Impact of Crop Diversity, Fertilization and Legumes on Soil Organic Carbon in Grasslands

Agricultural soil quality is decreasing as a result of the expansion and intensification of agriculture. A key indicator of soil quality is soil organic carbon (SOC) which is degraded when land is converted from natural to cultivated systems and subject to intensive agricultural land use, reflecting reduced soil fertility and productivity. The aim of this study was to examine the effect of crop diversity, fertilizing levels and legumes on SOC accumulation in 3-year-old perennial production grasslands in Alnarp, Sweden. Since the soil was assumed to have a negligible content of inorganic (pH < 7), total carbon was used as an estimate of SOC. No significant differences in SOC depending on crop diversity, nitrogen fertilization treatment or presence of legumes were identified. The absence of significant differences was potentially due to local soil heterogeneity, where SOC was significantly dependent on the positioning within the researched blocks in the field, rather than on treatments. By examining how agricultural land management affect SOC contents in arable lands, methods enhancing soil C accumulation can be developed and improved, leading to extended agricultural soil quality and food production.För 10 000 år uppfanns jordbruket – en av mänsklighetens absolut viktigaste uppfinningar som gett oss oanade möjligheter till utvecklig. Sedan årtusende har vi brukat jord för matproduktion, men bara under de senaste 50 åren har det skett stora förändringar i hur vi bearbetar och behandlar våra jordbruksmarker. Extensiva tillsatsmedel, såsom besprutningsmedel och kemisk gödsling, i kombination med en allt mer intensiv markanvändning, har lett till att produktiviteten slagit nya rekord. Samtidigt beskrivs just denna förändring som en av mänsklighetens största och mest kritiskt omfattande förändringar av vår miljö. Nu står vi inför den stora utmaningen att ytterligare öka jordbrukets produktivitet för att föda en växande världsbefolkning, men samtidigt värna om och behålla, eller till och med öka, kvaliteten hos den odlade jorden för att försäkra oss om att våra jordar inte utarmas. Det innebär att vi måste utveckla nya odlingstekniker och hitta sätt som minskar jordbrukets påverkan på miljön. När mark används för odling minskar jordens kolhalt med upp till 75%, vilket har en negativ påverkan på jordkvalitén och väcker stark oro gällande hållbarheten och produktiviteten av vårt framtida jordbruk. För att bestämma hur jordens kvalitet påverkas av odling och hur hållbara olika odlingssätt är används ofta organiskt markkol som en indikator. Med detta i åtanke valde jag att undersöka hur sättet gräsmarker bearbetas och brukas påverkar halter av organiskt markkol, som en indikator av jordkvalitén. Närmare bestämt undersökte jag om gröddiversitet, mängden tillsatt kvävegödsel och baljväxter har en påverkan på organiskt markkol. För att säkerställa en effektiv matproduktion och samtidigt begränsa jordbrukets miljöpåverkan krävs det att vi förändrar sättet på hur våra jordbruksmarker bearbetas. Att hitta nya sätt att odla och samtidigt öka halten av organiskt markkol kan vara ett viktigt steg på vägen mot ett mer hållbart jordbruk

Sex pheromones and plant volatiles for control of orchard insects

Pheromone-based methods for control of orchard insect

The Significance of the New Testament Concept In the Name

In the following pages I am presenting as clearly as possible the origin as well as the meaning of the New Testament formula in the name in the light of the most up-to-date research in the field of New Testament study. I am presenting what I believe to be the most plausible explanation. Further research by others may result in a more satisfactory solution

Tension-tension Fatigue Behavior of Nextel™ 720/Alumina-mullite Ceramic Composite at 1200°C in Air and in Steam

Uniaxial tension-tension fatigue performance of an oxide-oxide continuous fiber ceramic composite was studied at 1200°C in laboratory air and in steam. The composite is reinforced with laminated, 0/90 mullite/alumina (NEXTEL™720) fibers woven in an eight-harness satin weave and has a porous alumina/mullite matrix. There is no interphase between the fiber and matrix. The composite relies on the porous matrix for crack deflection and flaw tolerance. Tension-tension fatigue was examined for maximum stresses of 45 – 136 MPa in air and in steam. To assess the effects of the steam environment on fatigue performance, experimental results obtained in air are compared to those obtained in steam. The retained properties of all specimens that achieved fatigue run-out were characterized. Composite microstructure, as well as damage and failure mechanisms, were examined

