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1.
城市污泥应用于毛白杨林地施肥试验   总被引:5,自引:0,他引:5  
为了妥善处置和利用城市污泥,使之变废为宝,采用城市污泥对毛白杨进行了不同立地施肥量、施肥时期试验.结果表明,污泥施肥改善了林地土壤的理化性状,对土壤具有修复作用.在不同施肥时期,不同立地条件下,施入一定量的城市污泥对毛白杨株高、胸径的生长均有促进作用,平原林地毛白杨净生长量优于丘陵地,污泥施入量以75 kg/株效果最佳.  相似文献   

2.
刘海 《绿色科技》2021,(6):49-52
由于城市污水处理厂在污水处置过程中产生污泥,污泥中存在有机物、重金属等超标污染物,如不能有效处理将对水源、空气和土壤环境造成污染,以苏州某污水处理厂存量污泥处置项目为研究对象,结合项目实施阐述了环境监理在污泥处置施工阶段的工作程序、二次污染防治、控制要点等内容,对处置过程中污泥开挖、固化稳定化、阻隔填埋等监理过程中控制难点和问题进行了探讨,提出了相应的建议,以期为后续污泥处置项目在施工阶段的环境监理提供参考。  相似文献   

3.
二道柳引种试验初报   总被引:1,自引:0,他引:1  
二道柳是北方的柳树杂交新品种,也是重要的造林绿化树种,其树干通直、分权少、不开裂、节疤少、颜色洁白,是十分理想的短轮伐期工业原料树种。为此,笔者对浙中地区二道柳的引种和栽培技术进行了试验研究。试验表明二道柳生长迅速,抗逆性强,它的生长量远高于普通柳树,采用高密度造林,集约栽培,3-4年轮伐能最大限度的获得单位面积的生物量,是一种适宜永康市及周边地区山沿田、低洼地、河滩栽培的柳树品种。  相似文献   

4.
洪泽湖大堤旱柳防浪林更新的问题与对策   总被引:1,自引:0,他引:1  
本研究从1990年开始对洪泽湖大堤迎湖面林台上新植的插干旱柳的生长进行了观察,对洪泽湖大堤的小气候因子、土壤因子进行了测定,分析了这些自然条件与柳树生长的关系以及病虫害、栽培技术对柳树生长的影响,从而明确了影响柳树成活的原因。针对柳树死因,设计了4种栽植方式并进行比较试验,优选出可以大幅度提高柳树更新成活率的最佳栽植方式,提出了提高柳树成活率的一套栽培技术措施。  相似文献   

5.
Two field trials were conducted to study the rate of release of nutrients and heavy metals from wood and peat ash fertilizers in forest soils. In the first experiment, ash particle residues were extracted from peat and mineral soils 3 and 5 years after spreading and analysed for changes in element concentrations. Dissolution of different ash fertilizer products was also estimated by measuring the changes over time in the recovery of added nutrients and heavy metals in the surface of two peat soils. The results showed that potassium (K), sodium (Na), boron and sulfur are easily released from wood ash, whereas heavy metals are highly insoluble in all types of ash fertilizer products. Granulated ash fertilizers were less soluble than powdered fertilizers and the products stabilized by self-hardening. Minor differences occurred in ash fertilizer dissolution between peat and mineral soils and soils of different fertility. The most significant difference between wood and peat ash concerning their dissolution was the low solubility of K and Na in peat ash. Given the very slow dissolution of ash fertilizers, long-term studies are needed to understand fully the effect of ash fertilization on nutrient and heavy metal cycling in forest ecosystems.  相似文献   

