Effects of Increasing Dosages of Acid Mining Wastes in Metal Uptake by Lygeum spartum and Soil Metal Extractability     

Conesa  Héctor M.  Moradi  Ahmad B.  Robinson  Brett H.  Jiménez-Cárceles  Francisco J.  Schulin  Rainer 《Water, air, and soil pollution》2009,201(1-4):379-388

Water, Air, & Soil Pollution - A yearlong (December 2003 to February 2005) monitoring program was undertaken for urban roadside measurement of benzene, toluene, ethyl benzene, m- and p-xylene,...  相似文献   

Spatial patterns of soil biological and physical properties in a ridge tilled and a ploughed Luvisol     

Evelyn Müller  Holger Wildhagen  Michael Quintern  Jürgen Heß  Florian Wichern  Rainer Georg Joergensen 《Soil & Tillage Research》2009,105(1):88-95

The present study was conducted to determine the spatial heterogeneity of bulk density, soil moisture, inorganic N, microbial biomass C, and microbial biomass N in the ridge tillage system of Turiel compared to conventional mouldboard ploughing on three sampling dates in May, July, and August. The soil sampling was carried out under vegetation representing the ridge in a high spatial resolution down the soil profile. Bulk density increased with depth and ranged from 1.3 g cm⁻³ at 10 cm depth to 1.6 g cm⁻³ at 35 cm in ploughed plots and from 1.0 g m⁻³ at 5 cm to 1.4 g m⁻³ at 35 cm in the ridges. In the ploughed plots, the contents of microbial biomass C and microbial biomass N remained roughly constant at 215 and 33 μg g⁻¹ soil, respectively, throughout the experimental period. The microbial biomass C/N ratio varied in a small range around 6.4. In the ridged plots, the contents of microbial biomass C and microbial biomass N were 5% and 6% higher compared to the ploughed plots. Highest microbial biomass C contents of roughly 300 μg g⁻¹ soil were always measured in the crowns in July. The lowest contents of microbial biomass C of 85–137 μg g⁻¹ soil were measured in the furrows. The ridges showed strong spatial heterogeneity in bulk density, soil water content, inorganic nitrogen and microbial biomass.  相似文献   

Comparison of critical limits for crop plant growth based on different indicators for the state of soil compaction     

Manfred Kaufmann  Silvia Tobias  Rainer Schulin 《植物养料与土壤学杂志》2010,173(4):573-583

Soil compaction affects physical soil condition, in particular aeration, soil strength, and water availability and has adverse effects on plant growth. Bulk density is the most frequently used indicator to describe the state of compaction of a soil. However, this parameter lacks a direct functional relationship with plant growth. Various indicators have been proposed to simultaneously characterize the state of compaction of agricultural soil and its suitability for plant growth. This paper examines and compares the critical limits for crop plant growth based on three of these indicators: packing density, least limiting water range, and S parameter (the latter is the slope of the soil water‐retention curve in the inflexion point). In a first step, we reviewed the literature for published optimum and limiting values of bulk density and found that these values were highly dependent on clay and silt content. Converting them into corresponding values of packing density (composite index of bulk density and clay content), a value of 1.70 was found to effectively distinguish between optimum and limiting soil conditions for plant growth. In a second step, the packing density of 59 soil horizons sampled in N Switzerland was compared with the least limiting water range and the S parameter of these soil horizons (both determined by means of pedotransfer functions taken from the literature). A linear relationship between the three parameters was found, which allowed for a comparison of the published critical limits for plant growth based on these parameters. The critical limits of the three indicators, which had been postulated independently of each other in the literature, were found to agree well with each other. This means that all of them could equally be used to describe the compaction state of a soil and its physical suitability for plant growth. However, the proposed critical limits of packing density, least limiting water range, and S parameter still need further validation by field studies relating plant growth to soil compaction.  相似文献   

15N标记氮在盆栽山毛榉中的分配     

Ali Bagherzadeh  Rainer Brumme  Friedrich Beese 《林业研究》2009,20(4):314-322

温室条件下,向盆栽山毛榉幼苗中施加192g.m·^-2^15N示踪物,研究连续两个生长季沉积氮在森林土壤（含森林地被物）、沥出物、以及地上和地下部分生物量的分配。模拟了四种处理（栽培和非栽培）下的NH4^＋和NO3^-沉积情况,每种处理各自标记为^15N-NH4^＋或者^15N-NO3^-。在整个体系中施加15N的总回收率分别是,盆栽处理的^15N-NH4^＋为67.3%～74.9%,非盆栽处理的^15N-NO3^-为85.3%～88.1%。两种^15N示踪物主要沉积在森林土壤（包括森林地被物）中,其中盆栽处理的森里土壤中^15N-NH4^＋为34.6%～33.7%,^15N-NO3^-为13.1%～9.0%,说明异养微生物有很强的固氮作用。森林土壤微生物对^15N-NH4^＋的固定能力比^15N-NO3^-的固定能力强三倍。^15N-NH4^＋的优先异养利用造成土壤中^15N-NH4^＋的沉积量是植物体保存量的两倍 而土壤中^15N-NO3^-的沉积量却低于植物体的。总之,植被-土壤系统中15N-NH4＋的沉积量比^15N-NO3^-的沉积高了60%,说明了沉积氮的形式在森林生态系统中氮保存中的重要性。  相似文献   

Effects of atmospheric and climate change at the timberline of the Central European Alps   总被引：1，自引：0，他引：1  

Gerhard Wieser  Rainer Matyssek  Roland Luzian  Peter Zwerger  Peter Pindur  Walter Oberhuber  Andreas Gruber 《Annals of Forest Science》2009,66(4):402-402

? This review considers potential effects of atmospheric change and climate warming within the timberline ecotone of the Central European Alps. After focusing on the impacts of ozone (O₃) and rising atmospheric CO₂ concentration, effects of climate warming on the carbon and water balance of timberline trees and forests will be outlined towards conclusions about changes in tree growth and treeline dynamics.

