Journal of Global Ecology and Environment

Changes in the Eurasian Otter (Lutra lutra) Population Including Assessment of Damage in the Last Decade: Is Their Protection Still Necessary?

Lucie Všetičková — Tue, 28 Nov 2023 00:00:00 +0000

Monitoring wildlife populations requires trustworthy assessment methods to get reliable data to be able to make reasonable management decisions. The Eurasian Otter (Lutra lutra) experienced a dramatic population decline throughout Central Europe during the twentieth century but is currently recovering in both distribution range and population size. Their numbers are regularly monitored by the relevant authorities, who issue an annual report on the occurrence of Eurasian Otters and the financial damage caused by them. These data for the last decade show that the abundance of Eurasian Otters in 2020 was 72% higher than in 2011 and that financial losses on fish farms has increased by 148% over the same period. In view of these facts, it is appropriate to discuss whether the Eurasian Otter is still an endangered species in Central Europe or whether the time has come for government regulation of their numbers, as has already happened with other initially protected animal, great cormorant (Phalacrocorax carbo).

Assessment of the Impacts of Climatic Factors and Economic Variables on Mangrove Ecosystem in Upenekang and Iwuochang, Southeastern Nigeria

Tue, 31 Oct 2023 00:00:00 +0000

The study assessed the impacts of climate change and economic variables on mangrove ecosystem in Upenekang and Iwuochang of Ibeno Local Government Area, Akwa Ibom State in a bid to understand the extent at which this ecological zone had contributed to the socio-economic well-being of the rural dwellers as well as its effects on the immediate environment. 200 copies of questionnaires were administered to respondents in the study area who were farmers, fishermen, fish traders, fuel wood dealers, boat builders and many others. Climatic variables like water temperature, salinity, rainfall, air pressure, pH, and tidal elevation were determined across ten sampling points. Questionnaires as well as semi-structured interviews were employed for the study in order to test for the hypotheses sets out for the study. The data generated from field study was further processed using chi-square to ascertain whether there is significant effect of rainfall on mangrove productivity using multiple regressions. The results indicated that the computed F value of 0.873 is greater than the significant F value of 0.151 and this indicates that there is a significant effect of rainfall and climate variability on mangrove productivity in the study area. The result produces Pearson Chi-Square value of 275.673^a, degree of freedom (df) of 24 and a P-value (2-sided) of 0.000 indicating that there is significant impact of mangrove on economic development in the study area.

Evaluating the Pollution Levels and Ecological Risks of Heavy Metals in Sediments of Apapa Port in Lagos, South-western Nigeria

Sat, 25 Nov 2023 00:00:00 +0000

The coastal sediments of Apapa Port in Lagos, Southwestern Nigeria were studied to determine the status of contamination due to the present of heavy metals and its effect on the ecosystem. The sediments samples were subjected to Particle Induce X-ray Emission (PIXE) technique analysis to determine heavy metals present in them. Ten (10) heavy metals were detected with which their concentrations ranged as Ti (2787.0 - 5672.9 mg/kg), Cr (95.4 - 285.9 mg/kg), Mn (124.8 - 526.7 mg/kg), Fe (20263.7 – 49953.7 mg/kg), Cu (8.0 – 13.4 mg/kg), Zn (280.1 – 1246.5 mg/kg), Rb (58.6 – 336.1 mg/kg), Sr (39.3 – 233.5 mg/kg), Zr (89.3 – 190.1 mg/kg), and Pb (13.3 – 31.1 mg/kg). The extent of contamination of the heavy metals was enumerated by comparing their concentrations with the USEPA guidelines, TEL and PEL. Different pollution indices such as enrichment factor (EF), geo-accumulation index (Igeo), contamination factor (CF), modified degree of contamination (mCd), pollution load index (PLI), and potential ecological risk index (PERI) were applied to estimate the level of toxicity imposed on the ecosystem by the detected heavy metals. These showed that the studied sediments were severely enriched with Zn at site 5 and moderately enriched with Cr and Rb at stations 5 and other respectively but the sum of all risk factors for those heavy metals is low. Statistical analysis such as the cluster analysis and Pearson’s correlation coefficient were also employed to determine the relationships of those heavy metals with respect to their origin. These revealed strong positive and negative correlations among the heavy metals and are cluster in terms of similarities as (1) Ti-Fe-Mn (2) Rb-Pb (3) Sr (4) Cu-Zn-Cr-Zr. This studied area requires proper monitoring to avert increase in ecological risk factor due to anthropogenic influences.