Relevant bibliographies by topics / Anthropogenic disturbances

Academic literature on the topic 'Anthropogenic disturbances'

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Published: 4 June 2021
Last updated: 20 February 2023

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Journal articles on the topic "Anthropogenic disturbances"

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McConkey, Kim. "Anthropogenic Disturbances." Resonance 25, no. 5 (May 2020): 677–89. http://dx.doi.org/10.1007/s12045-020-0983-1.

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Lugo, Ariel E. "Effects of Extreme Disturbance Events: From Ecesis to Social–Ecological–Technological Systems." Ecosystems 23, no. 8 (February 18, 2020): 1726–47. http://dx.doi.org/10.1007/s10021-020-00491-x.

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AbstractEcologists addressed the effects of disturbances from the onset of the field by focusing on ecesis, which is the process by which organisms migrate and establish under the environmental conditions created by disturbances. Ecesis is the onset of succession, a self-organizing process whose nature, speed, and outcome depend in part on the outcomes of ecesis and the residual legacies remaining after disturbances. A by-product of succession after a disturbance is the reorganization of species dominance, or novelty. The degree of novelty in the outcome increases with the severity of the disturbance event. Initially, ecologists focused mostly on non-anthropogenic disturbances, but as human activity intensified and became a global force, more attention was given to the effects of anthropogenic disturbances on ecosystems. Today, anthropogenic and non-anthropogenic disturbances and their interactions are increasingly affecting ecosystems, particularly those exposed to extreme disturbance events. Extreme disturbance events are complex and low probability events composed of several disturbance forces that individually and in synergy affect different sectors of ecosystems, including the conditions that drive ecesis. I review the literature on disturbance research including the effects of extreme disturbance events on social–ecological–technological systems (SETSs). A SETS is an ecosystem defined by the flow and accumulation of energy through the medium of organisms, constructed infrastructure, institutions, and their environment. Human intentions, values, and capacities are part of the functioning of SETS, and they can drive ecological processes as do non-anthropogenic forces. Moreover, human-directed activities after an extreme disturbance event affect whole landscapes. The passage of hurricane María over the Puerto Rico SETS established that extreme disturbance events are of such power and complexity that they can influence the level and kind of relationship between humans and the environment, including the structure and species composition of the ecological systems within SETS. However, extreme disturbance events such as hurricanes have not changed the successional trajectory originally impulsed by anthropogenic disturbances. Thus, the species composition and functioning of novel forests in Puerto Rico are tied to economic activity in the social and technological sectors of SETS. It is no longer possible to interpret ecosystem functioning without considering the synergy between anthropogenic and non-anthropogenic extreme disturbances.
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Liu, Xiaolong, Zhengtao Shi, Guangcai Huang, Yanchen Bo, and Guangjie Chen. "Time Series Remote Sensing Data-Based Identification of the Dominant Factor for Inland Lake Surface Area Change: Anthropogenic Activities or Natural Events?" Remote Sensing 12, no. 4 (February 12, 2020): 612. http://dx.doi.org/10.3390/rs12040612.

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Inland lake variations are considered sensitive indicators of global climate change. However, human activity is playing as a more and more important role in inland lake area variations. Therefore, it is critical to identify whether anthropogenic activity or natural events is the dominant factor in inland lake surface area change. In this study, we proposed a method that combines the Douglas-Peucker simplification algorithm and the bend simplification algorithm to locate major lake surface area disturbances. These disturbances were used to extract the features that been used to classify disturbances into anthropogenic or natural. We took the nine lakes in Yunnan Province as test sites, a 31-year long (from 1987 to 2017) time series Landsat TM/OLI images and HJ-1A/1B used as data sources, the official records were used as references to aid the feature extraction and disturbance identification accuracy assessment. Results of our method for disturbance location and disturbance identification could be concluded as follows: (1) The method can accurately locate the main lake changing events based on the time series lake surface area curve. The accuracy of this model for segmenting the time series of lake surface area in our study area was 94.73%. (2) Our proposed method achieved an overall accuracy of 87.75%, with an F-score of 85.71 for anthropogenic disturbances and an F-score of 88.89 for natural disturbances. (3) According to our results, lakes in Yunnan Province of China have undergone intensive disturbances. Human-induced disturbances occurred almost twice as much as natural disturbances, indicating intensified disturbances caused by human activities. This inland lake area disturbance identification method is expected to uncover whether a disturbance to inland lake area is human activity-induced or a natural event, and to monitor whether disturbances of lake surface area are intensified for a region.
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Bisson, Isabelle-Anne, Luke K. Butler, Tim J. Hayden, L. Michael Romero, and Martin C. Wikelski. "No energetic cost of anthropogenic disturbance in a songbird." Proceedings of the Royal Society B: Biological Sciences 276, no. 1658 (December 2, 2008): 961–69. http://dx.doi.org/10.1098/rspb.2008.1277.

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Anthropogenic or natural disturbances can have a significant impact on wild animals. Therefore, understanding when, how and what type of human and natural events disturb animals is a central problem in wildlife conservation. However, it can be difficult to identify which particular environmental stressor affects an individual most. We use heart rate telemetry to quantify the energy expenditure associated with different types of human-mediated and natural disturbances in a breeding passerine, the white-eyed vireo ( Vireo griseus ). We fitted 0.5 g heart rate transmitters to 14 male vireos and continuously recorded heart rate and activity for two days and three nights on a military installation. We calibrated heart rate to energy expenditure for five additional males using an open-flow, push-through respirometry system showing that heart rate predicted 74 per cent of energy expenditure. We conducted standardized disturbance trials in the field to experimentally simulate a natural stressor (predator presence) and two anthropogenic stressors. Although birds initially showed behavioural and heart rate reactions to some disturbances, we could not detect an overall increase in energy expenditure during 1- or 4-hours disturbances. Similarly, overall activity rates were unaltered between control and experimental periods, and birds continued to perform parental duties despite the experimental disturbances. We suggest that vireos quickly determined that disturbances were non-threatening and thus showed no (costly) physiological response. We hypothesize that the lack of a significant response to disturbance in vireos is adaptive and may be representative of animals with fast life histories (e.g. short lifespan, high reproductive output) so as to maximize energy allocation to reproduction. Conversely, we predict that energetic cost of human-mediated disturbances will be significant in slow-living animals.
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Ezcurra, Exequiel. "Anthropogenic disturbances infiltrate forest fragments." Proceedings of the National Academy of Sciences 113, no. 19 (April 29, 2016): 5150–52. http://dx.doi.org/10.1073/pnas.1604829113.

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Ji, Li, Yuan Li, Guixiang Zhang, and Yonghong Bi. "Anthropogenic Disturbances Have Contributed to Degradation of River Water Quality in Arid Areas." Water 13, no. 22 (November 22, 2021): 3305. http://dx.doi.org/10.3390/w13223305.

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The earth has been reshaped for millennia. The accelerating pace of anthropogenic activities has generated enormous impacts on the water environment. As one of the main drivers of landscape change, anthropogenic disturbance has brought many negative effects on rivers. Studying the relationship between anthropogenic disturbances and river water quality is of significance for regional conservation and ecosystem management, while the relationship remains poorly understood in the current. In this study, we quantified anthropogenic disturbances by introducing the concept of the hemeroby index and evaluated rivers’ water quality in eight sub-watersheds on the Loess Plateau. The results indicated that 37.5% of the sub-watersheds were in Eutrophic status, and 62.5% were in Marginal water quality index. The river water quality was most poor in the southwestern region near the Yellow River with high-level anthropogenic disturbance. A correlation analysis between water quality indicators and hemeroby suggested that anthropogenic disturbance contributed to a significant water quality deterioration trend (p < 0.01). The river water quality was relatively sensitive to the changes of completely disturbed land-use covers, including urban and industrial land. Our findings provide theoretical guidance for regional water resources conservation and ecosystem management in arid areas.
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H. Punia, H. Dhiman, H. Saharan, and S. Jakhar. "Floristic Composition and Diversity in Response to Varying Degrees of Disturbance in Tropical Dry Deciduous Forests of Southern Haryana, India." Ecology, Environment and Conservation 28, no. 04 (2022): 2164–73. http://dx.doi.org/10.53550/eec.2022.v28i04.079.

