A spatiotemporal regression-kriging model for space-time interpolation: a case study of chlorophyll-a prediction in the coastal areas of Zhejiang, China

2018 ◽  
Vol 32 (10) ◽  
pp. 1927-1947 ◽  
Author(s):  
Zhenhong Du ◽  
Sensen Wu ◽  
Mei-Po Kwan ◽  
Chuanrong Zhang ◽  
Feng Zhang ◽  
...  
2008 ◽  
Vol 2 (No. 4) ◽  
pp. 123-134 ◽  
Author(s):  
J. Balkovič ◽  
G. Čemanová ◽  
J. Kollár ◽  
M. Kromka ◽  
K. Harnová

The paper introduces a method of digital mapping of spatial distribution of soil typological units. It implements fuzzy k-means to classify the soil profile data (study area from the Považsk&yacute; Inovec Mountains, Slovakia) and regression-kriging with the selected digital terrain and remote sensing data to draw membership maps of soil typological units. Totally three soil typological units were identified: Haplic Cambisols (Skeletic, Dystric), Albic Stagnic Luvisols, and Haplic Stagnosols (Albic, Dystric). We analysed the membership values to these units with respect to terrain and remote sensing data. The membership values appeared as spatially smoothly dependant on the terrain gradients (linearly or exponentially) whereas the residua showed spatial autocorrelation. Based on regression and kriging analyses, the regression-kriging model was successfully deployed to draw raster membership maps. These maps yield coefficients of determination between R<sup>2</sup> = 56% (Albic Stagnic Luvisols) to R<sup>2</sup>= 79% (Haplic Cambisols (Skeletic, Dystric)) when evaluated by cross validation. The grid-based continuous soil map represents an alternative to the classical polygon soil maps and can offer a wide range of interpretations for landscape studies.


2019 ◽  
Vol 47 (7) ◽  
pp. 1168-1190 ◽  
Author(s):  
Sha Li ◽  
Daniel A. Griffith ◽  
Hong Shu

2020 ◽  
pp. 25-28
Author(s):  
XU HUILIN ◽  
CHEN HUIHUI ◽  
ZHOU WEI ◽  
FU JIAJIA

Tidal fats resources is an important resource in coastal areas of China, which shows a trend of dynamic growth. Ratonal development and efectve utlizaton of tdal fats resources can alleviate the contradicton between more people and less land in China, and is of great signifcance to the development of coastal economy and the protecton of ecological environment in China. Taking Yancheng Tidal Flats of Coastal Areas as an example, analyzes the present situaton of development and utlizaton and the existng problems at the present stage. Relying on the existng industrial foundaton, this paper puts forward the development and utlizaton model of strengthening the constructon of port-neighboring industry, towns and ecological leisure tourism on the basis of modern agriculture


Urban Studies ◽  
2020 ◽  
pp. 004209802091641
Author(s):  
Zifeng Chen ◽  
Anthony Gar-On Yeh

The concept of conventional place-based accessibility, despite being well researched, tends to ignore people’s space–time constraints arising from mandatory activities (e.g. work and household duties), which confine people’s potential movement and delimit the accessible opportunities. As people with different socioeconomic statuses may have different space–time constraints even while living in similar locations, using the place-based measures could lead to an underestimation of accessibility inequality. This study applies a space–time measure to unravel the disparities in service accessibility in suburban China. Since the late 1970s, suburbanisation in Chinese cities has fostered income inequality and has elevated other dimensions (e.g. institutional status and gender) of disparity within each income class. Within this context, we conduct a case study of suburban neighbourhoods in Guangzhou, based on the activity diary data derived from a home-based questionnaire survey. Findings indicate that the use of a space–time measure effectively captures the disparities in service accessibility among residents in suburban Guangzhou. On the basis of structural equation modelling, we further identify that certain socioeconomic groups (e.g. high-income residents, public sector workers, local hukou holders, male household heads and welfare housing residents) tend to experience fewer space–time constraints from rigid activities, such as work, commuting and household duties, and are thus more advantaged in accessing service facilities. These findings imply that urban planning should address the space–time perspective to promote equal service access for the highly heterogeneous social groups in suburban China and to incorporate time-sensitive policies (e.g. flexitime policies).


2010 ◽  
Vol 67 (8) ◽  
pp. 1291-1302 ◽  
Author(s):  
Helder Cunha Pereira ◽  
Norman Allott ◽  
Catherine Coxon

This paper compares, for the first time, nutrient levels and chlorophyll a measured in a set of seasonal lakes with those reported for permanent lakes in the literature. Twenty-two turloughs (karstic seasonal lakes) in western Ireland were sampled monthly from the onset of flooding (October) until they dried out (6 to 9 months). The turloughs showed similar levels of nutrients and chlorophyll a to those reported for Irish and international lakes. Chlorophyll a peaked between November and February in the majority of turloughs, sometimes with values higher than those measured in mesotrophic lakes in summer. A significant log-linear regression was found between total phosphorus and chlorophyll a, which suggests P limitation of algal biomass in the majority of the turloughs. The regression characteristics were not significantly different than those described in similar studies of permanent lakes. Patterns in seasonal variation of nutrients are also presented, their underlying causes being discussed in relation to their transport within catchments. Our results show that despite being predominantly winter phenomena, turloughs can be as productive as permanent lakes.


2012 ◽  
Vol 40 (5) ◽  
pp. 484-500 ◽  
Author(s):  
Cyril Tissot ◽  
David Brosset ◽  
Laurent Barillé ◽  
Laurent Le Grel ◽  
Ion Tillier ◽  
...  

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