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Ecological Processes 2023年第1期12卷 100-111页

作者： Friederike Sieve Johannes Isselstein manfred kayser Department of Crop Science Grassland Science Georg-August University G?ttingen Geo-Lab University of Vechta

Background Public interest in the way food is produced on the farm and processed along the food-production chain is increasing. The analysis of isotopic signatures(13C) in cow tail hair provides a method to reconstruct the dietary proportion of maize in cow diets. Based on this, we further investigated whether there is a relationship between isotopic signatures in cow tail hair or farm slurry and the proportion of maize of the total utilized agricultural area per farm [%]. We did an on-farm survey on 17 dairy farms in coastal Northwest Germany and collected cow tail hair from dairy cows and slurry samples on each farm. The farms differed in their feeding regime（C3vs. C4plants）, their site conditions（sandy soil = ‘Geestland'; organic soil = ‘Peatland'; clayey soil = ‘Marshland'）, and in the area cultivated with maize as a proportion of the total utilized agricultural area per *** We found a positive relationship between δ13C values in both cow tail hair and slurry and the annual dietary proportion of maize（R2= 0.67; and R2= 0.63）. Furthermore, we confirmed that there was a relationship between δ13C values in cow tail hair and area of maize as a proportion of the total utilized agricultural area per farm（R2= 0.69）.Conclusion Our findings suggest a general applicability of using isotopic signatures(13C) along a wide gradient of site conditions and productions systems in practice.

关键词： Stable isotopes Natural 13 C abundance Environmental indicator Maize Dietary composition Traceability

林牧系统的树木中豆科植物的比例减少并不影响其内部的氮吸收效率

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Journal of Plant Ecology 2023年第3期16卷 40-53页

作者： Andrea Schmiedgen Martin Komainda manfred kayser Bettina Tonn Johannes Isselstein Grassland Science Department of Crop SciencesGeorg-August-University GöttingenD-37075 GöttingenGermany Centre of Biodiversity&Sustainable Land Use D-37077 GöttingenGermany Geo-Lab University of VechtaD-49377 VechtaGermany Department of Livestock Sciences FiBLCH-5070 FrickSwitzerland

在以豆科植物为主的草地中,豆科植物通过生物固氮为草地提供氮(N)。以往对林牧系统的研究发现,树木附近的豆科植物比例下降,将导致N供应以及树间草坪收获的牧草中N浓度的空间变化。在自然生态系统中,氮吸收效率(NRE)随着养分限制而增加... 详细信息

在以豆科植物为主的草地中,豆科植物通过生物固氮为草地提供氮(N)。以往对林牧系统的研究发现,树木附近的豆科植物比例下降,将导致N供应以及树间草坪收获的牧草中N浓度的空间变化。在自然生态系统中,氮吸收效率(NRE)随着养分限制而增加,所以在树木附近豆科植物比较稀缺。本研究验证了以下假设,即树木附近的NRE增加,补偿了豆科植物相对于牧草中N浓度的损失。为此,本研究分析了5年前建立的巷道种植系统中,分布在林木间的两种由豆科草本植物为主的植被组成。研究结果表明,豆科植物的比例向树线方向下降了45%,因此,活的和枯死的牧草中的N浓度也下降了,但平均仅下降了15%。由于N浓度降低以及靠近树木的牧草质量下降,N产量最多下降了50%。尽管树木附近的豆科植物减少,但无论植被组成如何,NRE都不受树线的影响。此外,与未管理的生态系统相比,收获之间的落叶间隔较短的林牧草地中管理草坪的内部N循环的相关性较低。豆科植物的比例控制着活的和枯死的草本植物的N浓度,而与林牧系统中的树木遮阴无关。

关键词：农林业氮循环草地管理豆科植物

A soil quality index for subtropical sandy soils under different Eucalyptus harvest residue managements

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Journal of Forestry Research 2023年第1期34卷 243-255页

作者： Jackson Freitas Brilhante de Sao José Maurício Roberto Cherubin Luciano kayser Vargas Bruno Brito Lisboa Josiléia Acordi Zanatta Elias Frank Araújo Cimélio Bayer Department of Agricultural Research and Diagnosis Agriculture SecretariatLivestock and Rural Development of Rio Grande do Sul.570Goncalves Dias St.Porto AlegreRio Grande do SulBrazil Department of Soil Science “Luiz de Queiroz”College of Agriculture/University of Sao PauloPadua Dias Ave 11PiracicabaSao PauloBrazil Embrapa Floretas Estrada da Ribeirakm 111ColomboParanáBrazil CMPC Celulose RiograndenseSao Geraldo St.GuaíbaRio Grande do Sul 1680Brazil Department of Soil Science Federal University of Rio Grande do SulPorto AlegreBrazil