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The aim of the current investigation was to study the effects of anthropogenic disturbances on the vegetation structure of the three Tropical Dry Deciduous Forests of Southern Haryana i.e., Mandhana, Ghasola, and Mandhiali in the Bhiwani, Charkhi Dadri, and Mahendergarh districts, respectively. The data were collected from March, 2020 to March, 2021. The floristic composition was quantified by randomly placing 15 quadrats per site (45 in total). A disturbance index was developed for each site and high, medium and low disturbance areas were identified based on prevailing disturbances that were found to be maximum for Mandhiali (21), followed by Ghasola (16) and Mandhana (9). Ecological parameters such as frequency, density, abundance, basal area, IVI, and diversity indices were calculated for each siteduring the study. A total of 50 species of plants representing 44 genera and 25 families were observed consisting of 14 trees, 9 shrubs, and 27 herbs during the investigation of floristic composition. The species richness decreased with an increase in the disturbance level on the three sites viz., Mandhana (40), Ghasola (33), and Mandhiali (29) respectively. The value of Shannon Weiner diversity index (H’) and Pielou Index of evenness (E) declined with an increasing disturbance while Simpson index of dominance (Cd) increased as the disturbance levels increased across the three sites. The results offer significant evidence that anthropogenic disturbances in arid regions of South Haryana play a vital role in community structure and composition. In a forest ecosystem, anthropogenic disturbances cause habitat fragmentation along with soil erosion, loss of soil fertility and biodiversity, etc. The selected forests are in urgent need of management activities to check the intensity of disturbances by controlling anthropogenic pressure on these ecosystems and save them from further degradation. Thus, the present study intensifies the need for phytosociological studies crucial for proper management and conservation purposes.
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Bednařík, J., V. Čada, and K. Matějka. "Forest succession after a major anthropogenic disturbance: a case study of the Jewish Forest in the Bohemian Forest, Czech Republic." Journal of Forest Science 60, No. 8 (September 1, 2014): 336–48. http://dx.doi.org/10.17221/57/2014-jfs.

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The knowledge of forest development after disturbances, particularly anthropogenic disturbances, is of major importance for forest management. Many areas of mountain forests in Europe have been affected by human activities such as felling and livestock grazing in the past and then left for natural succession. Those forests provide several ecosystem services (e.g. soil or avalanche protection) and therefore it is vital to know their developmental processes. The Norway spruce forest stand in the area of Medvěd&iacute; Mt. (&Scaron;umava National Park, Czech Republic), known as the Jewish Forest, is considered an example of succession after anthropogenic disturbances. This study aimed to: <br /> (1) analyse the history of disturbances which affected the locality, (2) describe the subsequent process of forest succession which led to the development of the present forest formation. We conducted a dendrochronological analysis and a spatial analysis. The main cohort was established after a period of disturbances in the first half of the 20<sup>th</sup> century. Both natural (windstorm) and anthropogenic (logging and livestock grazing) disturbances coincided during this period. Regeneration of low density was restricted to a short period after the disturbance and was likely dependent on the occurrence of proper microsites. Later, regeneration was probably obstructed by lack of convenient microsites and high competition of the herb layer. Nowadays, new regeneration emerges together with proper microsite at decaying wood and near mature trees. We conclude that anthropogenic disturbances can limit the density and heterogeneity of regeneration, which leads to the establishment of sparse stand. This structure can persist for decades before proper microsites accumulate and enable regeneration. &nbsp;
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Bradley, Elizabeth A., and Graeme Lockaby. "Invasive Wild Pigs: A Significant Disturbance in Coastal Forests." Forests 12, no. 8 (August 5, 2021): 1042. http://dx.doi.org/10.3390/f12081042.

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Introduced in ~59 countries and native across Europe and Asia, wild pigs, Sus scrofa, are the most wide-spread swine species in the world. As ecosystem engineers, wild pigs are a significant source of disturbance in introduced ecosystems due to their numerous, complex impacts on ecosystem processes. Wild pigs are often found in the resource-rich habitat of coastal forests. Coastal forests are complex, dynamic systems with tremendous biodiversity. Exposed to recurrent disturbances, the biophysical characteristics of coastal forests contribute to their ability to return to their original state post-disturbance. However, compounding disturbances can weaken this ability and threaten the health and function of the ecosystem. In this review, through the model of the forests of the southeastern United States Coastal Plain, we (1) describe conditions found across the forested coastal landscape, (2) describe wild pig disturbance, and (3) discuss how wild pig impacts can add to significant anthropogenic and climate-related disturbances threatening coastal forests. Through this review, we find that the impacts of wild pig disturbance on coastal forests often have similar effects as anthropogenic and climate change-related disturbances that may enhance these significant threats to coastal forest function and resiliency.
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Roberts, Mark R. "Response of the herbaceous layer to natural disturbance in North American forests." Canadian Journal of Botany 82, no. 9 (September 1, 2004): 1273–83. http://dx.doi.org/10.1139/b04-091.

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Most work on the disturbance ecology of North American forests has focused on the tree canopy and woody understory, with little consideration of the herbaceous layer. Understanding how this species-rich and ecologically important layer responds to natural disturbances is needed as a guide for conservation. As a framework for this review, selected natural disturbances common to North American forests are evaluated in terms of a three-axis model of disturbance severity: percentage of tree canopy removed, percentage of understory vegetation removed, and percentage of forest floor and soil removed or disrupted. Eight factors, which control herbaceous-layer response, are linked to the three axes; these factors vary in dominance, depending on disturbance type and severity. The relative importances of different species' regeneration mechanisms also vary along severity gradients. The disturbance-severity model, along with the linked response factors and regeneration mechanisms, provide a framework for evaluating impacts of both natural and anthropogenic disturbances. Long-term studies of herbaceous-layer response to disturbance are needed, particularly mechanistic studies that focus on the relative importance of the eight factors controlling response. The conceptual model proposed herein needs to be tested across the full spectrum of severity levels. Finally, comparisons between natural and anthropogenic disturbances are needed.Key words: disturbance, forests, herbaceous layer, life-history characteristics, succession, understory.
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Dissertations / Theses on the topic "Anthropogenic disturbances"

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Eklöf, Johan S. "Anthropogenic Disturbances and Shifts in Tropical Seagrass Ecosystems." Doctoral thesis, Stockholm University, Department of Systems Ecology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-7285.

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Seagrasses constitute the basis for diverse and productive ecosystems worldwide. In East Africa, they provide important ecosystem services (e.g. fisheries) but are potentially threatened by increasing resource use and lack of enforced management regulations. The major aim of this PhD thesis was to investigate effects of anthropogenic distur-bances, primarily seaweed farming and coastal fishery, in East African seagrass beds. Seaweed farming, often depicted as a sustainable form of aquaculture, had short- and long-term effects on seagrass growth and abundance that cascaded up through the food web to the level of fishery catches. The coastal fishery, a major subsistence activity in the region, can by removing urchin predators indirectly increase densities of the sea urchin Tripneustes gratilla, which has overgrazed seagrasses in several areas. A study using simulated grazing showed that high magnitude leaf removal – typical of grazing urchins – affected seagrasses more than low magnitude removal, typical of fish grazing. Different responses in two co-occurring seagrass species furthermore indicate that high seagrass diversity in tropical seagrass beds could buffer overgrazing effects in the long run. Finally, a literature synthesis suggests that anthropogenic disturbances could drive shifts in seagrass ecosystems to an array of alternative regimes dominated by other or-ganisms (macroalgae, bivalves, burrowing shrimp, polychaetes, etc.). The formation of novel feedback mechanisms makes these regimes resilient to disturbances like seagrass recovery and transplantation projects. Overall, this suggests that resource use activities linked to seagrasses can have large-scale implications if the scale exceeds critical levels. This emphasizes the need for holistic and adaptive management at the seascape level, specifically involving improved techniques for seaweed farming and fisheries, protection of keystone species, and ecosystem-based management approaches.

