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741.
J. Bone D. Barraclough P. Eggleton M. Head D. T. Jones N. Voulvoulis 《Land Degradation u0026amp; Development》2014,25(3):251-266
Emergence of policies dealing with concern over soil degradation and anthropogenic impacts to soil is likely to increase the requirement for assessment of soil quality and identification of soils at risk from degradation. An example is the proposed EU Soil Framework Directive, which features the identification of areas requiring protection from soil degradation. There have been some serious objections to such requirements on the grounds of resource and capital demands. To help to address these concerns, this work proposes a strategic set of indicators based on measured soil quality indicators. These can be used in screening locations to assess the likelihood of degradation and indicate areas for further detailed assessment. This will allow further emphasis to be placed on a smaller number of locations, which could lead to cost and resource efficiencies. Indicators have been used in the past in assessment of soil quality; they are parameters which can be measured and correspond to assessment criteria to measure and help monitor the status and changes. The study reviews the current state of soil quality assessment including methods and indicators that are used to collect data and approaches used to assess data to determine areas subject to soil degradation. Methods and practicalities for data collection and screening are discussed, including the need for further pilot testing and protocol development. Use of public data collection could allow more resource efficient protection of soils, in addition to benefits of public engagement, and raising awareness of the importance of soils and soil biodiversity. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
742.
本研究对红壤荒坡种草后的土壤微生物区系和土壤酶活性进行了年间、季节间与坡面分布的动态分析.研究表明,荒坡种草后所进行的土壤生物学过程逐年增强,为红壤荒坡种草提供了初步的实践依据。 相似文献
743.
Surajit Mondal Debashis Chakraborty Kalikinkar Bandyopadhyay Pramila Aggarwal Dharamvir Singh Rana 《Land Degradation u0026amp; Development》2020,31(5):557-567
Food security involves the sustainable utilization of soil and land resources. Zero‐tillage (ZT) practice is a proponent of better resource utilization, to improve soil physical condition, and a potential sink to atmospheric carbon. However, the impact varies across climates, over the ZT history, cropping systems, and soil depths. A meta‐analysis was performed, based on 4,131 paired data from 522 studies spread globally, to evaluate the effect of ZT in comparison to conventional tillage, on soil physical condition (bulk density; mean weight diameter of aggregates; field capacity water content; and steady‐state infiltration rate), soil organic carbon (SOC) content, and the root response (root length density). Zero‐tillage significantly improved mean weight diameter of aggregates and field capacity water content at surface and subsurface layers by 19–58% and 6–16%, respectively, and resulted in no change in bulk density in either of the layers, but infiltration rate increased by 66%. Surface 0‐ to 5‐ and 5‐ to 10‐cm layers had significantly higher SOC content under ZT, whereas in other layers, the SOC content either reduced or did not change, resulting in a small and insignificant variation in the SOC stock (~1.1%) in favor of ZT. The root length density improved by ~35% in ZT only at 0‐ to 5‐cm soil depth. Effect of climate, soil type, or cropping system could not be broadly recognized, but the impact of ZT certainly increased over time. Improvements in soil aggregation and hydraulic properties are highly convincing with the adoption of ZT, and therefore, this practice leads to the better and sustainable use of soil resources. 相似文献
744.
玫瑰的营养水平及其土壤环境 总被引：4，自引：1，他引：4
本文对平阴玫瑰的叶片营养水平、生长状况及其土壤条件进行测定。结果表明生长状况不同的玫瑰植株叶片中磷和钙的含量差异明显,其它元素差别甚小,但养分含量之间的比率表现不同。土壤的物理性质,尤其是粗砂、石砾的含量、土壤容重和土壤孔隙状况,可能是影响玫瑰根系生民和产花量的重要原因。文中将平阴玫瑰产地的立地环境与保加利亚玫瑰产地相比较,拟为开发玫瑰选择适宜条件提供参考。 相似文献
745.
Although Ni has been officially recognized as an essential micronutrient for all higher plants since 2004, research on assessing its sufficiency critical levels with different soil tests is missing in the literature. The objective of the study was to determine Ni critical levels in unpolluted cultivated soils utilizing four methods, employing three commonly used calibration techniques. Ten soils with different physical–chemical properties and low Ni content were treated with Ni at rates of 1, 2, 4, and 8 mg kg?1. After equilibration for one month, the soils were analyzed for extractable Ni by four methods, namely DTPA, AB‐DTPA, AAAc‐EDTA, and Mehlich‐3. Response to soil‐applied Ni was assessed by a greenhouse pot experiment, with the untreated and Ni‐treated soils in three replications, using ryegrass (Lolium perenne L.). The aboveground biomass of ryegrass was harvested two months after sowing, dry weight of biomass was measured and relative biomass yield was calculated. Nickel's critical levels were determined employing the: (a) graphical technique of Brown and co‐workers, (b) Mitscherlich–Bray equation, and (c) Cate and Nelson graphical technique. According to the first technique, Ni critical levels were ≈ 2 mg kg?1 for the DTPA and AB‐DTPA methods, and 6.0 and 5.3 mg kg?1 for the AAAc‐EDTA and Mehlich‐3 methods, respectively. Similar levels were obtained by the Mitscherlich–Bray equation. However, the critical levels assessed by the Cate and Nelson technique were lower and ranged from 0.5 to 1.3 mg kg?1 for all four methods. Conclusively, Ni sufficiency critical levels for all four methods are expected to range at levels of a few mg Ni kg?1 of soil. As far as the three calibration techniques are concerned, a distinct boundary between Ni response and non‐response was accomplished by none. However, the fact that 60–74% of the soils were correctly separated into responsive and non‐responsive to added Ni by the graphical technique of Brown and co‐workers suggests that this is the most suitable technique. 相似文献
746.
