Journal articles on the topic 'Anthropogenically induced change'
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1
C.C., Asonye, Leslie T.A., Sodimu J., Fadipe O., and Kenai N.D. "Anthropogenically Induced Ecosystem Dysfunction and Human Health." African Journal of Environment and Natural Science Research 4, no. 3 (July 24, 2021): 48–58. http://dx.doi.org/10.52589/ajensr-w0lhry0n.
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Health is the most basic human right and one of the most important indicators of sustainable development. Individuals, communities and societies depend on healthy ecosystems support to remain healthy. Well-functioning ecosystems provide goods and services essential for human health. These goods and services include nutrition and food security, clean air and fresh water, medicines, cultural and spiritual values, and contributions to local livelihoods and economic development. They can also help to limit disease and stabilize the climate. However, over the years human activities have been constantly placing pressure on earth’s natural resources to meet the demands of the economies and the needs of a rapidly growing global population, which has resulted in the transformation of basic natural processes such as weather/climate, biogeochemical cycling, and more so the biological diversity in which the evolutionary changes depend. It is projected that less than 25% of Earth’s surface remains free from substantial impacts of human activities and the proportion is set to fall to a mere 10% or less by 2050. Constant human activities are resulting in soil, water and air pollution, increased emissions of greenhouse gases, deforestation and land use change, expanded urban areas, introduction of non-native species, and inadequately planned development of water and land resources to meet food and energy needs. These changes are having both direct and indirect impacts on our climate, ecosystems and biological diversity and human health. Thus, the integrated course of action that involves both individual and the government efforts must be instituted to tackle both human-induced drivers of biodiversity loss, disease emergence and the loss of ecosystem services that support health and general human well-being.
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Goman, Michelle, Arthur Joyce, and Raymond Mueller. "Stratigraphic evidence for anthropogenically induced coastal environmental change from Oaxaca, Mexico." Quaternary Research 63, no. 3 (May 2005): 250–60. http://dx.doi.org/10.1016/j.yqres.2005.02.008.
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Previous interdisciplinary paleoenvironmental and archaeological research along the Río Verde Valley of Oaxaca, Mexico, showed that Holocene erosion in the highland valleys of the upper drainage basin triggered geomorphic changes in the river's coastal floodplain. This article uses stratigraphic data from sediment cores extracted from Laguna Pastoría, an estuary in the lower Río Verde Valley, to examine changes in coastal geomorphology potentially triggered by highland erosion. Coastal lagoon sediments contain a stratigraphically and chronologically distinct record of major hurricane strikes during late Holocene times. Three distinct storm facies are identified from sediment cores obtained from Laguna Pastoría, which indicate that profound coastal environmental changes occurred within the region and are correlated with increased sediment supplied from highland erosion. The Chione/Laevicardium facies was deposited in an open bay while the Mytella/barnacle facies and sand facies were deposited in an enclosed lagoon following bay barrier formation. We argue that highland erosion triggered major geomorphic changes in the lowlands including bay barrier formation by ∼2500 cal yr B.P. These environmental changes may have had significant effects on human populations in the region. The lagoon stratigraphy further indicates an increase in mid–late Holocene hurricane activity, possibly caused by increased El Niño frequencies.
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Bissett, Andrew, Mark V. Brown, Steven D. Siciliano, and Peter H. Thrall. "Microbial community responses to anthropogenically induced environmental change: towards a systems approach." Ecology Letters 16 (May 2013): 128–39. http://dx.doi.org/10.1111/ele.12109.
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Apsimon, H., I. Thornton, W. Fyfe, Yetang Hong, J. Leggett, J. O. Nriagu, J. M. Pacyna, et al. "Anthropogenically induced global change — Report of working group 3, IUGS workshop on global change past and present." Palaeogeography, Palaeoclimatology, Palaeoecology 82, no. 1-2 (May 1990): 97–111. http://dx.doi.org/10.1016/s0031-0182(12)80024-1.
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Apsimon, H. "Anthropogenically induced global change — Report of working group 3, IUGS workshop on global change past and present." Global and Planetary Change 2, no. 1-2 (May 1990): 97–111. http://dx.doi.org/10.1016/0921-8181(90)90040-j.
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Strasser, A. "Global change and the decline of coral reefs." Geographica Helvetica 54, no. 3 (September 30, 1999): 125–31. http://dx.doi.org/10.5194/gh-54-125-1999.
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Abstract. Ever since coral reefs exist, changing environmental conditions have periodically led to their decline. However, within the perspective of geological time-spans, corals have always managed to re-install themselves. Today, human activity has enhanced stress factors and added new ones that cause a rapid and (on the human time-scale) irreversible decline of many reef ecosystems. The reasons for the disturbance of these complex communities are multiple, but global warming is a key factor. As a result, coral reefs lose their vital role of protecting coastal areas from flooding and storm impact and of creating habitats for numerous marine organisms. In this short article, natural and anthropogenically induced stress factors are discussed, and measures for mitigating or stopping coral-reef decline are proposed.
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Schallenberg, Marc, and Émilie Saulnier-Talbot. "Trajectory of an anthropogenically induced ecological regime shift in a New Zealand shallow coastal lake." Marine and Freshwater Research 67, no. 10 (2016): 1522. http://dx.doi.org/10.1071/mf15211.
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This study examines environmental change over the post-colonial period at Wainono (South Canterbury, New Zealand), a coastal lagoon and wetland of national and international significance for native birds and fish, currently targeted for restoration. In order to better understand the recent trajectory of this ecosystem, a multi-proxy palaeolimnological approach was adopted, including the analysis of core composition, and diatom and macrofossil assemblages in sedimentary archives. Results indicated that a combination of land-use changes in the catchment and water-level control, by an artificial connection to the sea, transformed this shallow lake from a freshwater macrophyte-dominated state to a brackish, hypertrophic system with little or no macrophytes. The reconstruction corroborates the trajectory of stressors gleaned from historical reports of changes in and around Wainono Lagoon, as well as reported trajectories from other coastal lakes and lagoons of the east coast of the South Island of New Zealand and elsewhere around the world. This study adds to the evidence that such ecosystems are ecologically vulnerable and in need of careful management to safeguard the important biodiversity and provisioning values that they afford. It also highlights the usefulness of the palaeolimnological approach in providing substantial information for improving sustainable management and restoration strategies for shallow lakes.
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Blattmann, Thomas M., Martin Wessels, Cameron P. McIntyre, and Timothy I. Eglinton. "Projections for Future Radiocarbon Content in Dissolved Inorganic Carbon in Hardwater Lakes: A Retrospective Approach." Radiocarbon 60, no. 3 (March 4, 2018): 791–800. http://dx.doi.org/10.1017/rdc.2018.12.
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ABSTRACTInland water bodies contain significant amounts of carbon in the form of dissolved inorganic carbon (DIC) derived from a mixture of modern atmospheric and pre-aged sources, which needs to be considered in radiocarbon-based dating and natural isotope tracer studies. While reservoir effects in hardwater lakes are generally considered to be constant through time, a comparison of recent and historical DI14C data from 2013 and 1969 for Lake Constance reveals that this is not a valid assumption. We hypothesize that changes in atmospheric carbon contributions to lake water DIC have taken place due to anthropogenically forced eutrophication in the 20th century. A return to more oligotrophic conditions in the lake led to reoxygenation and enhanced terrigenous organic matter remineralization, contributing to lake water DIC. Such comparisons using DI14C measurements from different points in time enable nonlinear changes in lake water DIC source and signature to be disentangled from concurrent anthropogenically induced changes in atmospheric 14C. In the future, coeval changes in lake dynamics due to climate change are expected to further perturb these balances. Depending on the scenario, Lake Constance DI14C is projected to decrease from the 2013 measured value of 0.856 Fm to 0.54–0.62 Fm by the end of the century.
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van Elk, Jan, Stephen J. Bourne, Steve J. Oates, Julian J. Bommer, Rui Pinho, and Helen Crowley. "A Probabilistic Model to Evaluate Options for Mitigating Induced Seismic Risk." Earthquake Spectra 35, no. 2 (May 2019): 537–64. http://dx.doi.org/10.1193/050918eqs118m.
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Common responses to induced seismicity are based on control of the anthropogenic activity causing the earthquakes, such as fluid injection or withdrawal, in order to limit either the magnitudes of the events or the level of ground motion to within established thresholds. An alternative risk-mitigation option is seismic retrofitting of the more vulnerable buildings potentially exposed to the ground shaking to reduce the risk to acceptable levels. Optimal mitigation strategies may combine both production control and structural strengthening, for which a probabilistic risk model is required that can estimate the change in hazard caused by production or injection variations and the changes in fragility resulting from structural interventions. Such a risk model has been developed for the Groningen gas field in the Netherlands. The framework for this risk model to inform decision making regarding mitigation strategies can be adapted to other cases of anthropogenically induced seismicity.
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Hill, Spencer A., Yi Ming, and Isaac M. Held. "Mechanisms of Forced Tropical Meridional Energy Flux Change." Journal of Climate 28, no. 5 (February 26, 2015): 1725–42. http://dx.doi.org/10.1175/jcli-d-14-00165.1.