? Presently, ambient ground-level O₃ concentrations do not exert crucial stress on adult conifers at the timberline of the Central European Alps. In response to elevated atmospheric CO₂ Larix decidua showed growth increase, whereas no such response was found in Pinus uncinata. Overall climate warming appears as the factor responsible for the observed growth stimulation of timberline trees.

? Increased seedling re-establishment in the Central European Alps however, resulted from invasion into potential habitats rather than upward migration due to climate change, although seedlings will only reach tree size upon successful coupling with the atmosphere and thus loosing the beneficial microclimate of low stature vegetation.

? In conclusion, future climate extremes are more likely than the gradual temperature increase to control treeline dynamics in the Central European Alps.

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Nutritional effects triggered by the extreme summer 2003 in the free air ozone fumigation experiment at the Kranzberger Forst     

A. Göttlein  H. Rodenkirchen  K. H. Häberle  R. Matyssek 《European Journal of Forest Research》2009,128(2):129-134

Since the year 2000 mature beech and spruce trees were treated in a field experiment with double ambient ozone concentrations. Elevated ozone had no influence on average single leaf biomass and there were also no ozone effects on leaf nutrient concentrations in climatic normal years. However, the extraordinary dry summer 2003 triggered significant differences between the fumigated and control trees. For beech in the year after the drought event the control trees surprisingly had significantly lower foliar levels of K and P than in former years, whereas the ozone exposed trees showed no significant nutritional effects. There are indications, that the trees exposed to double ambient ozone were already adapted to higher ozone values, whereas the control trees experienced extraordinary high ambient ozone concentrations in the dry and sunny summer 2003. For spruce in autumn 2003 and 2004 ozone treated trees had significantly higher foliar levels of K in current year needles than control trees, an effect which cannot be thoroughly interpreted yet on the basis of the dataset available. This article belongs to the special issue „Growth and defence of Norway spruce and European beech in pure and mixed stands“.  相似文献   

The potential of coumatetralyl enhanced by cholecalciferol in the control of anticoagulant‐resistant Norway rats (Rattus norvegicus)          下载免费PDF全文

Stefan Endepols  Nicole Klemann  Dania Richter  Franz‐Rainer Matuschka 《Pest management science》2017,73(2):280-286

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Longtime effects of deep groundwater extraction management on water table levels in surface aquifers     

Iris Zimmermann  Heiner Fleige  Rainer Horn 《Journal of Soils and Sediments》2017,17(1):133-143

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生物炭引起的土体回弹变化：土壤质地和生物炭用量的影响     

Ayodele Ebenezer AJAYI  Rainer HORN 《土壤圈》2017,27(2):236-247

Biochars are,amongst other available amendment materials,considered as an attractive tool in agriculture for carbon sequestration and improvement of soil functions.The latter is widely discussed as a consequence of improved physical quality of the amended soil.However,the mechanisms for this improvement are still poorly understood.This study investigated the effect of woodchip biochar amendment on micro-structural development,micro-and macro-structural stability,and resilience of two differently textured soils,fine sand (FS) and sandy loam (SL).Test substrates were prepared by adding 50 or 100 g kg-1 biochar to FS or SL.Total porosity and plant available water were significantly increased in both soils.Moreover,compressive strength of the aggregates was significantly decreased when biochar amount was doubled.Mechanical resilience of the aggregates at both micro-and macro-scale was improved in the biochar-amended soils,impacting the cohesion and compressive behavior.A combination of these effects will result in an improved pore structure and aeration.Consequently,the physicochemical environment for plants and microbes is improved.Furthermore,the improved stability properties will result in better capacity of the biochar-amended soil to recover from the myriad of mechanical stresses imposed under arable systems,including vehicle traffic,to the weight of overburden soil.However,it was noted that doubling the amendment rate did not in any case offer any remarkable additional improvement in these properties,suggesting a further need to investigate the optimal amendment rate.  相似文献   

Revisiting safe biological limits in fisheries          下载免费PDF全文

Rainer Froese  Gianpaolo Coro  Kristin Kleisner  Nazli Demirel 《Fish and Fisheries》2016,17(1):193-209

The appropriateness of three official fisheries management reference points used in the north‐east Atlantic was investigated: (i) the smallest stock size that is still within safe biological limits (SSB_pa), (ii) the maximum sustainable rate of exploitation (F_msy) and (iii) the age at first capture. As for (i), in 45% of the examined stocks, the official value for SSB_pa was below the consensus estimates determined from three different methods. With respect to (ii), the official estimates of F_msy exceeded natural mortality M in 76% of the stocks, although M is widely regarded as natural upper limit for F_msy. And regarding (iii), the age at first capture was below the age at maturity in 74% of the stocks. No official estimates of the stock size (SSB_msy) that can produce the maximum sustainable yield (MSY) are available for the north‐east Atlantic. An analysis of stocks from other areas confirmed that twice SSB_pa provides a reasonable preliminary estimate. Comparing stock sizes in 2013 against this proxy showed that 88% were below the level that can produce MSY. Also, 52% of the stocks were outside of safe biological limits, and 12% were severely depleted. Fishing mortality in 2013 exceeded natural mortality in 73% of the stocks, including those that were severely depleted. These results point to the urgent need to re‐assess fisheries reference points in the north‐east Atlantic and to implement the regulations of the new European Common Fisheries Policy regarding sustainable fishing pressure, healthy stock sizes and adult age/size at first capture.  相似文献