The role of plant disease in the development of controlled ecological life support systems

NASA Technical Reports Server (NTRS)

Nelson, B.

1986-01-01

Plant diseases could be important factors affecting growth of higher plants in Closed Ecological Life Support Systems (CELSS). Disease control, therefore, will be needed to maintain healthy plants. The most important controls should be aimed at preventing the introduction, reproduction and spread of pathogens and preventing plant infection. An integrared ease control program will maximize that approach. In the design and operation of CELSS, plant disease should be considered an important aspect of plant growth. The effects of plant diseases are reviewed and several disease control measures are discussed.

INVASIVE SPECIES: PREDICTING GEOGRAPHIC DISTRIBUTIONS USING ECOLOGICAL NICHE MODELING

EPA Science Inventory

Present approaches to species invasions are reactive in nature. This scenario results in management that perpetually lags behind the most recent invasion and makes control much more difficult. In contrast, spatially explicit ecological niche modeling provides an effective solut...

Using ecological models to investigate stressor effects throughout the life cycle of mummichogs

EPA Science Inventory

Ecological models of mummichogs (Fundulus heteroclitus) provide valuable tools to link controlled laboratory experiments to field observations. Mummichogs are useful study organisms due to their amenability to laboratory conditions, the availability of well-developed molecular to...

Non-target effects of an introduced biological control agent on deer mouse ecology

Treesearch

Dean E. Pearson; Kevin S. McKelvey; Leonard F. Ruggiero

2000-01-01

Release of exotic insects as biological control agents is a common approach to controlling exotic plants. Though controversy has ensued regarding the deleterious direct effects of biological control agents to non-target species, few have examined the indirect effects of a "well-behaved" biological control agent on native fauna. We studied a grassland in west-...

The Use of Footstep Sounds as Rhythmic Auditory Stimulation for Gait Rehabilitation in Parkinson's Disease: A Randomized Controlled Trial.

PubMed

Murgia, Mauro; Pili, Roberta; Corona, Federica; Sors, Fabrizio; Agostini, Tiziano A; Bernardis, Paolo; Casula, Carlo; Cossu, Giovanni; Guicciardi, Marco; Pau, Massimiliano

2018-01-01

The use of rhythmic auditory stimulation (RAS) has been proven useful in the management of gait disturbances associated with Parkinson's disease (PD). Typically, the RAS consists of metronome or music-based sounds (artificial RAS), while ecological footstep sounds (ecological RAS) have never been used for rehabilitation programs. The aim of this study was to compare the effects of a rehabilitation program integrated either with ecological or with artificial RAS. An observer-blind, randomized controlled trial was conducted to investigate the effects of 5 weeks of supervised rehabilitation integrated with RAS. Thirty-eight individuals affected by PD were randomly assigned to one of the two conditions (ecological vs. artificial RAS); thirty-two of them (age 68.2 ± 10.5, Hoehn and Yahr 1.5-3) concluded all phases of the study. Spatio-temporal parameters of gait and clinical variables were assessed before the rehabilitation period, at its end, and after a 3-month follow-up. Thirty-two participants were analyzed. The results revealed that both groups improved in the majority of biomechanical and clinical measures, independently of the type of sound. Moreover, exploratory analyses for separate groups were conducted, revealing improvements on spatio-temporal parameters only in the ecological RAS group. Overall, our results suggest that ecological RAS is equally effective compared to artificial RAS. Future studies should further investigate the role of ecological RAS, on the basis of information revealed by our exploratory analyses. Theoretical, methodological, and practical issues concerning the implementation of ecological sounds in the rehabilitation of PD patients are discussed. www.ClinicalTrials.gov, identifier NCT03228888.

Measuring Ecological Effects of Prescribed Fire Using Birds as Indicators of Forest Conditions

Treesearch

Nathaniel E. Seavy; John D. Alexander

2006-01-01

To evaluate the ecological effects of prescribed fire, bird and vegetation surveys were conducted in four study areas of the Klamath National Forest where prescribed fires are being used for management. Bird and vegetation data were collected at sites treated with prescribed fire and nearby untreated control sites. Data were collected at stations from 2000 (pre-...

Ecology and distribution of Bulinus truncatus in the Middle East

PubMed Central

Watson, J. M.

1958-01-01

The author gives a comprehensive account of the present status of knowledge regarding the ecology and distribution of Bulinus truncatus, the intermediate host of Schistosoma haematobium in the Middle East and North Africa. He discusses in detail the types of habitat favoured by this snail, its life-cycle and seasonal variations in its populations, the effect of ecological factors on its distribution and occurrence, and the relationship between its control and its bionomics, stressing the many aspects of these subjects that require further investigation and suggesting lines for future research. In addition, the author outlines briefly the effect of some human activities (for example, extension of irrigation and agriculture), in their relationship to the snail host, on the incidence of bilharziasis haematobia in the Middle East and Africa. He concludes the paper with a summary of the three basic needs in respect of bilharziasis control: ecological research; prevention of pollution of waters with human excrement; and avoidance of human contact with infective water. PMID:13573115

Meta-analysis of thirty-two case-control and two ecological radon studies of lung cancer.

PubMed

Dobrzynski, Ludwik; Fornalski, Krzysztof W; Reszczynska, Joanna

2018-03-01

A re-analysis has been carried out of thirty-two case-control and two ecological studies concerning the influence of radon, a radioactive gas, on the risk of lung cancer. Three mathematically simplest dose-response relationships (models) were tested: constant (zero health effect), linear, and parabolic (linear-quadratic). Health effect end-points reported in the analysed studies are odds ratios or relative risk ratios, related either to morbidity or mortality. In our preliminary analysis, we show that the results of dose-response fitting are qualitatively (within uncertainties, given as error bars) the same, whichever of these health effect end-points are applied. Therefore, we deemed it reasonable to aggregate all response data into the so-called Relative Health Factor and jointly analysed such mixed data, to obtain better statistical power. In the second part of our analysis, robust Bayesian and classical methods of analysis were applied to this combined dataset. In this part of our analysis, we selected different subranges of radon concentrations. In view of substantial differences between the methodology used by the authors of case-control and ecological studies, the mathematical relationships (models) were applied mainly to the thirty-two case-control studies. The degree to which the two ecological studies, analysed separately, affect the overall results when combined with the thirty-two case-control studies, has also been evaluated. In all, as a result of our meta-analysis of the combined cohort, we conclude that the analysed data concerning radon concentrations below ~1000 Bq/m3 (~20 mSv/year of effective dose to the whole body) do not support the thesis that radon may be a cause of any statistically significant increase in lung cancer incidence.

[Simulation of urban ecological security pattern based on cellular automata: a case of Dongguan City, Guangdong Province of South China].

PubMed

Yang, Qing-Sheng; Qiao, Ji-Gang; Ai, Bin

2013-09-01

Taking the Dongguan City with rapid urbanization as a case, and selecting landscape ecological security level as evaluation criterion, the urbanization cellular number of 1 km x 1 km ecological security cells was obtained, and imbedded into the transition rules of cellular automata (CA) as the restraint term to control urban development, establish ecological security urban CA, and simulate ecological security urban development pattern. The results showed the integrated landscape ecological security index of the City decreased from 0.497 in 1998 to 0.395 in 2005, indicating that the ecological security at landscape scale was decreased. The CA-simulated integrated ecological security index of the City in 2005 was increased from the measured 0.395 to 0.479, showing that the simulated urban landscape ecological pressure from human became lesser, ecological security became better, and integrated landscape ecological security became higher. CA could be used as an effective tool in researching urban ecological security.

Six-year changes in mortality and crown condition of old-growth ponderosa pines in ecological restoration treatments at the G. A. Pearson Natural Area

Treesearch

Thomas E. Kolb; Peter Z. Fule; Michael R. Wagner; W. Wallace Covington

2001-01-01

Ecological restoration treatments using thinning and prescribed burning have been proposed to reverse the decline of old-growth ponderosa pines in the Southwest. However, long-term data on the effectiveness of such treatments are lacking. In 1993-1994, two ecological restoration treatments and a control were established at the G. A. Pearson Natural Area (GPNA) near...

Space, time and thrips: biogeographic issues in the evolutionary ecology of Thysanoptera

Treesearch

John R. Grehan

1991-01-01

Most participants of this symposium will be concerned with understanding thrips ecology primarily in order to develop practical and effective control strategies. Questions dealing with historical aspects (evolution) may seem of only isolated "theoretical" interest with little significance for everyday pragmatic concerns. Evolutionary theory is widely...

Ecological control line: A decade of exploration and an innovative path of ecological land management for megacities in China.

PubMed

Hong, Wuyang; Yang, Chengyun; Chen, Liuxin; Zhang, Fangfang; Shen, Shaoqing; Guo, Renzhong

2017-04-15

Ecological control line is a system innovation in the field of ecological environment protection in China and it has become as an important strategy of national ecological protection. Ten years have passed since the first ecological control line in Shenzhen was delimited in 2005. This study examines the connotations of ecological control line and the current study status in China and abroad, and then takes a brief description about the delimitation background and existing problems of the ecological control line in Shenzhen. The problem-solving strategy is gradually transforming from extensive management to refined management. This study proposes a differential ecological space management model that merges the space system, management system, and support system. The implementation paths include the following five aspects: delimiting ecological bottom lines to protect core ecological resources; formulating access systems for new construction projects to strictly control new construction; implementing construction land inventory reclamation assisted by market means; regulating boundary adjusting procedures and processes; and constructing ecological equity products by using multiple means to implement rights relief. Finally, this study illustrates the progress of the implementation and discusses the rigorousness and flexibility problems of ecological control line and calls for the promotion of the legislation. The management model and implementation paths proposed in this study have referential significance for developing countries and megacities to achieve ecological protection and sustainable development. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ecological impacts of winter water level drawdowns on lake littoral zones: A review

USGS Publications Warehouse

Roy, Allison

2017-01-01

Freshwater littoral zones harbor diverse ecological communities and serve numerous ecosystem functions that are controlled, in part, by natural water level fluctuations. However, human alteration of lake hydrologic regimes beyond natural fluctuations threaten littoral zone ecological integrity. One type of hydrologic alteration in lakes is winter water level drawdowns, which are frequently employed for hydropower, flood control, and macrophyte control, among other purposes. Here, we synthesize the abiotic and biotic responses to annual and novel winter water level drawdowns in littoral zones of lakes and reservoirs. The dewatering, freezing, and increased erosion of exposed lakebeds drive changes in the littoral zone. Shoreline-specific physicochemical conditions such as littoral slope and shoreline exposure further induce modifications. Loss of fine sediment decreases nutrient availability over time, but desiccation may promote a temporary nutrient pulse upon re-inundation. Annual winter drawdowns can decrease taxonomic richness of macrophytes and benthic invertebrates and shift assemblage composition to favor taxa with r-selected life history strategies and with functional traits resistant to direct and indirect drawdown effects. Fish assemblages, though less directly affected by winter drawdowns (except where there is critically low dissolved oxygen), experience negative effects via indirect pathways like decreased food resources and spawning habitat. We identify eight general research gaps to guide future research that could improve our understanding about the complex effects of winter drawdowns on littoral zone ecology.

[Eutrophication control in local area by physic-ecological engineering].

PubMed

Li, Qiu-Hua; Xia, Pin-Hua; Wu, Hong; Lin, Tao; Zhang, You-Chun; Li, Cun-Xiong; Chen, Li-Li; Yang, Fan

2012-07-01

An integrated physical and ecological engineering experiment for ecological remediation was performed at the Maixi River bay in Baihua Reservoir Guizhou Province, China. The results show that eutrophic parameters, such as total nitrogen, total phosphorus, chlorophyll a and chemical oxygen demand from the experimental site (enclosed water) were significantly lower than those of the reference site. The largest differences between the sites were 0.61 mg x L(-1), 0.041 mg x L(-1), 23.06 microg x L(-1), 8.4 mg x L(-1) respectively; experimental site transparency was > 1.50 m which was significantly higher than that of the reference site. The eutrophic index of the experimental site was oligo-trophic and mid-trophic, while the control site was mid-trophic state and eutrophic state. Phytoplankton abundance was 2 125.5 x 10(4) cells x L(-1) in June, 2011 at the control site,but phytoplankton abundance was lower at the experimental site with 33 x 10(4) cells x L(-1). Cyanobacteria dominated phytoplankton biomass at both sites, however the experimental site consisted of a higher proportion of diatoms and dinoflagellates. After more than one year of operation, the ecological engineering technology effectively controlled the occurrence of algae blooms, changed phytoplankton community structure, and controlled the negative impacts of eutrophication. Integrating physical and ecological engineering technology could improve water quality for reservoirs on the Guizhou plateau.

The role of empowerment in youth development: a study of sociopolitical control as mediator of ecological systems' influence on developmental outcomes.

PubMed

Christens, Brian D; Peterson, N Andrew

2012-05-01

Empowerment has become an influential concept and theoretical framework for social policy and practice. Still, relatively little is known about the roles that empowerment plays in the ecology of human development, particularly among young people. This article reports results of a study of psychological empowerment among young people, using data from 629 high school students (65.8% female; 96.5% non-white). Using a path analysis, we examined the role of perceived sociopolitical control--an indicator of the intrapersonal component of psychological empowerment--as a mediator between ecological support systems and developmental outcomes. Findings confirmed that social support in family, peer, and school settings, and family cohesion positively predict self-esteem and perceived school importance, which, in turn, have protective effects on psychological symptoms, violent behaviors and substance use. Sociopolitical control was found to mediate the relationships between ecological supports and risk factors and developmental outcomes, leading to the conclusion that perceived efficacy in the sociopolitical domain, and youth empowerment, more generally, should be considered as core elements of the ecology of human development. Policy and practice aimed at promoting positive developmental outcomes and preventing risk behaviors should take their relationship to sociopolitical control into account.

Current vector control challenges in the fight against malaria.

PubMed

Benelli, Giovanni; Beier, John C

2017-10-01

The effective and eco-friendly control of Anopheles vectors plays a key role in any malaria management program. Integrated Vector Management (IVM) suggests making use of the full range of vector control tools available. The strategies for IVM require novel technologies to control outdoor transmission of malaria. Despite the wide number of promising control tools tested against mosquitoes, current strategies for malaria vector control used in most African countries are not sufficient to achieve successful malaria control. The majority of National Malaria Control Programs in Africa still rely on indoor residual spraying (IRS) and long-lasting insecticidal nets (LLINs). These methods reduce malaria incidence but generally have little impact on malaria prevalence. In addition to outdoor transmission, growing levels of insecticide resistance in targeted vectors threaten the efficacy of LLINs and IRS. Larvicidal treatments can be useful, but are not recommended for rural areas. The research needed to improve the quality and delivery of mosquito vector control should focus on (i) optimization of processes and methods for vector control delivery; (ii) monitoring of vector populations and biting activity with reliable techniques; (iii) the development of effective and eco-friendly tools to reduce the burden or locally eliminate malaria and other mosquito-borne diseases; (iv) the careful evaluation of field suitability and efficacy of new mosquito control tools to prove their epidemiological impact; (v) the continuous monitoring of environmental changes which potentially affect malaria vector populations; (vi) the cooperation among different disciplines, with main emphasis on parasitology, tropical medicine, ecology, entomology, and ecotoxicology. A better understanding of behavioral ecology of malaria vectors is required. Key ecological obstacles that limit the effectiveness of vector control include the variation in mosquito behavior, development of insecticide resistance, presence of behavioral avoidance, high vector biodiversity, competitive and food web interactions, lack of insights on mosquito dispersal and mating behavior, and the impact of environmental changes on mosquito ecological traits. Overall, the trans-disciplinary cooperation among parasitologists and entomologists is crucial to ensure proper evaluation of the epidemiological impact triggered by novel mosquito vector control strategies. Copyright © 2017 Elsevier B.V. All rights reserved.

Development of a complex experimental system for controlled ecological life support technique

NASA Astrophysics Data System (ADS)

Guo, S.; Tang, Y.; Zhu, J.; Wang, X.; Feng, H.; Ai, W.; Qin, L.; Deng, Y.

A complex experimental system for controlled ecological life support technique can be used as a test platform for plant-man integrated experiments and material close-loop experiments of the controlled ecological life support system CELSS Based on lots of plan investigation plan design and drawing design the system was built through the steps of processing installation and joined debugging The system contains a volume of about 40 0m 3 its interior atmospheric parameters such as temperature relative humidity oxygen concentration carbon dioxide concentration total pressure lighting intensity photoperiod water content in the growing-matrix and ethylene concentration are all monitored and controlled automatically and effectively Its growing system consists of two rows of racks along its left-and-right sides separately and each of which holds two up-and-down layers eight growing beds hold a total area of about 8 4m 2 and their vertical distance can be adjusted automatically and independently lighting sources consist of both red and blue light-emitting diodes Successful development of the test platform will necessarily create an essential condition for next large-scale integrated study of controlled ecological life support technique

Release of genetically engineered insects: a framework to identify potential ecological effects

PubMed Central

David, Aaron S; Kaser, Joe M; Morey, Amy C; Roth, Alexander M; Andow, David A

2013-01-01

Genetically engineered (GE) insects have the potential to radically change pest management worldwide. With recent approvals of GE insect releases, there is a need for a synthesized framework to evaluate their potential ecological and evolutionary effects. The effects may occur in two phases: a transitory phase when the focal population changes in density, and a steady state phase when it reaches a new, constant density. We review potential effects of a rapid change in insect density related to population outbreaks, biological control, invasive species, and other GE organisms to identify a comprehensive list of potential ecological and evolutionary effects of GE insect releases. We apply this framework to the Anopheles gambiae mosquito – a malaria vector being engineered to suppress the wild mosquito population – to identify effects that may occur during the transitory and steady state phases after release. Our methodology reveals many potential effects in each phase, perhaps most notably those dealing with immunity in the transitory phase, and with pathogen and vector evolution in the steady state phase. Importantly, this framework identifies knowledge gaps in mosquito ecology. Identifying effects in the transitory and steady state phases allows more rigorous identification of the potential ecological effects of GE insect release. PMID:24198955

75 FR 52967 - Final Environmental Impact Statement and South Florida and Caribbean Parks Exotic Plant...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-30

... National Historic Park and Ecological Preserve, and Virgin Islands National Park. The FEIS identifies and... resources and values from adverse effects resulting from exotic plant presence and control activities. DATES... Ecological Preserve, and Virgin Islands National Park, 1300 Cruz Bay Creek, St. John, Virgin Islands 00830...

Simulation and experimental studies of operators` decision styles and crew composition while using an ecological and traditional user interface for the control room of a nuclear power plant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meshkati, N.; Buller, B.J.; Azadeh, M.A.

1995-04-01

The goal of this research is threefold: (1) use of the Skill-, Rule-, and Knowledge-based levels of cognitive control -- the SRK framework -- to develop an integrated information processing conceptual framework (for integration of workstation, job, and team design); (2) to evaluate the user interface component of this framework -- the Ecological display; and (3) to analyze the effect of operators` individual information processing behavior and decision styles on handling plant disturbances plus their performance on, and preference for, Traditional and Ecological user interfaces. A series of studies were conducted. In Part I, a computer simulation model and amore » mathematical model were developed. In Part II, an experiment was designed and conducted at the EBR-II plant of the Argonne National Laboratory-West in Idaho Falls, Idaho. It is concluded that: the integrated SRK-based information processing model for control room operations is superior to the conventional rule-based model; operators` individual decision styles and the combination of their styles play a significant role in effective handling of nuclear power plant disturbances; use of the Ecological interface results in significantly more accurate event diagnosis and recall of various plant parameters, faster response to plant transients, and higher ratings of subject preference; and operators` decision styles affect on both their performance and preference for the Ecological interface.« less

[System construction of early warning for ecological security at cultural and natural heritage mixed sites and its application: a case study of Wuyishan Scenery District].

PubMed

You, Wei-Bin; He, Dong-Jin; Qin, De-Hua; Ji, Zhi-Rong; Wu, Li-Yun; Yu, Jian-An; Chen, Bing-Rong; Tan, Yong

2014-05-01

This paper proposed a new concept of ecological security for protection by a comprehensive analysis of the contents and standards of world heritage sites. A frame concept model named "Pressure-State-Control" for early warning of ecological security at world heritage mixed sites was constructed and evaluation indicators of this frame were also selected. Wuyishan Scenery District was chosen for a case study, which has been severely disturbed by natural and artificial factors. Based on the frame model of "Pressure-State-Control" and by employing extension analysis, the matter-element model was established to assess the ecological security status of this cultural and natural world heritage mixed site. The results showed that the accuracy of ecological security early warning reached 84%. Early warning rank was I level (no alert status) in 1997 and 2009, but that in 2009 had a higher possibility to convert into II level. Likewise, the early-warning indices of sensitive ranks were different between 1997 and 2009. Population density, population growth rate, area index for tea garden, cultivated land owned per capita, level of drought, and investment for ecological and environmental construction were the main limiting factors to hinder the development of ecological security from 2009 to future. In general, the status of Wuyishan Scenery District ecological security was relatively good and considered as no alert level, while risk conditions also existed in terms of a few early-warning indicators. We still need to pay more attention to serious alert indicators and adopt effective prevention and control measures to maintain a good ecological security status of this heritage site.

Ecological feedbacks can reduce population-level efficacy of wildlife fertility control

USGS Publications Warehouse

Ransom, Jason I.; Powers, Jenny G.; Hobbs, N. Thompson; Baker, Dan L.

2014-01-01

1. Anthropogenic stress on natural systems, particularly the fragmentation of landscapes and the extirpation of predators from food webs, has intensified the need to regulate abundance of wildlife populations with management. Controlling population growth using fertility control has been considered for almost four decades, but nearly all research has focused on understanding effects of fertility control agents on individual animals. Questions about the efficacy of fertility control as a way to control populations remain largely unanswered. 2. Collateral consequences of contraception can produce unexpected changes in birth rates, survival, immigration and emigration that may reduce the effectiveness of regulating animal abundance. The magnitude and frequency of such effects vary with species-specific social and reproductive systems, as well as connectivity of populations. Developing models that incorporate static demographic parameters from populations not controlled by contraception may bias predictions of fertility control efficacy. 3. Many population-level studies demonstrate that changes in survival and immigration induced by fertility control can compensate for the reduction in births caused by contraception. The most successful cases of regulating populations using fertility control come from applications of contraceptives to small, closed populations of gregarious and easily accessed species. 4. Fertility control can result in artificial selection pressures on the population and may lead to long-term unintentional genetic consequences. The magnitude of such selection is dependent on individual heritability and behavioural traits, as well as environmental variation. 5. Synthesis and applications. Understanding species' life-history strategies, biology, behavioural ecology and ecological context is critical to developing realistic expectations of regulating populations using fertility control. Before time, effort and funding are invested in wildlife contraception, managers may need to consider the possibility that many species and populations can compensate for reduction in fecundity, and this could minimize any reduction in population growth rate.

Ecological feedbacks can reduce population-level efficacy of wildlife fertility control

PubMed Central

Ransom, Jason I; Powers, Jenny G; Thompson Hobbs, N; Baker, Dan L

2014-01-01

Anthropogenic stress on natural systems, particularly the fragmentation of landscapes and the extirpation of predators from food webs, has intensified the need to regulate abundance of wildlife populations with management. Controlling population growth using fertility control has been considered for almost four decades, but nearly all research has focused on understanding effects of fertility control agents on individual animals. Questions about the efficacy of fertility control as a way to control populations remain largely unanswered. Collateral consequences of contraception can produce unexpected changes in birth rates, survival, immigration and emigration that may reduce the effectiveness of regulating animal abundance. The magnitude and frequency of such effects vary with species-specific social and reproductive systems, as well as connectivity of populations. Developing models that incorporate static demographic parameters from populations not controlled by contraception may bias predictions of fertility control efficacy. Many population-level studies demonstrate that changes in survival and immigration induced by fertility control can compensate for the reduction in births caused by contraception. The most successful cases of regulating populations using fertility control come from applications of contraceptives to small, closed populations of gregarious and easily accessed species. Fertility control can result in artificial selection pressures on the population and may lead to long-term unintentional genetic consequences. The magnitude of such selection is dependent on individual heritability and behavioural traits, as well as environmental variation. Synthesis and applications. Understanding species' life-history strategies, biology, behavioural ecology and ecological context is critical to developing realistic expectations of regulating populations using fertility control. Before time, effort and funding are invested in wildlife contraception, managers may need to consider the possibility that many species and populations can compensate for reduction in fecundity, and this could minimize any reduction in population growth rate. PMID:25558083

Functional Group, Biomass, and Climate Change Effects on Ecological Drought in Semiarid Grasslands

NASA Astrophysics Data System (ADS)

Wilson, S. D.; Schlaepfer, D. R.; Bradford, J. B.; Lauenroth, W. K.; Duniway, M. C.; Hall, S. A.; Jamiyansharav, K.; Jia, G.; Lkhagva, A.; Munson, S. M.; Pyke, D. A.; Tietjen, B.

2018-03-01

Water relations in plant communities are influenced both by contrasting functional groups (grasses and shrubs) and by climate change via complex effects on interception, uptake, and transpiration. We modeled the effects of functional group replacement and biomass increase, both of which can be outcomes of invasion and vegetation management, and climate change on ecological drought (soil water potential below which photosynthesis stops) in 340 semiarid grassland sites over 30 year periods. Relative to control vegetation (climate and site-determined mixes of functional groups), the frequency and duration of drought were increased by shrubs and decreased by annual grasses. The rankings of shrubs, control vegetation, and annual grasses in terms of drought effects were generally consistent in current and future climates, suggesting that current differences among functional groups on drought effects predict future differences. Climate change accompanied by experimentally increased biomass (i.e., the effects of invasions that increase community biomass or management that increases productivity through fertilization or respite from grazing) increased drought frequency and duration and advanced drought onset. Our results suggest that the replacement of perennial temperate semiarid grasslands by shrubs, or increased biomass, can increase ecological drought in both current and future climates.