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Abstract Anthropogenically forced changes to the mean and spatial pattern of sea surface temperatures (SSTs) alter tropical atmospheric meridional energy transport throughout the seasonal cycle—in total, its partitioning between the Hadley cells and eddies and, for the Hadley cells, the relative roles of the mass flux and the gross moist stability (GMS). The authors investigate this behavior using an atmospheric general circulation model forced with SST anomalies caused by either historical greenhouse gas or aerosol forcing, dividing the SST anomalies into two components: the tropical mean SST anomaly applied uniformly and the full SST anomalies minus the tropical mean. For greenhouse gases, the polar-amplified SST spatial pattern partially negates enhanced eddy poleward energy transport driven by mean warming. Both SST components weaken winter Hadley cell circulation and alter GMS. The Northern Hemisphere–focused aerosol cooling induces northward energy flux anomalies in the deep tropics, which manifest partially via strengthened northern and weakened southern Hadley cell overturning. Aerosol-induced GMS changes also contribute to the northward energy fluxes. A simple thermodynamic scaling qualitatively captures these changes, although it performs less well for the greenhouse gas simulations. The scaling provides an explanation for the tight correlation demonstrated in previous studies between shifts in the intertropical convergence zone and cross-equatorial energy fluxes.
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Safriel, Uriel N., Sergei Volis, and Salit Kark. "CORE AND PERIPHERAL POPULATIONS AND GLOBAL CLIMATE CHANGE." Israel Journal of Plant Sciences 42, no. 4 (May 13, 1994): 331–45. http://dx.doi.org/10.1080/07929978.1994.10676584.
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Environmental conditions outside the periphery of a species' distribution prevent population persistence, hence peripheral populations live under conditions different from those of core populations. Peripheral areas are characterized by variable and unstable conditions, relative to core areas. Peripheral populations are expected to be genetically more variable, since the variable conditions induce fluctuating selection, which maintains high genetic diversity. Alternatively, due to marginal ecological conditions at the periphery, populations there are small and isolated; the within-population diversity is low, but the between-population genetic diversity is high due to genetic drift. It is also likely that peripheral populations evolve resistance to extreme conditions. Thus, peripheral populations rather than core ones may be resistant to environmental extremes and changes, such as global climate change induced by the anthropogenically emitted “greenhouse gases”. They should be treated as a biogenetic resource used for rehabilitation and restoration of damaged ecosystems. Climatic transition zones are characterized by a high incidence of species represented by peripheral populations, and therefore should be conserved now as repositories of these resources, to be used in the future for mitigating undesirable effects of global climate change. Preliminary research revealed high phenotypic variability and high genetic diversity in peripheral populations relative to core populations of wild barley and the chukar partridge, respectively.
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Mieszkowska, N., H. Sugden, L. B. Firth, and S. J. Hawkins. "The role of sustained observations in tracking impacts of environmental change on marine biodiversity and ecosystems." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 372, no. 2025 (September 28, 2014): 20130339. http://dx.doi.org/10.1098/rsta.2013.0339.
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Marine biodiversity currently faces unprecedented threats from multiple pressures arising from human activities. Global drivers such as climate change and ocean acidification interact with regional eutrophication, exploitation of commercial fish stocks and localized pressures including pollution, coastal development and the extraction of aggregates and fuel, causing alteration and degradation of habitats and communities. Segregating natural from anthropogenically induced change in marine ecosystems requires long-term, sustained observations of marine biota. In this review, we outline the history of biological recording in the coastal and shelf seas of the UK and Ireland and highlight where sustained observations have contributed new understanding of how anthropogenic activities have impacted on marine biodiversity. The contributions of sustained observations, from those collected at observatories, single station platforms and multiple-site programmes to the emergent field of multiple stressor impacts research, are discussed, along with implications for management and sustainable governance of marine resources in an era of unprecedented use of the marine environment.
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Lema, Sean C., Samantha L. Bock, Morgan M. Malley, and Emma A. Elkins. "Warming waters beget smaller fish: evidence for reduced size and altered morphology in a desert fish following anthropogenic temperature change." Biology Letters 15, no. 10 (October 2019): 20190518. http://dx.doi.org/10.1098/rsbl.2019.0518.
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Poikilothermic organisms are predicted to show reduced body sizes as they experience warming environments under a changing global climate. Such a shrinking of size is expected under scenarios where rising temperatures increase cellular reaction rates and basal metabolic energy demands, therein requiring limited energy to be shifted from growth. Here, we provide evidence that the ecological changes associated with warming may not only lead to shrinking body size but also trigger shifts in morphology. We documented 33.4 and 39.0% declines in body mass and 7.2 and 7.6% reductions in length for males and females, respectively, in a wild population of Amargosa pupfish, Cyprinodon nevadensis amargosae , following an abrupt anthropogenically driven temperature increase. That reduction in size was accompanied by the partial or complete loss of paired pelvic fins in approximately 34% of the population, a morphological change concomitant with altered body dimensions including head size and body depth. These observations confirm that increasing temperatures can reduce body size under some ecological scenarios and highlight how human-induced environmental warming may also trigger morphological changes with potential relevance for fitness.
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Jordan, Hannah, Francesca Cigna, and Luke Bateson. "Identifying natural and anthropogenically-induced geohazards from satellite ground motion and geospatial data: Stoke-on-Trent, UK." International Journal of Applied Earth Observation and Geoinformation 63 (December 2017): 90–103. http://dx.doi.org/10.1016/j.jag.2017.07.003.
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Makarieva, Anastassia, Victor G. Gorshkov, Brendan Mackey, and Vadim V. Gorshkov. "How Valid are the Biological and Ecological Principles Underpinning Global Change Science?" Energy & Environment 13, no. 3 (July 2002): 299–310. http://dx.doi.org/10.1260/095830502320268142.
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The prevailing scientific approach to investigating and understanding the environmental consequences of human-induced global change is underpinned by two basic biological principles. First, the principle that species genetically adapt to changing environment conditions. Second, the principle that nutrients present in the environment in the smallest relative concentrations limit biological productivity. We contend that both principles have been formulated based on the results of investigations into either artificially selected organisms, or anthropogenically perturbed landscapes. In both these cases, organisms are studied outside their natural ecological niche. We argue that natural ecosystems do not conform to the above two principles. Non-perturbed biota of natural ecological communities form and maintain optimal environment conditions by buffering the flux of primary environmental resources that would otherwise randomly fluctuate as the result of purely physical processes. In such a biotically-mediated environment the availability of nutrients does not limit biological productivity. Critically, the capacity of the biota to regulate local environment conditions obviates the need for species to continually adapt to random environmental fluctuations. We illustrate how the failure to distinguish between the functioning of perturbed and unperturbed biota prevents the development of policies and strategies that will lead to the long term resolution of the global ecological crisis.
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Alewell, C., R. Giesler, J. Klaminder, J. Leifeld, and M. Rollog. "Stable carbon isotopes as indicators for environmental change in palsa peats." Biogeosciences 8, no. 7 (July 8, 2011): 1769–78. http://dx.doi.org/10.5194/bg-8-1769-2011.
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Abstract. Palsa peats are unique northern ecosystems formed under an arctic climate and characterized by a high biodiversity and sensitive ecology. The stability of the palsas are seriously threatened by climate warming which will change the permafrost dynamic and induce a degradation of the mires. We used stable carbon isotope depth profiles in two palsa mires of Northern Sweden to track environmental change during the formation of the mires. Soils dominated by aerobic degradation can be expected to have a clear increase of carbon isotopes (δ13C) with depth, due to preferential release of 12C during aerobic mineralization. In soils with suppressed degradation due to anoxic conditions, stable carbon isotope depth profiles are either more or less uniform indicating no or very low degradation or depth profiles turn to lighter values due to an enrichment of recalcitrant organic substances during anaerobic mineralisation which are depleted in 13C. The isotope depth profile of the peat in the water saturated depressions (hollows) at the yet undisturbed mire Storflaket indicated very low to no degradation but increased rates of anaerobic degradation at the Stordalen site. The latter might be induced by degradation of the permafrost cores in the uplifted areas (hummocks) and subsequent breaking and submerging of the hummock peat into the hollows due to climate warming. Carbon isotope depth profiles of hummocks indicated a turn from aerobic mineralisation to anaerobic degradation at a peat depth between 4 and 25 cm. The age of these turning points was 14C dated between 150 and 670 yr and could thus not be caused by anthropogenically induced climate change. We found the uplifting of the hummocks due to permafrost heave the most likely explanation for our findings. We thus concluded that differences in carbon isotope profiles of the hollows might point to the disturbance of the mires due to climate warming or due to differences in hydrology. The characteristic profiles of the hummocks are indicators for micro-geomorphic change during permafrost up heaving.
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Sierra, C. A., M. E. Harmon, E. Thomann, S. S. Perakis, and H. W. Loescher. "Amplification and dampening of soil respiration by changes in temperature variability." Biogeosciences Discussions 7, no. 6 (December 10, 2010): 8979–9008. http://dx.doi.org/10.5194/bgd-7-8979-2010.
