海委布置2013年度海河流域全国水土流失动态监测与公告项目

2013年3月9—10日,海河流域水土保持监测中心站在天津市布置了2013年度海河流域全国水土流失动态监测与公告项目。
　　会议介绍了2013年度全国水土流失动态监测与公告项目中海河流域的主要工作任务,明确了海河流域要对国家级水土流失重点治理区(永定河重点治理区、太行山重点治理区)、国家级水土流失重点预防区(滦河重点预防保护区)、不同土壤侵蚀类型区(5个典型小流域、8个典型监测点)的水土流失情况进行监测,对流域监测网络和信息系统进行运行维护,为年度中国水土保持公报编制提供海河流域水土流失监测数据。     

九龙江流域水土保持生态环境分析

通过对九龙江流域水土保持生态环境进行调查和综合分析,确定了该流域水土流失的现状和主要问题,并根据流域的水土流失特点和流域情况,划分了流域的水土流失类型区,在此基础上进一步对流域的水土流失治理进行布局,并结合区域经济发展的需求,提出“三片一带”的防治分区和具体治理措施。     

小塔山水库流域水土保持与河流泥沙特性分析

为了了解淮河流域近年来水土流失的特点,分析造成水土流失的主导因素,本文采用黑林水文站12年的降水、径流及泥沙资料,根据流域水土保持与河流泥沙分布情况相关性,通过分析降水量与径流量及径流量与含沙量之间的相互关系,总结了流域水土流失特点及造成水土流失的主要原因,结果表明近年来生产建设活动等人为因素是造成流域内水土流失的主要因素,以期为流域今后水土保持工作重点提供参考依据。     

澜沧江流域水土流失及防治对策

该文根据大量的水文及监测数据，分析了澜池江流域水土流失的现状及水土流失的原因，得出以下结论：（１）澜沧江流域水土流失从总体上看较轻，但局部地区较严重；（２）澜沧江流域局部地区水土流失呈发展趋势，其主要原因，是人为破坏，根据上述结论、提出了防治水土流失的对策。     

潮河流域水土流失治理成效及存在问题分析

以占密云水库以上集水流域面积31%的潮河流域作为研究区域.在对流域水土保持和水土流失状况进行分析的基础上,阐明了流域水土保持工作在减轻水土流失,改善生态环境,提高社会经济效益方面的作用.阐述了流域水土流失治理中存在的一些问题,拟为流域综合治理提供政策启示.     

基于水文模型的辽西地区水土流失模拟研究

将改进的通用土壤侵蚀方程与水文模型耦合,构建基于新安江模型的水土流失模拟模型,以辽西大凌河大城子水文站以上流域为研究区域,基于大城子水文站2001-2010年水文数据,定量模拟了研究流域的水土流失。研究结果表明:构建的水土流失模型可较好地模拟大凌河流域的水土流失,其中水量模拟相对误差小于10%,确定性系数达到0.8以上,水土流失模拟的相对误差小于20%,确定性系数达到0.5以上,模型在辽西大凌河流域具有较好的适用性。研究成果可以为辽西大凌河流域水土流失模拟和水土资源保护提供参考。     

南昆铁路威红区段段家河流域地貌演化与水土流失

在对段家河流域多次实地考察的基础上，通过对该流域的地貌特征分析，认为目前段家河流域地貌演化正处于壮年期，是水土流失，滑坡，泥石流的发育和活动的旺盛期；该流域的水土流失比较严重，地表土层的平均侵蚀模数为２６００ｔ（ｋｍ＾２·ａ）。根据流域各段水土流失的程度不同，对流域水土流失进行了分区。然后，进一步探讨了水土流失与流域地貌演化的关系。     

汀江流域水土流失现状及特点分析

汀江流域以其水土流失面积大、强度以上流失比重大和崩岗点多面广而成为福建省水土流失最严重的区域。水土流失分布相对集中是汀江流域水土流失的又一特点，95．56％的流失集中于林地；52．86％的流失集中在长汀。建议通过调整产业结构，改变农民的生产生活方式来解决该流域的水土流失问题。     

福建省木兰溪流域水土流失特点及防治对策

简要介绍木兰溪流域的基本情况和水土流失现状,指出流域的水土流失具有上游地区流失面积大、下游地区流失级别强、水源地面源污染严重的特点。分析其产生的原因,根据不同的水土流失特点,将流域划分成三个类型区,针对各分区存在的问题,提出相应的防治对策。     

