scholarly journals Communities and Attachment Networks Associated with Primary, Secondary and Alternative Foundation Species; A Case Study of Stressed and Disturbed Stands of Southern Bull Kelp

Diversity ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 56 ◽  
Author(s):  
Mads S. Thomsen ◽  
Paul M. South
Keyword(s):  
Species Abundance ◽  
Foundation Species ◽  
System Level ◽  
Ecosystem Functions ◽  
Rocky Reefs ◽  
Abundance Patterns ◽  
Control Community ◽  
Ecological Differences

Southern bull kelps (Durvillaea spp., Fucales) are ‘primary’ foundation species that control community structures and ecosystem functions on temperate wave-exposed rocky reefs. However, these large foundation species are threatened by disturbances and stressors, including invasive species, sedimentation and heatwaves. It is unknown whether ‘alternative’ foundation species can replace lost southern bull kelps and its associated communities and networks. We compared community structure (by quantifying abundances of different species) and attachment-interaction networks (by quantifying which species were attached to other species) among plots dominated by Durvillaea spp. and plots where Durvillaea spp. were lost either through long-term repeated experimental removals or by recent stress from a marine heatwave. Long-term experimental removal plots were dominated by ‘alternative’ foundation species, the canopy-forming Cystophora spp. (Fucales), whereas the recent heatwave stressed plots were dominated by the invasive kelp Undaria pinnatifida (Laminariales). A network analysis of attachment interactions showed that communities differed among plots dominated by either Durvillaea spp., Cystophora spp. or U. pinnatifida, with different relationships between the primary, or alternative, foundation species and attached epiphytic ‘secondary’ foundation species. For example, native Cystophora spp. were more important as hosts for secondary foundation species compared to Durvillaea spp. and U. pinnatifida. Instead, Durvillaea spp. facilitated encrusting algae, which in turn provided habitat for gastropods. We conclude that (a) repeated disturbances and strong stressors can reveal ecological differences between primary and alternative foundation species, (b) analyses of abundances and attachment-networks are supplementary methods to identify linkages between primary, alternative and secondary foundation species, and (c) interspersed habitats dominated by different types of foundation species increase system-level biodiversity by supporting different species-abundance patterns and species-attachment networks.

scholarly journals A quantitative review of abundance-based species distribution models

2021 ◽  
Author(s):  
Conor Waldock ◽  
Rick D. Stuart-Smith ◽  
Camille Albouy ◽  
William W. L. Cheung ◽  
Graham J. Edgar ◽  
...  
Keyword(s):  
Species Distribution ◽  
Species Distribution Models ◽  
Species Abundance ◽  
Abundant Species ◽  
Spatial Modelling ◽  
Ecosystem Functions ◽  
Distribution Models ◽  
Abundance Patterns ◽  
Reef Fish Species ◽  
Model Training

The contributions of species to ecosystem functions or services depend not only on their presence in a given community, but also on their local abundance. Progress in predictive spatial modelling has largely focused on species occurrence, rather than abundance. As such, limited guidance exists on the most reliable methods to explain and predict spatial variation in abundance. We analysed the performance of 68 abundance-based species distribution models fitted to 800,000 standardised abundance records for more than 800 terrestrial bird and reef fish species. We found high heterogeneity in performance of abundance-based models. While many models performed poorly, a subset of models consistently reconstructed range-wide abundance patterns. The best predictions were obtained using random forests for frequently encountered and abundant species, and for predictions within the same environmental domain as model calibration. Extending predictions of species abundance outside of the environmental conditions used in model training generated poor predictions. Thus, interpolation of abundances between observations can help improve understanding of spatial abundance patterns, but extrapolated predictions of abundance, e.g. under climate change, have a much greater uncertainty. Our synthesis provides a roadmap for modelling abundance patterns, a key property of species' distributions that underpins theoretical and applied questions in ecology and conservation.

scholarly journals Building the GLENCOE Platform -Grasslands LENding eConomic and ecOsystems sErvices

