Beschreibung: Purpose   Managing declining nutrient use efficiency in crop production has been a global priority to maintain high agricultural productivity with finite non-renewable nutrient resources, in particular phosphorus (P). Rapid spectroscopic methods increase measurement density of soil nutrients and improve the accuracy of rates of additional P inputs. Materials and methods   Soil P was measured by a multi-element energy-dispersive X-ray fluorescence spectroscopic (XRFS) method to estimate the spatial distribution of soil total (XRFS-P) and bioavailable P in a Fluvisol occurring on a 20-ha contiguous area comprised of seven elongated field strips under a wheat–maize rotation near the Quzhou Agricultural Experiment Station in the North China Plain. Results and discussion   Soil XRFS-P was highly variable along the length of the field strips and across the entire area after decades of continuous cultivation. A linear relationship existed between XRFS-P and bicarbonate-extractable P or Mehlich 3-extractable P, allowing a description of the spatial distribution of bioavailable P based on XRFS, in both directions of a two-dimensional grid covering the entire area ( p  〈 0.05). Distinct management zones were identified for more precise placement of additional P. Conclusions   Direct element-specific analysis and a high sample throughput make XRFS an indispensable component of a new approach to sustainably manage P, and other macronutrients of low atomic number Z such as K, Ca, or Cl in production fields, based on their site-specific variations in the soil. Concerning P, this rapid precision approach provides a promising avenue to manage soil P as a regionalized variable while preventing zones of deficiency or surplus P that can affect plant productivity or potential loss from a field, respectively. Content Type Journal Article Pages 1-12 DOI 10.1007/s11368-011-0347-2 Authors Thanh H. Dao, USDA-ARS Environmental Management and ByProducts Utilization Laboratory, BARC-East Bldg. 306, Beltsville, MD 20705, USA Yuxin X. Miao, College of Resources and Environmental Science, China Agricultural University, Beijing, People’s Republic of China Fusuo S. Zhang, College of Resources and Environmental Science, China Agricultural University, Beijing, People’s Republic of China Journal Journal of Soils and Sediments Online ISSN 1614-7480 Print ISSN 1439-0108

Beschreibung:    In recent years, owing to global warming and the rising sea levels, beach nourishment and groin building have been increasingly employed to protect coastal land from shoreline erosion. These actions may degrade beach habitats and reduce biomass and invertebrate density at sites where they were employed. We conducted an eco-environmental evaluation at the Anping artificial beach-nourishment project area. At this site, sand piles within a semi-enclosed spur groin have been enforced by use of eco-engineering concepts since 2003. Four sampling sites were monitored during the study period from July 2002 to September 2008. The environmental impact assessment and biological investigations that we conducted are presented here. The results from this study indicate that both biotic (number of species, number of individual organisms, and Shannon-Wiener diversity) and abiotic parameters (suspended solids, biological oxygen demand, chemical oxygen demand, dissolved inorganic nitrogen, dissolved inorganic phosphorus, total phosphorus, total organic carbon, median diameter, and water content) showed significant differences before and after beach engineering construction. Biological conditions became worse in the beginning stages of the engineering but improved after the restoration work completion. This study reveals that the composition of benthic invertebrates changed over the study period, and two groups of organisms, Bivalvia and Gastropoda, seemed to be particularly suitable to this habitat after the semi-enclosed artificial structures completion. Content Type Journal Article Pages 215-236 DOI 10.1007/s13344-011-0019-4 Authors Chun-Han Shih, Institute of Fisheries Science, National Taiwan University, Taipei, 10617 China Yi-Yu Kuo, Department of Civil Engineering, National Chiao Tung University, Hsinchu, 30010 China Ta-Jen Chu, Department of Leisure and Recreation Management, Chung Hua University, Hsinchu, 30012 China Wen-Chieh Chou, Department of Civil Engineering, Chung Hua University, Hsinchu, 30012 China Wei-Tse Chang, Institute of Fisheries Science, National Taiwan University, Taipei, 10617 China Ying-Chou Lee, Institute of Fisheries Science, National Taiwan University, Taipei, 10617 China Journal China Ocean Engineering Print ISSN 0890-5487 Journal Volume Volume 25 Journal Issue Volume 25, Number 2