6.
A 3‐year field study was carried out to determine the effect of wastewater irrigation and previous differences in mineral fertilization on the occurrence of willow leaf rust (Melampsora epitea). The experiment was conducted in two energy forest plantations: one designed for wastewater purification and the other as a mineral fertilization experiment. The severity of leaf rust on different clones and sites with different treatments was assessed by counting the number of uredinia per leaf unit area. Generally, plants irrigated with wastewater consistently had more leaf rust, irrespective of the study years or willow clones. Previous mineral fertilization had mixed effects on different clones 2 years after the last application. Three years after the last fertilizer application, however, no impact of the treatment on rust disease development was detected. In general, the rust levels differed from year to year probably due to climate. In this study, no correlation was detected between shoot age and rust severity, whereas climate and treatments strongly influenced leaf rust levels on some willow clones.  相似文献   

7.
粉煤灰复田立地上杨,柳,榆,刺槐根系的分布和生长特点   总被引:22,自引:0,他引:22  
针对粉煤灰复田立地(利用电厂粉煤灰填充采煤塌陷区,在其上再覆30cm土壤)营造人工林的可行性和造林树种选择等问题,调查了该立地上生长的4—5年生欧美杨、旱柳、白榆和刺槐人工林根系的分布及生长特点。结果表明:四树种根系分布深达180cm以下,水平延伸达8m。在粉煤灰层中,各树种根系均能正常生长,其中根系长度和根系重量分别占总量的68%和87%以上。在30cm厚表层土壤中,根系长度和重量分别低于总量的30%和13%。欧美杨、旱柳、白榆和刺槐的根系总长度和总重量分别为每株49.24、29.45、25.42、68.08km和7.45、7.54、10.05、13.37kg。  相似文献   

8.
The levels of heavy metals that accumulated in stemwood of mature trees grown for 20 years in a plantation in an abandoned peat quarry in areas that were fertilized with different amounts of domestic sewage sludge(180,360,and720 Mg ha~(-1) on a dry basis) were compared with trees grown in a reference nonfertilized area.Included in the study was a hybrid poplar(Populus tremula x Populus tremuloides) developed for use as an energy crop,three local tree species and one introduced tree species.The concentrations of Cd,Cr,Cu,Ni,Pb and Zn in the stemwood of the trees grown in the fertilized and nonfertilized fields were determined,and found to be significantly lower than their respective concentrations in the soil.Cd and Cr were found only in several wood samples at concentrations close to the limits of detection or qualification; therefore,they were not analyzed further.A correlation analysis suggested that 75%of the correlations between the concentrations of heavy metals in the stemwood and the concentrations in the soil were negative.The ability of trees to accumulate the metals from soil in most cases decreased for Cu and Ni; however,the correlations were not as clear for Pb and Zn.The followingsequence for the levels of heavy metals found in the stemwood of the analysed trees was Zn [ Pb [ Ni [ Cu [(Cr,Cd).The results of this study showed that the levels of heavy metals in the studied wood would not exceed the permitted limits of heavy metal pollution in the air and ash when used for energy production.  相似文献   

9.
北京地区不同湿地植物对生活污水的净化效果研究   总被引:5,自引:0,他引:5  
选择北京地区芦苇、东方香蒲、水芹、睡菜和蒿柳5种湿地植物,设计6种不同的植物配置方式,研究不同湿地植物单种及其配置对水中pH值、化学需氧量(COD)、总氮(TN)和总磷(TP)的净化效果。通过连续6个月的动态监测,结果表明:湿地植物对污染物有明显的净化效果,且9月份前随着温度的升高和植物的生长逐步提高,9月份后净化效果上升趋势趋于缓和或下降。单种湿地植物中,东方香蒲对pH值净化效果最好,睡菜对COD净化效果最好,芦苇对TN净化效果最好,蒿柳对TP净化效果最好,东方香蒲、蒿柳对上述污染物的综合净化效果最好;从湿地植物单种和植物配置对污染物的净化效果比较来看,植物配置对pH值、TN的净化效果高于单种,而对COD和TP的净化效果低于单种,芦苇和睡菜适合与其他植物配置使用,而东方香蒲、蒿柳和水芹单种使用对污染物的综合净化效果高于与其他植物配置的效果。  相似文献   

