Evaluating Landsat-8 and Sentinel-2 Data Consistency for High Spatiotemporal Inland and Coastal Water Quality Monitoring

The synergy of fine-to-moderate-resolutin (i.e., 10–60 m) satellite data of the Landsat-8 Operational Land Imager (OLI) and the Sentinel-2 Multispectral Instrument (MSI) provides a possibility to monitor the dynamics of sensitive aquatic systems. However, it is imperative to assess the spectral consistency of both sensors before developing new algorithms for their combined use. This study evaluates spectral consistency between OLI and MSI-A/B, mainly in terms of the topof-atmosphere reflectance (ρt), Rayleigh-corrected reflectance (ρrc), and remote-sensing reflectance (Rrs). To check the spectral consistency under various atmospheric and aquatic conditions, nearsimultaneous same-day overpass images of OLI and MSI-A/B were selected over diverse coastal and inland areas across Mainland China and Hong Kong. The results showed that spectral data obtained from OLI and MSI-A/B were consistent. The difference in the mean absolute percentage error (MAPE) of the OLI and MSI-A products was ~8% in ρt and ~10% in both ρrc and Rrs for all the matching bands, whereas the MAPE for OLI and MSI-B was ~3.7% in ρt , ~5.7% in ρrc, and ~7.5% in Rrs for all visible bands except the ultra-blue band. Overall, the green band was the most consistent, with the lowest MAPE of ≤ 4.6% in all the products. The linear regression model suggested that product difference decreased significantly after band adjustment with the highest reduction rate in Rrs (NIR band) and Rrs (red band) for the OLI–MSI-A and OLI–MSI-B comparison, respectively. Further, this study discussed the combined use of OLI and MSI-A/B data for (i) time series of the total suspended solid concentrations (TSS) over coastal and inland waters; (ii) floating algae area comparison; and (iii) tracking changes in coastal floating algae (FA). Time series analysis of the TSS showed that seasonal variation was well-captured by the combined use of sensors. The analysis of the floating algae bloom area revealed that the algae area was consistent, however, the difference increases as the time difference between the same-day overpasses increases. Furthermore, tracking changes in coastal FA over two months showed that thin algal slicks (width < 500 m) can be detected with an adequate spatial resolution of the OLI and the MSI

Functional constituency members in Hong Kong's Legislative Council : a study of governance, legitimacy and accountability in action / y Cheung Hin Kei, Hankie, Ho Sing Yan, Simon, Li Man Pong, Charles, Tse Tsz Ying, Amy, Wong Man Ting, Mandy

published_or_final_versionPolitics and Public AdministrationMasterMaster of Public Administratio

Spatial analytical methods for deriving a historical map of physiological equivalent temperature of Hong Kong

Lai P-C, Choi CCY, Wong PPY, et al. Spatial analytical methods for deriving a historical map of physiological equivalent temperature of Hong Kong. Building and Environment. 2015;99:22-28

Genome sequence and genetic linkage analysis of Shiitake mushroom _Lentinula edodes_

_Lentinula edodes_ (Shiitake/Xianggu) is an important cultivated mushroom. Understanding the genomics and functional genomics of _L. edodes_ allows us to improve its cultivation and quality. Genome sequence is a key to develop molecular genetic markers for breeding and genetic manipulation. We sequenced the genome of _L. edodes_ monokaryon L54A using Roche 454 and ABI SOLiD genome sequencing. Sequencing reads of about 1400Mb were de novo assembled into a 40.2 Mb genome sequence. We compiled the genome sequence into a searchable database with which we have been annotating the genes and analyzing the metabolic pathways. In addition, we have been using many molecular techniques to analyze genes differentially expressed during development. Gene ortholog groups of _L. edodes_ genome sequence compared across genomes of several fungi including mushrooms identified gene families unique to mushroom-forming fungi. We used a mapping population of haploid basidiospores of dikaryon L54 for genetic linkage analysis. High-quality variations such as single nucleotide polymorphisms, insertions, and deletions of the mapping population formed a high-density genetic linkage map. We compared the linkage map to the _L. edodes_ L54A genome sequence and located selected quantitative trait loci. The Shiitake community will benefit from these resources for genetic studies and breeding.&#xd;&#xa

Temperature change and urbanisation in a multi-nucleated megacity: China’s Pearl River Delta

