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Tom 41 (2022): Zeszyt 4 (December 2022)

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Tom 40 (2021): Zeszyt 4 (December 2021)

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Tom 40 (2021): Zeszyt 2 (June 2021)

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Tom 39 (2020): Zeszyt 4 (December 2020)

Tom 39 (2020): Zeszyt 3 (September 2020)

Tom 39 (2020): Zeszyt 2 (June 2020)

Tom 39 (2020): Zeszyt 1 (March 2020)

Tom 38 (2019): Zeszyt 4 (December 2019)

Tom 38 (2019): Zeszyt 3 (September 2019)

Tom 38 (2019): Zeszyt 2 (June 2019)

Tom 38 (2019): Zeszyt 1 (March 2019)

Tom 37 (2018): Zeszyt 4 (December 2018)

Tom 37 (2018): Zeszyt 3 (September 2018)

Tom 37 (2018): Zeszyt 2 (June 2018)

Tom 37 (2018): Zeszyt 1 (March 2018)

Tom 36 (2017): Zeszyt 4 (December 2017)

Tom 36 (2017): Zeszyt 3 (September 2017)

Tom 36 (2017): Zeszyt 2 (June 2017)

Tom 36 (2017): Zeszyt 1 (March 2017)

Tom 35 (2016): Zeszyt 4 (December 2016)

Tom 35 (2016): Zeszyt 3 (September 2016)

Tom 35 (2016): Zeszyt 2 (June 2016)

Tom 35 (2016): Zeszyt 1 (March 2016)

Tom 34 (2015): Zeszyt 4 (December 2015)

Tom 34 (2015): Zeszyt 3 (September 2015)

Tom 34 (2015): Zeszyt 2 (June 2015)

Tom 34 (2015): Zeszyt 1 (March 2015)

Tom 33 (2014): Zeszyt 4 (December 2014)

Tom 33 (2014): Zeszyt 3 (September 2014)

Tom 33 (2014): Zeszyt 2 (June 2014)

Tom 33 (2014): Zeszyt 1 (March 2014)

Tom 32 (2013): Zeszyt 4 (December 2013)

Tom 32 (2013): Zeszyt 3 (September 2013)

Tom 32 (2013): Zeszyt 2 (June 2013)

Tom 32 (2013): Zeszyt 1 (March 2013)

Informacje o czasopiśmie
Format
Czasopismo
eISSN
1337-947X
Pierwsze wydanie
24 Aug 2013
Częstotliwość wydawania
4 razy w roku
Języki
Angielski

Wyszukiwanie

Tom 41 (2022): Zeszyt 3 (September 2022)

Informacje o czasopiśmie
Format
Czasopismo
eISSN
1337-947X
Pierwsze wydanie
24 Aug 2013
Częstotliwość wydawania
4 razy w roku
Języki
Angielski

Wyszukiwanie

11 Artykułów
Otwarty dostęp

Assesment of heavy metals concentration in initial soils of post-mining landscapes in Kryvyi Rih District (Ukraine)

Data publikacji: 17 Oct 2022
Zakres stron: 201 - 211

Abstrakt

Abstract

Assessment of heavy metals content in the initial soils of the post-mining landscapes plays an important role in pollution control, ecological protection, and safe-guarding human health. In this study, the site-specific pedogeochemical background contents of several metals in soils in Kryvyi Rih Iron Ore Mining & Metallurgical District (central part of Ukraine) were determined. The metal concentrations in the soils of Petrovsky waste rock dump were also quantified and were also assessed using indices of pollution. The field sampling was carried out at a depth of 0-10 cm in five plots in dump area and in one plot in control site. The 43 soil samples were collected. The results showed that local background concentrations of heavy metals in soils of studied area decreased in the following order (mg×kg−1): Fe (42 510) > Mn (761.7) > Cr (94.48) > Zn (90.51) > > As (31.85) > Cu (28.10) > Pb (18.73) > Co (16.21) > Sn (4.64) > Mo (0.28) > Cd (0.16). In the initial soils of devastated lands at Petrovsky waste rock dumps the predominance of increased Cd, Co, Fe, Mm, Mo and Sn content and the predominance of decreased As, Cr and Pb content were observed. Based on the mean values of the individual indices of pollution (Pollution index, Geoaccumulation index, Enrichment factor, Contamination factor) can be assumed that in these soils As, Cd, Fe, Mo, Pb and Sn are mostly coming from industrial activities. Co, Cr, Cu, Mn and Zn are mostly related to their natural occurrence in devastated lands. The values of integrated indices of pollution (Nemerow pollution index, Pollution load index, Degree of contaminated, Modified degree of contamination) indicated that the initial soils of post-mining landscapes can be evaluated as no polluted – and extremely heavy polluted.