Functional group, biomass, and climate change effects on ecological drought in semiarid grasslands

USGS Publications Warehouse

Wilson, Scott D.; Schlaepfer, Daniel R.; Bradford, John B.; Lauenroth, William K.; Duniway, Michael C.; Hall, Sonia A.; Jamiyansharav, Khishigbayar; Jia, Gensuo; Lkhagva, Ariuntsetseg; Munson, Seth M.; Pyke, David A.; Tietjen, Britta

2018-01-01

Water relations in plant communities are influenced both by contrasting functional groups (grasses, shrubs) and by climate change via complex effects on interception, uptake and transpiration. We modelled the effects of functional group replacement and biomass increase, both of which can be outcomes of invasion and vegetation management, and climate change on ecological drought (soil water potential below which photosynthesis stops) in 340 semiarid grassland sites over 30‐year periods. Relative to control vegetation (climate and site‐determined mixes of functional groups), the frequency and duration of drought were increased by shrubs and decreased by annual grasses. The rankings of shrubs, control vegetation, and annual grasses in terms of drought effects were generally consistent in current and future climates, suggesting that current differences among functional groups on drought effects predict future differences. Climate change accompanied by experimentally‐increased biomass (i.e. the effects of invasions that increase community biomass, or management that increases productivity through fertilization or respite from grazing) increased drought frequency and duration, and advanced drought onset. Our results suggest that the replacement of perennial temperate semiarid grasslands by shrubs, or increased biomass, can increase ecological drought both in current and future climates.

Indirect ecological effects in invaded landscapes: Spillover and spillback from biological control agents to native analogues

USDA-ARS?s Scientific Manuscript database

Biological control remains an effective option for managing large-scale weed problems in natural areas. The predation or parasitism of biological control agents by other species present in the introduced range (biotic resistance) is well studied and is often cited as the cause for a lack of establis...

A modelling methodology to assess the effect of insect pest control on agro-ecosystems.

PubMed

Wan, Nian-Feng; Ji, Xiang-Yun; Jiang, Jie-Xian; Li, Bo

2015-04-23

The extensive use of chemical pesticides for pest management in agricultural systems can entail risks to the complex ecosystems consisting of economic, ecological and social subsystems. To analyze the negative and positive effects of external or internal disturbances on complex ecosystems, we proposed an ecological two-sidedness approach which has been applied to the design of pest-controlling strategies for pesticide pollution management. However, catastrophe theory has not been initially applied to this approach. Thus, we used an approach of integrating ecological two-sidedness with a multi-criterion evaluation method of catastrophe theory to analyze the complexity of agro-ecosystems disturbed by the insecticides and screen out the best insect pest-controlling strategy in cabbage production. The results showed that the order of the values of evaluation index (RCC/CP) for three strategies in cabbage production was "applying frequency vibration lamps and environment-friendly insecticides 8 times" (0.80) < "applying trap devices and environment-friendly insecticides 9 times" (0.83) < "applying common insecticides 14 times" (1.08). The treatment "applying frequency vibration lamps and environment-friendly insecticides 8 times" was considered as the best insect pest-controlling strategy in cabbage production in Shanghai, China.

A modelling methodology to assess the effect of insect pest control on agro-ecosystems

PubMed Central

Wan, Nian-Feng; Ji, Xiang-Yun; Jiang, Jie-Xian; Li, Bo

2015-01-01

The extensive use of chemical pesticides for pest management in agricultural systems can entail risks to the complex ecosystems consisting of economic, ecological and social subsystems. To analyze the negative and positive effects of external or internal disturbances on complex ecosystems, we proposed an ecological two-sidedness approach which has been applied to the design of pest-controlling strategies for pesticide pollution management. However, catastrophe theory has not been initially applied to this approach. Thus, we used an approach of integrating ecological two-sidedness with a multi-criterion evaluation method of catastrophe theory to analyze the complexity of agro-ecosystems disturbed by the insecticides and screen out the best insect pest-controlling strategy in cabbage production. The results showed that the order of the values of evaluation index (RCC/CP) for three strategies in cabbage production was “applying frequency vibration lamps and environment-friendly insecticides 8 times” (0.80) < “applying trap devices and environment-friendly insecticides 9 times” (0.83) < “applying common insecticides 14 times” (1.08). The treatment “applying frequency vibration lamps and environment-friendly insecticides 8 times” was considered as the best insect pest-controlling strategy in cabbage production in Shanghai, China. PMID:25906199

Heavily Oiled Salt Marsh following the Deepwater Horizon Oil Spill, Ecological Comparisons of Shoreline Cleanup Treatments and Recovery

PubMed Central

Zengel, Scott; Bernik, Brittany M.; Rutherford, Nicolle; Nixon, Zachary; Michel, Jacqueline

2015-01-01

The Deepwater Horizon oil spill affected hundreds of kilometers of coastal wetland shorelines, including salt marshes with persistent heavy oiling that required intensive shoreline “cleanup” treatment. Oiled marsh treatment involves a delicate balance among: removing oil, speeding the degradation of remaining oil, protecting wildlife, fostering habitat recovery, and not causing further ecological damage with treatment. To examine the effectiveness and ecological effects of treatment during the emergency response, oiling characteristics and ecological parameters were compared over two years among heavily oiled test plots subject to: manual treatment, mechanical treatment, natural recovery (no treatment, oiled control), as well as adjacent reference conditions. An additional experiment compared areas with and without vegetation planting following treatment. Negative effects of persistent heavy oiling on marsh vegetation, intertidal invertebrates, and shoreline erosion were observed. In areas without treatment, oiling conditions and negative effects for most marsh parameters did not considerably improve over two years. Both manual and mechanical treatment were effective at improving oiling conditions and vegetation characteristics, beginning the recovery process, though recovery was not complete by two years. Mechanical treatment had additional negative effects of mixing oil into the marsh soils and further accelerating erosion. Manual treatment appeared to strike the right balance between improving oiling and habitat conditions while not causing additional detrimental effects. However, even with these improvements, marsh periwinkle snails showed minimal signs of recovery through two years, suggesting that some ecosystem components may lag vegetation recovery. Planting following treatment quickened vegetation recovery and reduced shoreline erosion. Faced with comparable marsh oiling in the future, we would recommend manual treatment followed by planting. We caution against the use of intensive treatment methods with lesser marsh oiling. Oiled controls (no treatment “set-asides”) are essential for judging marsh treatment effectiveness and ecological effects; we recommend their use when applying intensive treatment methods. PMID:26200349

[Application of chemical ecology in controlling marine fouling organisms].

PubMed

Fang, Fang; Yan, Tao; Liu, Qing

2005-10-01

Many marine organisms can produce secondary metabolites beneficial to the protection of marine environments against fouling, and thus, applying chemo-ecological methods to extract the natural antifoulants from marine organisms to resolve the problems relevant to marine fouling is a new thinking in resent years. Its aim is to search for high efficient and non-toxic antifoulants to replace the existing chemically synthetic ones which are unfortunately found to have widespread toxic effects on marine environment. Although we know few about the antifouling mechanisms of secondary metabolites, many natural products have been proved to have antifouling activity. Therefore, basic and applied researches on the ecological roles of these natural compounds, their action mechanisms, coating compatibility, controlled release, and field test are required in the future.

Promoting Experimental Problem-solving Ability in Sixth-grade Students Through Problem-oriented Teaching of Ecology: Findings of an intervention study in a complex domain

NASA Astrophysics Data System (ADS)

Roesch, Frank; Nerb, Josef; Riess, Werner

2015-03-01

Our study investigated whether problem-oriented designed ecology lessons with phases of direct instruction and of open experimentation foster the development of cross-domain and domain-specific components of experimental problem-solving ability better than conventional lessons in science. We used a paper-and-pencil test to assess students' abilities in a quasi-experimental intervention study utilizing a pretest/posttest control-group design (N = 340; average performing sixth-grade students). The treatment group received lessons on forest ecosystems consistent with the principle of education for sustainable development. This learning environment was expected to help students enhance their ecological knowledge and their theoretical and methodological experimental competencies. Two control groups received either the teachers' usual lessons on forest ecosystems or non-specific lessons on other science topics. We found that the treatment promoted specific components of experimental problem-solving ability (generating epistemic questions, planning two-factorial experiments, and identifying correct experimental controls). However, the observed effects were small, and awareness for aspects of higher ecological experimental validity was not promoted by the treatment.

Ecological effects of alternative fuel-reduction treatments: highlights of the National Fire and Fire Surrogate study (FFS)

Treesearch

James D. McIver; Scott L. Stephens; James K. Agee; Jamie Barbour; Ralph E. J. Boerner; Carl B. Edminster; Karen L. Erickson; Kerry L. Farris; Christopher J. Fettig; Carl E. Fiedler; Sally Haase; Stephen C. Hart; Jon E. Keeley; Eric E. Knapp; John F. Lehmkuhl; Jason J. Moghaddas; William Otrosina; Kenneth W. Outcalt; Dylan W. Schwilk; Carl N. Skinner; Thomas A. Waldrop; C. Phillip Weatherspoon; Daniel A. Yaussy; Andrew Youngblood; Steve Zack

2012-01-01

The 12-site National Fire and Fire Surrogate study (FFS) was a multivariate experiment that evaluated ecological consequences of alternative fuel-reduction treatments in seasonally dry forests of the US. Each site was a replicated experiment with a common design that compared an un-manipulated control, prescribed fire, mechanical and mechanical + fire treatments....

[Effects of rare earth elements on soil fauna community structure and their ecotoxicity to Holotrichia parallela].

PubMed

Li, Guiting; Jiang, Junqi; Chen, Jie; Zou, Yunding; Zhang, Xincai

2006-01-01

By the method of OECD filter paper contact, this paper studied the effects of applied rare earth elements on soil fauna community structure and their ecological toxicity to Holotrichia parallela in bean field. The results showed that there were no significant differences between the treatments and the control in soil fauna species, quantity of main species, and diversity index. Urgent and chronic toxic test showed that the differences between the treatments and the control were not significant. It was suggested that within the range of test dosages, rare earth elements had little ecological toxicity to Holotrichia parallela, and did not change the soil fauna community structure.

Deriving criteria to select arthropod species for laboratory tests to assess the ecological risks from cultivating arthropod-resistant genetically engineered crops.

PubMed

Romeis, Jörg; Raybould, Alan; Bigler, Franz; Candolfi, Marco P; Hellmich, Richard L; Huesing, Joseph E; Shelton, Anthony M

2013-01-01

Arthropods form a major part of the biodiversity in agricultural landscapes. Many species are valued because they provide ecosystem services, including biological control, pollination and decomposition, or because they are of conservation interest. Some arthropods reduce crop yield and quality, and conventional chemical pesticides, biological control agents and genetically engineered (GE) crops are used to control them. A common concern addressed in the ecological risk assessment (ERA) that precedes regulatory approval of these pest control methods is their potential to adversely affect valued non-target arthropods (NTAs). A key concept of ERA is early-tier testing using worst-case exposure conditions in the laboratory and surrogate test species that are most likely to reveal an adverse effect. If no adverse effects are observed in those species at high exposures, confidence of negligible ecological risk from the use of the pest control method is increased. From experience with chemical pesticides and biological control agents, an approach is proposed for selecting test species for early-tier ERA of GE arthropod-resistant crops. Surrogate species should be selected that most closely meet three criteria: (i) Potential sensitivity: species should be the most likely to be sensitive to the arthropod-active compound based on the known spectrum of activity of the active ingredient, its mode of action, and the phylogenetic relatedness of the test and target species; (ii) species should be representative of valued taxa or functional groups that are most likely to be exposed to the arthropod-active compound in the field; and (iii) Availability and reliability: suitable life-stages of the test species must be obtainable in sufficient quantity and quality, and validated test protocols must be available that allow consistent detection of adverse effects on ecologically relevant parameters. Our proposed approach ensures that the most suitable species are selected for testing and that the resulting data provide the most rigorous test of the risk hypothesis of no adverse effect in order to increase the quality and efficiency of ERAs for cultivation of GE crops. Copyright © 2012 Elsevier Ltd. All rights reserved.

[Ecologic factors and risk of rehospitalization of psychotic patients].

PubMed

Klusmann, D; Angermeyer, M C

1986-01-01

The present study investigates the relationship between ecological factors and the community tenure patients with functional psychoses. Data were gathered from the records of three psychiatric hospitals in the city of Hamburg. The analysis controls for the effects of sociodemographic variables and variables pertaining to the last impatient treatment. Variations in readmission rates can be explained by the latter to a certain extent, but only poorly by sociodemographic variables and hardly at all by ecological factors. These findings are discussed with respect to the methodological limitations of the study and as substantive results. Two lines of interpretation are offered. Firstly, equal readmission rates may have been caused by different sets of ecological factors; secondly, patients released from mental hospital may be relatively insusceptible to the impact of ecological factors.

Pesticides, A Scientists' Institute for Public Information Workbook.

ERIC Educational Resources Information Center

Dahlsten, Donald L.; And Others

This collection of articles emphasizes the need for care in the use of chemical pesticides. Economic and ecological implications of pest control are discussed, and data are given on the effectiveness and side effects of chemical insecticides. Alternative methods of control are proposed. The part that can be played by the public in decision making…

Biotic Invasions: Causes, Epidemiology, Global Consequences and Control

EPA Pesticide Factsheets

The module provides a link to an article in a series of articles in Issues in Ecology. This article presents information on biotic invaders, their destruction, controlling their detriment and the effects aquaculture is having on world fish supplies.

Understanding the side effects of classical biological control

Treesearch

Dean Pearson

2008-01-01

Classical biological control involves the use of imported natural enemies to suppress or control populations of the target pest species below an economically or ecologically relevant threshold. Biological control is a useful tool for mitigating the impacts of exotic invasive plants; however, its application is not without risk (see Carruthers and D’Antonio...

Application of control theory to dynamic systems simulation

NASA Technical Reports Server (NTRS)

Auslander, D. M.; Spear, R. C.; Young, G. E.

1982-01-01

The application of control theory is applied to dynamic systems simulation. Theory and methodology applicable to controlled ecological life support systems are considered. Spatial effects on system stability, design of control systems with uncertain parameters, and an interactive computing language (PARASOL-II) designed for dynamic system simulation, report quality graphics, data acquisition, and simple real time control are discussed.

Improved understanding of weed biological control safety and impact with chemical ecology: a review

USDA-ARS?s Scientific Manuscript database

We review chemical ecology literature as it relates to weed biological control and discuss how this means of controlling invasive plants could be enhanced by the consideration of several well established research developments. The interface between chemical ecology and weed biological control presen...

[Ecological carrying capacity and Chongming Island's ecological construction].

PubMed

Wang, Kaiyun; Zou, Chunjing; Kong, Zhenghong; Wang, Tianhou; Chen, Xiaoyong

2005-12-01

This paper overviewed the goals of Chongming Island's ecological construction and its background, analyzed the current eco-economic status and constraints of the Island, and put forward some scientific issues on its ecological construction. It was suggested that for the resources-saving and sustainable development of the Island, the researches on its ecological construction should be based on its ecological carrying capacity, fully take the regional characteristics into consideration, and refer the successful development modes at home and abroad. The carrying capacity study should ground on systemic and dynamic views, give a thorough evaluation of the Island's present carrying capacity, simulate its possible changes, and forecast its demands and risks. Operable countermeasures to promote the Island's carrying capacity should be worked out, new industry structure, population scale, and optimized distribution projects conforming to regional carrying capacity should be formulated, and effective ecological security alarming and control system should be built, with the aim of providing suggestions and strategic evidences for the decision-making of economic development and sustainable environmental resources use of the region.

Physical disturbance to ecological niches created by soil structure alters community composition of methanotrophs.

PubMed

Kumaresan, Deepak; Stralis-Pavese, Nancy; Abell, Guy C J; Bodrossy, Levente; Murrell, J Colin

2011-10-01

Aggregates of different sizes and stability in soil create a composite of ecological niches differing in terms of physico-chemical and structural characteristics. The aim of this study was to identify, using DNA-SIP and mRNA-based microarray analysis, whether shifts in activity and community composition of methanotrophs occur when ecological niches created by soil structure are physically perturbed. Landfill cover soil was subject to three treatments termed: 'control' (minimal structural disruption), 'sieved' (sieved soil using 2 mm mesh) and 'ground' (grinding using mortar and pestle). 'Sieved' and 'ground' soil treatments exhibited higher methane oxidation potentials compared with the 'control' soil treatment. Analysis of the active community composition revealed an effect of physical disruption on active methanotrophs. Type I methanotrophs were the most active methanotrophs in 'sieved' and 'ground' soil treatments, whereas both Type I and Type II methanotrophs were active in the 'control' soil treatment. The result emphasize that changes to a particular ecological niche may not result in an immediate change to the active bacterial composition and change in composition will depend on the ability of the bacterial communities to respond to the perturbation. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

Effects of biological control agents and exotic plant invasion on deer mouse populations

Treesearch

Yvette K. Ortega; Dean E. Pearson; Kevin S. McKelvey

2004-01-01

Exotic insects are commonly introduced as biological control agents to reduce densities of invasive exotic plants. Although current biocontrol programs for weeds take precautions to minimize ecological risks, little attention is paid to the potential nontarget effects of introduced food subsidies on native consumers. Previous research demonstrated that two gall flies (...

Geographical and Temporal Body Size Variation in a Reptile: Roles of Sex, Ecology, Phylogeny and Ecology Structured in Phylogeny

PubMed Central

Aragón, Pedro; Fitze, Patrick S.

2014-01-01

Geographical body size variation has long interested evolutionary biologists, and a range of mechanisms have been proposed to explain the observed patterns. It is considered to be more puzzling in ectotherms than in endotherms, and integrative approaches are necessary for testing non-exclusive alternative mechanisms. Using lacertid lizards as a model, we adopted an integrative approach, testing different hypotheses for both sexes while incorporating temporal, spatial, and phylogenetic autocorrelation at the individual level. We used data on the Spanish Sand Racer species group from a field survey to disentangle different sources of body size variation through environmental and individual genetic data, while accounting for temporal and spatial autocorrelation. A variation partitioning method was applied to separate independent and shared components of ecology and phylogeny, and estimated their significance. Then, we fed-back our models by controlling for relevant independent components. The pattern was consistent with the geographical Bergmann's cline and the experimental temperature-size rule: adults were larger at lower temperatures (and/or higher elevations). This result was confirmed with additional multi-year independent data-set derived from the literature. Variation partitioning showed no sex differences in phylogenetic inertia but showed sex differences in the independent component of ecology; primarily due to growth differences. Interestingly, only after controlling for independent components did primary productivity also emerge as an important predictor explaining size variation in both sexes. This study highlights the importance of integrating individual-based genetic information, relevant ecological parameters, and temporal and spatial autocorrelation in sex-specific models to detect potentially important hidden effects. Our individual-based approach devoted to extract and control for independent components was useful to reveal hidden effects linked with alternative non-exclusive hypothesis, such as those of primary productivity. Also, including measurement date allowed disentangling and controlling for short-term temporal autocorrelation reflecting sex-specific growth plasticity. PMID:25090025

Impacts of terracing on soil erosion control and crop yield in two agro-ecological zones of Rwanda

NASA Astrophysics Data System (ADS)

Rutebuka, Jules; Ryken, Nick; Uwimanzi, Aline; Nkundwakazi, Olive; Verdoodt, Ann

2017-04-01

Soil erosion remains a serious limiting factor to the agricultural production in Rwanda. Terracing has been widely adopted in many parts of the country in the past years, but its effectiveness is not yet known. Besides the standard radical (bench) terraces promoted by the government, also progressive terraces (with living hedges) become adopted mainly by the farmers. The aim of this study was to measure short-term (two consecutive rainy seasons 2016A and 2016B) run-off and soil losses for existing radical (RT) and progressive (PT) terraces versus non-protected (NP) fields using erosion plots installed in two agro-ecological zones, i.e. Buberuka highlands (site Tangata) and Eastern plateau (site Murehe) and determine their impacts on soil fertility and crop production. The erosion plot experiment started with a topsoil fertility assessment and during the experiment, maize was grown as farmer's cropping preference in the area. Runoff data were captured after each rainfall event and the collected water samples were dried to determine soil loss. Both erosion control measures reduced soil losses in Tangata, with effectiveness indices ranging from 43 to 100% when compared to the NP plots. RT showed the highest effectiveness, especially in season A. In Murehe, RT minimized runoff and soil losses in both seasons. Yet, the PT were largely inefficient, leading to soil losses exceeding those on the NP plots (ineffectiveness index of -78% and -65% in season A and B, respectively). Though topsoil fertility assessment in the erosion plots showed that the soil quality parameters were significantly higher in RT and NP plots compared to the PT plots on both sites, maize grain yield was not correlated with the physical effectiveness of the erosion control measures. Finally, the effectiveness of soil erosion control measures as well as their positive impacts on soil fertility and production differ not only by terracing type but also by agro-ecological zone and the management or maintenance adopted by farmers. Terracing should be complemented by continuous fertility amendments (organic material inputs), use of improved agronomic and management practices considering agro-ecological zone conditions. In general, radical terracing was found to be the most effective soil erosion control measure on both sites.

Man as the main component of the closed ecological system of the spacecraft or planetary station.

PubMed

Parin, V V; Adamovich, B A

1968-01-01

Current life-support systems of the spacecraft provide human requirements for food, water and oxygen only. Advanced life-support systems will involve man as their main component and will ensure completely his material and energy requirements. The design of individual components of such systems will assure their entire suitability and mutual control effects. Optimization of the performance of the crew and ecological system, on the basis of the information characterizing their function, demands efficient methods of collection and treatment of the information obtained through wireless recording of physiological parameters and their automatic treatment. Peculiarities of interplanetary missions and planetary stations make it necessary to conform the schedule of physiological recordings with the work-and-rest cycle of the space crew and inertness of components of the ecological system, especially of those responsible for oxygen regeneration. It is rational to model ecological systems and their components, taking into consideration the correction effect of the information on the health conditions and performance of the crewmen. Wide application of physiological data will allow the selection of optimal designs and sharply increase reliability of ecological systems.

Ecology, Epidemiology and Disease Management of Ralstonia syzygii in Indonesia.

PubMed

Safni, Irda; Subandiyah, Siti; Fegan, Mark

2018-01-01

Ralstonia solanacearum species complex phylotype IV strains, which have been primarily isolated from Indonesia, Australia, Japan, Korea, and Malaysia, have undergone recent taxonomic and nomenclatural changes to be placed in the species Ralstonia syzygii . This species contains three subspecies; Ralstonia syzygii subsp. syzygii , a pathogen causing Sumatra disease of clove trees in Indonesia, Ralstonia syzygii subsp. indonesiensis , the causal pathogen of bacterial wilt disease on a wide range of host plants, and Ralstonia syzygii subsp. celebesensis , the causal pathogen of blood disease on Musa spp. In Indonesia, these three subspecies have devastated the cultivation of susceptible host plants which have high economic value. Limited knowledge on the ecology and epidemiology of the diseases has hindered the development of effective control strategies. In this review, we provide insights into the ecology, epidemiology and disease control of these three subspecies of Ralstonia syzygii .

Aquatic Nuisance Sp[ecies Research Program. Ecological Impacts of Suckermouth Catfishes (Loricariidae) in North America: A Conceptual Model. Volume 14-1, March 2014

DTIC Science & Technology

2014-03-01

not provide effective control. Most tropical fi sh commercially available to hobbyists have recommended temperature requirements > 20 oC (e.g...at 10-12 oC (RR-C). This suggests lower lethal temperatures of 12-14 oC, but laboratory studies by the Florida Fish and Wildlife Conservation...55(5): 58-60. Flecker, A.S. 1992. Fish trophic guilds and the structure of a tropical stream: Weak vs. strong indirect effects . Ecology 73

Association between forestry ecological engineering and dust weather in Inner Mongolia: A panel study

NASA Astrophysics Data System (ADS)

Jixia, Huang; Qibin, Zhang; Jing, Tan; Depeng, Yue; Quansheng, Ge

2018-04-01

Forestry ecological engineering projects in Western China include the Three-North Shelter Forest Project (TNSFP), the Natural Forest Protection Project (NFPP), the Grain for Green Project (GGP) and the Beijing-Tianjin Sandstorm Source Project (BTSSP). Such projects play an important role in the control of dust weather in Western China. In this research, data on the frequency of sandstorms, sand-blowing and dust-floating weather, the area of four forestry ecological engineering projects, wind, rainfall and vegetation coverage from 2000 to 2010 were collected based on the unit of prefecture-level cities in Inner Mongolia. The panel-data model was used to analyze the quantitative association between forestry ecological engineering and dust weather. The results indicate that wind has a strong promotional effect on dust weather, while forestry ecological engineering and rainfall have a containment effect. In addition, the impacts of the four studied forestry ecological engineering projects on dust weather differ. For every increase of 1000 km2 in the Three-North Shelter Forest Project, the annual number of days of sandstorm weather decreased by 4 days. Similarly, for every increase of 1000 km2 in the Beijing-Tianjin Sandstorm Source Project, the sand-blowing weather decreased by 4.4 days annually. In addition, NFPP and GGP have a more obvious inhibitory effect on the dust-floating weather.

40 CFR 52.200 - Original identification of plan section.

Code of Federal Regulations, 2010 CFR

2010-07-01

... were held was submitted by the State Department of Pollution Control and Ecology on January 25, 1972. (Non-regulatory) (2) State Department of Pollution Control and Ecology letter outlining projected... submitted by the Department of Pollution Control and Ecology on July 7, 1972. (4) June 27, 1975, letter from...

