Artykuły w czasopismach na temat „Ecological disturbance”
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Dornelas, Maria. "Disturbance and change in biodiversity". Philosophical Transactions of the Royal Society B: Biological Sciences 365, nr 1558 (27.11.2010): 3719–27. http://dx.doi.org/10.1098/rstb.2010.0295.
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Understanding how disturbance affects biodiversity is important for both fundamental and applied reasons. Here, I investigate how disturbances with different ecological effects change biodiversity metrics. I define three main types of disturbance effects: D disturbance (shifts in mortality rate), B disturbance (shifts in reproductive rates) and K disturbance (shifts in carrying capacity). Numerous composite disturbances can be defined including any combination of these three types of ecological effects. The consequences of D , B and K disturbances, as well as of composite DBK disturbances are examined by comparing metrics before and after a disturbance, in disturbed and undisturbed communities. I use simulations of neutral communities and examine species richness, total abundance and species abundance distributions. The patterns of change in biodiversity metrics are consistent among different types of disturbance. K disturbance has the most severe effects, followed by D disturbance, and B disturbance has nearly negligible effects. Consequences of composite DBK disturbances are more complex than any of the three types of disturbance, with unimodal relationships along a disturbance gradient arising when D, B and K are negatively correlated. Importantly, regardless of disturbance type, community isolation enhances the negative consequences and hinders the positive effects of disturbances.
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Crausbay, Shelley D., i Patrick H. Martin. "Natural disturbance, vegetation patterns and ecological dynamics in tropical montane forests". Journal of Tropical Ecology 32, nr 5 (14.07.2016): 384–403. http://dx.doi.org/10.1017/s0266467416000328.
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Abstract:Disturbance is a central process in forest dynamics, yet the role of natural disturbance in tropical montane forests (TMFs) has not been systematically addressed. We posit that disturbance in TMFs has a wider role than commonly acknowledged and its effects are distinctive because: (1) TMFs often have very low rates of productivity due to low resources, and so recovery from disturbance may be slow, (2) montane forests have marked environmental heterogeneity which interacts with disturbance, (3) a large percentage of TMFs are regularly exposed to high energy windstorms and landslides, and (4) TMFs contain a biogeographically rich mixture of tree species with divergent evolutionary histories that interact differently with different disturbance types. We reviewed the literature on natural disturbance in TMFs and found 119 peer-reviewed papers which met our search criteria. Our review shows that disturbance is widespread in TMFs with pronounced effects on structure, function, composition and dynamics. Disturbance is also evident in the ecology of TMF biota with clear examples of plant life-history traits adapted to disturbance, including disturbance-triggered germination, treefall gap strategies and resprouting ability. Important aspects of TMF disturbances are stochastic and site-specific, but there are broad patterns in disturbance type, frequency and severity along latitudinal, altitudinal and environmental gradients. Compared with the lowland tropics, TMF disturbances are more spatially structured, TMFs experience more disturbance types in a given area due to environmental complexity, and TMFs are much more prone to small-scale yet severe landslides as well the large and potentially catastrophic disturbances of cyclones, forest die-back and fire. On the whole, natural disturbance should assume a larger role in models of ecosystem processes and vegetation patterns in TMFs. An improved understanding of what creates variation in disturbance severity and post-disturbance recovery rates, how composition and diversity feedback on disturbance type and likelihood, and how global change will alter these dynamics are important priorities in future TMF ecology research.
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Lugo, Ariel E. "Effects of Extreme Disturbance Events: From Ecesis to Social–Ecological–Technological Systems". Ecosystems 23, nr 8 (18.02.2020): 1726–47. http://dx.doi.org/10.1007/s10021-020-00491-x.
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AbstractEcologists addressed the effects of disturbances from the onset of the field by focusing on ecesis, which is the process by which organisms migrate and establish under the environmental conditions created by disturbances. Ecesis is the onset of succession, a self-organizing process whose nature, speed, and outcome depend in part on the outcomes of ecesis and the residual legacies remaining after disturbances. A by-product of succession after a disturbance is the reorganization of species dominance, or novelty. The degree of novelty in the outcome increases with the severity of the disturbance event. Initially, ecologists focused mostly on non-anthropogenic disturbances, but as human activity intensified and became a global force, more attention was given to the effects of anthropogenic disturbances on ecosystems. Today, anthropogenic and non-anthropogenic disturbances and their interactions are increasingly affecting ecosystems, particularly those exposed to extreme disturbance events. Extreme disturbance events are complex and low probability events composed of several disturbance forces that individually and in synergy affect different sectors of ecosystems, including the conditions that drive ecesis. I review the literature on disturbance research including the effects of extreme disturbance events on social–ecological–technological systems (SETSs). A SETS is an ecosystem defined by the flow and accumulation of energy through the medium of organisms, constructed infrastructure, institutions, and their environment. Human intentions, values, and capacities are part of the functioning of SETS, and they can drive ecological processes as do non-anthropogenic forces. Moreover, human-directed activities after an extreme disturbance event affect whole landscapes. The passage of hurricane María over the Puerto Rico SETS established that extreme disturbance events are of such power and complexity that they can influence the level and kind of relationship between humans and the environment, including the structure and species composition of the ecological systems within SETS. However, extreme disturbance events such as hurricanes have not changed the successional trajectory originally impulsed by anthropogenic disturbances. Thus, the species composition and functioning of novel forests in Puerto Rico are tied to economic activity in the social and technological sectors of SETS. It is no longer possible to interpret ecosystem functioning without considering the synergy between anthropogenic and non-anthropogenic extreme disturbances.
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Halling, Roy E., L. Boddy, R. Watling i A. J. E. Lyon. "Fungi and Ecological Disturbance". Mycologia 81, nr 5 (wrzesień 1989): 826. http://dx.doi.org/10.2307/3759894.
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Zhang, H., Z. Zhang, X. Guo, J. Zhao i Y. Shan. "UNDERSTANDING THE SPATIO-TEMPORAL PATTERN OF FIRE DISTURBANCE IN THE EASTERN MONGOLIA USING MODIS PRODUCT". ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLII-3 (30.04.2018): 1921–24. http://dx.doi.org/10.5194/isprs-archives-xlii-3-1921-2018.
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Fire disturbance plays an important role in maintaining ecological balance, biodiversity and self-renewal. In this paper, the spatio-temporal pattern of fire disturbances in eastern Mongolia are studied by using the ArcGIS spatial analysis method, using the MCD45A1 data of MODIS fire products with long time series. It provides scientific basis and reference for the regional ecological environment security construction and international ecological security. Research indicates: (1) The fire disturbance in eastern Mongolia has obvious high and low peak interleaving phenomenon in the year, and the seasonal change is obvious. (2) The distribution pattern of fire disturbance in eastern Mongolia is aggregated, which indicates that the fire disturbance is not random and it is caused by certain influence. (3) Fire disturbance is mainly distributed in the eastern province of Mongolia, the border between China and Mongolia and the northern forest area of Sukhbaatar province. (4) The fire disturbance in the eastern part of the study area is strong and the southwest is weaker. The spreading regularity of fire disturbances in eastern Mongolia is closer to the natural level of ecosystem.
