Clear-Cutting of Acacia Plantation in a Headwater Catchment of Vietnam: Environmental Impacts and Solutions for Sustainable Management

Abstract

To assess impacts of clear-cutting at a pure Acacia plantation on soil and water quality, a 7-year-old Acacia forest within the area of 2.5 ha in Hoa Binh province was selected to investigate at 2 stages: before and after clear-cutting. 03 standard plots (500 m2/plot) at 3 positions (downhill, mid-hill and top-hill) for determining forest characteristics, 30 sampling subplots (1 m2/plot) for monitoring forest covers and some soil properties. 15 of 30 subplots were used to measure infiltration; and 4 points along forest flow were chosen to take water sampling for assessing water quality. Main findings include: (1) Forest cover decreased within the removal of tree, reduction of understory vegetation cover, litter and biomass ranged from 10 to 20%; (2) Soil quality decreased by 8.35% dropped of porosity due to the rise of 8.57% in dry bulk density; (3) Soil nutrients: Organic matter, total Phosphorus and Nitrogen amount decreased at the proportion of 20.91%, 62.86% and 27.86% respectively after clear-cutting; (4) Total infiltration rate decreased after harvesting. The positions that had high infiltration rate before clear-cutting tended to infiltrate noticeably less (Downhill: reducing from 397.7 mm to 201.2 mm); (5) Soil erosion increased significantly after cutting and was remarkably higher in comparison with other research results due to the slope of researching area; (6) Most water quality indicators were at acceptable values, however, TSS and COD were 180-time and 5.6-time higher than water standard at B1 category (water for irrigation) according to QCVN 08:2015/BTNMT; (7) Some solutions suggested for sustainable management are (a) replacing production planted forest at researching site by protection forest or natural forest or (b) remaining commercial plantation forest but adjust management methods.

Soil Organic Carbon Stock Assessment for Volunteer Carbon Removal Benefit: Methodological Approach in Chestnut Orchard for Fruit Production

“…Regarding the soil sampling methodology, in the present investigation, the soil samples were collected from each identified pedogenic horizon. The B horizons were not observed in CO, likely due to the intense erosion processes that occurred after clear-cutting [119,120]. Despite this, it is important to mention that combining C evaluation with the identification of pedogenic soil horizons should be recommended.…”

The Acacia Plantation Boom in Thừa Thiên Huế Province, Central Vietnam: A Survey of Tree Farmers’ Shifting Livelihoods, Environmental Perceptions, and Occupational Perspectives

“…The effect of a dense tree cover to prevent (or mitigate against) soil erosion can be expected to be more immediately evident on acacia plots, and the observed response patterns reflect the fact that older and more densely growing tree stands are more effective than smaller and more frequently cut short-rotation tree stands (cf. Sun et al, 2018, Dung and Kim 2021, Podwojewski et al, 2008cf. also Pirard et al, 2017).…”

Entropy weight application for calculating groundwater quality index (EWQI) in groundwater quality zoning in Pleistocene aquifer in the Phu My town, Ba Ria – Vung Tau province

“…Các nghiên cứu này đã ứng dụng phương pháp WQI đánh giá chất lượng nước mặt, nước dưới đất dựa vào thông số đặc trưng chất lượng nước để tiến hành phân vùng, giám sát và quản lí nguồn nước. Ở Việt Nam, phương pháp chỉ số chất lượng nước cũng được sử dụng rộng rãi để đánh giá chất lượng nước mặt, nước dưới đất cho mục định nông nghiệp 11 . Tuy nhiên, trong phương pháp WQI, việc lựa chọn trọng số của từng thông số thường được đưa ra bởi ý kiến cá nhân của chuyên gia đánh giá dựa trên kinh nghiệm thực tế.…”