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Eklöf, Johan S. "Anthropogenic disturbances and shifts in tropical seagrass ecosystems /." Stockholm : Department of Systems Ecology, Stockholm University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-7285.

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PAPAZACHARIOU, VASILIKI. "Coral Fungia fungites- associated microbial communities and their shifts upon anthropogenic disturbances." Thesis, Uppsala universitet, Limnologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-377137.

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One of the main focus of coral reef ecology has been to shed light on the importance of all microbial members of coral holobiont and how their interactions contribute to the coral’s resilience. However, knowledge is lacking about the composition of microbial communities inhabiting the surface mucus layer of corals including Fungia fungites, a species that lives under stressful conditions close to fish farms in Vietnam. I investigated the prokaryotic communities that are thriving in Fungia fungites surface mucus layer (SML) in the wild and how they were affected upon antibiotics and nitrogen stress using 16S rRNA gene-based techniques. Firstly, I observed a significant alteration in the composition of microbial communities due to antibiotics effect, with exposed communities featuring lower richness and α-diversity in contrast to the controls. Further, mucosal microbial communities were found to be mostly dominated by Proteobacteria (especially of the classes of Alphaproteobacteria and Gammaproteobacteria) and less by Bacteroidetes (Flavobacteriia). Results from this study suggest a developed antibiotic resistance of Alteromonadales and Campylobacterales indicated by their increased abundance upon antibiotics effect. Moving forward, future studies should focus on exploring also the contribution of non-prokaryotic microbial members of Fungia fungites holobiont and how antibiotic resistance can potentially influence coral’s health. The results support that Fungia fungites SML microbial communities are strongly affected by antibiotics exposure and call for future research to focus on the function of these microbial communities and how they can contribute to the coral’s resilience.
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Abdelnour, Alex Gabriel. "Assessing ecosystem response to natural and anthropogenic disturbances using an eco-hydrological model." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42899.

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The impact of natural and anthropogenic disturbances on catchment hydrological and biogeochemical dynamics are difficult or impossible to capture through experimentation or observation alone. Process-based simulation models can address this need by providing a framework for synthesizing data describing catchment responses to climate, harvest, fire, and other disturbances. However, existing models are either too simple to capture important process-level hydrological and biogeochemical controls on ecosystem responses to disturbance, or are too computationally expensive to simulate the local dynamics over large watershed areas, or require a high level of expertise to implement. To this end, a spatially distributed, physically based, eco-hydrological model (VELMA: Visualizing Ecosystems for Land Management Assessments) that is both computationally efficient and relatively easy to implement is developed. VELMA is a state-of-the-art model with real-time visualization tools that shows temporal and spatial patterns of state and flux variables, and is used to address the effects of changes in climate, land-use, and other interacting stressors on multiple ecosystem services such as timber production, carbon sequestration, regulation of water quality and quantity and reduction of greenhouse gases at scales relevant to formulating management decisions. In this study, VELMA was applied to the H.J. Andrews Experimental forest, an intensively studied watershed with observed daily temperature, precipitation, streamflow, and nutrient losses data. VELMA was first used to explore the factors that controls catchment response to forest harvest. Specifically, elucidate how forest harvest factors such as harvest location and amount control watershed hydrological and biogeochemical fluxes. Thereafter, VELMA was used to reconstruct and analyze the impact of two significant disturbance events − a stand replacing fire and a 100% clearcut − on vegetation and soil carbon and nitrogen dynamics. Finally, VELMA was used to explore the potential impact of climate change on catchment hydrological regime, site productivity and carbon and nitrogen dynamics at high spatial resolution relevant to formulating management decision. The main insights from this study include: (1) streamflow, nutrient losses to the stream, and gaseous carbon and nitrogen losses to the atmosphere are strongly sensitive to the location of harvest as a result of the spatial variation in soil water content, plant nitrogen uptake, soil organic carbon decomposition, nitrification, and denitrification within the watershed, (2) forested riparian buffers reduce water and nutrient losses to the stream through plant transpiration, plant nitrogen uptake, soil storage, and soil microbial decomposition, (3) following fire and harvest, losses of N from the terrestrial system to the stream are tightly constrained by the hydrological cycle and driven mainly by wet-season rain events large enough to generate hydrologic connectivity and flushing of nutrients along hillslopes, (4) climate change strongly impacts the hydrological regime in the Pacific Northwest as a result of less snowpack, earlier snowmelt, higher winter streamflow, lower summer streamflow, and soil moisture deficit, and (5) climate change increases plant and soil biomass accumulation as a result of longer growing season and higher soil organic decomposition, reduce water quality by increasing the amount of nutrients that reach the stream, and transforms the ecosystem into a net source of carbon to the atmosphere.
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Neigh, Christopher Sean R. "Identifying and understanding North American carbon cycle perturbations from natural and anthropogenic disturbances." College Park, Md.: University of Maryland, 2008. http://hdl.handle.net/1903/8172.

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Thesis (Ph. D.) -- University of Maryland, College Park, 2008.
Thesis research directed by: Dept. of Geography. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Chandrasekara, W. U. "The effects of anthropogenic disturbances on the macrobenthic fauna of saltmarshes and their recovery." Thesis, University of Newcastle Upon Tyne, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320394.

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Tolkkinen, M. (Mikko). "Biodiversity and ecosystem functioning in boreal streams:the effects of anthropogenic disturbances and naturally stressful environments." Doctoral thesis, Oulun yliopisto, 2015. http://urn.fi/urn:isbn:9789526209043.

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Abstract The effect of biodiversity loss and change on the functioning of ecosystems is one of the key questions in ecological research. For stream ecosystems, compelling evidence indicates that species diversity may enhance ecosystem functions. However, ecosystem functions are often regulated by the same environmental factors that also shape diversity; thus, a major challenge for ecologists is to separate the effects of biodiversity loss on the ecosystem functions from the direct effects of human induced disturbance. In this doctoral thesis, I studied how decomposer communities and ecosystem functions respond to human disturbances (nutrient enrichment, acidification) and a natural stressor (naturally low water pH). I also studied how human disturbances and natural stressors affect the phylogenetic structure of stream fungal communities. I showed that human disturbance had a strong impact on species dominance patterns by reducing species evenness. Species dominance patterns also explained the variation in decomposition rates. Changes in abiotic variables also had a direct effect on leaf decomposition rates. In the naturally acidic sites, human impact (land drainage) further decreased water pH and increased metal concentrations, thereby reducing leaf decomposition rates, whereas high nutrient concentrations enhanced leaf decomposition. Naturally low pH had no effect on decomposition rates. Decomposer community similarity was higher in drainage-impacted sites, but only in naturally acidic, not in circumneutral, streams. Human induced disturbance also modified the phylogenetic similarity of fungal decomposer communities, with communities in disturbed sites consisting of more closely related species when compared to those in circumneutral reference sites. Leaf litter decomposition showed greater temporal variation in human disturbed sites than in reference sites, whereas fungal community variability was similar in disturbed and reference sites. Thus, temporally replicated monitoring may be needed for a reliable assessment of human disturbance in streams. My thesis emphasizes that using both functional and taxonomic measures allows a more comprehensive assessment of biological responses to human disturbance
Tiivistelmä Biodiversiteetin väheneminen ja siitä seuraava ekosysteemin toiminnan heikkeneminen on eräs keskeisimmistä ekologisista kysymyksistä. Ekosysteemin toiminnot ovat kuitenkin monesti yhteydessä ympäristöolosuhteisiin, joten on vaikea erottaa vähentyneen biodiversiteetin ja ympäristöolojen suhteellista merkitystä ekosysteemien toimintoihin. Tässä väitöskirjatyössäni tutkin, kuinka virtavesien hajottajayhteisöt ja ekosysteemin toiminnot (lehtikarikkeen hajotus) muuttuvat valuma-alueen ihmistoimintojen myötä. Tutkin myös, kuinka luontainen stressi (matala pH) vaikuttaa yhteisöihin ja ekosysteemin toimintoihin. Tarkastelen myös akvaattisten sienten fylogeneettistä rakennetta ihmistoiminnan muuttamissa vesiympäristöissä. Osoitan tutkimuksissani, että ihmistoiminnoilla on vaikutuksia hajottajayhteisöiden kokonaisrunsauden jakautumiseen lajien kesken. Muutamien runsaiden lajien dominoimissa yhteisöissä lehtikarikkeen hajoaminen on tehokkaampaa kuin yhteisöissä, joissa lajien runsauserot ovat pienempiä. Myös ympäristöoloilla on vaikutus lehtikarikkeen hajotukseen. Luontaisesti happamissa puroissa metsäojituksen seurauksena lisääntynyt veden metallipitoisuus ja alhainen pH vähentävät hajotuksen määrää. Toisaalta joen korkea ravinnepitoisuus lisää hajotusta. Lehtikarikkeen hajotus vaihtelee enemmän vuosien välillä ihmistoimintojen muuttamissa virtavesissä kuin luonnontilaisissa vesissä. Toisaalta sieniyhteisöt pysyvät koostumukseltaan samankaltaisina vuosien välillä ihmistoiminnan muuttamissa paikoissa ja referenssipaikoissa. Tämä työ osoittaa, että toiminnallisten ja yhteisöihin perustuvien indikaattorien yhteiskäyttö antaa kokonaisvaltaisimman kuvan ihmistoimintojen vaikutuksesta virtavesien ekosysteemeihin
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Grubh, Archis R. "Effects of anthropogenic disturbances and biotic interactions on stream biota in gulf coastal plain streams." The Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=osu1155753270.

