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11	N-Nachlieferungspotenzial an zwei Pfirsichstandorten Birth, Volker 27 February 2018 (has links) (PDF) Ein wichtiger Aspekt bei der Kultur von Pfirsichen (Prunus persica) ist die optimale, bedarfsgerechte N-Versorgung. Durch diese werden Höhe und Qualität der Erträge sowie die Gesundheit der Pflanzen beeinflusst, aber auch unerwünschte Effekte auf die Umwelt vermieden. Ziel der Arbeit waren daher Empfehlungen zur zukünftigen Handhabung der N-Versorgung an zwei Beispielstandorten und zur praktikabelsten Kulturweise. Es wurden Nmin-Bestimmungen, Inkubationsversuche und Thermogravimetrische Bodenanalysen durchgeführt, um die N-Nachlieferung aus der organischen Bodensubstanz an den Standorten zu beschreiben. Die Ergebnisse zeigen eine deutliche Überversorgung der Kultur im Hausgarten auf - die Pfirsiche auf der untersuchten Obstwiese sind hingegen optimal mit N versorgt. Empfohlen wird deshalb eine Reduzierung der organischen Düngung im Hausgarten, verbunden mit einem Verzicht auf frisches organisches Schnittmaterial als Dünger. Bei der Pfirsichkultur auf der Obstwiese ist die Einführung von Mulchmaßnahmen überlegenswert. Der Standort mit begrünter Bodenoberfläche ist gegenüber dem Hausgarten mit offener Bodenoberfläche vorzuziehen, da die N-Nachlieferung bei einer Begrünung einfacher handhabbar ist und weniger Risiken hinsichtlich einer N-Überversorgung vorhanden sind. / An important aspect in the cultivation of peaches (Prunus persica) is the optimal, demand-oriented N-supply. This influences the amount and quality of yields and the health of the plants, but also prevents undesirable effects on the environment. The aim of the work was therefore to make recommendations for future use of the N-supply at two sample locations and for the most practicable cultivation method. Nmin determinations, incubation experiments and thermogravimetric soil analyses were carried out to describe the N-supply from the organic soil substance at the sites. The results show a clear oversupply of the crop in the house garden - the peaches on the investigated fruit meadow, on the other hand, are optimally supplied with N. Therefore, it is recommended to reduce the amount of organic fertiliser in the garden, combined with the elimination of fresh organic cuttings as fertiliser. In peach cultivation on the fruit meadow, the introduction of mulching methods is worth considering. The location with a planted ground surface is preferable to the garden with an open ground surface, as the N-supply is easier to handle if greenery is present and there are fewer risks with regard to an N-oversupply. N-Nachlieferung N-Versorgung Pfirsich Düngung organische Bodensubstanz N-reproduction N-supply peach fertilization organic soil matter ddc:580 rvk:ZC 55240 rvk:ZC 17500
12	N-Nachlieferungspotenzial an zwei Pfirsichstandorten Birth, Volker 23 July 2015 (has links) Ein wichtiger Aspekt bei der Kultur von Pfirsichen (Prunus persica) ist die optimale, bedarfsgerechte N-Versorgung. Durch diese werden Höhe und Qualität der Erträge sowie die Gesundheit der Pflanzen beeinflusst, aber auch unerwünschte Effekte auf die Umwelt vermieden. Ziel der Arbeit waren daher Empfehlungen zur zukünftigen Handhabung der N-Versorgung an zwei Beispielstandorten und zur praktikabelsten Kulturweise. Es wurden Nmin-Bestimmungen, Inkubationsversuche und Thermogravimetrische Bodenanalysen durchgeführt, um die N-Nachlieferung aus der organischen Bodensubstanz an den Standorten zu beschreiben. Die Ergebnisse zeigen eine deutliche Überversorgung der Kultur im Hausgarten auf - die Pfirsiche auf der untersuchten Obstwiese sind hingegen optimal mit N versorgt. Empfohlen wird deshalb eine Reduzierung der organischen Düngung im Hausgarten, verbunden mit einem Verzicht auf frisches organisches Schnittmaterial als Dünger. Bei der Pfirsichkultur auf der Obstwiese ist die Einführung von Mulchmaßnahmen überlegenswert. Der Standort mit begrünter Bodenoberfläche ist gegenüber dem Hausgarten mit offener Bodenoberfläche vorzuziehen, da die N-Nachlieferung bei einer Begrünung einfacher handhabbar ist und weniger Risiken hinsichtlich einer N-Überversorgung vorhanden sind. / An important aspect in the cultivation of peaches (Prunus persica) is the optimal, demand-oriented N-supply. This influences the amount and quality of yields and the health of the plants, but also prevents undesirable effects on the environment. The aim of the work was therefore to make recommendations for future use of the N-supply at two sample locations and for the most practicable cultivation method. Nmin determinations, incubation experiments and thermogravimetric soil analyses were carried out to describe the N-supply from the organic soil substance at the sites. The results show a clear oversupply of the crop in the house garden - the peaches on the investigated fruit meadow, on the other hand, are optimally supplied with N. Therefore, it is recommended to reduce the amount of organic fertiliser in the garden, combined with the elimination of fresh organic cuttings as fertiliser. In peach cultivation on the fruit meadow, the introduction of mulching methods is worth considering. The location with a planted ground surface is preferable to the garden with an open ground surface, as the N-supply is easier to handle if greenery is present and there are fewer risks with regard to an N-oversupply. info:eu-repo/classification/ddc/580 ddc:580