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Edwards, Patrick M., Megan Colley i Angie Shroufe. "Investigating Ecological Disturbance in Streams". American Biology Teacher 83, nr 4 (1.04.2021): 254–62. http://dx.doi.org/10.1525/abt.2021.83.4.254.
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Teaching students about ecological disturbance provides them with an understanding of a critical factor that shapes the structure and function of biological communities in environmental systems. This article describes four simple experiments and related curriculum that students can use to conduct inquiry around the theme of disturbance in stream ecosystems: insect drift, colonization, life history, and the intermediate disturbance hypothesis. Over five years, our students conducted these experiments 57 times; 79% of the experiments resulted in data that supported students’ hypotheses. Our findings show that the experiments can be used as a framework for inquiry-based learning about important ecological processes such as disturbance, dispersal, colonization, and succession. These experiments meet several of the Next Generation Science Standards, are easily and ethically conducted, and require very little equipment.
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Savage, Melissa. "Ecological Disturbance and Nature Tourism". Geographical Review 83, nr 3 (lipiec 1993): 290. http://dx.doi.org/10.2307/215731.
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DeAngelis, D. L., J. C. Waterhouse, W. M. Post i R. V. O'Neill. "Ecological modelling and disturbance evaluation". Ecological Modelling 29, nr 1-4 (wrzesień 1985): 399–419. http://dx.doi.org/10.1016/0304-3800(85)90063-8.
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Hu, Yang, Tim S. Doherty i Tim S. Jessop. "How influential are squamate reptile traits in explaining population responses to environmental disturbances?" Wildlife Research 47, nr 3 (2020): 249. http://dx.doi.org/10.1071/wr19064.
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Abstract Context Understanding how organismal attributes influence sensitivity to environmental perturbations is a central theme in ecology and conservation. Certain traits, such as body size, habitat use, dietary preference and reproductive output are considered important determinants of animal species’ responses to the impacts of ecological disturbances. However, the general relationships between functional traits and post-disturbance responses by animals are not fully understood. AimsOur primary aim was to use a meta-analysis to evaluate the influence of species traits on variation in population abundances of squamate reptiles (i.e. lizards and snakes). MethodsWe extracted data from 107 original published studies, from which 1027 mean effect sizes of post-disturbance responses by 298 species were estimated. We examined short-term responses only (i.e. within 3 years since the most recent disturbance). A comprehensive range of disturbances was examined, such as habitat destruction, fragmentation, fire, and exotic-species invasions. We used Bayesian linear mixed-effect modelling (BLMM), utilising the Markov-chain Monte Carlo algorithm (MCMC) for the meta-regression. Specifically, we tested the influence of eight species traits (body size, diet, temporal activity pattern, sociality, reproductive mode, clutch size, habitat selection, and mean body temperature), along with disturbance type, in explaining variation in species-specific abundance responses of squamate reptiles post-disturbance. Key resultsPost-disturbance abundance responses of squamate species were significantly influenced by two parameters, namely, mean body temperature and clutch size. In general, significant positive responses post-disturbance were observed for species with higher mean body temperatures and a greater clutch size. The type of disturbance had no detectable influence on squamate abundances. The influence of random effects (heterogeneity among studies and species, and broad taxonomic identity) accounted for more of the model variation than did the fixed effects (species traits and disturbance type). ConclusionsCertain species traits exerted some influence on the sensitivities of lizards and snakes to ecological disturbances, although the influence of random effects was very strong. Our findings are likely to be a result of the complexity and idiosyncratic nature of natural abundance patterns among animal species, in addition to the potential confounding effect of methodological differences among studies. ImplicationsThe present study is the first major quantitative synthesis of how species traits influence population-level responses of squamate reptiles to ecological disturbances. The findings can be used to guide conservation efforts and ecological management, such as by prioritising the efforts of mitigation on species that reproduce more slowly, and those with lower body temperatures.
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Chaves Cardoso, Jéssica, Philip J. Burton i Che M. Elkin. "A Disturbance Ecology Perspective on Silvicultural Site Preparation". Forests 11, nr 12 (28.11.2020): 1278. http://dx.doi.org/10.3390/f11121278.
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Silvicultural site preparation methods are used as planned disturbances for counteracting soil and vegetation constraints, as well as facilitating successful tree regeneration and growth. Understanding the possible effects of silvicultural site preparation on the ecosystem and evaluating site preparation as an ecological disturbance can help guide the selection and application of site preparation techniques for forest management goals. This review evaluates silvicultural site preparation techniques that are commonly used in boreal mixedwood ecosystems as agents of ecological disturbance by comparing the effects of each technique on the area disturbed and the degree of biomass modification, and then ordering them along a disturbance severity gradient. With a strong emphasis on the numerical estimation of the spatial footprint of different disturbances, broadcast burning typically has the highest disturbance severity, followed in order by broadcast herbicide use, mixing, plowing, disc trenching, mounding, scalping, and inverting. The evaluation of disturbance severity of various silvicultural site preparation techniques while using the proposed framework is feasible, in which quantitative assessments of area disturbed and biomass modification could be collected and assessed in most managed forests.
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Konôpka, Bohdan, Peter Zach i Ján Kulfan. "Wind – an important ecological factor and destructive agent in forests". Forestry Journal 62, nr 2 (1.06.2016): 123–30. http://dx.doi.org/10.1515/forj-2016-0013.
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AbstractWind is both an ecological provider and disturbance facilitator influences trees and other organisms in forests. Impacts of wind on induvidual trees and forests mainly depend on the strength (or intensity) of the wind and the stability of the trees. Wind causes large-scale damage to forests and serious economical losses for the forestry sector within Europe. Therefore, knowledge of interactions between wind and trees and/or forests provides the baseline for developing adequate prevention or mitigation of the negative consequences associated with wind disturbances in forest ecosystems. Herein, we analyse the wind as an ecological and disturbance factor in forests in Europe, emphasising forests in Slovakia. Here, strong winds destroy mostly spruce dominated forests in the following regions; Orava, High and Low Tatra Mountains, Great Fatra Mountains, Pohronie, Poľana Mountains and Slovak Ore Mountains. Increasing volumes of timber damaged by windstorms have been documented since 1961, with the maximum damage recorded in 2004. Yearly volumes of damaged timber of approximately 2.5 mil. m3are predicted from 2016 to 2030. This highlights the data requirement regarding wind disturbances for integrated forest protection against dangerous winds and other disturbance agents in forest ecosystems in Slovakia and other European countries.
