Die Beeinflussung des Zucker- und Säuregehaltes von Traubenbeeren durch künstliche Veränderung der Umweltbedingungen

Mit Hilfe künstlichen Windschutzes und künstlicher Schattierung in der Zeit zwischen Rebblüte und Traubenernte wurden in einem 2jährigen Freilandversuch veränderte meteorologische Bedingungen im Rebbestand erzeugt. Während die erste Maßnahme ohne meßbare Wirkung blieb, hemmte die zweite Beerenwachstum und -reife erheblich. Durch die Schattierung war die Einstrahlung auf 40-50% der natürlichen Werte reduziert, und demzufolge lagen hier Luft-, Boden- und vor allem Pflanzentemperatur tagsüber relativ niedrig.Unter den strahlungsarmen Bedingungen erreicht der Zuckergehalt der Beeren erwartungsgemäß weniger hohe Werte: Das Mostgewicht liegt zur Erntezeit 8-14 °Öchsle unter der Kontrolle. Es kann gezeigt werden, daß dies die Folge eines späten Reifebeginns (Beginn Phase IV des Beerenwachsturns), nicht aber die einer geringeren Zuckereinlagerungsgeschwindigkeit ist. Die eigentliche Reifephase wird durch ungünstige Umweltbedingungen verkürzt, andererseits scheint die Intensität der Zuckerakkumulation durch ökologische Faktoren in weiten Grenzen nicht beeinflußbar zu sein. Da sich die Schattierungsmaßnahme in einer starken Ertragsdepression im Folgejahr auswirkt, kommt die schwache Leistung dieser Reben im Beerenzuckergehalt am Ende der 2. Versuchsperiode besonders deutlich zum Ausdruck: Nur 59 g pro Stock gegenüber 209 g der Kontrolle.Im schattierten Bestand erfolgt der Säureaufbau in den Beeren verlangsamt; das sog. Säuremaximum tritt - in Übereinstimmung mit dem verzögerten Beginn der Zuckereinlagerung - verspätet ein und liegt weniger hoch. Der anschließende Abbau der Beerensäure verläuft bei den vergleichsweise niedrigen Temperaturen langsamer und wird hauptsächlich durch das Verhalten der Apfelsäure bestimmt, während sich die Weinsäure indifferent verhält. Zur Zeit der Lese enthalten daher die unter der Schattierung gewachsenen Trauben noch relativ viel Säure.The concentration of sugars and organic acids in grape berries as affected by artificial modifications of the environmentIn a 2-year field experiment, meteorological conditions in the vineyard were changed by artificial windbreak and shading during the period of berry set to fruit maturity. While the first treatment caused no measurable effect, berry growth and ripening were considerably inhibited by the second one. In consequence of shading, the solar radiation was reduced to 40-50°/o of the original values and, thus, air, soil, and especially plant temperature were comparatively low in the daytime.As expected, the amount of sugars in the berries grown under low radiation conditions is decreased. Total soluble solids range 8-14 °Öchsle below the control at vintage. lt can be shown that this is the result of a late beginning of phase IV of the berry growth and not the consequence of a lower increase of sugar accumulation. This phase is shortened by unfavourable environmental conditions. The intensity of sugar accumulation, on the other hand, seems not to be susceptible on a large scale to ecological factors. Shading causes a !arge depression of yield in the following year, therefore the low sugar content of the berries in these grape-vines is especially evident at the end of the second experimental period: Only 59 g per vine, compared with 209 g of the control.The synthesis of organic acids is retarded in the berries of the shaded canopy; in accordance with the delayed start of sugar accumulation, the so-called acid maximum is late and lowered. The subsequent decrease of organic acids in the berry proceeds slower at comparatively low temperatures and is mainly due to malic acid, whereas tartaric acid is indifferent. At harvest-time, grape-berries grown under shading still contain a high acid concentration

