scholarly journals Using beta diversity to inform agricultural policies and conservation actions on Mediterranean farmland

2017 ◽  
Vol 54 (6) ◽  
pp. 1825-1835 ◽  
Author(s):  
Joana Santana ◽  
Miguel Porto ◽  
Luís Reino ◽  
Francisco Moreira ◽  
Paulo Flores Ribeiro ◽  
...  
2017 ◽  
Author(s):  
Christopher J. Brown ◽  
Richard Hamilton

AbstractEcological communities typically change along gradients of human impact, though it is difficult to estimate the footprint of impacts for diffuse threats like pollution. Here we develop a joint model of benthic habitats on lagoonal coral reefs and use it to infer change in benthic composition along a gradient of distance from logging operations. The model estimates both changes in abundances of benthic groups and their compositional turn-over, a type of beta-diversity. We detect compositional turnover across the gradient and use the model to predict the footprint of turbidity impacts from logging. We then apply the model to predict impacts of recent logging activities, finding recent impacts to be small, because recent logging has occurred far from lagoonal reefs. Our model can be used more generally to estimate the footprint of human impacts on ecosystems and evaluate the benefits of conservation actions for ecosystems.


Author(s):  
E Martins Camara ◽  
Tubino Andrade Andrade-Tub ◽  
T Pontes Franco ◽  
LN dos Santos ◽  
AFGN dos Santos ◽  
...  

2014 ◽  
Vol 25 (3-4) ◽  
pp. 53-68
Author(s):  
I. V. Goncharenko ◽  
H. M. Holyk

Cenotic diversity and leading ecological factors of its floristic differentiation were studied on an example of two areas – Kyiv parks "Nivki" and "Teremki". It is shown that in megalopolis the Galeobdoloni-Carpinetum impatientosum parviflorae subassociation is formed under anthropogenic pressure on the typical ecotope of near-Dnieper hornbeam oak forests on fresh gray-forest soils. The degree of anthropogenic transformation of cenofloras can be estimated by the number of species of Robinietea and Galio-Urticetea classes, as well as neophytes and cultivars. Phytoindication for hemeroby index may be also used in calculation. We propose the modified index of biotic dispersion (normalized by alpha-diversity) for the estimation of ecophytocenotic range (beta-diversity) of releves series. We found that alpha-diversity initially increases (due to the invasion of antropophytes) at low level of antropogenic pressure, then it decreases (due to the loss of aboriginal species) secondarily with increasing of human impact. Also we found that beta-diversity (differential diversity) decreases, increasing homogeneity of plant cover, under the influence of anthropogenic factor. Vegetation classification was completed by a new original method of cluster analysis, designated as DRSA («distance-ranked sorting assembling»). The classification quality is suggested to be validated on the "seriation" diagram, which is а distance matrix between objects with gradient filling. Dark diagonal blocks confirm clusters’ density (intracluster compactness), uncolored off-diagonal blocks are evidence in favor of clusters’ isolation (intercluster distinctness). In addition, distinction of clusters (syntaxa) in ordination area suggests their independence. For phytoindication we propose to include only species with more than 10% constancy. Furthermore, for the description of syntaxonomic amplitude we suggest to use 25%-75% interquartile scope instead of mean and standard deviation. It is shown that comparative analysis of syntaxa for each ecofactor is convenient to carry out by using violin (bulb) plots. A new approach to the phytoindication of syntaxa, designated as R-phytoindication, was proposed for our study. In this case, the ecofactor values, calculated for individual releves, are not taken into account, however, the composition of cenoflora with species constancies is used that helps us to minimize for phytoindication the influence of non-typical species. We suggested a syntaxon’s amplitude to be described by more robust statistics: for the optimum of amplitude (central tendency) – by a median (instead of arithmetic mean), and for the range of tolerance – by an interquartile scope (instead of standard deviation). We assesses amplitudes of syntaxa by phytoindication method for moisture (Hd), acidity (Rc), soil nitrogen content (Nt), wetting variability (vHd), light regime (Lc), salt regime (Sl). We revealed no significant differences on these ecofactors among ecotopes of our syntaxa, that proved the variant syntaxonomic rank for all syntaxa. We found that the core of species composition of our phytocenoses consists of plants with moderate requirements for moisture, soil nitrogen, light and salt regime. We prove that the leading factor of syntaxonomic differentiation is hidden anthropogenic, which is not subject to direct measurement. But we detect that hidden factor of "human pressure" was correlated with phytoindication parameters (variables) that can be measured "directly" by species composition of plant communities. The most correlated factors were ecofactors of soil nitrogen, wetting variability, light regime and hemeroby. The last one is the most indicative empirically for the assessment of "human impact". We establish that there is a concept of «hemeroby of phytocenosis» (tolerance to human impact), which can be calculated approximately as the mean or the median of hemeroby scores of individual species which are present in it.