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Abstract. Accelerated release of carbon from soils is one of the most important feedbacks related to anthropogenically induced climate change. Studies addressing the mechanisms for soil carbon release through organic matter decomposition have focused on the effect of changes in the average temperature, with little attention to changes in temperature variability. Anthropogenic activities are likely to modify both the average state and the variability of the climatic system; therefore, the effects of future warming on decomposition should not only focus on trends in the average temperature, but also variability expressed as a change of the probability distribution of temperature. Using analytical and numerical analyses we tested common relationships between temperature and respiration and found that the variability of temperature plays an important role determining respiration rates of soil organic matter. Changes in temperature variability, without changes in the average temperature, can affect the amount of carbon released through respiration over the long-term. Furthermore, simultaneous changes in the average and variance of temperature can either amplify or dampen the release of carbon through soil respiration as climate regimes change. These effects depend on the degree of convexity of the relationship between temperature and respiration and the magnitude of the change in temperature variance. A potential consequence of this effect of variability would be higher respiration in regions where both the mean and variance of temperature are expected to increase, such as in some low latitude regions; and lower amounts of respiration where the average temperature is expected to increase and the variance to decrease, such as in northern high latitudes.
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Sierra, C. A., M. E. Harmon, E. Thomann, S. S. Perakis, and H. W. Loescher. "Amplification and dampening of soil respiration by changes in temperature variability." Biogeosciences 8, no. 4 (April 19, 2011): 951–61. http://dx.doi.org/10.5194/bg-8-951-2011.
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Abstract. Accelerated release of carbon from soils is one of the most important feedbacks related to anthropogenically induced climate change. Studies addressing the mechanisms for soil carbon release through organic matter decomposition have focused on the effect of changes in the average temperature, with little attention to changes in temperature variability. Anthropogenic activities are likely to modify both the average state and the variability of the climatic system; therefore, the effects of future warming on decomposition should not only focus on trends in the average temperature, but also variability expressed as a change of the probability distribution of temperature. Using analytical and numerical analyses we tested common relationships between temperature and respiration and found that the variability of temperature plays an important role determining respiration rates of soil organic matter. Changes in temperature variability, without changes in the average temperature, can affect the amount of carbon released through respiration over the long-term. Furthermore, simultaneous changes in the average and variance of temperature can either amplify or dampen the release of carbon through soil respiration as climate regimes change. These effects depend on the degree of convexity of the relationship between temperature and respiration and the magnitude of the change in temperature variance. A potential consequence of this effect of variability would be higher respiration in regions where both the mean and variance of temperature are expected to increase, such as in some low latitude regions; and lower amounts of respiration where the average temperature is expected to increase and the variance to decrease, such as in northern high latitudes.
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Ives, M. C., J. P. Scandol, S. S. Montgomery, and I. M. Suthers. "Modelling the possible effects of climate change on an Australian multi-fleet prawn fishery." Marine and Freshwater Research 60, no. 12 (2009): 1211. http://dx.doi.org/10.1071/mf07110.
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The relationship between fisheries and climate has been given renewed emphasis owing to increasing concern regarding anthropogenically induced climate change. This relationship is particularly important for estuarine fisheries, where there are documented correlations between river discharge and productivity. The commercial catch of school prawns (Metapenaeus macleayi) has been shown to be positively correlated with the rates of river discharge in northern New South Wales, Australia. In the present study, a simulation model was developed to analyse the dynamics of the stock for 10 years under alternative river discharge scenarios, and the effectiveness of a series of management strategies under these scenarios was examined. A size-based metapopulation model was developed that incorporated the dynamics of school prawn populations in three habitats being harvested by three different fishing methods. The model indicated that both the growth and movement of prawns were affected by the rates of river discharge, and that higher rates of river discharge usually generated increased commercial catches, but this outcome was not certain. It was concluded that the population does not appear to be overexploited and that none of the three alternative management strategies performed better within the model than the current spatio-temporal closures, even under a wide range of river discharge scenarios.
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Potapov, Peter, Svetlana Turubanova, Ilona Zhuravleva, Matthew Hansen, Alexey Yaroshenko, and Alexander Manisha. "Forest Cover Change within the Russian European North after the Breakdown of Soviet Union (1990–2005)." International Journal of Forestry Research 2012 (2012): 1–11. http://dx.doi.org/10.1155/2012/729614.
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Forest cover dynamics (defined as tree canopy cover change without regard to forest land use) within the Russian European North have been analyzed from 1990 to 2005 using a combination of results from two Landsat-based forest cover monitoring projects: 1990–2000 and 2000–2005. Results of the forest cover dynamics analysis highlighted several trends in forest cover change since the breakdown of the Soviet planned economy. While total logging area decreased from the 1990–2000 to the 2000–2005 interval, logging and other forms of anthropogenically-induced clearing increased within the Central and Western parts of the region. The most populated regions of European Russia featured the highest rates of net forest cover loss. Our results also revealed intensive gross forest cover loss due to forest felling close to the Russian-Finland border. The annual burned forest area almost doubled between the two time intervals. The 2000–2005 gross forest cover gain results suggest that tree encroachment on abandoned agriculture land is a wide-spread process over the region. The analysis demonstrates the value of regional-scale Landsat-based forest cover and change quantification. Our results supplemented official data by providing independently derived spatial information that could be used for assessing on-going trends and serve as a baseline for future forest cover monitoring.
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López-Sáez, José Antonio, Sebastián Pérez-Díaz, Didier Galop, Francisca Alba-Sánchez, and Daniel Abel-Schaad. "A Late Antique Vegetation History of the Western Mediterranean in Context." Late Antique Archaeology 11, no. 1 (October 3, 2015): 83–104. http://dx.doi.org/10.1163/22134522-12340054.
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AbstractFossil pollen records from 70 sites with reliable chronologies and high-resolution data in the western Mediterranean, were synthesised to document Late Holocene vegetation and climate change. The key elements of vegetation dynamics and landscape construction during Late Antiquity are clear in the light of the fossil pollen records. These are: fire events (natural or anthropogenically induced); grazing activities in high-mountain areas; agriculture; arboriculture; and human settlement in the lowlands. In terms of anthropogenic pressure, the differences recorded between highlands and lowlands suggest an imbalance in land use. Such practices were related to three main types of activities: wood exploitation and management, cultivation, and pastoralism. In lowland areas there seems to be some synchronism in vegetation dynamics during the late antique period, since most of the territories of the western Mediterranean had been deforested by the Early Roman period. However, in mountainous regions, pollen records document a clear asynchrony.
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Palikhe, Bhakta R. "Relationship between pesticide use and climate change for crops." Journal of Agriculture and Environment 8 (December 26, 2007): 83–91. http://dx.doi.org/10.3126/aej.v8i0.731.
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The use (and abuse) of pesticides has increased to combat insect-pests and diseases. However, the major causes concern of are the undesirable side effects of these chemicals on biodiversity, environment, food quality and human health .Climate change will have important implications for insect conservation and pest status. Climate and weather can substantially influence the development and distribution of insects. Most of the warming over the last 50 years is likely to have been due to man-made activities. Anthropogenically induced climatic change arising from increasing levels of atmospheric greenhouse gases would, therefore, be likely to have a significant effect on agricultural insect pests. Current best estimates of changes in climate indicate an increase in global mean annual temperatures of 1[o] C by 2025 and 3[o]C by the end of the next century. Such increases in temperature have a number of implications for temperature-dependent insect pests. The Assessment investigates the relationship between pesticide use and climate for crops that require relatively large amounts of pesticide. This paper describes such input-driven agriculture, the problem of pests and diseases and the unsustainable agricultural practices that it leads to, and the socio-economic and health externalities resulting in farmer's distress in pesticide hot spots. To protect ourselves, our economy, and our land from the adverse effects of climate change, we must ultimately dramatically reduce emissions of carbon dioxide and other greenhouse gases. The causes of anthropogenic climate change are broad and often difficult to address. There is no single solution to this complex problem, but numerous opportunities exist for reducing problems of climate change. The issue of climate change is one of the most profound challenges of our time, and we believe it is a challenge that can be met.
The Journal of AGRICULTURE AND ENVIRONMENT Vol. 8, 2007, pp. 83-91
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Alewell, C., R. Giesler, J. Klaminder, J. Leifeld, and M. Rollog. "Stable carbon isotopes as indicators for micro-geomorphic changes in palsa peats." Biogeosciences Discussions 8, no. 1 (January 19, 2011): 527–48. http://dx.doi.org/10.5194/bgd-8-527-2011.
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Abstract. Palsa peats are unique northern ecosystems formed under an arctic climate and characterized by an unique biodiversity and ecology. The stability of the palsas are seriously threatened by climate warming which will change the permafrost dynamic and results in degradation of the mires. We used stable carbon isotope depth profiles in two palsa mires of Northern Sweden to track environmental change during the formation of the mires. Carbon isotope (δ13C) depth profile of the yet undisturbed mire Storflaket indicated very low to no degradation of the peat in the water saturated depressions (hollows) but increased rates of anaerobic degradation at the Stordalen site. The latter might be induced by degradation of the permafrost cores in the uplifted areas (hummocks) and subsequent braking and submerging of the hummock peat into the hollows due to climate warming. Carbon isotope depth profiles of hummocks indicated a turn from aerobic mineralisation to anaerobic degradation at a peat depth between 4 to 25 cm. The age of these turning point was 14C dated between 150 and 670 years and could thus not be caused by anthropogenically induced climate change. We found the uplifting of the hummocks due to permafrost heave the most likely explanation for our findings. We thus concluded that differences in carbon isotope profiles of the hollows might point to the disturbance of the mires due to climate warming or due to differences in hydrology. The characteristic profiles of the hummocks are indicators for micro-geomorphic change during permafrost up heaving.
