绿化植物废弃物和污泥的堆肥特性研究

绿化植物废弃物和污泥不同比例的堆肥实验显示其质量比为5∶4时堆肥升温快,高温持续时间最长;全碳和全氮含量在堆肥14 d后都有明显的降低;NO3--N的含量变化不大;NH4+-N的含量降低;堆肥的富里酸(FA)快速降低,胡敏酸(HA)先略有降低,然后快速增加;而种子发芽指数在14 d后均超过了0.8;最终腐殖质化参数(HI)为2.71,腐殖化速率(HR)为14.87%,CFA/CO=10.8;重金属的含量符合相关堆肥标准要求。绿化植物废弃物的高木质素含量决定了C/N、T值(终点C/N)/(初始C/N)、NH4+-N/NO3--N不宜作为其腐熟评价指标,但温度、NO3--N和NH4+-N、腐殖化参数、种子发芽指数可作为绿化植物废弃物和污泥混合堆肥的腐熟评价指标。绿化植物废弃物和污泥混合堆肥效果取决于污泥的添加量,含水量高的污泥用量过多会影响堆肥效果。绿化植物废弃物和污泥综合利用对控制堆肥质量,提高废弃物综合利用,促进城市节能减排有重要意义。     

几种常用绿地改良材料对土壤水分特征的影响

分析了几种常用绿地土壤改良材料及其不同配比对土壤水分特征曲线和水分常数的影响,结果表明:利用RETC软件对各配比土壤水分特征曲线van Genuchten方程的参数拟合效果较好,R2均大于0.99;随着砂粒含量的增加,土壤田间持水量降低,土壤中水分有效性比例增加,但砂粒粒径对土壤水分常数影响不显著;绿化植物废弃物能提高土壤田间持水量和有效水含量,降低土壤凋萎含水量;绿化植物废弃物还能提高有效水占田间持水量的比例,以20%绿化植物废弃物的用量为最大,为49.59%;聚丙烯酰胺(PAM)虽然能提高土壤田间持水量,但阻碍土壤水分的释放,降低土壤水分的有效性;脱硫石膏可以增加土壤田间持水量和水分的有效性。综合而言,以70%土、10%砂、20%绿化植物废弃物和0.5 kg/m~3脱硫石膏的配比相对最佳。     

不同配比改良材料对典型城市绿地土壤物理性质的影响

选择土壤物理性质退化的典型绿地——上海辰山植物园,进行不同配比改良材料的现场试验,结果显示:与对照相比,不同配比改良材料能显著改善土壤物理性质;并以配比3(土︰绿化植物废弃物︰有机肥=8︰3︰0.8和0.5 kg/m3脱硫石膏)改良效果最好,其土壤体积质量最低,土壤含水量、饱和持水量、田间持水量、非毛管孔隙度、毛管孔隙度和有效水含量最高,土壤饱和导水率也达到良好水平。在30、90和180天的试验时间内,同一配比土壤物理性质较稳定;各配比土壤水分特征曲线均较好拟合Gardner模型(R20.9)。砂虽能增加土壤导水率,但对绿地土壤物理性质改良综合效果不及绿化植物废弃物或草炭等有机材料;而脱硫石膏对土壤各物理性质的改良作用随试验时间延长,其作用越来越明显。在所有改良材料中,以有机材料和脱硫石膏混合使用效果最佳。     

园林废弃物不同处理方式的环境影响及其产物还田效应

针对城市园林废弃物数量日趋增多及资源化利用程度低的问题,该研究比较了园林废弃物在直接焚烧、好氧堆肥、热解碳化3种处理方式下的养分与碳素与氮磷钾损失、温室气体排放,以及相应产物还田对土壤物理化学性质的影响。结果表明,焚烧处理的有机碳损失率高达98.62%,分别比好氧堆肥、碳化处理高39.77%和41.64%;全氮损失率高达95.51%,显著高于好氧堆肥（22.72%）及碳化（36.65%）处理;3种处理全磷及全钾损失率的差异相对较小。焚烧处理的CO2排放量高达1271.62 g/kg,远高于好氧堆肥的210.71 g/kg,但两者CH4、N2O的排放量都相对很小。园林废弃物堆肥及碳化后还田均可促进土壤中小团聚体向大团聚体转化,提高土壤中毛管孔隙度和饱和导水率,并显著提高N、P、K含量;其中生物炭还田可显著提高土壤有机碳含量,好氧堆肥还田能降低土壤pH值。焚烧后的灰分还田除提高土壤P、K养分含量及大粒径团聚体外,其他效果不明显。综上所述,好氧堆肥和碳化是适用于城市园林废弃物处理的2种技术,研究结果可为城市园林废弃物资源优化处理利用提供参考。     

