Mining and smelting processes are among the key sources of soil contamination by heavy metals resulting in dramatic disturbances and loss of biodiversity. Native plants growing naturally in hostile mining environments can be used for management, decontamination and possible rehabilitation of polluted soils. These plants are either excluders or accumulators based on their Bioaccumulation Factors (BAF). This, therefore requires identification of native plants that are able to accumulate heavy metals in their plant tissues at concentrations higher than that in the soil in which they are growing. This study investigated the phytoremediation potential of indigenous plants growing at the tailings dams of Nchanga Mine in Chingola, Zambia. TD4 and a site 50 m away from TD4 were sampled as Sampling Areas One (1) and Two (2), respectively. TD4 was divided into four quadrants and three plots from each quadrant were randomly sampled. Three plots from each of the two quadrants from Sampling Area Two were also sampled. Composite soil samples were collected from the plots and a total of 175 individuals of 16 grass and herbaceous plant species were collected and analysed. Atomic Absorption Spectrophotometry was used to determine the concentrations of Copper (Cu) and Zinc (Zn) in the soils and plant specimens. The findings of the study showed that the concentrations of Cu and Zn in the soil ranged from 891.41 mg/kg to 15,617.47 mg/kg and 20.73 mg/kg to 96.85 mg/kg, respectively. Arthraxonquartinianus had the highest concentration of Cu (1016.8 mg/kg) while Cyperusrotundus had the lowest (29.35 mg/kg). Arthraxonquartinianus had the highest concentration of Zn (192.8 mg/kg) and Crinum had the lowest (28.24 mg/kg). BAF values for Cu were less than 1 in all the plants and BAF values for Zn were highest in Arthraxonquartinianus (10.77) with Crinum having the lowest BAF of 0.01. The Bioaccumulation Factors indicated that all the plant species studied are Cu excluders; and with the exception of Crinum, all were Zn accumulators and Arthraxonquartinianus, a hyperaccumulator of Zn.
{"title":"Phytoremediation Potential of Indigenous Plants Growing at Nchanga Mine in Chingola, Zambia","authors":"Lupupa Kachenga, H. Chabwela, K. Mwauluka","doi":"10.4236/oje.2020.102004","DOIUrl":"https://doi.org/10.4236/oje.2020.102004","url":null,"abstract":"Mining and smelting processes are among the key sources of soil contamination by heavy metals resulting in dramatic disturbances and loss of biodiversity. Native plants growing naturally in hostile mining environments can be used for management, decontamination and possible rehabilitation of polluted soils. These plants are either excluders or accumulators based on their Bioaccumulation Factors (BAF). This, therefore requires identification of native plants that are able to accumulate heavy metals in their plant tissues at concentrations higher than that in the soil in which they are growing. This study investigated the phytoremediation potential of indigenous plants growing at the tailings dams of Nchanga Mine in Chingola, Zambia. TD4 and a site 50 m away from TD4 were sampled as Sampling Areas One (1) and Two (2), respectively. TD4 was divided into four quadrants and three plots from each quadrant were randomly sampled. Three plots from each of the two quadrants from Sampling Area Two were also sampled. Composite soil samples were collected from the plots and a total of 175 individuals of 16 grass and herbaceous plant species were collected and analysed. Atomic Absorption Spectrophotometry was used to determine the concentrations of Copper (Cu) and Zinc (Zn) in the soils and plant specimens. The findings of the study showed that the concentrations of Cu and Zn in the soil ranged from 891.41 mg/kg to 15,617.47 mg/kg and 20.73 mg/kg to 96.85 mg/kg, respectively. Arthraxonquartinianus had the highest concentration of Cu (1016.8 mg/kg) while Cyperusrotundus had the lowest (29.35 mg/kg). Arthraxonquartinianus had the highest concentration of Zn (192.8 mg/kg) and Crinum had the lowest (28.24 mg/kg). BAF values for Cu were less than 1 in all the plants and BAF values for Zn were highest in Arthraxonquartinianus (10.77) with Crinum having the lowest BAF of 0.01. The Bioaccumulation Factors indicated that all the plant species studied are Cu excluders; and with the exception of Crinum, all were Zn accumulators and Arthraxonquartinianus, a hyperaccumulator of Zn.","PeriodicalId":265480,"journal":{"name":"Open Journal of Ecology","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128822862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Eve Bohnett, T. Hoctor, D. Hulse, B. Ahmad, Bernardo Niebuhr, R. Morato