Künstliche Veränderung der meteorologischen Verhältnisse im Rebbestand und ihre Auswirkungen auf das Größenwachstum der Traubenbeeren

 Mit Hilfe künstlicher Schattierung und künstlichen Windschutzes während der Zeit zwischen Rebblüte und Traubenernte wurden in einem 2jährigen Freilandversuch veränderte Bestandsklimate erzeugt. Der Einfluß dieser Maßnahmen auf die meteorologischen Verhältnisse irri Rebbestand wurde gemessen und die Auswirkung auf das Wachstum der Traubenbeeren untersucht.Der Windschutz erwies sich trotz erheblicher Verringerung der Windgeschwindigkeit als wenig wirkungsvoll: Die Temperaturverhältnisse im Bestand wurden nicht meßbar verändert und Auswirkungen auf das Beerenwachstum konnten nicht nachgewiesen werden.Dagegen waren Globalstrahlung und Helligkeit unter der Schattierung so stark reduziert, daß das Wachstum der Beeren in erheblichem Maße beeinträchtigt wurde. Die an einem sommerlichen Strahlungstag gemessene Globalstrahlung von 410 ca!· cm-2 war auf 160 cal · cm-2 abgesenkt, und während der etwa 100tägigen Versuchsdauer empfing der schattierte Bestand nur etwa 13 kc al · cm-2 gegenüber 29 kcal · cm-2 der Kontrolle. Infolge der abgeschirmten Sonnenstrahlung war insbesondere die Pflanzentemperatur, weniger dagegen die Lufttemperatur im Bestand erniedrigt. Das Einzelbeerengewicht blieb in beiden Versuchsjahren weit hinter den „normalen" Werten zurück, so daß eine Ertragseinbuße infolge Kleinbeerigkeit von rund 1 Drittel entstand.Experimental modification of the meteorological conditions within a grape canopy and their effects on berry growthIn a 2-year field experiment microclimatic changes were induced by artificial shading and windbreak during the period between bloom and vintage. The effects of these treatments on the meteorological conditions in the vineyard and on the growth of the berries were investigated.In spite of considerable diminution in the wind speed, the windbreak proved little effective: the temperature regime within the canopy was not measurably changed and effects on the berry growth could not be ascertainecl.On the contrary, solar radiation (0.3-2.5 µm) and light intensity were reduced by shacling to such an extent that the growth of the berries was considerably impaired. The solar radiation, measured on a clear summer day, was decreased from 410 cal · cm-2 to 160 cal · cm-2, and for the 100-clay period the shadecl vines received just approximately 13 kcal · cm-2 against 29 kcal · cm-2 of the control. In consequence of the reduced insolation, the plant temperature, in particular, climinished, whereas the air-temperature within the canopy was just slightly lowered. The berry weight dropped off from the "normal" values so that a loss of yield, amounting to about 11a, was caused by small berries

Einfluß der Samen auf die Beerenreife bei Vitis vinifera L.

An drei verschiedenen Rebsorten wurde jeweils der Einfluß des Samengehaltes auf den Reifeverlauf der Beeren untersucht. Es stellte sich heraus, daß die bekannte Erscheinung einer früheren Reife der Beeren mit relativ geringem Samengehalt auf eine früher beginnende und dadurch länger andauernde Wachstumsphase IV (Phase der Zuckereinlagerung) zurückzuführen ist. Die Intensität der Zuckereinlagerung scheint indes sortenspezifisch und vom Samengehalt unabhängig zu sein.Influence of the seeds on the maturation of Vitis vinifera L. berriesThe influence of the seed number on berry ripening was investigated in three different varieties. The well-known symptom of an earlier ripeness of the berries with a relative small seed number proved to be a result of an earlier beginning and, thus, a longer duration of phase IV of the berry development (phase of sugar accumulation). The intensity of the sugar accumulation, however, seems to be specific to variety and independent of the seed number

Einfluß der Traubentemperatur auf Beerenwachstum und Beerenreife der Rebsorte Silvaner