矿化垃圾和绿化植物废弃物在盐碱土上利用的效果

通过矿化垃圾和绿化植物废弃物在盐碱土上的现场应用试验,研究了土壤性质的变化.结果表明,盐碱土上利用矿化垃圾和绿化植物废弃物后pH和盐分降低,土壤肥力提高;但矿化垃圾中有机质相对稳定,而绿化植物废弃物易分解,其土壤微生物量碳、土壤脲酶和土壤磷酸酶增加效果更明显;而且以矿化垃圾、绿化植物废弃物和原土混合后土地利用的效果最好,其次为矿化垃圾和绿化植物废弃物混合,以矿化垃圾和5%原土处理的利用效果最差;而不同废弃物用量中以30%的绿化植物废弃物添加量改良效果最好;不同处理间土壤微生物量碳、土壤脲酶和土壤磷酸酶的变化趋势基本一致,并与有机质存在显著或极显著相关关系,适合评价有机废弃物土地利用的效果.     

半干旱生态系统中生物废弃物对土壤及植物的影响

在半干旱气候条件下,土壤由于水力侵蚀而逐渐退化。把生物废弃物和城市固体废弃物(MSW)以不同比例一次性表施于退化了的半干旱生态系统中的不同地块。以研究施用生物废弃物后,对土壤理化性质和自然植物的影响。最初,土壤N,P,K含量随着生物废弃物施用率的增加而增加,但后期则减少。Zn和Cu的水平MSW处理高于生物废弃物处理。在研究期间,生物废弃物改良的土壤Cd、Pb、Ni和Cr的质量浓度无变化。3a时间里,总植物覆盖度及总植物生物量显著增加,并且所有处理均高于对照。对各处理的自然植物群落发展差异进行观察,3a后施用生物废弃物的处理与未施用的处理差异显著。如果恢复工程的目的是控制侵蚀,应采用高水平施用生物废弃物;若目标是提高物种丰富度,则应采用低水平施入生物废弃物。施用量在40～80t/hm2的生物废弃物时,不存在危害环境的作用。高施用量在明显径流时期则引起P和NO3-N对表面水的潜在有害污染。     

蔬菜废弃物堆肥对设施蔬菜产量和土壤生物特性的影响

采用盆栽试验研究了蔬菜废弃物堆肥对小白菜的增产效果、土壤养分含量、土壤微生物量和酶活性的影响。结果表明,蔬菜废弃物堆肥能够显著提高盆栽小白菜的产量和品质,其中30 t/hm2的高量蔬菜废弃物堆肥将产量提高了66.26%,将品质指标Vc、可溶性糖和可溶性蛋白含量显著提高了35.64%、183.36%和39.42%。蔬菜废弃物堆肥能够显著提高土壤质量,有机质、总氮、碱解氮、有效磷、速效钾含量和土壤微生物量碳、氮,以及土壤淀粉酶、脲酶、磷酸酶、脱氢酶活性的土壤质量指标。与牛粪相比较,高用量的蔬菜废弃物堆肥处理在小白菜产量、可溶性蛋白含量、土壤碱解氮、有效磷、速效钾含量、磷酸酶活性上显著高于牛粪;而在可溶性糖含量、土壤有机质含量、土壤微生物量、淀粉酶、脱氢酶活性上显著低于牛粪。综合而言,蔬菜废弃物堆肥能够提高土壤质量,增加蔬菜产量和品质;在蔬菜产量方面,蔬菜废弃物堆肥优于牛粪,在蔬菜品质和土壤质量方面,蔬菜废弃物堆肥与牛粪相当。     