Background Machine learning (ML) methods and remote sensing data were used to build multi-level multi-scale resource selection models and predictive maps onto the extended landscape for jaguars (Panthera onca) in the Brazilian Pantanal. Objectives were to compare multiple predictive modeling and exploratory modeling approaches. Included in the analysis, multi-scale raster grains (30m, 90m, 180m, 360m, 720m, 1440m), GPS collaring temporal levels (point, path, and step) and model data structural levels (group, individual, case-control).Methods Multi-scale multi-level data subsets were fit with explanatory and predictive statistical methods. Conditional logistic regression, generalized additive modeling (GAM), and classification regression trees, such as random forests (RF) and gradient boosted regression tree (GBM) were compared for their utility to the study. Model evaluation, using training and testing data in a k-fold cross-validation approach, determined the AUC, Kappa, and TSS for model evaluation and comparison. · Results Results indicated that the multi-level, multi-scale techniques improved model outputs. Overall, larger level models and those that used multi-scale raster grains showed the best model evaluation. The highest-ranked model was the multi-scale path selection function GBM and was one of the broadest levels of data. ·Conclusions Results indicated that multi-level, multi-scale models produced mixed results of applicability across models and levels. The identification of the appropriate temporal scale and statistical model needs careful consideration in predictive mapping efforts.
{"title":"Multi-Level, Multi-Scale Modeling and Predictive Mapping for Jaguars in the Brazilian Pantanal.","authors":"Eve Bohnett, T. Hoctor, D. Hulse, B. Ahmad, Bernardo Niebuhr, R. Morato","doi":"10.21203/rs.2.23193/v1","DOIUrl":"https://doi.org/10.21203/rs.2.23193/v1","url":null,"abstract":"\u0000 Background Machine learning (ML) methods and remote sensing data were used to build multi-level multi-scale resource selection models and predictive maps onto the extended landscape for jaguars (Panthera onca) in the Brazilian Pantanal. Objectives were to compare multiple predictive modeling and exploratory modeling approaches. Included in the analysis, multi-scale raster grains (30m, 90m, 180m, 360m, 720m, 1440m), GPS collaring temporal levels (point, path, and step) and model data structural levels (group, individual, case-control).Methods Multi-scale multi-level data subsets were fit with explanatory and predictive statistical methods. Conditional logistic regression, generalized additive modeling (GAM), and classification regression trees, such as random forests (RF) and gradient boosted regression tree (GBM) were compared for their utility to the study. Model evaluation, using training and testing data in a k-fold cross-validation approach, determined the AUC, Kappa, and TSS for model evaluation and comparison. · Results Results indicated that the multi-level, multi-scale techniques improved model outputs. Overall, larger level models and those that used multi-scale raster grains showed the best model evaluation. The highest-ranked model was the multi-scale path selection function GBM and was one of the broadest levels of data. ·Conclusions Results indicated that multi-level, multi-scale models produced mixed results of applicability across models and levels. The identification of the appropriate temporal scale and statistical model needs careful consideration in predictive mapping efforts.","PeriodicalId":265480,"journal":{"name":"Open Journal of Ecology","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128114678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Water is life and access to clean drinking water is a fundamental human right. For human health, drinking water standards and guidelines have been developed to ensure their quality. Waterborne parasites are a great challenge and cause many diseases for humans. Thus, continuous monitoring of drinking water from the competent authorities in search of pollutants is required. The safety of drinking water for the growing population can be ensured by the correct use of water treatment technologies. Cryptosporidium is the first parasite to cause concern to health officials in the world. Also, Naegleria fowleri causes fatal cerebral infection, Acanthamoeba species that cause both cerebral and corneal disease; and Giardia which has heightened world concerns because of its severity. This study is based on highlighting on drinking water quality guidelines and standards published by the World Health Organization and some countries, especially Egypt. A growing concern globally after the scientists revealed the effects of polluted drinking water. So, a large number of the population is at risk of water pollution for the purpose of human access to clean drinking water and other uses.
