Comparative assessment of different methods for using land-cover variables for distribution modelling of Salamandra salamandra longirotris

2012 ◽  
Vol 40 (1) ◽  
pp. 48-59 ◽  
Author(s):  
DAVID ROMERO ◽  
JESÚS OLIVERO ◽  
RAIMUNDO REAL
Keyword(s):  
Land Cover ◽  
Surface Area ◽  
Single Type ◽  
Negative Effects ◽  
Distribution Modelling ◽  
Unique Type ◽  
Herbaceous Crops ◽  
Different Types ◽  
Salamandra Salamandra ◽  
Variable Analysis

SUMMARYPredictive models are frequently used to define the most suitable areas for species protection or reintroduction. Land-cover variables can be used in different ways for distribution modelling. The surface area of a set of land-cover classes is often used, each land-cover presence/absence or the distance to them from any point of the study area can be preferred; multiple types of land-cover variables may be combined to produce a single model. This paper assesses whether different approaches to using land-cover variables may lead to different ecological conclusions when interpreted for conservation by focusing on the distribution of the salamader Salamandra salamandra longirostris, an endangered amphibian subspecies in the south of the Iberian Peninsula. Twenty-eight land-cover classes and another 42 environmental variables were used to construct four different models. Three models used a unique type of land-cover variable: either the presence of each class, the surface area of each class or the distance to each class, with all three variable types jointly entered in a fourth model. All models attained acceptable scores according to some criteria (discrimination, descriptive and predictive capacities, classification accuracy and parsimony); however most of the assessment parameters computed indicated a better performance of the models using either the surface area of land classes or the distance to them from every sampled square, compared to the model using class presences. The best scores were obtained with the fourth model, which combined different types of land-cover variables. This model suggested that oak forest fragmentation in favour of herbaceous crops and pastures may have negative effects on the distribution of S. s. longirostris. This was only partially suggested by the first three models, which considered a single type of land-cover variable, demonstrating the importance of considering a multi-variable analysis for conservation planning.

scholarly journals Ecological Connectivity in Agricultural Green Infrastructure:  Suggested Criteria for Fine Scale Assessment and Planning

Land ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 807
Author(s):  
Simone Valeri ◽  
Laura Zavattero ◽  
Giulia Capotorti
Keyword(s):  
Land Cover ◽  
Green Infrastructure ◽  
Rural Areas ◽  
Urban Areas ◽  
Landscape Heterogeneity ◽  
Agricultural Landscapes ◽  
Spatial Pattern Analysis ◽  
Fine Scale ◽  
Unique Type

In promoting biodiversity conservation and ecosystem service capacity, landscape connectivity is considered a critical feature to counteract the negative effects of fragmentation. Under a Green Infrastructure (GI) perspective, this is especially true in rural and peri-urban areas where a high degree of connectivity may be associated with the enhancement of agriculture multifunctionality and sustainability. With respect to GI planning and connectivity assessment, the role of dispersal traits of tree species is gaining increasing attention. However, little evidence is available on how to select plant species to be primarily favored, as well as on the role of landscape heterogeneity and habitat quality in driving the dispersal success. The present work is aimed at suggesting a methodological approach for addressing these knowledge gaps, at fine scales and for peri-urban agricultural landscapes, by means of a case study in the Metropolitan City of Rome. The study area was stratified into Environmental Units, each supporting a unique type of Potential Natural Vegetation (PNV), and a multi-step procedure was designed for setting priorities aimed at enhancing connectivity. First, GI components were defined based on the selection of the target species to be supported, on a fine scale land cover mapping and on the assessment of land cover type naturalness. Second, the study area was characterized by a Morphological Spatial Pattern Analysis (MSPA) and connectivity was assessed by Number of Components (NC) and functional connectivity metrics. Third, conservation and restoration measures have been prioritized and statistically validated. Notwithstanding the recognized limits, the approach proved to be functional in the considered context and at the adopted level of detail. Therefore, it could give useful methodological hints for the requalification of transitional urban–rural areas and for the achievement of related sustainable development goals in metropolitan regions.