13	Bewirtschaftung von Niedermooren in der gemäßigten Klimazone: Treibhausgasemissionen und Rentabilität Rebhann, Marco Frank 17 August 2018 (has links) Niedermoore sind durch Grundwasser beeinflusste Standorte, in denen Torf gebildet wird oder oberflächig ansteht. Sie emittieren durch mikrobiologische Prozesse Treibhausgase (THG). Wird der Grundwasserstand gesenkt, steigen Kohlendioxid und Lachgas Emissionen, während bei einer Anhebung vermehrt Methan emittiert wird. Weltweit wird davon ausgegangen, dass Moore 5 % der anthropogen verursachten Emissionen verursachen. Um THG-Emissionen entgegenzuwirken, wird die Anhebung des Grundwasserstandes diskutiert. Dies führt durch eingeschränkte Befahrbarkeit und geringeres Kulturartenspektrum zu einer kaum gegebenen Wirtschaftlichkeit. Es fehlt ein Vergleich der THG-Emissionen und der Rentabilität der Bewirtschaftungssysteme verschiedener Landnutzungssysteme für Niedermoorstandorte der gemäßigten Klimazone. Die bodenbürtigen THG-Emissionen wurden mit einer Metaanalyse zu Veröffentlichungen von THG-Messungen in Niedermooren der gemäßigten Klimazone ermittelt. Ebenfalls wurden die bewirtschaftungsabhängigen Emissionen ermittelt und zu Gesamtemissionen zusammengefasst. Für den Vergleich der Rentabilität der Bewirtschaftungssysteme wurden Kosten und Erlöse berechnet. Abschließend wurden Treibhausgasvermeidungskosten abgeschätzt Bei zunehmender Landnutzungsintensität und größeren Grundwasserflurabstand nahmen die Gesamt-THG-Emissionen zu. Durch die Bewirtschaftung verursachte Emissionen spielten im Vergleich zu den bodenbürtigen Emissionen kaum eine Rolle. Zur THG-Einsparung und der Torferhaltung sollte die Bewirtschaftung extensiviert werden. Im Rentabilitätsvergleich erwiesen sich intensive, im Vergleich zu extensive Bewirtschaftungssysteme ohne Förderung als wirtschaftlich. Subventionen und Förderungen um torf- und klimaschonende Praktiken zu unterstützen, sind unverzichtbar. Mit dieser Arbeit wurde erstmalig für Niedermoore ein systematischer Überblick über die Gesamt-THG-Emissionen und die Rentabilität gängiger Bewirtschaftungssysteme verschiedener Landnutzungssysteme gegeben. / Fens are sites influenced by the groundwater where peat is formed in or located in the upper soil layer. They emit greenhouse gases (GHG) through microbiological processes in which the main influencing factor is the groundwater level. The lowering of the groundwater level increases carbon dioxide and dinitrogen monoxide emissions, while higher groundwater levels lead to methane emissions. It is assumed that fens cause 5% of global anthropogenic GHG emissions. In order to save peat and reduce GHG emissions, rewetting fens has been discussed and applied. This leads to low profitable land use due to limited trafficability and cultivation options. There is a lack of comparison of management systems in different land use systems regarding GHG emissions and profitability on fenlands in the temperate climate zone. The soil-borne GHG emissions for the land use systems were identified with a meta-analysis of published measurements of GHG emissions on fenlands in the temperate climate zone. The GHG emissions due to cultivation and possible land use changes were identified and summarized as the overall emissions. Costs and revenues were calculated for comparability purposes of profitability of management systems. GHG abatement costs were estimated too. Results indicated that overall GHG emissions increase with higher land use intensity and deeper groundwater level. Management induced GHG emissions are negligible compared to the soil-borne emissions. Fenlands should be extensified to save peats and reduce GHG emissions. The comparison of profitability showed that management systems of intensive land use systems, in contrast to extensive land use systems, with the low groundwater level are broadly profitable without subsidies. Subsidies and grants are indispensable to promote peat-saving and climate-friendly practices. This thesis provides a systematic overview of overall GHG emissions and profitability of common management systems of fenlands. Emissionen Treibhausgase CO2 CH4 N2O Niedermoor Torf organischer Boden Wiedervernässung Emissions Greenhouse Gases CO2 CH4 N2O Fen Peat Organic Soil Rewetting ZC 13174 ZD 63100 ddc:630