Author(s):  
Leen Adeeb Fakhoury ◽  
Naif Adel Haddad

This paper attempts to present and discuss the outcome of the results of the key different studies and projects carried out at Salt and at Irbid historic cores.  It focuses on the executed urban heritage projects undertaken mainly by the Ministry of Tourism and Antiquities (MoTA) of Jordan in the last two decades. It discusses their different aspects through initial assessment of the loss and degradation of the cultural heritage assets of the two cities; the fragmentation and lack of connectivity between the modern and historic cores; issues of sustainability of architectural and urban heritage projects i.e. tourism planning and conservation; and reuse projects at the historic cores in relation to cultural, physical factors and development needs. It also addresses the behaviour and characteristics of the urban regeneration process in those two historic cities, starting from their documentation to examination of the different aspects of the currently adopted urban practices and policies, and their impact on the existing urban heritage, depending on the specific identity of the respective historic cores. Finally, it aims to define the main constraints and challenges for the reuse of the existing heritage fabric including the local community quality of life, while building on sustainable heritage activities accommodating tourism opportunities. This will give, at least, some indications from which we can identify a use or combination of uses, and practical steps needed for successful heritage conservation actions in Jordan, in order to retain the cultural significance of the place.


2019 ◽  
Vol 21 (2) ◽  
pp. 205-217
Author(s):  
Nádson Ricardo Leite de Souza ◽  
Vanessa Vasconcelos da Silva ◽  
Edson Henrique Almeida de Andrade ◽  
Valéria Raquel Porto de Lima