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Taylor, Anthony R., David A. MacLean, Peter D. Neily, Bruce Stewart, Eugene Quigley, Sean P. Basquill, Celia K. Boone, Derek Gilby i Mark Pulsifer. "A review of natural disturbances to inform implementation of ecological forestry in Nova Scotia, Canada". Environmental Reviews 28, nr 4 (grudzień 2020): 387–414. http://dx.doi.org/10.1139/er-2020-0015.
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Like many jurisdictions across North America, the province of Nova Scotia (NS) is faced with the challenge of restoring its forests to a more natural, presettlement state through implementation of ecological forestry. At the core of ecological forestry is the idea that natural forest structures and processes may be approximated by designing management practices that emulate natural disturbances. Successful natural disturbance emulation depends on fundamental knowledge of disturbance characteristics, including identification of specific disturbance agents, their spatial extent, severity, and return interval. To date, no comprehensive synthesis of existing data has been undertaken to document the natural disturbance regime of NS forests, limiting the application of natural disturbance emulation. Using over 300 years of documents and available data, we identified the main natural disturbance agents that affect NS forests and characterized their regimes. Overall, fire, wind (predominantly hurricanes), and outbreaks of spruce budworm (Choristoneura fumiferana (Clemens)) are the most important disturbance agents, causing substantial areas of low- (<30% mortality), moderate- (30%–60%), and high- (>60%) severity disturbance. While characterization of natural historic fire is challenging, due to past human ignitions and suppression, we estimated that the mean annual disturbance rate of moderate- to high-severity fire ranged between 0.17% and 0.4%·year−1 (return interval of 250–600 years), depending on ecosystem type. Hurricanes make landfall in NS, on average, every 7 years, resulting in wide-scale (>500 ha) forest damage. While hurricane track and damage severity vary widely among storms, the return interval of low- to high-severity damage is 700–1250 years (0.14%–0.08%·year−1). Conversely, the return interval of host-specific spruce budworm outbreaks is much shorter (<50 years) but more periodic, causing wide-scale, low- to high-severity damage to spruce–fir forests every 30–40 years. Further disturbance agents such as other insects (e.g., spruce beetle), diseases, ice storms, drought, and mammals can be locally important and (or) detrimental to individual tree species but contribute little to overall disturbance in NS. Climate change is expected to significantly alter the disturbance regime of NS, affecting current disturbances (e.g., increased fire) and driving the introduction of novel agents (e.g., hemlock wooly adelgid), and continued monitoring is needed to understand these changes.
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Burton, Philip J., Anke Jentsch i Lawrence R. Walker. "The Ecology of Disturbance Interactions". BioScience 70, nr 10 (16.09.2020): 854–70. http://dx.doi.org/10.1093/biosci/biaa088.
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Abstract Global change has been accompanied by recent increases in the frequency and intensity of various ecological disturbances (e.g., fires, floods, cyclones), both natural and anthropogenic in origin. Because these disturbances often interact, their cumulative and synergistic effects can result in unforeseen consequences, such as insect outbreaks, crop failure, and progressive ecosystem degradation. We consider the roles of biological legacies, thresholds, and lag effects responsible for the distinctive impacts of interacting disturbances. We propose a hierarchical classification that distinguishes the patterns and implications associated with random co-occurrences, individual links, and multiple links among disturbances that cascade in chains or networks. Disturbance-promoting interactions apparently prevail over disturbance-inhibiting ones. Complex and exogenous disturbance cascades are less predictable than simple and endogenous links because of their dependency on adjacent or synchronous events. These distinctions help define regional disturbance regimes and can have implications for natural selection, risk assessment, and options for management intervention.
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Rocha, Bernardo, Pedro Pinho, Joana Vieira, Cristina Branquinho i Paula Matos. "Testing the Poleotolerance Lichen Response Trait as an Indicator of Anthropic Disturbance in an Urban Environment". Diversity 11, nr 4 (6.04.2019): 55. http://dx.doi.org/10.3390/d11040055.
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Urban environments are densely populated areas buzzing with a wide range of anthropic activities that cause disturbances like air pollution or the heat island effect, threatening both human and environmental health. Mitigating its impacts implies understanding the integrated effects that those disturbances exert on urban environments. Lichen biodiversity is frequently used as an ecological indicator, being able to integrate its effects in a quantifiable way. The poleotolerance response trait classifies lichens according to their tolerance to human disturbance, but it was developed for Italy’s flora and has seldom been applied outside Italy or in urban context studies. The aim of this work was to assess this trait suitability as an indicator of urban anthropic disturbance and test it outside Italy. For that, we sampled lichen diversity in 41 green spaces in Lisbon. Lichens were classified into the respective poleotolerance trait functional groups and their community weighted mean related with three type of environmental variables used as surrogates of urban disturbance. We showed that disturbance-tolerant functional groups could be used as an ecological indicator of the integrated effects of environmental disturbances. Some species were clearly misclassified, so we propose reclassification for those. Natural and seminatural functional groups did not behave as expected. Nevertheless, disturbance-tolerant functional groups have the potential to be used in in other Southern European cities.
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Calder, W. John, i Bryan Shuman. "Detecting past changes in vegetation resilience in the context of a changing climate". Biology Letters 15, nr 3 (marzec 2019): 20180768. http://dx.doi.org/10.1098/rsbl.2018.0768.
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Anthropogenic climate change is continuously altering ecological responses to disturbance and must be accounted for when examining ecological resilience. One way to measure resilience in ecological datasets is by considering the amount and duration of change from a baseline created by perturbations, such as disturbances like wildfire. Recovery occurs when ecological conditions return to equilibrium, meaning that no subsequent changes can be attributed to the effects of the disturbance, but climate change often causes the recovered state to differ from the previous baseline. The palaeoecological record provides an opportunity to examine these expectations because palaeoclimates changed continuously; few periods existed when environmental conditions were stationary. Here we demonstrate a framework for examining resilience in palaeoecological records against the backdrop of a non-stationary climate by considering resilience as two components of (i) resistance (magnitude of change) and (ii) recovery (time required to return) to predicted equilibrium values. Measuring these components of resilience in palaeoecological records requires high-resolution fossil (e.g. pollen) records, local palaeoclimate reconstructions, a model to predict ecological change in response to climate change, and disturbance records measured at the same spatial scale as the ecological (e.g. vegetation history) record. Resistance following disturbance is measured as the deviation of the fossil record from the ecological state predicted by the palaeoclimate records, and recovery time is measured as the time required for the fossil record to return to predicted values. We show that some cases may involve nearly persistent equilibrium despite large climate changes, but that others can involve a shift to a new state without any complete recovery.
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Lear, Luke, Elze Hesse, Katriona Shea i Angus Buckling. "Disentangling the mechanisms underpinning disturbance-mediated invasion". Proceedings of the Royal Society B: Biological Sciences 287, nr 1919 (29.01.2020): 20192415. http://dx.doi.org/10.1098/rspb.2019.2415.