40 CFR 52.200 - Original identification of plan section.

Code of Federal Regulations, 2011 CFR

2011-07-01

... were held was submitted by the State Department of Pollution Control and Ecology on January 25, 1972. (Non-regulatory) (2) State Department of Pollution Control and Ecology letter outlining projected... submitted by the Department of Pollution Control and Ecology on July 7, 1972. (4) June 27, 1975, letter from...

40 CFR 147.200 - State-administered program-Class I, III, IV, and V wells.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the program administered by the Arkansas Department of Pollution Control and Ecology approved by EPA... Code, Department of Pollution Control and Ecology, promulgated January 22, 1982; (4) General Rule and... Management Code, Department of Pollution Control and Ecology, promulgated August 21, 1981. (b) The Memorandum...

40 CFR 147.200 - State-administered program-Class I, III, IV, and V wells.

Code of Federal Regulations, 2011 CFR

2011-07-01

... the program administered by the Arkansas Department of Pollution Control and Ecology approved by EPA... Code, Department of Pollution Control and Ecology, promulgated January 22, 1982; (4) General Rule and... Management Code, Department of Pollution Control and Ecology, promulgated August 21, 1981. (b) The Memorandum...

40 CFR 282.53 - Arkansas State-Administered Program.

Code of Federal Regulations, 2011 CFR

2011-07-01

... administered by the Arkansas Department of Pollution Control and Ecology, was approved by EPA pursuant to 42 U... Pollution Control and Ecology, 8001 National Drive, Little Rock, AR 72219-8913. (1) State statutes and... include: (1) Arkansas Department of Pollution Control and Ecology Regulation Number 12—Storage Tank...

40 CFR 282.53 - Arkansas State-Administered Program.

Code of Federal Regulations, 2010 CFR

2010-07-01

... administered by the Arkansas Department of Pollution Control and Ecology, was approved by EPA pursuant to 42 U... Pollution Control and Ecology, 8001 National Drive, Little Rock, AR 72219-8913. (1) State statutes and... include: (1) Arkansas Department of Pollution Control and Ecology Regulation Number 12—Storage Tank...

40 CFR 147.200 - State-administered program-Class I, III, IV, and V wells.

Code of Federal Regulations, 2014 CFR

2014-07-01

... the program administered by the Arkansas Department of Pollution Control and Ecology approved by EPA... Code, Department of Pollution Control and Ecology, promulgated January 22, 1982; (4) General Rule and... Management Code, Department of Pollution Control and Ecology, promulgated August 21, 1981. (b) The Memorandum...

40 CFR 147.200 - State-administered program-Class I, III, IV, and V wells.

Code of Federal Regulations, 2012 CFR

2012-07-01

... the program administered by the Arkansas Department of Pollution Control and Ecology approved by EPA... Code, Department of Pollution Control and Ecology, promulgated January 22, 1982; (4) General Rule and... Management Code, Department of Pollution Control and Ecology, promulgated August 21, 1981. (b) The Memorandum...

40 CFR 147.200 - State-administered program-Class I, III, IV, and V wells.

Code of Federal Regulations, 2013 CFR

2013-07-01

... the program administered by the Arkansas Department of Pollution Control and Ecology approved by EPA... Code, Department of Pollution Control and Ecology, promulgated January 22, 1982; (4) General Rule and... Management Code, Department of Pollution Control and Ecology, promulgated August 21, 1981. (b) The Memorandum...

40 CFR 282.53 - Arkansas State-Administered Program.

Code of Federal Regulations, 2013 CFR

2013-07-01

... administered by the Arkansas Department of Pollution Control and Ecology, was approved by EPA pursuant to 42 U... Pollution Control and Ecology, 8001 National Drive, Little Rock, AR 72219-8913. (1) State statutes and... include: (1) Arkansas Department of Pollution Control and Ecology Regulation Number 12—Storage Tank...

40 CFR 282.53 - Arkansas State-Administered Program.

Code of Federal Regulations, 2014 CFR

2014-07-01

... administered by the Arkansas Department of Pollution Control and Ecology, was approved by EPA pursuant to 42 U... Pollution Control and Ecology, 8001 National Drive, Little Rock, AR 72219-8913. (1) State statutes and... include: (1) Arkansas Department of Pollution Control and Ecology Regulation Number 12—Storage Tank...

40 CFR 282.53 - Arkansas State-Administered Program.

Code of Federal Regulations, 2012 CFR

2012-07-01

... administered by the Arkansas Department of Pollution Control and Ecology, was approved by EPA pursuant to 42 U... Pollution Control and Ecology, 8001 National Drive, Little Rock, AR 72219-8913. (1) State statutes and... include: (1) Arkansas Department of Pollution Control and Ecology Regulation Number 12—Storage Tank...

Review: Nutritional ecology of heavy metals.

PubMed

Hejna, M; Gottardo, D; Baldi, A; Dell'Orto, V; Cheli, F; Zaninelli, M; Rossi, L

2018-01-08

The aim of this review is to focus the attention on the nutrition ecology of the heavy metals and on the major criticisms related to the heavy metals content in animal feeds, manure, soil and animal-origin products. Heavy metals are metallic elements that have a high density that have progressively accumulated in the food chain with negative effects for human health. Some metals are essential (Fe, I, Co, Zn, Cu, Mn, Mo, Se) to maintain various physiological functions and are usually added as nutritional additives in animal feed. Other metals (As, Cd, F, Pb, Hg) have no established biological functions and are considered as contaminants/undesirable substances. The European Union adopted several measures in order to control their presence in the environment, as a result of human activities such as: farming, industry or food processing and storage contamination. The control of the animal input could be an effective strategy to reduce human health risks related to the consumption of animal-origin products and the environmental pollution by manure. Different management of raw materials and feed, animal species as well as different legal limits can influence the spread of heavy metals. To set up effective strategies against heavy metals the complex interrelationships in rural processes, the widely variability of farming practices, the soil and climatic conditions must be considered. Innovative and sustainable approaches have discussed for the heavy metal nutrition ecology to control the environmental pollution from livestock-related activities.

Development paths of China's agricultural Pharmaceutical industry under Eco-agriculture background.

PubMed

Li, Jinkai; Gong, Liutang; Ji, Xi; Zhang, Jin; Miao, Pei

2014-07-01

Using pesticides has double effects. On one hand, it contributes to pests control and regulates the growth of crops; On the other hand, it does harm to the environment. To develop ecological agriculture should not only emphasize the output level of agriculture to pursuit of economic efficiency, but also need to keep the ecological environment protected and focus on the social benefits during the development of the industry. As a large agricultural country in the world, China is vigorously promoting the development of ecological agriculture, which is bound to put forward to developing the pesticide industry and green ecological development requirements to promote the transformation and upgrading of agricultural pharmaceutical industry. This paper discusses the mechanism of pesticide pollution on the ecological environment and analyzes China's agricultural problems in the pharmaceutical industry. Then study on the development of Chinese green pesticides and try to find the proper paths of agricultural pharmaceutical to achieve industrial upgrading.

Sewage impacts coral reefs at multiple levels of ecological organization.

PubMed

Reopanichkul, Pasinee; Schlacher, Thomas A; Carter, R W; Worachananant, Suchai

2009-09-01

Against a backdrop of rising sea temperatures and ocean acidification which pose global threats to coral reefs, excess nutrients and turbidity continue to be significant stressors at regional and local scales. Because interventions usually require local data on pollution impacts, we measured ecological responses to sewage discharges in Surin Marine Park, Thailand. Wastewater disposal significantly increased inorganic nutrients and turbidity levels, and this degradation in water quality resulted in substantial ecological shifts in the form of (i) increased macroalgal density and species richness, (ii) lower cover of hard corals, and (iii) significant declines in fish abundance. Thus, the effects of nutrient pollution and turbidity can cascade across several levels of ecological organization to change key properties of the benthos and fish on coral reefs. Maintenance or restoration of ecological reef health requires improved wastewater management and run-off control for reefs to deliver their valuable ecosystems services.

Methods for control of tick vectors of Lyme Borreliosis

USGS Publications Warehouse

Jaenson, T.G.T.; Fish, D.; Ginsberg, H.S.; Gray, J.S.; Mather, T.N.; Piesman, J.

1991-01-01

During the IVth International Conference on Lyme Borreliosis in Stockholm, 1990, a workshop on control of Lyme disease vectors briefly reviewed: basic ecological principles for tick control; biocontrol of ticks; chemical control, including the use of repellents and use of permethrin-treated rodent nest material; tick control by habitat modification; and reduction of tick host availability. It was concluded that, although much research work remains, Lyme borreliosis is to a large extent a preventable infection. Avoidance of heavily tick-infested areas, personal protection using proper clothing, and prompt removal of attached ticks remain the most effective protective measures. Many other prophylactic measures are available and could be efficiently integrated into schemes to reduce the abundance of vectors. However, since the ecology of the infection varies greatly between different localities it may be necessary to apply different combinations of control methods in different endemic regions.

Enhancing the effectiveness of biological control programs of invasive species through a more comprehensive pest management approach.

PubMed

DiTomaso, Joseph M; Van Steenwyk, Robert A; Nowierski, Robert M; Vollmer, Jennifer L; Lane, Eric; Chilton, Earl; Burch, Patrick L; Cowan, Phil E; Zimmerman, Kenneth; Dionigi, Christopher P

2017-01-01

Invasive species are one of the greatest economic and ecological threats to agriculture and natural areas in the US and the world. Among the available management tools, biological control provides one of the most economical and long-term effective strategies for managing widespread and damaging invasive species populations of nearly all taxa. However, integrating biological control programs in a more complete integrated pest management approach that utilizes increased information and communication, post-release monitoring, adaptive management practices, long-term stewardship strategies, and new and innovative ecological and genetic technologies can greatly improve the effectiveness of biological control. In addition, expanding partnerships among relevant national, regional, and local agencies, as well as academic scientists and land managers, offers far greater opportunities for long-term success in the suppression of established invasive species. In this paper we direct our recommendations to federal agencies that oversee, fund, conduct research, and develop classical biological control programs for invasive species. By incorporating these recommendations into adaptive management strategies, private and public land managers will have far greater opportunities for long-term success in suppression of established invasive species. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Characterization of the ecological interactions of Roundup Ready 2 Yield® soybean, MON 89788, for use in ecological risk assessment

PubMed Central

Horak, Michael J; Rosenbaum, Eric W; Phillips, Samuel L; Kendrick, Daniel L; Carson, David; Clark, Pete L; Nickson, Thomas E

2015-01-01

Abstract As part of an ecological risk assessment, Roundup Ready 2 Yield® soybean (MON 89788) was compared to a conventional control soybean variety, A3244, for disease and arthropod damage, plant response to abiotic stress and cold, effects on succeeding plant growth (allelopathic effects), plant response to a bacterial symbiont, and effects on the ability of seed to survive and volunteer in a subsequent growing season. Statistically significant differences between MON 89788 and A3244 were considered in the context of the genetic variation known to occur in soybean and were assessed for their potential impact on plant pest (weed) potential and adverse environmental impact. The results of these studies revealed no effects of the genetic modification that would result in increased pest potential or adverse environmental impact of MON 89788 compared with A3244. This paper illustrates how such characterization studies conducted in a range of environments where the crop is grown are used in an ecological risk assessment of the genetically modified (GM) crop. Furthermore, risk assessors and decision makers use this information when deciding whether to approve a GM crop for cultivation in—or grain import into—their country. PMID:26177011

Supporting Multiple Cognitive Processing Styles Using Tailored Support Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tuan Q. Tran; Karen M. Feigh; Amy R. Pritchett

According to theories of cognitive processing style or cognitive control mode, human performance is more effective when an individual’s cognitive state (e.g., intuition/scramble vs. deliberate/strategic) matches his/her ecological constraints or context (e.g., utilize intuition to strive for a "good-enough" response instead of deliberating for the "best" response under high time pressure). Ill-mapping between cognitive state and ecological constraints are believed to lead to degraded task performance. Consequently, incorporating support systems which are designed to specifically address multiple cognitive and functional states e.g., high workload, stress, boredom, and initiate appropriate mitigation strategies (e.g., reduce information load) is essential to reduce plantmore » risk. Utilizing the concept of Cognitive Control Models, this paper will discuss the importance of tailoring support systems to match an operator's cognitive state, and will further discuss the importance of these ecological constraints in selecting and implementing mitigation strategies for safe and effective system performance. An example from the nuclear power plant industry illustrating how a support system might be tailored to support different cognitive states is included.« less

Effects of anthropogenic noise on endocrine and reproductive function in White's treefrog, Litoria caerulea

PubMed Central

Kaiser, Kristine; Devito, Julia; Jones, Caitlin G.; Marentes, Adam; Perez, Rachel; Umeh, Lisa; Weickum, Regina M.; McGovern, Kathryn E.; Wilson, Emma H.; Saltzman, Wendy

2015-01-01

Urbanization is a major driver of ecological change and comes with a suite of habitat modifications, including alterations to the local temperature, precipitation, light and noise regimes. Although many recent studies have investigated the behavioural and ecological ramifications of urbanization, physiological work in this area has lagged. We tested the hypothesis that anthropogenic noise is a stressor for amphibians and that chronic exposure to such noise leads to reproductive suppression. In the laboratory, we exposed male White's treefrogs, Litoria caerulea, to conspecific chorus noise either alone or coupled with pre-recorded traffic noise nightly for 1 week. Frogs presented with anthropogenic noise had significantly higher circulating concentrations of corticosterone and significantly decreased sperm count and sperm viability than did control frogs. These results suggest that in addition to having behavioural and ecological effects, anthropogenic change might alter physiology and Darwinian fitness. Future work should integrate disparate fields such as behaviour, ecology and physiology to elucidate fully organisms’ responses to habitat change. PMID:27293682

Salt marsh-mangrove ecotones: using structural gradients to investigate the effects of woody plant encroachment on plant-soil interactions and ecosystem carbon pools

USGS Publications Warehouse

Yando, Erik S.; Osland, Michael J.; Willis, Jonathan M; Day, Richard H.; Krauss, Ken W.; Hester, Mark W.

2016-01-01

Synthesis: Our results indicate that the ecological implications of woody plant encroachment in tidal saline wetlands are dependent upon precipitation controls of plant–soil interactions. Although the above-ground effects of mangrove expansion are consistently large, below-ground influences of mangrove expansion appear to be greatest along low-rainfall coasts where salinities are high and marshes being replaced are carbon poor and dominated by succulent plants. Collectively, these findings complement those from terrestrial ecosystems and reinforce the importance of considering rainfall and plant–soil interactions within predictions of the ecological effects of woody plant encroachment.

The '333' integrated strategy for effective pollution control and its application to the heavily polluted Jialu River in north China.

PubMed

Huang, Yu; Sun, Jie; Li, Aimin; Xie, Xianchuan

2018-05-01

In this study, an integrated approach named the '333' strategy was applied to pollution control in the Jialu River, in northern China, which is heavily burdened with anthropogenic pollution. Due to a deficiency of the natural ecological inflow, the Jialu River receives predominantly industrial and municipal effluent. The '333' strategy is composed of three steps of pollution control including industrial point-source pollution control, advanced treatment of municipal wastewater, and ecological restoration; three increased stringency emission standards; and three stages of reclamation. Phase 1 of the '333' strategy focuses on industrial point-source pollution control; phase 2 aims to harness municipal wastewater and minimize sewage effluents using novel techniques for advanced water purification; phase 3 of the '333' strategy focuses on the further purification of effluents flowing into Jialu River with the employment of an engineering-based ecological restoration project. The application of the '333' strategy resulted in the development of novel techniques for water purification including modified magnetic resins (NDMP resin), a two-stage internal circulation anaerobic reactor (IC reactor) and an ecological restoration system. The results indicate that water quality in the river was significantly improved, with increased concentrations of dissolved oxygen (DO), as well as reduction of COD by 42.8% and NH 3 -N by 61.4%. In addition, it was observed that the total population of phytoplankton in treated river water notably increased from only one prior to restoration to 8 following restoration. This system also provides a tool for pollution control of other similar industrial and anthropogenic source polluted rivers.

Phosphorus retention in stormwater control structures across streamflow in urban and suburban watersheds

EPA Science Inventory

Recent studies have shown that stormwater control measures (SCMs) are less effective at retaining phosphorus (P) than nitrogen. We compared P retention between two urban/suburban SCMs and their adjacent restored stream reaches at the Baltimore Long-Term Ecological Study (LTER) s...

Model of continual metabolism species for estimating stability of CELSS and natural ecosystems

NASA Astrophysics Data System (ADS)

Bartsev, S. I.

Estimation of stability range of natural and man-made ecosystems is necessary for effective control of them However traditional ecological models usually underestimate stability of real ecosystems It takes place due to the usage of fixed stoichiometry model of metabolism The objective is in creating theoretical and mathematical models for adequate description of both man-made and natural ecological systems A concept of genetically fixed but metabolically flexible species is considered in the paper According to the concept the total flow of matter through ecological system is supported at almost constant level depending on energy income by flexibility of metabolic organization of genetic species It is shown introducing continual metabolism species extends the range of stability making its estimation more adequate to real ecological systems

Chemical ecology of animal and human pathogen vectors in a changing global climate.

PubMed

Pickett, John A; Birkett, Michael A; Dewhirst, Sarah Y; Logan, James G; Omolo, Maurice O; Torto, Baldwyn; Pelletier, Julien; Syed, Zainulabeuddin; Leal, Walter S

2010-01-01

Infectious diseases affecting livestock and human health that involve vector-borne pathogens are a global problem, unrestricted by borders or boundaries, which may be exacerbated by changing global climate. Thus, the availability of effective tools for control of pathogen vectors is of the utmost importance. The aim of this article is to review, selectively, current knowledge of the chemical ecology of pathogen vectors that affect livestock and human health in the developed and developing world, based on key note lectures presented in a symposium on "The Chemical Ecology of Disease Vectors" at the 25th Annual ISCE meeting in Neuchatel, Switzerland. The focus is on the deployment of semiochemicals for monitoring and control strategies, and discusses briefly future directions that such research should proceed along, bearing in mind the environmental challenges associated with climate change that we will face during the 21st century.

Ecology, Epidemiology and Disease Management of Ralstonia syzygii in Indonesia

PubMed Central

Safni, Irda; Subandiyah, Siti; Fegan, Mark

2018-01-01

Ralstonia solanacearum species complex phylotype IV strains, which have been primarily isolated from Indonesia, Australia, Japan, Korea, and Malaysia, have undergone recent taxonomic and nomenclatural changes to be placed in the species Ralstonia syzygii. This species contains three subspecies; Ralstonia syzygii subsp. syzygii, a pathogen causing Sumatra disease of clove trees in Indonesia, Ralstonia syzygii subsp. indonesiensis, the causal pathogen of bacterial wilt disease on a wide range of host plants, and Ralstonia syzygii subsp. celebesensis, the causal pathogen of blood disease on Musa spp. In Indonesia, these three subspecies have devastated the cultivation of susceptible host plants which have high economic value. Limited knowledge on the ecology and epidemiology of the diseases has hindered the development of effective control strategies. In this review, we provide insights into the ecology, epidemiology and disease control of these three subspecies of Ralstonia syzygii. PMID:29662468

Population-level compensation impedes biological control of an invasive forb and indirect release of a native grass

Treesearch

Yvette K. Ortega; Dean E. Pearson; Lauren P. Waller; Nancy J. Sturdevant; John L. Maron

2012-01-01

The intentional introduction of specialist insect herbivores for biological control of exotic weeds provides ideal but understudied systems for evaluating important ecological concepts related to top-down control, plant compensatory responses, indirect effects, and the influence of environmental context on these processes. Centaurea stoebe (spotted knapweed) is a...

Biological control via "ecological" damping: An approach that attenuates non-target effects.

PubMed

Parshad, Rana D; Quansah, Emmanuel; Black, Kelly; Beauregard, Matthew

2016-03-01

In this work we develop and analyze a mathematical model of biological control to prevent or attenuate the explosive increase of an invasive species population, that functions as a top predator, in a three-species food chain. We allow for finite time blow-up in the model as a mathematical construct to mimic the explosive increase in population, enabling the species to reach "disastrous", and uncontrollable population levels, in a finite time. We next improve the mathematical model and incorporate controls that are shown to drive down the invasive population growth and, in certain cases, eliminate blow-up. Hence, the population does not reach an uncontrollable level. The controls avoid chemical treatments and/or natural enemy introduction, thus eliminating various non-target effects associated with such classical methods. We refer to these new controls as "ecological damping", as their inclusion dampens the invasive species population growth. Further, we improve prior results on the regularity and Turing instability of the three-species model that were derived in Parshad et al. (2014). Lastly, we confirm the existence of spatiotemporal chaos. Copyright © 2016 Elsevier Inc. All rights reserved.

Quantifying the ecological success of a community-based wildlife conservation area in Tanzania.

PubMed

Lee, Derek E; Bond, Monica L

2018-04-03

In Tanzania, community-based natural resource management of wildlife occurs through the creation of Wildlife Management Areas (WMAs). WMAs consist of multiple villages designating land for wildlife conservation, and sharing a portion of subsequent tourism revenues. Nineteen WMAs are currently operating, encompassing 7% of Tanzania's land area, with 19 more WMAs planned. The ecological success or failure of WMAs for wildlife conservation has yet to be quantified. We defined ecological success in this case as significantly greater densities of wildlife and significantly lower densities of livestock in the WMA relative to the control site, after the WMA was established. We used 4 years of distance sampling surveys conducted 6 times per year for wild and domestic ungulates to quantify wildlife and livestock densities before and after the establishment and implementation of management efforts at Randilen WMA, relative to a control site on adjacent land of similar vegetation and habitat types. We documented similarity between the sites before WMA establishment, when both sites were managed by the same authority. After WMA establishment, we documented significantly higher densities of resident wildlife (giraffes and dik-diks) and lower densities of cattle in the WMA, relative to the control site, indicating short-term ecological success. Continued monitoring is necessary to determine longer-term effects, and to evaluate management decisions.

Campylobacter in poultry: filling an ecological niche.

PubMed

Lee, Margie D; Newell, Diane G

2006-03-01

Epidemiological studies indicate that Campylobacter species may be responsible for the majority of cases of sporadic gastroenteritis in humans. These studies also suggest that poultry may be one of the most common sources of the bacteria for humans. Campylobacter and related genera in the family Campylobacteraceae are oral and intestinal commensals of vertebrates and some nonvertebrates, a characteristic that complicates rational approaches to controlling Campylobacter contamination of poultry. This review will discuss the phylogeny, genomics, and physiology of campylobacters with the intention of revealing how these organisms have evolved to fill their intestinal ecological niche in poultry and how their physiology must be understood in order to enact effective control strategies.

Twenty-five years of ecological recovery of East Fork Poplar Creek: review of environmental problems and remedial actions.

PubMed

Loar, James M; Stewart, Arthur J; Smith, John G

2011-06-01

In May 1985, a National Pollutant Discharge Elimination System permit was issued for the Department of Energy's Y-12 National Security Complex (Y-12 Complex) in Oak Ridge, Tennessee, USA, allowing discharge of effluents to East Fork Poplar Creek (EFPC). The effluents ranged from large volumes of chlorinated once-through cooling water and cooling tower blow-down to smaller discharges of treated and untreated process wastewaters, which contained a mixture of heavy metals, organics, and nutrients, especially nitrates. As a condition of the permit, a Biological Monitoring and Abatement Program (BMAP) was developed to meet two major objectives: demonstrate that the established effluent limitations were protecting the classified uses of EFPC, and document the ecological effects resulting from implementing a Water Pollution Control Program at the Y-12 Complex. The second objective is the primary focus of the other papers in this special series. This paper provides a history of pollution and the remedial actions that were implemented; describes the geographic setting of the study area; and characterizes the physicochemical attributes of the sampling sites, including changes in stream flow and temperature that occurred during implementation of the BMAP. Most of the actions taken under the Water Pollution Control Program were completed between 1986 and 1998, with as many as four years elapsing between some of the most significant actions. The Water Pollution Control Program included constructing nine new wastewater treatment facilities and implementation of several other pollution-reducing measures, such as a best management practices plan; area-source pollution control management; and various spill-prevention projects. Many of the major actions had readily discernable effects on the chemical and physical conditions of EFPC. As controls on effluents entering the stream were implemented, pollutant concentrations generally declined and, at least initially, the volume of water discharged from the Y-12 Complex declined. This reduction in discharge was of ecological concern and led to implementation of a flow management program for EFPC. Implementing flow management, in turn, led to substantial changes in chemical and physical conditions of the stream: stream discharge nearly doubled and stream temperatures decreased, becoming more similar to those in reference streams. While water quality clearly improved, meeting water quality standards alone does not guarantee protection of a waterbody's biological integrity. Results from studies on the ecological changes stemming from pollution-reduction actions, such as those presented in this series, also are needed to understand how best to restore or protect biological integrity and enhance ecological recovery in stream ecosystems. With a better knowledge of the ecological consequences of their decisions, environmental managers can better evaluate alternative actions and more accurately predict their effects.

Twenty-Five Years of Ecological Recovery of East Fork Poplar Creek: Review of Environmental Problems and Remedial Actions

NASA Astrophysics Data System (ADS)

Loar, James M.; Stewart, Arthur J.; Smith, John G.

