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1.
为了探究脱硫石膏改良盐碱土的最佳施用量,以新疆玛纳斯河流域石河子绿洲盐碱地为研究对象,研究脱硫石膏不同施用量对小麦产量以及土壤理化性质的影响,并对脱硫石膏改良盐碱土壤进行安全性评价。研究表明:脱硫石膏施用量2 t·(667 m~2)~(-1)(2 t)比施用量为1 t·(667 m~2)~(-1)(1 t)、3 t·(667 m~2)~(-1)(3 t)更有利于降低土壤容重、增加土壤孔隙度;对土壤pH和电导率降低能力表现为2 t3 t1 t;2 t处理土壤中Na~+、K~+、Mg~(2+)含量均低于1 t和3 t处理;脱硫石膏量为2 t·(667 m~2)~(-1)对小麦产量增加效果最好,2 t处理较3 t和1 t处理产量分别增加9.48%和2.21%,综合评价脱硫石膏施用后对土壤改良效果及作物产量,以施用量2 t·(667 m~2)~(-1)作用效果显著。  相似文献   

2.
为克服烟气脱硫石膏改良盐碱地存在的土壤盐分升高、营养物质降低等不足,通过对不同重量配比的园林废弃物堆肥与适量烟气脱硫石膏混合施用,且开展了其对上海南汇滨海盐渍土的改良效应研究。结果表明:2种改良剂混合施用能显著降低滨海盐渍土pH和全盐含量,增加土壤营养物质含量和植物生物量,并提高植物对营养物质的吸收能力;与对照相比,当烟气脱硫石膏施用量为25 g·kg~(-1)时,土壤pH降低了10.9%,EC升高了8.4%,有效磷、有效氮和速效钾含量分别降低了30.1%、 40.5%和36.1%,黑麦草发芽率下降了8.0%,植株内全氮、全钾含量均有所升高,但全磷含量减少了25.4%;混合施加不同重量配比的园林废弃物堆肥后,土壤pH降幅为6.8%~13.8%, EC降幅为4.2%~11.6%;土壤有效磷、有效氮和速效钾含量增幅分别为96.0%~182.7%、40.0%~186.7%和71.7%~157.5%;黑麦草发芽率和生物量逐渐增加,在园林废弃物堆肥施用量为40%时,与对照处理相比,此时植物发芽率达到90.0%,总湿重、地上干重、株高和根长等分别增加了154.1%、100.0%、89.2%和103.6%,植株体内氮和钾含量分别增加了139.9%和40.8%,磷的含量则接近对照处理。通过分析可知,烟气脱硫石膏和园林废弃物混合施用可较好地改良滨海盐渍土壤,并为城市固废的适合处置方式和综合利用途径提供了参考。  相似文献   

3.
通过田间试验,探讨了沼肥对甘薯的增产效应及其对甘薯品质、重金属吸收的影响.结果表明:(1)增施沼肥可以显著提高甘薯产量,施用30.0 t/hm2沼肥的甘薯产量最高,增产29.1%.(2)甘薯的不同器官中粗蛋白含量存在差异.甘薯叶中粗蛋白含量最高,甘薯藤中含量次之,而果实中含量最低.为了提高甘薯中粗蛋白含量,沼肥施用量应低于10 t/hm2.(3)施用沼肥对甘薯对铜的吸收没有显著影响;过量沼肥施用会促进甘薯对锌的吸收.沼肥施用对甘薯不同器官吸收铜、锌的影响依次为甘薯叶>甘薯藤>甘薯果实.(4)优质甘薯种植中沼肥施用量不宜超过10 t/hm2,如果考虑土壤重金属和氮素累积风险,保证土壤安全的甘薯沼肥科学施用量宜为6.1 t/hm2.  相似文献   

