The general approach to drought regionalisation regards the multi-year average values of drought indexes as regionalisation indicators, without taking long-term variability into account. This type of ...regionalisation is known as static regionalisation, or mean regionalisation, and does not consider possible variations over multiple years. In order to analyse the probability of climate aridity and drought, in this study, we firstly introduce the novel concept of a probabilistic aridity index for climate regionalisation and a drought index for drought risk regionalisation, as well as a methodology for estimating the frequency of the probabilistic aridity and drought index. Details of the approach used in the regionalisation of aridity and drought risk, and its associated characteristics, are then discussed. Finally, the value of our approach is demonstrated in China. The result shows that climate and drought risk regionalisation is able to provide enriched aridity and drought probability information compared with general climate and drought regionalisation, and can thus provide enhanced technical support for the rational allocation of water resources and the prevention and mitigation of drought disasters.
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•A novel concept of probabilistic aridity and drought index for climate and drought risk regionalisation were proposed.•An approach for regionalisation of aridity and drought risk considering probability were developed.•The value of the regionalisation of drought risk was demonstrated in China.
The programme of identification, cataloguing and evaluation of Polish landscapes, part of the implementation of the European Landscape Convention, has caused an increase in interest in ...physico-geographical regionalisation over recent years. The commonly accepted regionalisation of Poland developed by J. Kondracki (Kondracki & Richling 1994) is sufficient for work at an overview scale (e.g. 1:500,000), whereas its spatial accuracy is too low to make use of it for the purpose of Polish landscape cataloguing. The aim of this article is to present a more up-to-date and detailed division of Poland into mesoregions, adjusted to the 1:50,000 scale. In comparison with older work, the number of mesoregions has increased from 316 to 344. In many cases, some far-reaching changes in meso- and macroregions were made. Nevertheless, in most cases the previous system of units was maintained, with more detailed adjustment of boundaries based on the latest geological and geomorphological data and the use of GIS tools for the DEM analysis. The division presented here is a creatively developing new work aligning the proposals of the majority of Polish researchers. At the same time, it is a regionalisation maintaining the idea of the work developed by J. Kondracki as well as his theoretical assumptions and the criteria used to distinguish units, which makes it a logical continuation of his regional division.
The rapid development in NIR and information technologies saw the development of various initiatives that have generated large scale databases of soil spectroscopy globally. Models generated within a ...specific spectral or geographical domain should be carefully used in other contexts since they may lose their validity. This includes the application of a global, continental or national spectral libraries to local areas or regions. Both, global and local models are valuable and, ideally, we would like to transfer some of the rules learnt by the more general global models to a local domain. In machine learning, the process of sharing intra-domain information is known as transfer learning. This paper aims to describe and evaluate the effectiveness of transfer learning to “localise” a general soil spectral model. The transfer process consists in, first, training a model with a big volume of data covering a diverse group of cases. Second, some layers of the trained neural network are used to build a local model, which is fine-tuned by using a smaller amount of local data. We demonstrated this method using the LUCAS database, an European dataset, comprising spectral data from 21 countries. For each country, we generated three models: a) Global, with data from all except the country of interest; b) Local, with data from the country; and c) Transfer, pre-trained as the Global model and fine-tuned with data from the country. The results showed that the Transfer model can lower the error (expressed as RMSE) 91% of the cases, with a mean reduction of RMSE: 10.5, 11.8, 12.0 and 11.5% for organic carbon, cation exchange capacity, clay content and pH, respectively. This paper demonstrates the usefulness of transfer learning for soil spectroscopy, which will enhance the use of global spectral libraries for local application.
•The method is capable of transferring knowledge from a continental calibration model to generate a localised model.•The method performs better than a global or local model individually.•There was a reduction of the RMSE in 91% of the cases.•The mean reduction was 10.5, 11.8, 12.0 and 11.5% for organic carbon, CEC, clay content and pH.•With this method, collaboration can be beneficial for everyone, including the data-rich countries or organisations.
•Synthesis of nine previous regionalisations of the epipelagic Mediterranean Sea.•Nine congruent frontiers, related to circulation and bathymetry.•Eleven congruent homogeneous regions, related to ...large scale circulation.•Four heterogeneous regions, associated with dynamical mesoscale circulation.•A key step for future spatial planning in scientific studies and marine management.
Regionalisation aims at delimiting provinces within which physical conditions, chemical properties, and biological communities are reasonably homogeneous. This article proposes a synthesis of the many recent regionalisations of the open-sea regions of the Mediterranean Sea. The nine studies considered here defined regions based on different, and sometimes complementary, criteria: dynamics of surface chlorophyll concentration, ocean currents, three-dimensional hydrological and biogeochemical properties, or the distribution of organisms. Although they identified different numbers and patterns of homogeneous regions, their compilation in the epipelagic zone identifies nine consensus frontiers, eleven consensus regions with relatively homogeneous conditions, and four heterogeneous regions with highly dynamical conditions. The consensus frontiers and regions are in agreement with well-known hydrodynamical features of the Mediterranean Sea, which constrain the distribution of hydrological and ecological variables. The heterogeneous regions are rather defined by intense mesoscale activity. The synthesis proposed here could constitute a reference step for management actions and spatial planning, such as the application of the European Marine Strategy Framework Directive, and for future biogeochemical and ecological studies in the Mediterranean Sea.