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Disturbances can play a major role in biological invasions: by destroying biomass, they alter habitat and resource abundances. Previous field studies suggest that disturbance-mediated invader success is a consequence of resource influxes, but the importance of other potential covarying causes, notably the opening up of habitats, have yet to be directly tested. Using experimental populations of the bacterium Pseudomonas fluorescens , we determined the relative importance of disturbance-mediated habitat opening and resource influxes, plus any interaction between them, for invader success of two ecologically distinct morphotypes. Resource addition increased invasibility, while habitat opening had little impact and did not interact with resource addition. Both invaders behaved similarly, despite occupying different ecological niches in the microcosms. Treatment also affected the composition of the resident population, which further affected invader success. Our results provide experimental support for the observation that resource input is a key mechanism through which disturbance increases invasibility.
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Levin, Donald A. "Ecological Speciation: The Role of Disturbance". Systematic Botany 29, nr 2 (1.04.2004): 225–33. http://dx.doi.org/10.1600/036364404774195449.
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RYKIEL, EDWARD J. "Towards a definition of ecological disturbance". Austral Ecology 10, nr 3 (wrzesień 1985): 361–65. http://dx.doi.org/10.1111/j.1442-9993.1985.tb00897.x.
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Gerritsen, Jeroen, i Bernard C. Patten. "System theory formulation of ecological disturbance". Ecological Modelling 29, nr 1-4 (wrzesień 1985): 383–97. http://dx.doi.org/10.1016/0304-3800(85)90062-6.
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Muskal, Fred. "Sociological/ecological theories of emotional disturbance". Journal of Developmental and Physical Disabilities 3, nr 3 (wrzesień 1991): 267–88. http://dx.doi.org/10.1007/bf01045978.
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Jacquet, Claire, i Florian Altermatt. "The ghost of disturbance past: long-term effects of pulse disturbances on community biomass and composition". Proceedings of the Royal Society B: Biological Sciences 287, nr 1930 (8.07.2020): 20200678. http://dx.doi.org/10.1098/rspb.2020.0678.
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Current global change is associated with an increase in disturbance frequency and intensity, with the potential to trigger population collapses and to cause permanent transitions to new ecosystem states. However, our understanding of ecosystem responses to disturbances is still incomplete. Specifically, there is a mismatch between the diversity of disturbance regimes experienced by ecosystems and the one-dimensional description of disturbances used in most studies on ecological stability. To fill this gap, we conducted a full factorial experiment on microbial communities, where we varied the frequency and intensity of disturbances affecting species mortality, resulting in 20 different disturbance regimes. We explored the direct and long-term effects of these disturbance regimes on community biomass. While most communities were able to recover biomass and composition states similar to undisturbed controls after a halt of the disturbances, we identified some disturbance thresholds that had long-lasting legacies on communities. Using a model based on logistic growth, we identified qualitatively the sets of disturbance frequency and intensity that had equivalent long-term negative impacts on experimental communities. Our results show that an increase in disturbance intensity is a bigger threat for biodiversity and biomass recovery than the occurrence of more frequent but less intense disturbances.
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Ojha, Santosh K., Kozma Naka i Luben D. Dimov. "Assessment of Disturbances across Forest Inventory Plots in the Southeastern United States for the Period 1995–2018". Forest Science 66, nr 2 (26.11.2019): 242–55. http://dx.doi.org/10.1093/forsci/fxz072.
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Abstract Disturbances of varying frequency and intensity shape the species composition, stand structure, and functions of forests. This study assessed the frequency and distribution of disturbances caused by eight agents (insects, diseases, fire, animals, weather, other vegetation, human, and unknown) in the forests of the southeastern United States from 1995 to 2018. We used data from 88,722 inventory measurements of 33,531 plots from the USDA Forest Inventory and Analysis database to assess disturbance among different forest types and to different canopy strata. Disturbances were detected in approximately 14 percent of the plots, located mostly in pine-dominated forest types. Fire was the most frequent disturbance agent (occurring 6 percent of the time), followed by weather and animal agents. The agents that caused the highest mortality rate during the period for saplings were silvicultural treatments (8.6 percent), other vegetation (5.6 percent), and fire (4.4 percent), whereas for trees they were silvicultural treatments (9.8 percent), weather (1.9 percent) and insects (1.7 percent). The forest type that appeared to have been most affected by disturbances was longleaf–slash pine of the Coastal Plain. These results are useful for understanding the spatiotemporal distribution of disturbance events in different southeastern forest types and locations and for guiding forest management activities to mitigate potential impacts.
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Little, L. R., i R. Q. Grafton. "Environmental offsets, resilience and cost-effective conservation". Royal Society Open Science 2, nr 7 (lipiec 2015): 140521. http://dx.doi.org/10.1098/rsos.140521.
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Conservation management agencies are faced with acute trade-offs when dealing with disturbance from human activities. We show how agencies can respond to permanent ecosystem disruption by managing for Pimm resilience within a conservation budget using a model calibrated to a metapopulation of a coral reef fish species at Ningaloo Reef, Western Australia. The application is of general interest because it provides a method to manage species susceptible to negative environmental disturbances by optimizing between the number and quality of migration connections in a spatially distributed metapopulation. Given ecological equivalency between the number and quality of migration connections in terms of time to recover from disturbance, our approach allows conservation managers to promote ecological function, under budgetary constraints, by offsetting permanent damage to one ecological function with investment in another.
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Wernberg, T., M. Couraudon-Réale, F. Tuya i M. Thomsen. "Disturbance intensity, disturbance extent and ocean climate modulate kelp forest understory communities". Marine Ecology Progress Series 651 (1.10.2020): 57–69. http://dx.doi.org/10.3354/meps13443.
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Disturbances often control community structure by removing large dominant species, allowing new species to colonize. Disturbances vary in intensity and extent, and their effects on resident communities can depend on local environmental conditions. We tested the effects of disturbance intensity and extent on different functional groups of understory species in kelp forests at 4 locations along an ocean climate gradient in Western Australia. We hypothesized that, compared to intact canopies, increasing disturbance intensities (50 and 100% of kelp removal) and extents (2, 4 and 8 m diameter) would promote light-dependent competitors (turf, foliose, articulated coralline and fucoid seaweeds) at the expense of less light-dependent functional groups (invertebrates and encrusting seaweeds). We also hypothesized that these effects would be most pronounced at warmer relative to cooler locations, where metabolic and ecological rates are faster. The first hypothesis was supported; light-dependent understory groups (turfs, in particular) increased, while less light-dependent groups (crusts in particular) decreased with increasing disturbance regimes. However, the second hypothesis was not supported; even though understory communities differed between locations and turf covers were highest at the warmest location, we found no significant interactions between locations and disturbance regimes. Importantly, our results revealed that even small-scale partial canopy loss can have significant effects on kelp-associated communities. The implied community-wide, density-dependent effects have implications for the management and conservation of kelp forests, because restoration of ecological functions must also consider the density of kelp forests, not simply their presence or absence.
