Variations in land surface temperatures in small-scale urban areas in Vietnam during Covid-19 restrictions: Case studies from Da Nang, Hue and Vinh City.

Land surface temperature (LST) is an important variable in urban microclimate research. At the end of 2019, the emergence of Covid-19 pandemic has changed the world in a manner that forced many countries to impose restrictions in human activities. As a measure to prevent the expansion of Covid-19 infections, most of the major cities have entered a prolonged lockdown period and reduction in human activities between the early 2020 and the late 2021.

Nematode's morphometric shifts related to changing environmental conditions in the Mekong estuaries Ba Lai and Ham Luong, Vietnam.

Damming has been reported to give many short-term benefits for local people but also to result in long-term negative impacts on the aquatic ecosystem. The ecological impact of the Ba Lai dam was studied by investigating environmental differences and the response of associated aquatic nematode communities (structure and morphometric characteristics) in both downstream and upstream sections of its estuary in comparison to an adjacent dam-free estuary Ham Luong, both belonging to the Mekong delta in Vietnam. Depleted dissolved oxygen, elevated methane and sulfide concentrations and increased accumulation of contaminants, including total suspended solid, heavy metals, and nutrients in the dammed estuary and its upstream section, indicated an impact of the dam on the environment.

Diversity and Distribution of Fiddler Crabs (Crustacea: Brachyura: Ocypodidae) in Vietnam.

Based on recently collected material and records in the literature, 14 species of fiddler crabs (Crustacea: Ocypodidae: Gelasiminae) are reported from Vietnam. DNA barcoding analyses using the mitochondrial gene (cytochrome oxidase subunit I) was performed to identify examined materials and their precise distributional range. Thirteen species-level taxa are identified and, with the exception of and , have minimum interspcific divergences of at least 7.

Impact of a dam construction on the intertidal environment and free-living nematodes in the Ba Lai, Mekong Estuaries, Vietnam.

The impact of high siltation and accumulation of organic and waste material in the intertidal of the dammed Ba Lai River in Vietnam as part of the Mekong estuarine system was investigated by means of marine free-living nematodes. Nutrients content (nitrate, ammonium, total phosphorus, total nitrogen), total suspended solids, total organic carbon, coliform, bacteria E. coli, pH, dissolved oxygen, total dissolved solids, methane and hydrogen sulfide concentration, and the nematode communities were characterized in sediment at selected stations along the river above and below the dam.

Seasonal changes in phytoplankton assemblages and environmental variables in highly turbid tropical estuaries of the Mekong River, Vietnam.

The distribution of phytoplankton assemblages in response to physicochemical variables was assessed using Spearman's correlation and canonical correspondence analysis in four highly turbid estuaries of the Mekong River (MKR) system in Ben Tre Province, Vietnam. During two surveys (September 2017 and April 2018) at 20 sampling sites, a total of 162 species were recorded, with a dominance of diatoms (> 50%). Phytoplankton abundance varied from 3.

Anthropogenic influences on coastal environmental changes in the Mekong Delta: a study from Ben Tre Province, Southern Vietnam.

Low-lying coastal environments are highly dynamic and sensitive to natural as well as anthropogenic perturbations. Climate change, sea level rise, storms and tsunamis are the natural phenomena that affect the deltaic coasts in Southeast Asia in general and Vietnam in particular. The effects of these phenomena can be exacerbated by human activities such as mangrove deforestation, aquaculture and infrastructure development.

The effect of a dam on the copper accumulation in estuarine sediment and associated nematodes in a Mekong estuary.

Dam construction across the main flow of an estuary can greatly contribute to a high accumulation of inorganic contaminants. However, it remains unknown to what extend externally available heavy metals are incorporated into biota living in those contaminated environments. In this study, the heavy metal copper was investigated both in the sediment and in the tissues of nematodes taken from the subtidal zone in the Ba Lai estuary where a dam is present, and compared with samples from the dam-free Ham Luong estuary, both part of the Mekong Delta.