This paper investigates urbanisation and temperature indices, over four decades in a multi-nucleated megacity, China’s Pearl River Delta (PRD). Daily mean minimum, maximum and mean temperatures (Tmin, Tmax and Tmean) have increased considerably above background warming rates. However, only weak to moderate relationships are observed between trends in local urban surface area surrounding climatic stations, and Tmin used as a proxy for UHI development. While 5 out of 21 stations with high increase in both Tmin and degree of urbanisation, showed moderate relationship (R=0.51), another 8 stations with low urbanisation showed significant increase in Tmin. This suggests warming from factors other than local urban development on Tmin. Since PRD contains 123 cities over 1 million population, and a semi-continuous urbanised area due to merging of urban centres, a regional heat island circulation, or heat dome model is invoked. The observed increase in Tmax above background warming rates for 14 stations, is more difficult to explain as Tmax is not generally affected by urbanisation. This is attributed to high surface energy flux in the afternoon, and anthropogenic energy use in dense urban districts. The regional heat dome circulation over PRD suggests local temperatures will increase further, even without further local developments

Detection of microalbuminuria in non-insulin dependent diabetes mellitus (NIDDM) patients without overt proteinuria by a semiquantitative albumin-creatinine urine strips

AbstractMicroalbuminuria is the hallmark of the reversible stage of incipient diabetic nephropathy. A cost- effective and convenient bedside screening test is essential to detect this phase. We used Clinitek 50® which is a semiquantitative strip test to check spot urine sample from 81 patients with albustix one plus or less. The incidence of Clinitek 50® microalbuminuria was 17%, 18.2% and 75% in 47, 22 and 12 patients with albustix negative, trace or one plus respectively. Nineteen and 13 of the 21 Clinitek 50® positive patients were checked for spot urine DCA 2000® and two 12-hour urine collection for immunoassay respectively. Around 60% of these samples fell into the microalbuminuria range and 40% into the overt albuminuria range by either technique. There was no false positive of Clinitek 50®. The lowest range of microalbuminuria detected by Clinitek 50® was 27 μg/minute (38 mg/day). We concluded that Clinitek 50® is a useful screening test as it is nonexpensive, easily operated and has a sensitivity close to the lower range of microalbuminuria

Detection and Monitoring of Marine Pollution Using Remote Sensing Technologies

Recently, the marine habitat has been under pollution threat, which impacts many human activities as well as human life. Increasing concerns about pollution levels in the oceans and coastal regions have led to multiple approaches for measuring and mitigating marine pollution, in order to achieve sustainable marine water quality. Satellite remote sensing, covering large and remote areas, is considered useful for detecting and monitoring marine pollution. Recent developments in sensor technologies have transformed remote sensing into an effective means of monitoring marine areas. Different remote sensing platforms and sensors have their own capabilities for mapping and monitoring water pollution of different types, characteristics, and concentrations. This chapter will discuss and elaborate the merits and limitations of these remote sensing techniques for mapping oil pollutants, suspended solid concentrations, algal blooms, and floating plastic waste in marine waters

Studying the effect of blue-green infrastructure on microclimate and human thermal comfort in Melbourne’s central business district

Blue-green infrastructure (BGI) is defined as a strategically planned network of natural and semi-natural areas with other environmental features designed and managed to deliver a wide range of ecosystem services, which include microclimate regulation and enhanced human thermal comfort. While green infrastructure is widely known to be capable of mitigating the adverse effects of urban heat island, the effect of blue infrastructure to regulate thermal comfort is still poorly understood. This study investigates several blue-green-infrastructure (BGI) scenarios in the central business district (CBD) of Melbourne, Australia to assess their effects on microclimate and human thermal comfort. Three-dimensional microclimatic modelling software, ENVI-met, was used to simulate the microclimate and human thermal comfort. Physiological equivalent temperature (PET) was used to quantify the level of thermal comfort in selected research areas. Ten different scenarios were simulated, which included those based on green roofs, green walls, trees, ponds and fountains. The simulations suggest that green roofs and green walls in the high-rise building environment have a small temperature reduction in its surrounding area by up to 0.47 °C and 0.27 °C, respectively, and there is no noticeable improvement in the level of thermal perception. The tree-based scenarios decrease temperature by up to 0.93 °C and improve the thermal perception from hot to warm. Scenarios based on water bodies and fountains decrease the temperature by up to 0.51 °C and 1.48 °C, respectively, yet they cannot improve the thermal perception of the area. A deeper water body has a better microclimate improvement as compared to a shallow one. The temperature reduction in the fountain scenario tends to be local and the effect could only be felt within a certain radius from the fountain