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Yubang, LIU, LIANG Chuan, YE ming i XIANG Jie. "Ecological Analysis of Disturbance and Disturbance Intensity Estimates for Rainwater Harvesting". Polish Journal of Environmental Studies 24 (2015): 1153–58. http://dx.doi.org/10.15244/pjoes/29945.
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Drever, C. Ronnie, Garry Peterson, Christian Messier, Yves Bergeron i Mike Flannigan. "Can forest management based on natural disturbances maintain ecological resilience?" Canadian Journal of Forest Research 36, nr 9 (1.09.2006): 2285–99. http://dx.doi.org/10.1139/x06-132.
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Given the increasingly global stresses on forests, many ecologists argue that managers must maintain ecological resilience: the capacity of ecosystems to absorb disturbances without undergoing fundamental change. In this review we ask: Can the emerging paradigm of natural-disturbance-based management (NDBM) maintain ecological resilience in managed forests? Applying resilience theory requires careful articulation of the ecosystem state under consideration, the disturbances and stresses that affect the persistence of possible alternative states, and the spatial and temporal scales of management relevance. Implementing NDBM while maintaining resilience means recognizing that (i) biodiversity is important for long-term ecosystem persistence, (ii) natural disturbances play a critical role as a generator of structural and compositional heterogeneity at multiple scales, and (iii) traditional management tends to produce forests more homogeneous than those disturbed naturally and increases the likelihood of unexpected catastrophic change by constraining variation of key environmental processes. NDBM may maintain resilience if silvicultural strategies retain the structures and processes that perpetuate desired states while reducing those that enhance resilience of undesirable states. Such strategies require an understanding of harvesting impacts on slow ecosystem processes, such as seed-bank or nutrient dynamics, which in the long term can lead to ecological surprises by altering the forest's capacity to reorganize after disturbance.
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Cheng, Peng, Yiyu Qin, Siyang Zhu i Xuesong Kong. "Ecological Disturbance of Rural Settlement Expansion: Evidence from Nantong, Eastern China". Land 11, nr 10 (8.10.2022): 1741. http://dx.doi.org/10.3390/land11101741.
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Rural settlements are undergoing a reconstruction process in the context of rapid urbanization, which has a significant impact on ecological land. However, rural settlements encroaching on ecological land (RSEEL) and its associated ecological effects have been widely ignored. This paper aims to accurately and quantitatively evaluate the ecological disturbance caused by RSEEL in China’s rapid urbanization areas. An ecological disturbance index combining changes in both the scale and fragmentation was applied in Nantong, Eastern China. Three types, including jump expansion, extension diffusion, and internal filling, were identified in RSEEL. The results show that the jump expansion type accounted for the largest proportion (58.39%) at the patch level, whereas the extension diffusion was the dominant type at the village level, and the internal filling type was the least common. RSEEL unexpectedly did not make ecological land more fragmented due to the preference for small independent patches in most encroachment cases; hence, the degree of ecological disturbance caused by RSEEL was low in most areas of Nantong. When the encroachment type of RSEEL was combined with the ecological disturbance degree, it was found that the ecological disturbance caused by the jump expansion type was higher than that of the other two types, and extension diffusion and low-level disturbance was the main pattern observed in villages. The findings will contribute to our understanding of the dynamic relationship between rural settlement and ecological land and provide valuable information for rural settlement reconstruction under ecological civilization.
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Gaiser, Evelyn E., David M. Bell, Max C. N. Castorani, Daniel L. Childers, Peter M. Groffman, C. Rhett Jackson, John S. Kominoski i in. "Long-Term Ecological Research and Evolving Frameworks of Disturbance Ecology". BioScience 70, nr 2 (29.01.2020): 141–56. http://dx.doi.org/10.1093/biosci/biz162.
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Abstract Detecting and understanding disturbance is a challenge in ecology that has grown more critical with global environmental change and the emergence of research on social–ecological systems. We identify three areas of research need: developing a flexible framework that incorporates feedback loops between social and ecological systems, anticipating whether a disturbance will change vulnerability to other environmental drivers, and incorporating changes in system sensitivity to disturbance in the face of global changes in environmental drivers. In the present article, we review how discoveries from the US Long Term Ecological Research (LTER) Network have influenced theoretical paradigms in disturbance ecology, and we refine a framework for describing social–ecological disturbance that addresses these three challenges. By operationalizing this framework for seven LTER sites spanning distinct biomes, we show how disturbance can maintain or alter ecosystem state, drive spatial patterns at landscape scales, influence social–ecological interactions, and cause divergent outcomes depending on other environmental changes.
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Norderhaug, KM, K. Filbee-Dexter, C. Freitas, SR Birkely, L. Christensen, I. Mellerud, J. Thormar i in. "Ecosystem-level effects of large-scale disturbance in kelp forests". Marine Ecology Progress Series 656 (10.12.2020): 163–80. http://dx.doi.org/10.3354/meps13426.
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Understanding the effects of ecological disturbances in coastal habitats is crucial and timely as these are anticipated to increase in intensity and frequency in the future due to increasing human pressure. In this study we used directed kelp trawling as a scientific tool to quantify the impacts of broad-scale disturbance on community structure and function. We tested the ecosystem-wide effects of this disturbance in a BACI design using two 15 km2 areas. The disturbance had a substantial impact on the kelp forests in this study, removing 2986 tons of kelp and causing a 26% loss of total kelp canopy at trawled stations. This loss created a 67% reduction of epiphytes, an 89% reduction of invertebrates and altered the fish populations living within these habitats. The effect of habitat loss on fish was variable and depended on how the different species used the habitat structure. Our results show that large-scale experimental disturbances on habitat-forming species have ecological consequences that extend beyond the decline of the single species to affect multiple trophic levels of the broader ecosystem. Our findings have relevance for understanding how increasing anthropogenic disturbances, including kelp trawling and increased storm frequency caused by climate change, may alter ecosystem structure and function.
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Johnson, E. A. "Disturbance: the process and the response. An epilogue". Canadian Journal of Forest Research 15, nr 1 (1.02.1985): 292–93. http://dx.doi.org/10.1139/x85-047.
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One gap in our understanding of disturbances became evident during this symposium and in the discussions before and after: How did the disturbances work and how exactly did they affect plants? In this epilogue I consider why the traditional study of succession by describing developmental sequences has led to such a slow formulation of the coupling of disturbance processes to ecological responses. A conceptual framework is also suggested for the coupling of process and response.
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Ke, Shan, Hui Pan i Bowen Jin. "Identification of Priority Areas for Ecological Restoration Based on Human Disturbance and Ecological Security Patterns: A Case Study of Fuzhou City, China". Sustainability 15, nr 3 (3.02.2023): 2842. http://dx.doi.org/10.3390/su15032842.