Słowa kluczowe

  • landscape ecology
  • environmental chemistry
  • devastated lands
  • indices of pollution
  • iron ore mining area
  • waste rock dumps
Otwarty dostęp

Post-fire dynamics of the main biogenic nutrients of the Pinus pinaster forest soil of Jijel, Northeastern Algeria

Data publikacji: 17 Oct 2022
Zakres stron: 212 - 218

Abstrakt

Abstract

Forest fires are part of the natural dynamics of Mediterranean forest ecosystems. In the Mediterranean regions, the ecosystems are shaped by this disturbance that they have been subjected to for a long time. This work aimed to study the effect of fire on the superficial soil of the Pinus pinaster forest of Jijel, Northeastern Algeria. Soil samples were taken at a depth of 0–5 cm at different dates over a period of 24 months, in a diachronic mode. The following parameters have been tested: total carbon (C), total nitrogen (N), pH, cations exchange capacity (C.E.C.) and main exchangeable bases: calcium (Ca2+), magnesium (Mg2+), sodium (Na+) and potassium (K+). The results of the study showed a significant soil enrichment during the first few months after the fire; this temporary high fertility decreases with time due to ecosystem recovery, which could be interpreted as a return to the pre-fire state.

Słowa kluczowe

  • biogenic elements
  • forest
  • soil
  • wildfires
Otwarty dostęp

Characterization and diversity of macroin-vertebrates in groundwater in the region of Souk-Ahras (North-East of Algeria)

Data publikacji: 17 Oct 2022
Zakres stron: 219 - 227

Abstrakt

Abstract

A preliminary inventory of macroinvertebrate communities and a regular physicochemical analysis of groundwater were carried out in the Souk Ahras region (north-eastern Algeria). It aims to study and analyze the structure and distribution of underground aquatic species, thus determining the relationship that may exist between the quality of water in wells and springs with the diversity of aquatic fauna present in the habitats. Through 2018, 14 stations (10 wells and 4 springs) were monitored on a monthly basis, while water and aquatic fauna samples were taken. A principal component analysis (PCA) of the physicochemical quality parameters was carried out from the average values of each parameter. It has been observed that the waters are highly mineralized, due to the high values of total hardness, salinity, and sulfate levels in certain stations. The sources of contamination are mainly due to the raw wastewater circulating in the small canals. Also “seguias” are used either to evacuate wastewater or for irrigation, which seeps down to the water table. The collected aquatic fauna in all the 14 stations is diversified and contains 29 families which correspond to 4 taxa.

Słowa kluczowe

  • macroinvertebrate communities
  • ground water
  • Algeria
Otwarty dostęp

Ecodendrometric study of stone pine (Pinus pinea L.) in the region of Mostaganem (western Algeria)

Data publikacji: 17 Oct 2022
Zakres stron: 228 - 235

Abstrakt

Abstract

The evaluation and monitoring of forest species provide a fundamental source of information for the implementation of effective and adapted conservation strategies for these species. The present study aims to determine the ecodendrometric characterisation of even-aged stone pine stands in the region of Mostaganem (western Algeria). Seventy-two temporary plots (1,151 trees) of circular shape with a surface area of (4–6 a) were installed according to age and density in stands that were as regular as possible. These plots were subjected to a complete dendrometric inventory (total height, crown diameter, circumference at 1.3 m, age, etc.) and an ecological description (soil depth, altitude, aspect and slope). It was found that this species is characterised by a regular structure forming young populations. Relationships between parameters such as mean total height/mean circumference, mean crown diameter/diameter at 1.3 m and basal area/mean crown diameter were very positive and significant. The ecodendrometric data was processed by a multivariate principal component analysis, which revealed the effect of altitude, especially soil depth, on stone pine production.