Eucalyptus harvest residues are attractive energy production resources for the forestry ***,their removal can have adverse impacts on soil quality and forest productivity,especially in sandy *** this study,we assessed the effects of Eucalyptus harvest residue managements with variable intensity on forest productivity and on physical,chemical,and biological indicators of the soil *** experiment was conducted in a Quartzipsamment(33 g kg-1clay)planted with Eucalyptus saligna in Barra do Ribeiro in southern *** the Eucalyptus was planted,residues from the previous rotation were subjected to five different management treatments:(1)FRM,in which all forest residues(bark,branches,leaves,and litter)were allowed to remain on the soil and only trunk wood was removed;(2)FRMB,in which was identical to FRM except that bark was also removed;(3)FRMBr,in which only trunk wood and branches were removed;(4)FRR,which involved removing all types of residues(bark,branches,leaves,and litter);and,(5)FRRs,in which all forest residues from the previous rotation were removed,and leaves and branches from the new plantation were prevented from falling onto the soil surface using a shade *** years after planting,soil samples were collected at four different depths(0-2.5,2.5-5,5-10,and 10-20 cm)to determine 17 soil chemical,physical,and biological *** results were combined into a soil quality index(SQI)using the principal component analysis *** SQI reduced by 30%,in the 0-20 cm layer,due to removal of harvest residues from the previous rotation,and collection of litter before it falls on the *** main drivers of SQI reduction were the principal components associated with soil organic matter and biological ***,the SQI was positively linearly related to tree height at P<0.01 and to tree diameter at breast height at P=*** adverse impact on soil quality and forest productivity in our study indicates that removal

关键词： Forest residues Soil health Soil organic carbon Microbial biomass Soil conservation

Endophytic fungi harbored in Cannabis sativa L.:diversity and potential as biocontrol agents against host plant-specific phytopathogens

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Fungal Diversity 2013年第3期60卷 137-151页

作者： Parijat Kusari Souvik Kusari Michael Spiteller Oliver kayser Department of Biochemical and Chemical Engineering Chair of Technical BiochemistryTU DortmundEmil-Figge-Str.6644227 DortmundGermany Institute of Environmental Research(INFU)of the Faculty of Chemistry Chair of Environmental Chemistry and Analytical ChemistryTU DortmundOtto-Hahn-Str.644221 DortmundGermany

The objective of the present work was isolation,phylogenetic characterization,and assessment of biocontrol potential of endophytic fungi harbored in various tissues(leaves,twigs,and apical and lateral buds)of the medicinal plant,Cannabis sativa L.A total of 30 different fungal endophytes were isolated from all the plant tissues which were authenticated by molecular identification based on rDNA ITS sequence analysis(ITS1,5.8S and ITS2 regions).The Menhinick’s index revealed that the buds were immensely rich in fungal species,and Camargo’s index showed the highest tissue-specific fungal dominance for the *** most dominant species was Penicillium copticola that could be isolated from the twigs,leaves,and apical and lateral buds.A detailed calculation of Fisher’s log series index,Shannon diversity index,Simpson’s index,Simpson’s diversity index,and Margalef’s richness revealed moderate overall biodiversity of *** endophytes distributed among its *** fungal endophytes were challenged by two host phytopathogens,Botrytis cinerea and Trichothecium roseum,devising a dual culture antagonistic assay on five different *** observed 11 distinct types of pathogen inhibition encompassing a variable degree of antagonism(%)on changing the *** revealed the potential chemodiversity of the isolated fungal endophytes not only as promising resources of biocontrol agents against the known and emerging phytopathogens of Cannabis plants,but also as sustainable resources of biologically active and defensive secondary metabolites.

关键词： Cannabis sativa Endophytic fungi Fungal diversity Antagonism Botrytis cinerea Trichothecium roseum

Cannabinoids Production by Hairy Root Cultures of <i>Cannabis sativa</i>L.