两种微生物菌剂对烟草废弃物高温堆肥腐熟进程的影响

以烟草废弃物为主要原料,添加合适比例猪粪进行高温堆肥试验,研究了烟草废弃物堆肥体系中加入两种微生物菌剂（NNY、FB）后的温度、总氮（T-N）、NH4＋-N、C/N、种子发芽指数（GI）的动态变化及其对烟草废弃物堆肥产品品质的影响。结果表明,添加微生物菌剂缩短了烟草废弃物堆肥达到高温的时间,延长了高温分解持续时间,增加全氮含量,加快物料NH4＋-N和C/N比的降低速率,提高种子发芽指数（GI）,加快了烟草废弃物堆肥腐熟化进程。纯烟草废弃物单独堆肥,最高温度为43℃,GI最高为78.4%。添加微生物菌剂NNY、FB的堆肥处理都在堆肥2d后进入高温分解阶段（〉50℃）,高温持续时间分别为15、12d,较仅添加合适猪粪比例处理进入高温分解阶段时间提前2d,高温持续时间分别延长5、2d。至堆肥11d,添加微生物菌剂NNY和FB的堆肥处理种子发芽指数较纯烟草废弃物处理分别增加了185.5%和117.7%,较仅添加合适比例猪粪处理分别增加了41.4%和7.6%。添加NNY、FB微生物菌剂的处理可以显著增加烟草废弃物堆肥产品的N、P、K养分含量,降低堆肥容重,提高堆肥总孔隙度和持水孔隙度,改善了堆肥产品的品质。两种微生物菌剂对烟草废弃物高温腐熟效果较优。     

黄土高原退耕还草土壤水分对植物地上部化学计量特征的影响

揭示土壤水分含量变化对植物养分吸收的影响,对阐明草本植被对环境变化的响应和适应性具有重要意义,可为黄土高原区生态治理提供理论依据。研究以安塞纸坊沟流域不同退耕还草年限(6 a,15 a,25 a和45 a)的草本植物和0—50 cm深度土壤样品为研究对象,测定了植物地上部C,N,P,K,Ca和Mg含量及土壤含水率,并分析了植物养分含量及其生态化学计量与土壤含水率的关系。结果表明:土壤含水率随退耕还草过程呈先增加后降低趋势。植物体中C,N,K,Ca和Mg含量整体上随着退耕年限延长先降低后升高,植物P含量在退耕还草初期下降,中后期保持稳定。植物C/N,C/P和N/P比值随退耕年限呈先升高后降低的趋势,并且在退耕还草过程中植物生长主要受到N限制。植物Ca和Mg含量与土壤含水率呈显著负相关。另外,退耕45 a含水率最低,植物C/Ca,C/Mg,N/Ca,N/Mg,P/K,P/Ca,P/Mg比值也是最低的,表明植物可以增加吸收K,Ca和Mg以应对水分胁迫。研究表明土壤含水率随退耕还草过程降低,土壤水分降低促进干旱半干旱地区植被对环境的适应。研究结果为改善干旱半干旱区植被生态稳定性提供科学依据。     

常用绿地土壤改良材料对土壤水分入渗的影响

利用一维垂直土柱法研究几种常用的绿地土壤改良材料及其不同配比对土壤水分入渗的影响,结果表明:土壤水分稳定入渗率、累积入渗量和湿润峰下移距离随土壤含砂量和粒径的增加而显著增加;绿化植物废弃物能提高土壤入渗及湿润峰下降深度,但单独应用效果不明显;脱硫石膏增加土壤入渗,加快湿润峰下移速度;但表施聚丙烯酰胺阻碍土壤水分下渗。Kostiakov入渗模型(I=Kt~(1-α))及幂函数(F=at~b)分别能很好地拟合几种改良材料的累积入渗量以及湿润峰随时间的变化,拟合系数R~2均在0.99以上,且模型中各项指标均较好地表征了几种改良材料的初始累积入渗量、土壤入渗能力的衰减程度及湿润峰变化。以体积比70%土+10%砂+20%绿化植物废弃物+0.5kg/m~3脱硫石膏配比对绿地雨水入渗和蓄积能力最佳。     