广西江村小流域水土保持工程治理成效

开展小流域水土保持综合治理对防治广西岩溶区水土流失问题十分必要。通过对江村小流域进行水土保持综合治理成效监测,分析该区域治理后水土流失面积消长情况,总结小流域治理成效。结果表明,治理后的江村小流域水土流失状况朝着积极的方向发展,2020年水土流失面积较2016年减少了462.77 hm~2,土壤侵蚀强度降低了25.66 t/(km~2·a),江村小流域的水土流失面积和强度得到了有效控制,水土流失治理初见成效。     

不同农作措施红壤坡耕地水土流失特征的研究

研究了 6种不同农作措施下红壤坡耕地水土流失特征 ,结果表明 :同顺坡农作措施相比 ,其它农作措施均具有明显减轻水土流失的作用 ,休闲处理能减少径流流失 4 2 .8% ,减少泥沙流失量 85 .0 2 % ;等高土埂处理能减少径流流失 70 .2 0 % ,减少泥沙流失量 95 .0 4 % ;水平草带能减少径流流失 3 2 .3 3 % ,减少泥沙流失量 4 5 .88% ;水平沟处理能减少径流流失 4 5 .6% ,减少泥沙流失量 63 % ;等高农作能减少径流流失 5 6.3 3 % ,减少泥沙流失量 87.70 %。等高土埂、等高农作、休闲处理减轻水土流失的作用优于水平草带和水平沟处理 ;泥沙流失除等高土埂和等高农作以外 ,其它处理均是推移质流失量大于悬移质流失量 ;径流流失和泥沙流失主要集中在 5～ 8月份 ,约占全年流失总量的 80 %以上。影响径流和泥沙流失的主要因素为降雨量、降雨侵蚀力、植被覆盖度等因素。     

论水土保持可持续发展

水土流失是当今世界的一大生态“公害”。无论是发达国家,还是发展中国家都存在不同程度的水土流失危害。我国是世界上水土流失十分严重的国家之一,虽然近年来我国的水土保持工作取得了一定的成绩,但随着人口、经济及城市化建设的迅速发展,各种因素造成的新的水土流失日趋严重。论述了水土流失对可持续发展带来的威胁,提出了实施可持续发展的水土保持战略建议,具有一定的现实意义和科学价值。     

赣州市水土流失态势及其防治对策

分析了赣州市60年代以来水土流失面积由上升至1988年后逐渐下降,而强度以上程度流失面积、土壤侵蚀流失量一直呈上升趋势及其成因,相应提出对水土保持要有更深层更全面的认识;要全面贯彻预防为主的方针,加大预防保护和监督执法力度;要得到各级领导、各部门和全社会的关注与行动;要集中人力、财力,以点带面主攻强度以上流失地区治理。     

不同生态退化类型的水土保持生态修复对策

根据我国水土流失的特点以及水土保持生态修复工程的实施现状,结合对生态修复的理解,从理念、方法、原理、重点、关键、目标、适宜区域和实质等方面阐述生态修复的内涵。在综合分析生态退化和水土流失成因与驱动因子的基础上,归纳出造成水土流失的5种生态退化类型,揭示不同生态退化类型水土流失的原因,并提出不同生态退化类型的水土保持生态修复对策。     

煤矿工程水土保持准入条件

 通过对煤矿工程类型组成、建设规模,以及煤矿工程建设与生产运行期间水土流失特点、水土流失治理措施等的调查研究,依据法律法规、产业政策、行业规划、技术标准等相关规定,提出煤矿工程水土保持基本准入条件10条、限批条件9条、缓批条件8条、6大水土流失类型区煤矿工程水土保持方案准入条件34条、须由主体设计进行修正的条件15条、须修改完善水土保持方案的条件2条,以及煤矿工程水土保持方案优先审批和暂缓审批的13条意见。     

Some factors influencing denitrification and nitrogen immobilization in a clay soil

Nitrate-N, enriched with ¹⁵N, was added to small cores of the 0–10 cm layer of a clay soil. The base of each core was sealed, then water, equivalent to 0, 10, 20 or 30mm of rain, was added to the soil surface. The cores were incubated for 1 week at 10, 20, or 30°C in the presence or absence of wheat straw. The recovery of ¹⁵N in the soil mineral-N and organic-N fractions was then measured.No significant losses of ¹⁵N were detected in the cores which received 0–10 mm of added water, and in which the soil water content was close to 0.56 g g^?1 (?10 kPa). However, ¹⁵N losses, assumed due to denitrification, were rapid from cores receiving 20 or 30 mm of water and incubated at 20–30°C. The onset of denitrification was quite sudden as the amount of added water increased from 10 to 20 mm. In this range, a small increment of added water apparently sealed a relatively large volume of soil from atmospheric O₂ diffusion. This phenomenon was strongly temperature-dependent since no losses were detected from any cores at 10°C even though the 30mm addition of water produced a thin layer of free water across the soil surface.The addition of straw did not promote denitrification in soil at water contents close to 0.56 g g^?1. At high soil water contents, adcling straw increased immobilization of labelled NO₃^? and so reduced denitrification losses. The response of immobilization to changing soil water and temperature conditions was very different from that of denitrification.     