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American Journal of Plant Sciences 2015年第11期6卷 1874-1884页

作者： Sayed Farag Oliver kayser Technische Biochemie Fachbereich Bio- und Chemieingenieurwesen Technische Universit&aumlt Dortmund Dortmund Germany

Tetrahydrocannabinol (THC) derivatives are used clinically as analgesic, anti-inflammatory, appetite stimulant, anti-emetic and anti-tumor cannabinoids. THC and its related compounds are at present obtained by extraction from intact Cannabis plants or chemical synthesis, but plant cell cultures may be an alternative source of production. In the present study, hairy root cultures of C. sativa (Cannabaceae) were induced by incubation of aseptically grown callus culture with solid B5 medium supplemented with 4 mg/l naphthaleneacetic acid in darkness at 25°C. Hairy root growth profiles in shake flask, increased periodically during 35 days of growth cycle. The cannabinoid contents produced in minor levels and remained below 2.0 μg/g dry weight. The contents of can-nabinoid were analyzed by liquid chromatography and confirmed by mass spectrometry.

关键词： Tetrahydrocannabinol Cannabinoids Callus Hairy Root Cannabis sativa

“My Unborn Baby Saved My Life”

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语言教育 1999年第3期 24-29页

作者：青闰 Elisa kayser Klein

The winter’s first snow covered our rhododendron bush-ers like a pure,downy baby’s *** I gazed out my bed-room window,I wondered if the baby growing inside me wouldlove to make snow angels and watch crystallized fla... 详细信息

关键词： My Unborn Baby Saved My Life

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路表温度对沥青路面疲劳损伤的影响

公路交通科技 2013年第1期30卷 1-5,16页

作者：韦璐 Sascha kayser Frohmut WELLNER 安徽建筑工业学院土木工程学院安徽合肥230601 德累斯顿工业大学城市和路面工程研究所德国德累斯顿01069

为准确评价温度影响下沥青路面结构的抗疲劳性能,解决采用某单一固定温度预估疲劳损伤不够精确的问题,以德国德累斯顿工业大学提出的路面温度场预估模型为例,基于Miner疲劳累积损伤定理,分析路表不同温度及其组合对沥青路面疲劳损伤的... 详细信息

为准确评价温度影响下沥青路面结构的抗疲劳性能,解决采用某单一固定温度预估疲劳损伤不够精确的问题,以德国德累斯顿工业大学提出的路面温度场预估模型为例,基于Miner疲劳累积损伤定理,分析路表不同温度及其组合对沥青路面疲劳损伤的影响。通过大量实测的路表温度数据,确定不同的路表温度组合及其组合内温度区间的温度代表值,研究路面结构疲劳损伤变化的规律。分析结果表明:采用由多个温度区间组成的路表温度组合预估疲劳损伤比用某单一固定路表温度预估更精确;组成路表温度组合的温度区间划分越多,路面结构疲劳损伤预估的精度越高;温度区间划分越少,区间内选取不同的温度代表值预估路面结构疲劳损伤差异越大;温度区间内温度代表值取区间上限高温,对沥青路面结构疲劳损伤的影响远比区间下限低温影响大。

关键词：道路工程沥青路面计算机仿真路表温度组合疲劳损伤温度区间

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了解ASE中的外键验证技术

铁路计算机应用 2007年第11期16卷 57-59页

作者： Carl kayser

看来并非所有的用户都了解有关ASE中的外键技术的一些问题。本文将通过说明一些鲜为人知的外键限制问题以及用于验证外键的各种查询，尽力填补这一知识空缺。我们还将演示一种用来分析和综合临时表的技术。

关键词：验证技术 ASE 外键临时表查询

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太阳,创造沙子新生命

小哥白尼（趣味科学） 2013年第7期 33-35页

作者：小凝 Markus kayser

太阳又立功了!只需要晒晒太阳,沙子便能在一台机器中长成一件奇特的艺术品。怎么样,这个创意是不是超级"赞"?不过,这台"梦幻机器"看起来却有一种似曾相识,却又不敢相认的感觉……它和太阳能发电装置难道是亲兄弟?这是一台神奇的机器,名... 详细信息

太阳又立功了!只需要晒晒太阳,沙子便能在一台机器中长成一件奇特的艺术品。怎么样,这个创意是不是超级"赞"?不过,这台"梦幻机器"看起来却有一种似曾相识,却又不敢相认的感觉……它和太阳能发电装置难道是亲兄弟?这是一台神奇的机器,名叫"太阳能烧结机"。它能以全自动的方式将阳光和沙子转化成玻璃制品。它先是利用汇聚的光线,将一些沙子加热至熔点,然后再将熔化的沙子冷却并凝结成固体(即变成玻璃)。它还可以导入计算机的设计,直接形成你想要的造型。更奇妙的是。

关键词：新生命烧结机子瑞

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