Species composition and minimum sampling area of a riparian mixed broadleaved-Korean pine forest in Changbai Mountain Nature Reserve

Riparian areas are unique although often small component of the overall watershed landscape. The structure of riparian forests along Erdaobai River on the north slope of Changbai Mountain were investigated by using field data collected from eight sampling transects perpendicular to the Erdaobai River channel. Two kinds of species-area saturation curves were used to examine the relationship between species number and minimum sampling area. The results showed that riparian gymnosperms accounted for a high proportion of all gymnosperms in the Changbai Mountain Nature Reserve while riparian ferns and angiosperms accounted for a relatively low proportion. The average minimum sampling areas of riparian forest that included 60%, 80%, and 90% of the community species pool were about 85, 185, and 328 m 2 , respectively; while those for nonriparian forest were about 275, 390, and 514 m 2 , correspondingly.

A Simulation Study for Typical Design Rule Patterns in 5 nm Logic Process with EUV Photolithographic Process

5 nm logic technology node is believed to be the first node that will adopt Extremely Ultra-Violet(EUV)lithography on a large scale.We have done a simulation study for typical 5 nm logic design rule patterns.In a 5 nm logic photo process,the most appropriate layers for the EUV lithography are the cut layers,metal layers,and via layers.Generally speaking,critical structures in a lithography process are semi-dense patterns,also known as the“forbidden pitch”patterns,the array edge structures,tip-to-tip structures,tip-to-line structures(under 2D design rules),the minimum area structures,the bi-lines,tri-lines,…,etc.Compared to that from the 193 nm immersion process,the behaviors for the above structures are different.For example,in the 193 nm immersion process,the minimum area is about 2~3 times that of minimum pixel squared,while in EUV photolithographic process,the minimum achievable area is found to be significantly larger.In the simulation,we have kept aware of the stochastics impact due to drastically reduced number of photons absorbed compared to the DUV process,the criteria used for various structures of image contrast are tightened.For example,in 193 nm immersion lithography,we have usually set the minimum Exposure Latitude(EL)for the poly layer,the metal layer,and tip-to-tip pattern,respectively,at 18%,13%,and 10%.However,in EUV lithography,reasonable targets for the minima are,respectively,>18%,18%,and 13%.We have also studied the aberration and shadowing impact to the above design rule structures.We will present the results of our work and our explanations.

Apparent Electrical Conductivity of Porous Titanium Prepared by the Powder Metallurgy Method

Porous titanium is produced by thepowder metallurgy method. Dependence of the electrical conductivity on the porosity and pore size is investigated and the experimental results are compared with a number of models. It is found that the minimum solid area model could be successfully applied to describe the relationship between the electrical conductivity and the porosity of porous titanium. This kind of conductivity increases with increasing pore sizes.

Tensile Characteristics Evaluation of Corroded Reinforcing Bars Extracted from Actual Structures

The analysis used simple finite elements is performed to simulate the tensile behavior of corroded reinforcing bars extracted from three actual concrete structures. The cross-sectional area of the elements is set to have the actual distribution measured by 3D laser scanner system. The variable factor in the analysis is the length of the elements. The analysis results show that the length of the elements has a major influence on the deformation capacity after yielding. The calculated stress-strain curves, obtained using the elements with a length that is 2 times the bar diameter, are in good agreement with the tensile test results. The calculated stress-strain curves are modeled using a bi-linear model to facilitate the FEA （finite element analysis） of an overall concrete structure. From the analysis results, both the tensile and yield strengths decrease in proportion to the reduction of the minimum cross-sectional area of corroded bars. The ultimate strain has a remarkable decrement as the reduction of the minimum cross-sectional area. Formulas for determining these values are proposed as a function of the decrement ratio of the minimum cross-sectional area of a corroded bar.

The current state of the plant diversity in the Tlemcen region(Northwest Algeria)

Tlemcen region is characterized by a Mediterranean climate, with a remarkable vegetal cover. The latter is influenced by the anthropozoological action. For that, we realized a phytoecological study based on the minimum area classical method [1] which allows us to have a good overview on plant biodiversity and better analyze and interpret the vegetation at different levels (systematic composition;biological, morphological and biogeographical characterizations;stratification;and plant species inventory which we hope comprehensive). The results show that our ecosystems are disrupted because therophytisation, before last vegetation dynamics element [2], settles giving up a few feet of cork and holm oaks species of ancient forest.

Selective extinction and habitat nestedness are the main drivers of lizard nestedness in the Zhoushan Archipelago

Nested subset pattern(nestedness)is an important part of the theoretical framework of island biogeography and community ecology.However,most previous studies often used nestedness metrics or randomization algorithms that are vulnerable to type I error.In this study,we inves-tigated the nestedness of lizard assemblages on 37 islands in the Zhoushan Archipelago,China.We used the line-transect method to survey species occurrence,abundance,and habitat types of lizards on 37 islands during 2 breeding seasons in 2021 and 2022.We applied the nested metric WNODF and the conservative rc null model to control for type I error and quantify the significance of nestedness.Spearman rank cor relations were used to evaluate the role of 4 habitat variables(island area,2 isolation indices,and habitat diversity)and 4 ecological traits(body size,geographic range size,clutch size,and minimum area requirement)in generating nestedness.The results of WNODF analyses showed that lizard assemblages were significantly nested.The habitat-by-site matrix estimated by the program NODF was also significantly nested,support-ing the habitat nestedness hypothesis.The nestedness of lizard assemblages were significantly correlated with island area,habitat diversity.clutch size,and minimum area requirement.Overall,our results suggest that selective extinction and habitat nestedness were the main drivers of lizard nestedness in our system.In contrast,the nestedness of lizard assemblages was not due to passive sampling or selective colonization.To maximize the number of species preserved,our results indicate that we should protect both large islands with diverse habitats and species with largearea requirement and clutch size.

Nestedness and underlying processes of bird assemblages in Nanjing urban parks

Nestedness is an important pattern frequently reported for species assemblages on islands or fragmented systems.However,to date,there are few studies that comprehensively investigated faunal nestedness and underlying processes in urbanized landscapes.In this study,we examined the nestedness of bird assemblages and its underlying causal mechanisms in 37 urban parks in Nanjing,China.We used the line-transect method to survey birds from April 2019 to January 2020.We used the Weighted Nestedness metric based on Overlap and Decreasing Fill(WNODF)to estimate the nestedness of bird assemblages.We applied spearman partial correlation test to examine the relationships between nestedness ranks of sites and park characteristics(area,isolation,anthropogenic noise,number of habitat types,and building index),as well as between nestedness ranks of species and their ecological traits(body size,geographic range size,clutch size,minimum area requirement,dispersal ratio,and habitat specificity).We found that bird assemblages in urban parks were significantly nested.Park area,habitat diversity,building index,habitat specificity,and minimum area requirement of birds were significantly correlated with nestedness.Therefore,the nestedness of bird assemblages was caused by selective extinction,habitat nestedness,and urbanization.However,the nestedness of bird assemblages did not result from passive sampling,selective colonization,or human disturbance.Overall,to maximize the number of species preserved in our system,conservation priority should be given to parks with large area,rich habitat diversity,and less building index.From a species perspective,we should focus on species with large area requirement and high habitat specificity for their effective conservation.