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101.
102.
现代汉语规范词汇中有“燥热”而无“躁热”。笔者认为“躁热”不该被规范掉,理由有三个:第,“燥”与“躁”不同的意符,就是二者不同的区别语素。第二《,现代汉语词典》中没有“燥热”吞并或替代躁热的依据,释义时留下了缺憾。第三,恢复“躁热”应有的地位应该是利大于弊,规范词汇不能简单的看是否增加记忆的负担。 相似文献
103.
蔗叶还田配施化肥在赤红土蔗地上的效应研究 总被引:10,自引:0,他引:10
采用正交试验设计,研究蔗叶还田配施化肥在赤红土上的改土培肥和增产效果,试验表明,蔗叶还田结合增施化肥能加速有机质的积累,改善赤红土的物理性状,增加土壤有效磷和有效钾的供应,促进甘蔗生长,提高甘蔗产量。 相似文献
104.
垂直对撞流干燥的试验研究 总被引:1,自引:0,他引:1
设计了新型的对撞室结构,在自行研制的垂直对撞流干燥试验台上进行了物料的适应性试验以及结构参数、操作参数对干燥效果的影响试验,获得了垂直对撞流干燥的一般规律,为对撞流干燥机的设计和生产应用积累了可靠依据。 相似文献
105.
利用室内培养实验,分析燥红壤和砖红壤中分别施加N0(不添加氮素)、N1(氮添加量为100mg·kg−1)、N2(氮添加量为200mg·kg−1)和N3(氮添加量为300mg.kg−1)4个水平氮后对土壤性质及N2O、CO2排放的影响。结果表明:氮肥添加显著降低了土壤pH和有机碳含量。相较于N0,燥红壤N1、N2和N3处理pH和有机碳降幅分别为8%~18%和4%~12%,砖红壤降幅分别为5%~23%和3%~15%;添加氮肥后各处理土壤全氮含量显著增加,燥红壤和砖红壤分别增加15%~54%和13%~52%。氮施入增加了土壤NH4+−N和NO3−−N含量,各处理土壤铵态氮和硝态氮含量均表现为N3>N2>N1>N0。氮添加促进土壤N2O和CO2排放,相较于N0,燥红壤N2O和CO2累积排放量分别增加1176%~2425%和124%~281%,砖红壤分别增加1054%~1887%和138%~256%。施氮量和土壤类型是影响农田土壤N2O和CO2排放的重要因素。土壤N2O和CO2排放与施氮量呈线性显著相关,减少施肥是降低土壤N2O排放最直接和最有效的措施。与砖红壤相比,燥红壤N2O和CO2排放对氮素添加的响应更敏感。 相似文献
106.
107.
云南小江流域土壤侵蚀十分严重,为揭示其侵蚀机理及探索有效治理方法,对其典型土壤——燥红土不同土地利用类型开展了人工降雨产流产沙试验,并运用水分测定仪(TRASE 6050X1 TDR)对土壤水分变化进行动态监测。结果表明:灌草地蓄水拦沙能力最强,坡耕地(坡式梯地沿等高线开挖垄沟种植花生)次之,裸坡地最弱;同种利用类型土壤不同土层传输水分和吸收水分能力不同;在较大雨强(0.61mm/min)且充足降雨条件下,小江流域燥红土地表产流特征经历了以超渗产流为主、超渗产流和饱和产流同时进行、以饱和产流为主的3个阶段。 相似文献
108.
氮肥对磷在红壤肥域微域中迁移和转化的影响 总被引:12,自引:0,他引:12
The effects of two different nitrogen fertilizers (urea and NH4C1) with monocalcium phosphate (MCP) on the movement and transformation of fertilizer P in soil microsites along with soil pH changes at different distances from the fertilizer application site were studied in an incubation experiment. A highly acidic red soil (Ultisol, pH 4.57) from south China with MCP fertilizer alone or in combination with NH4C1 or urea was added to the surface of soil cylinders and packed in wax blocks. After 7 and 28 days, the extraction and analysis of each 2 mm layer from the interface of the soil and fertilizer showed that added NH4C1 or urea did not change the movement distance of fertilizer P. However, P transformation was significantly affected (P 〈 0.05). After 7 days, at 0-8 mm distance from the fertilizer site the addition of urea significantly decreased the water-extractable P concentration; however, after 28 days the effect of N addition had disappeared. Also,at limited distances close to the fertilizer site NH4Cl application with MCP significantly increased acid-extractable P and available P, while with the addition of urea they significantly decreased. Compared with application of MCP alone,addition of urea significantly increased soil pH in fertilizer microsites, whereas the addition of NH4Cl significantly decreased soil pH. 相似文献
110.
可溶性有机物对土壤中绿麦隆吸附与解吸的影响 总被引:7,自引:0,他引:7
A batch equilibrium techniques was used to examine the effect of dissolved organic matter (DOM) extracted from both non-treated sludge (NTS) and heat-expanded sludge (HES) on the sorption and desorption of chlorotoluron (3-(3-chloro-p-tolyl)-1,1-dimethylurea) in two types of soils, a yellow fluvo-aquic and a red soil from China. Without DOM,sorption of chlorotoluron was significantly greater (P 〈 0.05) in the red soil than in the yellow fluvo-aquic soil. However,with DOM the effect was dependent on the soil type and nature of DOM. Chlorotoluron sorption was lower in the yellow fluvo-aquic soil than in the red soil, suggesting that with the same DOM levels the yellow fluvo-aquic soil had a lower sorption capacity for this herbicide. Application of DOM from both NTS and HES led to a general decrease in sorption to the soils and an increase in desorption from the soils. Desorption of chlorotoluron also significantly increased (P 〈 0.05) with an increase in the DOM concentration. Additionally, for sorption and desorption, at each DOM treatment level the NTS treatments were significantly lower (P 〈 0.05) than the HES treatments. This implied that non-treated sludge had a greater effect on the sorption and desorption of chlorotoluron than heat-expanded sludge. 相似文献