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Pellecchia, Antonella. "Experimental analysis of the effects of extreme events of mechanical disturbance on rocky shore algal and invertebrate assemblages in the Bagnoli-Coroglio post-industrial area and in reference sites in the Gulf of Naples." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/17977/.

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Among the various natural and anthropogenic threats to coastal systems, industrial activities and their heritage of local contamination play a key role, especially where new disturbances are superimposed to extant degraded conditions. This may affect the functioning of assemblages, including their ability to recover, in unpredictable ways. Organisms subject to chronic contamination may respond better to a present discrete disturbance compared to organisms from reference areas not affected by the same contamination due to their adaptation to harsh conditions. By contrast, the same organisms may be more sensitive to the new disturbance if chronic contamination kept them close to their tolerance limit. This study tested such alternatives by comparing the patterns of recovery from the experimental removal of all erect organisms of lowshore benthic assemblages between the post-industrial site of Bagnoli-Coroglio (Gulf of Naples) and reference sites located outside it. Recovery was assessed over six months. Response variables included mean values and temporal trajectories of assemblage structure, richness of taxa and abundance of conspicuous taxa. The examined assemblages showed great recovery ability that was comparable between the post-industrial site and reference sites. Discussed potential explanations include: (i) intertidal organisms would quickly recover irrespective of background contamination as an adaptation to the naturally harsh and variable environmental conditions of their living habitat; (ii) reference sites would be subject to environmental stress comparable to that of Bagnoli-Coroglio being located in the highly urbanized Gulf of Naples; (iii) large variability between- and withinsites may have masked any impacts of experimental disturbance and their differences between the post-industrial site and the reference sites; (iv) historical contamination would be limited to subtidal sediments, without propagating to adjacent rocky habitats.
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Vleminckx, Jason. "The influence of soil factors and anthropogenic disturbances on tree species assemblages in central African forests." Doctoral thesis, Universite Libre de Bruxelles, 2015. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209100.

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La diversité végétale exceptionnelle des forêts tropicales a toujours suscité une part d’incompréhension chez les scientifiques qui tentent de comprendre les processus à l’origine de cette diversité, ainsi que les mécanismes expliquant les changements spatiaux de composition spécifique. Une des clés de ce dernier mystère résiderait dans l’influence de la différentiation des niches écologiques, mais aussi de la dispersion limitée des graines et d’événements stochastiques (purement aléatoires et non prévisibles). La niche d’une espèce contraint celle-ci à s’établir dans un habitat présentant des gammes de conditions bien délimitées en termes de propriétés du sol (disponibilité en nutriments et toxicité de certains éléments) et d’intensité lumineuse. Par exemple, certaines espèces sont plus tolérantes à l’ombrage (espèces « sciaphiles ») que d’autres qui ne peuvent s’établir que dans des trouées forestières offrant suffisamment de lumière (espèces « héliophiles »). En Afrique centrale, les communautés d’arbres sont aujourd’hui en grande partie composées de ces espèces dites « héliophiles », alors que les ouvertures forestières naturelles sont rares. Il est fortement suspecté que la dominance de ces espèces soient la conséquence de trouées générées par l’homme qui, jusqu’au début de la période coloniale (vers 1900), occupait de vastes surfaces de forêt où il pratiquait l’agriculture sur brûlis. Cependant, peu d’études ont jusqu’à présent déterminé dans quelle mesure ces pratiques agricoles ont influencé la composition spécifique des forêts à l’échelle régionale comme à l’échelle locale.

L’objectif du présent travail est de faire la lumière sur l’impact de ces perturbations humaines mais aussi plus généralement sur l’influence relative de la niche écologique des espèces d’arbres par rapport à d’autres facteurs (dispersion limitée et facteurs stochastiques) sur leur distribution spatiale. Pour cela nous avons utilisé des données botaniques et environnementales provenant d’inventaires réalisés dans une forêt tropicale située en République Démocratique du Congo (quatre transects parallèles mesurant chacun 500 à 600 m de long), ainsi que des données similaires complémentées d’inventaires anthracologiques (estimation de la quantité de charbons de bois dans le sol, utilisée comme indicateur de feux passés d’origine anthropique) récoltées dans trois régions du sud du Cameroun (208 parcelles de 0,2 ha chacune).

Les données récoltées nous ont permis de mettre en évidence un impact significatif des propriétés physico-chimiques du sol sur la composition en espèces d’arbres. Plus précisément, nous avons pu constater une différence floristique marquée entre deux habitats très contrastés (sol sableux vs. sol argileux, Rép. Dém. Du Congo), et cela à une échelle spatiale locale (< 1 km²) où l’on pensait que de l’influence des facteurs stochastiques et de dispersion limitée étaient prépondérante. Mes analyses ont également démontré que cette différence était plus marquée pour les arbres de la canopée que pour les arbres des strates inférieures (« sous-canopée »), ce qui est sans doute lié au fait que de nombreux individus de la sous-canopée sont composés de juvéniles régénérant la canopée, parmi lesquels de nombreux arbres subissent une exclusion compétitive en cours (brouillant ainsi les signaux d’association espèce-habitat).