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The rapid increase in urbanization has brought about a great deal of ecological problems, and thus the systematic protection of the environment is vital. Ecological security patterns are important for maintaining regional ecological stability and sustainable urban development. Human disturbance is a key factor affecting the stability and sustainable development of ecosystems. This paper constructs an ecological security pattern and evaluates the degree of human disturbance in Fuzhou City. Through a comprehensive analysis of both of these factors, the ecological priority restoration areas in Fuzhou were identified. The study shows that (1) there are 40 ecological source areas in Fuzhou, with a total area of 4556.48 km2; 83 ecological corridors, with a total distance of 179.33 km; and 30 ecological nodes. (2) The human disturbance degree score in the study area is between 0 and 0.8. The degree of human disturbance forms two larger major cores in Cangshan District, Gulou District, and Fuqing City. (3) The scores for the degree of human disturbance with ecological sources range from 0 to 0.42. The high-priority areas in the study area are distributed at the edges of ecological sources and form two high-scoring aggregation areas in Fuqing City and Jinan District. These corridors have a high degree of human disturbance with scores between 0 and 0.56. The I and II priority areas are mostly found in longer corridors in Fuqing City and Cangshan District near coastal or urban centers, and the III priority areas are mainly distributed in ecological corridors near the inland. The human disturbance degree scores of the nodes range from 0.01 to 0.27, and the nodes with higher grades were mainly distributed in the northeast, southeast, northwest and southwest of the study area.
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Sanz-Lazaro, Carlos. "A Framework to Advance the Understanding of the Ecological Effects of Extreme Climate Events". Sustainability 11, nr 21 (25.10.2019): 5954. http://dx.doi.org/10.3390/su11215954.
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Climate change is modifying disturbance regimes, affecting the severity and occurrence of extreme events. Current experiments investigating extreme events have a large diversity of experimental approaches and key aspects such as the interaction with other disturbances, the timing, and long-term effects are not usually incorporated in a standardized way. This lack of comparability among studies limits advances in this field of research. This study presents a framework that is comprised of two experimental approaches designed to test expected changes on disturbance regime due to climate change. These approaches test the effects of disturbances becoming more clustered and more extreme. They use common descriptor variables regardless of the type of disturbance and ecosystem. This framework is completed with a compilation of procedures that increase the realism of experiments in the aforementioned key aspects. The proposed framework favours comparability among studies and increases our understanding of extreme events. Examples to implement this framework are given using rocky shores as a case study. Far from being perfect, the purpose of this framework is to act as a starting point that triggers the comparability and refinement of these types of experiments needed to advance our understanding of the ecological effects of extreme events.
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PASCUAL, M., i F. GUICHARD. "Criticality and disturbance in spatial ecological systems". Trends in Ecology & Evolution 20, nr 2 (luty 2005): 88–95. http://dx.doi.org/10.1016/j.tree.2004.11.012.
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Banks, Sam C., Geoffrey J. Cary, Annabel L. Smith, Ian D. Davies, Don A. Driscoll, A. Malcolm Gill, David B. Lindenmayer i Rod Peakall. "How does ecological disturbance influence genetic diversity?" Trends in Ecology & Evolution 28, nr 11 (listopad 2013): 670–79. http://dx.doi.org/10.1016/j.tree.2013.08.005.
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Harvey, Eric, Isabelle Gounand, Emanuel A. Fronhofer i Florian Altermatt. "Disturbance reverses classic biodiversity predictions in river-like landscapes". Proceedings of the Royal Society B: Biological Sciences 285, nr 1893 (12.12.2018): 20182441. http://dx.doi.org/10.1098/rspb.2018.2441.
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Global analyses of biodiversity consistently reveal recurrent patterns of species distributions worldwide. However, unveiling the specific mechanisms behind those patterns remains logistically challenging, yet necessary for reliable biodiversity forecasts. Here, we combine theory and experiments to investigate the processes underlying spatial biodiversity patterns in dendritic, river-like landscapes, iconic examples of highly threatened ecosystems. We used geometric scaling properties, common to all rivers, to show that the distribution of biodiversity in these landscapes fundamentally depends on how ecological selection is modulated across space: while uniform ecological selection across the network leads to higher diversity in downstream confluences, this pattern can be inverted by disturbances when population turnover (i.e. local mortality) is higher upstream than downstream. Higher turnover in small headwater patches can slow down ecological selection, increasing local diversity in comparison to large downstream confluences. Our results show that disturbance-mediated slowing down of competitive exclusion can generate a specific transient signature in terms of biodiversity distribution when applied over a spatial gradient of disturbance, which is a common feature of many river landscapes.
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DELGADO, JUAN D., RODRIGO RIERA, RICARDO A. RODRÍGUEZ, PABLO GONZÁLEZ-MORENO i JOSÉ MARÍA FERNÁNDEZ-PALACIOS. "A reappraisal of the role of humans in the biotic disturbance of islands". Environmental Conservation 44, nr 4 (12.04.2017): 371–80. http://dx.doi.org/10.1017/s0376892917000236.
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SUMMARYTraditionally, islands have been used as ecological and biogeographical models because of their assumed ecological simplicity, reduced ecosystem size and isolation. The vast number of Earth's oceanic islands play a key role in maintaining global biodiversity and serve as a rich source of evolutionary novelty. Research into the factors determining diversity patterns on islands must disentangle natural phenomena from anthropogenic causes of habitat transformation, interruption and enhancement of biological fluxes and species losses and gains in these geographically and ecologically limited environments. The anthropogenic ecological forcing of communication through global transport has profound implications regarding island–continent links. Anthropogenic disturbances along continental margins and insular coasts contribute to shaping island biotas in ecological time, but also have evolutionary consequences of global resonance. Patterns of human landscape and resource use (geographical space and ecological communities and species), as well as increasing ecological connectivity of oceanic islands and mainland, are chief driving forces in island biogeography that should be reappraised. Global indirect effects of human activities (i.e. climate change) may also affect islands and interact with these processes. We review the implications of direct and indirect anthropogenic disturbances on island biotic patterns, focusing on island size, isolation and introduced exotic species, as well as the unsettled issue of oceanic island ecological vulnerability.
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Yimer, Hayal Desta, i Seyoum Mengistou. "Water Quality Parameters and Macroinvertebrates Index of Biotic Integrity of the Jimma Wetlands, Southwestern Ethiopia". Journal of Wetlands Ecology 3 (11.02.2010): 79–99. http://dx.doi.org/10.3126/jowe.v3i0.2265.
