Influence of soil phosphorus status,texture, pH and metal content on the efficacy of amendments to pig slurry in reducing phosphorus losses

Cost‐effective strategies for using chemically amended organic fertilizers need to be developed to minimize nutrient losses in surface and groundwater. Coupling specific soil physical and chemical characteristics with amendment type could increase their effectiveness. This study investigated how water‐extractable phosphorus (P) was affected by chemical amendments added to pig slurry and how this effect varied with soil properties. A 3‐month incubation study was conducted on 18 different mineral soils, stored at 10 °C and 75% humidity and treated with unamended and amended slurry which was incorporated at a rate equivalent to 19 kg total P (TP )/ha. The amendments examined were commercial‐grade liquid alum, applied at a rate of 0.88:1 [Al:TP ], and commercial‐grade liquid poly‐aluminium chloride (PAC ), applied at a rate of 0.72:1 [Al:TP ]. These amendments were previously identified by the authors as being effective in reducing incidental losses of P. The efficacy of the amendments varied with the soil test P, the degree of P saturation (DPS ) and the Mehlich aluminium, iron and calcium, but not soil texture. Chemical amendments were most effective in soils with DPS over approximately 20%. Due to their high cost, the incorporation of amendments into existing management practices can only be justified as part of a holistic management plan where soils have high DPS .     

沥青路面的水损害分析

本文对沥青路面的水损害进行了全面系统的分析 ,并提出了预防水损害具体措施 ,对指导设计与施工具有一定的现实意义     

The Brief Introduction to the Sino-US Joint Centers for Soil and Water Conservation and Environmental Protection

Erosion and transport of soil has worldwide implications for agriculture, landscape stability, climate, natural hazards, and clean, renewable resources of water and air. Assured access to clean water and a healthy and safe environment requires an ethic of conservation and protection. The minimum scale in which these principles apply successfully is basin wide. These are the fundamental concerns of the Sino-US Centers for Soil and Water Conservation and Environmental Protection.     

搞好水土保持 造福子孙万代

搞好水土保持造福子孙万代肖作福（辽宁省人民政府，沈阳１１００３２）从５０年代初期，辽宁省开始了水土保持工作的征程，现已走过四十多年的历程。辽宁人民在辽宁大地上，奋斗不息，重新描绘着山河面貌，谱写了水土保持工作的新篇章。辽宁省的自然状况是“六山一水三分...     

灌区节水改造对塔里木河流域治理的作用

在对塔里木河“四源一干”及流域大型灌区存在主要问题分析的基础上，探讨了大型灌区建戌节水改造,对工业及城镇生活需水增长、灌溉及周边生态环境用水、流域综合治理和社会经济可持续发展的作用，深入阐明大型灌区续建配套与节水改造对区域水资源合理配置生态及环境发展的重大意义。     

二甲硝咪唑盐的合成研究

本文报道以简便易行的方法合成水溶性二甲硝咪唑盐，收率高达95％以上，具工业化应用价值。     

猪场废水的生物处理技术及其效果

规模化养猪场所产生的废水污染，已成我国农村面临污染的重要来源。针对这种污染，近年来出现了多种养猪场废水处理法，其中研究和应用最广的是生物处理法。本文通过对目前国内猪场废水生物处理法的现状分析后认为：用生物处理法处理猪场废水是今后猪场废水处理的发展方向；而生物处理法自身的发展方向是混合处理法；计算机和生物工程技术将进一步与生物处理法相结合运用于猪场废水处理。     

Evaluation of a combined penetrometer for simultaneous measurement of penetration resistance and soil water content

A combined penetrometer is an appropriate tool to measure the soil cone resistance and the water‐content profile. As a relatively new technique, a combined capacitance‐penetrometer for the simultaneous measurement of cone index and soil water content was developed at the Department of Agricultural Engineering of Bonn University in 2002. The objective of this study was the evaluation of the effectiveness and applicability of the innovated penetrometer with a focus on three aspects: (1) A capacitance sensor with two electrode configurations was calibrated for silt loam, sandy loam, and sand. The calibration results show that both electrode configurations have sufficient water‐content sensitivity, but soil‐specific calibrations seem necessary. (2) Under laboratory conditions, the dynamic resolution and response of the capacitance‐penetrometer were validated, and its radius of influence was determined. (3) The field measurement results demonstrate that this measurement technique can be used to improve the interpretation quality of soil cone index data.     

沙土区薄壁连拱护岸墙试验与应用

沙土区薄壁连拱护岸墙为悬臂式支撑、薄壁连拱无底板结构，拱板中间采用无砂砼排水孔的钢筋砼肋形预制板，冲沉法施工，造价低廉；外形美观，抗倾、抗滑性能强。该墙为平原沙土区河道水土保持及修复找到了一条经济合理、施工方便、简便易行的护坡办法，具有较高的实用价值和广阔的推广使用前景。     

冷却水循环用离心泵汽蚀的原因与防止方法探讨

通过对冷却水循环用离心泵产生汽蚀的因素进行分析，提出了防止汽蚀产生的技术措施，经生产应用效果良好。