4.
环保型节氮肥料——脲铵在晚稻上的施用效果研究   总被引:1,自引:0,他引:1  
在晚稻上施用脲铵与尿素,探索脲铵和尿素对水稻产量与氮肥吸收利用率(REN)的影响效果.结果表明:(1)尽管两种氮肥含氮量不同,但施用脲铵处理的折施纯氮量比尿素处理减少34.78%,晚稻产量并不减少,反而略有增加.(2)为了保证水稻产量、提高REN,当地水稻种植选择脲铵代替尿素作为氮肥效果较好,且推荐施用脲铵量为450~525 kg/hm2为宜.(3)施用脲铵量较高的REN优于施用量较低,施用脲铵525~600 kg/hm2(折施纯氮量为157.5~180.0 kg/hm2)时,REN为34%左右;施用脲铵375~450 kg/hm2时,REN约低5百分点.(4)在不施用有机肥料的条件下,从植株吸收氮量看,折施纯氮量180~200 kg/hm2,才能达到氮素收支基本平衡.因此,适量施用脲铵并配施有机肥或稻草还田,可以缓解氮素不平衡的问题.  相似文献   

5.
高寒地区刺儿菜对重金属镉污染土壤修复效果研究   总被引:2,自引:0,他引:2  
为探究刺儿菜在不同施肥水平下对土壤重金属的修复作用与效果,对研究区进行了不同尿素水平的施肥试验,并定量分析了其试验结果。结果表明:施用231.5~925.9kg/hm2尿素,刺儿菜地上部分生物量和镉积累量均显著提高,镉提取率与对照组相比升高了15.44%~35.12%,施用694.4kg/hm2尿素时效果最佳。刺儿菜对镉的转移系数和富集系数均大于1,具备超富集植物的基本特征,可作为该污染区土壤修复的乡土植物。  相似文献   

6.
研究了湘西地区常用的发酵鸡粪和有机磷肥施用对不同程度Pb、Cd复合污染土壤中乙三胺五醋酸(DTPA)提取态Pb(DTPA-Pb)、DTPA提取态Cd(DTPA-Cd)和土壤酶的影响,并研究了对于种植黑麦草(Lolium perenne L.)的影响。结果表明:(1)施用发酵鸡粪和有机磷肥均能显著改善土壤酸性,一定程度上提高土壤有机质含量。在加入质量浓度200mg/kg总Pb、2mg/kg总Cd复合污染土壤中施用有机磷肥,能有效钝化土壤DTPA-Pb、DTPA-Cd,但在400mg/kg总Pb、4mg/kg总Cd复合污染土壤中钝化效果有限,其优先钝化DTPA-Pb。施用发酵鸡粪不能有效钝化土壤DTPA-Pb、DTPA-Cd。(2)施用发酵鸡粪和有机磷肥均显著提高黑麦草鲜重。虽然施用有机磷肥能更有效的钝化土壤DTPA-Pb、DTPA-Cd,但对于黑麦草种植而言,施用发酵鸡粪能更有效的降低其对Pb和Cd的积累,并且主要积累到根部。(3)施用发酵鸡粪对土壤碱性磷酸酶活性、脱氢酶活性和脲酶活性有显著的促进作用。综合而言,湘西地区种植牧草黑麦草,施用发酵鸡粪比较合适,能有效改善土壤酸性,提高黑麦草鲜重和土壤酶活性,降低黑麦草对Pb和Cd的积累。  相似文献   

7.
建立模拟降雨装置,研究降雨条件下功能性材料与聚合物对降水土壤渗透性与地表径流污染负荷的影响.研究证实,沸石与PAM不仅能够促进降雨土壤水的入渗、延缓并减少地表径流,而且使土壤渗液和地表径流水质TSS、TN、TP、COD污染物负荷降低.以3 kg/hm2 PAM、3 kg PAM与7.5 t/hm2沸石、6 kg/hm2 PAM 3种方式处理,径流COD负荷为对照的39.12%~69.76%、26.14%~46.63%和20.60%~28.09%;TN、TP与TSS负荷较对照分别减少44.36%~96.47%、66.63%~98.99%、93.71%~99.62%和50.46%~98.40%、83.30%~99.31%、94.91%~99.72%和31.06%~77.23%、46.82%~86.22%、83.54%~95.33%.聚合物与功能性材料改良土壤是一种削减地表降雨径流非点源污染的有效手段.  相似文献   

