Understanding the relationship between modern pollen and vegetation is crucial for interpreting fossil pollen records and assessing human impact on the environment,both of which are essential for effective environment...Understanding the relationship between modern pollen and vegetation is crucial for interpreting fossil pollen records and assessing human impact on the environment,both of which are essential for effective environmental management strategies.Despite numerous studies on fossil pollen records in the Rif landscape,research specifically focusing on modern pollen and its implications for understanding human impact on the natural landscape is notably lacking.This paper presents novel anthropogenic pollen indicators for the Rif Mountains and seeks to evaluate the gradients of human impact on the southern Mediterranean landscape.We employed a combination of modern pollen analysis,vegetation survey,and ordination techniques,incorporating various environmental and land-use variables.Canonical correspondence analysis(CCA)allowed us to evaluate the relationships between pollen types and environmental variables,helping us identify key anthropogenic pollen indicators associated with land use and human activities:Poaceae,Cannabist,Olea-t,and Asteraceae for cultivation;Brassicaceae,Genista-t,Poaceae,Asteraceae and Plantago-t,for grazing;Apiaceae,Urtica-t and Genista-t for slashing and burning.Additionally,an anthropogenic index score(AIS)was calculated for each sampled location.Correspondence analysis(CA)was then used to correlate each specific pollen type with levels of human impact as follows(a)low(e.g.,Cedrus atlantica-t,Quercus canariensis-t),(b)moderate(e.g.,Erica-t,Arbutus unedo-t,Eucalyptus-t),and(c)high(e.g.,Cannabis-t,Brassicaceae,Olea-t,Nicotiana-t).This paper enhances our comprehension of land-use dynamics and impact levels,providing essential insights for evaluating anthropogenic impact trends and human-induced changes in the Rif Mountains landscape.展开更多
In recent years,the ecological environment along highways in Tibetan Plateau has been severely affected due to the rapid construction of highways.In order to solve the problems of multiple indicators and inconsistent ...In recent years,the ecological environment along highways in Tibetan Plateau has been severely affected due to the rapid construction of highways.In order to solve the problems of multiple indicators and inconsistent criteria in the ecological impact assessment of highways,and to scientifically screen assessment indicators,the paper proposes a multi-round indicator screening method,which combines literature analysis,expert rating,and statistical analysis.Based on this screening method,normalized difference vegetation index,land surface temperature,elevation,and normalized difference soil index are screened out.Combined with multiple linear regression,an ecological impact assessment model is established and applied to ecological impact assessment of Gonghe-Yushu Expressway.The results show that the expressway construction is the first driving force for the deterioration of the ecological environment along the roadside,and its interference range on the desert grassland ecosystem is greater than that on the agroforestry system.The ecological environment within 150 m on both sides of the expressway should be protected.展开更多
文摘Understanding the relationship between modern pollen and vegetation is crucial for interpreting fossil pollen records and assessing human impact on the environment,both of which are essential for effective environmental management strategies.Despite numerous studies on fossil pollen records in the Rif landscape,research specifically focusing on modern pollen and its implications for understanding human impact on the natural landscape is notably lacking.This paper presents novel anthropogenic pollen indicators for the Rif Mountains and seeks to evaluate the gradients of human impact on the southern Mediterranean landscape.We employed a combination of modern pollen analysis,vegetation survey,and ordination techniques,incorporating various environmental and land-use variables.Canonical correspondence analysis(CCA)allowed us to evaluate the relationships between pollen types and environmental variables,helping us identify key anthropogenic pollen indicators associated with land use and human activities:Poaceae,Cannabist,Olea-t,and Asteraceae for cultivation;Brassicaceae,Genista-t,Poaceae,Asteraceae and Plantago-t,for grazing;Apiaceae,Urtica-t and Genista-t for slashing and burning.Additionally,an anthropogenic index score(AIS)was calculated for each sampled location.Correspondence analysis(CA)was then used to correlate each specific pollen type with levels of human impact as follows(a)low(e.g.,Cedrus atlantica-t,Quercus canariensis-t),(b)moderate(e.g.,Erica-t,Arbutus unedo-t,Eucalyptus-t),and(c)high(e.g.,Cannabis-t,Brassicaceae,Olea-t,Nicotiana-t).This paper enhances our comprehension of land-use dynamics and impact levels,providing essential insights for evaluating anthropogenic impact trends and human-induced changes in the Rif Mountains landscape.
基金supported by the National Natural Science Foundation of China(NSFC)(No.41801387)。
文摘In recent years,the ecological environment along highways in Tibetan Plateau has been severely affected due to the rapid construction of highways.In order to solve the problems of multiple indicators and inconsistent criteria in the ecological impact assessment of highways,and to scientifically screen assessment indicators,the paper proposes a multi-round indicator screening method,which combines literature analysis,expert rating,and statistical analysis.Based on this screening method,normalized difference vegetation index,land surface temperature,elevation,and normalized difference soil index are screened out.Combined with multiple linear regression,an ecological impact assessment model is established and applied to ecological impact assessment of Gonghe-Yushu Expressway.The results show that the expressway construction is the first driving force for the deterioration of the ecological environment along the roadside,and its interference range on the desert grassland ecosystem is greater than that on the agroforestry system.The ecological environment within 150 m on both sides of the expressway should be protected.