Słowa kluczowe

  • stone pine
  • dendrometric inventory
  • ecological factors
  • production
  • western Algeria
Otwarty dostęp

Predicting suitable habitats of the major forest trees in the Saïda region (Algeria): A reliable reforestation tool

Data publikacji: 17 Oct 2022
Zakres stron: 236 - 246

Abstrakt

Abstract

Modeling potential habitat for plant species is an appropriate approach to maintain biodiversity, developing proper reforestation campaigns, and rehabilitating ecosystems. In this study, we investigated the potential distributions of four forest species, namely, Quercus faginea Lam.; Q. ilex L.; Tetraclinis articulata (Vahl) Mast.; and Pistacia atlantica Desf. In the north-western Algeria at Saïda region. The MAXENT method was used to model the habitats of these species using topographic data as predictive variables at a resolution of 100 m. Moreover, the model evaluation process was achieved using the area under the operating characteristic curve of the receiver (AUC) and Jackknife test.

The generated models were found to be accurate. AUC results are ranging between 0.98 and 0.91 for the training set and 0.87 and 0.97 for the testing set. The results of the distribution probability of this study provide a useful tool for the local decision-makers of reforestation campaigns.

Słowa kluczowe

  • Spatial Distribution Model
  • MAXENT
  • reforestation
  • Saïda
  • topographic variables
Otwarty dostęp

Distribution of breeding waterbirds in relation to wetland characteristics in the Oued Righ valley in the Algerian Sahara

Data publikacji: 17 Oct 2022
Zakres stron: 247 - 253

Abstrakt

Abstract

In the framework of this study 14 breeding species were identified in the wetland complex of the Oued Righ valley in the Algerian Sahara. Six species of breeding Anatidae were reported, two of which are classified as vulnerable and threatened, namely, the ferruginous duck Aythya nyroca and the marbled teal Marmaronetta angustirostris. For shorebirds, we noted reproduction of the pied avocet Recurvirostra avosetta, the black-winged stilt Himantopus Himantopus, and the Kentish plover Charadrius alexandrinus in most of the wetlands studied. We report for the first time nesting of the slender-billed gull Chroicocephalus genei at Chott Merouane with 72 pairs recorded during the breeding season 2018. This colony was associated with the larger colony of greater flamingo Phoenicopterus roseus composed of 640 pairs. Principal component analysis (PCA), gathering 69.74% of the information, showed a significant correlation between the distribution of different bird species and the main environmental factors, that is, vegetation, water surface area, water depth, and salinity, and a strong correlation between the species of Annatidae and Rallidae, which are associated with less-saline environments rich in vegetation and deep water, with the exception of shelducks, which prefer large surface areas with less-dense vegetation and more holomorphic water. For the shorebirds such as R. avosetta and H. himantopus, there was a clear preference for large wetlands with shallow water and relatively high salinity. A remarkable correlation was also noted for P. roseus, where a strong distribution of breeding populations was observed in areas with the highest salinity levels and a vast surface area.

Słowa kluczowe

  • wetlands
  • waterbirds
  • Anatidae
  • shorebirds
  • Sahara
Otwarty dostęp

Reproductive phenology of the spider Micrommata ligurina (C.L. Koch, 1845) (Araneae; Sparassidae) across an elevational gradient in Northeast Algeria

Data publikacji: 17 Oct 2022
Zakres stron: 254 - 261

Abstrakt

Abstract

Decreased ambient temperature and shorter reproductive seasons are the two main obstacles that ectotherms face at higher elevations. Studies have shown that some life history traits such as phenological windows of activity, duration, and fitness components vary as elevation increases. However, studies on the elevational gradient at the southern range limit of species are lacking. In this study, we aim at assessing some aspects of the life history of a spider species, the sprassid Micrommata ligurina (C.L. Koch, 1845), across an elevational gradient from 30 to 1030 m in Northeast Algeria. There was strong evidence of an elevational shift in the phenology of reproduction with a delay rate of 2.2 days per 100 m of elevation, and the three quantiles of the phenology (10, 50, and 90%) shifted with the same magnitude across elevation. In all sites from low to high elevation, the species showed a decrease in number of individuals. The mean number of eggs was 200 ± 35 eggs, and the mean number of hatching eggs was 110.9 ± 23.5 eggs. The clutch size at high elevation sites was higher than that of low-elevation sites, but in contrast, the hatching success was higher at lower elevation sites. Overall, the species exhibited clear elevational clines in life history traits and abundance, suggesting a high potential of plasticity. This work constitutes the first study carried out on spider species ecology in the region.