8.
电动修复不同形态铬污染土壤的研究   总被引:3,自引:0,他引:3  
研究了土壤中铬的价态对电动修复效率的影响以及电动修复前后土壤中铬形态的变化.结果表明,电动修复对于土壤中1 000 mg Cr(Ⅵ)/kg的去除效果明显,总铬去除率达59.7%;而对1 000 mg Cr(Ⅲ)/kg的去除效率较低,仅为6.2%;Cr(Ⅲ)和Cr(Ⅵ)(各500 mg/kg)同时污染的土壤,铬的去除率介于中间,为18.7%.电动修复前后,土壤中铬的形态也发生了明显的变化.其中,电动修复对土壤中Cr(Ⅵ)的提取形态影响最大,而对Cr(Ⅲ)提取形态并无太大的影响.总体上,电动修复后对于生物有效的弱酸可提取态铬的浓度都保持在较低水平,预期铬的环境风险(物理流动性和生态风险)将大大降低.  相似文献   

9.
为了探索污泥堆肥中重金属在土壤-植物系统中的积累与转移特性,通过温室盆栽实验,分析了污泥堆肥对草坪草高羊茅、黑麦草和白三叶生物量积累的情况,研究了污泥堆肥中Zn和Cu在植物和土壤中的分布特征。结果表明,污泥堆肥施用可以有效促进3种草坪草的积累生物量,在0~6 kg/m2的污泥堆肥施用量范围内,草坪草的生物量积累随着施用量的增加而提高。土壤中Zn和Cu的含量随污泥堆肥施加量的增加而增大,85%以上的Zn和Cu残留在土壤中。污泥堆肥中的Zn和Cu均可以被植物吸收,随着污泥堆肥施用量的增加,草坪草对Zn和Cu的吸收量增大,但当污泥堆肥施用量超过一定阈值时,草坪草吸收Zn和Cu不再增加,甚至减少;对于不同的草坪草,这一阈值有所不同。植物对Zn和Cu的吸收量只占土壤中Zn和Cu减少量的5%左右。根据生物富集系数(BCF)的计算结果推测,污泥堆肥的施用对土壤环境的影响大于对植物体内累积Zn和Cu的影响。  相似文献   

10.
以白龙港污水处理厂产生的生活污泥为研究对象,采用田间试验开展了污泥土地利用对滨海盐渍土肥力改良效果的研究.结果表明:(1)与对照处理相比,施用熟化污泥后,在整个试验过程中,土壤pH均可不同程度降低,其中施用2.5%(质量分数,下同)熟化污泥的处理,一年后与对照处理相比,pH降低了0.41个单位,降幅达到4.79%,而其他处理间差异不显著(P>0.05).各处理的土壤电导率(EC)均在植物正常生长限值(1.3mS/cm)内,表明熟化污泥中盐分含量不是其土地利用的限制因子.(2)熟化污泥施用土壤一年后,除速效钾外,均可不同程度增加土壤中有机质(SOM)、碱解氮、有效磷、全氮、全磷、全钾含量.(3)施用熟化污泥后,土壤容重总体有略微下降的趋势.这说明,熟化污泥可在一定程度上改善土壤结构,但不同的污泥施用量,对土壤容重影响程度不同.  相似文献   

11.
脱硫石膏农业利用研究进展与展望   总被引:15,自引:0,他引:15  
概述火电厂脱硫石膏定义、生产过程和性质。简述了脱离石膏的工业利用,详述了脱离石膏对酸性和碱性土壤改良的现状和机理,并展望了脱硫石膏促进滩涂土植被演替的前景。  相似文献   

12.
概述火电厂脱硫石膏定义、生产过程和性质.简述了脱离石膏的工业利用,详述了脱离石膏对酸性和碱性土壤改良的现状和机理,并展望了脱硫石膏促进滩涂土植被演替的前景.  相似文献   