基于废弃物的潞安煤矿废弃地改良土壤基质配比研究

为解决潞安矿区煤矸石山、塌陷地生态修复缺土少肥问题,本研究将粉煤灰、污泥与垃圾堆肥以5%、10%、20%体积比例正交混合配制改良土壤基质进行盆栽试验,观测不同配比土壤的理化性质、养分及重金属含量、高羊茅与紫叶小檗生长状况,并用主成分–聚类分析法筛选最优配比。结果表明:添加垃圾堆肥可以提高土壤有效养分与有机质含量,对土壤理化性质改良有明显效果;添加污泥仅提升土壤有效磷含量;添加粉煤灰在降低土壤容重、增大总孔隙度与非毛管孔隙度上效果明显,但对土壤p H、阳离子交换量(CEC)与碱解氮的改良具有显著负效应。各废弃物改良基质的碱解氮、有效磷、速效钾、有机质等含量均较高,土壤重金属含量也处在安全范围,而土壤容重、非毛管孔隙、pH、电导率(EC)与CEC等指标性质较优的处理组为粉煤灰∶污泥∶垃圾堆肥∶土=5%∶20%∶20%∶55%、10%∶10%∶20%∶60%、20%∶5%∶20%∶55%3个处理。经过综合筛选,本研究基质最优混合配比为粉煤灰∶污泥∶垃圾堆肥∶土=5%∶20%∶20%∶55%,可作为当地矿区废弃地生态修复客土材料推荐方案。     

Short‐term effect of biochar and compost on soil fertility and water status of a Dystric Cambisol in NE Germany under field conditions

Crop growth in sandy soils is usually limited by plant‐available nutrients and water contents. This study was conducted to determine whether these limiting factors could be improved through applications of compost and biochar. For this purpose, a maize (Zea mays L.) field trial was established at 1 ha area of a Dystric Cambisol in Brandenburg, NE Germany. Five treatments (control, compost, and three biochar‐compost mixtures with constant compost amount (32.5 Mg ha^–1) and increasing biochar amount, ranging from 5–20 Mg ha^–1) were compared. Analyses comprised total organic C (TOC), total N (TN), plant‐available nutrients, and volumetric soil water content for 4 months under field conditions during the growing season 2009. In addition, soil water‐retention characteristics were analyzed on undisturbed soil columns in the laboratory. Total organic‐C content could be increased by a factor of 2.5 from 0.8 to 2% (p < 0.01) at the highest biochar‐compost level compared with control while TN content only slightly increased. Plant‐available Ca, K, P, and Na contents increased by a factor of 2.2, 2.5, 1.2, and 2.8, respectively. With compost addition, the soil pH value significantly increased by up to 0.6 (p < 0.05) and plant‐available soil water retention increased by a factor of 2. Our results clearly demonstrated a synergistic positive effect of compost and biochar mixtures on soil organic‐matter content, nutrients levels, and water‐storage capacity of a sandy soil under field conditions.     

Effect of Municipal Solid Waste Compost on Mine Soils As Evaluated by Chemical,Biological And Biochemical Properties of Soil

Composts are increasingly used in land rehabilitation because they can improve soil quality and reduce the need for inorganic fertilizers. Their use contributes to an integrated approach to waste management by promoting recycling of nutrients and minimizing final disposal of organic residues that, due to their composition, can pose problems to agricultural soils. We investigated whether compost from mixed municipal solid waste (MSW) could be used to remediate two soils from a mine contaminated with trace elements. One of the soils was less acidic and had a greater content of Cu and Zn while the other had more Pb and a lower pH. The effect of MSW was evaluated by plant growth, trace element leachability, ecotoxicity of soil leachates, and biological and biochemical properties of soils. Growth of perennial ryegrass (Lolium perenne L. cv. Victorian) was stimulated in the MSW compost-amended soils compared with respective controls or with acidic soil when limed. After ryegrass had been growing for 119 days, the amount of water-extractable Zn was lower in MSW compost-amended soils, while the opposite was true for water-extractable Cu. Water-extractable Pb increased following MSW compost application to one soil and decreased in the other. The greatest dehydrogenase activity was obtained in amended limed soil, while the number of culturable bacteria and fungi and the activities of cellulase and β-glucosidase were similar in soil that was limed or following MSW compost application. In contrast, urease activity was repressed in limed or MSW compost-amended soils. Leachates from unamended soils were toxic towards Daphnia magna. Liming the very acidic soil led to a decrease in the toxicity of the leachate, but it was only in MSW compost-amended soils that ecotoxicity was no longer detected.     