A Mata do Buraquinho consiste no maior remanescente de Mata Atlântica em área urbana do país, é cortada pelo Rio Jaguaribe, um dos afluentes do Rio Paraíba e maior rio urbano de João Pessoa/PB que, represado, forma o Açude do Buraquinho, de onde provém parte da água potável da capital paraibana. O local é declarado uma Área de Preservação Permanente desde 1989, devido à importância ambiental e, desde o ano de 2000, abriga o Jardim Botânico Benjamin Maranhão, que ocupa mais de 65% da área total, criado com a missão de fortalecer as ações de preservação e promover a intensificação dos estudos no representativo ambiente, todavia, a existência de trilhas em seu interior possibilita maior vulnerabilidade à degeneração ecossistêmica, somada aos efeitos de borda no contato com a densa urbanização do entorno. Com o objetivo de analisar os impactos ambientais negativos ocasionados por tais bordas, foram realizadas observações in loco, por meio de inventariações de parcelas concretizadas ao longo das trilhas mais frequentadas, onde se apurou diversos indicativos de degradação florestal. A partir disso, confirmou-se a autenticidade das teorias empregadas sobre os impactos ambientais negativos e a degeneração das espécies habituais, resultantes das ações de caráter antrópico, concluindo-se que a propagação dos efeitos de borda originada pela abertura de trilhas que favorecem o avanço da degradação e fazem-se necessárias ações de conservação mais rigorosas do que as em vigor, mesmo se tratando de uma área legalmente protegida.Palavras-chave: Efeitos de borda; Degeneração ecossistêmica; Mata do Buraquinho. ABSTRACTMata do Buraquinho is the largest remnant of Mata Atlântica in an urban area of the country. It is cut by the Jaguaribe River, - one of the tributaries of the Paraíba River and the largest urban river of João Pessoa/PB – which was dammed up forming the Açude do Buraquinho, from where comes part of the potable water of the capital of Paraíba. The place has been declared a Permanent Preservation Area since 1989. Due to its environmental importance and, since the year of 2000, it has sheltered the Benjamin Maranhão Botanical Garden, which occupies more than 65% of the total area. This garden was created with the mission of strengthening actions of preservation and to promote the intensification of studies in the representative environment. However, the existence of trails inside of it, allows greater vulnerability to the ecosystem degeneration, and combined with effects of border in the contact with the dense urbanization of the surrounding area. In order to analyze the negative environmental impacts caused by such edges, some observations were made in loco, through inventories of concretized plots along the most frequented trails, where several indications of forest degradation were obtained. From this, the authenticity of the theories used on the negative environmental impacts and the degeneration of the habitual species was confirmed. And resulting from actions of anthropic character, it was concluded that the propagation of the edge effects originated by the opening of tracks, favors the advance of the degradation and becomes necessary conservation actions more stringent than those in force, even in the case of a legally protected area. Keywords: Edge effects; Ecosystem Degeneration; Mata do Buraquinho. RESUMENLa “Mata do Buraquinho” es el testimonio más grande del bosque Atlántico en el área urbana de Brasil, es cortado por el Río Jaguaribe, uno de los tributarios del Río Paraíba, además, es el río urbano más grande de João Pessoa/PB, que forma la presa del “Buraquinho”, de donde proviene el suministro de agua potable para la capital del Estado de Paraíba. Esta zona es declarada un Área de Preservación Permanente desde 1989, debido a su importancia ambiental, y desde el año 2000, acoge el Jardín Botánico Benjamin Maranhão, que ocupa más de 65% del área total, creado con la misión de fortalecer las acciones de preservación y promover la intensificación de los estudios en el representativo de ambiente, sin embargo, la existencia de rutas en el interior aumenta la vulnerabilidad a la degeneración ecosistémica, añadidos a los efectos de borde que tienen contacto directo con la densa urbanización de los alrededores. Con el propósito de analizar los impactos ambientales negativos ocasionados por estos bordes, han sido realizadas observaciones "In loco", a través de inventariaciones de parcelas implementadas a lo largo de las rutas más frecuentadas, donde se ha detectado indicios de degradación forestal. Con eso, se ha confirmado la autenticidad de las teorías utilizadas sobre los impactos ambientales negativos y la degeneración de especies habituales, resultantes de acciones antrópicas, se concluye que la propagación de los efectos de borde originada por la apertura de rutas ha favorecido el avance de la degradación, con eso, son necesarias acciones de conservación todavía más estrictas de que las que existen, aún que ya sea un área protegida por la ley.Palabras-clave: Efectos de borde; Degeneración ecosistémica; Mata do Buraquinho.


2010 ◽  
Vol 18 (4) ◽  
pp. 323 ◽  
Author(s):  
Chen Shengbin ◽  
Ouyang Zhiyun ◽  
Xu Weihua ◽  
Xiao Yi

2011 ◽  
Author(s):  
J. M. Scott ◽  
Edward O. Garton ◽  
Brian Dennis ◽  
Jon S. Horne ◽  
Dale Goble ◽  
...  

2014 ◽  
Author(s):  
Vasily Yakimovich Uzun ◽  
Valery A. Saraykin ◽  
Natalia Karlova ◽  
Ekaterina Gataulinn

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