Fish species composition, diversity, and migration in the Mekong Delta: a study in the Cua Tieu River, Vietnam.

Southern Vietnam, particularly the Mekong Delta, is popular in inland fish species diversity. In this study, fish species diversity across six stations from the estuary to the upstream of Cua Tieu River, which is situated in the Tien Giang province in Southern Vietnam, has been studied from January 2018 to June 2020. Altogether, 2088 specimens were collected and classified, and these belonged to 115 species, 98 genera, and 54 families of 15 orders that were recognized and identified.

Ecological impact assessment of irrigation dam in the Mekong Delta using intertidal nematode communities as bioindicators.

The ecological response of nematode communities to dam construction has limited attention. In this study, the response of intertidal nematode communities in the Ba Lai River (Mekong Delta, Vietnam) to the construction of an irrigation dam was investigated. Nematode communities and environmental parameters were investigated during the rainy season of 2015.

Impact of biomass burnings in Southeast Asia on air quality and pollutant transport during the end of the 2019 dry season.

At the end of the dry season, March and April in Southeast Asia (SEA), agricultural refuse burnings occur over the region, mainly in the countries of Myanmar, Thailand, Laos, Cambodia and Vietnam, in preparation for the wet rice plantation. In this study, the impact of biomass burnings at the height of the burning period in March 2019 in mainland SEA on air quality and pollutant transport is modelled using the Weather Research Forecast WRF-Chem air quality model with emission input from the National Center for Atmospheric Research (NCAR) Fire Emission Inventory from NCAR (FINN). FINN is derived from satellite remote sensing data and species emission factors.

First molecular examination of Vietnamese mudflat snails in the genus Naranjia Golding, Ponder & Byrne, 2007 (Gastropoda: Amphibolidae).

Maritime ecosystems in Vietnam such as mangroves and mud flats are characterized by high biodiversity. However, elements of its biodiversity remain unclear and highly threatened. In this context, the assessment of rare species is a starting point to develop effective strategies for the conservation of entire ecosystems.

Systematic revision of the genus Fleming, 1822 (Gastropoda, Euthyneura, Pulmonata, Onchidiidae).

The genus Fleming, 1822 includes all the onchidiid slugs with dorsal gills. Its taxonomy is revised for the first time based on a large collection of fresh material from the entire Indo-West Pacific, from South Africa to Hawaii. Nine species are supported by mitochondrial (COI and 16S) and nuclear (ITS2 and 28S) sequences as well as comparative anatomy.

Modelling and prediction of air pollutant transport during the 2014 biomass burning and forest fires in peninsular Southeast Asia.

During the dry season, from November to April, agricultural biomass burning and forest fires especially from March to late April in mainland Southeast Asian countries of Myanmar, Thailand, Laos and Vietnam frequently cause severe particulate pollution not only in the local areas but also across the whole region and beyond due to the prevailing meteorological conditions. Recently, the BASE-ASIA (Biomass-burning Aerosols in South East Asia: Smoke Impact Assessment) and 7-SEAS (7-South-East Asian Studies) studies have provided detailed analysis and important understandings of the transport of pollutants, in particular, the aerosols and their characteristics across the region due to biomass burning in Southeast Asia (SEA). Following these studies, in this paper, we study the transport of particulate air pollution across the peninsular region of SEA and beyond during the March 2014 burning period using meteorological modelling approach and available ground-based and satellite measurements to ascertain the extent of the aerosol pollution and transport in the region of this particular event.

Intertidal nematode communities in the Mekong estuaries of Vietnam and their potential for biomonitoring.

Nematode communities in eight Mekong estuaries were investigated during the dry season. The aim of the study was to identify the structure and the diversity of the communities in relation to the main environmental characteristics. In each estuary, three to four intertidal sampling stations were identified at regular distances from the mouth to up to 45 km land inward.