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长期施用沼液对土壤及产品的影响 总被引：4，自引：0，他引：4
文章通过对长期施用沼液的土壤进行采样分析,研究施用沼液对土壤养分和重金属含量、农产品的重金属含量的影响,以期为沼液的安全利用、降低土壤被重金属污染的风险提供参考依据。结果表明,施用鸡粪沼液配合水溶肥料,可以满足作物对氮、磷、钾、有机质的需求,并且可以提高土壤p H值;基地B和C连续8年施用鸡粪沼液,增加了土壤中部分重金属含量和果实中Cr含量,但是都未超过国家相关标准;D地块施用鸡粪沼液50m~3·677m~(-2),土壤中As,Cr,Hg,Cd,Pb都显著高于未施用沼液的A地块,并且土壤中Cd含量超过了《GB 15618-1995土壤环境质量标准》二级土壤中的限定值(为保障农业生产,维护人体健康的土壤限制值)。 相似文献
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沼液作为肥料施用是沼液资源化利用的重要方式,是构建高效沼液循环利用模式的关键。因此,研究沼液施用对土壤质量的影响可为沼液资源化安全利用提供科学依据。本文选取土壤体积质量、土壤养分、土壤酸碱度、土壤酶活性、土壤微生物和土壤重金属6个代表性指标,综述了沼液施用对土壤质量的影响。合理施用沼液有利于降低土壤体积质量,增强土壤养分累积,改善土壤酸碱度及提高土壤酶活性。长期沼液施用可能会导致土壤微生物类型由“细菌型”转向“真菌型”,并带来重金属污染风险。当前的研究难点主要在于沼液的异质性及土壤评价方法不统一,探究沼液最佳施用量、明确土壤沼液最大承载量、沼液影响土壤质量的机理机制、建立统一的土壤质量评价方法是未来的研究重点。 相似文献
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《中国沼气》2018,(6)
为探讨不同沼液施用量对土壤镉的修复效果,文章采用盆栽试验,以中重度Cd污染水稻土为研究对象,探讨了不同量沼液施用下土壤镉形态分布的变化及对水稻镉积累的影响。结果表明:1)施用不同沼液施用量后,土壤中重金属Cd发生变化,含量降低了53.16%,51.57%,48.88%,61.57%,63.16%,说明一定量的沼液施入能减少土壤中的Cd含量;2)施用沼液能改变土壤重金属Cd的存在形态;3)随着沼液量的增加,糙米中Cd含量呈减少的趋势,均小于常规化肥组的Cd含量;4)采用Hakanson的潜在生态风险指数法对种植后土壤的重金属Cd生态风险进行了评价,与原土相比,沼液的施用不会增加土壤的潜在生态风险。综上,与施用化肥相比,在中重度Cd污染的土壤上施加适量沼液能增加土壤养分,降低土壤中的Cd含量,使土壤Cd形态由生物有效性向非生物有效性转化,降低了Cd在水稻中的积累量。 相似文献
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定量分析沼液施用对作物产量和土壤肥力及重金属累积的综合效应，旨在明确等氮沼液对作物产量、土壤肥力参数和重金属累积的影响，为优化沼液施用综合管理措施，发挥沼液施用积极效果提供数据参考。运用Meta分析方法将中英文数据库中已发表有关等氮沼液(BS)和全施化肥(CF)处理对作物和土壤肥力影响文献进行检索筛选，共选出有效文献62篇，获得可进行分析的试验数据591组。研究结果表明：与全化肥处理相比施用沼液作物增产7.62%但差异不显著(p=0.07);土壤容重降低6%、总孔隙度增加14%、较大团聚体含量增加10%～20%,差异显著(p<0.05);土壤有机质、总氮、速效磷、阳离子交换量和电导率增幅6%～20%并导致盐分累积加剧(p<0.05);土壤脲酶、蔗糖酶和磷酸酶活性及微生物碳氮含量、香农指数和辛普森指数增幅6%～21%(p<0.001);土壤Cu、Zn和As含量比全化肥(CF)处理显著增加10%～18%。沼液施用对作物增产和土壤肥力提升显著正效应，需要考虑沼液施用年限、土壤类型、作物种类，严格控制施用量降低盐分和重金属累积风险，实现沼液安全高效利用。 相似文献
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水稻施用沼肥效果分析 总被引：2，自引：0，他引：2
沼渣、沼液作为有机肥对农作物施用,不仅能提高农作物产量,而且提高其品质,改善土壤的团粒结构,减少化肥对土壤的污染.按照要求,在上级有关部门的指导下,近年来我们对沼液肥效进行试验,目的是通过沼渣、沼液的不同施用方法和用量,使作物在每个生育期的表现性状的差异,最终反映在产量上有何不同,找出其规律,从而指导农民搞好综合利用. 相似文献
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中国沼液施用对作物产量效应的Meta分析 总被引：1，自引：0，他引：1
为了探讨在中国地区施用沼液的增产效应,文章综合1999～2017年间已发表的78组田间试验研究数据,应用Meta分析方法定量分析沼液施用在不同条件下对作物产量的效应。结果表明,施用沼液提高作物产量在西北和华北较为明显,西南和华东地区略低;沼液的增产效应不受作物影响,小麦、玉米、番茄和水稻产量均有所提高,增产率分别为15.97%,20.62%,18.02%和12.57%;沼液施用年降雨量≥500 mm和年降雨量<500 mm时均能提高作物产量;较年平均气温<12℃,年平均气温≥12℃时作物增产率更为显著。该研究成果可为沼液在农业中的进一步推广应用提供理论支撑。 相似文献
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沼液与化肥长期配施对蔬菜生产和土壤肥力的影响 总被引：1，自引：0，他引：1
在2009～2011年长期连续5茬蔬菜作物田间试验的基础上,研究测定了番茄和甜椒2种蔬菜的产量、硝酸盐,可溶性固形物,Vc和总酸量,以及土壤的pH,EC,有机质、铵态氮和硝态氮等指标.结果表明,沼液与化肥配施能明显地提高番茄和甜椒的产量,提高蔬菜中Vc含量;无论是沼液与化肥配施还是单独施用沼液,均加剧了表层土壤的酸化和盐渍化,长期使用易导致深层土壤酸化和盐渍化,同时有利于表层土壤的无机氮含量累积,短期内施用对土壤有机质含量影响不大. 相似文献
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针对化探样品批量大,元素多,检出限低等特点,采用水平电极撒料法,对化探样中多种微量元素进行了光谱定量分析.将样品与缓冲剂1:1混匀,采用W-100光栅摄谱仪(光栅刻线1200条/毫米,二级光谱)进行水平撒样摄谱,谱板经暗室处理后,在东德GFE760μ测微光度计上用P标尺测光,以△P-logc绘制工作曲线,查出含量.本法采用了特制的撒样漏斗,改善了下料的均匀性,提高了分析精度;以Ge和Pd作内标消除工作条件变化对谱线强度的影响;同时还试选了SiO2:C:Na2SO4＝61:30:9的混合物作缓冲剂,提高了弧烧的稳定性,获得了较高的再现性.本文还采用了一种单元素线减光器对Ag3382.9进行减光,使Ag的测定上限由5×10-6提高到30×10-6.本法操作简便快速,成本较低,一次可测定Ag、W、Mo、Sn、Bi、Cu、Pb、Zn、Ni、Co、Cr等多种元素,检出限为Ag 0.03×10-6,W 0.5×10-6,Mo0.05×10-6,Sn 0.4×10-6,Pb 1×10-6,Zn 3×10-6,Cu 0.5×10-6,Bi 0.1×10-6,Ni 0.3×10-6,Co 0.3×10-6,Cr 1×10-6,基本上达到了化探普查找矿定量分析的要求. 相似文献