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Evans, Matthew R., Ken J. Norris, and Tim G. Benton. "Predictive ecology: systems approaches." Philosophical Transactions of the Royal Society B: Biological Sciences 367, no. 1586 (January 19, 2012): 163–69. http://dx.doi.org/10.1098/rstb.2011.0191.
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The world is experiencing significant, largely anthropogenically induced, environmental change. This will impact on the biological world and we need to be able to forecast its effects. In order to produce such forecasts, ecology needs to become more predictive—to develop the ability to understand how ecological systems will behave in future, changed, conditions. Further development of process-based models is required to allow such predictions to be made. Critical to the development of such models will be achieving a balance between the brute-force approach that naively attempts to include everything, and over simplification that throws out important heterogeneities at various levels. Central to this will be the recognition that individuals are the elementary particles of all ecological systems. As such it will be necessary to understand the effect of evolution on ecological systems, particularly when exposed to environmental change. However, insights from evolutionary biology will help the development of models even when data may be sparse. Process-based models are more common, and are used for forecasting, in other disciplines, e.g. climatology and molecular systems biology. Tools and techniques developed in these endeavours can be appropriated into ecological modelling, but it will also be necessary to develop the science of ecoinformatics along with approaches specific to ecological problems. The impetus for this effort should come from the demand coming from society to understand the effects of environmental change on the world and what might be performed to mitigate or adapt to them.
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Rutter, Ernest, and Abigail Hackston. "On the effective stress law for rock-on-rock frictional sliding, and fault slip triggered by means of fluid injection." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 375, no. 2103 (August 21, 2017): 20160001. http://dx.doi.org/10.1098/rsta.2016.0001.
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Fluid injection into rocks is increasingly used for energy extraction and for fluid wastes disposal, and can trigger/induce small- to medium-scale seismicity. Fluctuations in pore fluid pressure may also be associated with natural seismicity. The energy release in anthropogenically induced seismicity is sensitive to amount and pressure of fluid injected, through the way that seismic moment release is related to slipped area, and is strongly affected by the hydraulic conductance of the faulted rock mass. Bearing in mind the scaling issues that apply, fluid injection-driven fault motion can be studied on laboratory-sized samples. Here, we investigate both stable and unstable induced fault slip on pre-cut planar surfaces in Darley Dale and Pennant sandstones, with or without granular gouge. They display contrasting permeabilities, differing by a factor of 10 5 , but mineralogies are broadly comparable. In permeable Darley Dale sandstone, fluid can access the fault plane through the rock matrix and the effective stress law is followed closely. Pore pressure change shifts the whole Mohr circle laterally. In tight Pennant sandstone, fluid only injects into the fault plane itself; stress state in the rock matrix is unaffected. Sudden access by overpressured fluid to the fault plane via hydrofracture causes seismogenic fault slips. This article is part of the themed issue ‘Faulting, friction and weakening: from slow to fast motion’.
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Pettit, Lachlan, Mathew S. Crowther, Georgia Ward-Fear, and Richard Shine. "Divergent long-term impacts of lethally toxic cane toads (Rhinella marina) on two species of apex predators (monitor lizards, Varanus spp.)." PLOS ONE 16, no. 7 (July 22, 2021): e0254032. http://dx.doi.org/10.1371/journal.pone.0254032.
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Biological invasions can massively disrupt ecosystems, but evolutionary and ecological adjustments may modify the magnitude of that impact through time. Such post-colonisation shifts can change priorities for management. We quantified the abundance of two species of giant monitor lizards, and of the availability of their mammalian prey, across 45 sites distributed across the entire invasion trajectory of the cane toad (Rhinella marina) in Australia. One varanid species (Varanus panoptes from tropical Australia) showed dramatic population collapse with toad invasion, with no sign of recovery at most (but not all) sites that toads had occupied for up to 80 years. In contrast, abundance of the other species (Varanus varius from eastern-coastal Australia) was largely unaffected by toad invasion. That difference might reflect availability of alternative food sources in eastern-coastal areas, perhaps exacerbated by the widespread prior collapse of populations of small mammals across tropical (but not eastern) Australia. According to this hypothesis, the impact of cane toads on apex predators has been exacerbated and prolonged by a scarcity of alternative prey. More generally, multiple anthropogenically-induced changes to natural ecosystems may have synergistic effects, intensifying the impacts beyond that expected from either threat in isolation.
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Tsigaridis, K., M. Krol, F. J. Dentener, Y. Balkanski, J. Lathière, S. Metzger, D. A. Hauglustaine, and M. Kanakidou. "Change in global aerosol composition since preindustrial times." Atmospheric Chemistry and Physics Discussions 6, no. 3 (June 28, 2006): 5585–628. http://dx.doi.org/10.5194/acpd-6-5585-2006.
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Abstract. To elucidate human induced changes of aerosol load and composition in the atmosphere, a coupled aerosol and gas-phase chemistry transport model of the troposphere and lower stratosphere has been used. This is the first 3-d modeling study that focuses on aerosol chemical composition change since preindustrial times considering the secondary organic aerosol formation together with all other main aerosol components including nitrate. In particular, we evaluate non-sea-salt sulfate (nss-SO4=), ammonium (NH4+), nitrate (NO3-), black carbon (BC), sea-salt, dust, primary and secondary organics (POA and SOA) with a focus on the importance of secondary organic aerosols. Our calculations show that the aerosol optical depth (AOD) has increased by about 21% since preindustrial times. This enhancement of AOD is attributed to a rise in the atmospheric load of BC, nss-SO4=, NO3-, POA and SOA by factors of 3.3, 2.6, 2.7, 2.3 and 1.2, respectively, whereas we assumed that the natural dust and sea-salt sources remained constant. The nowadays increase in carbonaceous aerosol loading is dampened by a 34–42% faster conversion of hydrophobic to hydrophilic carbonaceous aerosol leading to higher removal rates. These changes between the various aerosol components resulted in significant modifications of the aerosol chemical composition. The relative importance of the various aerosol components is critical for the aerosol climatic effect, since atmospheric aerosols behave differently when their chemical composition changes. According to this study, the aerosol composition changed significantly over the different continents and with height since preindustrial times. The presence of anthropogenically emitted primary particles in the atmosphere facilitates the condensation of the semi-volatile species that form SOA onto the aerosol phase, particularly in the boundary layer. The SOA burden that is dominated by the natural component has increased by 24% while its contribution to the AOD has increased by 11%. The increase in oxidant levels and preexisting aerosol mass since preindustrial times is the reason of the burden change, since emissions have not changed significantly. The computed aerosol composition changes translate into about 2.5 times more water associated with non sea-salt aerosol. Additionally, aerosols contain 2.7 times more inorganic components nowadays than during the preindustrial times. We find that the increase in emissions of inorganic aerosol precursors is much larger than the corresponding aerosol increase, reflecting a non-linear atmospheric response.
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Boest-Petersen, Alexander, Piotr Michalak, and Jamal Jokar Arsanjani. "Impact Assessment Analysis of Sea Level Rise in Denmark: A Case Study of Falster Island, Guldborgsund." Sustainability 13, no. 13 (July 6, 2021): 7503. http://dx.doi.org/10.3390/su13137503.
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Anthropogenically-induced climate change is expected to be the contributing cause of sea level rise and severe storm events in the immediate future. While Danish authorities have downscaled the future oscillation of sea level rise across Danish coast lines in order to empower the coastal municipalities, there is a need to project the local cascading effects on different sectors. Using geospatial analysis and climate change projection data, we developed a proposed workflow to analyze the impacts of sea level rise in the coastal municipalities of Guldborgsund, located in Southeastern Denmark as a case study. With current estimates of sea level rise and storm surge events, the island of Falster can expect to have up to 19% of its landmass inundated, with approximately 39% of the population experiencing sea level rise directly. Developing an analytical workflow can allow stakeholders to understand the extent of expected sea level rise and consider alternative methods of prevention at the national and local levels. The proposed approach along with the choice of data and open source tools can empower other communities at risk of sea level rise to plan their adaptation.
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Seebacher, Frank, Ensiyeh Ghanizadeh Kazerouni, and Craig E. Franklin. "Ultraviolet B radiation alters movement and thermal selection of zebrafish ( Danio rerio )." Biology Letters 12, no. 8 (August 2016): 20160258. http://dx.doi.org/10.1098/rsbl.2016.0258.
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Temperature and ultraviolet B (UV-B) interact in causing cellular damage and impairing locomotor performance. Here, we test the hypothesis that movement and thermal selection of zebrafish ( Danio rerio ) change in the presence of UV-B, and in particular, that fish which were chronically exposed to UV-B avoid high and low temperature extremes to maximize activities of antioxidant enzymes. Fish chronically (two to three weeks) exposed to UV-B had increased reactive oxygen species (ROS)-induced damage to proteins and membranes, and reduced swimming performance at high (more than 26°C) temperatures. In an open field arena with a thermal gradient, chronically exposed fish avoided high and low temperature extremes compared with control fish. Additionally, both control and chronically exposed fish showed slower voluntary swimming speeds in the presence of UV-B. We suggest that in the presence of UV-B fish may reduce muscular activity to minimize intrinsic ROS production. Our data show that the interaction between UV-B and temperature determines movement and microhabitat selection of fish, which is therefore of ecological importance particularly in anthropogenically modified environments.