10.
黄炳辉 《绿色科技》2013,(7):215-217
通过一个实例,分析介绍了生活垃圾焚烧炉渣分选处理的一种工艺。实践证明:综合利用破碎、筛分、磁力分选、跳汰分选、摇床分选等固废处理技术,对炉渣进行分选预处理,可有效回收利用Fe、Cu、Al等废旧金属,有效分离收集未燃尽的剩余垃圾,并妥善处理,从而使炉渣的性质满足资源化利用的技术要求,变废为宝。  相似文献   

11.
利用污水灌溉树木的研究进展   总被引:8,自引:0,他引:8  
文中从城市污水和工业废水经过处理后的排水进行分析,综述了国内外近年来利用各种污水灌溉树木的研究进展,通过分析表明,在一般情况下利用城市污水灌溉有利于树木生长,有些树木在工业废水再利用中能发挥重要作用,合理应用污水灌溉树木对未来防治污染具有一定的积极意义。  相似文献   

12.
The use of landfills as a disposal method for wood ash is costly, environmentally detrimental and is pitted against increasingly stern environmental regulations. Literature has shown that wood ash has the potential to be used as a forest fertiliser and the effects tend to be highly site-specific. Wood ash contains a combination of carbonates, hydroxides and other calcium-containing minerals that are responsible for the liming effect observed following application to soils. In addition, it contains significant magnesium and potassium concentrations, but little nitrogen and sulphur. The phosphorus availability of wood ash varies considerably and in effect can limit soil phosphorus uptake and may affect subsequent nutrient balance in plants. Short-rotation forestry practices and whole-tree harvest systems can induce periodic or persisting nutrient deficiencies and acidify the soil. This may affect the ability of a site to sustain adequate nutrient levels over successive rotations. Utilising wood ash as a soil amendment can offset or correct some nutrient deficiencies and imbalances induced by intensively managed plantation forests. This review covers the international literature on ash applications to forest land, including the effect of ash-beds remaining after slash burning (as a useful analogy for the effects of wood ash on soil properties and tree growth). The results show that ash applications to forest land can be done safely and can potentially stimulate microbial activity and improve pine and eucalypt growth. Safe ash application rates should be determined after consideration of (1) soil buffer capacity and ash alkalinity (expressed as calcium carbonate equivalence) and (2) an evaluation of the concentrations of heavy metals existing in soils and present in the available ash, particularly from cadmium, chromium, lead and arsenic.  相似文献   

13.
利用改进的CASA模型,结合Landsat TM遥感影像及气象数据,估算榆林飞播林2010年7月的植被净初级生产力。通过实测植被生物量,验证CASA模型在研究区的估算结果。结果表明:CASA模型适用于榆林飞播林植被净初级生产力估算;CASA模型估算的不同地区NPP区别明显,榆林市横山县与榆阳区交界处的植被NPP值最高,其值介233.21~414.15gC/m2之间;榆林飞播林生态系统属于较低生产力的生态系统;沙柳的NPP水平最高,以柠条+沙柳+沙蒿为播种模式的人工林地生物量最高;除沙柳、花棒和沙蒿外,其他飞播植物生物量与含水量无明显的相关性;不同飞播年代的同种植被生物量与含水量、土壤养分以及气候等因素之间具有密切的相关性。  相似文献   

14.
柳树无性系,变异大,形态多样,根据平原地区用材、防护、观赏的需要,对比分析柳树优良品种苏柳172、苏柳795、金丝垂柳1011和新选出的苏柳549、苏柳797、苏柳335、苏柳736、苏柳1034等新无性系的生长、冠形和枝干结构的差异。  相似文献   

15.
研究沙柳材预处理与未经处理刨花与水泥混合时的水化特性,以及添加助凝剂后上述2种情况的水化特性.结果表明:沙柳材对水泥具有强烈的阻凝作用.经冷、热水抽提处理后的刨花,再添加一定量的助凝剂,可用于水泥刨花板的生产.  相似文献   