This study seeks to map out the regionalisation patterns of the world’s largest and most efficient multinationals against regional market characteristics. Re-examining the findings in the ...regionalisation–globalisation literature that show a general bias among firms towards home region markets, this cross-sectional study determines that home market size and home regional market concentrations heavily influence emergent regionalisation patterns. Implications on theory-building within the sphere of the regionalisation–globalisation debate are explored, with a particular focus on measure development.
Shenzhen City in Southeast China has developed from a small fishing village into a modern metropolis since China adopted an open-door policy in 1978. In accordance with its national plan and ...strategy, China has been striving to develop its international Guangdong–Hong Kong–Macau Greater Bay Area (GBA). Owing to its rapidly developing economy, industries and innovative technologies, Shenzhen is an important city in the GBA. Shenzhen’s higher education (HE) is supposedly crucial for its advancement as an innovation hub. However, the HE in Shenzhen is reportedly not adept with the city’s economic development. Although some Chinese studies have focused on Shenzhen’s HE-related issues, such as integration of and co-operation with the GBA’s policies, not many international studies have assessed how universities can help to ensure overall regional development. Thus, in this study, using Shenzhen’s case in the GBA, we explore the roles of universities in regional development. We review several policy documents and literature based on the glonacal framework to collect relevant data in text and generated themes. The study findings address the critical roles of Shenzhen universities in regional development such as promoting research capacity, fostering international collaboration and upgrading the GBA’s HE sector.
•Continuous simulation for regionalization.•Large sample dataset with high differences in terms of catchment properties.•Several alternative objective functions for calibration purposes and ...regionalization strategy were tested.
Flood frequency analysis lies at the core of hydrology and water engineering as one of the most required estimates for water planning and design of hydraulic structures. For ungauged basins, where no information is available, various flood regionalisation techniques have varying degrees of complexity and resulting performance, depending on the study's goal, the region analysed, and the information available. This study evaluates the use of hydrological models for flood regionalisation in Chile, using 1) A large sample dataset of 101 catchments; 2) the continuous simulation approach with the GR4J model; 3) the leave-one-out strategy for performance testing; and, 4) two regionalisation methods: Nearest Neighbour (NN) and Physical Similarity (PS), together with several alternative objective functions for calibration purposes and regionalisation strategy (in all cases adopting a single criterion, single variable and determinist approach for the parameter’s selection). Our results showed that performance (both in calibration–validation and regionalisation) is highly variable (in terms of reproducing the runoff hydrograph and flood statistics), depending on the catchment’s aridity (e.g., around 66–82% of catchments with NSE above 0 in humid regions but it severely drops to 12–44% of catchments with NSE above 0 when evaluating arid catchments). We also found that flood-specific calibration strategies produce better results for floods but poorer performance in runoff hydrograph reproduction. Finally, we highlight that our regionalisation results were in close agreement with those from one of the currently recommended methods by Chilean engineering for flood regionalisation. This is particularly promising, considering that the continuous simulation approach gives access to the complete time series and not only flood statistics. We end this manuscript by discussing several sources of uncertainty, hoping that these can be accounted for in future studies.
Location factors are vital elements for describing housing price variation. However, limited studies have explicitly illustrated the relationship between urban design and the heterogeneity of housing ...price patterns. This article specifically evaluates how the interactions between the spatial layouts and land-use system at various scales through street network affect the valuation of the residential properties and the segmentation of housing markets in a network-based Mixed-scale Hedonic Model (MHM) where the submarkets pattern are determined and annotated by the spatially varying estimates on streets. The application of the delivered method in the case of Shanghai City, China, confirms the necessity of using the non-Euclidean distance metric and represent the coexistence between the stationarity and the non-stationarity of the introduced street accessibility variables. The results provide evidence that the impacts of street accessibility measures on the local levels showcase significant spatial variation. It is common for all the places that the properties located on the streets with the higher levels of angular closeness, smaller values of angular betweenness and longer angular distance to the nearby land-uses at the larger scales will be bided higher. It is proven that our delineation of submarket performs better in prediction accuracy than the traditional submarket specifications. The detected submarkets pattern yields that reachable land-use diversity at the pedestrian level is not a preferred factor in the housing submarkets located in the developed city centres. The signs of the price effects of the angular distance to local land-uses distinguish the developing submarkets as two main groups with different degrees of geometrical walkability. It is suggestive that continuously developing pedestrian-oriented neighbours in the walkable areas could contribute to decelerating the growth of house price in Chinese cities. The productions of this study can enrich the understanding of the socioeconomic effects of urban design with greater spatial precision across submarkets.
•Network distance metric is adopted to calibrate the mixed-scale geographically weighted hedonic model.•Stationarity and non-stationarity of the price effects of the network accessibility variables coexist.•The non-static spatio-functional interplay can be used to delineate reasonable submarkets on streets.•Designing walkable neighbourhoods continuously can decelerate the growth of house price in the developing submarkets.•The introduced approach helps to ensure the economic effects of urban design with greater spatial precision.
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