Słowa kluczowe

  • life history
  • hatching success
  • elevation gradients
  • North Africa
Otwarty dostęp

Farmers’ Preference and Willingness to Pay for Climate-Smart Rice Varieties in Uzo-Uwani Local Government Area of Enugu State, Nigeria

Data publikacji: 17 Oct 2022
Zakres stron: 262 - 271

Abstrakt

Abstract

This paper examined farmers’ preference and willingness to pay (WTP) for climate-smart rice varieties in Uzo-Uwani Local Government Area of Enugu State, Nigeria. A total of 80 respondents were purposely selected from 5 major rice growing communities in the study area. Questionnaire was the main tool for data collection. Also, data on climate elements (such as temperature and rainfall volume) for a period of 35 years (1986–2020) were obtained from the Nigerian Meteorological Agency (NIMET). Multinomial logit model, ordinary least square (OLS) regression model, descriptive statistics and trend analysis were employed for data analysis. The results show that FARO 44 was preferred by 95% of the farmers for grain size, 100% of farmers preferred it for days to maturity, 76.2% preferred it for strength of grain to withstand breakage during processing, 98.75% preferred it for potential yield (tons) and plant height (cm) and 87.5% preferred it for its ecological adaptation. Farmers’ preference and willingness to pay for climate-smart rice varieties were influenced by attributes of these varieties and knowledge of such technologies, primary occupation, farm size, extension visits and access to media information and farm size. This study recommends that government should provide extension agents with the adequate resources to enable them carry out their duties more effectively.

Słowa kluczowe

  • climate change
  • climate-smart rice varieties
  • preference
  • willingness to pay
  • multinomial logit regression
  • ordinary least square regression
  • trend analysis
Otwarty dostęp

Assessment in treatment efficiency of a small-scale municipal wastewater treatment plant with activated sludge

Data publikacji: 17 Oct 2022
Zakres stron: 272 - 282

Abstrakt

Abstract

In this paper, the treatment efficiency of a small-scale wastewater treatment plant (WWTP) with activated sludge was analysed in order to examine the impact of variations in the composition of incoming raw municipal wastewater. The characteristics of the wastewater were analysed with respect to COD, BOD5 and TSS values and loading during the two years, 2018 and 2019. The mixed liquid suspended solid (MLSS), sludge volume index (SVI), food to microorganism ratio (F/M), sludge age and hydraulic retention time (HRT) were used for evaluation of the performance of WWTP. Removal percentage is in the order of TSS > BOD5 > COD during 2018, while in 2019 is in the order BOD5 > TSS > COD. However, better values of removal efficiency for COD, BOD and TSS are obtained in 2019, which is connected to lower oscillation values of MLSS and SVI index. Biodegradability ratio of raw and treated wastewater, plant reliability factor (RF) and equivalent number of inhabitant (ENI) were determined. In addition, the economic cost of small-scale wastewater treatment plant (WWTP) with activated sludge was evaluated and discussed.

Słowa kluczowe

  • physicochemical indicators
  • wastewater treatment plant
  • activated sludge
  • sludge volume index
  • plant reliability factor
Otwarty dostęp

Climate change adaptation strategies by rice processors in Ebonyi State, Nigeria

Data publikacji: 17 Oct 2022
Zakres stron: 283 - 290

Abstrakt

Abstract

The paper examined adaptation strategies used by rice processors in Ebonyi State to manage climate risks. The paper used random sampling technique to select respondents and questionnaire was used to collect data from the respondents. Cross-sectional data collected from 98 rice processors were analysed using descriptive statistics and multivariate probit regression model. The results indicated that majority of the rice processors perceived prolonged dry season and increased rainfall intensity as the main climate risks in the state. Livelihood diversification, storing of paddy, and reliance on climate information were the major adaptation strategies used by the rice processors to manage the climate risks. The main determinants of climate change adaptation strategies of rice processors were education, membership of cooperative societies, income, training on rice processing and climate risk management, experience of climate hazards, and ownership of assets. The processors faced various barriers to adoption which are mainly related to capital needs, competition from foreign brands, access to basic infrastructure and roads and information, high cost of labour. It is recommended that government support be given to the rice producing communities in terms of basic infrastructure and policies to protect the industry. Also, regular workshops/trainings should be held to train processors on best climate risk management practices and encourage registration of processor cooperatives/relevant associations.