2011-06-01

In May 1985, a National Pollutant Discharge Elimination System permit was issued for the Department of Energy's Y-12 National Security Complex (Y-12 Complex) in Oak Ridge, Tennessee, USA, allowing discharge of effluents to East Fork Poplar Creek (EFPC). The effluents ranged from large volumes of chlorinated once-through cooling water and cooling tower blow-down to smaller discharges of treated and untreated process wastewaters, which contained a mixture of heavy metals, organics, and nutrients, especially nitrates. As a condition of the permit, a Biological Monitoring and Abatement Program (BMAP) was developed to meet two major objectives: demonstrate that the established effluent limitations were protecting the classified uses of EFPC, and document the ecological effects resulting from implementing a Water Pollution Control Program at the Y-12 Complex. The second objective is the primary focus of the other papers in this special series. This paper provides a history of pollution and the remedial actions that were implemented; describes the geographic setting of the study area; and characterizes the physicochemical attributes of the sampling sites, including changes in stream flow and temperature that occurred during implementation of the BMAP. Most of the actions taken under the Water Pollution Control Program were completed between 1986 and 1998, with as many as four years elapsing between some of the most significant actions. The Water Pollution Control Program included constructing nine new wastewater treatment facilities and implementation of several other pollution-reducing measures, such as a best management practices plan; area-source pollution control management; and various spill-prevention projects. Many of the major actions had readily discernable effects on the chemical and physical conditions of EFPC. As controls on effluents entering the stream were implemented, pollutant concentrations generally declined and, at least initially, the volume of water discharged from the Y-12 Complex declined. This reduction in discharge was of ecological concern and led to implementation of a flow management program for EFPC. Implementing flow management, in turn, led to substantial changes in chemical and physical conditions of the stream: stream discharge nearly doubled and stream temperatures decreased, becoming more similar to those in reference streams. While water quality clearly improved, meeting water quality standards alone does not guarantee protection of a waterbody's biological integrity. Results from studies on the ecological changes stemming from pollution-reduction actions, such as those presented in this series, also are needed to understand how best to restore or protect biological integrity and enhance ecological recovery in stream ecosystems. With a better knowledge of the ecological consequences of their decisions, environmental managers can better evaluate alternative actions and more accurately predict their effects.

Use of prism adaptation in children with unilateral brain lesion: Is it feasible?

PubMed

Riquelme, Inmaculada; Henne, Camille; Flament, Benoit; Legrain, Valéry; Bleyenheuft, Yannick; Hatem, Samar M

2015-01-01

Unilateral visuospatial deficits have been observed in children with brain damage. While the effectiveness of prism adaptation for treating unilateral neglect in adult stroke patients has been demonstrated previously, the usefulness of prism adaptation in a pediatric population is still unknown. The present study aims at evaluating the feasibility of prism adaptation in children with unilateral brain lesion and comparing the validity of a game procedure designed for child-friendly paediatric intervention, with the ecological task used for prism adaptation in adult patients. Twenty-one children with unilateral brain lesion randomly were assigned to a prism group wearing prismatic glasses, or a control group wearing neutral glasses during a bimanual task intervention. All children performed two different bimanual tasks on randomly assigned consecutive days: ecological tasks or game tasks. The efficacy of prism adaptation was measured by assessing its after-effects with visual open loop pointing (visuoproprioceptive test) and subjective straight-ahead pointing (proprioceptive test). Game tasks and ecological tasks produced similar after-effects. Prismatic glasses elicited a significant shift of visuospatial coordinates which was not observed in the control group. Prism adaptation performed with game tasks seems an effective procedure to obtain after-effects in children with unilateral brain lesion. The usefulness of repetitive prism adaptation sessions as a therapeutic intervention in children with visuospatial deficits and/or neglect, should be investigated in future studies. Copyright © 2015 Elsevier Ltd. All rights reserved.

Patients as Patches: Ecology and Epidemiology in Healthcare Environments.

PubMed

Lofgren, Eric T; Egizi, Andrea M; Fefferman, Nina H

2016-12-01

The modern healthcare system involves complex interactions among microbes, patients, providers, and the built environment. It represents a unique and challenging setting for control of the emergence and spread of infectious diseases. We examine an extension of the perspectives and methods from ecology (and especially urban ecology) to address these unique issues, and we outline 3 examples: (1) viewing patients as individual microbial ecosystems; (2) the altered ecology of infectious diseases specifically within hospitals; and (3) ecosystem management perspectives for infection surveillance and control. In each of these cases, we explore the accuracy and relevance of analogies to existing urban ecological perspectives, and we demonstrate a few of the potential direct uses of this perspective for altering research into the control of healthcare-associated infections. Infect Control Hosp Epidemiol. 2016;1507-1512.

Health risk assessment of heavy metals in fish and accumulation patterns in food web in the upper Yangtze River, China.

PubMed

Yi, Yujun; Tang, Caihong; Yi, Tieci; Yang, Zhifeng; Zhang, Shanghong

2017-11-01

This study aims to concern the distribution of As, Cr, Cd, Hg, Cu, Zn, Pb and Fe in surface sediment, zoobenthos and fishes, and quantify the accumulative ecological risk and human health risk of metals in river ecological system based on the field investigation in the upper Yangtze River. The results revealed high ecological risk of As, Cd, Cu, Hg, Zn and Pb in sediment. As and Cd in fish presented potential human health risk of metals by assessing integrated target hazard quotient results based on average and maximum concentrations, respectively. No detrimental health effects of heavy metals on humans were found by daily fish consumption. While, the total target hazard quotient (1.659) exceeding 1, it meant that the exposed population might experience noncarcinogenic health risks from the accumulative effect of metals. Ecological network analysis model was established to identify the transfer routes and quantify accumulative effects of metals on river ecosystem. Control analysis between compartments showed large predator fish firstly depended on the omnivorous fish. Accumulative ecological risk of metals indicated that zoobenthos had the largest metal propagation risk and compartments located at higher trophic levels were not easier affected by the external environment pollution. A potential accumulative ecological risk of heavy metal in the food web was quantified, and the noncarcinogenic health risk of fish consumption was revealed for the upper reach of the Yangtze River. Copyright © 2017 Elsevier Inc. All rights reserved.

[Interception Effect of Ecological Ditch on Nitrogen Transport in Agricultural Runoff in Subtropical China].

PubMed

Wang, Di; Li, Hong-fang; Liu, Feng; Wang, Yi; Zhong, Yuan-chun; He, Yang; Xiao, Run-fin; Wu, Jin-shui

2016-05-15

Interception effects of an ecological ditch, used to control agricultural non-point source pollution in subtropical China, on nitrogen transport in surface runoff were studied by monthly measuring the runoff volume and concentrations of ammonium nitrogen (NH₄⁺-N), nitrate nitrogen (NO₃⁻-N) and total nitrogen (TN) at the ditch inlet and outlet from 2013 to 2014. In addition, differences of NH₄⁺-N, NO₃⁻-N and TN removal were compared between 2013 and 2014. The results showed that the study ecological ditch worked effectively in N removal with average NH₄⁺-N, NO₃⁻-N and TN removal rates of 77.8%, 58.3%, and 48.7%; and their interception rates were 38.4, 59.6, and 171.1 kg · a⁻¹, respectively. The average proportion of NH₄⁺-N and NO₃⁻-N in TN was 47.5% at inlet, and 33.6% at outlet, which was significantly lower than that at inlet (P < 0.01). All hydrophytes in the ecological ditch were replaced by Myriophyllum aquaticum in 2014, which led to the increased average NO₃⁻-N and TN removal rates of 30.5% and 18.2%, respectively, Compared to in 2013. The vegetation of Myriophyllum aquaticum was beneficial to the improvement of N interception in ecological ditch. These findings clearly demonstrated that ecological ditch can substantially reduce N loss from surface runoff and be used as an important technique to prevent agricultural non-point N pollution.

Unification of the macro- and microbiome in trophic ecology

USDA-ARS?s Scientific Manuscript database

Biological control is a key part of virtually any IPM program, and microbial bio-control agents represent particularly effective agents because of their capacity to be applied via conventional spray application methods. We are showing that fungi function just as arthropods do in the food web—the fun...

ECOLOGICAL EFFECTS OF AEROSOL DRIFT FROM A SALTWATER COOLING SYSTEM

EPA Science Inventory

The local terrestrial effects of salt aerosol drift from powered spray modules and a mechanical draft cooling tower at Turkey Point, Florida were evaluated through field and controlled exposure studies. Indigenous vegetation, soil and fresh water were sampled over a year long per...

Evidence-based control of canine rabies: a critical review of population density reduction.

PubMed

Morters, Michelle K; Restif, Olivier; Hampson, Katie; Cleaveland, Sarah; Wood, James L N; Conlan, Andrew J K

2013-01-01

Control measures for canine rabies include vaccination and reducing population density through culling or sterilization. Despite the evidence that culling fails to control canine rabies, efforts to reduce canine population density continue in many parts of the world. The rationale for reducing population density is that rabies transmission is density-dependent, with disease incidence increasing directly with host density. This may be based, in part, on an incomplete interpretation of historical field data for wildlife, with important implications for disease control in dog populations. Here, we examine historical and more recent field data, in the context of host ecology and epidemic theory, to understand better the role of density in rabies transmission and the reasons why culling fails to control rabies. We conclude that the relationship between host density, disease incidence and other factors is complex and may differ between species. This highlights the difficulties of interpreting field data and the constraints of extrapolations between species, particularly in terms of control policies. We also propose that the complex interactions between dogs and people may render culling of free-roaming dogs ineffective irrespective of the relationship between host density and disease incidence. We conclude that vaccination is the most effective means to control rabies in all species. © 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society.

Drought offset ecological restoration program-induced increase in vegetation activity in the Beijing-Tianjin Sand Source Region, China.

PubMed

Wu, Zhitao; Wu, Jianjun; He, Bin; Liu, Jinghui; Wang, Qianfeng; Zhang, Hong; Liu, Yong

2014-10-21

To improve the ecological conditions, the Chinese government adopted six large-scale ecological restoration programs including 'Three-North Shelterbelt Project', "Grain for Green Project" and "Beijing-Tianjin Sand Source Control Project". Meanwhile, these ecologically vulnerable areas have experienced frequent droughts. However, little attention has been paid to the impact of drought on the effectiveness of these programs. Taking Beijing-Tianjin Sand Source Region (BTSSR) as study area, we investigated the role of droughts and ecological restoration program on trends of vegetation activities and to address the question of a possible "drought signal" in assessing effectiveness of ecological restoration program. The results demonstrate the following: (1) Vegetation activity increased in the BTSSR during 2000-2010, with 58.44% of the study area showing an increased NDVI, of which 11.80% had a significant increase at 0.95 confidential level. The decreasing NDVI trends were mainly concentrated in a southwest-to-northeast strip in the study area. (2) Drought was the main driving force for a decreasing trend of vegetation activity in the southwest-to-northeast regions of the BTSSR at the regional and spatial scales. Summer droughts in 2007 and 2009 contributed to the decreasing trend in NDVI. The severe and extreme droughts in summer reduced the NDVI by approximately 13.06% and 23.55%, respectively. (3) The residual analysis result showed that human activities, particularly the ecological restoration programs, have a positive impact on vegetation change. Hence, the decreasing trends in the southwest-to-northeast regions of the BTSSR cannot be explained by the improper ecological restoration program and is partly explained by droughts, especially summer droughts. Therefore, drought offset the ecological restoration program-induced increase in vegetation activity in the BTSSR.

Parasitic plants in agriculture: Chemical ecology of germination and host-plant location as targets for sustainable control: A review

Treesearch

Justin B. Runyon; John F. Tooker; Mark C. Mescher; Consuelo M. De Moraes

2009-01-01

Parasitic plants are among the most problematic pests of agricultural crops worldwide. Effective means of control are generally lacking, in part because of the close physiological connection between the established parasite and host plant hindering efficient control using traditional methods. Seed germination and host location are critical early-growth stages that...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, Brennan T; Jager, Yetta; March, Patrick

Reservoir releases are typically operated to maximize the efficiency of hydropower production and the value of hydropower produced. In practice, ecological considerations are limited to those required by law. We first describe reservoir optimization methods that include mandated constraints on environmental and other water uses. Next, we describe research to formulate and solve reservoir optimization problems involving both energy and environmental water needs as objectives. Evaluating ecological objectives is a challenge in these problems for several reasons. First, it is difficult to predict how biological populations will respond to flow release patterns. This problem can be circumvented by using ecologicalmore » models. Second, most optimization methods require complex ecological responses to flow to be quantified by a single metric, preferably a currency that can also represent hydropower benefits. Ecological valuation of instream flows can make optimization methods that require a single currency for the effects of flow on energy and river ecology possible. Third, holistic reservoir optimization problems are unlikely to be structured such that simple solution methods can be used, necessitating the use of flexible numerical methods. One strong advantage of optimal control is the ability to plan for the effects of climate change. We present ideas for developing holistic methods to the point where they can be used for real-time operation of reservoirs. We suggest that developing ecologically sound optimization tools should be a priority for hydropower in light of the increasing value placed on sustaining both the ecological and energy benefits of riverine ecosystems long into the future.« less

[Ecological vulnerability of coal mining area: a case study of Shengli Coalfield in Xilinguole of Inner Mongolia, China].

PubMed

Quan, Zhan-Jun; Li, Yuan; Li, Jun-Sheng; Han, Yu; Xiao, Neng-Wen; Fu, Meng-Di

2013-06-01

In this paper, an ecological vulnerability evaluation index system for the Shengli Coalfield in Xilinguole of Inner Mongolia was established, which included 16 factors in ecological sensitivity, natural and social pressure, and ecological recovery capacity, respectively. Based on the expert scoring method and analytic hierarchy process (AHP), an ecological vulnerability model was built for the calculation of the regional ecological vulnerability by means of RS and GIS spatial analysis. An analysis of the relationships between land use and ecological vulnerability was also made, and the results were tested by spatial auto-correlation analysis. Overall, the ecological vulnerability of the study area was at medium-high level. The exploitation of four opencast areas in the Coalfield caused a significant increase of ecological vulnerability. Moreover, due to the effects of mine drained water and human activities, the 300 -2000 m around the opencast areas was turning into higher ecologically fragile area. With further exploitation, the whole Coalfield was evolved into moderate and heavy ecological vulnerability area, and the coal resources mining was a key factor in this process. The cluster analysis showed that the spatial distribution of the ecological vulnerability in the study area had reasonable clustering characteristics. To decrease the population density, control the grazing capacity of grassland, and regulate the ratios of construction land and cultivated land could be the optimal ways for resolving the natural and social pressure, and to increase the investment and improve the vegetation recovery coefficient could be the fundamental measures for decreasing the ecological vulnerability of the study area.

Ecology of Anopheles darlingi Root with respect to vector importance: a review

PubMed Central

2011-01-01

Anopheles darlingi is one of the most important malaria vectors in the Americas. In this era of new tools and strategies for malaria and vector control it is essential to have knowledge on the ecology and behavior of vectors in order to evaluate appropriateness and impact of control measures. This paper aims to provide information on the importance, ecology and behavior of An. darlingi. It reviews publications that addressed ecological and behavioral aspects that are important to understand the role and importance of An. darlingi in the transmission of malaria throughout its area of distribution. The results show that Anopheles darlingi is especially important for malaria transmission in the Amazon region. Although numerous studies exist, many aspects determining the vectorial capacity of An. darlingi, i.e. its relation to seasons and environmental conditions, its gonotrophic cycle and longevity, and its feeding behavior and biting preferences, are still unknown. The vector shows a high degree of variability in behavioral traits. This makes it difficult to predict the impact of ongoing changes in the environment on the mosquito populations. Recent studies indicate a good ability of An. darlingi to adapt to environments modified by human development. This allows the vector to establish populations in areas where it previously did not exist or had been controlled to date. The behavioral variability of the vector, its adaptability, and our limited knowledge of these impede the establishment of effective control strategies. Increasing our knowledge of An. darlingi is necessary. PMID:21923902

In ecoregions across western USA streamflow increases during post-wildfire recovery

NASA Astrophysics Data System (ADS)

Wine, Michael L.; Cadol, Daniel; Makhnin, Oleg

2018-01-01

Continued growth of the human population on Earth will increase pressure on already stressed terrestrial water resources required for drinking water, agriculture, and industry. This stress demands improved understanding of critical controls on water resource availability, particularly in water-limited regions. Mechanistic predictions of future water resource availability are needed because non-stationary conditions exist in the form of changing climatic conditions, land management paradigms, and ecological disturbance regimes. While historically ecological disturbances have been small and could be neglected relative to climatic effects, evidence is accumulating that ecological disturbances, particularly wildfire, can increase regional water availability. However, wildfire hydrologic impacts are typically estimated locally and at small spatial scales, via disparate measurement methods and analysis techniques, and outside the context of climate change projections. Consequently, the relative importance of climate change driven versus wildfire driven impacts on streamflow remains unknown across the western USA. Here we show that considering wildfire in modeling streamflow significantly improves model predictions. Mixed effects modeling attributed 2%-14% of long-term annual streamflow to wildfire effects. The importance of this wildfire-linked streamflow relative to predicted climate change-induced streamflow reductions ranged from 20%-370% of the streamflow decrease predicted to occur by 2050. The rate of post-wildfire vegetation recovery and the proportion of watershed area burned controlled the wildfire effect. Our results demonstrate that in large areas of the western USA affected by wildfire, regional predictions of future water availability are subject to greater structural uncertainty than previously thought. These results suggest that future streamflows may be underestimated in areas affected by increased prevalence of hydrologically relevant ecological disturbances such as wildfire.

[Dynamic evaluation on landscape connectivity of ecological land: a case study of Shenzhen, Guangdong Province of South China].

PubMed

Wu, Jian-Sheng; Liu, Hong-Meng; Huang, Xiu-Lan; Feng, Zhe

2012-09-01

Ecological land is the most crucial and sensitive land use type in rapidly urbanizing areas. Landscape connectivity can help us to better understand the interactions between landscape structure and landscape function. By using the land use data of Shenzhen from 1996 to 2008 and the graph theory- based integral index of connectivity (IIC), probability index of connectivity (PC), and importance value of patches (dPC), a dynamic evaluation on the landscape connectivity of ecological land in the City was conducted, and a spatial assessment was made to identify the most important patches for maintaining overall landscape connectivity. In combining with the basic ecological controlling line in Shenzhen, the variations of the landscape connectivity of the ecological land inside and outside the basic ecological controlling line were evaluated. From 1996 to 2008, the overall landscape connectivity of the ecological land in Shenzhen displayed a downward trend, the importance and the spatial distribution of the important patches for maintaining the overall landscape connectivity changed, and the basic ecological controlling line played definite roles in maintaining the landscape connectivity of ecological land inside the line.

Limitations of a metabolic network-based reverse ecology method for inferring host-pathogen interactions.

PubMed

Takemoto, Kazuhiro; Aie, Kazuki

2017-05-25

Host-pathogen interactions are important in a wide range of research fields. Given the importance of metabolic crosstalk between hosts and pathogens, a metabolic network-based reverse ecology method was proposed to infer these interactions. However, the validity of this method remains unclear because of the various explanations presented and the influence of potentially confounding factors that have thus far been neglected. We re-evaluated the importance of the reverse ecology method for evaluating host-pathogen interactions while statistically controlling for confounding effects using oxygen requirement, genome, metabolic network, and phylogeny data. Our data analyses showed that host-pathogen interactions were more strongly influenced by genome size, primary network parameters (e.g., number of edges), oxygen requirement, and phylogeny than the reserve ecology-based measures. These results indicate the limitations of the reverse ecology method; however, they do not discount the importance of adopting reverse ecology approaches altogether. Rather, we highlight the need for developing more suitable methods for inferring host-pathogen interactions and conducting more careful examinations of the relationships between metabolic networks and host-pathogen interactions.

A perspective on CELSS control issues

NASA Technical Reports Server (NTRS)

Blackwell, Ann L.

1990-01-01

Some issues of Closed Ecological Life Support System (CELSS) analysis and design are effectively addressed from a systems control perspective. CELSS system properties that may be elucidated using control theory in conjunction with mathematical and simulation modeling are enumerated. The approach that is being taken to the design of a control strategy for the Crop Growth Research Chamber (CGRC) and the relationship of that approach to CELSS plant growth unit subsystems control is described.

The development and effectiveness of an ecological momentary intervention to increase daily fruit and vegetable consumption in low-consuming young adults.

PubMed

Brookie, Kate L; Mainvil, Louise A; Carr, Anitra C; Vissers, Margreet C M; Conner, Tamlin S

2017-01-01

To develop and test the effectiveness of a mobile-phone based ecological momentary intervention (EMI) to increase fruit and vegetable (FV) consumption in low-consuming young adults. A two-week randomised controlled trial of low-FV consuming young adults ages 18-25 years (n = 171) compared three conditions: ecological momentary intervention (EMI), fruit and vegetable intervention (FVI), and a diet-as-usual control (ANZCTRN12615000183583). Participants in the EMI condition were sent two targeted text messages a day for 13 days and were asked to increase daily FV consumption to at least five servings. These messages were designed, using the Health Action Process Approach, to address salient beliefs identified as effective in a preliminary focus group investigation. Participants in the FVI condition were provided two servings of FV a day (carrots, kiwifruit or oranges, and apples) to eat in addition to their current diet. Control participants ate their normal diet. Participants reported their daily servings of FV each evening during the study using a smartphone-delivered survey. Blood samples testing plasma vitamin C and total carotenoids were taken pre- and post-intervention as an objective biomarker of FV intake. Participants in the EMI and FVI conditions reported higher daily servings of FV - approximately +1 serving per day more compared to control (EMI = 3.7 servings/day; FVI = 3.7 servings/day; Control = 2.8 servings/day) and approximately +1.2 servings compared to baseline. Increases in objective biomarkers for the experimental conditions supported the validity of self-reported FV consumption. Our results provide initial proof of concept that EMI strategies (with minor financial assistance) are as effective as giving FV in increasing FV consumption in educated, low-consuming young adults. Copyright © 2016 Elsevier Ltd. All rights reserved.

Echinococcosis: Control and Prevention.

PubMed

Craig, P S; Hegglin, D; Lightowlers, M W; Torgerson, P R; Wang, Q

2017-01-01

Human cystic echinococcosis (CE) has been eliminated or significantly reduced as a public health problem in several previously highly endemic regions. This has been achieved by the long-term application of prevention and control measures primarily targeted to deworming dogs, health education, meat inspection, and effective surveillance in livestock and human populations. Human CE, however, remains a serious neglected zoonotic disease in many resource-poor pastoral regions. The incidence of human alveolar echinococcosis (AE) has increased in continental Europe and is a major public health problem in parts of Eurasia. Better understanding of wildlife ecology for fox and small mammal hosts has enabled targeted anthelmintic baiting of fox populations and development of spatially explicit models to predict population dynamics for key intermediate host species and human AE risk in endemic landscapes. Challenges that remain for echinococcosis control include effective intervention in resource-poor communities, better availability of surveillance tools, optimal application of livestock vaccination, and management and ecology of dog and wildlife host populations. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ecological regulation of black leaf streak disease driven by plant richness in banana agroecosystems.

PubMed

Poeydebat, Charlotte; Carval, Dominique; Tixier, Philippe; Daribo, Marie-Odette; De Lapeyre De Bellaire, Luc

2018-05-04

Black leaf streak disease (BLSD), caused by the fungus Mycosphaerella fijiensis, is an important threat to banana production. Although its control relies on costly and unsustainable use of fungicides, ecological regulation of BLSD linked to field-scale plant diversity has received little attention. We monitored banana phytometers in plots in banana-based fields where no fungicides were applied. Within each plot, we measured plant richness in three strata, canopy openness, necrotic leaf removal, Musa abundance and richness. We quantified ecological regulation of five BLSD parameters (inoculum sources, spore abundance, lesion density, incubation time, and the area under the disease progression curve) and identified, using structural equation modeling, the characteristics of the plant community and the mechanisms likely responsible for the regulation. Regulation occurred, but most effectively before lesion formation, and was mainly related to plant richness between 1.5 and 5m high. A barrier effect, rather than a dilution effect, more likely limited spore abundance. Our results support the hypothesis that the potential effects of plant richness on leaf-scale microclimate variability and on the diversity of epiphyllic microorganisms are involved in the regulation of incubation time and lesion density. Field-scale management of plant diversity may be a promising lever to foster ecological regulation of BLSD.

40 CFR 272.201 - Arkansas State-administered program: Final authorization.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) Arkansas Pollution Control and Ecology (APC&E) Commission Regulation No. 23, Hazardous Waste Management, as... Three, Sections 19 and 21, 22; Chapter Five, Section 28. (x) Arkansas Pollution Control and Ecology (APC... Ecology (APC&E) Commission, Regulation No. 8, Administrative Procedures, June 12, 2000. (3) The following...

40 CFR 272.201 - Arkansas State-administered program: Final authorization.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) Arkansas Pollution Control and Ecology (APC&E) Commission Regulation No. 23, Hazardous Waste Management, as... Three, Sections 19 and 21, 22; Chapter Five, Section 28. (x) Arkansas Pollution Control and Ecology (APC... Ecology (APC&E) Commission, Regulation No. 8, Administrative Procedures, June 12, 2000. (3) The following...

40 CFR 272.201 - Arkansas State-administered program: Final authorization.

Code of Federal Regulations, 2014 CFR

2014-07-01

...) Arkansas Pollution Control and Ecology (APC&E) Commission Regulation No. 23, Hazardous Waste Management, as... Three, Sections 19 and 21, 22; Chapter Five, Section 28. (x) Arkansas Pollution Control and Ecology (APC... Ecology (APC&E) Commission, Regulation No. 8, Administrative Procedures, June 12, 2000. (3) The following...

40 CFR 272.201 - Arkansas State-administered program: Final authorization.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) Arkansas Pollution Control and Ecology (APC&E) Commission Regulation No. 23, Hazardous Waste Management, as... Three, Sections 19 and 21, 22; Chapter Five, Section 28. (x) Arkansas Pollution Control and Ecology (APC... Ecology (APC&E) Commission, Regulation No. 8, Administrative Procedures, June 12, 2000. (3) The following...

