Sentinel-2/MSI and Landsat-8/OLI sensors enable the mapping of ocean color-related bio-optical parameters of surface coastal and inland waters. While many algorithms have been developed to estimate the Chlorophyll-a concentration, Chl-a, and the suspended particulate matter, SPM, from OLI and MSI data, the absorption by colored dissolved organic matter, a_cdom, a key parameter to monitor the concentration of dissolved organic matter, has received less attention. Herein we present an inverse model (hereafter referred to as AquaCDOM) for estimating a_cdom at the wavelength 412 nm (a_cdom (412)), within the surface layer of coastal waters, from measurements of ocean remote sensing reflectance, R_rs (λ), for these two high spatial resolution (around 20 m) sensors. Combined with a water class-based approach, several empirical algorithms were tested on a mixed dataset of synthetic and in situ data collected from global coastal waters. The selection of the final algorithms was performed with an independent validation dataset, using in situ, synthetic, and satellite R_rs (λ) measurements, but also by testing their respective sensitivity to typical noise introduced by atmospheric correction algorithms. It was found that the proposed algorithms could estimate a_cdom (412) with a median absolute percentage difference of ~30% and a median bias of 0.002 m⁻¹ from the in situ and synthetic datasets. While similar performances have been shown with two other algorithms based on different methodological developments, we have shown that AquaCDOM is much less sensitive to atmospheric correction uncertainties, mainly due to the use of band ratios in its formulation. After the application of the top-of-atmosphere gains and of the same atmospheric correction algorithm, excellent agreement has been found between the OLI- and MSI-derived a_cdom (412) values for various coastal areas, enabling the application of these algorithms for time series analysis. An example application of our algorithms for the time series analysis of a_cdom (412) is provided for a coastal transect in the south of Vietnam.

“Cleaner production “ (CP) emerged in the aftermath of the 1987 Brundtland Commission (WCED, 1987) call for less and more efficient energy and materials use efficiency and the suggestion to substitute more harmful products (for the environment and health) by less dangerous ones. Cleaner production was the reply of industry to the inter-sectorial and socio-economic call for sustainable development. The technical aims widened. Originally they were targeted to improve environmentally inferior products to less inferior ones. Today the goal is producing is quality products using renewable energy efficiently and producing zero waste, while emitting no pollution. The perspective of the scope also changed from environmental sustainability to the wider “Corporate Social Responsibility” (CSR). This includes that post modern companies have not only responsibilities on their economic performance and the environment, but should also act on issues including human rights and resources, business ethics, and community involvement. This widening of contents necessitates more and better adapted methods. During the past 45years the number of assessment methods (preventing pollution and its effects) increased significantly from environmental aspects (EIA), over health (HIA) and policy aspects (SEA), to sustainability assessment, addressing not only environmental, but in an integrated way also social, economic, and ethical issues of the evaluation. This paper reviews this evolution of ideas. It provides not only the concepts, but is equally based on case studies and examples illustrating different aspects of this evolution. It acts as a guide towards contemporary CSR and advocates its support towards education and research. “Producción más limpia” (CP) surgió a raíz de la Comisión Brundtland de 1987 con el objetivo de requerir menos energía y de manera más eficiente con respecto a su uso, sugiriendo sustituir los productos más nocivos (por el medio ambiente y la salud) por menos peligroso; la pro-ducción más limpia, fue la respuesta de la industria a la llamada intersectorial y socioeconómica para el desarrollo sostenible. Los objetivos técnicos se abrieron ya que originalmente estaban dirigidos a mejorar los productos de calidad medioambiental inferior a los menos inferiores. Hoy en día el objetivo es producir productos de calidad utilizando energía renovable eficiente y productoras de residuos cero, mientras que emite ninguna contaminación. Desde la perspectiva del ámbito de aplicación se incorpora la sostenibilidad ambiental a la “Responsabilidad Social Empresarial” más amplia (RSE). Esto incluye que las empresas postmodernas no sólo tienen responsabilidades sobre su desempeño económico y el medio ambiente, sino que también deben actuar en temas como los derechos humanos y los recursos, la ética empresarial, y participación de la comunidad. Esta ampliación de contenidos requiere más y mejor adaptados métodos. Durante los últimos 45 años el número de métodos de evaluación (prevención de la contaminación y sus efectos) aumentó significativamente de los aspectos ambientales (EIA), más de la salud (EIS) y los aspectos de política (SEA), con la evaluación de la sostenibilidad, abordar no sólo el medio ambiente, pero en una también forma integrada social, económica, y las cuestiones éticas de la evaluación. Este documento analiza esta evolución de las ideas, ofreciendo no sólo los conceptos, sino que se basa igualmente en estudios de casos y ejemplos que ilustran diferentes aspectos de esta evolución. Actúa como una guía hacia la RSE contemporánea y aboga por su apoyo hacia la educación y la investigación.