À une échelle spatiale beaucoup plus large cette fois (de 5 à 100 km, inventaires du Sud Cameroun), nous avons démontré que la diversité floristique était également influencée de manière significative par l’hétérogénéité spatiale de propriétés abiotiques du sol, notamment par les concentrations en (i) certains nutriments essentiels pouvant présenter des valeurs potentiellement limitantes (K, Mg, Ca et P) ainsi qu’en en (ii) élements pouvant être présents en quantités toxiques (Al et Mn). Cependant, alors que le signal environmental a été clairement détecté à l’échelle communautaire, seule les abondances d’une minorité d’espèces (< 15%) ont répondu significativement à la variation des conditions de sol. En outre, le nombre de réponses significatives a augmenté avec l’échelle d’observation ainsi qu’avec le degré d’hétérogénéité environnementale et/ou floristique. Pour mettre en évidence cet effet du sol, nous avons introduit une nouvelle approche permettant de tester la fraction d’une analyse de partition de variance correspondant à la part de variation floristique expliquée par l’effet de conditions édaphiques spatialement structurées (co-variation entre effets spatiaux et édaphiques), en combinant l’analyse de partition de variance avec des vecteurs propres de Moran (« Moran’s eigenvector maps ») et des translations toroïdales. Bien que cette méthode nous ait permis de déterminer si la fraction en question était significative, nous avons également mis en doute son interprétation habituelle suggérant que cette fraction représente une structure floristique directement induite par des structures spatiales de conditions de sol. Grâce à des simulations de populations végétales liées à des propriétés environnementales, nous avons mis en évidence que la valeur de la fraction étudiée ne semble finalement pas influencée par le degré de structuration spatiale des conditions environnementales, remettant donc en question l’utilité de l’analyse de partition de variance pour inférer des effets de processus écologiques sous-jacents sur la distribution spatiale des espèces d’arbres.

Enfin, les données floristiques et anthracologiques du Sud Cameroun ne nous ont pas permis de démontrer statistiquement l’hypothèse que les perturbations humaines passées sont en partie responsables de la dominance actuelle des espèces héliophiles. L’absence de corrélation significative entre l’abondance relative de ces espèces et la quantité de charbons de bois dans le sol peut s’expliquer par le fait que la majorité de ces charbons (60%) étaient trop vieux (1500 à 3000 ans) pour refléter des perturbations ayant influencé la diversité végétale présente.

Les conclusions générales de ma thèse de doctorat soutiennent que la niche écologique des espèces d’arbres des forêts tropicales africaines contribue de manière significative à déterminer leur assemblage dans l’espace, mais aussi que ces effets de niche dépendent fortement du contexte environnemental étudié ainsi que de l’échelle spatiale d’observation. Ce travail lève donc en partie un voile sur l’écologie des écosystèmes forestiers d’Afrique centrale qui restent largement méconnus par rapport à ceux d’Asie du Sud-Est et des régions néotropicales.


Doctorat en sciences, Spécialisation biologie végétale
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Books on the topic "Anthropogenic disturbances"

1

Harris, Mark Anglin. Geobiotechnological Solutions to Anthropogenic Disturbances. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-30465-6.

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J, Baird Donald, and Burton G. Allen, eds. Ecological variability: Separating natural from anthropogenic causes of ecosystem impairment. Pensacola, FL: SETAC Press, 2001.

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Untersuchungen zur Regenerationsfähigkeit arktischer und subarktischer Ökosysteme nach natürlichen und anthropogenen Störeinflüssen: Fallbeispiele aus Spitzbergen, den Selwyn/Mackenzie Mountains (West-Kanada) und Schwedisch-Lappland. Stuttgart: Franz Steiner Verlag, 2001.

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1959-, Flöser Götz, Tol, Richard S. J., 1969-, and SpringerLink (Online service), eds. Environmental Crises. Berlin, Heidelberg: Springer-Verlag Berlin Heidelberg, 2008.

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Santos, Ricardo Serrão, Christopher Kim Pham, and Jeroen Ingels, eds. Anthropogenic Disturbances in the Deep Sea. Frontiers Media SA, 2020. http://dx.doi.org/10.3389/978-2-88963-288-6.

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Harris, Mark Anglin. Geobiotechnological Solutions to Anthropogenic Disturbances: A Caribbean Perspective. Springer London, Limited, 2016.

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Harris, Mark. Geobiotechnological Solutions to Anthropogenic Disturbances: A Caribbean Perspective. Springer International Publishing AG, 2016.

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Harris, Mark Anglin. Geobiotechnological Solutions to Anthropogenic Disturbances: A Caribbean Perspective. Springer, 2018.

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Goldammer, J. G. Tropical Forests in Transition: Ecology of Natural and Anthropogenic Disturbance Processes. Birkhäuser, 2012.

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1949-, Goldammer J. G., ed. Tropical forests in transition: Ecology of natural and anthropogenic disturbance processes. Basel: Birkhäuser Verlag, 1992.

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Book chapters on the topic "Anthropogenic disturbances"

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Harris, Mark Anglin, and Samson N. Omoregie. "Post-mining Nutrient Depletion of Bauxite Overburdens in Jamaica: Storage Methods or Subsoil Dilution?" In Geobiotechnological Solutions to Anthropogenic Disturbances, 3–19. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-30465-6_1.

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Harris, Mark Anglin. "Structural Amelioration of Indurated Gypsum-Treated Bauxite Red Mud Tailings Using Bacterially Mediated Organic Treatments." In Geobiotechnological Solutions to Anthropogenic Disturbances, 257–77. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-30465-6_10.

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Harris, Mark Anglin, and Pichu Rengasamy. "Management of a Potential Mine Capping for Reclamation of Open-Cut Mines: Responses to Decomposable Organic Treatments." In Geobiotechnological Solutions to Anthropogenic Disturbances, 279–310. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-30465-6_11.

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Harris, Mark Anglin. "Erodibility of Unconsolidated Mine Wastes Under Simulated Rainfall and Hydraulic Forces After Organic Amendments." In Geobiotechnological Solutions to Anthropogenic Disturbances, 311–33. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-30465-6_12.

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Harris, Mark Anglin, and Mallavarapu Megharaj. "Modification of Hydraulic Conductivity and Aggregation in Pyritic Mine Tailings Materials with Sludge and Decomposable Phyto-Organics." In Geobiotechnological Solutions to Anthropogenic Disturbances, 335–68. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-30465-6_13.

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Harris, Mark Anglin. "Quenching of Phosphorus-Fixation in a Disturbed Caribbean Bauxite Mine Overburden Using Root Exudates: Implications for Acidic Tropical Soils." In Geobiotechnological Solutions to Anthropogenic Disturbances, 369–92. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-30465-6_14.

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Harris, Mark Anglin. "Cold-Water Starch Dissolution Bioreactors: Role in Treating Heap-Leached Wastewater from Precious Metal and REE Ores." In Geobiotechnological Solutions to Anthropogenic Disturbances, 393–406. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-30465-6_15.

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Harris, Mark Anglin. "Air, Land, and Water Contamination from Industrial Processing of Bitter Cassava: Implications for Pre-emptive Moisture-Pressure Combination Treatments." In Geobiotechnological Solutions to Anthropogenic Disturbances, 407–20. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-30465-6_16.

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Harris, Mark Anglin. "A Multiphase Outflow Purification System (MOPS) for Long-Term Sustainability of Acid Mine Drainage Detoxification and Metal Recovery." In Geobiotechnological Solutions to Anthropogenic Disturbances, 421–30. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-30465-6_17.

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Harris, Mark Anglin. "Dust Reduction in Bauxite Red Mud Waste using Carbonation, Gypsum & Flocculation." In Geobiotechnological Solutions to Anthropogenic Disturbances, 21–48. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-30465-6_2.

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Conference papers on the topic "Anthropogenic disturbances"

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Tomar, Simran, Pooja Nautiyal, Sunil Puri, Khilendra Singh Kanwal, and Kamaraj Chandra Sekar. "Impact of Anthropogenic Disturbances on Alpine Floristic Diversity along the Altitudinal Gradient of Northwestern Himalayas." In IECF 2022. Basel Switzerland: MDPI, 2022. http://dx.doi.org/10.3390/iecf2022-13093.

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Yang, Chang-Liang, Shi-Yu Li, Lin-Na Yuan, Liang-Xiu Yang, Hong-Zhou Zhang, and Wei-Hong Liu. "The Eutrophication Process in a Plateau Deepwater Lake: Response to the Changes of Anthropogenic Disturbances in the Watershed." In 2012 International Conference on Biomedical Engineering and Biotechnology (iCBEB). IEEE, 2012. http://dx.doi.org/10.1109/icbeb.2012.423.