Long-term effects of compost amendment of soil on functional and structural diversity and microbial activity

We studied the effects of applying different composts (urban organic waste, green waste, manure and sewage sludge), mineral fertilizer and compost plus mineral fertilizer on chemical, biological and soil microbiological parameters over a 12‐year period. The organic C and total N levels in soils were increased by all compost and compost + N treatments. Microbial biomass C was significantly (P ≤ 0.05) increased for some compost treatments. In addition, basal respiration and the metabolic quotient (qCO₂) were significantly higher in all soils that had received sewage sludge compost. The Shannon diversity index (H), based on community level physiological profiling, showed a higher consumption of carbon sources in soils treated with compost and compost + N compared with the control. The utilization of different guilds of carbon sources varied amongst the treatments (compost, compost + N or mineral fertilizer). Cluster analysis of polymerase chain reaction‐denaturing gradient gel electrophoresis patterns showed two major clusters, the first containing the mineral fertilization and compost treatments, and the second, the composts + N treatments. No differences in bacterial community structure could be determined between the different types of compost. However, the results suggest that long‐term compost treatments do have effects on the soil biota. The results indicate that the effects on the qCO₂ may be due to shifts in community composition. In this study, it was not possible to distinguish with certainty between the effects of different composts except for compost derived from sewage sludge.     

Amending a loamy sand with three compost types: impact on soil quality

The objective of this study was to investigate the effects of the long‐term addition of three compost types (vegetable, fruit and yard waste compost – VFYW, garden waste compost – GW and spent mushroom compost – SM) on the physical properties of a sandy soil and to quantify any such effects using indicators of soil physical quality. Soil samples were taken from a field with annual compost applications of 30 m³/ha for 10 yr and various physico‐chemical analyses were undertaken. Results show a significant increase in soil organic carbon (21%) with the VFYW and GW compost types. With SM, soil organic carbon increased by 16%. Increased soil macroporosity and water content at saturation with a corresponding decrease in bulk density were observed for all compost types. However, quantification of these improvements using existing soil physical quality indicators such as the ‘S‐index’, soil air capacity and matrix porosity gave mixed results showing that these indices perform poorly when applied to sandy soils. It is concluded that the long‐term application of compost does not significantly improve the physical properties of sandy soils, but the absence of adverse effects suggests that these soils are a viable disposal option for these composts, but new indices of quality are needed for the proper characterization of sandy soils.     

Potential Compost Benefits for Restoration Of Soils Disturbed by Urban Development

Compost amendment of soils degraded by urban development is seen as a way to improve soil and landscape quality, reduce runoff, and create a high-value market for locally produced compost. This review evaluates literature on organic soil amendments used in agriculture and horticulture, and extends results to disturbed soils in urban landscapes. Research on agricultural use of organic amendments consistently shows soil bulk density and penetration resistance decreasing with increasing amendment rate, and aggregate stability, porosity, and infiltration rate increasing with amendment rate. The effect of organic amendments on plant available water is less clear. Although organic amendments increase soil water holding capacity, much of the increase may not be available to plants. The nutrient benefits of compost amendments are often overlooked. Composts with a C:N ratio of 20:1 or less can provide significant amounts of nitrogen and other nutrients, improving the establishment of turf and landscape plants, and reducing the amount of supplemental nutrients needed. Materials with a high C:N ratio immobilize N, which can retard plant establishment. Results suggest that compost amendment rates of about one-third by volume should be suitable for establishing landscape beds in humid, temperate environments in soils degraded by development. Rates of 15 to 25% by volume are suggested for lawn establishment.     

