In spatial interpolation, one of the most widely used deterministic methods is the inverse distance weighting (IDW) technique. The general idea of IDW is primarily based on the hypothesis that the attribute value of an ungauged site is the weighted average of the known attribute values within the neighborhood, and the ‘weights’ are merely associated with the horizontal distances between the gauged and ungauged sites. However, here we propose an extended version of IDW (hereafter, called the EIDW method) to provide ‘alternative weights’ based on the blended geographical and physiographical spaces for estimation of streamflow percentiles at ungauged sites. Based on the leave-one-out cross-validation procedure, the coefficient of determination had a value of 0.77 and 0.82 for the proposed EIDW models, M1 and M2, respectively, with low root mean square errors. Moreover, after investigating the relationship between the prediction efficiency and the distance decay parameter (C), the better performance of the M1 and M2 resulted at C = 2. Furthermore, the results of this study show that the EIDW could be considered as a constructive way forward to provide more accurate and consistent results in comparison to the traditional IDW or the dimension reduction technique-based IDW.
Bell Brothers – showcasing nutrient use efficiency - Case Study
Glasshouse growing conditions are ideal for using natural biostimulants to increase the efficiency of fertiliser programmes. Neil Chambers, Technical Manager at Bell Brother Nurseries Ltd, has been talking to us about his use of seaweed extract Stimplex to help minimise growing times, produce healthier, more resilient plants and reduce chemical inputs. Increasing levels of research into the various beneficial compounds naturally present within Ascophyllum nodosum seaweed, has given us valuable insight into its...
Getting Down to the Roots: Why Soil Matters for Climate Stabilization (and More)
Following 2015’s designation as the International Year of Soils by the UN Food and Agriculture Organization, soil carbon sequestration is experiencing something of a renaissance among policy and scientific circles. Farmers are also getting involved, most recently through the Climate Leaders program of the National Farmers Union. Now the challenge is to translate all this momentum to action, starting with how we approach and develop climate-smart projects. In April 2015, USDA released the Building Blocks of...
Examination of a coupled supply- and demand-induced stress function for root water uptake modeling
Vegetation water use is closely related to its biophysical functioning and is often under stress from various environmental factors. However, commonly used root water uptake models only consider the stress from root zone moisture availability. There is a need to incorporate the stress from both the above-ground factors and root zone water condition. In this study, a newly developed coupled supply- and demand-induced (S&D) root water uptake model is examined with measurements on two tree species, Guihua in the...
Circular economy in Europe — Developing the knowledge base
Europe is bound to the rest of the world through multiple systems that enable two-way flows of materials, financial resources, ideas and innovation. As a result, Europe`s economic, ecological and societal resilience is and will continue to be significantly affected by a variety of global and interdependent social, economic, political, environmental and technological trends. Global material resource use in 2030, for example, is expected to be twice that of 2010 (SERI, 2013), while the most recent United Nations...
Germination and early plant development of ten plant species exposed to TiO2 and CeO2 nanoparticles
Ten agronomic plant species were exposed to different concentrations of nano titanium dioxide (nTiO2) or nano cerium oxide (nCeO2) (0, 250 µg/mL, 500 µg/mL and 1000 µg/mL) to examine potential effects on germination and early seedling development. We modified a standard test protocol developed for soluble chemicals (OPPTS 850.4200) to determine if such an approach might be useful for screening engineered nanomaterials (ENMs) and whether there were differences in response across a range of commercially important...