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Crean, Angela J., and Simone Immler. "Evolutionary consequences of environmental effects on gamete performance." Philosophical Transactions of the Royal Society B: Biological Sciences 376, no. 1826 (April 19, 2021): 20200122. http://dx.doi.org/10.1098/rstb.2020.0122.
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Variation in pre- and post-release gamete environments can influence evolutionary processes by altering fertilization outcomes and offspring traits. It is now widely accepted that offspring inherit epigenetic information from both their mothers and fathers. Genetic and epigenetic alterations to eggs and sperm-acquired post-release may also persist post-fertilization with consequences for offspring developmental success and later-life fitness. In externally fertilizing species, gametes are directly exposed to anthropogenically induced environmental impacts including pollution, ocean acidification and climate change. When fertilization occurs within the female reproductive tract, although gametes are at least partially protected from external environmental variation, the selective environment is likely to vary among females. In both scenarios, gamete traits and selection on gametes can be influenced by environmental conditions such as temperature and pollution as well as intrinsic factors such as male and female reproductive fluids, which may be altered by changes in male and female health and physiology. Here, we highlight some of the pathways through which changes in gamete environments can affect fertilization dynamics, gamete interactions and ultimately offspring fitness. We hope that by drawing attention to this important yet often overlooked source of variation, we will inspire future research into the evolutionary implications of anthropogenic interference of gamete environments including the use of assisted reproductive technologies. This article is part of the theme issue ‘How does epigenetics influence the course of evolution?’
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Lim, Jae-Hyun, and Il-Nam Kim. "Collection of a Bacterial Community Reconstructed from Marine Metagenomes Derived from Jinhae Bay, South Korea." Data 6, no. 5 (April 26, 2021): 44. http://dx.doi.org/10.3390/data6050044.
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Marine bacteria are known to play significant roles in marine biogeochemical cycles regarding the decomposition of organic matter. Despite the increasing attention paid to the study of marine bacteria, research has been too limited to fully elucidate the complex interaction between marine bacterial communities and environmental variables. Jinhae Bay, the study area in this work, is the most anthropogenically eutrophied coastal bay in South Korea, and while its physical and biogeochemical characteristics are well described, less is known about the associated changes in microbial communities. In the present study, we reconstructed a metagenomics data based on the 16S rRNA gene to investigate temporal and vertical changes in microbial communities at three depths (surface, middle, and bottom) during a seven-month period from June to December 2016 at one sampling site (J1) in Jinhae Bay. Of all the bacterial data, Proteobacteria, Bacteroidetes, and Cyanobacteria were predominant from June to November, whereas Firmicutes were predominant in December, especially at the middle and bottom depths. These results show that the composition of the microbial community is strongly associated with temporal changes. Furthermore, the community compositions were markedly different between the surface, middle, and bottom depths in summer, when water column stratification and bottom water hypoxia (low dissolved oxygen level) were strongly developed. Metagenomics data contribute to improving our understanding of important relationships between environmental characteristics and microbial community change in eutrophication-induced and deoxygenated coastal areas.
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Hobson, Keith A., Jackson W. Kusack, and Blanca X. Mora-Alvarez. "Origins of Six Species of Butterflies Migrating through Northeastern Mexico: New Insights from Stable Isotope (δ2H) Analyses and a Call for Documenting Butterfly Migrations." Diversity 13, no. 3 (February 25, 2021): 102. http://dx.doi.org/10.3390/d13030102.
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Determining migratory connectivity within and among diverse taxa is crucial to their conservation. Insect migrations involve millions of individuals and are often spectacular. However, in general, virtually nothing is known about their structure. With anthropogenically induced global change, we risk losing most of these migrations before they are even described. We used stable hydrogen isotope (δ2H) measurements of wings of seven species of butterflies (Libytheana carinenta, Danaus gilippus, Phoebis sennae, Asterocampa leilia, Euptoieta claudia, Euptoieta hegesia, and Zerene cesonia) salvaged as roadkill when migrating in fall through a narrow bottleneck in northeast Mexico. These data were used to depict the probabilistic origins in North America of six species, excluding the largely local E. hegesia. We determined evidence for long-distance migration in four species (L. carinenta, E. claudia, D. glippus, Z. cesonia) and present evidence for panmixia (Z. cesonia), chain (Libytheana carinenta), and leapfrog (Danaus gilippus) migrations in three species. Our investigation underlines the utility of the stable isotope approach to quickly establish migratory origins and connectivity in butterflies and other insect taxa, especially if they can be sampled at migratory bottlenecks. We make the case for a concerted effort to atlas butterfly migrations using the stable isotope approach.
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Qu, Xin, and Alex Hall. "Assessing Snow Albedo Feedback in Simulated Climate Change." Journal of Climate 19, no. 11 (June 1, 2006): 2617–30. http://dx.doi.org/10.1175/jcli3750.1.
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Abstract In this paper, the two factors controlling Northern Hemisphere springtime snow albedo feedback in transient climate change are isolated and quantified based on scenario runs of 17 climate models used in the Intergovernmental Panel on Climate Change Fourth Assessment Report. The first factor is the dependence of planetary albedo on surface albedo, representing the atmosphere's attenuation effect on surface albedo anomalies. It is potentially a major source of divergence in simulations of snow albedo feedback because of large differences in simulated cloud fields in Northern Hemisphere land areas. To calculate the dependence, an analytical model governing planetary albedo was developed. Detailed validations of the analytical model for two of the simulations are shown, version 3 of the Community Climate System Model (CCSM3) and the Geophysical Fluid Dynamics Laboratory global coupled Climate Model 2.0 (CM2.0), demonstrating that it facilitates a highly accurate calculation of the dependence of planetary albedo on surface albedo given readily available simulation output. In all simulations it is found that surface albedo anomalies are attenuated by approximately half in Northern Hemisphere land areas as they are transformed into planetary albedo anomalies. The intermodel standard deviation in the dependence of planetary albedo on surface albedo is surprisingly small, less than 10% of the mean. Moreover, when an observational estimate of this factor is calculated by applying the same method to the satellite-based International Satellite Cloud Climatology Project (ISCCP) data, it is found that most simulations agree with ISCCP values to within about 10%, despite further disagreements between observed and simulated cloud fields. This suggests that even large relative errors in simulated cloud fields do not result in significant error in this factor, enhancing confidence in climate models. The second factor, related exclusively to surface processes, is the change in surface albedo associated with an anthropogenically induced temperature change in Northern Hemisphere land areas. It exhibits much more intermodel variability. The standard deviation is about ⅓ of the mean, with the largest value being approximately 3 times larger than the smallest. Therefore this factor is unquestionably the main source of the large divergence in simulations of snow albedo feedback. To reduce the divergence, attention should be focused on differing parameterizations of snow processes, rather than intermodel variations in the attenuation effect of the atmosphere on surface albedo anomalies.
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Baschek, Burkard, Friedhelm Schroeder, Holger Brix, Rolf Riethmüller, Thomas H. Badewien, Gisbert Breitbach, Bernd Brügge, et al. "The Coastal Observing System for Northern and Arctic Seas (COSYNA)." Ocean Science 13, no. 3 (May 10, 2017): 379–410. http://dx.doi.org/10.5194/os-13-379-2017.
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Abstract. The Coastal Observing System for Northern and Arctic Seas (COSYNA) was established in order to better understand the complex interdisciplinary processes of northern seas and the Arctic coasts in a changing environment. Particular focus is given to the German Bight in the North Sea as a prime example of a heavily used coastal area, and Svalbard as an example of an Arctic coast that is under strong pressure due to global change.The COSYNA automated observing and modelling system is designed to monitor real-time conditions and provide short-term forecasts, data, and data products to help assess the impact of anthropogenically induced change. Observations are carried out by combining satellite and radar remote sensing with various in situ platforms. Novel sensors, instruments, and algorithms are developed to further improve the understanding of the interdisciplinary interactions between physics, biogeochemistry, and the ecology of coastal seas. New modelling and data assimilation techniques are used to integrate observations and models in a quasi-operational system providing descriptions and forecasts of key hydrographic variables. Data and data products are publicly available free of charge and in real time. They are used by multiple interest groups in science, agencies, politics, industry, and the public.
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Barnhill, Kelsey Archer, Nadia Jogee, Colleen Brown, Ashley McGowan, Ku’ulei Rodgers, Ian Bryceson, and Keisha Bahr. "Acclimatization Drives Differences in Reef-Building Coral Calcification Rates." Diversity 12, no. 9 (September 8, 2020): 347. http://dx.doi.org/10.3390/d12090347.
