В ходе работы были изучены показатели 9 метестанций, расположенных в различных провинциях дельты р. Меконг. Данные, полученные за период 2014–2020 гг., были сопоставлены с показателями 1984–2013 гг. Проведенный анализ показал, что в 2014–2020 гг. средняя темпе- ратура в дельте Меконга составляла +27.6 °C; сумма осадков – 1533.9 мм; средняя влажность – 79% и более; годовая сумма испарения – 942.3 мм; число часов солнечного сияния – 2521. По сравнению с 1984–2013 гг. среднегодовая температура имела тенденцию к повышению, а годовое количество осадков и годовая сумма испарения – к снижению. Оценка тренда изменения метео- параметров с 2014 г. до 202 0г. показала, что средняя температура во время сухого сезона и аб- солютный минимум температуры на всех метеостанциях имели тенденцию к увеличению. Сезон дождей характеризовался увеличением среднесуточных температур, количества осадков, влаж- ности, уменьшением испарения и количества солнечных часов по сравнению с сухим сезоном. Полученные данные о метеорологических характеристиках дельты Меконга станут основой для оценки динамики изменения климата, предоставления исходных данных для других исследований и выработки решений по рациональному использованию климатических ресурсов в целях содей- ствия социально-экономическому развитию этого региона. Meteorological data from 9 weather stations located in different provinces of the Vietnamese Mekong Delta were analyzed and compared in this study. The data analysis showed that in 2014–2020 the average annual temperature in the Mekong Delta was 27.6 °С, the total annual rainfall – 1533.9 mm, the average annual humidity – 79% or more, the total annual evaporation – 942.3 mm, and the total annual sunshine duration – 2521 hours. The average annual temperature in 2014–2020 was higher than that during the 1984–2013 period. Meanwhile, the total annual rainfall and the total annual evaporation in 2014–2020 were lower than that during the 1984–2013 period. Trend analysis of meteorological parameters from 2014 to 2020 showed that the average temperature during the dry season and the absolute minimum temperature at all weather stations tended to increase over time. The rainy season had a higher average daily temperature, more rainfall, and higher humidity, but lower evaporation, and lower sunshine hours than the dry season. The obtained data on the meteorological characteristics of the Vietnamese Mekong Delta lay the foundation for evaluating the dynamics of climate change, providing background for further research and developing solutions for the rational use of climate resources to promote the socio-economic development of this region.
The changes in depth, temperature, water conductivity, and dissolved oxygen concentration in six floodplain lakes are described in regard to the dynamics of spring flooding and overgrowth by macrophytes. The influence of these factors on the composition and structure of macrozoobenthos communities is analyzed. The observed number of species refers to 60% of the theoretically predicted, which allows us to assume that the fauna has been identified sufficiently enough to analyze the interannual changes. Six families of invertebrates, which form together 55% of the fauna, are the richest in species number. The distribution of species by families also confirms enough data on the fauna representing in the obtained and analyzed samples. Abundance of only two species depend significantly on environmental characteristics; the taxonomic and trophic groups exhibit more links to the environment. Totally, 45 mutually associated species (43.7% of the total list) have been identified; they form 8 groups that are characterized by connectivity of the species composition ranging as 0.28–1.0 link/species, the average connectivity strength of 0.67–0.80, and the strength of species connectivity of 0.38–0.84 (the last index is proposed for the first time). Groups of mutually associated species may be defined as “faunistic cores of communities” confined to certain lakes and/or years of study. According to the redundancy analysis with multidimensional scaling ordination, the environmental factors affect the quantitative characteristics and overall taxonomic richness of communities. The indices, describing the structure of communities, do not depend on the analyzed factors, which is also confirmed by correlation analysis.