{"title":"Parasitic Contamination of Drinking Water and Egyptian Standards for Parasites in Drinking Water","authors":"W. Hikal","doi":"10.4236/oje.2020.101001","DOIUrl":"https://doi.org/10.4236/oje.2020.101001","url":null,"abstract":"Water is life and access to clean drinking water is a fundamental human right. For human health, drinking water standards and guidelines have been developed to ensure their quality. Waterborne parasites are a great challenge and cause many diseases for humans. Thus, continuous monitoring of drinking water from the competent authorities in search of pollutants is required. The safety of drinking water for the growing population can be ensured by the correct use of water treatment technologies. Cryptosporidium is the first parasite to cause concern to health officials in the world. Also, Naegleria fowleri causes fatal cerebral infection, Acanthamoeba species that cause both cerebral and corneal disease; and Giardia which has heightened world concerns because of its severity. This study is based on highlighting on drinking water quality guidelines and standards published by the World Health Organization and some countries, especially Egypt. A growing concern globally after the scientists revealed the effects of polluted drinking water. So, a large number of the population is at risk of water pollution for the purpose of human access to clean drinking water and other uses.","PeriodicalId":265480,"journal":{"name":"Open Journal of Ecology","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124835198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Orina, D. Onyango, H. Lung'ayia, A. Oduor, A. Sifuna, P. Otuya, R. Owigar, C. Kowenje, Sheban M. Hinzano
Lake Victoria the second largest fresh water body in the world located in East Africa is a shared resource between Kenya, Tanzania and Uganda and enjoys a wide range of streams and rivers from as far as Burundi and Rwanda. The lake has environmentally undergone physical, chemical and biological changes in the last four decades, particularly rise in its trophic condition and decline in oxygen level, which affects the water quality and fish population dynamics. This study therefore set out to determine the quality of water in selected fishing beaches of Lake Victoria, Kenya with a view to report the possible pollution levels. pH was highest at Nyamasari and Kotieno (9.3 ± 0.1) and lowest at Nyachebe and Kichinjio (7.08 ± 0.1) whereas temperature was highest at Nyamasari (29.5°C ± 0.0°C) and lowest at Kichinjio (23.4°C ± 0.2°C). DO was highest at Kotieno (10.3 ± 0.2 mgL) and lowest at Seka (2.4 ± 0.1 mgL). Turbidity was highest at Uyoga (125.5 ± 0.90 NTU) and lowest at Osieko (2.7 ± 0.1 NTU). Ammoniacal nitrogen was highest at Dunga (1278.3 ± 0.8 μ∙gl-1) and lowest at Nyamasari (12.4 ± 0.8), all a factor of human activities, lake substratum and effluents from rivers and surface runoff. All parameters assessed showed significant differences across sampling sites and depth except pH which did not vary significantly with distance from lakeshore. Further, all parameters did not show a clear pattern with respect to distance from the lakeshore possibly due to adequate mixing in the gulf. There is a need for further water quality monitoring by seasons to inform policy decisions towards sustainable lake exploitation.
{"title":"Water Quality of Selected Fishing Beaches of Lake Victoria Kenyan Gulf","authors":"P. Orina, D. Onyango, H. Lung'ayia, A. Oduor, A. Sifuna, P. Otuya, R. Owigar, C. Kowenje, Sheban M. Hinzano","doi":"10.4236/oje.2020.101002","DOIUrl":"https://doi.org/10.4236/oje.2020.101002","url":null,"abstract":"Lake Victoria the second largest fresh water body in the world located in East Africa is a shared resource between Kenya, Tanzania and Uganda and enjoys a wide range of streams and rivers from as far as Burundi and Rwanda. The lake has environmentally undergone physical, chemical and biological changes in the last four decades, particularly rise in its trophic condition and decline in oxygen level, which affects the water quality and fish population dynamics. This study therefore set out to determine the quality of water in selected fishing beaches of Lake Victoria, Kenya with a view to report the possible pollution levels. pH was highest at Nyamasari and Kotieno (9.3 ± 0.1) and lowest at Nyachebe and Kichinjio (7.08 ± 0.1) whereas temperature was highest at Nyamasari (29.5°C ± 0.0°C) and lowest at Kichinjio (23.4°C ± 0.2°C). DO was highest at Kotieno (10.3 ± 0.2 mgL) and lowest at Seka (2.4 ± 0.1 mgL). Turbidity was highest at Uyoga (125.5 ± 0.90 NTU) and lowest at Osieko (2.7 ± 0.1 NTU). Ammoniacal