Słowa kluczowe

  • rice processing
  • adaptation
  • cross-sectional data
  • multivariate probit regression
  • barriers
  • Nigeria
Otwarty dostęp

Definition of hot-spots to reduce the nitrogen losses from agricultural land to groundwater in Slovakia

Data publikacji: 17 Oct 2022
Zakres stron: 291 - 300

Abstrakt

Abstract

Agriculture is a significant contributor to nitrate pollution of groundwater which in many cases serves as a source of drinking water. Therefore, targeted reduction of nitrogen leaching losses is fully justified to address this issue. The aim of the study was to define the areas of utilized agricultural land (UAL) in Slovakia, where a nitrogen surplus needs to be reduced. Using the average values of leachable nitrogen in the period 2015-2018 and the long-term amount of percolated water, the nitrate concentration in leachate was calculated. To ensure that agricultural activities will contribute to the gradual reduction of nitrate concentration in groundwater, the nitrate concentration in leachate of 40 mg L-1 was chosen as the target value. This concentration was exceeded at 11.7% of the UAL area. The average indicative amount of nitrogen in industrial fertilizers that needs to be reduced to achieve a stricter nitrate concentration in the leachate in these hot-spots is 16 kg ha-1 with the proviso that in two districts this value exceeds 30 kg ha-1.

Słowa kluczowe

  • Nitrates Directive
  • groundwater pollution
  • vulnerable zones
  • nitrogen surplus
  • nitrate concentration
  • leachate
11 Artykułów
Otwarty dostęp

Assesment of heavy metals concentration in initial soils of post-mining landscapes in Kryvyi Rih District (Ukraine)

Data publikacji: 17 Oct 2022
Zakres stron: 201 - 211

Abstrakt

Abstract

Assessment of heavy metals content in the initial soils of the post-mining landscapes plays an important role in pollution control, ecological protection, and safe-guarding human health. In this study, the site-specific pedogeochemical background contents of several metals in soils in Kryvyi Rih Iron Ore Mining & Metallurgical District (central part of Ukraine) were determined. The metal concentrations in the soils of Petrovsky waste rock dump were also quantified and were also assessed using indices of pollution. The field sampling was carried out at a depth of 0-10 cm in five plots in dump area and in one plot in control site. The 43 soil samples were collected. The results showed that local background concentrations of heavy metals in soils of studied area decreased in the following order (mg×kg−1): Fe (42 510) > Mn (761.7) > Cr (94.48) > Zn (90.51) > > As (31.85) > Cu (28.10) > Pb (18.73) > Co (16.21) > Sn (4.64) > Mo (0.28) > Cd (0.16). In the initial soils of devastated lands at Petrovsky waste rock dumps the predominance of increased Cd, Co, Fe, Mm, Mo and Sn content and the predominance of decreased As, Cr and Pb content were observed. Based on the mean values of the individual indices of pollution (Pollution index, Geoaccumulation index, Enrichment factor, Contamination factor) can be assumed that in these soils As, Cd, Fe, Mo, Pb and Sn are mostly coming from industrial activities. Co, Cr, Cu, Mn and Zn are mostly related to their natural occurrence in devastated lands. The values of integrated indices of pollution (Nemerow pollution index, Pollution load index, Degree of contaminated, Modified degree of contamination) indicated that the initial soils of post-mining landscapes can be evaluated as no polluted – and extremely heavy polluted.

Słowa kluczowe

  • landscape ecology
  • environmental chemistry
  • devastated lands
  • indices of pollution
  • iron ore mining area
  • waste rock dumps
Otwarty dostęp

Post-fire dynamics of the main biogenic nutrients of the Pinus pinaster forest soil of Jijel, Northeastern Algeria

Data publikacji: 17 Oct 2022
Zakres stron: 212 - 218

Abstrakt

Abstract

Forest fires are part of the natural dynamics of Mediterranean forest ecosystems. In the Mediterranean regions, the ecosystems are shaped by this disturbance that they have been subjected to for a long time. This work aimed to study the effect of fire on the superficial soil of the Pinus pinaster forest of Jijel, Northeastern Algeria. Soil samples were taken at a depth of 0–5 cm at different dates over a period of 24 months, in a diachronic mode. The following parameters have been tested: total carbon (C), total nitrogen (N), pH, cations exchange capacity (C.E.C.) and main exchangeable bases: calcium (Ca2+), magnesium (Mg2+), sodium (Na+) and potassium (K+). The results of the study showed a significant soil enrichment during the first few months after the fire; this temporary high fertility decreases with time due to ecosystem recovery, which could be interpreted as a return to the pre-fire state.