In den Versuchsjahren 1970-1973 wurden einzelne Trauben der Rebsorte Silvaner in den Wachstumsphasen 1-111 (Blühende bis Beginn der Zuckereinlagerung) und IV (Phase der Zuckereinlagerung) beheizt. Die Beheizung bewirkte eine mittlere Temperaturerhöhung der Trauben um 2-5 °c (Phasen 1-111) bzw. um 3-6 °C (Phase IV).Ein Temperaturanstieg in den Phasen 1-111 erhöhte das Einzelbeerengewicht um durchschnittlich 0,18 g und den Gehalt an freier titrierbarer Säure um 2,3 g/l. Die Erhöhung des Säuregehaltes ist durch einen intensiveren Anstieg der Apfelsäure bedingt. Ein Temperaturanstieg in der Reifephase IV erhöhte nur im kühlen Versuchsjahr 1972 das Einzelbeerengewticht, während der Gehalt der Beeren an Zucker um 7 °Oe erhöht und der an freier titrierbarer Säure um durchschnittlich 2,1 g/l vermindert war. Die Säureverminderung ist hauptsächlich auf einen verstärkten Abbau an Apfelsäure zurückzuführen. Eine Nachwirkung höherer Temperaturen während der Phasen 1-111 auf die Stoffwechselvorgänge in Phase IV ist erkennbar. Sie äußert sich in der Erhöhung des Säuremaximums und in einer Vorverlegung der Reifephase IV.Influence of grape temperature on growth and maturity of Sylvaner berriesIn the years from 1970 to 1973 investigations were carried out on the effects of moderately heating individual grapes of Sylvaner during development stages 1-111 (end of flowering until the beginning of sugar accumulation) and IV (phase of sugar accumulation). The heating effected a medium rise in temperature of the grapes by 2-5 °C (stages 1-111) and by 3-6 °C (stage IV), respectively. A rise in temperature during stages I-111 increased the per-berry weight by 0.18 g on an average and the content of free titratable acid by 2.3 g/l. The increase in the acid content is due to an enhanced production of malic acid. A rise in temperature during stage IV of berry development increased the perberry weight only in the cool year 1972, whereas the content of sugar in the berries was increased by 7 °Oe and the content of free titratable acid was diminished by 2.1 g/l on an average. The decrease in acid is mainly due to a forced decomposition of malic acid. An after-effect of higher- temperatures during stages I-111 on the metabolism during stage IV is recognizable. lt is manifested in the increase of the acid maximum and in an advanced stage IV of berry development

Overcoming Public Resistance to Carbon Taxes

Carbon taxes represent a cost-effective way to steer the economy toward a greener future. In the real world, their application has however been limited. In this paper, we address one of the main obstacles to carbon taxes: public opposition. We identify drivers of and barriers to public support, and, under the form of stylized facts, provide general lessons on the acceptability of carbon taxes. We derive our lessons from a growing literature, as well as from a combination of policy “failures” and “successes.” Based on our stylized facts, we formulate a set of suggestions concerning the design of carbon taxes. We consider the use of trial periods, tax escalators, environmental earmarking, lump-sum transfers, tax rebates, and advanced communication strategies, among others. This paper contributes to the policy debate about carbon taxes, hopefully leading to more success stories and fewer policy failures

Mentoring initiatives as talent management innovations

Originality/value of paper: The exploration of contemporary mentoring initiatives in the international hospitality industry identifies the value of cross-industry TM innovations stretching beyond stakeholders, such as educators, employers and policy-makers. It identifies mentoring initiatives as mechanisms for creating bonds and bridges between those industry aspirants at various career stages where diversity and inclusion may be a challenge in a fragmented and dispersed sector