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Coral reefs are susceptible to climate change, anthropogenic influence, and environmental stressors. However, corals in Kāneʻohe Bay, Hawaiʻi have repeatedly shown resilience and acclimatization to anthropogenically-induced rising temperatures and increased frequencies of bleaching events. Variations in coral and algae cover at two sites—just 600 m apart—at Malaukaʻa fringing reef suggest genetic or environmental differences in coral resilience between sites. A reciprocal transplant experiment was conducted to determine if calcification (linear extension and dry skeletal weight) for dominant reef-building species, Montipora capitata and Porites compressa, varied between the two sites and whether or not parent colony or environmental factors were responsible for the differences. Despite the two sites representing distinct environmental conditions with significant differences between temperature, salinity, and aragonite saturation, M. capitata growth rates remained the same between sites and treatments. However, dry skeletal weight increases in P. compressa were significantly different between sites, but not across treatments, with linear mixed effects model results suggesting heterogeneity driven by environmental differences between sites and the parent colonies. These results provide evidence of resilience and acclimatization for M. capitata and P. compressa. Variability of resilience may be driven by local adaptations at a small, reef-level scale for P. compressa in Kāneʻohe Bay.
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Wagner, S., I. Fast, and F. Kaspar. "Comparison of 20th century and pre-industrial climate over South America in regional model simulations." Climate of the Past 8, no. 5 (October 16, 2012): 1599–620. http://dx.doi.org/10.5194/cp-8-1599-2012.
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Abstract. In this study, we assess how the anthropogenically induced increase in greenhouse gas concentrations affects the climate of central and southern South America. We utilise two regional climate simulations for present day (PD) and pre-industrial (PI) times. These simulations are compared to historical reconstructions in order to investigate the driving processes responsible for climatic changes between the different periods. The regional climate model is validated against observations for both re-analysis data and GCM-driven regional simulations for the second half of the 20th century. Model biases are also taken into account for the interpretation of the model results. The added value of the regional simulation over global-scale modelling relates to a better representation of hydrological processes that are particularly evident in the proximity of the Andes Mountains. Climatic differences between the simulated PD minus PI period agree qualitatively well with proxy-based temperature reconstructions, albeit the regional model overestimates the amplitude of the temperature increase. For precipitation the most important changes between the PD and PI simulation relate to a dipole pattern along the Andes Mountains with increased precipitation over the southern parts and reduced precipitation over the central parts. Here only a few regions show robust similarity with studies based on empirical evidence. However, from a dynamical point-of-view, atmospheric circulation changes related to an increase in high-latitude zonal wind speed simulated by the regional climate model are consistent with numerical modelling studies addressing changes in greenhouse gas concentrations. Our results indicate that besides the direct effect of greenhouse gas changes, large-scale changes in atmospheric circulation and sea surface temperatures also exert an influence on temperature and precipitation changes in southern South America. These combined changes in turn affect the relationship between climate and atmospheric circulation between PD and PI times and should be considered for the statistical reconstruction of climate indices calibrated within present-day climate data.
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Xue, Yayong, Baoqing Zhang, Chansheng He, and Rui Shao. "Detecting Vegetation Variations and Main Drivers over the Agropastoral Ecotone of Northern China through the Ensemble Empirical Mode Decomposition Method." Remote Sensing 11, no. 16 (August 9, 2019): 1860. http://dx.doi.org/10.3390/rs11161860.
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Vegetation is the major component of the terrestrial ecosystem. Understanding both climate change and anthropogenically induced vegetation variation is essential for ecosystem management. In this study, we used an ensemble empirical mode decomposition (EEMD) method and a linear regression model to investigate spatiotemporal variations in the normalized difference vegetation index (NDVI) over the agropastoral ecotone of northern China (APENC) during the 1982–2015 period. A quantitative approach was proposed based on the residual trend (RESTREND) method to distinguish the effects of climatic (i.e., temperature (TEM), precipitation (PRE), total downward solar radiation (RAD), and near surface wind speed (SWS)) and anthropogenic effects on vegetation variations. The results showed that the NDVI exhibited a significant greening trend of 0.002 year−1 over the entire study period of 1982–2015 and that areas with monotonous greening dominated the entire APENC, occupying 40.97% of the region. A browning trend was also found in the central and northern parts of the APENC. PRE presented the highest spatial correlation with the NDVI and climate factors, suggesting that PRE was the most important factor affecting NDVI changes in the study area. In addition, the RESTREND results indicated that anthropogenic contributions dominated the vegetation variations in the APENC. Therefore, reusing farmland for grass and tree planting made a positive contribution to vegetation restoration, while deforestation, overgrazing, and the reclamation of grasslands were the opposite. In addition, with the continuous implementation of national ecological engineering programs such as the Grain to Green Program, positive human activity contributions to vegetation greening significantly increased. These results will support decision- and policy-making in the assessment and rehabilitation of ecosystems in the study region.
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Porinchu, David F., and Glen M. MacDonald. "The use and application of freshwater midges (Chironomidae: Insecta: Diptera) in geographical research." Progress in Physical Geography: Earth and Environment 27, no. 3 (September 2003): 378–422. http://dx.doi.org/10.1191/0309133303pp388ra.
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The potential of applying the analysis of freshwater midges (Chironomidae) for current questions in geographical research is examined. Chironomids are cosmopolitan in distribution and frequently the most abundant insects found in freshwater ecosystems. The capacity of the family to tolerate large gradients of pH, salinity, depth, oxygen concentration, temperature and productivity enables members of the Chironomidae to occupy virtually every available niche present in freshwater environments. In addition to wide distribution and abundance, Chironomidae are well suited for paleolimnological studies because the larvae possess chitinous head capsules which are well-preserved in lake sediment and relatively easily recovered and identified. As a result, chironomids are increasingly being used to track a number of natural and anthropogenically induced limnological changes resulting from atmospheric contamination, eutrophication and increased lake water salinity. Other areas in which subfossil chironomid analysis has provided valuable insight include climate change, phylogentics and biogeography and aquatic ecosystem dynamics and development. Details describing the biology and ecology of the Chironomidae that are directly relevant to their use in paleoenvironmental and biogeographical studies are presented. The methodology describing the recovery and identification of subfossil chironomid remains is reviewed. A generalized overview of the statistical methods that are commonly employed in relating the modern distribution of chironomids to specific aspects of the environment, i.e., the calibration dataset approach, is briefly discussed. Case studies that highlight the various uses and applications of chironomid analysis in areas of paleoenvironmental and biogeographical research relevant to geographers are described. Lastly, the current status of chironomid research in academic geography is discussed and suggestions of potential future research directions are made.
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Schneiderhan-Opel, Jennifer, and Franz X. Bogner. "Cannot See the Forest for the Trees? Comparing Learning Outcomes of a Field Trip vs. a Classroom Approach." Forests 12, no. 9 (September 16, 2021): 1265. http://dx.doi.org/10.3390/f12091265.
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Anthropogenically induced environmental changes, such as the persistent loss of biodiversity and decline in global forest stocks, require comprehensive, societal change towards sustainable behavior. Education is considered the key to empowering sustainable decision-making, cooperative participation, high levels of commitment, and motivation to support environmental protection. Holistic Education for Sustainable Development (ESD) approaches aim to foster eco-friendly behavior by combining knowledge acquisition with the promotion of affective drivers. The present study focuses on monitoring the individual interplay between ecological knowledge and environmental values. We compared learning outcomes within two environments: a nature-based, out-of-school setting at a local forest (study 1) and a classroom setting (study 2). Overall, 444 German 7th grade students participated in learner-centered activities on the topic of the forest ecosystem under anthropogenic influences. Following a quasi-experimental study design, we monitored pro-environmental and anthropogenic values (Preservation and Utilization) and knowledge at three test times: before (T1), directly after (T1) and six weeks after (T2) participation in the learning program. Students in both treatments acquired short- and long-term environmental knowledge regardless of the learning environment but in neither case did the learning activities intervene with individual environmental values. However, Preservation showed a positive correlation with the mean knowledge scores in both studies, while for Utilization, this relationship was reversed. A comparison of extreme groups revealed that, in both treatment groups, students with high pro-environmental values and low anthropogenic values showed a significantly better performance than their counterparts. Our findings highlight the importance of monitoring pro-environmental values when preparing educational modules for student groups independent from the learning environment.
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Graham, Russell W. "Response of North American mammal communities to late Quaternary environmental fluctuations." Paleontological Society Special Publications 6 (1992): 112. http://dx.doi.org/10.1017/s2475262200006729.
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The late Quaternary was a time of rapid environmental fluctuations. The last glacial maximum was reached about 20 ka with continental glaciers covering most of Canada as well as the northeastern and upper midwestern United States (U.S.). Glacial ice physically displaced entire terrestrial biomes and the cooler climates altered distributions of species outside of the glacial limits. About 14 ka, the climate began to warm rapidly and glacial ice retreated northward, opening new landscapes for colonization by terrestrial biotas. Maximum warmth was reached between 9–5 ka with a time transgressive progression from west to east.Radiocarbon chronologies allow for fine scale (100's to 1000's of years) resolution of mammal responses to these changes. Mammal communities did not respond as intact units but individual species shifted diachronically along environmental gradients. As a result, many late Pleistocene mammal communities contain associations of extant species that do not occur together today and appear to be ecologically incompatible. Pleistocene mammal communities also had a greater diversity of species than either Holocene or modern ones. This greater diversity was, in part, due to the existence of a diverse megafauna that became extinct at the end of the Pleistocene (10 ka). However, Pleistocene small mammal guilds with extant species, especially insectivores and microtine rodents, were also more diverse. Rapid changes in small mammal species distributions, diversity patterns, and clinal shifts around 10 ka strengthens environmental models for the end-Pleistocene extinction.Modern mammal communities began to appear at the end of the Pleistocene and into the Holocene. In the eastern U.S., the species composition of these communities has been stable for the last 10 ka, although vegetational communities have shown change throughout the Holocene. In other parts of the U.S., middle Holocene warming caused some species to shift their geographic ranges. However, species composition of communities was not significantly altered. Understanding these changes not only provides a better perspective for viewing mammal communities of the past but it may also give insight into those of the future as climate will continue to vacillate, whether induced naturally or anthropogenically.