nitrogen was highest at Dunga (1278.3 ± 0.8 μ∙gl-1) and lowest at Nyamasari (12.4 ± 0.8), all a factor of human activities, lake substratum and effluents from rivers and surface runoff. All parameters assessed showed significant differences across sampling sites and depth except pH which did not vary significantly with distance from lakeshore. Further, all parameters did not show a clear pattern with respect to distance from the lakeshore possibly due to adequate mixing in the gulf. There is a need for further water quality monitoring by seasons to inform policy decisions towards sustainable lake exploitation.","PeriodicalId":265480,"journal":{"name":"Open Journal of Ecology","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114283604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fils Mamert Onana, S. Z. Togouet, Antoine Arfao Tamsa, Nectaire Lié Nyamsi Tchatcho, S. Tchakonté, E. Koji, Armel William Yemtsa Yemeli, Abigaelle Natacha Sandrine Mouto Makong
In this study conducted in the coastal zone of Cameroon, biological indices and functional feeding groups of benthic macroinvertebrates were used to assess the health status of two urban streams. For a better diagnosis, two streams located in coastal forest zone were used as a reference. Benthic macroinvertebrates were sampled monthly over a 3-month period (from May to July 2017) in six urban stations and six forest stations. Measurements of the physicochemical variables were done simultaneously. Physicochemical analysis revealed that urban streams are strongly polluted with high content of decaying organic matters, while forest streams are slightly polluted as indicated by the Principal Component Analysis. Concerning benthic macroinvertebrates, urban streams are poorly diversified with the proliferation of taxa tolerant to water pollution and belonging to the functional feeding groups of collectors-gatherers. Inversely, forest streams are more diversified and dominated by sensitive taxa, most belonging to the functional feeding groups of predators and shredders. These marked differences between biological indices and feeding mode of benthic macroinvertebrates in forest and urban rivers confirm the reliability of benthic macroinvertebrates as good indicators of freshwater ecosystem in the coastal zone of Cameroon.
{"title":"Comparing Freshwater Benthic Macroinvertebrate Communities in Forest and Urban Streams of the Coastal Ecological Region of Cameroon","authors":"Fils Mamert Onana, S. Z. Togouet, Antoine Arfao Tamsa, Nectaire Lié Nyamsi Tchatcho, S. Tchakonté, E. Koji, Armel William Yemtsa Yemeli, Abigaelle Natacha Sandrine Mouto Makong","doi":"10.4236/oje.2019.912034","DOIUrl":"https://doi.org/10.4236/oje.2019.912034","url":null,"abstract":"In this study conducted in the coastal zone of Cameroon, biological indices and functional feeding groups of benthic macroinvertebrates were used to assess the health status of two urban streams. For a better diagnosis, two streams located in coastal forest zone were used as a reference. Benthic macroinvertebrates were sampled monthly over a 3-month period (from May to July 2017) in six urban stations and six forest stations. Measurements of the physicochemical variables were done simultaneously. Physicochemical analysis revealed that urban streams are strongly polluted with high content of decaying organic matters, while forest streams are slightly polluted as indicated by the Principal Component Analysis. Concerning benthic macroinvertebrates, urban streams are poorly diversified with the proliferation of taxa tolerant to water pollution and belonging to the functional feeding groups of collectors-gatherers. Inversely, forest streams are more diversified and dominated by sensitive taxa, most belonging to the functional feeding groups of predators and shredders. These marked differences between biological indices and feeding mode of benthic macroinvertebrates in forest and urban rivers confirm the reliability of benthic macroinvertebrates as good indicators of freshwater ecosystem in the coastal zone of Cameroon.","PeriodicalId":265480,"journal":{"name":"Open Journal of Ecology","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133775102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Long-term data record of Phytoplankton (Peridinium, Cyanophyta, Chlorophyta, Diatoms) dynamics in Lake Kinneret was evaluated comparatively with hydrological parameters. The hydrological features were found to be correlated with algal biomass distribution. Consequently, the best representor of the hydrological trait, Residence Time, is suggested to be a key parameter controlling algal dynamics.