目前,在我国一些地区,由于不合理的人为社会经济活动作用和影响,新的水土流失正在日益加剧。山东省栖霞县通过调查研究,根据本县实际情况,对防治新的水土流失问题,采取了一系列措施,包括组织、法制、经济等措施。尤其是认真执行了“谁造成水土流失谁治理,谁造成危害谁赔偿”的原则,规定了赔偿费征收的范围和标准。上述综合防治措施,在栖霞县经过几年的实践,收到了较好的效果。 相似文献
747.
YuanPeng Wang QingBiao Li JiYan Shi Qi Lin XinCai Chen Weixiang Wu YingXu Chen 《Soil biology & biochemistry》2008,40(5):1167-1177
Soil microorganisms may play an important role in the uptake of heavy metals from soils. However, assessments of bacterial activity and community composition in the rhizosphere of accumulators have been largely ignored. We studied potential effects of a copper (Cu)-accumulator, Elsholtzia splendens, and a non-Cu-accumulator plant, Trifolium repens, on soil microbial activity and community composition with increasing Cu addition. The results showed that concentrations of Cu in the shoots of E. splendens were 2.1, 2.2 and 2.4 times those of T. repens under the treatment of different Cu concentrations. Soil microbial biomass and phosphatase activity in the rhizosphere of E. splendens were higher than those of T.repens. PCR-denaturing gradient gel electrophoresis (PCR-DGGE) fingerprint analysis revealed that addition of Cu decreased the number of bands in bare soil and soil with T. repens. However, there was a significant increase in the number of bands in soil with E. splendens incorporated with either 200 or 500 mg kg−1 Cu. The abundances of five phylogenetic groups related most closely to -, β-, γ-proteobacteria, Gram-positive bacteria and CFB group, respectively, were determined in the rhizosphere of plants. Some specific clone such as E13 (metal-contaminated soil clone K20-64) was found in the rhizosphere of E. splendens. Results indicated that E. splendens, as a Cu-accumulator, played an important role in governing soil microbial activity and bacterial community composition in the rhizosphere in response to Cu stress. 相似文献
748.
在对浙东沿海某典型固废拆解区的水-土壤-农作物系统进行系统调查和分析的基础上,重点探讨了污水灌溉对土壤多氯联苯（PCBs）含量的影响程度,并通过建立数学模型,对污灌区土壤PCBs含量进行了预测。结果表明,研究区土壤、水体、底泥乃至农作物均检测出相当水平的PCBs,对当地的生态安全影响较大;经因子分析和对比分析发现,约有67.3%的土壤PCBs污染是由污水灌溉引起,污水灌溉对土壤污染的影响显著;在现有农田灌溉模式不变的情况下,污灌区的土壤PCBs含量将呈上升趋势,50a后含量将增加1倍。 相似文献
749.
《Land Degradation u0026amp; Development》2018,29(4):1074-1080
The mudflats along the east coast of China can be important alternative sources for arable lands after amendment. The newly reclaimed mudflats as typical saline soils are not suitable for cultivation owing to high salinity and nutrient deficiencies. The key to amending mudflat saline soils into fertile soils is to reduce salinity in the top layer of soil. Salinity reduction is usually accomplished through rainfall and freshwater irrigation. However, lack of good soil aggregation status might attribute to salt solution rise through soil capillary. Increasing soil organic matter promoted the formation of organo‐mineral complexes and clustered soil aggregates, which is a prerequisite of hindering re‐salinization, improving fertility and facilitating the evolution of coastal mudflat soil into agricultural soil. Research on the formation of clustered soil aggregates during the evolution of mudflat soil into fertile soil should focus on the formation mechanism, influencing factors and regulatory mechanism of organo‐mineral complexes in the early stage after organic matter enters the soil. In addition, exploration of the effects of the special properties of mudflat soil, for example, high saline, high pH and low levels of clay particles, on the formation and stability of organo‐mineral complexes in soil is necessary. Research on this topic can provide scientific evidences to efficiently utilize organic resources and accelerate the evolution of mudflat soil into agricultural soil. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
750.
Rainer Horn Catalin Simota Heiner Fleige Anthony Dexter Kalman Rajkai Diego de la Rosa 《植物养料与土壤学杂志》2002,165(2):235-239
Prediction of soil strength of arable soils and stress dependent changes in ecological properties based on soil maps Based on a database of at present 160 mechanical soil profile datasets, the site and horizon dependent mechanical soil strength expressed as precompression stress can be predicted by multiple regression analysis and used for documentation in maps at different scales. Stress dependent changes in air permeability or air capacity can be derived for the virgin compression stress range as well as the effect of stress propagation in soils or stress attenuation capacity and depth dependent changes of ecological properties. Thus, areas with defined mechanical sensitivity as a function of depth can be derived and recommendations for site adjusted farming techniques can be given. In addition it allows the agricultural machine industry to develop site adjusted machines to support the ideas of good farming practice, defined by the soil protection law of Germany. 相似文献