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Wang, Qinxue, Tomohiro Okadera, Tadanobu Nakayama, Ochirbat Batkhishig, Dorjgotov Battogtokh, and Uudus Bayasaikhan. "Evaluation of the Influence of Anthropogenic Disturbances on Pasture Grazing Capacity and Its Vulnerability in Arid and Semi-Arid Regions." In Environmental Science and Technology International Conference (ESTIC 2021). Paris, France: Atlantis Press, 2021. http://dx.doi.org/10.2991/aer.k.211029.007.

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Maksimova, Ekaterina, Ekaterina Maksimova, Vladimir Zhigulsky, Vladimir Zhigulsky, Vladimir Shuisky, and Vladimir Shuisky. "ASSESSMENT OF THE SPATIOTEMPORAL DYNAMICS OF THE MACROPHYTE THICKET ECOSYSTEMS IN THE NEVA BAY AND THE ADJACENT WATERS OF THE EASTERN GULF OF FINLAND." In Managing risks to coastal regions and communities in a changing world. Academus Publishing, 2017. http://dx.doi.org/10.31519/conferencearticle_5b1b93849b8ce5.05692343.

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The macrophyte thicket ecosystems of higher aquatic vegetation in the Neva Bay (NB) and Eastern Gulf of Finland (EGoF) perform many important roles, including acting as the habitats, nesting sites and migration sites for aquatic and semi-aquatic birds, creating the specific conditions necessary for the spawning and growth of many species of fish, and taking part in the self-purification of the aquatic ecosystems. Many anthropogenic disturbances, hydraulic works in particular, have a significant negative impact on these macrophyte thicket ecosystems. In recent years, the active growth of a new type of macrophyte thicket has been observed in the NB. This is due to the aftereffects of the construction of the Saint Petersburg Flood Prevention Facility Complex (FPFC). It is quite likely that the total macrophyte thicket area in these waters is currently increasing. In the future, it will be necessary to assess the environmental impacts of the hydraulic works on the macrophyte thicket of the NB and EGoF, taking into account the background processes of the spatiotemporal dynamics of the reed beds in the waters in question. To do this, it will be necessary to carry out a comprehensive study of these ecosystems and identify patterns in their spatial and temporal dynamics. The program of the study has been developed and is currently being implemented by Eco-Express-Service, a St. Petersburg eco-design company.
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Maksimova, Ekaterina, Ekaterina Maksimova, Vladimir Zhigulsky, Vladimir Zhigulsky, Vladimir Shuisky, and Vladimir Shuisky. "ASSESSMENT OF THE SPATIOTEMPORAL DYNAMICS OF THE MACROPHYTE THICKET ECOSYSTEMS IN THE NEVA BAY AND THE ADJACENT WATERS OF THE EASTERN GULF OF FINLAND." In Managing risks to coastal regions and communities in a changing world. Academus Publishing, 2017. http://dx.doi.org/10.21610/conferencearticle_58b431672d7ed.

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The macrophyte thicket ecosystems of higher aquatic vegetation in the Neva Bay (NB) and Eastern Gulf of Finland (EGoF) perform many important roles, including acting as the habitats, nesting sites and migration sites for aquatic and semi-aquatic birds, creating the specific conditions necessary for the spawning and growth of many species of fish, and taking part in the self-purification of the aquatic ecosystems. Many anthropogenic disturbances, hydraulic works in particular, have a significant negative impact on these macrophyte thicket ecosystems. In recent years, the active growth of a new type of macrophyte thicket has been observed in the NB. This is due to the aftereffects of the construction of the Saint Petersburg Flood Prevention Facility Complex (FPFC). It is quite likely that the total macrophyte thicket area in these waters is currently increasing. In the future, it will be necessary to assess the environmental impacts of the hydraulic works on the macrophyte thicket of the NB and EGoF, taking into account the background processes of the spatiotemporal dynamics of the reed beds in the waters in question. To do this, it will be necessary to carry out a comprehensive study of these ecosystems and identify patterns in their spatial and temporal dynamics. The program of the study has been developed and is currently being implemented by Eco-Express-Service, a St. Petersburg eco-design company.
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Leal, Inara R. "Myrmecochory in brazilian Caatinga and its response to chronic anthropogenic disturbance." In 2016 International Congress of Entomology. Entomological Society of America, 2016. http://dx.doi.org/10.1603/ice.2016.91853.

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Noren, Dawn P., Marla M. Holt, Robin C. Dunkin, Nicole M. Thometz, and Terrie M. Williams. "Comparative and cumulative energetic costs of odontocete responses to anthropogenic disturbance." In 171st Meeting of the Acoustical Society of America. Acoustical Society of America, 2016. http://dx.doi.org/10.1121/2.0000357.

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Сёмкин, Б. И., and Л. И. Варченко. "FOUR-COMPONENT ECOLOGICAL INVARIANTS AND THEIR DISTURBANCE UNDER THE INFLUENCE OF ANTHROPOGENIC FACTORS." In Геосистемы Северо-Восточной Азии. Crossref, 2021. http://dx.doi.org/10.35735/tig.2021.65.50.044.

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Установлены существенные преимущества нового подхода, при котором многокомпонентными инвариантами являются относительные спектры. С использованием сравнительного анализа установлено постоянство многокомпонентных инвариантов и их изменение под воздействием антропогенных факторов. A general approach to the study of invariants in natural sciences is proposed. On examples using the traditional and new approaches, estimates of ecological and taxonomic invariants were made. Significant advantages of the new approach, in which relative spectra are multicomponent invariants, have been established. Using a comparative analysis, the constancy of multicomponent invariants and their change under the influence of anthropogenic factors have been established.
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Elo, Merja, Santtu Kareksela, Tuomas Haapalehto, Hilja Vuori, Kaisu Aapala, and Janne Kotiaho. "The mechanistic basis of changes in community assembly in relation to anthropogenic disturbance and productivity." In 5th European Congress of Conservation Biology. Jyväskylä: Jyvaskyla University Open Science Centre, 2018. http://dx.doi.org/10.17011/conference/eccb2018/107462.

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Zhao, Yinlin, Hongjie Wen, Bing Ren, Guoyu Wang, and Yongxue Wang. "An Improved SPH Model for Simulating Hydrodynamic Consequences Induced by Reef Degradation." In ASME 2020 39th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2020. http://dx.doi.org/10.1115/omae2020-18520.

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Abstract Coral reefs degradation accelerates in recent decades due to the natural disturbance and anthropogenic activities. It is important to predict and evaluate reasonably the hydrodynamic consequences of reef degradation. An improved weakly compressible smoothed particle hydrodynamic (WCSPH) porous model is developed based on the standard two-phase mixture theory. The developed WCSPH mixture model is validated by comparing the predicted results with the corresponding available data. The model is then adopted to predict the effects of reef degradation on the spatial distributions of wave setup, wave-induced current and low frequency wave energy over the reef-flat under the reef resonance conditions.
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Reports on the topic "Anthropogenic disturbances"

1

Raymond, Kara, Laura Palacios, and Evan Gwilliam. Status of climate and water resources at Big Bend National Park: Water year 2019. Edited by Tani Hubbard. National Park Service, September 2022. http://dx.doi.org/10.36967/2294267.

