立沟壑三维梯级治理开发措施体系 ,取得了显著的生态、经济和社会效益。     

长江流域水土流失生态化治理模式探讨

长江流域中上游的水土流失十分严重,已严重威胁到全流域的社会、生态、经济的可持续发展。虽然“长治”、“天保”、“退耕”三大工程的实施在一定程度上遏制了水土流失的加剧,但其本身仍有许多局限与不足。由于治理长江流域水土流失十分重要和紧迫,本文在详细分析的基础上提出了开征生态税、发展生态经济农业、实施生态移民、加大生态进口和发展生态旅游等一系列长江流域水土流失生态化治理的新模式。     

Stability of an upland gravel-bed stream, Swinhope Burn, Northern England

Some upland gravel-bed streams often undergo frequent channel change in response to floods and changes in sediment supply. However, in others, where local conditions permit, long-term channel planform stability can be observed. This paper uses evidence from Swinhope Burn in upper Weardale, Northern England, to demonstrate relative channel stability over a 180-year period.Channel planform change is identified using seven historical maps and air photographs dating from 1815 to 1991. The 1.4-km study reach has retained a stable meandering pattern over a period of 180 years, with a temporary but dramatic change to a straight, low sinuosity, partly divided channel, at some point between 1815 and 1856 (identifiable on the 1844 Tithe Map). Channel planform stability, observed over the historic period, is related in part to the low channel gradient upstream of a cross-valley moraine situated at the lower end of the study reach. This moraine has led to partial closure of the valley system and the development of a small upstream floodplain or ‘sedimentation zone’ (average width of 150 m). The resulting low channel gradient (0.012) inhibits coarse bedload transport and encourages overbank sedimentation. Cohesive banks promote lateral channel stability and the wide floodplain reduces potential coupling between the channel and valley-side slope sediment sources.The probable cause of the observed channel planform change is the combination of a succession of four major floods in the River Wear catchment during the 1820s, and episodic inputs of sediment generated by upstream metal mining between 1823 and 1846. Large floods in the past 40 years have produced very little evidence of lasting channel change. However, locally a channel avulsion has been documented following a flood in February 1997. This represents a useful modern analogue for previous mechanisms of channel change.     

LiDAR-derived slopes for headwater channel network analysis

Slope is one of the most important distinguishing features for channel morphology. Variations in the computation of slope from a digital elevation model can affect a wide range of hydrogeomorphically derived applications. We compare different methods for computing channel slope using LiDAR-derived digital terrain models (DTMs) with varying resolutions. We chose a headwater basin of the Eastern Italian Alps, characterized by a dense ephemeral colluvial network and a main alluvial channel as our study area. The identified alluvial morphologies are characteristic of steep mountain streams, namely, cascades and step pools. Field surveys were carried out along the main channel and in some small tributaries. Results indicate that a single method for slope calculation cannot estimate channel slope at the hydrographic network scale. The differential geometry approach for slope calculation tends to overestimate field-surveyed channel slope values for all the DTM resolutions (1, 2, 5 m). When a trigonometric approach for slope calculation is applied, 2 and 5 m DTM resolutions give more consistent results. Nevertheless, a reliable channel slope can be derived from a DTM with an appropriate resolution by choosing a suitable method only after considering the channel width.     

单流道叶轮水力设计方法的研究

系统论述了单流道叶轮水力设计的新方法，新方法较原方法简单、可靠和实用，尤其便于编制计算机辅助设计软件。在对现有的优秀单流道叶轮水力模型进行归纳总结的基础上，给出了用速度系数法设计轴面图时的各速度系数值。借鉴双流道叶轮水力设计中平面图的设计方法，提出了新的单流道叶轮平面图水力设计方法。介绍和分析了新的流道截面面积变化规律和平面图流道中线方程，同时还给出了编程方法及其设计实例的实验结果。     

黄河上游内蒙古河段塑槽输沙需水量分析

为了解冲积性河流塑槽输沙需水量,合理调配水资源,以内蒙古河段为例,依据挟沙水流能量平衡方程,研究了冲积性河流挟沙水流的能量耗散原理及水流塑槽和输沙能量的分配模式,给出了反应冲积性河流冲淤状态的塑槽输沙需水量计算方法,由平滩流量、河道来沙量和冲淤量三者组成的关系确定塑槽输沙需水量。利用内蒙古河段1960-2013年实测资料,计算得到内蒙古河段塑槽输沙水量,汛期来沙量0.7～1.1亿t,塑造2 000～3 000 m~3/s的中水河槽、淤积水平控制30%以下,需要的汛期塑槽输沙水量为94.6～141.2亿m~3;分析了不同条件下汛期塑槽输沙水量变化规律:来沙量一定,同样的中水河槽规模,控制淤积水平越低,需要的塑槽输沙水量越大;来沙量一定,同样的淤积水平,塑造中水河槽规模越大,需要的塑槽输沙水量越大;控制同样淤积水平,塑造同样中水河槽规模,汛期来沙量越大,需要的塑槽输沙水量越大。内蒙古河段塑槽输沙需水量计算结果和结果变化规律可为黄河上游内蒙古河段水资源配置提供参考。     

