The Tlemcen region is located in north-western Algeria and is characterized by a semi-arid bioclimate. An approach to the diversity of the malacofauna associated with Salvia officinalis was carried out in three statio...The Tlemcen region is located in north-western Algeria and is characterized by a semi-arid bioclimate. An approach to the diversity of the malacofauna associated with Salvia officinalis was carried out in three stations belonging to this area from February to June 2015. The specific richness of the Gastropods is 9 divided into three families: Milacidae, Helicidae and Subulinidae. The second includes two subfamilies including that of Helicinae and that of Helicellinae. Two species are constant, 01 is incidental and the 06 others are very accidental. The relative importance of snails fluctuates according to the stations and according to the months and the seasons. In winter, in the first station the malacological richness is equal to 6. In February, the specific richness is relatively important in the 2nd station with a value equal to 7. Milax nigricans (Milacidae) has a frequency of 10% in station 1 and has a density of 0.1 in this same station. It is absent in the other two stations. Euparypha pisana has a frequency of 60% in station 3 and an abundance of 0.57 in this same station.展开更多
Ⅰ.Introduction1) The People’s Park Square isShanghai’s best known land-mark and is the traditionalcenter of its cultural andrecreational facilities as wellas an extension of Shanghai’sprime commercial area.Thearea...Ⅰ.Introduction1) The People’s Park Square isShanghai’s best known land-mark and is the traditionalcenter of its cultural andrecreational facilities as wellas an extension of Shanghai’sprime commercial area.Thearea contains of Shanghai’sprime commercial area.Thearea contains a number ofbuildings of significant archi-tectural and heritage merit.展开更多
Accessibility is a factor affecting national park visitation.However,the effect of accessibility on national park visitation is not fully understood.This paper examines the relationship between U.S.national park visit...Accessibility is a factor affecting national park visitation.However,the effect of accessibility on national park visitation is not fully understood.This paper examines the relationship between U.S.national park visitation and accessibility.First,the global and local accessibility indexes of each park unit are computed based on an accessibility model that takes into account the surrounding population and its proximity to the park unit.Integrated in the model is a distance decay coefficient that is derived from U.S.national park visitor surveys and therefore pertinent to the case of study.Then correlation analysis is performed between park visitation and accessibility based on park types,regions,and visitation types.Results show that total visitation is positively related to accessibility in National Memorials,Military Parks and Battlefield Parks/Sites but negatively related to accessibility in national parks and national monuments.However,recreational overnight stay visits are commonly negatively correlated to accessibility for almost all park types.Moreover,local accessibility index displays enhanced correlation coefficients with improved significance levels in many categories of analysis.Results suggest that historical/cultural national parks which often show positive correlations tend to attract more local visitors,but nature-based parks which mainly show negative correlations tend to attract more distant visitors.展开更多
文摘The Tlemcen region is located in north-western Algeria and is characterized by a semi-arid bioclimate. An approach to the diversity of the malacofauna associated with Salvia officinalis was carried out in three stations belonging to this area from February to June 2015. The specific richness of the Gastropods is 9 divided into three families: Milacidae, Helicidae and Subulinidae. The second includes two subfamilies including that of Helicinae and that of Helicellinae. Two species are constant, 01 is incidental and the 06 others are very accidental. The relative importance of snails fluctuates according to the stations and according to the months and the seasons. In winter, in the first station the malacological richness is equal to 6. In February, the specific richness is relatively important in the 2nd station with a value equal to 7. Milax nigricans (Milacidae) has a frequency of 10% in station 1 and has a density of 0.1 in this same station. It is absent in the other two stations. Euparypha pisana has a frequency of 60% in station 3 and an abundance of 0.57 in this same station.
文摘Ⅰ.Introduction1) The People’s Park Square isShanghai’s best known land-mark and is the traditionalcenter of its cultural andrecreational facilities as wellas an extension of Shanghai’sprime commercial area.Thearea contains of Shanghai’sprime commercial area.Thearea contains a number ofbuildings of significant archi-tectural and heritage merit.
基金supported by the National Nature Science Foundation of China (Grant No. 41401604)the Central Universities Fund Project of Southwest Minzu University (Grant No. 2019SYB07)
文摘Accessibility is a factor affecting national park visitation.However,the effect of accessibility on national park visitation is not fully understood.This paper examines the relationship between U.S.national park visitation and accessibility.First,the global and local accessibility indexes of each park unit are computed based on an accessibility model that takes into account the surrounding population and its proximity to the park unit.Integrated in the model is a distance decay coefficient that is derived from U.S.national park visitor surveys and therefore pertinent to the case of study.Then correlation analysis is performed between park visitation and accessibility based on park types,regions,and visitation types.Results show that total visitation is positively related to accessibility in National Memorials,Military Parks and Battlefield Parks/Sites but negatively related to accessibility in national parks and national monuments.However,recreational overnight stay visits are commonly negatively correlated to accessibility for almost all park types.Moreover,local accessibility index displays enhanced correlation coefficients with improved significance levels in many categories of analysis.Results suggest that historical/cultural national parks which often show positive correlations tend to attract more local visitors,but nature-based parks which mainly show negative correlations tend to attract more distant visitors.