Huong, D.T.T.; Lan, T.D., and Le, D.T., 2024. Environmental conflicts with tourist beach uses along the northeastern Vietnam coast. Journal of Coastal Research, 40(1), 104–114. Charlotte (North Carolina), ISSN 0749-0208. NE Vietnamese beaches possess economic and ecological value, particularly in the areas of international importance, such as the Ha Long Bay World Heritage Site and the Cat Ba Biosphere Reserve, and national significance, such as the National Park of Bai Tu Long Bay. Increasing socioeconomic development in this coastal zone has generated pressures on and use conflicts within coastal ecosystems, including coastal beaches. To support integrated coastal management of the area, identification and in-depth analysis of the environmental conflicts of nine typical tourist beaches were conducted. The conflicts were defined by naming beach users and then grouping them, such as the group of economic sectors and the group of environmentalists and nature conservationists. The first group of beach-use conflicts consists of the conflict of tourism and urbanization with sand mining in Cat Ba, Ha Long–Bai Tu Long, and Cam Pha–Mong Cai; the conflict of tourism and urbanization with marine and coastal aquaculture in Cat Ba, Ha Long–Bai Tu Long, and Cam Pha–Mong Cai, and the conflict of sand mining with marine and coastal aquaculture in Cat Ba and Ha Long–Bai Tu Long. The second group of conflicts between socioeconomic development and nature conservation involves the conflicts of all three economic sectors with conservation activities in the Bai Tu Long National Park and the Cat Ba Biosphere Reserve and the conflicts of tourism, urbanization, and marine and coastal aquaculture with nature conservation in the Ha Long Bay World Heritage Site. Conflict aspects were detailed with the nature of the conflict, parties involved, typological classification, and current trends. Analysis of detailed aspects shows that environmental conflicts are still severe and long-lasting, especially in coastal areas with international and national importance. This requires a resolution of integrated coastal management to be developed as soon as possible for the study area.

Different scenarios have been established and simulated based on the Delft3D model to compare and assess the impact of human activities (increased pollutants as oxygen demand, BOD, COD, nutrients, and land reclamation), climate change (rising temperatures, sea level rise), and a combined scenario of human activities and climate change on water quality in the Cat Ba–Ha Long coastal area. The findings quantify the impacts of anthropogenic activities and climate change on the water quality in the study area in 2030 and 2050. During the northeast monsoon and the two transitional seasons, the impact of humans and climate change adversely affects water quality. The impact of climate change is less significant than that of human activities and their combination, which result in a reduction in DO levels of 0.02–0.13 mg/L, 0.07–0.44 mg/L, and 0.09–0.48 mg/L, respectively. Meanwhile, during the southwest monsoon, climate change significantly reduces water quality (0.25–0.31 mg/L), more so than human activities (0.14–0.16 mg/L) and their combined effects (0.13–0.17 mg/L). This may elucidate the fact that the increase in nutrient supply from the river during the southwest monsoon in this region can result in an increase in nutrient levels and biological activity, which, in turn, causes an increase in DO. Additionally, the augmented quantity of DO may partially offset the decrease in DO resulting from climate change. Under the influence of human activities and climate change, the nutrient levels in the area increase, with average values of 0.002–0.033 g/m³ (NO₃⁻), 0.0003–0.034 g/m³ (NH₄⁺), and 0.0005–0.014 g/m³ (PO₄³⁻).

Zoning Marine Disposal to Minimize Environmental Impacts for Dredged Material Management: A Case Study in Hai Phong Port Area, Vietnam