2021 ◽  
Vol 5 ◽  
Author(s):  
Thais Devincenzi ◽  
Martín Jaurena ◽  
Martín Durante ◽  
Jean Víctor Savian ◽  
Gabriel Ciappesoni ◽  
...  
Keyword(s):  
Grazing Management ◽  
System Level ◽  
Management Systems ◽  
Ecosystem Functions ◽  
Management Actions ◽  
Natural Grasslands ◽  
Grazing Systems ◽  
The Impact ◽  
Livestock Systems

To feed the rising population whilst also preserving ecosystem functions, creative solutions are needed for the ecological intensification of natural grassland-based livestock systems. In Uruguay, natural grasslands are the main nutritional resource for livestock production. In these ecosystems, cattle and sheep graze together all the year round, and grasslands are frequently heavily grazed. Considerable research has been generated concerning grassland management, but there is still no knowledge about the impact of decision rules that supports management actions on long-term ecosystem functioning, at the system level. To meet this deficit, a participatory working group of farmers, researchers, and consultants have developed the GLENCOE platform. This platform is a large-scale facility, supported by INIA-Uruguay, designed to answer the following question: How to intensify the grazing management to improve the sustainability of livestock systems based on natural grasslands? To build the platform three steps were followed: (I) definition of the research problem using a problem tree analysis; (ii) conceptualization of the platform and the design of the grazing systems to be evaluated; and, (iii) spatial allocation of the grazing systems according to the variability of soil, slopes, and seasonal dynamic of vegetation indexes. These criteria were considered across farmlets that were equivalent in the initial stage, allowing causal inferences for the systems trajectories on productive and environmental traits. The platform is composed of three independent farmlets of 50 ha each, where multiparous Hereford cows and Merinos wethers co-graze under three grazing management systems. Each farmlet is managed according to different spatio-temporal decisions of the specific management of vegetation communities, grazing methods, and the stockpile of forage that is allowed by the number of the existing paddocks. Farmlet-1; comprises less decisions (2 paddocks), Farmlet-2; intermediate (8 paddocks), and Farmlet-3; high level of decisions (32 paddocks). This innovative platform will be used as a participatory and interdisciplinary space for research and co-learning of management on processes that can only be observed in long-term evaluations, and at farmlet scale. We expect that this new approach will contribute to the developement and implemention of sustainable grazing management systems in Uruguay.

scholarly journals The importance of isolated patches for maintaining local bird biodiversity and ecosystem function: a case study from the Pernambuco Center of Endemism, Northeast Brazil

2018 ◽  
Vol 108 (0) ◽  
Author(s):  
Leila F. A. S. Campos ◽  
Bruno P. Teixeira ◽  
Márcio A. Efe
Keyword(s):  
Species Abundance ◽  
Bird Species ◽  
Bird Community ◽  
Northeastern Brazil ◽  
Ecosystem Functions ◽  
Forest Fragment ◽  
Human Disturbances ◽  
Highly Sensitive

ABSTRACT The Atlantic Forest has been highly fragmented, with the Pernambuco Center of Endemism (PCE) one of the priority areas for conservation. The Mata do Cedro forest, located in Alagoas state, northeastern Brazil, is a forest fragment within the PCE surrounded by a matrix of sugarcane that acts as a refuge for several threatened bird species, some of which are endemic to the region. Here, we characterize the bird community in Mata do Cedro using measures of species abundance, frequency of occurrence, habitat use and sensitivity to human disturbance. The functional role of species was investigated with a functional dendrogram. We registered 111 species, most resident and forest dependent. The most representative trophic categories were insectivores followed by frugivores. Of the species found, 11 are highly sensitive to human disturbances and 11 are endemic to the PCE. The bird community of the fragment is highly diversified, with endemic taxa and balanced trophic categories typical of preserved tropical forests. This community structure together with the occurrence of threatened species reinforces the importance of Mata do Cedro for the maintenance of local biodiversity and ecosystem functions.