Studies of the Ecological Impact of Repetitive Aerial Applications of Herbicides on the Ecosystem of Test Area C-52A, Eglin AFB, Florida

DTIC Science & Technology

1975-08-01

mosquito Beuthss. Microbiology . Effluents. control was rettlizcd using niosquito fish Identifiers: ’Water pollution effects(Arsimals)- Identifiers...support differences between the control and tesi , animals. It is interesting to note the magnitude of the standard deviations between spleen weights from

Funding needed for assessments of weed biological control

Treesearch

John L. Maron; Dean E. Pearson; Stephen M. Hovick; Walter P. Carson

2010-01-01

Invasive non-native plants are a serious economic and ecological problem worldwide, and major efforts are therefore devoted to reducing weed abundance in agricultural and natural settings. Effective options for reducing invasive abundance and spread are few, although one common approach is biological control - the introduction of specialist herbivores or pathogens from...

Biodiversity and ecosystem risks arising from using guppies to control mosquitoes

Treesearch

Rana W. El-Sabaawi; Therese C. Frauendorf; Piata S. Marques; Richard A. Mackenzie; Luisa R. Manna; Rosana Mazzoni; Dawn A. T. Phillip; Misha L. Warbanski; Eugenia Zandon

2016-01-01

Deploying mosquito predators such as the guppy (Poecilia reticulata) into bodies of water where mosquitoes breed is a common strategy for limiting the spread of disease-carrying mosquitoes. Here, we draw on studies from epidemiology, conservation, ecology and evolution to show that the evidence for the effectiveness of guppies in controlling...

Ecological restoration success is higher for natural regeneration than for active restoration in tropical forests

PubMed Central

Crouzeilles, Renato; Ferreira, Mariana S.; Chazdon, Robin L.; Lindenmayer, David B.; Sansevero, Jerônimo B. B.; Monteiro, Lara; Iribarrem, Alvaro; Latawiec, Agnieszka E.; Strassburg, Bernardo B. N.

2017-01-01

Is active restoration the best approach to achieve ecological restoration success (the return to a reference condition, that is, old-growth forest) when compared to natural regeneration in tropical forests? Our meta-analysis of 133 studies demonstrated that natural regeneration surpasses active restoration in achieving tropical forest restoration success for all three biodiversity groups (plants, birds, and invertebrates) and five measures of vegetation structure (cover, density, litter, biomass, and height) tested. Restoration success for biodiversity and vegetation structure was 34 to 56% and 19 to 56% higher in natural regeneration than in active restoration systems, respectively, after controlling for key biotic and abiotic factors (forest cover, precipitation, time elapsed since restoration started, and past disturbance). Biodiversity responses were based primarily on ecological metrics of abundance and species richness (74%), both of which take far less time to achieve restoration success than similarity and composition. This finding challenges the widely held notion that natural forest regeneration has limited conservation value and that active restoration should be the default ecological restoration strategy. The proposition that active restoration achieves greater restoration success than natural regeneration may have arisen because previous comparisons lacked controls for biotic and abiotic factors; we also did not find any difference between active restoration and natural regeneration outcomes for vegetation structure when we did not control for these factors. Future policy priorities should align the identified patterns of biophysical and ecological conditions where each or both restoration approaches are more successful, cost-effective, and compatible with socioeconomic incentives for tropical forest restoration. PMID:29134195

Ecological restoration success is higher for natural regeneration than for active restoration in tropical forests.

PubMed

Crouzeilles, Renato; Ferreira, Mariana S; Chazdon, Robin L; Lindenmayer, David B; Sansevero, Jerônimo B B; Monteiro, Lara; Iribarrem, Alvaro; Latawiec, Agnieszka E; Strassburg, Bernardo B N

2017-11-01

Is active restoration the best approach to achieve ecological restoration success (the return to a reference condition, that is, old-growth forest) when compared to natural regeneration in tropical forests? Our meta-analysis of 133 studies demonstrated that natural regeneration surpasses active restoration in achieving tropical forest restoration success for all three biodiversity groups (plants, birds, and invertebrates) and five measures of vegetation structure (cover, density, litter, biomass, and height) tested. Restoration success for biodiversity and vegetation structure was 34 to 56% and 19 to 56% higher in natural regeneration than in active restoration systems, respectively, after controlling for key biotic and abiotic factors (forest cover, precipitation, time elapsed since restoration started, and past disturbance). Biodiversity responses were based primarily on ecological metrics of abundance and species richness (74%), both of which take far less time to achieve restoration success than similarity and composition. This finding challenges the widely held notion that natural forest regeneration has limited conservation value and that active restoration should be the default ecological restoration strategy. The proposition that active restoration achieves greater restoration success than natural regeneration may have arisen because previous comparisons lacked controls for biotic and abiotic factors; we also did not find any difference between active restoration and natural regeneration outcomes for vegetation structure when we did not control for these factors. Future policy priorities should align the identified patterns of biophysical and ecological conditions where each or both restoration approaches are more successful, cost-effective, and compatible with socioeconomic incentives for tropical forest restoration.

[Ecological executive function characteristics and effects of executive function on social adaptive function in school-aged children with epilepsy].

PubMed

Xu, X J; Wang, L L; Zhou, N

2016-02-23

To explore the characteristics of ecological executive function in school-aged children with idiopathic or probably symptomatic epilepsy and examine the effects of executive function on social adaptive function. A total of 51 school-aged children with idiopathic or probably symptomatic epilepsy aged 5-12 years at our hospital and 37 normal ones of the same gender, age and educational level were included. The differences in ecological executive function and social adaptive function were compared between the two groups with the Behavior Rating Inventory of Executive Function (BRIEF) and Child Adaptive Behavior Scale, the Pearson's correlation test and multiple stepwise linear regression were used to explore the impact of executive function on social adaptive function. The scores of school-aged children with idiopathic or probably symptomatic epilepsy in global executive composite (GEC), behavioral regulation index (BRI) and metacognition index (MI) of BRIEF ((62±12), (58±13) and (63±12), respectively) were significantly higher than those of the control group ((47±7), (44±6) and (48±8), respectively))(P<0.01). The scores of school-aged children with idiopathic or probably symptomatic epilepsy in adaptive behavior quotient (ADQ), independence, cognition, self-control ((86±22), (32±17), (49±14), (41±16), respectively) were significantly lower than those of the control group ((120±12), (59±14), (59±7) and (68±10), respectively))(P<0.01). Pearson's correlation test showed that the scores of BRIEF, such as GEC, BRI, MI, inhibition, emotional control, monitoring, initiation and working memory had significantly negative correlations with the score of ADQ, independence, self-control ((r=-0.313--0.741, P<0.05)). Also, GEC, inhibition, MI, initiation, working memory, plan, organization and monitoring had significantly negative correlations with the score of cognition ((r=-0.335--0.437, P<0.05)); Multiple stepwise linear regression analysis showed that BRI, inhibition and working memory were closely related with the social adaptive function of school-aged children with idiopathic or probably symptomatic epilepsy. School-aged children with idiopathic or probably symptomatic epilepsy may have significantly ecological executive function impairment and social adaptive function reduction. The aspects of BRI, inhibition and working memory in ecological executive function are significantly related with social adaptive function in school-aged children with epilepsy.

Quantifying the ecological success of a community-based wildlife conservation area in Tanzania

PubMed Central

Lee, Derek E

2018-01-01

Abstract In Tanzania, community-based natural resource management of wildlife occurs through the creation of Wildlife Management Areas (WMAs). WMAs consist of multiple villages designating land for wildlife conservation, and sharing a portion of subsequent tourism revenues. Nineteen WMAs are currently operating, encompassing 7% of Tanzania’s land area, with 19 more WMAs planned. The ecological success or failure of WMAs for wildlife conservation has yet to be quantified. We defined ecological success in this case as significantly greater densities of wildlife and significantly lower densities of livestock in the WMA relative to the control site, after the WMA was established. We used 4 years of distance sampling surveys conducted 6 times per year for wild and domestic ungulates to quantify wildlife and livestock densities before and after the establishment and implementation of management efforts at Randilen WMA, relative to a control site on adjacent land of similar vegetation and habitat types. We documented similarity between the sites before WMA establishment, when both sites were managed by the same authority. After WMA establishment, we documented significantly higher densities of resident wildlife (giraffes and dik-diks) and lower densities of cattle in the WMA, relative to the control site, indicating short-term ecological success. Continued monitoring is necessary to determine longer-term effects, and to evaluate management decisions. PMID:29867255

Geomorphological and ecological effects of check dams in mountain torrents of Southern Italy

NASA Astrophysics Data System (ADS)

Zema, Demetrio Antonio; Bombino, Giuseppe; Denisi, Pietro; Tamburino, Vincenzo; Marcello Zimbone, Santo

2017-04-01

It is known that installation of check dams noticeably influences torrent morphology and ecology. However, the effects of check dams on channel section and riparian vegetation of torrents are not yet completely understood. This paper provides a further contribution to a better comprehension of the actions played by check dams on hydrological and geomorphological processes in headwaters and their effects on riparian ecosystem. Field surveys on channel morphology, bed material and riparian vegetation were carried out close to five check dams in each of four mountain reaches of Calabria (Southern Italy). For each check dam three transects (one upstream, one downstream and one far from the check dam, located in the undisturbed zone and adopted as control) were identified; at each transect, a set of geomorphological and ecological indicators were surveyed as follows. Channel section morphology was assessed by the width/depth ratio (w/d); the median particle size (D50) and the finer sediment fraction (%fines) were chosen to characterize channel bed material; the specific discharge (q, the discharge per channel unit width) was assumed as measure of the flow regime. Vegetation cover and structure were evaluated by Global Canopy Cover (GCC) and Weighted Canopy Height (WCH) respectively (Bombino et al., 2008); the index of alpha-diversity (H-alpha, Hill, 1973) and the ratio between the number of alien species and the number of native species (NSA/NSN) were chosen as indicators of species richness/abundance and degree of vegetation integrity, respectively. Compared to the control transects, the values of w/d were higher upstream of check dams and lower downstream; conversely, q was lower upstream and higher in downstream sites. Upstream of the check dams D50 of bed material was lower and %fines was higher compared to the control transects; vice versa, the downstream transects showed higher D50 and lower %fines. The differences in the riparian vegetation among transects were found as the torrent ecological response to the strong contrasts surveyed in hydrological (q) and geomorphological (w/d, D50 and %fines) characteristics. Compared to control transects, vegetation was more extensive (higher GCC) and developed (higher WCH) in the upstream zones; the reverse pattern was noticed in the downstream transects (lower GCC and WCH). The indexes H-alpha and NSA/NSN were higher upstream of check dams: the presence of the check dams induced higher species richness and evenness, with alien species prevailing over native ones in the sedimentation wedge. Conversely, downstream of check dams H-alpha and NSA/NSN were lower: here, riparian vegetation lost some herbaceous species and assumed a terrestrial character. Overall, this study confirms on a quantitative approach that check dams have far reaching effects on geomorphology and ecology of mountain torrent channels; as a consequence, important and complex changes occur not only in the extent and development of riparian vegetation, but also in the species diversity and distribution. REFERENCES - Bombino G., Gurnell A.M., Tamburino V., Zema D.A., Zimbone S.M. 2008. Sediment size variation in torrents with check-dams: effects on riparian vegetation. Ecological Engineering 32(2), 166-177. - Hill MO. 1973. Diversity and evenness: a unifying notation and its consequences. Ecology 54: 427-431.

Seasonal Differences in Climatic Controls of Vegetation Growth in the Beijing-Tianjin Sand Source Region of China.

NASA Astrophysics Data System (ADS)

Wang, H.

2017-12-01

Seasonal differences in climatic controls of vegetation growth in the Beijing-Tianjin Sand Source Region of China Bin He1 , Haiyan Wan11 State Key Laboratory of Earth Surface Processes and Resource Ecology, College of Global Change and Earth System Science, Beijing Normal University, Beijing 100875, China Corresponding author: Bin He, email addresses: hebin@bnu.edu.cnPhone:+861058806506, Address: Beijing Normal University, College of Global Change and Earth System Science, Beijing Normal University, Beijing 100875, China. Email addresses of co-authors: wanghaiyan@mail.bnu.edu.cnABSTRACTLaunched in 2000, the Beiing-Tainjin Sand Source Controlling Project (BTSSCP) is an ecological restoration project intended to prevent desertification in China. Evidence from multiple sources has confirmed increases in vegetation growth in the BTSSCP region since the initiation of the project. Precipitation and related soil moisture conditions typically are considered to be the main drivers of vegetation growth in this arid region. However, by investigating the relationships between vegetation growth and corresponding climatic factors, we identified seasonal variation in the climatic constraints of vegetation growth. In spring, vegetation growth is stimulated mainly by elevated temperature, whereas precipitation is the lead driver of summer greening. In autumn, positive effects of both temperature and precipitation on vegetation growth were observed. Furthermore, strong biosphere-atmosphere interactions were observed in this region. Spring warming promotes vegetation growth, but also reduces soil moisture. Summer greening has a strong cooling effect on land surface temperature. These results indicate that 1) precipitation-based projections of vegetation growth may be misleading; and 2) the ecological and environment consequences of ecological projects should be comprehensively evaluated. KEYWORDS: vegetation growth, climatic drivers, seasonal variation, BTSSCP

The behavior of multiple independent managers and ecological traits interact to determine prevalence of weeds.

PubMed

Coutts, Shaun R; Yokomizo, Hiroyuki; Buckley, Yvonne M

2013-04-01

Management of damaging invasive plants is often undertaken by multiple decision makers, each managing only a small part of the invader's population. As weeds can move between properties and re-infest eradicated sites from unmanaged sources, the dynamics of multiple decision makers plays a significant role in weed prevalence and invasion risk at the landscape scale. We used a spatially explicit agent-based simulation to determine how individual agent behavior, in concert with weed population ecology, determined weed prevalence. We compared two invasive grass species that differ in ecology, control methods, and costs: Nassella trichotoma (serrated tussock) and Eragrostis curvula (African love grass). The way decision makers reacted to the benefit of management had a large effect on the extent of a weed. If benefits of weed control outweighed the costs, and either net benefit was very large or all agents were very sensitive to net benefits, then agents tended to act synchronously, reducing the pool of infested agents available to spread the weed. As N. trichotoma was more damaging than E. curvula and had more effective control methods, agents chose to manage it more often, which resulted in lower prevalence of N. trichotoma. A relatively low number of agents who were intrinsically less motivated to control weeds led to increased prevalence of both species. This was particularly apparent when long-distance dispersal meant each infested agent increased the invasion risk for a large portion of the landscape. In this case, a small proportion of land mangers reluctant to control, regardless of costs and benefits, could lead to the whole landscape being infested, even when local control stopped new infestations. Social pressure was important, but only if it was independent of weed prevalence, suggesting that early access to information, and incentives to act on that information, may be crucial in stopping a weed from infesting large areas. The response of our model to both behavioral and ecological parameters was highly nonlinear. This implies that the outcomes of weed management programs that deal with multiple land mangers could be highly variable in both space and through time.

The effect of educational intervention based on an Ecological-social model on consuming fruit and vegetables in women in Ilam.

PubMed

Shafiei, Leili; Taymoori, Parvaneh; Maleki, Afshin; Sayehmiri, Kourosh

2017-12-01

The effect of instructional models on the changing behavior of consuming fruit and vegetables in the prevention of diseases caused by consumption of foods including rice, contaminated with toxic metals, has not been investigated in Iran yet. To compare an Ecological-social model (ECO) group and Control group in increasing fruit and vegetable consumption. This research involved implementation of a six-month randomized controlled educational interventionist program into a group of Ecological-social framework along with a control group, totally summing up to 160 women between 18 and 50 years of age in Ilam, Iran in 2014. The questionnaire included knowledge, social support construct (immediate family, relatives, friends, colleagues and neighbors.) and fruit and vegetable intake in both groups before and after the intervention was examined. Data were analyzed by SPSS version 16 using the signed ranks test, and repeated measures analysis of variance analysis, and confidence interval of 95% were employed. The results of the signed ranks test showed a significant increase in social support in the intervention group (p<0.001). This test showed a significant increase in fruit and vegetable consumption and a significant increase in the number of women using healthy rice (p<0.001), and a significant reduction in the number of women consuming unhealthy rice in the intervention group (p<0.001), that determines dietary intake improvement after the intervention compared with before the intervention (p<0.01). However, this improvement was not observed in the control group. The results showed that ECO plays an effective role in improving fruit and vegetable consumption in women. Therefore, this model was implemented as a health protocol through health-care centers to conduct the prevention of complications resulting from the use of food contaminated with toxic metals.

The short-term effects of a routine poisoning campaign on the movements and detectability of a social top-predator.

PubMed

Allen, Benjamin L; Engeman, Richard M; Leung, Luke K-P

2014-02-01

Top-predators can be important components of resilient ecosystems, but they are still controlled in many places to mitigate a variety of economic, environmental and/or social impacts. Lethal control is often achieved through the broad-scale application of poisoned baits. Understanding the direct and indirect effects of such lethal control on subsequent movements and behaviour of survivors is an important pre-requisite for interpreting the efficacy and ecological outcomes of top-predator control. In this study, we use GPS tracking collars to investigate the fine-scale and short-term movements of dingoes (Canis lupus dingo and other wild dogs) in response to a routine poison-baiting program as an example of how a common, social top-predator can respond (behaviourally) to moderate levels of population reduction. We found no consistent control-induced differences in home range size or location, daily distance travelled, speed of travel, temporal activity patterns or road/trail usage for the seven surviving dingoes we monitored immediately before and after a typical lethal control event. These data suggest that the spatial behaviour of surviving dingoes was not altered in ways likely to affect their detectability, and if control-induced changes in dingoes' ecological function did occur, these may not be related to altered spatial behaviour or movement patterns.

Preliminary results on the control of Aedes spp. in a remote Guatemalan community vulnerable to dengue, chikungunya and Zika virus: community participation and use of low-cost ecological ovillantas for mosquito control

PubMed Central

Ulibarri, Gerard; Betanzos, Angel; Betanzos, Mireya; Rojas, Juan Jacobo

2017-01-01

Objective: To study the effectiveness of an integrated intervention of health worker training, a low-cost ecological mosquito ovitrap, and community engagement on Aedes spp. mosquito control over 10 months in 2015 in an urban remote community in Guatemala at risk of dengue, chikungunya and Zika virus transmission. Methods: We implemented a three-component integrated intervention consisting of: web-based training of local health personnel in vector control, cluster-randomized assignment of an ecological modified ovitrap (ovillantas: ovi=egg, llanta=tire) or standard ovitraps to capture Aedes spp. mosquito eggs (no efforts have been taken to determine the exact Aedes species at this moment), and community engagement to promote participation of community members and health personnel in the understanding and maintenance of ovitraps for mosquito control. The intervention was implemented in local collaboration with Guatemala’s  Ministry of Health’s Vector Control Programme, and in international collaboration with the National Institute of Public Health in Mexico. Findings: Eighty percent of the 25 local health personnel enrolled in the training programme received accreditation of their improved knowledge of vector control. When ovillantas were used in a cluster of ovitraps (several in proximity), significantly more eggs were trapped by  ecological ovillantas than standard ovitraps over the 10 month (42 week) study period (t=5.2577; p<0.05). Repetitive filtering and recycling of the attractant solution (or water) kept the ovillanta clean, free from algae growth. Among both community members and health workers, the levels of knowledge, interest, and participation in community mosquito control and trapping increased. Recommendations for enhancing and sustaining community mosquito control were identified. Conclusion: Our three-component integrated intervention proved beneficial to this remote community at risk of mosquito-borne diseases such as dengue, chikungunya, and Zika. The combination of training of health workers, cluster use of low-cost ecological ovillanta to destroy the second generation of mosquitoes, and community engagement ensured the project met local needs and fostered collaboration and participation of the community, which can help improve sustainability. The ovillanta intervention and methodology may be modified to target other species such as Culex, should it be established that such mosquitoes carry Zika virus in addition to Aedes. PMID:28105304

The persistence and ecological impacts of a cyanobacterium genetically engineered to express mosquitocidal Bacillus thuringiensis toxins.

PubMed

Ketseoglou, Irene; Bouwer, Gustav

2016-05-10

The cyanobacterium Anabaena PCC 7120#11 has been genetically engineered to act as a delivery vehicle for Bacillus thuringiensis subspecies israelensis mosquitocidal toxins. To address ecological concerns about releasing this genetically engineered microorganism into the environment for mosquito larva control, the persistence and ecological impacts of PCC 7120#11 was evaluated using multi-species, standardized aquatic microcosms. The microcosms were set up as described in ASTM E1366-02 (Standard Practice for Standardized Aquatic Microcosms: Fresh Water), with a few modifications. The treatment group microcosms were inoculated with PCC 7120#11 and key water quality parameters and non-target effects were compared between the treatment and control groups over a period of 35 days. PCC 7120#11 decreased from a concentration of 4.50 × 10(6) cells/ml (at inoculation) to 1.32 × 10(3) cells/ml after 4 weeks and larvicidal activity against third instar larvae of Anopheles arabiensis was only evident for two weeks after treatment. Both treatment and the interaction of treatment and time had a significant effect on nitrate, phosphate and photosynthetic microorganism concentrations. Treatment with PCC 7120#11 caused a temporary spike in ammonia in the microcosms a week after treatment, but the concentrations were well below acute and chronic criteria values for ammonia in freshwater ecosystems. Cyprinotus vidua concentrations were not significantly different between PCC 7120#11 and control microcosms. In PCC 7120#11 microcosms, Daphnia pulex concentrations were significantly lower than control concentrations between days 18 and 25. By the end of the experiment, none of the measured variables were significantly different between the treatment groups. The standard aquatic microcosm experiments provided more data on the ecological impacts of PCC 7120#11 than single-organism assessments would have. On the basis of the relatively minor, short-term effects that PCC 7120#11 had on water quality parameters and non-target invertebrates, further evaluation of PCC 7120#11 for use in integrated vector management is warranted.

Understanding microbiomes for plant disease control

USDA-ARS?s Scientific Manuscript database

A rigorous understanding of the microbiomes associated with plants holds tremendous potential for suggesting new management targets that will more effectively manage pathogens and improve plant performance. Characterizing ecological interactions among microbial species within the phytobiome is essen...

Oxygen, ecology, and the Cambrian radiation of animals

NASA Astrophysics Data System (ADS)

Sperling, Erik A.; Frieder, Christina A.; Raman, Akkur V.; Girguis, Peter R.; Levin, Lisa A.; Knoll, Andrew H.

2013-08-01

The Proterozoic-Cambrian transition records the appearance of essentially all animal body plans (phyla), yet to date no single hypothesis adequately explains both the timing of the event and the evident increase in diversity and disparity. Ecological triggers focused on escalatory predator-prey "arms races" can explain the evolutionary pattern but not its timing, whereas environmental triggers, particularly ocean/atmosphere oxygenation, do the reverse. Using modern oxygen minimum zones as an analog for Proterozoic oceans, we explore the effect of low oxygen levels on the feeding ecology of polychaetes, the dominant macrofaunal animals in deep-sea sediments. Here we show that low oxygen is clearly linked to low proportions of carnivores in a community and low diversity of carnivorous taxa, whereas higher oxygen levels support more complex food webs. The recognition of a physiological control on carnivory therefore links environmental triggers and ecological drivers, providing an integrated explanation for both the pattern and timing of Cambrian animal radiation.

Antimicrobial Active Clothes Display No Adverse Effects on the Ecological Balance of the Healthy Human Skin Microflora

PubMed Central

Hoefer, Dirk; Hammer, Timo R.

2011-01-01

The progressive public use of antimicrobial clothes has raised issues concerning skin health. A placebo-controlled side-to-side study was run with antimicrobial clothes versus fabrics of similar structure but minus the antimicrobial activity, to evaluate possible adverse effects on the healthy skin microflora. Sixty volunteers were enrolled. Each participant received a set of form-fitting T-shirts constructed in 2 halves: an antibacterial half, displaying activities of 3–5 log-step reductions due to silver-finishes or silver-loaded fibres and a nonantibacterial control side. The microflora of the scapular skin was analyzed weekly for opportunistic and pathogenic microorganisms over six weeks. The antibacterial halves did not disturb the microflora in number or composition, whereas a silver-containing deodorant displayed a short-term disturbance. Furthermore, parameters of skin morphology and function (TEWL, pH, moisture) did not show any significant shifts. In summary, antimicrobial clothes did not show adverse effects on the ecological balance of the healthy skin microflora. PMID:22363849

Effects of light pollution on the emergent fauna of shallow marine ecosystems: Amphipods as a case study.

PubMed

Navarro-Barranco, Carlos; Hughes, Lauren Elizabeth

2015-05-15

Light pollution from coastal urban development is a widespread and increasing threat to biodiversity. Many amphipod species migrate between the benthos and the pelagic environment and light seems is a main ecological factor which regulates migration. We explore the effect of artificial lighting on amphipod assemblages using two kind of lights, LED and halogen, and control traps in shallow waters of the Great Barrier Reef. Both types of artificial light traps showed a significantly higher abundance of individuals for all species in comparison to control traps. LED lights showed a stronger effect over the amphipod assemblages, with these traps collecting a higher number of individuals and differing species composition, with some species showing a specific attraction to LED light. As emergent amphipods are a key ecological group in the shallow water environment, the impact of artificial light can affect the broader functioning of the ecosystem. Copyright © 2015 Elsevier Ltd. All rights reserved.

Protective effect of breastfeeding: an ecologic study of Haemophilus influenzae meningitis and breastfeeding in a Swedish population.