The fiscal benefits of stringent climate change mitigation: an overview

The Paris Agreement’s very ambitious mitigation goals, notably to ‘pursue efforts’ to limit warming to 1.5°C, imply that climate policy will remain a national affair for some time. One key obstacle to very ambitious national mitigation is that some policy makers perceive this to be in competition with major goals of fiscal policy, such as public investment or debt reduction. However, climate policy may actually contribute to these other objectives. Importantly, many fiscal implications of substantial carbon prices, which are essential for stringent mitigation targets such as the 1.5°C goal, have long been neglected by economic analyses of climate change mitigation. We systematically review recent contributions on interactions between climate policy and public finance, which include many topics beyond the classic `double dividend’ of environmental tax swaps. We can thus identify new conclusions about climate policy designs that may overcome fiscal objections and research gaps. We find that national climate policy often aligns with other objectives, provided that climate policies and fiscal policies are integrated well. A first class of interactions concerns public revenue-raising: carbon pricing can replace distortionary taxes and alleviate international tax competition; climate policy also changes asset values, which impacts the base of non-climate taxes and boosts productive investment. Second, they concern public spending, which needs to be restructured as a part of climate policy, while carbon pricing revenues may be recycled for public investment. Third, distributional impacts of climate policies include changes to household expenditures, to asset values and to employment; balancing them often requires fiscal policies. Our findings underline that jointly considering climate policy and fiscal policy can help to make substantial mitigation politically feasible.</p

The fiscal benefits of stringent climate change mitigation: an overview

The Paris Agreement’s very ambitious mitigation goals, notably to ‘pursue efforts’ to limit warming to 1.5°C, imply that climate policy will remain a national affair for some time. One key obstacle to very ambitious national mitigation is that some policy makers perceive this to be in competition with major goals of fiscal policy, such as public investment or debt reduction. However, climate policy may actually contribute to these other objectives. Importantly, many fiscal implications of substantial carbon prices, which are essential for stringent mitigation targets such as the 1.5°C goal, have long been neglected by economic analyses of climate change mitigation. We systematically review recent contributions on interactions between climate policy and public finance, which include many topics beyond the classic `double dividend’ of environmental tax swaps. We can thus identify new conclusions about climate policy designs that may overcome fiscal objections and research gaps. We find that national climate policy often aligns with other objectives, provided that climate policies and fiscal policies are integrated well. A first class of interactions concerns public revenue-raising: carbon pricing can replace distortionary taxes and alleviate international tax competition; climate policy also changes asset values, which impacts the base of non-climate taxes and boosts productive investment. Second, they concern public spending, which needs to be restructured as a part of climate policy, while carbon pricing revenues may be recycled for public investment. Third, distributional impacts of climate policies include changes to household expenditures, to asset values and to employment; balancing them often requires fiscal policies. Our findings underline that jointly considering climate policy and fiscal policy can help to make substantial mitigation politically feasible.</p

Climate action with revenue recycling has benefits for poverty, inequality and well-being

Existing estimates of optimal climate policy ignore the possibility that carbon tax revenues could be used in a progressive way; model results therefore typically imply that near-term climate action comes at some cost to the poor. Using the Nested Inequalities Climate Economy (NICE) model, we show that an equal per capita refund of carbon tax revenues implies that achieving a 2 °C target can pay large and immediate dividends for improving well-being, reducing inequality and alleviating poverty. In an optimal policy calculation that weighs the benefits against the costs of mitigation, the recommended policy is characterized by aggressive near-term climate action followed by a slower climb towards full decarbonization; this pattern—which is driven by a carbon revenue Laffer curve—prevents runaway warming while also preserving tax revenues for redistribution. Accounting for these dynamics corrects a long-standing bias against strong immediate climate action in the optimal policy literature

Protecting the poor with a carbon tax and equal per capita dividend

We find that if all countries adopt the necessary uniform global carbon tax and then return the revenues to their citizens on an equal per capita basis, it will be possible to meet a 2 °C target while also increasing wellbeing, reducing inequality and alleviating poverty. These results indicate that it is possible for a society to implement strong climate action without compromising goals for equity and development