不同植被措施下排土场边坡细沟发育时空特征

为明确不同恢复年限植被措施对煤矿排土场边坡水土流失的防治效应,采用样方调查法,以内蒙古准格尔旗永利煤矿矿区排土场边坡为研究对象,以裸露边坡(CK)为对照,研究不同恢复年限(1a、3a、5 a)的沙柳方格+沙棘+沙打旺(SHA)和沙柳方格+沙打旺(SA)2种措施对细沟发育的影响。结果表明:(1)1a时CK、SHA与SA措施细沟宽度均集中分布在4～8 cm,细沟深度均集中分布在2～4 cm;3 a时CK、SHA与SA措施细沟宽度则集中分布在4～8 cm、8～12 cm、4～8 cm,细沟深度均集中分布在4～6 cm;5 a时CK与SHA措施细沟宽度均集中分布在8～12 cm,而细沟深度则集中分布在4～6 cm和8～14 cm;(2)CK(1～5 a)、SHA措施(1～5 a)和SA措施(1～3 a)的细沟平均宽分别为7.57～11.35 cm、7.58～13.31 cm和5.57～6.14 cm,细沟平均深分别为3.38～6.23 cm、4.19～10.34 cm、2.59～4.24 cm,三者的细沟平均宽深比分别为2.39、2.12和2.05,平均细沟密度分别为1.52～5.25 m·m–2、1.42～1.68 m·m–2和1.88～2.25 m·m–2;(3)1 a时CK、SHA和SA措施的细沟宽深比随坡长变化幅度较大,随着恢复年限增加,宽深比则呈下降趋势,CK、SHA措施和SA措施的细沟密度和细沟侵蚀量均随坡长增加呈增大趋势;(4)与CK相比,1 a时SHA和SA措施边坡细沟侵蚀模数分别减小25.0%和25.86%,两种措施减蚀效果差别不大,而3 a时则分别减小了61.73%和35.31%,SHA措施减蚀效果显著增强。研究结果可以为矿区排土场边坡的植被合理布设提供科学依据与理论指导。     

黄土丘陵区坡面薄层水流动力学特性及其对土壤侵蚀的影响

为奠定基于运动力学参数构建土壤侵蚀模型的理论基础,通过不同降雨强度(25、50和75 mm/h)、不同坡长(1、5、10、15和20 m)下径流小区内人工模拟降雨试验,对不同处理下坡面薄层水动力学特性进行分析,并对水动力学参数与土壤侵蚀之间的关系进行初步探讨。结果表明:当坡度一定时,坡面平均流速主要受坡长及单宽流量影响,降雨强度通过影响单宽流量的大小间接影响坡面平均流速;在试验设计范围内,当坡长1 m时,整体上呈"层流-急流态",当坡长为1 m时,整体上呈"层流-缓流态";当降雨强度一定时,雷诺数随着坡长的增加线性增加,佛汝德数随着坡长的增加以幂函数形式增加;降雨强度对坡面流有明显的"增阻"效应;坡面阻力系数随着坡长的增加呈幂函数减小趋势;坡面平均土壤侵蚀率与单宽流量间呈一元线性趋势增加,与水流平均流速间呈指数函数增加,与雷诺数间呈二次函数增加。     

The use of urban organic wastes in the control of erosion in a semiarid Mediterranean soil

Abstract. A two year field experiment was carried out in a semiarid Mediterranean area in order to evaluate, the effect on soil erosion of adding different urban organic wastes: a stabilized municipal waste (compost), an unstabilized municipal waste, and an aerobic sewage sludge. All the treatments significantly reduced soil erosion, compared to the control soil. The soil amended with compost was the most effective treatment, reducing soil loss by 94% and runoff by 54%.     

An evaluation of the pesera soil erosion model and its application to a case study in Zakynthos, Greece

Abstract. The Pan‐European Soil Erosion Risk Assessment (pesera ) model was evaluated using existing soil erosion data collected under various types of climate, vegetation, landscape and soil conditions. The data used represent a variety of typical Mediterranean land uses such as winter wheat, vines, olives and bare, stony land prevailing in hilly areas. Using this data, the model was calibrated for sediment transport by overland flow and results compared to measured soil erosion values from runoff plots and a watershed on a monthly basis. The performance of the model was assessed statistically, showing that it can be satisfactorily used for predicting soil erosion rates under the conditions included in the study. The overall model estimate including all the available experimental data was 0.69 t ha^?1 yr^?1 with a maximum error of 1.49 t ha^?1 yr^?1. After validation, the model was applied to a small watershed (60 ha) of great ecological importance for the sea turtle Caretta caretta. For this purpose, soil and vegetation maps were compiled from all the necessary data for applying the model. The model was run for three years using daily data from an existing nearby meteorological station. The predicted and measured soil erosion rates for a 7‐month period were 0.31 t and 0.18 t, respectively. Application of the model to each mapping unit showed the over‐riding importance of land use for sediment generation under the given climatic conditions. Bare land, occupying 5.5% of the watershed area, generated up to 69% of the total sediments estimated for the watershed. It is concluded that the pesera model can be used as a regional diagnostic tool under a range of soil, topographic and climatic conditions for identifying the best land use type and vegetation cover to protect hilly areas from soil erosion. The calculated overall root mean square error for the model is 0.06 t ha^?1 yr^?1, compared to a soil erosion rate of 0.04 t ha^?1 yr^?1, which can be tolerated for protecting the area for the sea turtle.     