14	Indicadores microbiológicos e bioquímicos da qualidade do solo em transição para cultivo orgânico de feijoeiro comum (Phaseolus vulgaris L.) / Microbiological and biochemical indicators of the quality of ground transitioning to organic cultivation of common bean (Phaseolus vulgaris L.) ROSA, Joyce Rover 30 May 2009 (has links) Made available in DSpace on 2014-07-29T15:16:36Z (GMT). No. of bitstreams: 1 Joyce Rover.pdf: 514538 bytes, checksum: aaa943196dccf7fe52627b0d975e29e2 (MD5) Previous issue date: 2009-05-30 / The soil quality indicators analyses during and after the transition period of conventional to organic production system are very important to evaluated the sustainability of agricultural systems. Soil microbiological and biochemical indicators shall quickly indicate changes occurred on both, soil management and production systems. The objective of this work was to evaluated shifts on microbiological and biochemical soil indicators of a conventional common bean production system in transition to an organic system, under conventional and non-tillage soil management systems after cover crops. Total enzymatic activity (AET), betaglucosidase activity (betaglucosidase), acid fosfatase activity (fosfatase), carbon (CBM) and nitrogen (NBM) of the microbial biomass, the basal soil respiration (RBS) and the metabolic quotient (qCO2) were evaluated on soil samples collected at tillage common bean cycle. The experiment was carried out at Embrapa Rice and Beans, in Santo Antônio de Goiás GO, and it was also collected soil samples in a secondary forest area close to the experiment to be used as a reference. The content of carbon and nitrogen of the soil microbial biomass, as well as, microbial and enzymatic activities in conventional and non-tillage systems were independent of the cover crop specie used. Under the experimental conditions, the soil management systems did not show effect in the enzymatic and microbial soil activities. The total and acid fosfatase enzymatic activities of the cropped soils were lower than in the forest soil. The betaglucosidase enzymatic activity was higher in cropped soil than under forest soil in the raining season and lower in the dry season. The soil tillage performed before common bean sowing promoted shifts on the CO2 efflux from soil to the atmosphere, which was verified by an increase on both, basal soil respiration and metabolic quotient. / A análise da qualidade do solo durante e após o período de transição de um sistema produtivo convencional para um sistema orgânico é importante como indicador de sustentabilidade. Indicadores microbiológicos e bioquímicos da qualidade do solo devem responder rapidamente a mudanças no manejo e alterações nos sistemas de produção. Assim, este experimento teve como objetivo avaliar as alterações nos indicadores microbiológicos e bioquímicos do solo em um sistema de produção em transição para cultivo orgânico do feijoeiro comum (Phaseolus vulgaris L.), sob sistema de preparo convencional (SPC) e direto (SPD) do solo, após o manejo de diferentes plantas de cobertura de solo. Avaliaram-se a atividade enzimática total (AET), a atividade de betaglicosidase (β-glicosidase) e de fosfatase ácida (Fosfatase), o carbono (CBM) e o nitrogênio (NBM) da biomassa microbiana, a respiração basal do solo (RBS) e o quociente metabólico (qCO2) em amostras de solo coletadas durante o ciclo de cultivo do feijoeiro comum. O experimento foi conduzido na Embrapa Arroz e Feijão, em Santo Antônio de Goiás GO e área de mata nativa próxima ao ensaio foi utilizada como referência. O teor de carbono e nitrogênio da biomassa microbiana no solo, assim como de atividades microbianas e enzimáticas avaliadas, tanto sob SPD quanto sob SPC, foi independente da espécie de planta de cobertura de solo utilizada. Nas condições testadas, o sistema de preparo de solo não teve influência na atividade das enzimas do solo e nem na atividade microbiana do solo. No solo agricultável testado, a atividade enzimática total e de fosfatase ácida foi menor do que em solo não agricultável. No período chuvoso, a atividade de betaglicosidase foi maior em solo agricultável do que em solo não agricultável e menor no período seco. O preparo do solo para a semeadura do feijoeiro comum provocou aumento da perda de gás carbônico, verificado em decorrência de aumento na respiração basal do solo e no quociente metabólico. Adubo verde manejo do solo matéria orgânica do solo qualidade do solo sustentabilidade Green manure soil management organic soil matter soil quality sustainability