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The wetlands located at the periphery of Jimma town, southwestern Ethiopia, have critical roles in providing a range of ecological and socio-economic benefits, yet they are subject to increasing anthropogenic disturbances, notably through agriculture, settlement, intensive grazing and brick-making. This study assessed the ecological status of these wetlands, and examined the scale of the human disturbances that local communities might impose on them. Macroinvertebrate communities, water quality parameters, and human disturbance scores were assessed. Except for electrical conductivity and water temperature, no significant difference (P < 0.05) was found in physico-chemical parameters between the sampled sites. Nitrate was the only parameter that correlated with significant influence on species richness of the sampled macroinvertebrates. A total of 10 metrics were used to generate the index of biotic integrity (IBI). This IBI was then tested based on macroinvertebrate data collected. Ways of assessing and evaluating the existing ecological status of the wetlands are discussed in the context of physico-chemical parameters, IBI based on macroinvertebrates and human disturbance scales. Key Words: Catchments land use; Water quality; Macroinvertebrate; Index of Biotic Integrity; Wetland DOI: 10.3126/jowe.v3i0.2265 Journal of Wetlands Ecology, (2009) Vol. 3, pp 77-93
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TURNER, MONICA G., SCOTT L. COLLINS, ARIEL L. LUGO, JOHN J. MAGNUSON, T. SCOTT RUPP i FREDERICK J. SWANSON. "Disturbance Dynamics and Ecological Response: The Contribution of Long-Term Ecological Research". BioScience 53, nr 1 (2003): 46. http://dx.doi.org/10.1641/0006-3568(2003)053[0046:ddaert]2.0.co;2.
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Liu, Yunxuan, Miaomiao Xie, Jinying Liu, Huihui Wang i Bin Chen. "Vegetation Disturbance and Recovery Dynamics of Different Surface Mining Sites via the LandTrendr Algorithm: Case Study in Inner Mongolia, China". Land 11, nr 6 (6.06.2022): 856. http://dx.doi.org/10.3390/land11060856.
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Mining sites are areas where mining and restoration coexist and are constantly changing. The vegetation condition can reflect the process of surface mining and restoration, while quantifying the impacts of different mining patterns and surrounding environments on vegetation is the key to balancing mining activities and ecological restoration. In this study, long-term monitoring from 1986 to 2020 was implemented by the LandTrendr algorithm to reveal the ecological impacts of two concentrated and contiguous surface mining sites with different mining patterns (scattered and aggregated mining) and surrounding environments in Inner Mongolia, China. The results show that it is reasonable to use the LandTrendr algorithm for long-term monitoring of surface mining sites, and that the ecological impacts of different surface mining sites in ecologically fragile areas have the same regularity. As the duration increases, the magnitude of disturbance decreases, and the magnitude of recovery first decreases and then reaches a natural fluctuation state after 20 years of recovery. Different mining patterns and surrounding environments bring different ecological impacts. Scattered mining areas are more likely to produce natural recovery while the restored ecosystem is more stable. The performance of mining development disturbance is more obvious in places with better ecological environment, while the effect of ecological restoration is also more significant. This study can provide guidance for the rational planning of mining and restoration activities in ecologically fragile areas.
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Jørgensen, Sven Erik. "Disturbance and ecosystems: Components of response". Ecological Modelling 34, nr 1-2 (listopad 1986): 136–37. http://dx.doi.org/10.1016/0304-3800(86)90085-2.
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Chance, Donald P., Johannah R. McCollum, Garrett M. Street, Bronson K. Strickland i Marcus A. Lashley. "Native Species Abundance Buffers Non-Native Plant Invasibility following Intermediate Forest Management Disturbances". Forest Science 65, nr 3 (25.01.2019): 336–43. http://dx.doi.org/10.1093/forsci/fxy059.
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Abstract The biotic resistance hypothesis (BRH) was proposed to explain why intermediate disturbances lead to greater resistance to non-native invasions proposing communities that are more diverse provide greater resistance. However, several empirical data sets have rejected the BRH because native and non-native species richness often have a positive relation. We tested the BRH in a mature loblolly pine (Pinus taeda) forest with a gradient of disturbance intensities including canopy reduction, canopy reduction + fire, and canopy reduction + herbicide and fire. We analyzed data from the study using a combination of Pearson’s correlation and beta regressions. Using species richness, we too would reject BRH because of a positive correlation in species richness between native and non-native plants. However, native species abundance was greatest, and non-native species abundance was lowest following intermediate disturbances. Further, native and non-native species abundances were negatively correlated in a quadratic relation across disturbance intensities, suggesting that native species abundance, rather than richness, may be the mechanism of resistance to non-native invasions. We propose that native species abundance regulates resistance to non-native invasions and that intermediate disturbances provide the greatest resistance because they promote the greatest native species abundance.
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Barbosa, BC, R. Fagundes, LF Silva, JFV Tofoli, AM Santos, BYP Imai, GG Gomes, MM Hermidorff i SP Ribeiro. "Evidences that human disturbance simplify the ant fauna associated a Stachytarpheta glabra Cham. (Verbenaceae) compromising the benefits of ant-plant mutualism". Brazilian Journal of Biology 75, nr 1 (marzec 2015): 58–68. http://dx.doi.org/10.1590/1519-6984.07213.
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Interaction among species, like ants and plants through extrafloral nectaries (EFNs), are important components of ecological communities’ evolution. However, the effect of human disturbance on such specific interactions and its ecological consequences is poorly understood. This study evaluated the outcomes of mutualism between ants and the EFN-bearing plant Stachytarpheta glabra under anthropogenic disturbance. We compared the arthropod fauna composition between two groups of twenty plant individuals, one in an area disturbed by human activities and one in a preserved area. We also check the plant investment in herbivory defense and the consequential leaf damage by herbivore. Our results indicate that such disturbances cause simplification of the associated fauna and lack of proper ant mutualist. This led to four times more herbivory on plants of disturbed areas, despite the equal amount of EFN and ant visitors and low abundance of herbivores. The high pressure of herbivory may difficult the re-establishment of S. glabra, an important pioneer species in ferruginous fields, therefore it may affect resilience of this fragile ecological community.
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Daniels, Lori D. "Western redcedar population dynamics in old-growth forests: Contrasting ecological paradigms using tree rings". Forestry Chronicle 79, nr 3 (1.06.2003): 517–30. http://dx.doi.org/10.5558/tfc79517-3.
