This study documents the ichthyofaunal composition of the Ba River basin in Central Vietnam, recording a total of 182 species across 55 families and 15 orders. Perciformes is the most diverse order (20 families, 36.36%), while Cyprinidae is the most diverse family (24 genera, Northern element accounts for 35.84% of species, the Southern element for 59.43%, and the Mekong element for 71.69%.”21.62%). The genus Osteochilus is the most dominant, represented by 6 species (3.30%). In terms of zoogeographic elements, the Northern element accounts for 35.84% of species, the Southern element for 59.43%, and the Mekong element for 71.69%. Characterized by high taxonomic diversity, the basin functions as a biogeographical transition zone where the South China and Indochinese subregions converge. These findings position the Ba River as a pivotal ecological buffer, mediating the distribution of freshwater fish fauna between the Northern and Southern zoogeographic provinces of Vietnam.

In recent years, water hyacinth (Eichhornia crassipes) has been widely recognized as an invasive aquatic plant that proliferates rapidly on rivers, canals, ponds, and lakes, obstructing waterway transportation, impeding water flow, and contributing to environmental degradation. Despite its abundance in large river systems such as the Bach Dang River in Thu Dau Mot City, Binh Duong Province, this biomass resource remains largely underutilized, leading to significant waste of natural materials and ongoing ecological challenges. This study proposes an eco-friendly alternative by transforming water hyacinth into handmade paper sheets with natural coloration, rustic aesthetic, and complete absence of harmful chemicals. The resulting products exhibit acceptable strength and surface quality, making them suitable for practical and decorative applications including coasters, shoe insoles, greeting cards, notebooks, biodegradable packaging, paper bags, and eco-handicraft items. Raw materials were collected directly from the Bach Dang River by a student research group. The research employed a combination of primary and secondary data collection methods, along with experimental, analytical, and synthesis approaches to develop and evaluate the manual paper-making process. The developed chemical-free production method successfully yielded durable paper sheets that are environmentally safe and biodegradable. The findings demonstrate the feasibility of converting an invasive plant into value-added sustainable products, thereby contributing to waste reduction, biomass reuse, and the promotion of green production practices. Although the study is preliminary and limited by manual processing, lack of mechanization, and absence of standardized quantitative testing (e.g., tensile strength, water absorption, and biodegradability under controlled conditions), it provides a promising foundation for further optimization and scale-up. Future research should focus on improving uniformity, enhancing mechanical properties through natural additives, and conducting comprehensive performance and life-cycle assessments to support practical commercialization and broader environmental impact