{"title":"Relation Significance between Hydrological Residence Time and Phytoplankton Dynamics in Lake Kinneret (Israel)","authors":"M. Gophen","doi":"10.4236/oje.2019.911031","DOIUrl":"https://doi.org/10.4236/oje.2019.911031","url":null,"abstract":"Long-term data record of Phytoplankton (Peridinium, Cyanophyta, Chlorophyta, Diatoms) dynamics in Lake Kinneret was evaluated comparatively with hydrological parameters. The hydrological features were found to be correlated with algal biomass distribution. Consequently, the best representor of the hydrological trait, Residence Time, is suggested to be a key parameter controlling algal dynamics.","PeriodicalId":265480,"journal":{"name":"Open Journal of Ecology","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125473969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ecosystems in arid regions play a pivotal role in providing services to vulnerable environments with considerable challenges including extreme temperatures, low precipitation, variable climate change, and infertile soil. The countries of the arid regions are facing more challenges due to land degradation, biodiversity loss, the scarcity of water and food resources, and protecting their inhabitant’s public health. In many cases, policymakers in these countries are aware of the challenges, but they are seeking through scientific communities to develop clear sustainability and resiliency plans. Due to the complexity associated with arid ecosystem services, the scientist communities are still focusing on the development of integrated ecosystem management approaches. Within this line of commitment to our future generation, the paper in hand presents a framework for an Integrated Ecosystem Sustainability Approach (IESA). The core of this nexus approach is to understand and quantify the interlinkages between the ecosystem components, internal and external stresses, and society needs. The paper also identifies the key gaps to be considered when applying the IESA approach to arid ecosystem management plans.
{"title":"Integrated Ecosystem Sustainability Approach: Toward a Holistic System of Thinking of Managing Arid Ecosystems","authors":"M. Abdullah, A. Assi, N. B. Asadalla","doi":"10.4236/oje.2019.911032","DOIUrl":"https://doi.org/10.4236/oje.2019.911032","url":null,"abstract":"Ecosystems in arid regions play a pivotal role in providing services to vulnerable environments with considerable challenges including extreme temperatures, low precipitation, variable climate change, and infertile soil. The countries of the arid regions are facing more challenges due to land degradation, biodiversity loss, the scarcity of water and food resources, and protecting their inhabitant’s public health. In many cases, policymakers in these countries are aware of the challenges, but they are seeking through scientific communities to develop clear sustainability and resiliency plans. Due to the complexity associated with arid ecosystem services, the scientist communities are still focusing on the development of integrated ecosystem management approaches. Within this line of commitment to our future generation, the paper in hand presents a framework for an Integrated Ecosystem Sustainability Approach (IESA). The core of this nexus approach is to understand and quantify the interlinkages between the ecosystem components, internal and external stresses, and society needs. The paper also identifies the key gaps to be considered when applying the IESA approach to arid ecosystem management plans.","PeriodicalId":265480,"journal":{"name":"Open Journal of Ecology","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122040184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A nonlinear dynamic simulative model has been discussed with variable cycles of entire world per capita ecological footprint taken from 1961 to 2003. The model was further classified and decomposed and extracted by the empirical mode decomposition (EMD) method. To deal with the problems proposed in the Living Planet Report 2006, three ecological footprint scenarios are presented. Simulative numerical values of the three global per capita (GPC) ecological footprint scenarios are also analyzed based on the simulative model. The results show that: 1) The clear varying cycle of global per capita EF growth is 4.6 years, 9.5 years, 19.5 years and 41 years over the last 42 years; 2) According to the business-as-usual scenario, if the global per capita increases positively with the constant growth, it is expected that GPC EF would be 3.262 gha in 2050. Assuming global per capita biocapacity (BC) to be 1.236 gha, global per capita ecological deficit (ED) would increase from 0.4 gha in 2003 to 2.026 gha in 2050; 3) The slow-shift scenario shows global per capita EF would decrease from 2.23 gha in 2003 to 1.619 gha in 2080 and 1.406 gha in 2100, if the negative annual change rate of it is 0.447 percent. Global per capita ED would decrease from 0.4 gha in 2003 to 0.222 gha in 2080 and 0.038 gha in 2100, if global per capita BC is 1.397 gha; 4) The rapid-reduction scenario depicts global per capita EF would decrease to 1.414 gha in 2050, if the negative annual change rate is 0.842% from 2003 to 2050. Assuming global per capita BC to be 1.461 gha, global per capita ecological reserve (ER) would be 0.047 gha, and overshoot would be eliminated in 2050. Global per capita EF would decrease to 1.054 gha in 2100, if the negative annual change rate is 0.438% from 2050 to 2100. Assuming global per capita BC to be 1.474 gha, GPC ER would be 0.420 gha. Then, wild species of the planet will be allocated nearly 28.5% of the planet’s biological productivity, which coincides with the results of Living Planet Report 2006.