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Vikrant, Kumar, Eilhann E. Kwon, Ki-Hyun Kim, Christian Sonne, Minsung Kang, and Zang-Ho Shon. "Air Pollution and Its Association with the Greenland Ice Sheet Melt." Sustainability 13, no. 1 (December 23, 2020): 65. http://dx.doi.org/10.3390/su13010065.
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The Greenland Ice Sheet (GrIS) has been a topic of extensive scientific research over the past several decades due to the exponential increase in its melting. The relationship between air pollution and GrIS melting was reviewed based on local emission of air pollutants, atmospheric circulation, natural and anthropogenic forcing, and ground/satellite-based measurements. Among multiple factors responsible for accelerated ice melting, greenhouse gases have long been thought to be the main reason. However, it is suggested that air pollution is another piece of the puzzle for this phenomenon. In particular, black carbon (BC) and other aerosols emitted anthropogenically interact with clouds and ice in the Arctic hemisphere to shorten the cloud lifespan and to change the surface albedo through alteration of the radiative balance. The presence of pollution plumes lowers the extent of super cooling required for cloud freezing by about 4 °C, while shortening the lifespan of clouds (e.g., by altering their free-energy barrier to prompt precipitation). Since the low-level clouds in the Arctic are 2–8 times more sensitive to air pollution (in terms of the radiative/microphysical properties) than other regions in the world, the melting of the GrIS can be stimulated by the reduction in cloud stability induced by air pollution. In this study, we reviewed the possible impact of air pollution on the melting of the GrIS in relation to meteorological processes and emission of light-absorbing impurities. Long-term variation of ground-based AERONET aerosol optical depth in Greenland supports the potential significance of local emission and long-range transport of air pollutants from Arctic circle and continents in the northern hemisphere in rapid GrIS melting trend.
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Williams, W. D. "Environmental threats to salt lakes and the likely status of inland saline ecosystems in 2025." Environmental Conservation 29, no. 2 (June 2002): 154–67. http://dx.doi.org/10.1017/s0376892902000103.
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Salt lakes are geographically widespread, numerous and a significant part of the world's inland aquatic ecosystems. They are important natural assets with considerable aesthetic, cultural, economic, recreational, scientific, conservation and ecological values. Some features, notably the composition of the biota, uniquely distinguish them from other aquatic ecosystems. The paper reviews the nature of environmental impacts and their effects upon salt lakes. Its aims are two-fold: to draw attention to the extensive damage that salt lakes have now undergone, and to indicate the likely status of salt lakes in 2025. Salt lakes develop as the termini of inland drainage basins where hydrological inputs and outputs are balanced. These conditions occur in arid and semi-arid regions (approximately one-third of total world land area). Many human activities threaten or have already impacted salt lakes, especially surface inflow diversions, salinization and other catchment activities, mining, pollution, biological disturbances (e.g. introduction of exotic species), and anthropogenically-induced climatic and atmospheric changes. The effects of such activities are always adverse and include changes to the natural character of salt lakes, loss of biodiversity and fundamental limnological changes. The effects are geographically widespread, mostly irreversible, and degrade the values of salt lakes. Four salt lakes are discussed, namely the Aral Sea in central Asia, Mono Lake in California, USA, and Lake Eyre and Lake Cantara South, in Australia. By 2025, most natural salt lakes will have undergone some adverse change. Many permanent ones will have decreased in size and increased in salinity, and many unnatural saline water-bodies will have appeared. In certain regions, many seasonally-filled salt lakes are likely to be drier for longer periods. The extent to which episodically-filled salt lakes will change by 2025 will largely depend upon the nature of climate change in arid regions. Objective cost/benefit analyses of adversely affecting salt lakes are rare, and international bodies have not properly recognized salt lakes as important inland aquatic ecosystems. To redress this situation, there is a need to raise awareness of: (1) the values of salt lakes, (2) the nature of threats and impacts from human activities, and (3) their special management requirements. More effective management and conservation measures need to be implemented. Mono Lake provides an example of what can be achieved in the conservation of salt lakes. Its conservation was largely brought about by (1) the commitment of a non-governmental organization which recognized its non-economic values, (2) the freedom to express views, (3) a legal system which took account of non-economic values, and (4) a legislature which implemented judicial findings. The conservation of Mono Lake was difficult; the conservation of other salt lakes is likely to be even more difficult. Only international pressure from appropriate organizations will be effective for the conservation of many.
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Li, Cong, Xumao Zhao, Dayong Li, Paul Alan Garber, Zuofu Xiang, Ming Li, and Huijuan Pan. "Impact of cost distance and habitat fragmentation on the daily path length of Rhinopithecus bieti." PeerJ 8 (May 20, 2020): e9165. http://dx.doi.org/10.7717/peerj.9165.
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An understanding of primate movement patterns in response to natural and anthropogenically induced changes in habitat heterogeneity, food availability, and plant species distribution is essential for developing effective management and conservation programs. Therefore, from July 2013 to June 2014, we examined the effects of landscape configuration on the ranging behavior (daily path length, DPL) of the Endangered Yunnan snub-nosed monkey (Rhinopithecus bieti) in the Baimaxueshan National Nature Reserve (27°34′N, 99°17′E) in Gehuaqing, China. Given the extreme difficulties in following the study group across high altitude mountainous terrain across an elevation of 2,500–4,000 m, we were only able to collect DPL using 3-4 GPS points per day on 21 individual days. We found that R. bieti traveled the shortest DPL in winter (1,141.31 m), followed by spring (2,034.06 m) and autumn (2,131.19 m). The cost distance, a statistical tool designed to estimate the difficulty of a species moving across its distributional range, was lowest in autumn (205.47), followed by spring (225.93) and winter (432.59) (one-way ANOVA: F = 3.852, P = 0.026, df = 2). The habitat fragmentation index (HFI), which measures the density of forest patches, indicated areas visited in the winter were more fragmented (HFI = 2.16) compared to spring (HFI = 1.83) or autumn (HFI = 1.3). Although our results should be considered preliminary, they suggest that both the availability of suitable travel routes and habitat fragmentation, driven by high-intensity human disturbance, constrain the movement of R. bieti. We found that undisturbed areas of the bands’ range contained a high density of lichens, which represent a nutritious and abundant and year-round food source for Yunnan snub-nosed monkeys. In order to protect this Endangered species, we recommend that researchers construct detailed maps of landscape heterogeneity, particularly habitat connectivity, forest fragmentation, and seasonal variation in the location of major food patches in order to better understand and mitigate the effects of seasonal habitat change on patterns of R. bieti habitat utilization and population viability.
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Fodrie, F. J., L. A. Levin, and A. E. Rathburn. "High densities and depth-associated changes of epibenthic megafauna along the Aleutian margin from 2000–4200 m." Journal of the Marine Biological Association of the United Kingdom 89, no. 8 (July 9, 2009): 1517–27. http://dx.doi.org/10.1017/s0025315409000903.
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The Aleutian margin is a dynamic environment underlying a productive coastal ocean and subject to frequent tectonic disturbance. In July 2004, we used over 500 individual bottom images from towed camera transects to investigate patterns of epibenthic megafaunal density and community composition on the contiguous Aleutian margin (53°N 163°W) at depths of 2000 m, 3200 m and 4200 m. We also examined the influence of vertical isolation on the megafaunal assemblage across a topographic rise at 3200 m, located 30 km from the main margin and elevated 800 m above the surrounding seafloor. In comparison to previous reports from bathyal and abyssal depths, megafaunal densities along the Aleutian margin were remarkably high, averaging 5.38±0.43 (mean±1 standard error), 0.32±0.02 to 0.43±0.03 and 0.27±0.01 individuals m−2 at 2000 m, 3200 m and 4200 m, respectively. Diversity at 2000 m was elevated by 15–30% over the deeper sites (3200–4200 m) depending on the metric, while evenness was depressed by ~10%. Levels of richness and evenness were similar among the three deeper sites. Echinoderms were the most abundant phylum at each depth; ophiuroids accounted for 89% of individuals in photographs at 2000 m, echinoids were dominant at 3200 m (39%), and holothurians dominated at 4200 m (47%). We observed a 26% reduction in megafaunal density across the summit of the topographic rise relative to that documented on the continental slope at the same depth. However, the two communities at 3200 m were very similar in composition. Together, these data support the modified ‘archibenthal zone of transition’ framework for slope community patterns with distinct communities along the middle and lower slope (the upper slope was not evaluated here). This study fills a geographical gap by providing baseline information for a relatively pristine, high-latitude, deep-sea benthic ecosystem. As pressures grow for drilling, fishing and mining on high-latitude margins, such data can serve as a reference point for much-needed studies on the ecology, long-term dynamics, and anthropogenically induced change of these habitats.