PubMed

Silfverdal, S A; Bodin, L; Olcén, P

1999-02-01

In Orebro County, Sweden, a 2.5-fold increase in the incidence of Haemophilus influenzae (HI) meningitis was found between 1970 and 1980. In a case-control study of possible risk factors for invasive HI infection conducted in the same area, 1987-1992, breastfeeding was found to be a strong protective factor. In order to study the relation between incidence rates of HI meningitis between 1956-1992 and breastfeeding rates in the population an ecologic study was performed. A strong (negative) correlation between breastfeeding and incidence of HI infection 5 to 10 years later (rho(xy) (s) approximately -0.6) was seen, whereas no relation seems to exist for the time lag 15 years and beyond. The correlation for contemporary data was intermediate. There were similar results for the breastfeeding proportions at 2, 4 as well as 6 months of age. Our ecologic data are consistent with results from our case-control study. The time-lag for the delayed effect on the population level could be estimated although sparse data make the estimates vulnerable to sampling fluctuations. Limitations with ecologic studies are discussed. There seems to be an association between high breastfeeding rate in the population and a reduced incidence of HI meningitis 5 to 10 years later. These results do have implications on strategies for breastfeeding promotion, especially in countries where Hib vaccination is too costly and not yet implemented.

The issues of weed infestation with environmentally hazardous plants and methods of their control

NASA Astrophysics Data System (ADS)

Bogdanov, V. L.; Posternak, T. S.; Pasko, O. A.; Kovyazin, V. F.

2016-09-01

The authors analyze expansion of segetal and ruderal vegetation on agricultural lands in Leningrad and Tomsk oblasts, typical for the European and Asian parts of Russia. The spreading conditions, composition of species, biological features and ecological requirements of the most aggressive species are identified. Some effective ways of weed control are suggested.

Development of a zoning-based environmental-ecological-coupled model for lakes to assess lake restoration effect

NASA Astrophysics Data System (ADS)

Xu, Mengjia; Zou, Changxin; Zhao, Yanwei

2017-04-01

Environmental/ecological models are widely used for lake management as they provide a means to understand physical, chemical and biological processes in highly complex ecosystems. Most research focused on the development of environmental (water quality) and ecological models, separately. Limited studies were developed to couple the two models, and in these limited coupled models, a lake was regarded as a whole for analysis (i.e., considering the lake to be one well-mixed box), which was appropriate for small-scale lakes and was not sufficient to capture spatial variations within middle-scale or large-scale lakes. This paper seeks to establish a zoning-based environmental-ecological-coupled model for a lake. The Baiyangdian Lake, the largest freshwater lake in Northern China, was adopted as the study case. The coupled lake models including a hydrodynamics and water quality model established by MIKE21 and a compartmental ecological model used STELLA software have been established for middle-sized Baiyangdian Lake to realize the simulation of spatial variations of ecological conditions. On the basis of the flow field distribution results generated by MIKE21 hydrodynamics model, four water area zones were used as an example for compartmental ecological model calibration and validation. The results revealed that the developed coupled lake models can reasonably reflected the changes of the key state variables although there remain some state variables that are not well represented by the model due to the low quality of field monitoring data. Monitoring sites in a compartment may not be representative of the water quality and ecological conditions in the entire compartment even though that is the intention of compartment-based model design. There was only one ecological observation from a single monitoring site for some periods. This single-measurement issue may cause large discrepancies particularly when sampled site is not representative of the whole compartment. The coupled models have been applied to simulate the spatial variation trends of ecological condition under ecological water supplement as an example to reflect the application effect in lake restoration and management. The simulation results indicate that the models can provide a useful tool for lake restoration and management. The simulated spatial variation trends can provide a foundation for establishing permissible ranges for a selected set of water quality indices for a series of management measures such as watershed pollution load control and ecological water transfer. Meanwhile, the coupled models can help us to understand processes taking place and the relations of interaction between components in the lake ecosystem and external conditions. Taken together, the proposed models we established show some promising applications as middle-scale or large-scale lake management tools for pollution load control and ecological water transfer. These tools quantify the implications of proposed future water management decisions.

Non-linear effects of drought under shade: reconciling physiological and ecological models in plant communities.

PubMed

Holmgren, Milena; Gómez-Aparicio, Lorena; Quero, José Luis; Valladares, Fernando

2012-06-01

The combined effects of shade and drought on plant performance and the implications for species interactions are highly debated in plant ecology. Empirical evidence for positive and negative effects of shade on the performance of plants under dry conditions supports two contrasting theoretical models about the role of shade under dry conditions: the trade-off and the facilitation hypotheses. We performed a meta-analysis of field and greenhouse studies evaluating the effects of drought at two or more irradiance levels on nine response variables describing plant physiological condition, growth, and survival. We explored differences in plant response across plant functional types, ecosystem types and methodological approaches. The data were best fit using quadratic models indicating a humped-back shape response to drought along an irradiance gradient for survival, whole plant biomass, maximum photosynthetic capacity, stomatal conductance and maximal photochemical efficiency. Drought effects were ameliorated at intermediate irradiance, becoming more severe at higher or lower light levels. This general pattern was maintained when controlling for potential variations in the strength of the drought treatment among light levels. Our quantitative meta-analysis indicates that dense shade ameliorates drought especially among drought-intolerant and shade-tolerant species. Wet tropical species showed larger negative effects of drought with increasing irradiance than semiarid and cold temperate species. Non-linear responses to irradiance were stronger under field conditions than under controlled greenhouse conditions. Non-linear responses to drought along the irradiance gradient reconciliate opposing views in plant ecology, indicating that facilitation is more likely within certain range of environmental conditions, fading under deep shade, especially for drought-tolerant species.

Disease ecology, health and the environment: a framework to account for ecological and socio-economic drivers in the control of neglected tropical diseases

PubMed Central

Sokolow, S. H.; Ngonghala, C. N.; Jocque, M.; Lund, A.; Barry, M.; Mordecai, E. A.; Daily, G. C.; Andrews, J. R.; Bendavid, E.; Luby, S. P.; LaBeaud, A. D.; Seetah, K.; Guégan, J. F.; De Leo, G. A.

2017-01-01

Reducing the burden of neglected tropical diseases (NTDs) is one of the key strategic targets advanced by the Sustainable Development Goals. Despite the unprecedented effort deployed for NTD elimination in the past decade, their control, mainly through drug administration, remains particularly challenging: persistent poverty and repeated exposure to pathogens embedded in the environment limit the efficacy of strategies focused exclusively on human treatment or medical care. Here, we present a simple modelling framework to illustrate the relative role of ecological and socio-economic drivers of environmentally transmitted parasites and pathogens. Through the analysis of system dynamics, we show that periodic drug treatments that lead to the elimination of directly transmitted diseases may fail to do so in the case of human pathogens with an environmental reservoir. Control of environmentally transmitted diseases can be more effective when human treatment is complemented with interventions targeting the environmental reservoir of the pathogen. We present mechanisms through which the environment can influence the dynamics of poverty via disease feedbacks. For illustration, we present the case studies of Buruli ulcer and schistosomiasis, two devastating waterborne NTDs for which control is particularly challenging. This article is part of the themed issue ‘Conservation, biodiversity and infectious disease: scientific evidence and policy implications’. PMID:28438917

Experimentally reducing species abundance indirectly affects food web structure and robustness.

PubMed

Barbosa, Milton; Fernandes, G Wilson; Lewis, Owen T; Morris, Rebecca J

2017-03-01

Studies on the robustness of ecological communities suggest that the loss or reduction in abundance of individual species can lead to secondary and cascading extinctions. However, most such studies have been simulation-based analyses of the effect of primary extinction on food web structure. In a field experiment we tested the direct and indirect effects of reducing the abundance of a common species, focusing on the diverse and self-contained assemblage of arthropods associated with an abundant Brazilian shrub, Baccharis dracunculifolia D.C. (Asteraceae). Over a 5-month period we experimentally reduced the abundance of Baccharopelma dracunculifoliae (Sternorrhyncha: Psyllidae), the commonest galling species associated with B. dracunculifolia, in 15 replicate plots paired with 15 control plots. We investigated direct effects of the manipulation on parasitoids attacking B. dracunculifoliae, as well as indirect effects (mediated via a third species or through the environment) on 10 other galler species and 50 associated parasitoid species. The experimental manipulation significantly increased parasitism on B. dracunculifoliae in the treatment plots, but did not significantly alter either the species richness or abundance of other galler species. Compared to control plots, food webs in manipulated plots had significantly lower values of weighted connectance, interaction evenness and robustness (measured as simulated tolerance to secondary extinction), even when B. dracunculifoliae was excluded from calculations. Parasitoid species were almost entirely specialized to individual galler species, so the observed effects of the manipulation on food web structure could not have propagated via the documented trophic links. Instead, they must have spread either through trophic links not included in the webs (e.g. shared predators) or non-trophically (e.g. through changes in habitat availability). Our results highlight that the inclusion of both trophic and non-trophic direct and indirect interactions is essential to understand the structure and dynamics of even apparently discrete ecological communities. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

More than mere numbers: the impact of lethal control on the social stability of a top-order predator.

PubMed

Wallach, Arian D; Ritchie, Euan G; Read, John; O'Neill, Adam J

2009-09-02

Population control of socially complex species may have profound ecological implications that remain largely invisible if only their abundance is considered. Here we discuss the effects of control on a socially complex top-order predator, the dingo (Canis lupus dingo). Since European occupation of Australia, dingoes have been controlled over much of the continent. Our aim was to investigate the effects of control on their abundance and social stability. We hypothesized that dingo abundance and social stability are not linearly related, and proposed a theoretical model in which dingo populations may fluctuate between three main states: (A) below carrying capacity and socially fractured, (B) above carrying capacity and socially fractured, or (C) at carrying capacity and socially stable. We predicted that lethal control would drive dingoes into the unstable states A or B, and that relaxation of control would allow recovery towards C. We tested our predictions by surveying relative abundance (track density) and indicators of social stability (scent-marking and howling) at seven sites in the arid zone subject to differing degrees of control. We also monitored changes in dingo abundance and social stability following relaxation and intensification of control. Sites where dingoes had been controlled within the previous two years were characterized by low scent-marking activity, but abundance was similar at sites with and without control. Signs of social stability steadily increased the longer an area was allowed to recover from control, but change in abundance did not follow a consistent path. Comparison of abundance and stability among all sites and years demonstrated that control severely fractures social groups, but that the effect of control on abundance was neither consistent nor predictable. Management decisions involving large social predators must therefore consider social stability to ensure their conservation and ecological functioning.

A socio-ecological adaptive approach to contaminated mega-site management: from 'control and correct' to 'coping with change'.

PubMed

Schirmer, Mario; Lyon, Ken; Armstrong, James E; Farrell, Katharine N

2012-01-01

Mega-sites have a notable impact on surrounding ecological systems. At such sites there are substantial risks associated with complex socio-ecological interactions that are hard to characterize, let alone model and predict. While the urge to control and clean-up mega-sites (control and correct) is understandable, rather than setting a goal of cleaning up such sites, we suggest a more realistic response strategy is to address these massive and persistent sources of contamination by acknowledging their position as new features of the socio-ecological landscapes within which they are located. As it seems nearly impossible to clean up such sites, we argue for consideration of a 'coping with change' rather than a 'control and correct' approach. This strategy recognizes that the current management option for a mega-site, in light of its physical complexities and due to changing societal preferences, geochemical transformations, hydrogeology knowledge and remedial technology options may not remain optimal in future, and therefore needs to be continuously adapted, as community, ecology, technology and understanding change over time. This approach creates an opportunity to consider the relationship between a mega-site and its human and ecological environments in a different and more dynamic way. Our proposed approach relies on iterative adaptive management to incorporate mega-site management into the overall socio-ecological systems of the site's context. This approach effectively embeds mega-site management planning in a triple bottom line and environmental sustainability structure, rather than simply using single measures of success, such as contaminant-based guidelines. Recognizing that there is probably no best solution for managing a mega-site, we present a starting point for engaging constructively with this seemingly intractable issue. Therefore, we aim to initiate discussion about a new approach to mega-site management, in which the complexity of the problems posed by mega-sites is reflected upon in its entirety. These complexities are associated with uncertainties and unknowns that have to be addressed, as they have an impact on the strategies being developed and applied. We contend that the best that can be hoped for in mega-site management is an acceptable solution for the current state of affairs, with good flexibility to modify strategies as new site conditions, remediation possibilities, community preferences and management objectives develop over time. Copyright © 2011 Elsevier B.V. All rights reserved.

Analysis of the ecological conservation behavior of farmers in payment for ecosystem service programs in eco-environmentally fragile areas using social psychology models.

PubMed

Deng, Jian; Sun, Pingsheng; Zhao, Fazhu; Han, Xinhui; Yang, Gaihe; Feng, Yongzhong

2016-04-15

Studies on the ecological conservation behavior of farmers usually focus on individual and socio-economic characteristics without consideration of the underlying psychological constructs, such as farmers' intention and perceptions. This study uses the theory of planned behavior (TPB), a typical social psychology construct, to analyze the factors affecting the intention and behavior of farmers for conserving the ecological achievements from payment for ecosystem service (PES) programs in eco-environmentally fragile areas. Questionnaires based on TPB were administered to 1004 farmers from the Grain to Green Program area in the Loess Plateau, China, with the resulting dataset used to identify the underlying factors determining farmers' intention and behavior based on the structural equation model. The results show that the farmers' intention and behavior toward conserving ecological achievements were explained well by TPB. The farmers'behavior was significantly positively affected by their intention toward conserving ecological achievements, and their intention was significantly influenced by their attitude (positive or negative value of performance), the subjective norm (social pressure in engaging behavior), and perceived behavioral control (perceptions of their ability). The farmers' degree of support for PES programs and their recognition of environmental effects were the factors that most influenced the farmers' attitude. Pressure from neighbors was the most potent driver of the subjective norm. Meanwhile, perceptions of their ability to perform the behavior were the most potent factors affecting intention and it was mostly driven by the farmers' feelings toward environmental improvement and perceived ability (time and labor) to participate in ecological conservation. The drivers of attitude, subjective norm, and perceived behavioral control can be used by policy makers to direct farmers' intention and behavior toward conserving ecological achievements in fragile eco-environmentally areas through PES programs. Thus, this strategy can improve the sustainability of ecological and environmental restoration programs. Copyright © 2016 Elsevier B.V. All rights reserved.

Continuous leg dyskinesia assessment in Parkinson's disease -clinical validity and ecological effect.

PubMed

Ramsperger, Robert; Meckler, Stefan; Heger, Tanja; van Uem, Janet; Hucker, Svenja; Braatz, Ulrike; Graessner, Holm; Berg, Daniela; Manoli, Yiannos; Serrano, J Artur; Ferreira, Joaquim J; Hobert, Markus A; Maetzler, Walter

2016-05-01

Dyskinesias in Parkinson's disease (PD) patients are a common side effect of long-term dopaminergic therapy and are associated with motor dysfunctions, including gait and balance deficits. Although promising compounds have been developed to treat these symptoms, clinical trials have failed. This failure may, at least partly, be explained by the lack of objective and continuous assessment strategies. This study tested the clinical validity and ecological effect of an algorithm that detects and quantifies dyskinesias of the legs using a single ankle-worn sensor. Twenty-three PD patients (seven with leg dyskinesias) and 13 control subjects were investigated in the lab. Participants performed purposeful daily activity-like tasks while being video-taped. Clinical evaluation was performed using the leg dyskinesia item of the Unified Dyskinesia Rating Scale. The ecological effect of the developed algorithm was investigated in a multi-center, 12-week, home-based sub-study that included three patients with and seven without dyskinesias. In the lab-based sub-study, the sensor-based algorithm exhibited a specificity of 98%, a sensitivity of 85%, and an accuracy of 0.96 for the detection of dyskinesias and a correlation level of 0.61 (p < 0.001) with the clinical severity score. In the home-based sub-study, all patients could be correctly classified regarding the presence or absence of leg dyskinesias, supporting the ecological relevance of the algorithm. This study provides evidence of clinical validity and ecological effect of an algorithm derived from a single sensor on the ankle for detecting leg dyskinesias in PD patients. These results should motivate the investigation of leg dyskinesias in larger studies using wearable sensors. Copyright © 2016 Elsevier Ltd. All rights reserved.

Ecological-site based assessments of wind and water erosion: informing management of accelerated soil erosion in rangelands

NASA Astrophysics Data System (ADS)

Webb, N.; Herrick, J.; Duniway, M.

2013-12-01

This work explores how soil erosion assessments can be structured in the context of ecological sites and site dynamics to inform systems for managing accelerated soil erosion. We evaluated wind and water erosion rates for five ecological sites in southern New Mexico, USA, using monitoring data and rangeland-specific wind and water erosion models. Our results show that wind and water erosion can be highly variable within and among ecological sites. Plots in shrub-encroached and shrub-dominated states were consistently susceptible to both wind and water erosion. However, grassland plots and plots with a grass-succulent mix had a high indicated susceptibility to wind and water erosion respectively. Vegetation thresholds for controlling erosion are identified that transcend the ecological sites and their respective states. The thresholds define vegetation cover levels at which rapid (exponential) increases in erosion rates begin to occur, suggesting that erosion in the study ecosystem can be effectively controlled when bare ground cover is <20% of a site or total ground cover is >50%. Similarly, our results show that erosion can be controlled when the cover of canopy interspaces >50 cm in length reaches ~50%, the cover of canopy interspaces >100 cm in length reaches ~35% or the cover of canopy interspaces >150 cm in length reaches ~20%. This process-based understanding can be applied, along with knowledge of the differential sensitivity of vegetation states, to improve erosion management systems. Land use and management activities that alter cover levels such that they cross thresholds, and/or drive vegetation state changes, may increase the susceptibility of sites to erosion. Land use impacts that are constrained within the natural variability of sites should not result in accelerated soil erosion. Evaluating land condition against the erosion thresholds and natural variability of ecological sites will enable improved identification of where and when accelerated soil erosion occurs and the development of practical management solutions.

Fire and aquatic ecosystems of the western USA: Current knowledge and key questions

USGS Publications Warehouse

Bisson, P.A.; Rieman, B.; Luce, C.; Hessburg, Paul F.; Lee, D.; Kershner, J.; Reeves, G.H.; Gresswell, Robert E.

2003-01-01

Understanding of the effects of wildland fire and fire management on aquatic and riparian ecosystems is an evolving field, with many questions still to be resolved. Limitations of current knowledge, and the certainty that fire management will continue, underscore the need to summarize available information. Integrating fire and fuels management with aquatic ecosystem conservation begins with recognizing that terrestrial and aquatic ecosystems are linked and dynamic, and that fire can play a critical role in maintaining aquatic ecological diversity. To protect aquatic ecosystems we argue that it will be important to: (1) accommodate fire-related and other ecological processes that maintain aquatic habitats and biodiversity, and not simply control fires or fuels; (2) prioritize projects according to risks and opportunities for fire control and the protection of aquatic ecosystems; and (3) develop new consistency in the management and regulatory process. Ultimately, all natural resource management is uncertain; the role of science is to apply experimental design and hypothesis testing to management applications that affect fire and aquatic ecosystems. Policy-makers and the public will benefit from an expanded appreciation of fire ecology that enables them to implement watershed management projects as experiments with hypothesized outcomes, adequate controls, and replication.

Response to Thomas et al.: Biocontrol and indirect effects

Treesearch

Dean E. Pearson; Ragan M. Callaway

2004-01-01

In a recent TREE article [1], we identified three categories of unintended indirect effects that can arise from host-specific biological control agents: (i) ecological replacement; (ii) compensatory responses; and (iii) food-web interactions. Although our review focused on the biocontrol of plant pests, we suggested these concepts also apply to the biocontrol...

Effects of Plant Traits on Ecosystem and Regional Processes: a Conceptual Framework for Predicting the Consequences of Global Change

PubMed Central

CHAPIN, F. STUART

2003-01-01

Human activities are causing widespread changes in the species composition of natural and managed ecosystems, but the consequences of these changes are poorly understood. This paper presents a conceptual framework for predicting the ecosystem and regional consequences of changes in plant species composition. Changes in species composition have greatest ecological effects when they modify the ecological factors that directly control (and respond to) ecosystem processes. These interactive controls include: functional types of organisms present in the ecosystem; soil resources used by organisms to grow and reproduce; modulators such as microclimate that influence the activity of organisms; disturbance regime; and human activities. Plant traits related to size and growth rate are particularly important because they determine the productive capacity of vegetation and the rates of decomposition and nitrogen mineralization. Because the same plant traits affect most key processes in the cycling of carbon and nutrients, changes in plant traits tend to affect most biogeochemical cycling processes in parallel. Plant traits also have landscape and regional effects through their effects on water and energy exchange and disturbance regime. PMID:12588725

Colony impact of pesticide-induced sublethal effects on honeybee workers: A simulation study using BEEHAVE.

PubMed

Thorbek, Pernille; Campbell, Peter J; Thompson, Helen M

2017-03-01

Research on neonicotinoids and honeybees have changed focus from direct mortality to sublethal effects. In the present study, a published honeybee model, BEEHAVE, is used to compare induced colony level impact of pesticides including direct mortality, poor brood care, disorientation, and increased handling time in oilseed rape and sunflower crops. Actual effects on individual bees will depend on exposure concentrations, but in the present study large effects were enforced. In oilseed rape, poor brood care had the largest colony impact, because it created a bottleneck for spring build-up of the workforce, and colony impact for all effect types peaked 1 mo after exposure ceased. In sunflower, the later exposure changed the response so colony impact peaked during exposure, and the bottleneck was honey store build-up. In all scenarios, good forage mitigated effects substantially. It is concluded that field studies should continue at least 1 mo after exposure to ensure detection of ecologically relevant sublethal effects. The results indicated that even if a sublethal effect is difficult to detect in the field, subsequent ecologically relevant colony level impacts would be clear if studies are continued for 1 mo after exposure. Guidance for regulatory studies recommends extended observation periods, and published field studies already use extended observation periods, so it is concluded that current methods are adequate for detecting ecologically relevant sublethal effects. Although published laboratory and semifield studies conducted under controlled exposure conditions suggest that sublethal effects may occur, published field studies with neonicotinoid seed treatments, naturally foraging bees, and extended observation periods do not report colony-level effects, suggesting that in these studies no ecologically relevant sublethal effects occurred. Environ Toxicol Chem 2017;36:831-840. © 2016 SETAC. © 2016 SETAC.

Mechanism and capacities of reducing ecological cost through rice-duck cultivation.

PubMed

Long, Pan; Huang, Huang; Liao, Xiaolan; Fu, Zhiqiang; Zheng, Huabin; Chen, Aiwu; Chen, Can

2013-09-01

Rice-duck cultivation is the essence of Chinese traditional agriculture. A scientific assessment of the mechanism and its capacity is of theoretical significance and practical value in improving modern agricultural technology. The duck's secretions, excreta and their treading, pecking and predation decrease the occurrence of plant diseases, pests and weeds, enrich species diversity and improve the field environment. The rice-duck intergrowth system effectively prevents rice planthoppers and rice leafhoppers. The control effects can be up to 98.47% and 100% respectively; it also has effects on the control of Chilo suppressalis, Tryporyza incertulas and the rice leafrollers. Notable control results are found on sheath blight, while the effects on other diseases are about 50%. Harm from weeds is placed under primary control; prevention of weeds is sequenced by broadleaf weeds > sedge weeds > Gramineae weeds. Contents of soil organic matter, N, P and K are improved by the system; nutrient utilization is accelerated, resulting in decreased fertilizer application. Greenhouse gas emissions are reduced by 1-2% and duck fodder is saved in this system. There is also an obvious economic benefit. Compared to conventional rice cultivation, rice-duck cultivation shows great benefits to ecologic cost and economic income. © 2013 The Authors. Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Mechanism and capacities of reducing ecological cost through rice–duck cultivation

PubMed Central

Long, Pan; Huang, Huang; Liao, Xiaolan; Fu, Zhiqiang; Zheng, Huabin; Chen, Aiwu; Chen, Can

2013-01-01

BACKGROUND: Rice–duck cultivation is the essence of Chinese traditional agriculture. A scientific assessment of the mechanism and its capacity is of theoretical significance and practical value in improving modern agricultural technology. RESULTS: The duck’s secretions, excreta and their treading, pecking and predation decrease the occurrence of plant diseases, pests and weeds, enrich species diversity and improve the field environment. The rice–duck intergrowth system effectively prevents rice planthoppers and rice leafhoppers. The control effects can be up to 98.47% and 100% respectively; it also has effects on the control of Chilo suppressalis, Tryporyza incertulas and the rice leafrollers. Notable control results are found on sheath blight, while the effects on other diseases are about 50%. Harm from weeds is placed under primary control; prevention of weeds is sequenced by broadleaf weeds > sedge weeds > Gramineae weeds. Contents of soil organic matter, N, P and K are improved by the system; nutrient utilization is accelerated, resulting in decreased fertilizer application. Greenhouse gas emissions are reduced by 1–2% and duck fodder is saved in this system. There is also an obvious economic benefit. CONCLUSION: Compared to conventional rice cultivation, rice–duck cultivation shows great benefits to ecologic cost and economic income. © 2013 The Authors. Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. PMID:23703299

The application of ceramsite ecological floating bed in aquaculture: its effects on water quality, phytoplankton, bacteria and fish production.