The Analysis of Urban Road Traffic State Based on Kinds Floating Car Data

2014 ◽  
Vol 694 ◽  
pp. 80-84
Author(s):  
Xiao Tong Yin ◽  
Chao Qun Ma ◽  
Liang Peng Qu
Keyword(s):  
Road Traffic ◽  
Velocity Estimation ◽  
Least Square ◽  
Single Type ◽  
Estimation Model ◽  
Average Speed ◽  
Urban Road ◽  
Traffic State ◽  
Floating Car Data ◽  
Different Types

The analysis of the unban road traffic state based on kinds of floating car data, is based on the model and algorithm of floating car data preprocessing and map matching, etc. Firstly, according to the characteristics of the different types of urban road, the urban road section division has been carried on the elaboration and optimization. And this paper introduces the method of calculating the section average speed with single floating car data, also applies the dynamic consolidation of sections to estimate the section average velocity.Then the minimum sample size of floating car data is studied, and section average velocity estimation model based on single type of floating car data in the different case of floating car data sample sizes has been built. Finally, the section average speed of floating car in different types is fitted to the section average car speed by the least square method, using section average speed as the judgment standard, the grade division standard of urban road traffic state is established to obtain the information of road traffic state.

scholarly journals Not all biases are bad: equitable and inequitable biases in machine learning and radiology

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Mirjam Pot ◽  
Nathalie Kieusseyan ◽  
Barbara Prainsack
Keyword(s):  
Machine Learning ◽  
Human Error ◽  
Technical Problem ◽  
Social Dimension ◽  
Patient Treatment ◽  
Technical Solution ◽  
Negative Effects ◽  
Different Types ◽  
Human Decision

AbstractThe application of machine learning (ML) technologies in medicine generally but also in radiology more specifically is hoped to improve clinical processes and the provision of healthcare. A central motivation in this regard is to advance patient treatment by reducing human error and increasing the accuracy of prognosis, diagnosis and therapy decisions. There is, however, also increasing awareness about bias in ML technologies and its potentially harmful consequences. Biases refer to systematic distortions of datasets, algorithms, or human decision making. These systematic distortions are understood to have negative effects on the quality of an outcome in terms of accuracy, fairness, or transparency. But biases are not only a technical problem that requires a technical solution. Because they often also have a social dimension, the ‘distorted’ outcomes they yield often have implications for equity. This paper assesses different types of biases that can emerge within applications of ML in radiology, and discusses in what cases such biases are problematic. Drawing upon theories of equity in healthcare, we argue that while some biases are harmful and should be acted upon, others might be unproblematic and even desirable—exactly because they can contribute to overcome inequities.

Shape-Tailored TiO2 Photocatalysts Obtained in the Presence of Different Types of Carbon Materials

2021 ◽  
Vol 21 (4) ◽  
pp. 2360-2367
Author(s):  
Krisztina Vajda ◽  
Klára Hernádi ◽  
Cosmin Coteţ ◽  
Gábor Kovács ◽  
Zsolt Pap
Keyword(s):  
Carbon Materials ◽  
Uv Light ◽  
Carbon Aerogel ◽  
Low Carbon ◽  
Negative Effects ◽  
Tio2 Photocatalysts ◽  
Uv Light Irradiation ◽  
Specific Morphology ◽  
Different Types ◽  
Photocatalytic Applications

Titania and carbon materials are intensively studied in composite materials including photocatalytic applications. Both positive and negative effects were described in the literature, including charge separation, adsorption enhancement and short-circuiting of the photoelectrons as well. In the present study a more sparsely investigated properties of carbon materials will be highlighted, namely their role as crystallization promoters for titania, during hydrothermal synthesis of the composites. Therefore, carbon nanotubes, carbon coils, activated carbon, graphite and carbon aerogel was used to identify the importance of carbon during the time dependent crystallization of titanium dioxide. The crystal phase composition, morphology, optical properties and photocatalytic activity was followed, and it was found that the anatase and rutile crystallization depended on the used carbon material. The morphology of the particles varied from single anatase sheet-like crystals to hierarchical microball-like structures, while in some cases no specific morphology was observed. Furthermore, it was found that despite the low carbon content (2 wt.%) and microcrystalline structure of TiO2 the composites were proven to be efficient in the degradation of Rhodamine B under UV light irradiation.

scholarly journals Evolution de l’occupation des sols dans la partie Nord du Dallol Bosso, départements de Filingué et Balleyara, région de Tillabéri-Niger