{"title":"Multiple Scenarios Simulation of Global Ecological Footprint Based on Empirical Mode Decomposition Method","authors":"L. Xiang, Chengzhong Chen","doi":"10.4236/oje.2019.911033","DOIUrl":"https://doi.org/10.4236/oje.2019.911033","url":null,"abstract":"A nonlinear dynamic simulative model has been discussed with variable cycles of entire world per capita ecological footprint taken from 1961 to 2003. The model was further classified and decomposed and extracted by the empirical mode decomposition (EMD) method. To deal with the problems proposed in the Living Planet Report 2006, three ecological footprint scenarios are presented. Simulative numerical values of the three global per capita (GPC) ecological footprint scenarios are also analyzed based on the simulative model. The results show that: 1) The clear varying cycle of global per capita EF growth is 4.6 years, 9.5 years, 19.5 years and 41 years over the last 42 years; 2) According to the business-as-usual scenario, if the global per capita increases positively with the constant growth, it is expected that GPC EF would be 3.262 gha in 2050. Assuming global per capita biocapacity (BC) to be 1.236 gha, global per capita ecological deficit (ED) would increase from 0.4 gha in 2003 to 2.026 gha in 2050; 3) The slow-shift scenario shows global per capita EF would decrease from 2.23 gha in 2003 to 1.619 gha in 2080 and 1.406 gha in 2100, if the negative annual change rate of it is 0.447 percent. Global per capita ED would decrease from 0.4 gha in 2003 to 0.222 gha in 2080 and 0.038 gha in 2100, if global per capita BC is 1.397 gha; 4) The rapid-reduction scenario depicts global per capita EF would decrease to 1.414 gha in 2050, if the negative annual change rate is 0.842% from 2003 to 2050. Assuming global per capita BC to be 1.461 gha, global per capita ecological reserve (ER) would be 0.047 gha, and overshoot would be eliminated in 2050. Global per capita EF would decrease to 1.054 gha in 2100, if the negative annual change rate is 0.438% from 2050 to 2100. Assuming global per capita BC to be 1.474 gha, GPC ER would be 0.420 gha. Then, wild species of the planet will be allocated nearly 28.5% of the planet’s biological productivity, which coincides with the results of Living Planet Report 2006.","PeriodicalId":265480,"journal":{"name":"Open Journal of Ecology","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125364355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The distributions of species in their habitats are constantly changing. This phenomenon is thought to be determined by species’ environmental tolerance and biotic interactions for limited resources and space. Consequently, predicting the future distribution of species is a major challenge in ecology. To address this problem, we use mathematical model to study the combined effects of biotic interactions (e.g. competition) and environmental factors on multiple species community assembly in a heterogenous environment. To gain insights into the dynamics of this ecological system, we perform both analytical and numerical analyses of the range margins of the species. We observe that the range margins of the species can be influenced by biotic interactions combined with environmental factors. Depending on the strength of biotic interactions, our model exhibits coexistence of species and priority effects; mediated by weak and intense biotic interactions respectively. We also show the existence of bifurcation points (i.e. the threshold values of competition coefficient) which lead to the presence—absence of different species. Thus, we suggest that adequate knowledge of biotic interactions and changes in the environments is important for effective maintenance of biodiversity and conservation management.