不同结构滴灌双向流道灌水器抗堵性能对比试验

该文开展滴灌双向流道抗堵性能研究,以提高灌水器对含沙率较高的地表水源的适应性。试验浑水含沙率为30 g/L,经20次浑水试验,设置3种结构参数不同的双向流道灌水器(1#,2#,3#),并对比迷宫式流道灌水器的水力性能和抗堵性能。结果表明:1#、2#、3#双向流道浑水流量分别为清水流量的77.44%,83.35%,85.43%,而迷宫式流道在12次试验后完全堵塞。双向流道灌水器与迷宫式流道灌水器的水力性能及抗堵性能差异显著,且双向流道的水力性能及抗堵性能均优于迷宫式流道;双向流道水力性能越好,抗堵性能越差;流道形式及结构参数是影响灌水器水力性能及抗堵性能的重要因素。试验结束后,观测流道泥沙沉积情况,发现泥沙沉积程度由前段(进口)到后段(出口)逐渐减少;采用电子显微镜分别获取流道前段、中段和后段沉积泥沙样品扫描图像,利用Image Pro Plus 6.0软件分析沉积泥沙样品的粒径组成,发现沿流道方向,粒径(29)0.03 mm的泥沙颗粒质量分数逐渐减小,粒径(27)0.005 mm的泥沙颗粒质量分数呈先减小后增加的趋势;流道沉积泥沙中粒径(27)0.03 mm的颗粒质量分数占92.23%~97.89%,此粒径范围的泥沙颗粒更易在双向流道内沉积,引起堵塞。     

深松铲叶脉状内通道分支出口流速影响因素分析与试验

针对叶脉状内通道深松铲内部结构的液体流速变化会影响深松铲的自润减阻与改良液层施的效果的问题，该研究采用基于计算流体动力学的仿真分析并结合物理试验，研究了结构参数（内通道孔径、孔间距、孔数）和工作参数（主通道入口流速）对分支出口液体出流速度的影响。首先利用仿真方法开展单因素试验，优选出试验因素的水平范围值，其次开展Box-Behnken试验，以各分支出口液体出流速度最大值为目标值，对叶脉状内通道多分支出口管的结构参数和工作参数进行优化取值，建立各影响因素与分支出口流速之间的二阶回归模型，并对模型进行优化求解，进而得到最优参数组合为：内通道分支出口孔径为6 mm、孔间距为110 mm、孔数为4、主通道入口流速为7 m/s。在此工况下，内通道分支出口平均流速为3.264 m/s。按最优参数组合条件对叶脉状内通道进行设计加工并进行相应的物理试验，试验结果为内通道分支出口平均流速2.971 m/s，与仿真结果的误差为8.97 %。由此，检验了叶脉状内通道结构优化设计的效果，同时为具有自润减阻与改良液层施的深松铲叶脉状内通道结构的优化设计提供一定的理论基础。     

柴油机颗粒捕集器不规则六边形孔道结构压降特性研究

为了提高柴油机颗粒捕集器(diesel particulate filter,DPF)的压降特性和碳烟承载量,该文提出了一种不规则六边形孔道结构,并利用AVL-Fire软件建立其三维模型,针对不同排气流量,排气温度,碳烟负载以及灰分堆积情况对DPF压降特性进行数值分析,并与四边形孔道结构进行对比。结果表明:在不同排气流量条件下,建立的数学模型模拟值与实际试验值相对误差处于2.54%~5.69%之间,计算值和试验值的数值差异较小,变化趋势一致;在同等排气流量和排气温度条件下,不规则六边形孔道结构DPF的压降特性优于四边形孔道结构;不同碳烟加载方式会影响DPF压降特性,递减分布压降最高,递增分布压降最低,且不同分布方式下不规则六边形孔道结构具有更低的压降;灰分在DPF内部以层状方式分布对压降影响较大,以尾端方式分布对压降影响较小;不规则六边形孔道DPF具有更陡峭的碳烟过滤效率曲线和更低的压降曲线,表明其能有效地提高碳烟及灰分承载能力,其中碳烟捕集效率上升时间同比降低34%;不同灰分堆积方式下,不规则六边形孔道结构有更小的DPF压降和更高的碳烟承载量,该文可为优化DPF结构,降低DPF压降,减小DPF再生频率提供参考。     

