3 research outputs found
Soil Quality - a critical review
Sampling and analysis or visual examination of soil to assess its status and use potential is widely practiced from plot to national scales. However, the choice of relevant soil attributes and interpretation of measurements are not straightforward, because of the complexity and site-specificity of soils, legacy effects of previous land use, and trade-offs between ecosystem services. Here we review soil quality and related concepts, in terms of definition, assessment approaches, and indicator selection and interpretation. We identify the most frequently used soil quality indicators under agricultural land use. We find that explicit evaluation of soil quality with respect to specific soil threats, soil functions and ecosystem services has rarely been implemented, and few approaches provide clear interpretation schemes of measured indicator values. This limits their adoption by land managers as well as policy. We also consider novel indicators that address currently neglected though important soil properties and processes, and we list the crucial steps in the development of a soil quality assessment procedure that is scientifically sound and supports management and policy decisions that account for the multi-functionality of soil. This requires the involvement of the pertinent actors, stakeholders and end-users to a much larger degree than practiced to date
Investigating of a three-mirror multipass waveguide laser resonator for a compact CO2 laser with radio frequency pumping
Phosphorus (P) is an essential element for all living organisms. At the current rate of extraction, global reserves of mineable deposits will be exhausted within the next few centuries. This publication aims to summarize the current knowledge on P recycling for organic farming. The evaluation of recycled P fertilizers (RPFs) includes (i) a chemical characterization, (ii) assessment of their plant P availability and added effects in the soil, (iii) life cycle assessments, (iv) a risk assessment of their long-term impacts on soil pollution, and (v) the compilation of other environmental impacts of different treatment approaches to produce RPFs.The highest nutrient recovery rates for P are achieved by rather simple process approaches of P recycling, while more sophisticated approaches often result in lower P recovery rates (e.g., chemical approaches for P precipitation), lower plant P availability in the final product (e.g., most thermal approaches), and losses of organic matter and nutrients like nitrogen and sulfur (e.g., thermal approaches). The plant P availability of many RPFs is higher than that of phosphate rock. Each P recycling approach has strengths and weaknesses. We conclude that any decision not to use a potential recycled P source or to introduce sophisticated treatments may have consequences compromising the ability of future generations to meet their needs. Nevertheless, we need to minimize risks for current and future generations caused by contamination linked to fertilization. Therefore, any management of nutrient recycling requires navigation between constraints. The challenge for the organic agriculture sector is to assess RPFs using a balanced approach that compromises neither the principle of ecology nor the principle of care
Soil Quality - a critical review
Sampling and analysis or visual examination of soil to assess its status and use potential is widely practiced from plot to national scales. However, the choice of relevant soil attributes and interpretation of measurements are not straightforward, because of the complexity and site-specificity of soils, legacy effects of previous land use, and trade-offs between ecosystem services. Here we review soil quality and related concepts, in terms of definition, assessment approaches, and indicator selection and interpretation. We identify the most frequently used soil quality indicators under agricultural land use. We find that explicit evaluation of soil quality with respect to specific soil threats, soil functions and ecosystem services has rarely been implemented, and few approaches provide clear interpretation schemes of measured indicator values. This limits their adoption by land managers as well as policy. We also consider novel indicators that address currently neglected though important soil properties and processes, and we list the crucial steps in the development of a soil quality assessment procedure that is scientifically sound and supports management and policy decisions that account for the multi-functionality of soil. This requires the involvement of the pertinent actors, stakeholders and end-users to a much larger degree than practiced to date