Caregivers' Perceptions of Speech-Language Pathologist Talk About Child Language and Literacy Disorders

2020 ◽  
Vol 29 (4) ◽  
pp. 2049-2067
Author(s):  
Karmen L. Porter ◽  
Janna B. Oetting ◽  
Loretta Pecchioni
Keyword(s):  
Language And Literacy ◽  
Collective Case Study ◽  
Study Approach ◽  
School Aged Children ◽  
Speech Language Pathologist ◽  
Therapy Goals ◽  
Semistructured Interviews ◽  
Types Of Information

Purpose This study examined caregiver perceptions of their child's language and literacy disorder as influenced by communications with their speech-language pathologist. Method The participants were 12 caregivers of 10 school-aged children with language and literacy disorders. Employing qualitative methods, a collective case study approach was utilized in which the caregiver(s) of each child represented one case. The data came from semistructured interviews, codes emerged directly from the caregivers' responses during the interviews, and multiple coding passes using ATLAS.ti software were made until themes were evident. These themes were then further validated by conducting clinical file reviews and follow-up interviews with the caregivers. Results Caregivers' comments focused on the types of information received or not received, as well as the clarity of the information. This included information regarding their child's diagnosis, the long-term consequences of their child's disorder, and the connection between language and reading. Although caregivers were adept at describing their child's difficulties and therapy goals/objectives, their comments indicated that they struggled to understand their child's disorder in a way that was meaningful to them and their child. Conclusions The findings showed the value caregivers place on receiving clear and timely diagnostic information, as well as the complexity associated with caregivers' understanding of language and literacy disorders. The findings are discussed in terms of changes that could be made in clinical practice to better support children with language and literacy disorders and their families.

Evaluating The Effectiveness Of Problem-Based Learning (Pbl) Implemented In The Textile Engineering Course - A Case Study On Ahsanullah University Of Science And Technology, Bangladesh

2014 ◽  
Vol 1 (1) ◽  
pp. 111-114
Author(s):  
Lal Mohan Baral ◽  
Ramzan Muhammad ◽  
Claudiu Vasile Kifor ◽  
Ioan Bondrea
Keyword(s):  
Engineering Students ◽  
Science And Technology ◽  
Problem Based Learning ◽  
Professional Life ◽  
System Level ◽  
Teaching Tool ◽  
Technical Problems ◽  
Empirical Survey ◽  
Undergraduate Programs

AbstractProblem-based learning as a teaching tool is now used globally in many areas of higher education. It provides an opportunity for students to explore technical problems from a system-level perspective and to be self-directed life-long learner which is mandatory for equipping engineering students with the skill and knowledge. This paper presents a case study illustrating the effectiveness of implemented Problem-based learning (PBL) during five semesters in the undergraduate programs of Textile Engineering in Ahsanullah University of Science and Technology (AUST). An assessment has been done on the basis of feedback from the students as well as their employers by conducting an empirical survey for the evaluation of PBL impact to enhance the student's competencies. The Evaluations indicate that students have achieved remarkable competencies through PBL practices which helped them to be competent in their professional life.

Interrelationships between municipal spatial policy strategy and airport operation and development. Lodz Airport case study

2018 ◽  
Vol 59 (1) ◽  
pp. 65-79
Author(s):  
Katarzyna Nikorowicz-Zatorska
Keyword(s):  
Land Use ◽  
Urban Planning ◽  
Cultural Development ◽  
The Other ◽  
Local Authorities ◽  
Spatial Management ◽  
The One ◽  
Surrounding Areas

Abstract The present paper focuses on spatial management regulations in order to carry out investment in the field of airport facilities. The construction, upgrades, and maintenance of airports falls within the area of responsibility of local authorities. This task poses a great challenge in terms of organisation and finances. On the one hand, an active airport is a municipal landmark and drives local economic, social and cultural development, and on the other, the scale of investment often exceeds the capabilities of local authorities. The immediate environment of the airport determines its final use and prosperity. The objective of the paper is to review legislation that affects airports and the surrounding communities. The process of urban planning in Lodz and surrounding areas will be presented as a background to the problem of land use management in the vicinity of the airport. This paper seeks to address the following questions: if and how airports have affected urban planning in Lodz, does the land use around the airport prevent the development of Lodz Airport, and how has the situation changed over the time? It can be assumed that as a result of lack of experience, land resources and size of investments on one hand and legislative dissonance and peculiar practices on the other, aviation infrastructure in Lodz is designed to meet temporary needs and is characterised by achieving short-term goals. Cyclical problems are solved in an intermittent manner and involve all the municipal resources, so there’s little left to secure long-term investments.

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