13.
Applying manure compost not only results in zinc accumulation in the soil but also causes an increase in zinc mobility and enhances zinc leaching. In this study, the physical and chemical characteristics of zinc, zinc profiles, and zinc balance were investigated to characterise the fate of zinc in fields where the quality and amount of pig manure compost applied have been known for 13 years. Moreover, we determined zinc fractionation in both 0.1 mol L?1HCl-soluble (mobile) and -insoluble (immobile) fractions. Adsorption of zinc in the soil was enhanced with increasing total carbon content following the application of pig manure compost. The 159.6 mg ha?1 year?1manure applied plot (triplicate) exceeded the Japanese regulatory level after only 6 years of applying pig manure compost, whereas the 53.2 mg ha?1 year?1 manure applied plot (standard) reached the regulatory level after 13 years. The zinc loads in the plots were 17.0 and 5.6 kg ha?1 year?1, respectively. However, 5.9 % and 17.2 % of the zinc loaded in the standard and the triplicate pig manure compost applied plots, respectively, were estimated to be lost from the plough layer. Based on the vertical distribution of mobile and immobile zinc content, a higher rate of applied manure compost caused an increase in the mobile zinc fraction to a depth of 40 cm. Although the adsorption capacity of zinc was enhanced following the application of pig manure compost, a greater amount of mobile zinc could move downward through the manure amended soil than through non manure-amended soil.  相似文献   

14.
Abstract

Dissipation, degradation and leaching of fresh 14C coumaphos, alkylated 14C coumaphos and aged residues of 14C coumaphos from vats were studied in alkaline sandy loam soil in soil columns in the field under subtropical conditions in Delhi for a year. Dissipation, degradation and bound residue formation was more in case of alkali treated coumaphos than fresh coumaphos. After 365 days total residues of fresh coumaphos accounted for 33.25% while that of alkali treated coumaphos was 19.12%. Bound residue formation was almost double in case of alkali treated coumaphos (18.95%) than fresh coumaphos (9.53%) after 150 days followed by release of bound residue in both the cases. The proportion of metabolites 4 ‐ methylumbelliferone, chlorferon and potasan collectively was 86.05% in fresh coumaphos extractable residues while the same was 91.74% in alkali treated coumaphos after 365 days. Aged residues from vats containing copper sulphate and buffer were found to be more persistent in soil as total residues remained were 95.58% in comparison with 83.09% total residues of aged residues from vats containing only buffer after 150 days of treatment. Copper sulphate seems to inhibit the degradatiion of coumaphos in soil by microorganisms. Chlorferon was the major metabolite in generally all the samples. Coumaphos did not leach below 10 cm in all the cases.  相似文献   

15.
This work focused on the interactive effects of the fungicide chlorothalonil (2,3,4,6-tetrachloro-1,3-benzendicarbonitrile) and gypsum on the persistence of the soil-residual herbicide metolachlor (2-chloro-N-(6-ethyl-o-tolyl)-N-[(1RS)-2-methoxy-1-methylethyl]acetamide). Gypsum application was included due to its widespread use on peanut (Arachis hypogaea). Both agricultural grade gypsum and reagent CaSO4-2H2O were tested. A laboratory soil incubation was conducted to evaluate interactive effects. Results indicated 1.5X greater metolachlor half-life (DT50) in soil amended with chlorothalonil (37 d) as compared to control soil (25 d). The two gypsum sources alone increased metolachlor DT50 to about 32 d and with the combination of chlorothalonil and gypsum, DT50 was 50 d, 2-fold greater than the control. Chlorothalonil dissipation was rapid (DT50 < 4d). A possible explanation for metolachlor dissipation kinetics is a build-up of the chlorothalonil intermediate (4-hydroxychlorothalonil) which limited soil microbial activity and depleted glutathione S-transferase (GST) from chlorothalonil detoxification. Further information related to gypsum impacts is needed. Results confirm previous reports of chlorothalonil impeding metolachlor dissipation and showed the gypsum application extended persistence even longer. Farming practices, such as reducing metolachlor application rates, may need to be adjusted for peanut cropping systems where chlorothalonil and gypsum are used.  相似文献   

16.

The water balance for the site Mühleggerköpfl in the North Tyrolean Limestone Alps has been established to a soil depth of 50 cm. The evaporation amounts to 42% and deep percolation is 58 % of the precipitation. The surface runoff was negligible and therefore the according nitrate fluxes as well. Soil water analysis revealed mean nitrate concentrations of 3 to 15 mg NO3 L−1, depending on soil depth. The nitrate concentrations at 50 cm soil depth and the associated percolation rates led to NO2 N outputs of 15.9 kg NO3 N ha−1 in the year 1999 and 7.9 kg NO3 N ha−1 in the year 2000.