PubMed

Li, Xiao-Li; Marella, Thomas Kiran; Tao, Ling; Dai, Li-Li; Peng, Liang; Song, Chao-Feng; Li, Gu

2018-06-01

In recent years, biological floating bed technology has been applied increasingly in aquaculture ponds. In this study we developed a novel floating bed made from ceramsite and studied its effect on water quality, phytoplankton, bacteria and fish growth. Water quality was effectively regulated and controlled in ceramsite floating bed (CFB) ponds with an average transparency of 23.18 cm, ammonia nitrogen (NH 4 + -N) of 2.30 mg L -1 , total nitrogen (TN) of 5.09 mg L -1 and total phosphate (TP) of 1.32 mg L -1 which are lower than in control ponds without CFB. Increased phytoplankton species diversity, bacterial number, metabolic activity and microbial diversity was observed with CFB. At the end of growth stage, feed conversion ratio (FCR) was reduced with a total fish yield of 14,838 kg ha -1 at a survival rate of 77.2% in CFB ponds, which is significantly higher than control (P < 0.05). These results emphasize the potential of ecological floating bed to improve water quality, microalgal diversity, reduce the risk of harmful algal blooms and increase the number, activity and diversity of microorganisms as well as fish yield.

Dietary marker effects on fecal microbial ecology, fecal VFA, nutrient digestibility coefficients, and growth performance in finishing pigs.

PubMed

Kerr, B J; Weber, T E; Ziemer, C J

2015-05-01

Use of indigestible markers such as Cr2O3, Fe2O3, and TiO2 are commonly used in animal studies to evaluate digesta rate of passage and nutrient digestibility. Yet, the potential impact of indigestible markers on fecal microbial ecology and subsequent VFA generation is not known. Two experiments utilizing a total of 72 individually fed finishing pigs were conducted to describe the impact of dietary markers on fecal microbial ecology, fecal ammonia and VFA concentrations, nutrient digestibility, and pig performance. All pigs were fed a common diet with no marker or with 0.5% Cr2O3, Fe2O3, or TiO2. In Exp. 1, after 33 d of feeding, fresh fecal samples were collected for evaluation of microbial ecology, fecal ammonia and VFA concentrations, and nutrient digestibility, along with measures of animal performance. No differences were noted in total microbes or bacterial counts in pig feces obtained from pigs fed the different dietary markers while Archaea counts were decreased (P = 0.07) in feces obtained from pigs fed the diet containing Fe2O 3compared to pigs fed the control diet. Feeding Cr2O3, Fe2O3, or TiO2 increased fecal bacterial richness (P = 0.03, 0.01, and 0.10; respectively) when compared to pigs fed diets containing no marker, but no dietary marker effects were noted on fecal microbial evenness or the Shannon-Wiener index. Analysis of denaturing gradient gel electrophoresis gels did not reveal band pattern alterations due to inclusion of dietary markers in pig diets. There was no effect of dietary marker on fecal DM, ammonia, or VFA concentrations. Pigs fed diets containing Cr2O3 had greater Ca, Cu, Fe, and P (P ≤ 0.02), but lower Ti ( P= 0.08) digestibility compared to pigs fed the control diet. Pigs fed diets containing Fe2O3 had greater Ca (P = 0.08) but lower Ti (P = 0.01) digestibility compared to pigs fed the control diet. Pigs fed diets containing TiO2 had greater Fe and Zn (P ≤ 0.09), but lower Ti ( P= 0.01) digestibility compared to pigs fed the control diet. In Exp. 2, no effect of dietary marker on pig performance was noted. Overall, the data indicate that the inclusion of Cr2O3, Fe2O3, or TiO2 as digestibility markers have little to no impact on microbial ecology, fecal ammonia or VFA concentrations, nutrient digestibility, or pig growth performance indicating they are suitable for use in digestion studies.

Developing integral projection models for aquatic ecotoxicology

EPA Science Inventory

Extrapolating laboratory measured effects of chemicals to ecologically relevant scales is a fundamental challenge in ecotoxicology. In addition to influencing survival in the wild (e.g., over-winter survival) size has been shown to control onset of reproduction for the toxicologi...

Controlled Ecological Life Support Systems: CELSS 1985 Workshop

NASA Technical Reports Server (NTRS)

Macelroy, R. D. (Editor); Martello, N. V. (Editor); Smernoff, D. T. (Editor)

1986-01-01

Various topics related to closed ecological systems are discussed. Space habitats, vegetative growth, photosynthesis, recycling, culture techniques, waste utilization bioreactors and controlled atmospheres on space stations are among the topics covered.

Seafood prices reveal impacts of a major ecological disturbance.

PubMed

Smith, Martin D; Oglend, Atle; Kirkpatrick, A Justin; Asche, Frank; Bennear, Lori S; Craig, J Kevin; Nance, James M

2017-02-14

Coastal hypoxia (dissolved oxygen ≤ 2 mg/L) is a growing problem worldwide that threatens marine ecosystem services, but little is known about economic effects on fisheries. Here, we provide evidence that hypoxia causes economic impacts on a major fishery. Ecological studies of hypoxia and marine fauna suggest multiple mechanisms through which hypoxia can skew a population's size distribution toward smaller individuals. These mechanisms produce sharp predictions about changes in seafood markets. Hypoxia is hypothesized to decrease the quantity of large shrimp relative to small shrimp and increase the price of large shrimp relative to small shrimp. We test these hypotheses using time series of size-based prices. Naive quantity-based models using treatment/control comparisons in hypoxic and nonhypoxic areas produce null results, but we find strong evidence of the hypothesized effects in the relative prices: Hypoxia increases the relative price of large shrimp compared with small shrimp. The effects of fuel prices provide supporting evidence. Empirical models of fishing effort and bioeconomic simulations explain why quantifying effects of hypoxia on fisheries using quantity data has been inconclusive. Specifically, spatial-dynamic feedbacks across the natural system (the fish stock) and human system (the mobile fishing fleet) confound "treated" and "control" areas. Consequently, analyses of price data, which rely on a market counterfactual, are able to reveal effects of the ecological disturbance that are obscured in quantity data. Our results are an important step toward quantifying the economic value of reduced upstream nutrient loading in the Mississippi Basin and are broadly applicable to other coupled human-natural systems.

An Ecological Approach of Constraint Induced Movement Therapy for 2-3-Year-Old Children: A Randomized Control Trial

ERIC Educational Resources Information Center

Eliasson, Ann-Christin; Shaw, Karin; Berg, Elisabeth; Krumlinde-Sundholm, Lena

2011-01-01

The aim was to evaluate the effect of Eco-CIMT in young children with unilateral cerebral palsy in a randomized controlled crossover design. The training was implemented within the regular pediatric services, provided by the child's parents and/or preschool teacher and supervised by the child's regular therapist. Methods: Twenty-five children…

Effects of Supplementation of the Synbiotic Ecologic® 825/FOS P6 on Intestinal Barrier Function in Healthy Humans: A Randomized Controlled Trial

PubMed Central

Wilms, E.; Gerritsen, J.; Smidt, H.; Besseling-van der Vaart, I.; Rijkers, G. T.; Garcia Fuentes, A. R.; Masclee, A. A. M.; Troost, F. J.

2016-01-01

Background and Aims Probiotics, prebiotics and synbiotics have been suggested as dietary strategies to improve intestinal barrier function. This study aimed to assess the effect of two weeks synbiotic supplementation on intestinal permeability under basal and stressed conditions. Secondary aims were the assessment of two weeks synbiotic supplementation on systemic immune function and gastrointestinal symptoms including defecation pattern. Design Twenty healthy adults completed a double-blind, controlled, randomized, parallel design study. Intervention Groups either received synbiotic (1.5 × 1010 CFU Ecologic® 825 + 10 g fructo-oligosaccharides (FOS P6) per day) or control supplements for two weeks. Outcomes Intestinal segment specific permeability was assessed non-invasively by oral administration of multiple sugar probes and, subsequently, assessing the excretion of these probes in urine. This test was conducted at baseline and at the end of intervention, in the absence and in the presence of an indomethacin challenge. Indomethacin was applied to induce a compromised gut state. Plasma zonulin, cytokines and chemokines were measured at baseline and at the end of intervention. Gastrointestinal symptoms and stool frequency were recorded at baseline and daily during intervention. Results Significantly more male subjects were in the synbiotic group compared to the control group (P = 0.025). Indomethacin significantly increased urinary lactulose/rhamnose ratio versus without indomethacin, both in the control group (P = 0.005) and in the synbiotic group (P = 0.017). Urinary sugar recoveries and ratios, plasma levels of zonulin, cytokines and chemokines, and gastrointestinal symptom scores were not significantly different after control or synbiotic intervention. Stool frequency within the synbiotic group was significantly increased during synbiotic intervention compared to baseline (P = 0.039) and higher compared to control intervention (P = 0.045). Conclusion Two weeks Ecologic® 825/FOS P6 supplementation increased stool frequency, but did not affect intestinal permeability neither under basal nor under indomethacin-induced stressed conditions, immune function or gastrointestinal symptoms in healthy adults. PMID:27936169

Effects of Supplementation of the Synbiotic Ecologic® 825/FOS P6 on Intestinal Barrier Function in Healthy Humans: A Randomized Controlled Trial.

PubMed

Wilms, E; Gerritsen, J; Smidt, H; Besseling-van der Vaart, I; Rijkers, G T; Garcia Fuentes, A R; Masclee, A A M; Troost, F J

2016-01-01

Probiotics, prebiotics and synbiotics have been suggested as dietary strategies to improve intestinal barrier function. This study aimed to assess the effect of two weeks synbiotic supplementation on intestinal permeability under basal and stressed conditions. Secondary aims were the assessment of two weeks synbiotic supplementation on systemic immune function and gastrointestinal symptoms including defecation pattern. Twenty healthy adults completed a double-blind, controlled, randomized, parallel design study. Groups either received synbiotic (1.5 × 1010 CFU Ecologic® 825 + 10 g fructo-oligosaccharides (FOS P6) per day) or control supplements for two weeks. Intestinal segment specific permeability was assessed non-invasively by oral administration of multiple sugar probes and, subsequently, assessing the excretion of these probes in urine. This test was conducted at baseline and at the end of intervention, in the absence and in the presence of an indomethacin challenge. Indomethacin was applied to induce a compromised gut state. Plasma zonulin, cytokines and chemokines were measured at baseline and at the end of intervention. Gastrointestinal symptoms and stool frequency were recorded at baseline and daily during intervention. Significantly more male subjects were in the synbiotic group compared to the control group (P = 0.025). Indomethacin significantly increased urinary lactulose/rhamnose ratio versus without indomethacin, both in the control group (P = 0.005) and in the synbiotic group (P = 0.017). Urinary sugar recoveries and ratios, plasma levels of zonulin, cytokines and chemokines, and gastrointestinal symptom scores were not significantly different after control or synbiotic intervention. Stool frequency within the synbiotic group was significantly increased during synbiotic intervention compared to baseline (P = 0.039) and higher compared to control intervention (P = 0.045). Two weeks Ecologic® 825/FOS P6 supplementation increased stool frequency, but did not affect intestinal permeability neither under basal nor under indomethacin-induced stressed conditions, immune function or gastrointestinal symptoms in healthy adults.

Bendectin and birth defects. II: Ecological analyses.

PubMed

Kutcher, Jeffrey S; Engle, Arnold; Firth, Jacqueline; Lamm, Steven H

2003-02-01

Bendectin was the primary pharmaceutical treatment of nausea and vomiting of pregnancy (NVP) in the United States until the early 1980s. Its manufacture was then discontinued after public allegations that it was causing birth defects. Subsequently, meta-analyses of the many epidemiological cohort and case/control studies used to examine that hypothesis have demonstrated the absence of a detectable teratogenic effect. This study presents an ecological analysis of the same hypothesis that examines specific malformations. Annual birth defect prevalence data for the 1970s to the 1990s have been obtained for specific birth defects from the Center for Disease Control's nationwide Birth Defect Monitoring Program. These data for the US have been compared graphically to the annual US Bendectin sales for the treatment of NVP. Data have also been obtained for annual US rates for hospitalization for NVP. The three data sets have been temporally compared in graphic analysis. The temporal trends in prevalence rates for specific birth defects examined from 1970 through 1992 did not show changes that reflected the cessation of Bendectin use over the 1980-84 period. Further, the NVP hospitalization rate doubled when Bendectin use ceased. The population results of the ecological analyses complement the person-specific results of the epidemiological analyses in finding no evidence of a teratogenic effect from the use of Bendectin.

Does Intraspecific Size Variation in a Predator Affect Its Diet Diversity and Top-Down Control of Prey?

PubMed Central

Ingram, Travis; Stutz, William E.; Bolnick, Daniel I.

2011-01-01

It has long been known that intraspecific variation impacts evolutionary processes, but only recently have its potential ecological effects received much attention. Theoretical models predict that genetic or phenotypic variance within species can alter interspecific interactions, and experiments have shown that genotypic diversity in clonal species can impact a wide range of ecological processes. To extend these studies to quantitative trait variation within populations, we experimentally manipulated the variance in body size of threespine stickleback in enclosures in a natural lake environment. We found that body size of stickleback in the lake is correlated with prey size and (to a lesser extent) composition, and that stickleback can exert top-down control on their benthic prey in enclosures. However, a six-fold contrast in body size variance had no effect on the degree of diet variation among individuals, or on the abundance or composition of benthic or pelagic prey. Interestingly, post-hoc analyses revealed suggestive correlations between the degree of diet variation and the strength of top-down control by stickleback. Our negative results indicate that, unless the correlation between morphology and diet is very strong, ecological variation among individuals may be largely decoupled from morphological variance. Consequently we should be cautious in our interpretation both of theoretical models that assume perfect correlations between morphology and diet, and of empirical studies that use morphological variation as a proxy for resource use diversity. PMID:21687670

Does intraspecific size variation in a predator affect its diet diversity and top-down control of prey?

PubMed

Ingram, Travis; Stutz, William E; Bolnick, Daniel I

2011-01-01

It has long been known that intraspecific variation impacts evolutionary processes, but only recently have its potential ecological effects received much attention. Theoretical models predict that genetic or phenotypic variance within species can alter interspecific interactions, and experiments have shown that genotypic diversity in clonal species can impact a wide range of ecological processes. To extend these studies to quantitative trait variation within populations, we experimentally manipulated the variance in body size of threespine stickleback in enclosures in a natural lake environment. We found that body size of stickleback in the lake is correlated with prey size and (to a lesser extent) composition, and that stickleback can exert top-down control on their benthic prey in enclosures. However, a six-fold contrast in body size variance had no effect on the degree of diet variation among individuals, or on the abundance or composition of benthic or pelagic prey. Interestingly, post-hoc analyses revealed suggestive correlations between the degree of diet variation and the strength of top-down control by stickleback. Our negative results indicate that, unless the correlation between morphology and diet is very strong, ecological variation among individuals may be largely decoupled from morphological variance. Consequently we should be cautious in our interpretation both of theoretical models that assume perfect correlations between morphology and diet, and of empirical studies that use morphological variation as a proxy for resource use diversity.

Enlightening Butterfly Conservation Efforts: The Importance of Natural Lighting for Butterfly Behavioral Ecology and Conservation

PubMed Central

2018-01-01

Light is arguably the most important abiotic factor for living organisms. Organisms evolved under specific lighting conditions and their behavior, physiology, and ecology are inexorably linked to light. Understanding light effects on biology could not be more important as present anthropogenic effects are greatly changing the light environments in which animals exist. The two biggest anthropogenic contributors changing light environments are: (1) anthropogenic lighting at night (i.e., light pollution); and (2) deforestation and the built environment. I highlight light importance for butterfly behavior, physiology, and ecology and stress the importance of including light as a conservation factor for conserving butterfly biodiversity. This review focuses on four parts: (1) Introducing the nature and extent of light. (2) Visual and non-visual light reception in butterflies. (3) Implications of unnatural lighting for butterflies across several different behavioral and ecological contexts. (4). Future directions for quantifying the threat of unnatural lighting on butterflies and simple approaches to mitigate unnatural light impacts on butterflies. I urge future research to include light as a factor and end with the hopeful thought that controlling many unnatural light conditions is simply done by flipping a switch. PMID:29439549

Ecological Interface Design for Computer Network Defense.

PubMed

Bennett, Kevin B; Bryant, Adam; Sushereba, Christen

2018-05-01

A prototype ecological interface for computer network defense (CND) was developed. Concerns about CND run high. Although there is a vast literature on CND, there is some indication that this research is not being translated into operational contexts. Part of the reason may be that CND has historically been treated as a strictly technical problem, rather than as a socio-technical problem. The cognitive systems engineering (CSE)/ecological interface design (EID) framework was used in the analysis and design of the prototype interface. A brief overview of CSE/EID is provided. EID principles of design (i.e., direct perception, direct manipulation and visual momentum) are described and illustrated through concrete examples from the ecological interface. Key features of the ecological interface include (a) a wide variety of alternative visual displays, (b) controls that allow easy, dynamic reconfiguration of these displays, (c) visual highlighting of functionally related information across displays, (d) control mechanisms to selectively filter massive data sets, and (e) the capability for easy expansion. Cyber attacks from a well-known data set are illustrated through screen shots. CND support needs to be developed with a triadic focus (i.e., humans interacting with technology to accomplish work) if it is to be effective. Iterative design and formal evaluation is also required. The discipline of human factors has a long tradition of success on both counts; it is time that HF became fully involved in CND. Direct application in supporting cyber analysts.

Engineering stategies and implications of using higher plants for throttling gas and water exchange in a controlled ecological life support system

NASA Technical Reports Server (NTRS)

Chamberland, Dennis; Wheeler, Raymond M.; Corey, Kenneth A.

1993-01-01

Engineering stategies for advanced life support systems to be used on Lunar and Mars bases involve a wide spectrum of approaches. These range from purely physical-chemical life support strategies to purely biological approaches. Within the context of biological based systems, a bioengineered system can be devised that would utilize the metabolic mechanisms of plants to control the rates of CO2 uptake and O2 evolution (photosynthesis) and water production (transpiration). Such a mechanism of external engineering control has become known as throttling. Research conducted at the John F. Kennedy Space Center's Controlled Ecological Life Support System Breadboard Project has demonstrated the potential of throttling these fluxes by changing environmental parameters affecting the plant processes. Among the more effective environmental throttles are: light and CO2 concentration for controllingthe rate of photsynthesis and humidity and CO2 concentration for controlling transpiration. Such a bioengineered strategy implies control mechanisms that in the past have not been widely attributed to life support systems involving biological components and suggests a broad range of applications in advanced life support system design.

El control biologico de plagas(Biological control of pests)

USDA-ARS?s Scientific Manuscript database

In this work some ecological principles that drive applied biocontrol and agent selection are discussed. Subjects such as specificity evaluations, host shifts and species invasiveness are analyzed under the light of ecological theory. The main assertions are: 1. biological control is a safe and bene...

75 FR 76987 - Disease, Disability, and Injury Prevention and Control Special Emphasis Panel (SEP...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-12-10

... DEPARTMENT OF HEALTH AND HUMAN SERVICES Centers for Disease Control and Prevention Disease, Disability, and Injury Prevention and Control Special Emphasis Panel (SEP): Epidemiologic and Ecologic... evaluation of applications received in response to ``Epidemiologic and Ecologic Determinants of Monkeypox in...

Scaling up our understanding of non-consumptive effects in insect systems

DOE PAGES

Hermann, Sara L.; Landis, Douglas A.

2017-04-06

Here, non-consumptive effects (NCEs) of predators on prey is an important topic in insect ecology with potential applications for pest management. NCEs are changes in prey behavior and physiology that aid in predation avoidance. While NCEs can have positive outcomes for prey survival there may also be negative consequences including increased stress and reduced growth. These effects can cascade through trophic systems influencing ecosystem function. Most NCEs have been studied at small spatial and temporal scales. However, recent studies show promise for the potential to manipulate NCEs for pest management. We suggest the next frontier for NCE studies includes manipulatingmore » the landscape of fear to improve pest control, which requires scaling-up to field and landscape levels, over ecologically relevant time frames.« less

Scaling up our understanding of non-consumptive effects in insect systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hermann, Sara L.; Landis, Douglas A.

Here, non-consumptive effects (NCEs) of predators on prey is an important topic in insect ecology with potential applications for pest management. NCEs are changes in prey behavior and physiology that aid in predation avoidance. While NCEs can have positive outcomes for prey survival there may also be negative consequences including increased stress and reduced growth. These effects can cascade through trophic systems influencing ecosystem function. Most NCEs have been studied at small spatial and temporal scales. However, recent studies show promise for the potential to manipulate NCEs for pest management. We suggest the next frontier for NCE studies includes manipulatingmore » the landscape of fear to improve pest control, which requires scaling-up to field and landscape levels, over ecologically relevant time frames.« less

Ecological site-based assessments of wind and water erosion: informing accelerated soil erosion management in rangelands

USGS Publications Warehouse

Webb, Nicholas P.; Herrick, Jeffrey E.; Duniway, Michael C.

2014-01-01

Accelerated soil erosion occurs when anthropogenic processes modify soil, vegetation or climatic conditions causing erosion rates at a location to exceed their natural variability. Identifying where and when accelerated erosion occurs is a critical first step toward its effective management. Here we explore how erosion assessments structured in the context of ecological sites (a land classification based on soils, landscape setting and ecological potential) and their vegetation states (plant assemblages that may change due to management) can inform systems for reducing accelerated soil erosion in rangelands. We evaluated aeolian horizontal sediment flux and fluvial sediment erosion rates for five ecological sites in southern New Mexico, USA, using monitoring data and rangeland-specific wind and water erosion models. Across the ecological sites, plots in shrub-encroached and shrub-dominated vegetation states were consistently susceptible to aeolian sediment flux and fluvial sediment erosion. Both processes were found to be highly variable for grassland and grass-succulent states across the ecological sites at the plot scale (0.25 Ha). We identify vegetation thresholds that define cover levels below which rapid (exponential) increases in aeolian sediment flux and fluvial sediment erosion occur across the ecological sites and vegetation states. Aeolian sediment flux and fluvial erosion in the study area can be effectively controlled when bare ground cover is 100 cm in length is less than ~35%. Land use and management activities that alter cover levels such that they cross thresholds, and/or drive vegetation state changes, may increase the susceptibility of areas to erosion. Land use impacts that are constrained within the range of natural variability should not result in accelerated soil erosion. Evaluating land condition against the erosion thresholds identified here will enable identification of areas susceptible to accelerated soil erosion and the development of practical management solutions.

Forests and competing land uses in Kenya

NASA Astrophysics Data System (ADS)

Allaway, James; Cox, Pamela M. J.

1989-03-01

Indigenous forests in Kenya, as in other developing countries, are under heavy pressure from competing agricultural land uses and from unsustainable cutting. The problem in Kenya is compounded by high population growth rates and an agriculturally based economy, which, even with efforts to control birth rates and industrialize, will persist into the next century. Both ecological and economic consequences of these pressures need to be considered in land-use decision making for land and forest management to be effective. This paper presents one way to combine ecological and economic considerations. The status of principal forest areas in Kenya is summarized and competing land uses compared on the basis of ecological functions and economic analysis. Replacement uses do not match the ecological functions of forest, although established stands of tree crops (forest plantations, fuel wood, tea) can have roughly comparable effects on soil and water resources. Indigenous forests have high, although difficult to estimate, economic benefits from tourism and protection of downstream agricultural productivity. Economic returns from competing land uses range widely, with tea having the highest and fuel wood plantations having returns comparable to some annual crops and dairying. Consideration of ecological and economic factors together suggests some trade-offs for improving land allocation decisions and several management opportunities for increasing benefits or reducing costs from particular land uses. The evaluation also suggests a general strategy for forest land management in Kenya.

Suppressive composts: microbial ecology links between abiotic environments and healthy plants.

PubMed

Hadar, Yitzhak; Papadopoulou, Kalliope K

2012-01-01

Suppressive compost provides an environment in which plant disease development is reduced, even in the presence of a pathogen and a susceptible host. Despite the numerous positive reports, its practical application is still limited. The main reason for this is the lack of reliable prediction and quality control tools for evaluation of the level and specificity of the suppression effect. Plant disease suppression is the direct result of the activity of consortia of antagonistic microorganisms that naturally recolonize the compost during the cooling phase of the process. Thus, it is imperative to increase the level of understanding of compost microbial ecology and population dynamics. This may lead to the development of an ecological theory for complex ecosystems as well as favor the establishment of hypothesis-driven studies.

North American Wetlands and Mosquito Control

PubMed Central

Rey, Jorge R.; Walton, William E.; Wolfe, Roger J.; Connelly, Roxanne; O’Connell, Sheila M.; Berg, Joe; Sakolsky-Hoopes, Gabrielle E.; Laderman, Aimlee D.

2012-01-01

Wetlands are valuable habitats that provide important social, economic, and ecological services such as flood control, water quality improvement, carbon sequestration, pollutant removal, and primary/secondary production export to terrestrial and aquatic food chains. There is disagreement about the need for mosquito control in wetlands and about the techniques utilized for mosquito abatement and their impacts upon wetlands ecosystems. Mosquito control in wetlands is a complex issue influenced by numerous factors, including many hard to quantify elements such as human perceptions, cultural predispositions, and political climate. In spite of considerable progress during the last decades, habitat protection and environmentally sound habitat management still remain inextricably tied to politics and economics. Furthermore, the connections are often complex, and occur at several levels, ranging from local businesses and politicians, to national governments and multinational institutions. Education is the key to lasting wetlands conservation. Integrated mosquito abatement strategies incorporate many approaches and practicable options, as described herein, and need to be well-defined, effective, and ecologically and economically sound for the wetland type and for the mosquito species of concern. The approach will certainly differ in response to disease outbreaks caused by mosquito-vectored pathogens versus quality of life issues caused by nuisance-biting mosquitoes. In this contribution, we provide an overview of the ecological setting and context for mosquito control in wetlands, present pertinent information on wetlands mosquitoes, review the mosquito abatement options available for current wetlands managers and mosquito control professionals, and outline some necessary considerations when devising mosquito control strategies. Although the emphasis is on North American wetlands, most of the material is applicable to wetlands everywhere. PMID:23222252

Controls on vegetation – soil moisture coupling in arid shrublands during drought elicited through long-term data

USDA-ARS?s Scientific Manuscript database

Our goal was to quantify variation in ecological responses to sustained period of moisture limitation (ecological drought) across a semiarid ecological landscape in northern Chihuahuan Desert, USA. We obtained long-term meteorological, ecological site, soil moisture and aboveground net primary prod...