Thresholds for channel initiation at road drain outlets

Slope–Area relationships have been widely used to identify channel initiation points in the landscape. More recently, the importance of road-related rill and gully erosion has been highlighted. Previous studies indicate that channel initiation at road drain outlets can be predicted from the contributing road area and hillslope gradient at the drain outlet. In this study the validity and usefulness of channel initiation thresholds for road runoff management has been evaluated using field data from three catchments in south-east Australia. None of these catchments show a clear separation between channelised and non-channelised sites based on contributing road area and hillslope gradient. Many drains without channel have similar contributing road area and slope gradients as drain with a channel at the outlet. This demonstrates a relatively large variability within our dataset and limits the identification of a slope–area threshold for these catchments. Logistic regression using road area and slope gradient shows that both variables contribute significantly to channel initiation in the Albert and Tyers River catchments, while for the Sandy Creek catchment only slope gradient is significant at the 0.05 level. Stepwise logistic regression on a wider range of variables shows the significance of cut-batter height in two of the catchments, indicating that flow interception at cut-and-fill roads may be important. Comparison of road-related channel initiation thresholds to previously published topographic thresholds, indicates that channels at road outlets tend to form at relatively small contributing areas and steep slopes. Current forest management guidelines do not consider the risk of channel initiation at road drain outlets in road design and drain spacing. The slope–area thresholds are still considered useful in minimising the risk of gully erosion, especially in forestry areas where it appears most likely that channel initiation occurs during a significant rainfall event immediately following hillslope disturbance or road construction.     

Mechanics of mole drainage channel deterioration

The nature of the soil disturbance caused by standard mole ploughs is described and the major types of failure mechanism causing channel deterioration are identified. Direct links have been established between the kinds of mole plough disturbance and many of the channel failure mechanisms, opening up possibilities for the future for modifying the implement to improve channel stability.
Following mole channel observations on six different clay soil sites, the influence of soil conditions at channel installation and subsequent weather patterns on long-term channel stability were determined. The extent of the ageing period between channel formation and its first significant wetting and weather extremes later, were identified as being particularly important influences on the subsequent life of the channel.     

Relationship between suspended sediment load, channel geometry and land area increment in the Yellow River Delta

The annual river discharges and suspended sediment loads into the Yellow River Delta show a declining tendency with some distinct fluctuations over the last 50 years. The decrease of river discharge and suspended sediment load and the change in the river channel must influence the evolution of the Yellow River Delta. During this period several new river mouths formed via channel switch at the river delta, and the old watercourse was gradually abandoned. Recently, in years with very low annual suspended load, erosion of land area has been recorded for the delta. The aims of this work are (1) to determine what is the critical suspended sediment load needed in order to maintain the land balance of the Yellow River Delta for two periods before and after 1976 (the last time the channel shifted), and (2) to examine the variation in the channel geometry and gradient in response to changes in suspended sediment load and delta area at the river mouth. In order to estimate these critical values, we used statistical method to analyze the relationships between land area increment, and suspended sediment load and channel geometry. In order to examine the variation in the channel geometry, the channel cross-sections of the Q1 and Q6 were compared. The results show that to maintain the land area balance between 1953 and 1973, when the river mouth was the Diaokouhe, the critical annual suspended sediment load entering the delta was 4.21  10⁸ tonnes/a. After the main channel switched to Qingshuigou in 1976, the critical value to maintain the Qingshuigou mouth between 1976 and 1997 was 1.51  10⁸ tonnes/a. To maintain the land area balance for the entire Yellow River Delta between 1976 and 1997 the critical suspended sediment load was 3.18  10⁸ tonnes/a. The annual mean channel thalweg elevation and channel gradient at the river delta increase with increasing land area increment at the Qingshuigou mouth. The critical channel gradient at the channel reach between cross sections Q1 and Q6 is 0.000095. The channel has narrowed during the time period from 1976 to 1997. Also, lateral channel migration has decreased remarkably, resulting in enhanced hydraulic efficiency of the deltaic channel and artificial levees. This channel geometry evolution was influenced by river adjustment and human activities. These results are of importance for the management of the lower Yellow River channel and the delta. Future water diversion or river damming should consider the balance between suspended sediment delivery and delta growth.