Słowa kluczowe

  • biogenic elements
  • forest
  • soil
  • wildfires
Otwarty dostęp

Characterization and diversity of macroin-vertebrates in groundwater in the region of Souk-Ahras (North-East of Algeria)

Data publikacji: 17 Oct 2022
Zakres stron: 219 - 227

Abstrakt

Abstract

A preliminary inventory of macroinvertebrate communities and a regular physicochemical analysis of groundwater were carried out in the Souk Ahras region (north-eastern Algeria). It aims to study and analyze the structure and distribution of underground aquatic species, thus determining the relationship that may exist between the quality of water in wells and springs with the diversity of aquatic fauna present in the habitats. Through 2018, 14 stations (10 wells and 4 springs) were monitored on a monthly basis, while water and aquatic fauna samples were taken. A principal component analysis (PCA) of the physicochemical quality parameters was carried out from the average values of each parameter. It has been observed that the waters are highly mineralized, due to the high values of total hardness, salinity, and sulfate levels in certain stations. The sources of contamination are mainly due to the raw wastewater circulating in the small canals. Also “seguias” are used either to evacuate wastewater or for irrigation, which seeps down to the water table. The collected aquatic fauna in all the 14 stations is diversified and contains 29 families which correspond to 4 taxa.

Słowa kluczowe

  • macroinvertebrate communities
  • ground water
  • Algeria
Otwarty dostęp

Ecodendrometric study of stone pine (Pinus pinea L.) in the region of Mostaganem (western Algeria)

Data publikacji: 17 Oct 2022
Zakres stron: 228 - 235

Abstrakt

Abstract

The evaluation and monitoring of forest species provide a fundamental source of information for the implementation of effective and adapted conservation strategies for these species. The present study aims to determine the ecodendrometric characterisation of even-aged stone pine stands in the region of Mostaganem (western Algeria). Seventy-two temporary plots (1,151 trees) of circular shape with a surface area of (4–6 a) were installed according to age and density in stands that were as regular as possible. These plots were subjected to a complete dendrometric inventory (total height, crown diameter, circumference at 1.3 m, age, etc.) and an ecological description (soil depth, altitude, aspect and slope). It was found that this species is characterised by a regular structure forming young populations. Relationships between parameters such as mean total height/mean circumference, mean crown diameter/diameter at 1.3 m and basal area/mean crown diameter were very positive and significant. The ecodendrometric data was processed by a multivariate principal component analysis, which revealed the effect of altitude, especially soil depth, on stone pine production.

Słowa kluczowe

  • stone pine
  • dendrometric inventory
  • ecological factors
  • production
  • western Algeria
Otwarty dostęp

Predicting suitable habitats of the major forest trees in the Saïda region (Algeria): A reliable reforestation tool

Data publikacji: 17 Oct 2022
Zakres stron: 236 - 246

Abstrakt

Abstract

Modeling potential habitat for plant species is an appropriate approach to maintain biodiversity, developing proper reforestation campaigns, and rehabilitating ecosystems. In this study, we investigated the potential distributions of four forest species, namely, Quercus faginea Lam.; Q. ilex L.; Tetraclinis articulata (Vahl) Mast.; and Pistacia atlantica Desf. In the north-western Algeria at Saïda region. The MAXENT method was used to model the habitats of these species using topographic data as predictive variables at a resolution of 100 m. Moreover, the model evaluation process was achieved using the area under the operating characteristic curve of the receiver (AUC) and Jackknife test.

The generated models were found to be accurate. AUC results are ranging between 0.98 and 0.91 for the training set and 0.87 and 0.97 for the testing set. The results of the distribution probability of this study provide a useful tool for the local decision-makers of reforestation campaigns.

