Search Results (3)

Lentic ecosystems are highly vulnerable to anthropogenic disturbances, which can lead to ecological imbalances with the loss of native biodiversity. This research evaluated the impact of anthropogenic activities on water quality and the trophic status of the Pacucha Lagoon, Andahuaylas, Apurimac. Seasonal sampling was conducted at six strategic points on the surface and bottom of the lake, following standardized protocols, during both the dry and rainy seasons. Physical and chemical parameters, metal ions, chlorophyll-a, and trophic status were determined using the Carlson indices, and water quality was assessed through the WQI-PE. The quantification of anthropogenic impacts was performed using the Leopold matrix. Statistical analysis included descriptive methods, ANOVA, Pearson correlation, and PCA at 5% significance. The results classify the lake as having “Regular” water quality according to WQI-PE. Physical and chemical parameters remain within the Environmental Quality Standards (ECA-Peru), while heavy metal ions exceed the limits in both seasons. The system exhibits mesotrophic conditions that tend to become eutrophic during the rainy season, suggesting a favorable nutrient balance for biological productivity. Activities with the most significant adverse impacts include agricultural practices that involve the intensive use of agrochemicals, morphological alterations to the surrounding area, and unregulated aquaculture. The lack of effective regulatory mechanisms and a lack of commitment to conservation suggest a high risk of irreversible degradation of the Pacucha Lagoon ecosystem. Full article

In order to validate the applicability of pXRF for rapid in situ detection of heavy metals in urban soils and to accurately obtain an assessment of soil quality in Changchun, a city in northeast China, 164 soil samples from within the main urban area of Changchun were collected for pXRF analysis. The main stable elements Si and Ti were used to establish a matrix effect correction model, and the values of Cr (64.2 mg⋅kg⁻¹), Cu (43.8 mg⋅kg⁻¹), Zn (96.2 mg⋅kg⁻¹), As (20.9 mg⋅kg⁻¹), and Pb (57.4 mg⋅kg⁻¹) were predicted. The empirical findings indicate that the quality of soil data from the pXRF was improved to different degrees under the correction model, and it became a relatively reliable dataset; the order of improvement was Cu > Pb > Cr > Zn > As. A comprehensive assessment indicated that Changchun City is primarily contaminated by the heavy metals As, Pb, and Cu, with the main sources being automobile manufacturing and pharmaceutical chemical production. These findings align with previous studies and have produced favorable outcomes in practical applications. This rapid, non-destructive and economical detection method is very applicable and economical for the sustainable monitoring and control of heavy metals in large cities. This study provides a basis for rapid large-scale prediction of urban soil safety and protection of local human health. Full article

Currently, construction projects have a significant share in environmental pollution. Usually, the employers and managers of construction projects pay attention to the project implementation with the shortest duration and the lowest cost, whereas less attention is paid to the environmental effects of the implementation of projects. Sustainable development requires the planning and implementation of construction projects, taking environmental impacts, along with other factors, into account. Few studies have investigated the balancing time, cost, and environmental effects. Although the selection of an execution method for the project activity requires the use of decision-making methods, these methods have not been used in the project scheduling problems. This study seeks to simultaneously minimize the project time, cost, and environmental impacts. The purpose of this study is to evaluate the environmental impact of project activities in three physical, biological, and social aspects throughout the construction projects, and to attempt to minimize them as measurable values. In this paper, the environmental effects of an urban water supply construction project as a real case study are assessed in different activity execution modes by the Leopold matrix and the best execution mode of each project activity is selected using the CoCoSo (combined compromise solution) multi-criteria decision-making method, considering the time–cost-environmental impact trade-off. The CoCoSo method is employed because of its high flexibility compared to other multi-criteria decision-making methods. The results of this study will direct managers and stakeholders of construction projects to pay more attention to the environmental effects of construction project activities, together with the other conventional project goals and objectives, such as the time and cost. Full article