Versuche mit Herbiziden in Gemeiner Ringelblume (Calendula officinalis L.) in Sachsen-Anhalt und Thüringen

Between 2000 and 2005 12 experiments with 18 herbicides were carried out in marigold in experimental stations and on marigold fields of Thuringian farms. The main objective of the tests was to get the necessary data for the authorization procedure according to the regulations of §?18 a PflSchG. Marigold plants are very susceptible against some herbicides Betanal Progress, Goltix Compact + ?l, Kontakt 320 SC, Lentagran WP und Stefes IPU. These herbicides and cause severe damages on this culture. The use oft the herbicides Bandur, BASTA and further herbicides with the active ingredient Glufosinat was authorized for the application in marigold according the regulations of §?18 a PflSchG in the past. The herbicides Devrinol FL, Fusilade MAX, Goltix 700 SC, Roundup UltraMAX und Targa Super can be used in artichoke according the regulations of §?18 b PflSchG. These herbicides aren??t enough for the chemical control of weeds likeEchinochloa spec.,Galinsoga spec., Polygonum spec. in marigold. In addition to the application of the herbicides mechanical measures are necessary.     

Effects of Sewage on the Chemical Composition of Piracicaba River,Brazil

Water samples were collected from 7 locations along major rivers of Piracicaba River basin for 22 months. The 4 upstream points represent non-polluted sites and the 3 downriver points represent polluted sites. Due to sewage input, concentrations of dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), major conservative cations and anions increased significantly in the polluted sites. The major increases were observed for sodium, chloride and sulfate. Nitrate was an exception for this pattern, with similar concentrations between polluted and non-polluted sites. The probable cause was reduction of nitrate to ammonium in the polluted sites, where anoxic conditions prevail. Most of the variables had an inverse correlation with water discharge, especially in the polluted points. The sewage load was diluted by precipitation and surface waters.     

Woher kommen wir und wohin gehen wir? – Analyse des deutschen Erwerbsobstbaus anhand eines Branchenlebenszyklus-Modells

Cassia et al. (2006) claim that each industry develops along a specific industry life cycle with four stages: introduction, growth, maturity and decline. This essay tries to analyze the German fruit-growing industry by the means of the industry life cycle model. The main aspects of the analysis are “consumption and prices”, “competition”, “product innovation” and “process innovation”. In summary, the German professional fruit-growing industry might be classified as to be in the mature stage.     

Biogeochemical cycles of nutrients in tropical Eucalyptus plantations: Main features shown by intensive monitoring in Congo and Brazil

The sustainability of fast-growing tropical Eucalyptus plantations is of concern in a context of rising fertilizer costs, since large amounts of nutrients are removed with biomass every 6–7 years from highly weathered soils. A better understanding of the dynamics of tree requirements is required to match fertilization regimes to the availability of each nutrient in the soil. The nutrition of Eucalyptus plantations has been intensively investigated and many studies have focused on specific fluxes in the biogeochemical cycles of nutrients. However, studies dealing with complete cycles are scarce for the Tropics. The objective of this paper was to compare these cycles for Eucalyptus plantations in Congo and Brazil, with contrasting climates, soil properties, and management practices.The main features were similar in the two situations. Most nutrient fluxes were driven by crown establishment the two first years after planting and total biomass production thereafter. These forests were characterized by huge nutrient requirements: 155, 10, 52, 55 and 23 kg ha^?1 of N, P, K, Ca and Mg the first year after planting at the Brazilian study site, respectively. High growth rates the first months after planting were essential to take advantage of the large amounts of nutrients released into the soil solutions by organic matter mineralization after harvesting. This study highlighted the predominant role of biological and biochemical cycles over the geochemical cycle of nutrients in tropical Eucalyptus plantations and indicated the prime importance of carefully managing organic matter in these soils. Limited nutrient losses through deep drainage after clear-cutting in the sandy soils of the two study sites showed the remarkable efficiency of Eucalyptus trees in keeping limited nutrient pools within the ecosystem, even after major disturbances. Nutrient input–output budgets suggested that Eucalyptus plantations take advantage of soil fertility inherited from previous land uses and that long-term sustainability will require an increase in the inputs of certain nutrients.     

Effects of Urban Sewage on Dissolved Oxygen,Dissolved Inorganic and Organic Carbon,and Electrical Conductivity of Small Streams along a Gradient of Urbanization in the Piracicaba River Basin

In Brazil most of the urban sewage is dumped without treatment into rivers. Because of this, it is extremely important to evaluate the consequences of organic matter rich sewage on the structure and functioning of river ecosystems. In this study we investigated the effects of urban sewage on the dissolved oxygen (O₂), dissolved inorganic (DIC) and organic carbon (DOC), and electrical conductivity (EC) in 10 small streams of the Piracicaba River basin, southeast region of Brazil. In the Piracicaba River basin, which is one of the most developed regions of the country, only 16% of the total sewage load generated is treated. These streams were classified into two groups, one with heavy influence of urban sewage and another with less influence. Both concentrations and seasonal variability were distinct between the two groups. The streams that received sewage effluent had a combination of low O₂ with high DIC, DOC, and EC. In the polluted streams, concentrations of dissolved carbon forms and EC were higher and O₂ concentration lower during the low water period. In the less polluted streams seasonal variations in concentrations were small. We also investigated the efficiency of a sewage treatment plant installed two years ago in the catchment of one of these streams. It was observed an increase in the O₂ concentration after the beginning of the treatment, and a decrease of DIC and DOC concentrations especially during the low water period. However, no significant change was observed in the EC, suggesting that the concentrations of major ions is still unaltered, and that a secondary treatment is necessary in order to reduce ion load into the stream.