Słowa kluczowe

  • Spatial Distribution Model
  • MAXENT
  • reforestation
  • Saïda
  • topographic variables
Otwarty dostęp

Distribution of breeding waterbirds in relation to wetland characteristics in the Oued Righ valley in the Algerian Sahara

Data publikacji: 17 Oct 2022
Zakres stron: 247 - 253

Abstrakt

Abstract

In the framework of this study 14 breeding species were identified in the wetland complex of the Oued Righ valley in the Algerian Sahara. Six species of breeding Anatidae were reported, two of which are classified as vulnerable and threatened, namely, the ferruginous duck Aythya nyroca and the marbled teal Marmaronetta angustirostris. For shorebirds, we noted reproduction of the pied avocet Recurvirostra avosetta, the black-winged stilt Himantopus Himantopus, and the Kentish plover Charadrius alexandrinus in most of the wetlands studied. We report for the first time nesting of the slender-billed gull Chroicocephalus genei at Chott Merouane with 72 pairs recorded during the breeding season 2018. This colony was associated with the larger colony of greater flamingo Phoenicopterus roseus composed of 640 pairs. Principal component analysis (PCA), gathering 69.74% of the information, showed a significant correlation between the distribution of different bird species and the main environmental factors, that is, vegetation, water surface area, water depth, and salinity, and a strong correlation between the species of Annatidae and Rallidae, which are associated with less-saline environments rich in vegetation and deep water, with the exception of shelducks, which prefer large surface areas with less-dense vegetation and more holomorphic water. For the shorebirds such as R. avosetta and H. himantopus, there was a clear preference for large wetlands with shallow water and relatively high salinity. A remarkable correlation was also noted for P. roseus, where a strong distribution of breeding populations was observed in areas with the highest salinity levels and a vast surface area.

Słowa kluczowe

  • wetlands
  • waterbirds
  • Anatidae
  • shorebirds
  • Sahara
Otwarty dostęp

Reproductive phenology of the spider Micrommata ligurina (C.L. Koch, 1845) (Araneae; Sparassidae) across an elevational gradient in Northeast Algeria

Data publikacji: 17 Oct 2022
Zakres stron: 254 - 261

Abstrakt

Abstract

Decreased ambient temperature and shorter reproductive seasons are the two main obstacles that ectotherms face at higher elevations. Studies have shown that some life history traits such as phenological windows of activity, duration, and fitness components vary as elevation increases. However, studies on the elevational gradient at the southern range limit of species are lacking. In this study, we aim at assessing some aspects of the life history of a spider species, the sprassid Micrommata ligurina (C.L. Koch, 1845), across an elevational gradient from 30 to 1030 m in Northeast Algeria. There was strong evidence of an elevational shift in the phenology of reproduction with a delay rate of 2.2 days per 100 m of elevation, and the three quantiles of the phenology (10, 50, and 90%) shifted with the same magnitude across elevation. In all sites from low to high elevation, the species showed a decrease in number of individuals. The mean number of eggs was 200 ± 35 eggs, and the mean number of hatching eggs was 110.9 ± 23.5 eggs. The clutch size at high elevation sites was higher than that of low-elevation sites, but in contrast, the hatching success was higher at lower elevation sites. Overall, the species exhibited clear elevational clines in life history traits and abundance, suggesting a high potential of plasticity. This work constitutes the first study carried out on spider species ecology in the region.

Słowa kluczowe

  • life history
  • hatching success
  • elevation gradients
  • North Africa
Otwarty dostęp

Farmers’ Preference and Willingness to Pay for Climate-Smart Rice Varieties in Uzo-Uwani Local Government Area of Enugu State, Nigeria

Data publikacji: 17 Oct 2022
Zakres stron: 262 - 271

Abstrakt

Abstract

This paper examined farmers’ preference and willingness to pay (WTP) for climate-smart rice varieties in Uzo-Uwani Local Government Area of Enugu State, Nigeria. A total of 80 respondents were purposely selected from 5 major rice growing communities in the study area. Questionnaire was the main tool for data collection. Also, data on climate elements (such as temperature and rainfall volume) for a period of 35 years (1986–2020) were obtained from the Nigerian Meteorological Agency (NIMET). Multinomial logit model, ordinary least square (OLS) regression model, descriptive statistics and trend analysis were employed for data analysis. The results show that FARO 44 was preferred by 95% of the farmers for grain size, 100% of farmers preferred it for days to maturity, 76.2% preferred it for strength of grain to withstand breakage during processing, 98.75% preferred it for potential yield (tons) and plant height (cm) and 87.5% preferred it for its ecological adaptation. Farmers’ preference and willingness to pay for climate-smart rice varieties were influenced by attributes of these varieties and knowledge of such technologies, primary occupation, farm size, extension visits and access to media information and farm size. This study recommends that government should provide extension agents with the adequate resources to enable them carry out their duties more effectively.