15	Multispectral imaging of Sphagnum canopies: measuring the spectral response of three indicator species to a fluctuating water table at Burns Bog Elves, Andrew 02 May 2022 (has links) Northern Canadian peatlands contain vast deposits of carbon. It is with growing urgency that we seek a better understanding of their assimilative capacity. Assimilative capacity and peat accumulation in raised bogs are linked to primary productivity of resident Sphagnum species. Understanding moisture-mediated photosynthesis of Sphagnum spp. is central to understanding peat production rates. The relationship between depth to water table fluctuation and spectral reflectance of Sphagnum moss was investigated using multispectral imaging at a recovering raised bog on the southwest coast of British Columbia, Canada. Burns Bog is a temperate oceanic ombrotrophic bog. Three ecohydrological indicator species of moss were chosen for monitoring: S. capillifolium, S. papillosum, and S. cuspidatum. Three spectral vegetation indices (SVIs) were used to characterize Sphagnum productivity: the normalized difference vegetation index 660, the chlorophyll index, and the photochemical reflectance index. In terms of spectral sensitivity and the appropriateness of SVIs to species and field setting, we found better performance for the normalized difference vegetation index 660 in the discrimination of moisture mediated species-specific reflectance signals. The role that spatiotemporal scale and spectral mixing can have on reflectance signal fidelity was tested. We were specifically interested in the relationship between changes in the local water table and Sphagnum reflectance response, and whether shifting between close spatial scales can affect the statistical strength of this relationship. We found a loss of statistical significance when shifting from the species-specific cm2 scale to the spectrally mixed dm2 scale. This spatiospectral uncoupling of the moisture mediated reflectance signal has implications for the accuracy and reliability of upscaling from plot based measurements. In terms of species-specific moisture mediated reflectance signals, we were able to effectively discriminate between the three indicator species of Sphagnum along the hummock-to-hollow gradient. We were also able to confirm Sphagnum productivity and growth outside of the vascular growing season, establishing clear patterns of reflectance correlated with changes in the local moisture regime. The strongest relationships for moisture mediated Sphagnum productivity were found in the hummock forming species S. capillifolium. Each indicator Sphagnum spp. of peat has distinct functional traits adapted to its preferred position along the ecohydrological gradient. We also discovered moisture mediated and species-specific reflectance phenologies. These phenospectral characteristics of Sphagnum can inform future monitoring work, including the creation of a regionally specific phenospectral library. It’s recommended that further close scale multispectral monitoring be carried out incorporating more species of moss, as well as invasive and upland species of concern. Pervasive vascular reflectance bias in remote sensing products has implications for the reliability of peatland modelling. Avoiding vascular bias, targeted spectral monitoring of Sphagnum indicator species provides a more reliable measure for the modelling of peatland productivity and carbon assimilation estimates. / Graduate peatland peatland restoration peatland monitoring peatland modelling peat peat moss multispectral multispectral imaging multicamera array multitemporal multiple linear regression linear mixed effects Sphagnum sphagna Sphagnum capillifolium Sphagnum papillosum Sphagnum cuspidatum spatiospectral uncoupling near-sensing remote sensing phenospectral phenology phenologies phenospectral bias phenospectral libraries carbon assimilation carbon dioxide carbon dynamics carbon emissions carbon geographies carbon mineralization carbon sequestration carbon source carbon sink carbon storage irrecoverable carbon climate forcing methane Ecological Restoration restoration ecology ecohydrology ecohydrological restoration hydrology ecohydrological gradients ecological integrity reflectance nature based solutions ombrotrophic moss raised peatland mires mires photochemical reflectance index normalized difference vegetation index chlorophyll index climate change climate forcing climate envelope climatope nonvascular vascular bias plant functional type plant functional types structure equation models spectral vegetation indices hummock hollow acrotelm catotelm diplotelmic biocrusts organic soil periodicity moisture deficit senescence rejuvenescence productivity photosynthesis light use efficiency photosynthetic function photosynthetically active radiation water table hydrology rewetting depth to water table landscape change landscape degradation peat subsidence Burns Bog

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