Application of multiple indices to the evaluation of trophic and ecological status in a tropical macrotidal estuary (Equatorial Margin, Brazil)

2022 ◽  
pp. 1-23
Author(s):  
Lisana F. Cavalcanti ◽  
Marco V. J. Cutrim ◽  
Cybelle C. S. Maciel ◽  
Ana Karoline D. dos S. Sá ◽  
Andrea C.G. Azevedo-Cutrim ◽  
...  
Author(s):  
Antanas DUMBRAUSKAS ◽  
Nijolė BASTIENĖ ◽  
Petras PUNYS

GIS-based approach to find the suitable sites for surface flow constructed wetlands was employed for the Lithuanian river basins with low ecological status. According to the nature of the analysed criteria the flowchart consists of two phases. Criteria used include hydrographical network, soil properties, terrain features, land use, etc. Some of them have strictly defined values (constraints), and other ranges within certain limits (factors). Limited criteria were analysed using rejection principle and influencing factors using proximity analysis and overlay methods. Selecting the potential sites using standard GIS analysis tools there was estimated about 3286 sites for possible wetlands with the mean area of inflow basin about 4 km2 in the basins of water bodies at risk.


2017 ◽  
Vol 11 (1) ◽  

With the exponential rise of human activities in the past decades, majority of studies conducted in Taal Volcano Protected Landscape (TVPL) are geared towards the conservation and preservation of Lake Taal’s remaining biodiversity. However, the current structure and assemblage of its terrestrial biotic communities remain relatively unstudied. In this study, we conducted biodiversity censuses in the four sites in TVPL to provide baseline information regarding the community structure of the selected study sites. Comparison of the plant diversity in Taal Volcano Crater Island and Romandan Falls within the forested areas of Mataas na Kahoy, Batangas reveal that both sites support remarkably different vegetation, with the former supporting a smaller floral diversity. The fairly small number of animal samples present difficulty in providing conclusive findings to the wildlife structure of the two study sites. However, the presence of 11 animal species exhibit valuable results in determining the ecological status of TVPL. It is deduced that several ecological barriers exist between the sites, which is attributed to their unique terrestrial biota.


2014 ◽  
Vol 13 (7) ◽  
pp. 1641-1656 ◽  
Author(s):  
Maria-Ema Faciu ◽  
Roxana Nechifor ◽  
Dan Dascalita ◽  
Camelia Ureche ◽  
Dorel Ureche ◽  
...  

Author(s):  
P. N. Vanyushin ◽  
A. V. Kuzin ◽  
А. А. Pavlov ◽  
А. V. Nefedov ◽  
N. А. Ivannikova

The article analyzes the current state of the irrigation and drainage systems of the Ryazan region. It is shown that the lack of technical operation of the drainage network led to its failure and failure to perform its functions. Irrigation, in spite of the fact that it gives stability in the years of droughts due to aging and the dismantling of machinery and equipment is not carried out. It is shown that for the reconstruction and / or modernization of irrigation and drainage systems it is necessary on the basis of inventory to determine the environmentally optimal and economically viable systems, their parts and structures that require rehabilitation, reconstruction and / or modernization. The decision to reconstruct may include not only the ameliorative system as a whole, but also some part of it, for example, a canal, pipeline or a separate hydraulic structure, taking into account the justification of economic feasibility. In dry periods, for the Meshcherskaya lowland and areas with peat soils, it is necessary to provide for land-reclamation systems for dual regulation of soil moisture, which reduces the possibility of peat ignition and the spread of fire. It should be borne in mind that the reconstruction of land-reclamation systems has its specific features, which include: socio-economic (increasing the productivity of agricultural land, obtaining additional income, creating modern infrastructure, increasing employment, living conditions, labor, etc.) ; ecological (creation of cultural landscapes, ensuring their ecological sustainability, prevention of land degradation processes, improvement of recreational conditions, elimination of waterlogging, flooding, salinization, erosion, etc.). Reclamation activities are carried out in compliance with the requirements of land, water, forestry legislation of the Russian Federation, as well as the legislation of the Russian Federation on the protection of the environment, on the subsurface, on the plant world and on the animal world.


2021 ◽  
Vol 13 (11) ◽  
pp. 6078
Author(s):  
Xiufen Li ◽  
Lining Song ◽  
Zunbo Xie ◽  
Tian Gao ◽  
Tingting Wang ◽  
...  

Quantitative assessment of ecological vulnerability is of great significance for ecological protection and restoration in ecologically vulnerable regions. Here, the ecological vulnerability of the northern sand prevention belt (NSPB) of China was assessed using an ecological pressure–sensibility–resilience model from 2000 to 2015. Results showed that the ecological vulnerability index (EVI) displayed low values in the eastern part and high values in the western part of the study region. The EVI ranged from 0.29 to 1.32 in 2000, with the mean value of 0.88, whereas it averaged 0.78 in 2015, ranging from 0.21 to 1.26. Decreasing EVI from 2000 to 2015 indicated that the ecological status has been improved. Moreover, the area proportion of moderately, heavily, and extremely ecological vulnerability levels occupied approximately 87% in both 2000 and 2015, indicating a high ecological vulnerability level. Furthermore, the change in area proportion of different ecological vulnerability levels were associated with the change in the spatial distribution of vegetation coverage, indicating that eco-environmental protection projects were indeed effective. These findings indicated that differential strategies in different restoration zones should be adopted, especially in the western parts of the study region, and eco-environmental protection projects should be reinforced to improve the ecological restoration.


Water ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 433
Author(s):  
Laima Česonienė ◽  
Midona Dapkienė ◽  
Petras Punys

Hydropower plants produce renewable and sustainable energy but affect the river’s physico-chemical characteristics and change the abundance and composition of the aquatic organisms. The impact of large HPPs on the ecological conditions of surface water bodies have been extensively studied, but less attention has been paid to environmental impact studies of small hydropower plants (SHPs). The impact of hydropeaking on both the river flow regime and ecosystems has been well-studied for peaking mode plants, mainly medium to large-sized ones. However, for small hydroelectric power plants, and especially for those in lowland rivers, the available information on water quality, benthic macroinvertebrates communities and fish abundance, and biomass is not sufficient. Ten small hydropower plants were selected, and the ecological status of water bodies was assessed in different parts of Lithuania. The studies were performed at the riverbed upstream from the SHPs, where the hydrological regime has not changed, and downstream from the SHPs. It was found that the small hydropower plants do not affect the physico-chemical values of the water quality indicators. This study demonstrated that the total number of benthic macroinvertebrates taxa (TS) is influenced by the concentration of nitrogen and suspended solids, the water flow, the river area, and the current speed; the number of EPT (Ephemeroptera (mayflies), Plecoptera (stoneflies), and Trichoptera (caddisflies)) taxa is influenced by the concentration of nitrogen and suspended solids. The studied indicators do not have a significant impact on biomass. The SHPs affect the fish abundance and biomass. The Lithuanian fish index (LFI) is influenced by the average depth and area of the river. Some SHPs operating in lowland areas may yield somewhat significant hydrograph ramping but more detailed investigation is needed to support the significance of this impact on the biological indices.


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