This study was carried out to understand how land use patterns influence surface water quality in Tien Giang Province using remote sensing and statistical approaches. Surface water quality data were collected at 34 locations with the frequency of four times (March, June, September, and November) in 2019. Water quality parameters were used in the analysis, including pH, temperature, electrical conductivity (EC), total suspended solids (TSS), dissolved oxygen (DO), biological oxygen demand (BOD), chemical oxygen demand (COD), ammonium (N-NH₄⁺), nitrite (N-NO₂⁻), nitrate (N-NO₃⁻), sulfate (SO₄²⁻), orthophosphate (P-PO₄³⁻), chloride (Cl⁻), total nitrogen (TN), total phosphorus (TP), and coliform. The relationship between land use patterns and water quality was analyzed using geographic information techniques (GIS), remote sensing (RS), statistical approaches (cluster analysis (CA), principal component analysis (PCA), and Krustal–Wallis), and weighted entropy. The results showed water quality was impaired by total suspended solids, nutrients (N-NH₄⁺, N-NO₂⁻, P-PO₄³⁻), organic matters (BOD, COD), and ions (Cl⁻ and SO₄²⁻). Kruskal–Wallis analysis results showed that all water quality parameters in the water bodies in Tien Giang Province were seasonally fluctuated, except for BOD and TN. The highest levels of water pollutants were found mostly in the dry season (March and June). The majority of the land in the study area was used for rice cultivation (40.64%) and residential (27.51%). Water quality in the study area was classified into nine groups corresponding to five combined land use patterns comprising residential–aquaculture, residential–rice cultivation, residential–perennials, residential–rice–perennial, and residential–rice–perennial crops–aquacultural. The concentrations of the water pollutants (TSS, DO, BOD, COD, N-NH₄⁺, N-NO₂⁻, Cl⁻, and coliform) in the locations with aquaculture land use patterns (Clusters 1 and 2) were significantly larger than those of the remaining land use patterns. PCA analysis presented that most of the current water quality monitoring parameters had a great impact on water quality in the water bodies. The entropy weight showed that TSS, N-NO₂⁻, and coliform are the most important water quality parameters due to residential–aquaculture and residential–rice cultivation; EC, DO, N-NH₄⁺, N-NO₂⁻, Cl⁻, and coliform were the significant variables for the land use type of residential–perennial crops; N-NO₂⁻, P-PO₄³⁻, and coliform for the land use pattern of residential–rice cultivation–perennial crops) and N-NH₄⁺, N-NO₂⁻, Cl⁻, and coliform for the land use pattern of residential–rice cultivation–perennial crops–aquaculture. The current findings showed that that surface water quality has been influenced by the complex land use patterns in which residential and rice cultivation may have major roles in causing water impairment. The results of the water quality assessment and the variation in water properties of the land use patterns found in this study provide scientific evidence for future water quality management.

Biogas digestive effluent (BDE) is a nutrient-enriched source that can be utilized as an organic fertilizer for rice cultivation without synthetic fertilizer (SF) application. However, a primary concern is the stimulation of methane (CH₄) emissions due to the enrichment of the labile organic carbon, a favorite substrate of methanogenic archaea. Methanotrophs potentially reduce greenhouse gas (GHG) emissions from rice fields owing to metabolizing CH₄ as a carbon source and energy. We therefore examined the effect of the application of methanotroph-inoculated BDE to the rice cultivated paddy soil on GHG emissions and rice productivity under a pot experiment. Methanotrophs (Methylosinus sp. and Methylocystis sp.), isolated from the Vietnamese Mekong Delta’s rice fields, were separately inoculated to the heated BDE, followed by a 5-day preincubation. Methanotroph-inoculated BDE was supplied to rice cultivation to substitute SF at 50% or 100% in terms of nitrogen amount. The results showed that the total CH₄ emissions increased ~34% with the application of BDE. CH₄ emissions were significantly reduced by ~17–21% and ~28–44% under the application of methanotroph-inoculated BDE at 100% and 50%, respectively. The reduction in CH₄ was commensurate with the augmentation of pmoA transcript copy number under methanotroph-inoculated BDE. In addition, methanotroph-inoculated BDE application did not increase nitrous oxide (N₂O) emissions and adversely affect rice growth and grain productivity. This study highlighted the BDE-recirculated feasibility for a lower CH₄ emission rice production based on methanotrophs where high CH₄-emitting fields were confirmed.

This study evaluated the biogas production potential of water lettuce (Pistia stratiotes L.) by batch anaerobic digestion under in-vitro conditions. Twenty-one litre-plastic jars were used to conduct 4 replications over 75 days. The results showed that solution temperature, pH and Eh were...

Mangrove forest protection is an essential solution for mitigating the impacts of natural disasters in coastal zones and climate change. Integrated mangrove-shrimp fanning (IMSF) system has been promoted as a sustainable livelihood that can provide income for farmers and protect mangrove forests. However, the productivity of shrimp is limited. Therefore, to enhance the revenue for farmers, improving the value of shrimp products is a good option. Organic shrimp fanning practices following the EU aquaculture organic standards have been previously applied in some areas of the Mekong delta. This study was conducted to compare technical, financial characteristics and environmental parameters between the applied (i.e., organic farms) and non-applied (i.e., non-organic farms) standards of Naturland, aiming to support the development of ecological shrimp farming and contribute towards green development. The study was carried out in Nhung Mien mangrove forest, Ngoc Hien district, Ca Mau province, Vietnam. Fifty organic farms and 50 non-organic farms were directly interviewed using structured questionnaires. And then, three farms in each system were selected for monitoring water quality. Results showed that the average mangrove coverage was 54.1% in the organic IMSF system and significantly different from the non-organic IMSF system (p<0.05). Total shrimp yield, total income and total profits tended to increase in organic IMSF system and the selling shrimp price increased by 10% compared to the conventional price. The study showed that following organic fanning methods could provide higher income for farmers and a better chance to mitigate natural disasters and climate change impacts.