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Ernst, Raffael, and Mark-Oliver Rödel. "ANTHROPOGENICALLY INDUCED CHANGES OF PREDICTABILITY IN TROPICAL ANURAN ASSEMBLAGES." Ecology 86, no. 11 (November 2005): 3111–18. http://dx.doi.org/10.1890/04-0800.
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Tsidu, G. Mengistu. "High-Resolution Monthly Rainfall Database for Ethiopia: Homogenization, Reconstruction, and Gridding." Journal of Climate 25, no. 24 (December 15, 2012): 8422–43. http://dx.doi.org/10.1175/jcli-d-12-00027.1.
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Abstract Recent heightened concern regarding possible consequences of anthropogenically induced global warming has spurred analyses of data aimed at detection of climate change and more thorough characterization of the natural climate variability. However, there is greater concern regarding the extent and especially quality of the historical climate data. In this paper, rainfall records of 233 gauge stations over Ethiopia for the 1978–2007 period are employed in an analysis that involves homogenization, reconstruction, and gridding onto a regular 0.5° × 0.5° resolution grid. Inhomogeneity is detected and adjusted based on quantile matching. The regularized expectation-maximization and multichannel singular spectrum analysis algorithms are then utilized for imputation of missing values, and the latter has been determined to have a marginal advantage. Ordinary kriging is used to create a gridded monthly rainfall dataset. The spatial and temporal coherence of this dataset are assessed using harmonic analysis, self-organizing maps, and intercomparison with global datasets. The self-organizing map delineates Ethiopia into nine homogeneous rainfall regimes, which is consistent with seasonal and interannual rainfall variations. The harmonic analysis of the dataset reveals that the annual mode accounts for 55%–85% of the seasonal rainfall variability over western Ethiopia while the semiannual mode accounts for up to 40% over southern Ethiopia. The dataset is also intercompared with Global Precipitation Climatology Project (GPCP), Climate Prediction Center (CPC) Merged Analysis of Precipitation (CMAP), Climatic Research Unit time series version 3 (CRUTS3.0), Tropical Rainfall Measuring Mission (TRMM), and interim ECMWF Re-Analysis (ERA-Interim) rainfall. The correlation of the dataset with global datasets ranges from 0.52 to 0.95 over sparse to dense rain gauge regions. The GPCP rainfall has a small bias and good correlation with the new dataset whereas TRMM and ERA-Interim have relatively large dry and wet biases, respectively.
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Hommel, R., K. U. Eichmann, J. Aschmann, K. Bramstedt, M. Weber, C. von Savigny, A. Richter, et al. "Chemical composition and severe ozone loss derived from SCIAMACHY and GOME-2 observations during Arctic winter 2010/2011 in comparisons to Arctic winters in the past." Atmospheric Chemistry and Physics Discussions 13, no. 6 (June 20, 2013): 16597–660. http://dx.doi.org/10.5194/acpd-13-16597-2013.
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Abstract. Record breaking losses of ozone (O3) in the Arctic stratosphere have been reported in winter and spring 2011. Trace gas amounts and polar stratospheric cloud (PSC) distributions retrieved using differential optical absorption spectroscopy (DOAS) and scattering theory applied to the measurements of radiance and irradiance by satellite-born and ground-based instrumentation, document the unusual behaviour. A chemical transport model has been used to relate and compare Arctic winter-spring conditions in 2011 with those in previous years. We examine in detail the composition and transformations occurring in the Arctic polar vortex using total column and vertical profile data products for O3, bromine oxide (BrO), nitrogen dioxide (NO2), chlorine dioxide (OClO), and PSCs retrieved from measurements made by the instrument SCIAMACHY onboard the ESA satellite Envisat, as well as the total column ozone amount, retrieved from the measurements of GOME-2 on the EUMETSAT operational meteorological polar orbiter Metop-A. In the late winter and spring 2010/2011 the chemical loss of O3 in the polar vortex is consistent with and confirms findings reported elsewhere. More than 70% of O3 was depleted between the 425 K and 525 K isentropic surfaces, i.e. in the altitude range ~16–20 km. In contrast, during the same period in the previous winter only slightly more than 20% depletion occurred below 20 km, whereas 40% of the O3 was removed above the 575 K isentrope (~23 km). This loss above the 575 K isentrope is explained by the catalytic destruction by the NOx descending from the mesosphere. At lower altitudes O3 loss results from processing by halogen driven O3 catalytic removal cycles, activated by the large volume of PSC generated throughout this winter and spring. The mid-winter 2011 conditions, prior to the catalytic cycles being fully effective, are also investigated. Surprisingly, a significant loss of O3 with 60% is observed in mid-January 2011 below 500 K (~19 km), which was then sustained for approximately a week. This "mini-hole" event had an exceptionally large spatial extent. Such meteorologically driven changes in polar stratospheric O3 are expected to increase in frequency as anthropogenically induced climate change evolves.
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Colman, Steven M., and John F. Bratton. "Anthropogenically induced changes in sediment and biogenic silica fluxes in Chesapeake Bay." Geology 31, no. 1 (2003): 71. http://dx.doi.org/10.1130/0091-7613(2003)031<0071:aicisa>2.0.co;2.
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Berger-Tal, Oded, and David Saltz. "Invisible barriers: anthropogenic impacts on inter- and intra-specific interactions as drivers of landscape-independent fragmentation." Philosophical Transactions of the Royal Society B: Biological Sciences 374, no. 1781 (July 29, 2019): 20180049. http://dx.doi.org/10.1098/rstb.2018.0049.
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Anthropogenically induced fragmentation constitutes a major threat to biodiversity. Presently, conservation research and actions focus predominantly on fragmentation caused directly by physical transformation of the landscape (e.g. deforestation, agriculture, urbanization, roads, etc.). While there is no doubt that landscape features play a key role in fragmenting populations or enhancing connectivity, fragmentation may also come about by processes other than the transformation of the landscape and which may not be readily visible. Such landscape-independent fragmentation (LIF) usually comes about when anthropogenic disturbance alters the inter- and intra-specific interactions among and within species. LIF and its drivers have received little attention in the scientific literature and in the management of wildlife populations. We discuss three major classes of LIF processes and their relevance for the conservation and management of species and habitats: (i) interspecific dispersal dependency, in which populations of species that rely on other species for transport and propagation become fragmented as the transporting species declines; (ii) interspecific avoidance induction, where species are excluded from habitats and corridors owing to interspecific interactions resulting from anthropogenically induced changes in community structure (e.g. exclusions by increased predation pressure); and (iii) intraspecific behavioural divergence, where populations become segregated owing to anthropogenically induced behavioural differentiation among them. This article is part of the theme issue ‘Linking behaviour to dynamics of populations and communities: application of novel approaches in behavioural ecology to conservation'.
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Taft, Linda, and Mariele Evers. "A review of current and possible future human–water dynamics in Myanmar's river basins." Hydrology and Earth System Sciences 20, no. 12 (December 15, 2016): 4913–28. http://dx.doi.org/10.5194/hess-20-4913-2016.
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Abstract. Rivers provide a large number of ecosystem services and riparian people depend directly and indirectly on water availability and quality and quantity of the river waters. The country's economy and the people's well-being and income, particularly in agriculturally dominated countries, are strongly determined by the availability of sufficient water. This is particularly true for the country of Myanmar in South-east Asia, where more than 65 % of the population live in rural areas, working in the agricultural sector. Only a few studies exist on river basins in Myanmar at all and detailed knowledge providing the basis for human–water research is very limited. A deeper understanding of human–water system dynamics in the country is required because Myanmar's society, economy, ecosystems and water resources are facing major challenges due to political and economic reforms and massive and rapid investments from neighbouring countries. However, not only policy and economy modify the need for water. Climate variability and change are other essential drivers within human–water systems. Myanmar's climate is influenced by the Indian Monsoon circulation which is subject to interannual and also regional variability. Particularly the central dry zone and the Ayeyarwady delta are prone to extreme events such as serious drought periods and extreme floods. On the one hand, the farmers depend on the natural fertiliser brought by regular river inundations and high groundwater levels for irrigation; on the other hand, they suffer from these water-related extreme events. It is expected that theses climatic extreme events will likely increase in frequency and magnitude in the future as a result of global climate change. Different national and international interests in the abundant water resources may provide opportunities and risks at the same time for Myanmar. Several dam projects along the main courses of the rivers are currently in the planning phase. Dams will most likely modify the river flows, the sediment loads and also the still rich biodiversity in the river basins, to an unknown extent. Probably, these natural and anthropogenically induced developments will also impact a special type of farming; we call it alluvial farming in the river floodplains and on sandbars in the Ayeyarwady River basin in Myanmar, which is called Kaing and Kyun, respectively. Relevant aspects for future development of Myanmar's river basins combine environment-water-related factors, climate, economic and social development, water management and land use changes. Research on these interplays needs to capture the spatial and temporal dynamics of these drivers. However, it is only possible to gain a full understanding of all these complex interrelationships if multi-scale spatiotemporal information is analysed in an inter- and trans-disciplinary approach. This paper gives a structured overview of the current scientific knowledge available and reveals the relevance of this information with regard to human–environment and particularly to human–water interactions in Myanmar's river basins. By applying the eDPSIR framework, it identifies key indicators in the Myanmar human–water system, which has been shown to be exemplary by giving an example of use related to alluvial farming in the central dry zone.