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In coastal British Columbia, late-successional forests dominated by western redcedar (Thuja plicata Donn ex D. Don) are structurally complex, with deep multi-layered canopies, large trees that are > 250 years old, and abundant coarse woody debris (CWD). These forests are presumed to be "old-growth" forests in which fine-scale gaps are the dominant disturbance regime, accounting for their structural diversity. In this study, I have used tree-ring analyses to investigate western redcedar regeneration dynamics in these old-growth forests. Western redcedar dominates canopies of many stands, but is rare in the understorey although it tolerates shade. The traditional interpretation is that western redcedar depends on catastrophic disturbance to regenerate and that it is replaced through succession by western hemlock (Tsuga heterophylla (Raf.) Sarg.) and Pacific silver fir (Abies amabilis (Dougl. ex Loud.) Dougl. ex J. Forbes), which are abundant in the understorey. Dominant trees are perceived to represent an even-aged, post-disturbance cohort and the lack of regeneration indicates a population decline in the absence of catastrophic disturbances. In this paper, I investigate four assumptions underlying this interpretation: (1) Tree size indicates age. (2) Populations establish as even-aged, post-disturbance cohorts. (3) Abundant CWD represents recent mortality. (4) Regeneration is insufficient to maintain canopy dominance. Using tree-ring evidence, I show that population dynamics of western redcedar are a combination of gap-phase establishment and a continuous mode of recruitment from the sub-canopy to the canopy. Specifically, size is a poor surrogate for tree age. Age distributions from 15 sites revealed uneven-aged populations, rather than single post-disturbance cohorts. Both logs and snags of western redcedar may persist more than 270 years; they do not represent recent mortality that is disproportionate to the number of live western redcedar in canopy. The regeneration niches of western redcedar and western hemlock overlap. For both species, gap-phase disturbances result in substrate suitable for successful seedling establishment. Preliminary results from dendroecological analysis of radial growth rates of trees in the subcanopy and canopy strata suggest that western hemlock and Pacific silver fir depend on gaps to recruit to the upper canopy, but recruitment of western redcedar may be independent of canopy gaps. I propose that differences in mode of recruitment to the canopy may explain the differences in population structures between western redcedar, western hemlock, and Pacific silver fir in the old-growth forest. These results provide an ecological precedent for use of a range of silvicultural systems, including clearcuts through single-tree harvesting and protection forests, when managing western redcedar in coastal British Columbia. Key words: Coastal British Columbia, disturbance regimes, regeneration dynamics, Thuja plicata, variable retention silviculture
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Keitt, Timothy H. "Coherent ecological dynamics induced by large-scale disturbance". Nature 454, nr 7202 (1.07.2008): 331–34. http://dx.doi.org/10.1038/nature06935.
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Karlson, R. H., i L. E. Hurd. "Disturbance, coral reef communities, and changing ecological paradigms". Coral Reefs 12, nr 3-4 (listopad 1993): 117–25. http://dx.doi.org/10.1007/bf00334469.
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Borics, Gábor, Gábor Várbíró i Judit Padisák. "Disturbance and stress: different meanings in ecological dynamics?" Hydrobiologia 711, nr 1 (1.03.2013): 1–7. http://dx.doi.org/10.1007/s10750-013-1478-9.
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Johnstone, Jill F., Craig D. Allen, Jerry F. Franklin, Lee E. Frelich, Brian J. Harvey, Philip E. Higuera, Michelle C. Mack i in. "Changing disturbance regimes, ecological memory, and forest resilience". Frontiers in Ecology and the Environment 14, nr 7 (wrzesień 2016): 369–78. http://dx.doi.org/10.1002/fee.1311.
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Stockdale, Chris, Mike Flannigan i Ellen Macdonald. "Is the END (emulation of natural disturbance) a new beginning? A critical analysis of the use of fire regimes as the basis of forest ecosystem management with examples from the Canadian western Cordillera". Environmental Reviews 24, nr 3 (wrzesień 2016): 233–43. http://dx.doi.org/10.1139/er-2016-0002.
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As our view of disturbances such as wildfire has shifted from prevention to recognizing their ecological necessity, so too forest management has evolved from timber-focused even-aged management to more holistic paradigms like ecosystem-based management. Emulation of natural disturbance (END) is a variant of ecosystem management that recognizes the importance of disturbance for maintaining ecological integrity. For END to be a successful model for forest management we need to describe disturbance regimes and implement management actions that emulate them, in turn achieving our objectives for forest structure and function. We review the different components of fire regimes (cause, frequency, extent, timing, and magnitude), we describe low-, mixed-, and high-severity fire regimes, and we discuss key issues related to describing these regimes. When characterizing fire regimes, different methods and spatial and temporal extents result in wide variation of estimates for different fire regime components. Comparing studies is difficult as few measure the same components; some methods are based on the assumption of a high-severity fire regime and are not suited to detecting mixed- or low-severity regimes, which are critical to END management, as this would affect retention in harvested areas. We outline some difficulties with using fire regimes as coarse filters for forest management, including (i) not fully understanding the interactions between fire and other disturbance agents, (ii) assuming that fire is strictly an exogenous disturbance agent that exerts top-down control of forest structure while ignoring numerous endogenous and bottom-up feedbacks on fire effects, and (iii) assuming by only replicating natural disturbance patterns we preserve ecological processes and vital ecosystem components. Even with a good understanding of a fire regime, we would still be challenged with choosing the temporal and spatial scope for the disturbance regime we are trying to emulate. We cannot yet define forest conditions that will arise from variations in disturbance regime; this then limits our ability to implement management actions that will achieve those conditions. We end by highlighting some important knowledge gaps about fire regimes and how the END model could be strengthened to achieve a more sustainable form of forest management.
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DeLong, Craig, i Del Meidinger. "Ecological variability of high elevation forests in central British Columbia". Forestry Chronicle 79, nr 2 (1.04.2003): 259–62. http://dx.doi.org/10.5558/tfc79259-2.
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High-elevation, late-successional forests over much of British Columbia are dominated by Engelmann spruce (Picea engelmannii Parry ex. Engelm.) and subalpine fir (Abies lasiocarpa (Hook.) Nutt.). Throughout the range of these forests, however, there is a wide variation in natural disturbance and successional dynamics as influenced by diverse climate and topography. We divided these high elevation forests into four groups arranged along a regional climatic gradient that affects forest composition, structure and disturbance regime. For each, we describe the climate, topography, major vegetation, and natural disturbance dynamics. We suggest that management practices reflect the ecological variability demonstrated for these high elevation forests. Key words: high elevation forests, ecological variability, natural disturbance dynamics, vegetation, Engelmann spruce, subalpine fir, British Columbia, climate, topography
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Biswas, Shekhar R., Jingyin Xiang i Hui Li. "Disturbance Effects on Spatial Autocorrelation in Biodiversity: An Overview and a Call for Study". Diversity 13, nr 4 (12.04.2021): 167. http://dx.doi.org/10.3390/d13040167.
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The spatially autocorrelated patterns of biodiversity can be an important determinant of ecological processes, functions and delivery of services across spatial scales. Therefore, understanding disturbance effects on spatial autocorrelation in biodiversity is crucial for conservation and restoration planning but remains unclear. In a survey of disturbance versus spatial patterns of biodiversity literature from forests, grasslands and savannah ecosystems, we found that habitat disturbances generally reduce the spatial autocorrelation in species diversity on average by 15.5% and reduce its range (the distance up to which autocorrelation prevails) by 21.4%, in part, due to disturbance-driven changes in environmental conditions, dispersal, species interactions, or a combination of these processes. The observed effect of disturbance, however, varied markedly among the scale of disturbance (patch-scale versus habitat-scale). Surprisingly, few studies have examined disturbance effects on the spatial patterns of functional diversity, and the overall effect was non-significant. Despite major knowledge gaps in certain areas, our analysis offers a much-needed initial insights into the disturbance-driven changes in the spatial patterns of biodiversity, thereby setting the ground for informed discussion on conservation and promotion of spatial heterogeneity in managing natural systems under a changing world.