The impact of climate change on local discharge variability is investigated in the Kone River basin located in Central Vietnam. In this study, historical and predicted river discharge trends are discussed. The predicted discharge is simulated using the BTOPMC model based on the A1B scenario as a scientific basis for socioeconomic development and integrated water resource management in the Kone River basin, during the period 2011–2034. During the period 1979–2007, annual discharge in the Kone River basin trended upwards slightly. However, both maximum and minimum discharges declined. The results of the predicted discharge under the A1B scenario suggest that river flow will increase slightly in the Kone River basin in the future. Both annual and flood season discharges will tend to increase during the period 2011–2034. In contrast, discharge during the low flow season will tend to decrease over the same period. For the period 2011–2034, the discharge volume in the Kone River will increase by 3%, in comparison with the period 1980–1999. Water volume will decrease by about 18.6% during the flood season and increase by approximately 90.0% during the low flow season relative to the period 1980–1999.

Evaluating the dynamics of the Hau River estuary (Dinh An - Tranh De river mouth)

This research simulates and forecasts the area as well as the level of pollution dispersion of Muc Son Paper Factory’s wastewater to the downstream of Chu River under two scenarios: Scenario 1 - wastewater treatment system is broken; treatment efficiency is equal to 0; Scenario 2 - wastewater treatment system is working with its designed capacity. The applied results of the MIKE 11 model show that: the impacted area from the plant’s discharge is 0.2 km upstream and 2 km downstream of the confluence point. The simulation results under Scenario 1 show TSS, BOD5 and COD contents being 18.3–35.7 mg/L, 8.3–17.2 mg/L and 12.2–23.7 mg/L, respectively, negatively affect the water environment downstream of Chu river. The results are then compared with measured data to confirm the reliability of the model. This research is a scientific and practical basis for the Muc Son Paper factory to operate the wastewater treatment system and manage the water quality output to ensure environmental regulations.

Ly Son (Quang Ngai province) and Phu Quy (Binh Thuan province) are two island districts in Vietnam that have similar natural characteristics; both are facing the issues of sustainable economic development. This research applied Man-Kendall model to estimate the trend of some socioeconomic elements in these two island districts that have been collected during the period of 2002-2018. In general, socioeconomic factors showed a tendency to increase recently. Ly Son island district has faster growth rate than that of Phu Quy because Phu Quy is farther from the mainland, more difficult to access and this island district does not own distinct local products. However, with the current development speed, Ly Son is facing several consequences such as insufficient water sources to meet the water demand and security instability due to the increasing number of visitors to the island. This research also proposed that, in order to sustainably develop the two island districts, there should be a specific structure for economic development orientation among sectors based on phased schedule. More importantly, tourism development planning should take capacity into consideration. Fishing practices should pay attention to methods and fishing equipment. Infrastructure investment for environmental protection as well as advocacy program to minimize the use of plastic bags should be done on a regular basis.

Thành phố Cà Mau nằm phía Đông Bắc tỉnh Cà Mau có diện tích tự nhiên 249,29 km2, bằng 4,71% diện tích toàn tỉnh. Áp dụng các phương pháp chính là thống kê và so sánh, nghiên cứu đã tiến hành đánh giá tài nguyên nước mặt thành phố. Thành phố Cà Mau có nhiều tuyến sông lớn như sông Tắc Thủ, sông Gành Hào, kênh Xáng Cà Mau - Bạc Liêu và kênh Quản Lộ - Phụng Hiệp, thuận tiện để giao thông, phát triển kinh tế - xã hội. Chế độ thủy văn các sông trong thành phố Cà Mau khá phức tạp do chịu ảnh hưởng của chế độ bán nhật triều không đều biển Đông thông qua cửa Gành Hào. Qua kết quả quan trắc chất lượng nước trong 2 năm 2019 và 2021 có thể thấy nguồn nước mặt trong thành phố Cà Mau đã có dấu hiệu ô nhiễm dinh dưỡng, hữu cơ và vi sinh vật. Bài báo đã kiến nghị một số vấn đề cấp bách mà thành phố cần triển khai để bảo vệ tài nguyên và môi trường nước mặt thành phố Cà Mau.