上虞海涂实验农场中心试验区排水系统探讨

上虞市海涂实验农场中心试验区的排水系统，能满足十年一遇的年最大２４ｈ降雨，两天内排出的要求。滨海盐土的地下水位高，农田基本建设除用浅、密的排水沟布置外，还应结合平整土地、发展灌溉以及适用的农、林技术等综合措施，才能达到治盐改土的效果。     

Mangroves as indicators of coastal change

In view of the unique biological characteristics of mangroves, it is interesting to assess the extent to which these ecosystems can be used as indicators of coastal change or sea-level rise. From recent studies of mangrove mortality at several locations (including Guiana, Gambia, Côte d'Ivoire, Kenya, India and Bangladesh), it appears that these coastal ecosystems are so specialized that any minor variation in their hydrological or tidal regimes causes noticeable mortality. Each species of mangrove (but particularly those belonging to the genera Rhizophora, Bruguiera, Sonneratia, Heritiera and Nypa) occurs in ecological conditions that approach its limit of tolerance with regard to salinity of the water and soil, as well as the inundation regime. If the duration of daily immersion were to be modified by tectonic, sedimentological or hydrological events, the species either readjusts to the new conditions or succumbs to unsuitable conditions. Consequently, the use of remote sensing data for mangrove ecosystems offers excellent potential as a tool for monitoring coastal change.     

澳门海岸防护林多树种配置造林效果分析

对澳门凼仔岛海岸山地防护林造林地 (8年生 )进行调查 ,分析了林分保存率、林分生长量、各树种平均胸径、平均树高、林分土壤肥力和林分植被变化情况。认为海岸山地防护林营造多树种阔叶混交林是一种值得研究推广的林分改造模式     

Re-defining tillage erosion: quantifying intensity–direction relationships for complex terrain

Abstract. Current tillage erosion models account for the influence of tillage direction in the magnitude of the soil (tillage) transport coefficient. It is argued here that this is counter-intuitive and causes significant problems in modelling tillage erosion in areas of complex terrain. This article examines whether a re-modelling of tillage erosion is possible that separates tillage direction (an interaction with the landform) from the soil transport coefficient (a measure of tillage intensity representing the combination of implement erosivity and soil erodibility). Experimental data for mouldboard ploughing upslope, downslope and cross-slope at Coombe Barton Farm, Devon are examined. Integration of data for all directions into a single relationship, which relates translocation in the direction of tillage to slope in the direction of tillage and translocation perpendicular to tillage to slope perpendicular to tillage, is not possible using previously published methods of analysis. However, when total translocation distance is regressed against the tangent of the slope at 45° to the tillage direction (bisecting the tillage direction and the direction of overturning) it is found that a single relationship can be used to describe tillage in all three directions. Therefore, this relationship is used to determine a single value of the soil transport coefficient ( k _fTa) for constant soil and implement conditions but different tillage directions. This redefinition of tillage is important both for true estimation of tillage erosion severity, the adirectional coefficient being 40% larger than the directional coefficient, and for modelling of tillage erosion in complex terrain. These improvements are vital when tillage erosion simulation is used to direct soil conservation strategies.     

土壤风蚀研究进展与评述

按照时间顺序，分阶段论述了国内外风蚀研究的概况及成果，系统地总结与评述了国内外土壤风蚀研究的进展，指出把土壤风蚀研究与农田耕作制度的研究结合起来，将是以后研究的重要方向。     

中国风水侵蚀交错区分布特征分析

风水侵蚀交错带的研究 ,对景观、土地覆盖 /土地利用、全球变化等研究具有重要意义。论文以GIS技术为支撑 ,定量计算出我国风水侵蚀带。在分布特征上 ,主要分布我国北方地区 ,其中以西部沙漠 ,北部山脉沿线为重 ,这种分布与气候、地貌分界有明显联系。 49.6 %风水侵蚀复合带的降水量小于 2 0 0mm。风水侵蚀复合带的土地利用主要以草地为主 ,占 41.8% ,其次为耕地。两种类型的分布 ,草地以与其它土地利用类型交错分布为主 ;而耕地是有重心的分散分布。风水侵蚀复合带的总体侵蚀要强于全国水平。