2018 ◽  
Vol 14 (30) ◽  
pp. 391
Author(s):  
Issoufou Maigary ◽  
Boureïma Ousmane ◽  
Ado Dankarami
Keyword(s):  
Land Use ◽  
Land Cover ◽  
Climate Variability ◽  
Surface Area ◽  
Satellite Image ◽  
Total Surface Area ◽  
Land Use Land Cover ◽  
Climate Variability And Change ◽  
Natural Plant ◽  
Balanced Development

The departments of Filingué and Balleyara, which are our study area, are located in the northern part of Dallol Bosso, Tillabéri region in western Niger. This study area is circumscribed between 13 ° 35 'and 14 ° 40' north latitudes and 2 ° 50 'and 3 ° 30' East longitude. The effects of climate variability and change in the region since the 1970s have had significant impacts on ecosystems. This paper focuses on analyzing the dynamics of land use land cover in that area. The methodology based on the interpretation of the satellite image for 1972, 1987 and 2016 has led to important results. Thus, there is a notable decline in areas covered by natural plant formations (tiger bush and steppe). Indeed, they range from 28.79% in 1972 to 12.15% in 2016 of the total surface area of the study area. However, farmland increased from 164772 ha in 1972 to 200 697 ha in 2016, an increase of 22%. In addition, the bare spaces which were only 666 ha in 1972 moved to 4189 ha, an increase of more than 500%. Finally, the number of semi-permanent pools rose from 219 to 833 from 1972 to 2016, while the number of Koris increased from 280 to 1573 during the same period, an increase of more than 400%. It seems necessary to take urgent measures to safeguard the ecosystems of the region to allow a more balanced development of the area.

scholarly journals Condicionantes geomorfológicos e da cobertura da terra na ocorrência de movimentos de massa na região serrana do Rio de Janeiro / Geomorphological and cover land conditioning factors of the mass movements in the mountainous region of Rio de Janeiro

2019 ◽  
Vol 29 (56) ◽  
pp. 27 ◽  
Author(s):  
Cristiane Nunes Francisco ◽  
Raquel Conceição Carvalho ◽  
Carla Maciel Salgado
Keyword(s):  
Land Cover ◽  
Rio De Janeiro ◽  
Landscape Evolution ◽  
Southeastern Brazil ◽  
Economic Losses ◽  
Mass Movements ◽  
Mountainous Region ◽  
Conditioning Factors ◽  
Different Types ◽  
Morphological Variables

Movimentos de massa são processos de evolução da paisagem condicionados por fatores geológicos, geomorfológicos, hidrológicos, climáticos e da cobertura vegetal. A região Sudeste do Brasil destaca-se pela ocorrência de eventos catastróficos, pois combina a ocupação das encostas com as características fisiográficas que a deixam altamente suscetível a diferentes tipos de movimentos de massa, destacando-se os escorregamentos translacionais. Embora tenham um importante papel na evolução da paisagem, a ocorrência de movimentos de massa em áreas ocupadas por atividades antrópicas tem gerado inúmeras perdas humanas e prejuízos econômicos. Foi o que ocorreu em janeiro de 2011 na região serrana do Rio de Janeiro, atingida por fortes chuvas que desencadearam eventos de extrema magnitude, e provocaram, além de destruição e morte, marcas profundas (cicatrizes) na paisagem que podem auxiliar no estudo dos processos de movimentos de massa. Este trabalho, assim, tem como objetivo analisar as relações espaciais entre a morfologia das encostas e a cobertura da terra com a ocorrência dos movimentos de massa em janeiro de 2011 na região serrana fluminense. Para tanto, foi realizado um estudo na bacia do rio Roncador, Nova Friburgo (Estado do Rio de Janeiro), com a sobreposição entre o mapeamento das cicatrizes, das variáveis morfológicas das encostas e das classes de cobertura da terra. Os resultados mostram que as cicatrizes predominaram em encostas de forma côncava e íngremes, além de cobertas por vegetação densa, corroborando com a literatura que aponta a declividade e a forma da encosta como fatores condicionantes significativos à ocorrência de movimentos de massa, em especial, dos escorregamentos translacionais.Palavras–chave: escorregamentos translacionais, corridas de lama, sistema de informação geográfica, desastre natural.Abstract Mass movements are landscape evolution processes conditioned by geological, geomorphological, hydrological, climatological and land cover factors. Southeastern Brazil is distinguished by the occurrence of catastrophic landslides events, due to the association of land use and physiographic factors which cause high susceptibility to the occurrence of different types of mass movements, mainly translational slides. Although mass movements have an important role in landscape evolution, their occurrence in areas occupied by human activities has generated numerous life human and economic losses. The mountainous region of Rio de Janeiro, in January 2011, was affected by rainstorms that caused the occurrence of extreme magnitude landslide events, which caused destruction and death as well as deep scars in the landscape, which can contribute to the study of mass movements processes. This paper aims to analyse the spatial relationships between the morphology of the slopes, the land cover and the occurrence of mass movements in January 2011 in the mountainous region of Rio de Janeiro. The study was performed in the Roncador river basin, Nova Friburgo municipality, by overlaying the spatial distribution of landslide scars with morphological variables of the slopes and land cover classes. The results show that the scars predominated on steep and concave slopes covered by dense vegetation, which corroborates the literature that indicates the slope and the curvature as a significant conditioning factor to the occurrence of mass movements, in particular, the translational slides.Keywords: translational slides, mudflows, geographic information system, natural disaster.