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Climate and hydrology are major drivers of ecosystem structure and function, particularly in arid and semi-arid ecosystems. Understanding changes in climate, groundwater, streamflow, and water quality is central to assessing the condition of park resources. This report combines data collected on climate, groundwater, and springs at Big Bend National Park (NP) to provide an integrated look at climate and water conditions during water year (WY) 2019 (October 2018–September 2019). However, this report does not address the Rio Grande or its tributaries. Annual precipitation was higher than normal (1981–2010) for Big Bend NP at four of the five National Oceanic and Atmospheric Administration Cooperative Observer Program weather stations: 111% of normal for Chisos Basin, 122% of normal for Panther Junction, 155% of normal for Persimmon Gap, and 124% of normal for Rio Grande Village. Castolon had 88% of normal annual precipitation. All five stations had higher than normal rainfall in October and December, while rainfall totals were substantially below normal at all stations in November, February, and March. Monthly precipitation totals for April through September were more variable from station to station. Mean monthly maximum air temperatures were below normal in the fall months, with Panther Junction as much as 7.5°F below normal in October. Monthly temperatures from January through July were more variable. Temperatures in August and September were warmer than normal at every station, up to +9.4°F at Rio Grande Village and +8.7°F at Chisos Basin in July. The reconnaissance drought index values indicate generally wetter conditions (based on precipitation and evaporative demand) at Chisos Basin since WY2016 and at Panther Junction and Persimmon Gap since WY2015, except for WY2017. This report presents the manual and automatic groundwater monitoring results at nine wells. Five wells had their highest water level in or just before WY2019: Panther Junction #10 peaked at 99.94 ft below ground surface (bgs) in September 2018, Contractor’s Well peaked at 31.43 ft bgs in November 2018, T-3 peaked at 65.39 ft bgs in December 2018, K-Bar #6 Observation Well peaked at 77.78 ft bgs in February 2019, and K-Bar #7 Observation Well peaked at 43.18 ft bgs in February 2019. This was likely in response to above normal rainfall in the later summer and fall 2018. The other monitoring wells did not directly track within-season precipitation. The last measurement at Gallery Well in WY2019 was 18.60 ft bgs. Gallery Well is located 120 feet from the river and closely tracked the Rio Grande stage, generally increasing in late summer or early fall following higher flow events. Water levels in Gambusia Well were consistently very shallow, though the manual well measurement collected in April was 4.25 ft bgs—relatively high for the monitoring record—and occurred outside the normal peak period of later summer and early fall. The last manual measurement taken at TH-10 in WY2019 was 34.80 ft bgs, only 0.45 ft higher than the earliest measurement in 1967, consistent with the lack of directional change in groundwater at this location, and apparently decoupled from within-season precipitation patterns. The last water level reading in WY2019 at Oak Springs #1 was 59.91 ft bgs, indicating an overall decrease of 26.08 ft since the well was dug in 1989. The Southwest Network Collaboration (SWNC) collects data on sentinel springs annually in the late winter and early spring following the network springs monitoring protocol. In WY2019, 18 sentinel site springs were visited at Big Bend NP (February 21, 2019–March 09, 2019). Most springs had relatively few indications of natural and anthropogenic disturbances. Natural disturbances included recent flooding, drying, and wildlife use. Anthropogenic disturbances included flow modifications (e.g., springboxes), hiking trails, and contemporary human use. Crews observed one to seven facultative/obligate wetland plant...
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Holt, Marla M., Dawn P. Noren, Robin Dunkin, and Terrie M. Williams. Comparative and Cumulative Energetic Costs of Odontocete Responses to Anthropogenic Disturbance. Fort Belvoir, VA: Defense Technical Information Center, September 2014. http://dx.doi.org/10.21236/ada616409.

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Dodd, Hope, David Peitz, Gareth Rowell, Janice Hinsey, David Bowles, Lloyd Morrison, Michael DeBacker, Jennifer Haack-Gaynor, and Jefrey Williams. Protocol for Monitoring Fish Communities in Small Streams in the Heartland Inventory and Monitoring Network. National Park Service, April 2021. http://dx.doi.org/10.36967/nrr-2284726.

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Fish communities are an important component of aquatic systems and are good bioindicators of ecosystem health. Land use changes in the Midwest have caused sedimentation, erosion, and nutrient loading that degrades and fragments habitat and impairs water quality. Because most small wadeable streams in the Heartland Inventory and Monitoring Network (HTLN) have a relatively small area of their watersheds located within park boundaries, these streams are at risk of degradation due to adjacent land use practices and other anthropogenic disturbances. Shifts in the physical and chemical properties of aquatic systems have a dramatic effect on the biotic community. The federally endangered Topeka shiner (Notropis topeka) and other native fishes have declined in population size due to habitat degradation and fragmentation in Midwest streams. By protecting portions of streams on publicly owned lands, national parks may offer refuges for threatened or endangered species and species of conservation concern, as well as other native species. This protocol describes the background, history, justification, methodology, data analysis and data management for long-term fish community monitoring of wadeable streams within nine HTLN parks: Effigy Mounds National Monument (EFMO), George Washington Carver National Monument (GWCA), Herbert Hoover National Historic Site (HEHO), Homestead National Monument of America (HOME), Hot Springs National Park (HOSP), Pea Ridge National Military Park (PERI), Pipestone National Monument (PIPE), Tallgrass Prairie National Preserve (TAPR), and Wilson's Creek national Battlefield (WICR). The objectives of this protocol are to determine the status and long-term trends in fish richness, diversity, abundance, and community composition in small wadeable streams within these nine parks and correlate the long-term community data to overall water quality and habitat condition (DeBacker et al. 2005).
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Williams, Terrie M. High Risk Behaviors in Marine Mammals: Linking Behavioral Responses to Anthropogenic Disturbance to Biological Consequences. Fort Belvoir, VA: Defense Technical Information Center, September 2013. http://dx.doi.org/10.21236/ada602529.

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Hayden, Heather. The Erosion of Coastal Sediment and Regeneration of Rhizophora mangle Following Anthropogenic Disturbance on Turneffe Atoll, Belize. Portland State University Library, January 2000. http://dx.doi.org/10.15760/etd.2363.

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Raymond, Kara, Laura Palacios, Cheryl McIntyre, and Evan Gwilliam. Status of climate and water resources at Saguaro National Park: Water year 2019. Edited by Alice Wondrak Biel. National Park Service, December 2021. http://dx.doi.org/10.36967/nrr-2288717.

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Climate and hydrology are major drivers of ecosystems. They dramatically shape ecosystem structure and function, particularly in arid and semi-arid ecosystems. Understanding changes in climate, groundwater, and water quality and quantity is central to assessing the condition of park biota and key cultural resources. The Sonoran Desert Network collects data on climate, groundwater, and surface water at 11 National Park Service units in south-ern Arizona and New Mexico. This report provides an integrated look at climate, groundwater, and springs conditions at Saguaro National Park (NP) during water year 2019 (October 2018–September 2019). Annual rainfall in the Rincon Mountain District was 27.36" (69.49 cm) at the Mica Mountain RAWS station and 12.89" (32.74 cm) at the Desert Research Learning Center Davis station. February was the wettest month, accounting for nearly one-quarter of the annual rainfall at both stations. Each station recorded extreme precipitation events (>1") on three days. Mean monthly maximum and minimum air temperatures were 25.6°F (-3.6°C) and 78.1°F (25.6°C), respectively, at the Mica Mountain station, and 37.7°F (3.2°C) and 102.3°F (39.1°C), respectively, at the Desert Research Learning Center station. Overall temperatures in WY2019 were cooler than the mean for the entire record. The reconnaissance drought index for the Mica Mountain station indicated wetter conditions than average in WY2019. Both of the park’s NOAA COOP stations (one in each district) had large data gaps, partially due to the 35-day federal government shutdown in December and January. For this reason, climate conditions for the Tucson Mountain District are not reported. The mean groundwater level at well WSW-1 in WY2019 was higher than the mean for WY2018. The water level has generally been increasing since 2005, reflecting the continued aquifer recovery since the Central Avra Valley Storage and Recovery Project came online, recharging Central Arizona Project water. Water levels at the Red Hills well generally de-clined starting in fall WY2019, continuing through spring. Monsoon storms led to rapid water level increases. Peak water level occurred on September 18. The Madrona Pack Base well water level in WY2019 remained above 10 feet (3.05 m) below measuring point (bmp) in the fall and winter, followed by a steep decline starting in May and continuing until the end of September, when the water level rebounded following a three-day rain event. The high-est water level was recorded on February 15. Median water levels in the wells in the middle reach of Rincon Creek in WY2019 were higher than the medians for WY2018 (+0.18–0.68 ft/0.05–0.21 m), but still generally lower than 6.6 feet (2 m) bgs, the mean depth-to-water required to sustain juvenile cottonwood and willow trees. RC-7 was dry in June–September, and RC-4 was dry in only September. RC-5, RC-6 and Well 633106 did not go dry, and varied approximately 3–4 feet (1 m). Eleven springs were monitored in the Rincon Mountain District in WY2019. Most springs had relatively few indications of anthropogenic or natural disturbance. Anthropogenic disturbance included spring boxes or other modifications to flow. Examples of natural disturbance included game trails and scat. In addition, several sites exhibited slight disturbance from fires (e.g., burned woody debris and adjacent fire-scarred trees) and evidence of high-flow events. Crews observed 1–7 taxa of facultative/obligate wetland plants and 0–3 invasive non-native species at each spring. Across the springs, crews observed four non-native plant species: rose natal grass (Melinis repens), Kentucky bluegrass (Poa pratensis), crimson fountaingrass (Cenchrus setaceus), and red brome (Bromus rubens). Baseline data on water quality and chemistry were collected at all springs. It is likely that that all springs had surface water for at least some part of WY2019. However, temperature sensors to estimate surface water persistence failed...
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7