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当前,中国粮油企业的生存与发展已与世界粮油经济的发展息息相关。无论是粮油企业全面亏损的2004年,还是粮油价格大起大落的2008年,世界其他各国粮油政策和价格的变化均对中国的粮油产业发展造成了很大的影响。全面了解国际粮油发展新动向、掌握世界粮油食品发展新方向,从宏观上为企业找到准确定位,是每位粮油企业家、每位粮油人都必须具备的。正所谓知己知彼,百战不殆,希望以下这些国际前沿信息能为您带来收获。 相似文献
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为了快速、准确地检测土壤中多种重金属元素,建立一种王水消解同时测定土壤中Cu,Zn,Ni,Cr,Pb,Cd的方法.选取8种具有广泛代表性的土壤标准物质对王水消解法进行考察,结合土壤标准物质标准值,通过大量试验数据对该方法做出全面评价. 相似文献
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砀山县丰产农机服务专业合作社位于安徽省宿州市砀山县朱楼镇朱楼村,成立于2015年5月13日。合作社目前占地1.33 hm^2(20余亩),拥有成员200余人,拖拉机40多台,收割机18台,灌溉机械14套,植保飞机80多架,烘干机6组,配套农具230多台(套),机械资产达到1 200余万元。 相似文献
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J. R. Philip 《Irrigation Science》1987,8(2):101-114
Summary We study the effect of surface resistance r (whether of monolayers on free water or plant diffusive resistance) on evaporation rate, energy balance, and microclimate, under advective conditions. We use power-law representations of the vertical profiles of mean windspeed and eddy diffusivity, and exploit two known similarity solutions, one for a step-function change of surface concentration, and the other for a step-function change of surface flux density. To a very close approximation, these two contrasting canonical advective problems yield the same (spatially variable) boundary layer transfer coefficient expressing the ratio of the surface flux perturbation to the surface concentration perturbation. Adopting this coefficient reduces the (spatially variable) surface energy balance for the advective boundary layer with surface resistance to a quadratic equation, with the solution yielding the fetch distances x at which the surface temperature assumes a given value To. With To (x) established thus, the other significant properties of the boundary layer follow simply and directly.The results reveal the profound influence of r, especially at small x. As boundary layer atmospheric resistance increases with x, r becomes relatively less important. It can be regarded as primarily reducing advective effects. Antievaporation films thus work best on small water surfaces in arid surroundings, but are less effective the larger the water body and the moister the surrounds. If leaf temperatures are not limiting, increasing r has greatest effect for small vegetated areas in an arid environment, but may not be optimal for extensive continuous monocultures. Control of surface resistance offers means of manipulating microclimate, for example when arid landscapes are watered for this purpose. The exploratory nature of this investigation, and its many limitations, are stressed. 相似文献
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E. Owen 《Agricultural Systems》1983,11(1):66