16.
In the humid and temperate areas of southern Europe, forest plantations are dominated by fast-growing species (Eucalyptus globulus, Pinus radiata and Pinus pinaster), which are grown on acidic soils with low reserves of available nutrients. In this study the amounts of nutrients exported from the plantations under different regimes and intensities of harvesting were evaluated and, on the basis of the results obtained, silvicultural management methods aimed at improving the nutritional status of the plantations were proposed. We found high ratios between nutrients exported by harvesting and those available in soil stores, indicating limitation for P, Ca and Mg over the long term, which is consistent with frequently found deficiencies of these nutrients. Current harvesting practices (removal of stem wood and bark) result in high rates of export of P, K, Ca and Mg, especially in eucalypt plantations, because of the high productivity and low nutrient efficiency of this species. Comparison of the amounts of nutrients exported by harvesting, with natural inputs (rainfall and weathering) and outputs (stream water), suggests that intensive exploitation of these plantations may result in negative budgets, especially if whole tree harvesting is carried out. The application of fertilizers containing P, Ca and Mg should be encouraged in all cases to favour the return of nutrients, especially where logging residues are extracted. The cost of harvesting in terms of nutrients can also be reduced by careful selection of the tree species planted and of the tree fractions harvested and by reducing the intensity of harvesting.  相似文献   

17.
以东莞生态产业园内的人工湿地污水处理系统为研究对象,对比分析了系统内反硝化池、垂直流人工湿地、表面流人工湿地单元在高温期和低温期的污水净化能力,探讨了系统建成运行3年后,2013—2015年在固定水力负荷下的污水处理效果。结果表明,该人工湿地污水处理系统运行3年,净化能力保持稳定;相对于低温期,系统在高温期的污水处理效果不明显;反硝化池、垂直流人工湿地、表面流人工湿地各单元的污水处理能力不同,垂直流人工湿地对总磷、总氮的去除效果明显,反硝化池对氨氮的去除效果明显;表面流人工湿地相对于垂直流人工湿地,对各项水质指标值的去除效果不明显。作为人工湿地污水处理系统,应当重视表面流人工湿地对污水净化效果的影响。  相似文献   

18.
在水环境保护领域里,我国与世界大多数国家,都将控制由城市生活污水和各种工业、农业、养殖业排放的有机废水所导致的以有机质为主的水质污染放在优先考虑的地位。环境生物技术,尤其是生化处理方法因其高效、低耗、处理量大、适用面广及安全的特点而成为世界各国有机废水处理的主要方法。介绍了这一领域中以生化反应为基础的处理方法(好氧和厌氧处理工艺)和以生物自然净化功能为主体的技术措施(人工生物塘和湿地),以及相关研究与应用的进展动态。  相似文献   

19.
As willow (Salix) cultivation grows globally, worldwide monitoring of pathotypes for Melampsora rust, the most serious disease in willow, becomes increasingly important. We compared the pathotype composition of the Melampsora rust population in Chile with that in Sweden and assessed inocula exchange for the rust between the continents. For pathotyping rust isolates, a willow differential was used (a standardized set of willow test clones) to obtain clone‐virulence patterns. These patterns were used to identify virulence components involved in determining which willow clones a given individual pathogen isolate (genotype) can successfully attack. Each virulence component detected earlier in Sweden's rust population was present in Chile's rust population. Using isoenzyme analysis to classify willow species in Chile, a low genetic variation of Salix viminalis (an introduced willow species) was found, compared with the endemic species Salix humboldtiana. Comparison of rust populations for the two countries supports the present hypothesis that intercontinental inocula exchange can be a significant determinant of local pathotype structure, and consequently can be important for willow‐resistance breeding.  相似文献   

20.
在论述异龙湖流域森林植被、水土流失、社会经济及水环境等现状的基础上,对全流域的环境现状进行分析,认为主要的点源污染有城镇生活污水和工业废水,面源污染主要有农村生活污水、渔业生产废水,化肥农药流失和农村固体废弃物.藉此提出了开展防护林体系建设、湖泊生态修复等生态环境综合治理措施和对策.  相似文献   

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