Raymond, Kara, Laura Palacios, Cheryl McIntyre, and Evan Gwilliam. Status of climate and water resources at Chiricahua National Monument, Coronado National Memorial, and Fort Bowie National Historic Site: Water year 2019. National Park Service, May 2022. http://dx.doi.org/10.36967/nrr-2293370.

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Abstract:
Climate and hydrology are major drivers of ecosystems. They dramatically shape ecosystem structure and function, particularly in arid and semi-arid ecosystems. Understanding changes in climate, groundwater, and water quality and quantity is central to assessing the condition of park biota and key cultural resources. The Sonoran Desert Network collects data on climate, groundwater, and surface water at 11 National Park Service units in southern Arizona and New Mexico. This report provides an integrated look at climate, groundwater, and springs conditions at Chiricahua National Monument (NM), Coronado National Memorial (NMem), and Fort Bowie National Historic Site (NHS) during water year (WY) 2019 (October 2018–September 2019). Overall annual precipitation at Chiricahua NM and Coronado NMem in WY2019 was approximately the same as the normals for 1981–2010. (The weather station at Fort Bowie NHS had missing values on 275 days, so data were not presented for that park.) Fall and winter rains were greater than normal. The monsoon season was generally weaker than normal, but storm events related to Hurricane Lorena led to increased late-season rain in September. Mean monthly maximum temperatures were generally cooler than normal at Chiricahua, whereas mean monthly minimum temperatures were warmer than normal. Temperatures at Coronado were more variable relative to normal. The reconnaissance drought index (RDI) indicated that Chiricahua NM was slightly wetter than normal. (The WY2019 RDI could not be calculated for Coronado NMem due to missing data.) The five-year moving mean of annual precipitation showed both park units were experiencing a minor multi-year precipitation deficit relative to the 39-year average. Mean groundwater levels in WY2019 increased at Fort Bowie NHS, and at two of three wells monitored at Chiricahua NM, compared to WY2018. Levels in the third well at Chiricahua slightly decreased. By contrast, water levels declined in five of six wells at Coronado NMem over the same period, with the sixth well showing a slight increase over WY2018. Over the monitoring record (2007–present), groundwater levels at Chiricahua have been fairly stable, with seasonal variability likely caused by transpiration losses and recharge from runoff events in Bonita Creek. At Fort Bowie’s WSW-2, mean groundwater level was also relatively stable from 2004 to 2019, excluding temporary drops due to routine pumping. At Coronado, four of the six wells demonstrated increases (+0.30 to 11.65 ft) in water level compared to the earliest available measurements. Only WSW-2 and Baumkirchner #3 have shown net declines (-17.31 and -3.80 feet, respectively) at that park. Springs were monitored at nine sites in WY2019 (four sites at Chiricahua NM; three at Coronado NMem, and two at Fort Bowie NHS). Most springs had relatively few indications of anthropogenic or natural disturbance. Anthropogenic disturbance included modifications to flow, such as dams, berms, or spring boxes. Examples of natural disturbance included game trails, scat, or evidence of flooding. Crews observed 0–6 facultative/obligate wetland plant taxa and 0–3 invasive non-native species at each spring. Across the springs, crews observed six non-native plant species: common mullein (Verbascum thapsus), spiny sowthistle (Sonchus asper), common sowthistle (Sonchus oleraceus), Lehmann lovegrass (Eragrostis lehmanniana), rabbitsfoot grass (Polypogon monspeliensis), and red brome (Bromus rubens). Baseline data on water quality and water chemistry were collected at all nine sites. It is likely that that all nine springs had surface water for at least some part of WY2019, though temperature sensors failed at two sites. The seven sites with continuous sensor data had water present for most of the year. Discharge was measured at eight sites and ranged from < 1 L/minute to 16.5 L/minute.
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8

Short, Mary, and Sherry Leis. Vegetation monitoring in the Manley Woods unit at Wilson’s Creek National Battlefield: 1998–2020. Edited by Tani Hubbard. National Park Service, June 2022. http://dx.doi.org/10.36967/nrr-2293615.

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Natural resource management at Wilson’s Creek National Battlefield (NB) is guided by our understanding of the woodlands and prairies at the time of the Civil War battle in 1861. This report is focused on the Manley Woods unit of the park. This unit is an oak-hickory woodland in the Springfield Plain subsection of the Ozarks. Canopy closure for Missouri oak woodlands can be highly variable and ranges from 30–100% across the spectrum of savanna, open woodland, and closed woodland types. In 1861, the woodland was likely a savanna community. Changes in land use (e.g., fire exclusion) caused an increase in tree density in woodlands at Wilson’s Creek NB and across the Ozarks. Savannas and open woodlands transitioned to closed canopy woodlands over time. Park management plans include restoring the area to a savanna/open woodland structure. Prescribed fire was reintroduced to Wilson’s Creek NB in 1988 and continues as the primary mechanism for reducing the tree canopy. The Manley Woods unit of Wilson’s Creek NB has been subject to intense natural and anthropogenic disturbance events such as a tornado in 2003, timber removal in 2005, prescribed fires in 2006, 2009, and 2019, an ice storm in 2007, and periodic drought. The Heartland Inventory and Monitoring Network (hereafter, Heartland Network) installed four permanent monitoring sites within the Manley Woods area of the park in 1997. Initially, we assessed ground flora and regeneration within the sites (1998–1999). We added fuel sampling after the 2003 tornado. Although overstory sampling occurred prior to the tornado, the protocol was not yet stabilized and pre-2003 overstory data were not included in these analyses. In this report, we focus on the overstory, tree regeneration, and ground cover metrics; ground flora data will be assessed in future analyses. Heartland Network monitoring data reveal that Manley Woods has undergone substantial change in canopy cover and midstory trees since 1998. While basal area and density metrics classify Manley Woods as an open woodland, the closed canopy of the midstory and overstory reveal a plant community that is moving toward closed woodland or forest structure. The most recent fire in 2019 was patchy and mild, resulting in continued increases in fuels. Ground cover metrics indicate infrequent disturbance since leaf litter continued to increase. Management objectives to restore savanna or woodland composition and structure to the Manley Woods overstory, regeneration layer, and ground cover will require implementation of prescribed fire in the future. Repeated fires can thin midstory trees and limit less fire tolerant early seral species. Additionally, mechanical or chemical treatments to reduce undesirable tree species should be considered for woodland restoration. Decreasing canopy closure is an important and essential step toward the restoration of a functioning savanna/open woodland plant community in Manley Woods. Treatments that thin the midstory and reduce fuel loading will also benefit these plant communities. With the anticipated changing climate, maintaining an open woodland community type may also provide resilience through management for native species tolerant of increasingly warmer temperatures.
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