Słowa kluczowe

  • climate change
  • climate-smart rice varieties
  • preference
  • willingness to pay
  • multinomial logit regression
  • ordinary least square regression
  • trend analysis
Otwarty dostęp

Assessment in treatment efficiency of a small-scale municipal wastewater treatment plant with activated sludge

Data publikacji: 17 Oct 2022
Zakres stron: 272 - 282

Abstrakt

Abstract

In this paper, the treatment efficiency of a small-scale wastewater treatment plant (WWTP) with activated sludge was analysed in order to examine the impact of variations in the composition of incoming raw municipal wastewater. The characteristics of the wastewater were analysed with respect to COD, BOD5 and TSS values and loading during the two years, 2018 and 2019. The mixed liquid suspended solid (MLSS), sludge volume index (SVI), food to microorganism ratio (F/M), sludge age and hydraulic retention time (HRT) were used for evaluation of the performance of WWTP. Removal percentage is in the order of TSS > BOD5 > COD during 2018, while in 2019 is in the order BOD5 > TSS > COD. However, better values of removal efficiency for COD, BOD and TSS are obtained in 2019, which is connected to lower oscillation values of MLSS and SVI index. Biodegradability ratio of raw and treated wastewater, plant reliability factor (RF) and equivalent number of inhabitant (ENI) were determined. In addition, the economic cost of small-scale wastewater treatment plant (WWTP) with activated sludge was evaluated and discussed.

Słowa kluczowe

  • physicochemical indicators
  • wastewater treatment plant
  • activated sludge
  • sludge volume index
  • plant reliability factor
Otwarty dostęp

Climate change adaptation strategies by rice processors in Ebonyi State, Nigeria

Data publikacji: 17 Oct 2022
Zakres stron: 283 - 290

Abstrakt

Abstract

The paper examined adaptation strategies used by rice processors in Ebonyi State to manage climate risks. The paper used random sampling technique to select respondents and questionnaire was used to collect data from the respondents. Cross-sectional data collected from 98 rice processors were analysed using descriptive statistics and multivariate probit regression model. The results indicated that majority of the rice processors perceived prolonged dry season and increased rainfall intensity as the main climate risks in the state. Livelihood diversification, storing of paddy, and reliance on climate information were the major adaptation strategies used by the rice processors to manage the climate risks. The main determinants of climate change adaptation strategies of rice processors were education, membership of cooperative societies, income, training on rice processing and climate risk management, experience of climate hazards, and ownership of assets. The processors faced various barriers to adoption which are mainly related to capital needs, competition from foreign brands, access to basic infrastructure and roads and information, high cost of labour. It is recommended that government support be given to the rice producing communities in terms of basic infrastructure and policies to protect the industry. Also, regular workshops/trainings should be held to train processors on best climate risk management practices and encourage registration of processor cooperatives/relevant associations.

Słowa kluczowe

  • rice processing
  • adaptation
  • cross-sectional data
  • multivariate probit regression
  • barriers
  • Nigeria
Otwarty dostęp

Definition of hot-spots to reduce the nitrogen losses from agricultural land to groundwater in Slovakia

Data publikacji: 17 Oct 2022
Zakres stron: 291 - 300

Abstrakt

Abstract

Agriculture is a significant contributor to nitrate pollution of groundwater which in many cases serves as a source of drinking water. Therefore, targeted reduction of nitrogen leaching losses is fully justified to address this issue. The aim of the study was to define the areas of utilized agricultural land (UAL) in Slovakia, where a nitrogen surplus needs to be reduced. Using the average values of leachable nitrogen in the period 2015-2018 and the long-term amount of percolated water, the nitrate concentration in leachate was calculated. To ensure that agricultural activities will contribute to the gradual reduction of nitrate concentration in groundwater, the nitrate concentration in leachate of 40 mg L-1 was chosen as the target value. This concentration was exceeded at 11.7% of the UAL area. The average indicative amount of nitrogen in industrial fertilizers that needs to be reduced to achieve a stricter nitrate concentration in the leachate in these hot-spots is 16 kg ha-1 with the proviso that in two districts this value exceeds 30 kg ha-1.

Słowa kluczowe

  • Nitrates Directive
  • groundwater pollution
  • vulnerable zones
  • nitrogen surplus
  • nitrate concentration
  • leachate

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