The Effects of Short-Term Compost Application On Soil Chemical Properties and on Nutritional Status of Maize Plant

Compost may improve the soil quality and contribute to C sequestration. The short-term effects of compost application on soil properties of soil cropped with maize are reported here. Soil plots to which mature compost was added (at 50 Mg ha^?1 and 85 Mg ha^?1) were analyzed for total organic carbon (TOC), nutrients, heavy metals and other soil properties. In addition, maize plants were weighed at the end of the trial and analyzed for carbon (C), nitrogen (N), phosphorus (P) and heavy metals. The results demonstrate that soil amended with compost has an increased TOC content. The increase was proportional to the amount of compost used. At the highest dose used, compost also increased soil N and P content and the pH. Moreover, after compost application, the total heavy metal contents in soils did not increase. There was no difference between the maize yield from compost treated plots and the control plots. However, maize grains were found to be C, N and P enriched due to the increased nutrient status of the amended soil. In conclusion, the addition of mature compost improves soil properties by increasing the soil TOC content and this depends on the characteristics and the amount of compost used.     

Long‐lasting impact of biowaste‐compost application in agriculture on soil‐quality parameters in three different crop‐rotation systems

Soil‐quality parameters, such as soil organic matter (SOM) and plant‐available nutrient contents, microbial properties, aggregate stability, and the amounts of heavy metals were carried out in arable soils of different rotation schedules applied with a total of 50 Mg dry mass ha^–1 biowaste compost relative to an untreated control. This was investigated during a 10 y period from 1994 to 2004. Overall, soil‐quality parameters studied appeared to be promoted by biowaste‐compost application. This was evidenced for example by a remarkable increase of SOM and total N content of ≈ 15%–20% relative to the control. Subsequently, amounts of soil microbial biomass and alkaline phosphatase activity were significantly increased as well. In addition, biowaste‐compost application revealed an increase of plant‐available P and K contents and aggregate stability in soil. There was, however, no treatment effect for net N‐mineralization rates. Moreover, in soils of maize and sugar beet rotation schedule a slight decrease was found. Heavy‐metal contents of Pb and Zn were significantly increased in all compost‐treated soils, whereas no significant increase of Cd and Cu contents was measured. However, the investigated amounts were far below of the limits of the German Biowaste Ordinance. It is finally recommended, that biowaste compost may sustain and improve soil quality in agriculture when N nutrition will be considered.     

Short-term effects of municipal solid waste compost amendments on soil carbon and nitrogen content, some enzyme activities and genetic diversity

Municipal solid waste (MSW) composts have been frequently used as N and C amendments to improve soil quality and to support plant growth, with the additional benefit of reducing waste disposal costs. However, attention has been paid to the risks of MSW use for the soil environment. The presence of heavy metals in MSW composts can affect some microbiological characteristics of soil such as the structure of the soil microbiota, which are responsible for the transformations making nutrients available to plants. The effects of MSW compost and mineral-N amendments in a 2-year field trial on some physical-chemical properties, some enzyme activities and the genetic diversity of cropped plots (sugar beet-wheat rotation) and uncropped plots were investigated. Variations of pH were not statistically related to MSW compost and mineral-N amendments, or to the presence of the crop. Amendment with MSW compost increased the organic C and total N contents, and dehydrogenase and nitrate reductase activities of soil. In cropped plots amended with MSW compost, dehydrogenase activity was positively correlated with #-glucosidase activity, and both enzyme activities with organic C content. No MSW compost dosage effect was detected. No effects were observed on denaturing gradient gel electrophoresis and amplified rDNA restriction analysis patterns, indicating that no significant change in the bacterial community occurred as a consequence of MSW amendment.     

Changes in the microbial activity of an arid soil amended with urban organic wastes

Changes produced in the biological characteristics of an arid soil by the addition of various urban wastes (municipal solid waste, sewage sludge and compost) at different doses, were evaluated during a 360-day incubation experiment. The addition of organic materials to the soil increased the values of biomass carbon, basal respiration, biomass C/total organic C ratio and metabolic quotient (qCO₂), indicating the activation of soil microorganisms. These biological parameters showed a decreasing tendency with time. Nevertheless, their values in amended soils were higher than in control soil, which clearly indicates the improvement of soil biological quality brought about by the organic amendment. This favorable effect on soil biological activity was more noticeable with the addition of fresh wastes (municipal solid waste or sewage sludge) than with compost. In turn, this effect was more permanent when the soil was amended with municipal solid waste than when it was amended with sewage sludge. Received: 28 May 1996