{"title":"The Roles of Biotic Interactions and Environmental Factors on Multispecies Dynamics","authors":"O. Omaiye, M. H. Mohd","doi":"10.4236/oje.2019.910028","DOIUrl":"https://doi.org/10.4236/oje.2019.910028","url":null,"abstract":"The distributions of species in their habitats are constantly changing. This phenomenon is thought to be determined by species’ environmental tolerance and biotic interactions for limited resources and space. Consequently, predicting the future distribution of species is a major challenge in ecology. To address this problem, we use mathematical model to study the combined effects of biotic interactions (e.g. competition) and environmental factors on multiple species community assembly in a heterogenous environment. To gain insights into the dynamics of this ecological system, we perform both analytical and numerical analyses of the range margins of the species. We observe that the range margins of the species can be influenced by biotic interactions combined with environmental factors. Depending on the strength of biotic interactions, our model exhibits coexistence of species and priority effects; mediated by weak and intense biotic interactions respectively. We also show the existence of bifurcation points (i.e. the threshold values of competition coefficient) which lead to the presence—absence of different species. Thus, we suggest that adequate knowledge of biotic interactions and changes in the environments is important for effective maintenance of biodiversity and conservation management.","PeriodicalId":265480,"journal":{"name":"Open Journal of Ecology","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115369959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In the last 40 years, threats to the survival of wild primate population have greatly increased. Globally, primate population is severely threatened with extinction especially due to habitat loss from conversion of forest areas to farmland and/or unsustainable logging. There is paucity of information on the population density and abundance of Mona monkeys in Omo Forest Reserve. The population density and distribution of Mona monkeys were conducted in two forest blocks of Omo Forest Reserve (OFR). The objective of the study therefore, is to determine the population density and distribution of Mona monkey, and ascertain the presence of other primate species in sympatric relationship with the monkey. The line transect sampling method was used for the enumeration. Data were collected from seven (7) transects randomly selected from two forest blocks; the Elephant Sanctuary (4) and the Strict Nature Reserve (3). Other primate species were considered to be sympatric with Mona monkeys if they were encountered within 20 m proximity range with the target species. Data on threat of human activities were collected in Omo Forest Reserve based on four major categories (Hunting/Poaching, Logging, Farming, and Collection of Non-Timber Forest Products). Analysis was carried out using IBM SPSS Statistics 20 to determine population density estimate and the relative density in the two forest blocks. The field work took 30 days each, in September, 2015 and March 2016 that covered both seasons. Results revealed that a total number of 57 Mona monkeys with density of 0.44 km−2 in the entire reserve were sighted during the survey. The relative density across the two forest blocks surveyed in the forest reserve revealed that Mona monkeys were present in both the Elephant Sanctuary (ES) (n = 42) and Strict Nature Reserve (SNR) (n = 15) with density of 0.27 km−2 and 0.18 km−2, respectively. The species were observed to be more active during morning surveys than in the evening surveys, with densities of 0.77 km−2 and 0.4 km−2 recorded, respectively. The mean encounter rates for the species were 3.31 km−1 and 1.5 km−1 for morning and evening surveys, respectively.
{"title":"Preliminary Study of the Population Density of Mona Monkeys (Cercopithecus mona) in Omo Forest Reserve","authors":"J. Uloko, G. Lameed","doi":"10.4236/oje.2019.910027","DOIUrl":"https://doi.org/10.4236/oje.2019.910027","url":null,"abstract":"In the last 40 years, threats to the survival of wild primate population have greatly increased. Globally, primate population is severely threatened with extinction especially due to habitat loss from conversion of forest areas to farmland and/or unsustainable logging. There is paucity of information on the population density and abundance of Mona monkeys in Omo Forest Reserve. The population density and distribution of Mona monkeys were conducted in two forest blocks of Omo Forest Reserve (OFR). The objective of the study therefore, is to determine the population density and distribution of Mona monkey, and ascertain the presence of other primate species in sympatric relationship with the monkey. The line transect sampling method was used for the enumeration. Data were collected from seven (7) transects randomly selected from two forest blocks; the Elephant Sanctuary (4) and the Strict Nature Reserve (3). Other primate species were considered to be sympatric with Mona monkeys if they were encountered within 20 m proximity range with the target species. Data on threat of human activities were collected in Omo Forest Reserve based on four major categories (Hunting/Poaching, Logging, Farming, and Collection of Non-Timber Forest Products). Analysis was carried out using IBM SPSS Statistics 20 to determine population density estimate and the relative density in the two forest blocks. The field work took 30 days each, in September, 2015 and March 2016 that covered both seasons. Results revealed that a total number of 57 Mona monkeys with density of 0.44 km−2 in the entire reserve were sighted during the survey. The relative density across the two forest blocks surveyed in the forest reserve revealed that Mona monkeys were present in both the Elephant Sanctuary (ES) (n = 42) and Strict Nature Reserve (SNR) (n = 15) with density of 0.27 km−2 and 0.18 km−2, respectively. The species were observed to be more active during morning surveys than in the evening surveys, with densities of 0.77 km−2 and 0.4 km−2 recorded, respectively. The mean encounter rates for the species were 3.31 km−1 and 1.5 km−1 for morning and evening surveys, respectively.","PeriodicalId":265480,"journal":{"name":"Open Journal of Ecology","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115434158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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