  相似文献   

17.
新型改性聚丙烯酰胺的合成及对污泥调理效果的研究   总被引:1,自引:1,他引:0  
采用原位聚合法,在聚丙烯酰胺的聚合过程中引入金属离子进行改性,合成了一种新型改性聚丙烯酰胺.通过正交实验确定了改性聚丙烯酰胺的最佳合成条件.红外图谱显示,该聚丙烯酰胺是一种具有特殊结构的有机高分子化合物.以污泥脱水率和污泥比阻为考察指标,研究了改性聚丙烯酰胺对污水处理厂剩余活性污泥脱水性能的影响,结果表明,在每1000...  相似文献   

18.

Dissipation and leaching behavior of 14C-monocrotophos was studied for 365 days under field conditions using PVC cylinders. The first set (24 cylinders) was spiked with 1.0 μCi 14C-labeled monocrotophos along with 1.06 mg unlabeled monocrotophos to give a concentration of 2 mg kg ?1 in the soil up to 15 cm depth. The second set (24 cylinders) received 14C-labeled monocrotophos along with other non-labeled insecticides viz., dimethoate @ 300 g a.i ha?1, deltamethrin @ 12.5 g a.i ha?1, endosulfan @ 750 g a.i ha?1, cypermethrin @ 60 g a.i ha?1, and triazophos @ 600 g a.i ha?1 at an interval of 15 days each as recommended for the cotton crop. 14C-monocrotophos dissipated faster, up to 45% in first 90 days in columns treated with only monocrotophos compared to 25% in columns that received monocrotophos along with other insecticides. However, both the columns showed similar residues 180 days onward. After 180 days of treatment, 46% radiolabeled residues were observed, which reduced up to 39.6% after 365 days. Leaching of 14C-monocrotophos to 15–30 cm soil layer was observed in both the experimental setups. In the 15–30 cm soil layer of both soil columns, up to 0.19 mg 14C-monocrotophos kg?1d. wt. soil was detected after 270 days.  相似文献   

19.
The present study aimed to investigate the NH3 volatilization loss from field-applied compost and chemical fertilizer and evaluate the atmosphere–land exchange of NH3 and particulate NH4+ (pNH4) at an upland field with volcanic ash soil (Andosol) in Hokkaido, northern Japan. Two-step basal fertilization was conducted on the bare soil surface. First, a moderately fermented compost of cattle manure was applied by surface incorporation (mixing depth, 0–15 cm) at a rate of 117 kg N ha−1 as total nitrogen (T-N) corresponding to 9.9 kg N ha−1 as ammoniacal nitrogen (NH4–N). Twelve days later, a chemical fertilizer containing 10% (w/w) of NH4–N as a mixture of ammonium sulfate and ammonium phosphates was applied by row placement (cover depth, 3 cm) at a rate of 100 kg N ha−1 as NH4–N. The study period was divided into the first-half, beginning after the compost application (CCM period), and the second-half, beginning after the chemical fertilizer application (CF period). The mean air concentrations of NH3 and pNH4 (1.5 m height) were 7.6 and 3.0 μg N m−3, respectively, in the CCM period; the values were 3.7 and 3.9 μg N m−3, respectively, in the CF period. The composition ratios of NH3 to the sum of NH3 and pNH4 (1.5 m height) were 72% and 49% in the CCM and CF periods, respectively. The NH3 volatilization loss from the compost was 0.8% of the applied T-N (or 9.3% of the applied NH4–N) and that from the chemical fertilizer was near zero. Excluding the period immediately after the compost application, the upland field acted as a net sink for NH3 and pNH4.  相似文献   

20.
乌梁素海湖滨带盐碱土碱化参数与特征分析   总被引:1,自引:0,他引:1  
为了研究乌梁素海湖滨带,不同植被的土壤盐碱特征,测定了乌梁素海湖滨带盐碱土的碱化度(ESP)、钠吸附比(SAR)、总碱度、pH值和含盐量等指标,分析了该类型的土壤的简化特征及其垂直分布态势.结果表明,乌梁素海湖滨带土壤可溶件例子组成以Na+、SO2-4-和Cl-为主,各土层中Na+占阳离子总量比例平均多在63.6%以上...  相似文献   

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