Tillage, mineralization and leaching: phosphate

Phosphate is usually the limiting nutrient for the formation of algal blooms in freshwater bodies, so tillage practices must minimize phosphate losses by leaching and surface run-off from cultivated land. Mineral soils usually contain 30–70% of their phosphate in organic forms, and both organic and inorganic phosphate are found in the soil solution. Some organic phosphates, notably the inositol phosphates, are as strongly sorbed by soil as inorganic phosphates, and this decreases their susceptibility to mineralization. The strength with which both categories are sorbed lessens the risk of their being leached as solutes but makes it more likely that they will be carried from the soil on colloidal or particulate matter, and the greatest losses of phosphate from the soil usually occur by surface run-off and erosion. Recent studies at Rothamsted have, however, shown substantial concentrations of phosphate in drainage from plots that have long received more phosphate as fertilizer than is removed in crops. These losses probably occurred because preferential water flow carried the phosphate rapidly from the surface soil to the field drains. For lessening losses of phosphate by leaching and run-off, the prime requirement of tillage is that it should encourage flows of water through the soil that help it to retain phosphate. Primary and secondary tillage should ensure that the surface roughness and porosity of the top-soil encourage the flow of water into the soil matrix where it will move relatively slowly and allow phosphate to be sorbed, thereby avoiding problems from run-off and preferential flow. Inversion tillage can be useful for lessening the loss of phosphate by run-off and erosion. Secondary tillage could be used to decrease the size of the aggregates and increase the surface area for sorption. Although tillage will increase the mineralization of organic phosphate, pulses of mineralization are unlikely to be so rapid or to lead to such large losses as with nitrate. The strength with which phosphate is sorbed also lessens the problem. As with nitrate, the key to managing phosphate is basically good husbandry.     

Ecological intensification of cropping systems enhances soil functions,mitigates soil erosion,and promotes crop resilience to dry spells in the Brazilian Cerrado

Water scarcity threatens global food security and agricultural systems are challenged to achieve high yields while optimizing water usage. Water deficit can be accentuated by soil physical degradation, which also triggers water losses through runoff and consequently soil erosion. Although soil health in cropping systems within the Brazilian Cerrado biome have been surveyed throughout the years, information about soil erosion impacts and its mitigation are still not well understood; especially concerning the role of cropping system diversification and its effects on crop yield. Thus, the aim of this study was to assess whether ecological intensification of cropping systems –inclusion of a consorted perennial grass and crop rotation– could promote soil coverage and consequently decrease water erosion and soil, water, and nutrient losses. This work studied the effects of crop rotation and consorted Brachiaria, along with different levels of investment in fertilization on soil physical quality and on soil, water, and nutrient losses, and crop yields. Results proved that soybean monoculture (SS) is a system of low sustainability even under no-till in the Brazilian Cerrado conditions. It exhibited high susceptibility to soil, water, and nutrient losses, causing low crop yields. Our results showed that water losses in SS cropping system were approximately 10% of the total annual rainfall, and total K losses would require an additional 35% of K application. Conversely, ecological intensification of cropping systems resulted in enhanced soil environmental and agronomic functions, increased grain yield, and promoted soil and water conservation: high soil cover rate, and low soil, water and nutrient losses. Ecological intensification proved to be an adequate practice to boost crop resilience to water deficit in the Brazilian Cerrado.     

水土保持是生态环境建设的主体

论述了水土保持与生态环境的关系,分析了水土流失对生态环境造成的严重影响和由此造成的经济损失,搞好水土保持不但可以改善生态环境,而且提高了人民的生活水平。     

矿山开采水土流失现状与治理措施

为减少矿产资源开采过程中造成的水土流失,掌握矿区水土流失规律,探索矿区恢复治理模式,在分析矿山开采水土流失概况及其原因的基础上,总结相应的工程措施、植物措施、土地整治和复耕措施等治理措施,同时提出治理过程中严格执行"三同时"的原则.