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Geeste, Germany

Schellhorn M.,Stephan Schmidt KG | Schenk M.K.,Leibniz University of Hanover | Schmilewski G.,Klasmann Deilmann GmbH | Binner I.,Leibniz University of Hanover | And 5 more authors.
Telma | Year: 2013

The purpose of adding clay to horticultural growing media is to achieve objectives such as a well-balanced nutrient supply, buffering of the pH-value, improvement of the rewettability, cohesion of the growing medium and supply of trace elements. Criteria for choosing clay types for specific applications are necessary to assess the suitability of original materials as well as processed clays in a reliable way. A wide range of clays for different applications was chosen for this study. Differences in the mineralogical composition and in pretreatment of the selected clays resulted in specific physical and chemical characteristics of the different growing media mixes. The influence of different clays on the rewettability and cohesion of growing media was analyzed in laboratory experiments which resulted in the definition of important parameters for selection of clays and suitable methods for processing. Clays with strong K and P fixation as well as clays with spontaneous release of these macronutrients were identified. The effects of clays on the flow of nutrients were documented in crop tests, growth-trials regarding Mn toxicity, carried out with clays with different contents of active Mn, proved that an existing RHP-threshold value for Mn in clays for growing media is not justified. Source

Schmilewski G.,Klasmann Deilmann GmbH
Acta Horticulturae | Year: 2014

Basic traditional knowledge of the characteristics of materials to formulate growing media was common in the past. Choosing growing media constituents and additives for the manufacture of growing media today, requires a much more differentiated approach. Besides knowing the chemical, physical and biological properties of materials and considering general economic aspects, now environmental and social aspects are gaining importance for decision-making. The careful management and scientific evaluation of growing media constituents and production of such media are essential to satisfy the increasing demands of growers, growing media manufacturers, environmental NGOs, governmental bodies, and other stakeholders. In particular the 'peat issue' continues to gain attention in Europe and elsewhere. Debates are often based on biased approaches by any one stakeholder group. The recent comparative life cycle assessment of horticultural growing media based on peat and other growing media constituents, commissioned by the European Peat and Growing Media Association (EPAGMA), clearly shows that all growing media constituents and growing media have an environmental impact. Sustainable development of the growing media and horticulture industries is only feasible when based on a holistic approach when selecting constituents. Source

Kobbing J.F.,Klasmann Deilmann GmbH | Beckmann V.,University of Greifswald | Thevs N.,World Agroforestry Center | Peng H.,University of Greifswald | Zerbe S.,Free University of Bozen Bolzano
Wetlands Ecology and Management | Year: 2015

Common Reed (Phragmites australis) is a wetland plant which is distributed worldwide, has a high biomass production, and provides important ecosystem services. In many developing and emerging countries it is an easily available and cheap raw material for diverse utilization, which may contribute significantly to employment and income generation for the local population. This case study investigates the reed utilization for pulp and paper production at the eutrophic Wuliangsuhai Lake, Inner Mongolia, China. We analysed the fluxes of materials and money along the supply chain (reed harvesting, processing and supply to final users, i.e. paper mills) as well as the division of work and costs at each production layer (network), based on the Netchain theory. The results make evident the importance of the paper industry and reed harvesting for local livelihood. They further reveal that the reed economy at Wuliangsuhai Lake is threatened by rising environmental standards for paper mills, change of market conditions and dependency on only two customers. Increasing revenues by finding new consumers or/and products, come to long-term contracts and improving harvesting efficiency are presented as ways to convert these threats into new opportunities. © 2015 Springer Science+Business Media Dordrecht Source

The peat and substrate industry is under fire for its alleged impact on nature and the climate. In view of this, Klasmann-Deilmann GmbH is taking advantage of the opportunities that result from a sustainability strategy aligned with international standards in order to disclose its own performance to the public under ecological, economic and social criteria. A key element here is the publication of an annual Sustainability Report, of which a climate footprint now forms an integral part. This is the first time that a company in the peat and substrate sector has calculated its emissions from peat extraction and from the production and sale of growing media. The following article outlines the crucial aspects of a corporate policy geared towards sustainability, as this could be ground-breaking for the future of the industry. Source

Dultz S.,Leibniz University of Hanover | Below M.,Leibniz University of Hanover | Walsch J.,Leibniz University of Hanover | Schmilewski G.,Klasmann Deilmann GmbH | And 2 more authors.
Acta Horticulturae | Year: 2013

Peat is an important growing media constituent which exposes hydrophobic properties if getting dry. The addition of clay induces a coated surface with hydrophilic properties which improves the re-wettability. The formation of an effective clay coating on peat during processing depends predominantly on the amount of clay applied, clay fineness and mineral parameters. Peat surfaces consist mainly of C. When these are covered with clay minerals rich in Si, the degree of coverage can be described as the C/Si ratio, determined by energy dispersive X-ray spectroscopy. A moderately decomposed sphagnum peat was amended with four different clays from the Rhenish Massif, Germany (10, 20, and 30 kg clay/m3). Aggregate size varied from <0.063 to 2.0-4.0 mm and water-uptake characteristics were determined using a capillary-rise method. Water uptake was improved for all samples by amendment of clay, strongly depending on clay parameters. At C/Si ratios <20, where the surfaces of peat are most completely coated with clay minerals, all clay-peat systems showed the highest water uptake rate. Saprolitic and translocated clays, consisting mainly of illite and kaolinite, had the strongest effect on surface coverage degree. Here already 20 kg/m3 were sufficient to reach lowest C/Si ratios indicating maximum coverage degree. These clays showed fastest water uptake (50 vol. % within 10 min), whereas bentonite showed only minor effects (1.47 to 3.63 (% v/v)/min). A translocated clay was most effective to improve the water uptake rate, admixing small clay amounts. The results show a good correlation of the C/Si ratio and re-wettability. The determination of the C/Si ratio in a relatively short procedure is a method to estimate the water uptake rate of different horticultural growing media. The combination of these methods can be used to identify suitable clays for improving re-wettability, optimum clay fineness and the amount of clay needed. Source

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