Parametric sensitivity analysis of microscrews

The research and development of a popular, publicly available microscrew system required an analysis of fastener strength. This analysis was performed using a Finite Element Analysis (FEA) program. ANSYS was used to model and stress the fasteners through various loading schemes. A simplified model was constructed due to limitations in model size.;The analysis required key parameters to be changed slightly. These parameters were socket depth and socket diameter. Changing these parameters had a substantial affect on the strength of the fastener.;Torque and rotation to tension analyses were performed on the microscrew to determine the validity of the ANSYS computation results. This data also provided complimentary information on the mechanics of a threaded assembly

Combining mutualistic yeast and pathogenic virus - a novel method for codling moth control

The combination of a pathogenic virus and mutualistic yeasts isolated from larvae of codling moth Cydia pomonella is proposed as a novel insect control technique. Apples were treated with codling moth granulovirus (CpGV) and either one of three yeasts, Metschnikowia pulcherrima, Cryptococcus tephrensis, or Aureobasidium pullulans. The combination of yeasts with CpGV significantly increased mortality of neonate codling moth larvae, compared with CpGV alone. The three yeasts were equally efficient in enhancing the activity of CpGV. The addition of brown cane sugar to yeast further increased larval mortality and the protection of fruit against larvae. In comparison, without yeast, the addition of sugar to CpGV did not produce a significant effect. A field trial confirmed that fruit injury and larval survival were significantly reduced when apple trees were sprayed with CpGV, M. pulcherrima, and sugar. We have shown earlier that mutualistic yeasts are an essential part of codling moth larval diet. The finding that yeast also enhances larval ingestion of an insect-pathogenic virus is an opportunity for the development of a novel plant protection technique. We expect the combination of yeasts and insect pathogens to essentially contribute to future insect management

Attractive plant volatiles as a control method against apple fruit moth (Argyresthia conjugella Zell.)?

Apple fruit moth, Argyresthia conjugella Zell. (Lepidoptera: Argyresthiidae), is the most important pest of apples in Scandinavia. In years when its primary host, rowan (Sorbus aucuparia L.), has little or no berries for egglaying, female A. conjugella fly into apple orchards to lay their eggs. In some years the entire apple crop can be destroyed. Volatiles from apples and rowan have been collected and identified. In GC-EAD tests females have responded to several compounds found in both rowan and apple. Some of these compounds were used in field trapping tests during 2002, and a mixture of two compounds trapped significantly more females and males compared to control traps. However, field trapping results from 2003 indicate that the two-compound blend seem to trap insects too late in the season to prevent egglaying in apples. Several new compounds were also tested in 2003, and some of these gave promising results. The results will be discussed in relation to use attractive plant volatiles as a control method against A. conjugella females

New fabrication techniques for high quality photonic crystals

We have developed new methods for the fabrication of high quality two-dimensional (2D) and three-dimensional (3D) photonic crystals. These techniques involve anisotropic etching and steam oxidation of AlAs mask layers. We have made manufacturable 2D photonic crystals with high aspect ratios for use as micropolarizers and have measured extinction ratios larger than 800 to 1 between TE and TM modes transmitted through these structures. The new Al2O3 mask fabrication technique also allows us to fabricate 3D structures with up to six repeating layers in depth and over 90% attenuation in the band gap region. Here, we show the fabrication details and performance of 2D and 3D photonic crystals

ER localized bestrophin1 activates Ca2+ dependent ion channels TMEM16A and SK4

Bestrophins form Ca2+ activated Cl- channels and regulate intercellular Ca2+ signaling1. We demonstrate that bestrophin 1 is localized in the endoplasmic reticulum (ER), where it physically interacts with stromal interacting molecule 1 (Stim1), the ER-Ca2+ sensor2,3. Intracellular Ca2+ transients in HEK293 cells elicited by stimulation of purinergic P2Y2-receptors were augmented but more transient after expression of hBest1, in contrast to dominant negative hBest1-R218C, which attenuated Ca2+ increase. The p21-activated protein kinase Pak2 was found to phosphorylate hBest1, thereby enhancing Ca2+ signaling and activation of Ca2+ dependent Cl- (TMEM16A)4 and K+ (SK4)5 channels. Lack of bestrophin 1 expression in respiratory epithelial cells of mBest1 knockout mice caused expansion of ER cisterns and induced Ca2+ deposits. We propose that hBest1 is important for Ca2+ handling of the ER store, probably by controlling the function of Stim1 and by acting as a counter-ion channel to balance transient membrane potentials occurring through inositol trisphosphate (IP3) induced Ca2+ release and refill of the ER-Ca2+ store. Thus bestrophin 1 controls activation of Ca2+ dependent ion channels by regulation of compartmentalized Ca2+ signaling