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《Agricultural Systems》2002,74(1):141-177
FARMSCAPE (Farmers', Advisers', Researchers', Monitoring, Simulation, Communication And Performance Evaluation) is a program of participatory research with the farming community of northeast Australia. It initially involved research to explore whether farmers and their advisers could gain benefit from tools such as soil characterisation and sampling, climate forecasts and, in particular, simulation modelling. Its current focus is facilitating the implementation of commercial delivery systems for these same tools in order to meet industry demand for their access. This paper presents the story of what was done over the past decade, it provides performance indicators of impact, it reflects on what was learnt over this period and it outlines where this research is likely to head in the future.Over the past 10 years, the FARMSCAPE team employed a Participatory Action Research approach to explore whether farmers could value simulation as a decision support tool for managing their farming system and if so, could it be delivered cost-effectively. Through farmer group engagement, on-farm trials, soil characterisation, monitoring of crops, soils and climate, and sessions to apply the APSIM systems simulator, FARMSCAPE represented a research program on decision support intervention. Initial scepticism by farmers and commercial consultants about the value of APSIM was addressed by testing its performance both against measured data from on-farm trials and against farmers' experiences with past commercial crops. Once this credibility check was passed, simulation sessions usually evolved into participants interactively inquiring of the model the consequence of alternative management options. These ‘What if’ questions using APSIM were contextualised using local climate and soil data and the farmer's actual or proposed management rules.The active participation of farmers and their advisers, and working in the context of their own farming operations, were the key ingredients in the design, implementation and interpretation of the FARMSCAPE approach to decision support. The attraction of the APSIM systems simulator to farmers contemplating change was that it allowed them to explore their own system in a manner equivalent to learning from experience. To achieve this, APSIM had to be credible and flexible. While direct engagement of farmers initially enabled only a limited number of beneficiaries, this approach generated a commercial market for timely and high quality interactions based on soil monitoring and simulation amongst a significant sector of the farming community. Current efforts are therefore focused on the training, support and accreditation of commercial agronomists in the application of the FARMSCAPE approach and tools.The FARMSCAPE approach to decision support has come to represent an approach to guiding science-based engagement with farm decision making which is being tested nationally and internationally. 相似文献