D. 41,2,3,21: Titulierte Besitzarten, Erwerbsgründeund das unum genus possidendi

2013 ◽  
Vol 81 (3-4) ◽  
pp. 527-559
Author(s):  
Eric H. Pool
Keyword(s):  
Roman Law ◽  
Negative Effects ◽  
Distinctive Features ◽  
Depth Analysis ◽  
Different Types ◽  
The Law ◽  
The Many

D. 41,2,3,21 turns on the issue of how possessio is to be divided. Understanding its content presupposes making a distinction that was self-evident for the Roman jurist but has never been made by later scholars of Roman law. They do not distinguish the varying ‘causes’ of possession (pro emptore … pro suo) which mark different types of lawful possession, and the ‘causes’ of acquisition (causae adquirendi) which justify obtaining possesion as by an owner. Taking a legally valid sale as an example the distinctive features of (possessio) pro emptore in contrast to emptio are established as well as their relevance for procedural practice. In particular there are no less than six forms of action in the law of inheritance for which these features are relevant. Next, the many negative effects of failing to make this distinction are indicated. There follows an in depth analysis and interpretation of the main phrases in Paul’s text: (i) quod nostrum non est; (ii) causae ad­­quirendi, in particular iustae causae traditionis; (iii) unum genus possidendi; (iv) species infinitae.

Forecasting future changes in Manzala Lake surface area by considering variations in land use and land cover using remote sensing approach

2018 ◽  
Vol 11 (5) ◽  
Author(s):  
Hickmat Hossen ◽  
Mona G. Ibrahim ◽  
Wael Elham Mahmod ◽  
Abdelazim Negm ◽  
Kazuo Nadaoka ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Land Use ◽  
Land Cover ◽  
Surface Area ◽  
Lake Surface ◽  
Lake Surface Area

An Experimental Study on Clay and Sand Mixes to Develop a Non-Linear Homogenized Model for Earth Construction Materials

2022 ◽  
Author(s):  
Elsa Anglade ◽  
Alain Sellier ◽  
Jean-Emmanuel Aubert ◽  
Aurélie Papon
Keyword(s):  
Mechanical Properties ◽  
Experimental Study ◽  
Building Material ◽  
Construction Materials ◽  
Heterogeneous Material ◽  
Single Type ◽  
Model Parameters ◽  
Negative Effects ◽  
Reconstituted Soil ◽  
Clay Matrix

Due to its ecological interest and large availability, a renewed attention is paid to earth as building material. Indeed, raw earth consumes CO2 only during its processing and transportation, and it provides a natural hygrothermal comfort. However, its mechanical properties are highly linked to its composition, which causes an important variability of performances. That is why any soil has to be characterized before being used as a building material. The aim of this study is to propose a model able to predict the hydromechanical behavior of a reconstituted soil according to its composition. As earth is a heterogeneous material, the model is based on homogenization procedures. The sand is considered as spherical inclusions inside a clay matrix. The particularity of the model stands to consider both positive and negative effects of volume variation and mechanical properties of clay under hydric variations. The model parameters are determined according to an original experimental campaign, which is conducted on various mixes of a single type of clay (kaolinite) and of sand, and water. The experimental study provides some mechanical properties of the mixes versus water content and sand content to test the ability of the homogenization model to assess the main properties of this material.

Sign in / Sign up

Export Citation Format

Share Document