40 CFR 60.4 - Address.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Department of Pollution Control and Ecology, 8001 National Drive, P.O. Box 9583, Little Rock, AR 72209. (F... State Department of Ecology (Ecology), P.O. Box 47600, Olympia, WA 98504-7600, http://www.ecy.wa.gov... not delegated. NSPS Subparts Delegated to Washington Air Agencies Subpart 1 Washington Ecology 2 BCAA...

The Ecological Areawide Management (TEAM) of leafy spurge program of the United States Department of Agriculture-Agricultural Research Service.

PubMed

Anderson, Gerald L; Prosser, Chad W; Wendel, Lloyd E; Delfosse, Ernest S; Faust, Robert M

2003-01-01

The Ecological Areawide Management (TEAM) of Leafy Spurge program was developed to focus research and control efforts on a single weed, leafy spurge, and demonstrate the effectiveness of a coordinated, biologically based, integrated pest management program (IPM). This was accomplished through partnerships and teamwork that clearly demonstrated the advantages of the biologically based IPM approach. However, the success of regional weed control programs horizontally across several states and provinces also requires a vertical integration of several sectors of society. Awareness and education are the essential elements of vertical integration. Therefore, a substantial effort was made to produce a wide variety of information products specifically designed to educate different segments of society. During its tenure, land managers and agency decision makers have seen the potential of using the TEAM approach to accelerate the regional control of leafy spurge. The example set by the TEAM organization and participants is viewed as a model for future weed-control efforts.

Pest control of aphids depends on landscape complexity and natural enemy interactions

PubMed Central

Reineking, Björn; Seo, Bumsuk; Steffan-Dewenter, Ingolf

2015-01-01

Aphids are a major concern in agricultural crops worldwide, and control by natural enemies is an essential component of the ecological intensification of agriculture. Although the complexity of agricultural landscapes is known to influence natural enemies of pests, few studies have measured the degree of pest control by different enemy guilds across gradients in landscape complexity. Here, we use multiple natural-enemy exclosures replicated in 18 fields across a gradient in landscape complexity to investigate (1) the strength of natural pest control across landscapes, measured as the difference between pest pressure in the presence and in the absence of natural enemies; (2) the differential contributions of natural enemy guilds to pest control, and the nature of their interactions across landscapes. We show that natural pest control of aphids increased up to six-fold from simple to complex landscapes. In the absence of pest control, aphid population growth was higher in complex than simple landscapes, but was reduced by natural enemies to similar growth rates across all landscapes. The effects of enemy guilds were landscape-dependent. Particularly in complex landscapes, total pest control was supplied by the combined contribution of flying insects and ground-dwellers. Birds had little overall impact on aphid control. Despite evidence for intraguild predation of flying insects by ground-dwellers and birds, the overall effect of enemy guilds on aphid control was complementary. Understanding pest control services at large spatial scales is critical to increase the success of ecological intensification schemes. Our results suggest that, where aphids are the main pest of concern, interactions between natural enemies are largely complementary and lead to a strongly positive effect of landscape complexity on pest control. Increasing the availability of seminatural habitats in agricultural landscapes may thus benefit not only natural enemies, but also the effectiveness of aphid natural pest control. PMID:26734497

Pest control of aphids depends on landscape complexity and natural enemy interactions.

PubMed

Martin, Emily A; Reineking, Björn; Seo, Bumsuk; Steffan-Dewenter, Ingolf

2015-01-01

Aphids are a major concern in agricultural crops worldwide, and control by natural enemies is an essential component of the ecological intensification of agriculture. Although the complexity of agricultural landscapes is known to influence natural enemies of pests, few studies have measured the degree of pest control by different enemy guilds across gradients in landscape complexity. Here, we use multiple natural-enemy exclosures replicated in 18 fields across a gradient in landscape complexity to investigate (1) the strength of natural pest control across landscapes, measured as the difference between pest pressure in the presence and in the absence of natural enemies; (2) the differential contributions of natural enemy guilds to pest control, and the nature of their interactions across landscapes. We show that natural pest control of aphids increased up to six-fold from simple to complex landscapes. In the absence of pest control, aphid population growth was higher in complex than simple landscapes, but was reduced by natural enemies to similar growth rates across all landscapes. The effects of enemy guilds were landscape-dependent. Particularly in complex landscapes, total pest control was supplied by the combined contribution of flying insects and ground-dwellers. Birds had little overall impact on aphid control. Despite evidence for intraguild predation of flying insects by ground-dwellers and birds, the overall effect of enemy guilds on aphid control was complementary. Understanding pest control services at large spatial scales is critical to increase the success of ecological intensification schemes. Our results suggest that, where aphids are the main pest of concern, interactions between natural enemies are largely complementary and lead to a strongly positive effect of landscape complexity on pest control. Increasing the availability of seminatural habitats in agricultural landscapes may thus benefit not only natural enemies, but also the effectiveness of aphid natural pest control.

40 CFR 52.181 - Significant deterioration of air quality.

Code of Federal Regulations, 2010 CFR

2010-07-01

...”) submitted April 23, 1981 (as adopted by the Arkansas Commission on Pollution Control and Ecology (ACPCE) on... the Arkansas Pollution Control and Ecology Commission on January 22, 1999) (b) The requirements of...

40 CFR 52.181 - Significant deterioration of air quality.

Code of Federal Regulations, 2011 CFR

2011-07-01

...”) submitted April 23, 1981 (as adopted by the Arkansas Commission on Pollution Control and Ecology (ACPCE) on... the Arkansas Pollution Control and Ecology Commission on January 22, 1999) (b) The requirements of...

The effects of run-of-river hydroelectric power schemes on invertebrate community composition in temperate streams and rivers.

PubMed

Bilotta, Gary S; Burnside, Niall G; Turley, Matthew D; Gray, Jeremy C; Orr, Harriet G

2017-01-01

Run-of-river (ROR) hydroelectric power (HEP) schemes are often presumed to be less ecologically damaging than large-scale storage HEP schemes. However, there is currently limited scientific evidence on their ecological impact. The aim of this article is to investigate the effects of ROR HEP schemes on communities of invertebrates in temperate streams and rivers, using a multi-site Before-After, Control-Impact (BACI) study design. The study makes use of routine environmental surveillance data collected as part of long-term national and international monitoring programmes at 22 systematically-selected ROR HEP schemes and 22 systematically-selected paired control sites. Five widely-used family-level invertebrate metrics (richness, evenness, LIFE, E-PSI, WHPT) were analysed using a linear mixed effects model. The analyses showed that there was a statistically significant effect (p<0.05) of ROR HEP construction and operation on the evenness of the invertebrate community. However, no statistically significant effects were detected on the four other metrics of community composition. The implications of these findings are discussed in this article and recommendations are made for best-practice study design for future invertebrate community impact studies.

The effects of run-of-river hydroelectric power schemes on invertebrate community composition in temperate streams and rivers

PubMed Central

2017-01-01

Run-of-river (ROR) hydroelectric power (HEP) schemes are often presumed to be less ecologically damaging than large-scale storage HEP schemes. However, there is currently limited scientific evidence on their ecological impact. The aim of this article is to investigate the effects of ROR HEP schemes on communities of invertebrates in temperate streams and rivers, using a multi-site Before-After, Control-Impact (BACI) study design. The study makes use of routine environmental surveillance data collected as part of long-term national and international monitoring programmes at 22 systematically-selected ROR HEP schemes and 22 systematically-selected paired control sites. Five widely-used family-level invertebrate metrics (richness, evenness, LIFE, E-PSI, WHPT) were analysed using a linear mixed effects model. The analyses showed that there was a statistically significant effect (p<0.05) of ROR HEP construction and operation on the evenness of the invertebrate community. However, no statistically significant effects were detected on the four other metrics of community composition. The implications of these findings are discussed in this article and recommendations are made for best-practice study design for future invertebrate community impact studies. PMID:28158282

Ecological effects of the Wickersham Dome fire near Fairbanks, Alaska.

Treesearch

L.A. Viereck; C.T. Dyrness

1979-01-01

The Wickersham Dome fire occurred in late June 1971 and burned over 6 300 hectares of predominantly black spruce forest land. Shortly after the fire was controlled, studies of the effects of the fire on various components of the biotic community were undertaken. Results reported here are mainly for the first 3 years after the fire.

Action versus Result-Oriented Schemes in a Grassland Agroecosystem: A Dynamic Modelling Approach

PubMed Central

Sabatier, Rodolphe; Doyen, Luc; Tichit, Muriel

2012-01-01

Effects of agri-environment schemes (AES) on biodiversity remain controversial. While most AES are action-oriented, result-oriented and habitat-oriented schemes have recently been proposed as a solution to improve AES efficiency. The objective of this study was to compare action-oriented, habitat-oriented and result-oriented schemes in terms of ecological and productive performance as well as in terms of management flexibility. We developed a dynamic modelling approach based on the viable control framework to carry out a long term assessment of the three schemes in a grassland agroecosystem. The model explicitly links grazed grassland dynamics to bird population dynamics. It is applied to lapwing conservation in wet grasslands in France. We ran the model to assess the three AES scenarios. The model revealed the grazing strategies respecting ecological and productive constraints specific to each scheme. Grazing strategies were assessed by both their ecological and productive performance. The viable control approach made it possible to obtain the whole set of viable grazing strategies and therefore to quantify the management flexibility of the grassland agroecosystem. Our results showed that habitat and result-oriented scenarios led to much higher ecological performance than the action-oriented one. Differences in both ecological and productive performance between the habitat and result-oriented scenarios were limited. Flexibility of the grassland agroecosystem in the result-oriented scenario was much higher than in that of habitat-oriented scenario. Our model confirms the higher flexibility as well as the better ecological and productive performance of result-oriented schemes. A larger use of result-oriented schemes in conservation may also allow farmers to adapt their management to local conditions and to climatic variations. PMID:22496746

The short-term effects of three molluscicides on the microflora and microfauna of small, biologically stable ponds in Southern Rhodesia.

PubMed

SHIFF, C J; GARNETT, B

1961-01-01

Where large-scale molluscicide applications are anticipated, it is important to investigate the effects of the chemicals to be used on the freshwater microflora and fauna existing in the bodies of water to be treated. The food chains of which these organisms form basic parts are important in the general ecology leading up to fish and even to man. Some observations on the direct short-term effect of three molluscicides-copper sulfate, sodium pentachlorophenate and Bayer 73-on the populations of certain plankton organisms, carried out in biologically stable ponds in Southern Rhodesia, are reported on in this paper. It appears that copper sulfate has the most drastic and long-lasting effects on these organisms. The authors stress that snail control measures involving molluscicides should be so designed as to effect the minimum alteration to the ecological balance of the freshwater habitat.

Will Culling White-Tailed Deer Prevent Lyme Disease?

PubMed

Kugeler, K J; Jordan, R A; Schulze, T L; Griffith, K S; Mead, P S

2016-08-01

White-tailed deer play an important role in the ecology of Lyme disease. In the United States, where the incidence and geographic range of Lyme disease continue to increase, reduction of white-tailed deer populations has been proposed as a means of preventing human illness. The effectiveness of this politically sensitive prevention method is poorly understood. We summarize and evaluate available evidence regarding the effect of deer reduction on vector tick abundance and human disease incidence. Elimination of deer from islands and other isolated settings can have a substantial impact on the reproduction of blacklegged ticks, while reduction short of complete elimination has yielded mixed results. To date, most studies have been conducted in ecologic situations that are not representative to the vast majority of areas with high human Lyme disease risk. Robust evidence linking deer control to reduced human Lyme disease risk is lacking. Currently, there is insufficient evidence to recommend deer population reduction as a Lyme disease prevention measure, except in specific ecologic circumstances. © 2015 Blackwell Verlag GmbH.

Ecological and evolutionary drivers of the elevational gradient of diversity.

PubMed

Laiolo, Paola; Pato, Joaquina; Obeso, José Ramón

2018-05-02

Ecological, evolutionary, spatial and neutral theories make distinct predictions and provide distinct explanations for the mechanisms that control the relationship between diversity and the environment. Here, we test predictions of the elevational diversity gradient focusing on Iberian bumblebees, grasshoppers and birds. Processes mediated by local abundance and regional diversity concur in explaining local diversity patterns along elevation. Effects expressed through variation in abundance were similar among taxa and point to the overriding role of a physical factor, temperature. This determines how energy is distributed among individuals and ultimately how the resulting pattern of abundance affects species incidence. Effects expressed through variation in regional species pools depended instead on taxon-specific evolutionary history, and lead to diverging responses under similar environmental pressures. Local filters and regional variation also explain functional diversity gradients, in line with results from species richness that indicate an (local) ecological and (regional) historical unfolding of diversity-elevation relationships. © 2018 John Wiley & Sons Ltd/CNRS.

Ecology and policy for exclusive breastfeeding in Colombia: a proposal

PubMed Central

2012-01-01

Introduction: Breastfeeding promotion is one of the most important strategies against infant mortality and to control child undernourishment. Despite policies and plans to promote and protect breastfeeding in Colombia, its practice is low and its duration is short. Objective: To propose an ecology framework to interpret and incorporate contextual, interpersonal, and individual factors associated with the practice of breastfeeding and duration. Thereby, the plans and policies addressed to promote and protect breastfeeding in Colombia could be reinforced. Conclusions: To implement an ecology framework for Breastfeeding in Colombia, it is necessary to identify the effect of contextual factors in the biggest cultural regions of Colombia, to recognize the limitations of Infant-Friendly Hospital Initiatives to improve exclusive breastfeeding duration, to execute prospective studies in order to identify factors associated with breastfeeding duration, to design and implement plans and policies based on comprehensive planning strategies of healthcare interventions, to develop appropriate and cost-effective extra-institutional strategies aimed at prolonging the duration of breastfeeding, and to implement more reliable breastfeeding surveillance systems. PMID:24893193

Will Culling White-Tailed Deer Prevent Lyme Disease?

PubMed Central

Kugeler, K. J.; Jordan, R. A.; Schulze, T. L.; Griffith, K. S.; Mead, P. S.

2015-01-01

Summary White-tailed deer play an important role in the ecology of Lyme disease. In the United States, where the incidence and geographic range of Lyme disease continue to increase, reduction of white-tailed deer populations has been proposed as a means of preventing human illness. The effectiveness of this politically sensitive prevention method is poorly understood. We summarize and evaluate available evidence regarding the effect of deer reduction on vector tick abundance and human disease incidence. Elimination of deer from islands and other isolated settings can have a substantial impact on the reproduction of blacklegged ticks, while reduction short of complete elimination has yielded mixed results. To date, most studies have been conducted in ecologic situations that are not representative to the vast majority of areas with high human Lyme disease risk. Robust evidence linking deer control to reduced human Lyme disease risk is lacking. Currently, there is insufficient evidence to recommend deer population reduction as a Lyme disease prevention measure, except in specific ecologic circumstances. PMID:26684932

Making Youth Tobacco Control Programs More Ecological: Organizational and Professional Profiles.

ERIC Educational Resources Information Center

Richard, Lucie; Gauvin, Lise; Potvin, Louise; Denis, Jean-Louis; Kishchuk, Natalie

2002-01-01

Examined organizational and professional correlates of the integration of the ecological approach in Canadian public health organizations' youth tobacco control programs. Surveys of 110 tobacco control programs in 90 organizations indicated that organizational environment and staff preparation played a critical role in adoption of the ecological…

Simulating ecological changes caused by marine energy devices

NASA Astrophysics Data System (ADS)

Schuchert, Pia; Elsaesser, Bjoern; Pritchard, Daniel; Kregting, Louise

2015-04-01

Marine renewable energy from wave and tidal technology has the potential to contribute significantly globally to energy security for future generations. However common to both tidal and wave energy extraction systems is concern regarding the potential environmental consequences of the deployment of the technology as environmental and ecological effects are so far poorly understood. Ecological surveys and studies to investigate the environmental impacts are time consuming and costly and are generally reactive; a more efficient approach is to develop 2 and 3D linked hydrodynamic-ecological modelling which has the potential to be proactive and to allow forecasting of the effects of array installation. The objective of the study was to explore tools which can help model and evaluate possible far- and near field changes in the environment and ecosystem caused by the introduction of arrays of marine energy devices. Using the commercial software, MIKE by DHI, we can predict and model possible changes in the ecosystem. MIKE21 and ECOLab modelling software provide the opportunity to couple high level hydrodynamic models with process based ecological models and/or agent based models (ABM). The flow solutions of the model were determined in an idealised tidal basin with the dimensions similar to that of Strangford Lough, Northern Ireland, a body of water renowned for the location of the first grid-connected tidal turbine, SeaGen. In the first instance a simple process oriented ecological NPZD model was developed which are used to model marine and freshwater systems describing four state variables, Nutrient, Phytoplankton, Zooplankton and Detritus. The ecological model was run and evaluated under two hydrodynamic scenarios of the idealised basin. This included no tidal turbines (control) and an array of 55 turbines, an extreme scenario. Whilst an array of turbines has an effect on the hydrodynamics of the Lough, it is unlikely to see an extreme effect on the NPZD model. Further assessment on primary productivity and filter feeders is currently being implemented to assess impacts on these biological systems. Using MIKE software opens up many further possibilities to allow insights into the impacts of marine energy devices on the ecosystem.

Allelochemical Control of Non-Indigenous Invasive Plant Species Affecting Military Testing and Training Activities

DTIC Science & Technology

2010-10-01

Evolution in invasive plants : implications for biological control. Trends in Ecology & Evolution . 19:417-422. Newingham, B.A. and R.M. Callaway...2008. Soil ecological interactions of spotted knapweed and native plant species. M.S. Thesis. Colorado State University. Fort Collins, CO...weapons and exotic plant invasions. NSF workshop on ecology and biochemical interactions , Lima. Peru. May. Keynote presentation. Callaway, R.M

Ecological studies related to the construction of the Defense Waste Processing Facility on the Savannah River Site. Annual report, FY-1991 and FY-1992

DOE Office of Scientific and Technical Information (OSTI.GOV)

Scott, D.E.; Chazel, A.C.; Pechmann, J.H.K.

1993-06-01

The Defense Waste Processing Facility (DWPF) was built on the Savannah River Site (SRS) during the mid-1980`s. The Savannah River Ecology Laboratory (SREL) has completed 14 years of ecological studies related to the construction of the DWPF complex. Prior to construction, the 600-acre site (S-Area) contained a Carolina bay and the headwaters of a stream. Research conducted by the SREL has focused primarily on four questions related to these wetlands: (1) Prior to construction, what fauna and flora were present at the DWPF site and at similar, yet undisturbed, alternative sites? (2) By comparing the Carolina bay at the DWPFmore » site (Sun Bay) with an undisturbed control Carolina bay (Rainbow Bay), what effect is construction having on the organisms that inhabited the DWPF site? (3) By comparing control streams with streams on the periphery of the DWPF site, what effect is construction having on the peripheral streams? (4) How effective have efforts been to lessen the impacts of construction, both with respect to erosion control measures and the construction of ``refuge ponds`` as alternative breeding sites for amphibians that formerly bred at Sun Bay? Through the long-term census-taking of biota at the DWPF site and Rainbow Bay, SREL has begun to evaluate the impact of construction on the biota and the effectiveness of mitigation efforts. Similarly, the effects of erosion from the DWPF site on the water quality of S-Area peripheral streams are being assessed. This research provides supporting data relevant to the National Environmental Policy Act (NEPA) of 1969, the Endangered Species Act of 1973, Executive Orders 11988 (Floodplain Management) and 11990 (Protection of Wetlands), and United States Department of Energy (DOE) Guidelines for Compliance with Floodplain/Wetland Environmental Review Requirements (10 CFR 1022).« less

The ecology of microorganisms in a small closed system: Potential benefits and problems for space station

NASA Technical Reports Server (NTRS)

Rodgers, E. B.

1986-01-01

The inevitble presence on the space station of microorganisms associated with crew members and their environment will have the potential for both benefits and a range of problems including illness and corrosion of materials. This report reviews the literature presenting information about microorganisms pertinent to Environmental Control and Life Support (ECLS) on the space station. The perspective of the report is ecological, viewing the space station as an ecosystem in which biological relationships are affected by factors such as zero gravity and by closure of a small volume of space. Potential sites and activities of microorganisms on the space station and their environmental limits, microbial standards for the space station, monitoring and control methods, effects of space factors on microorganisms, and extraterrestrial contamination are discussed.

Disease ecology, health and the environment: a framework to account for ecological and socio-economic drivers in the control of neglected tropical diseases.

PubMed

Garchitorena, A; Sokolow, S H; Roche, B; Ngonghala, C N; Jocque, M; Lund, A; Barry, M; Mordecai, E A; Daily, G C; Jones, J H; Andrews, J R; Bendavid, E; Luby, S P; LaBeaud, A D; Seetah, K; Guégan, J F; Bonds, M H; De Leo, G A

2017-06-05

Reducing the burden of neglected tropical diseases (NTDs) is one of the key strategic targets advanced by the Sustainable Development Goals. Despite the unprecedented effort deployed for NTD elimination in the past decade, their control, mainly through drug administration, remains particularly challenging: persistent poverty and repeated exposure to pathogens embedded in the environment limit the efficacy of strategies focused exclusively on human treatment or medical care. Here, we present a simple modelling framework to illustrate the relative role of ecological and socio-economic drivers of environmentally transmitted parasites and pathogens. Through the analysis of system dynamics, we show that periodic drug treatments that lead to the elimination of directly transmitted diseases may fail to do so in the case of human pathogens with an environmental reservoir. Control of environmentally transmitted diseases can be more effective when human treatment is complemented with interventions targeting the environmental reservoir of the pathogen. We present mechanisms through which the environment can influence the dynamics of poverty via disease feedbacks. For illustration, we present the case studies of Buruli ulcer and schistosomiasis, two devastating waterborne NTDs for which control is particularly challenging.This article is part of the themed issue 'Conservation, biodiversity and infectious disease: scientific evidence and policy implications'. © 2017 The Author(s).

Oxygen, ecology, and the Cambrian radiation of animals

PubMed Central

Sperling, Erik A.; Frieder, Christina A.; Raman, Akkur V.; Girguis, Peter R.; Levin, Lisa A.; Knoll, Andrew H.

2013-01-01

The Proterozoic-Cambrian transition records the appearance of essentially all animal body plans (phyla), yet to date no single hypothesis adequately explains both the timing of the event and the evident increase in diversity and disparity. Ecological triggers focused on escalatory predator–prey “arms races” can explain the evolutionary pattern but not its timing, whereas environmental triggers, particularly ocean/atmosphere oxygenation, do the reverse. Using modern oxygen minimum zones as an analog for Proterozoic oceans, we explore the effect of low oxygen levels on the feeding ecology of polychaetes, the dominant macrofaunal animals in deep-sea sediments. Here we show that low oxygen is clearly linked to low proportions of carnivores in a community and low diversity of carnivorous taxa, whereas higher oxygen levels support more complex food webs. The recognition of a physiological control on carnivory therefore links environmental triggers and ecological drivers, providing an integrated explanation for both the pattern and timing of Cambrian animal radiation. PMID:23898193

Treatment of CELSS and PCELSS waste to produce nutrients for plant growth. [Controlled Ecological Life Support Systems and Partially Controlled Ecological Life Support Systems

NASA Technical Reports Server (NTRS)

Modell, M.; Meissner, H.; Karel, M.; Carden, J.; Lewis, S.

1981-01-01

The research program entitled 'Development of a Prototype Experiment for Treating CELSS (Controlled Ecological Life Support Systems) and PCELSS (Partially Controlled Ecological Life Support Systems) Wastes to Produce Nutrients for Plant Growth' consists of two phases: (1) the development of the neccessary facilities, chemical methodologies and models for meaningful experimentation, and (2) the application of what methods and devices are developed to the interfacing of waste oxidation with plant growth. Homogeneous samples of freeze-dried human feces and urine have been prepared to ensure comparability of test results between CELSS waste treatment research groups. A model of PCELSS food processing wastes has been developed, and an automated gas chromatographic system to analyze oxidizer effluents was designed and brought to operational status. Attention is given the component configuration of the wet oxidation system used by the studies.

Translating ecology, physiology, biochemistry and population genetics research to meet the challenge of tick and tick-borne diseases in North America

PubMed Central

Esteve-Gassent, Maria D.; Castro-Arellano, Ivan; Feria-Arroyo, Teresa P.; Patino, Ramiro; Li, Andrew Y.; Medina, Raul F.; Pérez de León, Adalberto A.; Rodríguez-Vivas, Roger Iván

2016-01-01

Emerging and re-emerging tick-borne diseases threaten public health and the wellbeing of domestic animals and wildlife globally. The adoption of an evolutionary ecology framework aimed to diminish the impact of tick-borne diseases needs to be part of strategies to protect human and animal populations. We present a review of current knowledge on the adaptation of ticks to their environment, and the impact that global change could have on their geographic distribution in North America. Environmental pressures will affect tick population genetics by selecting genotypes able to withstand new and changing environments and by altering the connectivity and isolation of several tick populations. Research in these areas is particularly lacking in the southern US and most of Mexico with knowledge gaps on the ecology of these diseases, including a void in the identity of reservoir hosts for several tick-borne pathogens. Additionally, the way in which anthropogenic changes to landscapes may influence tick-borne disease ecology remains to be fully understood. Enhanced knowledge in these areas is needed in order to implement effective and sustainable integrated tick management strategies. We propose to refocus ecology studies with emphasis on metacommunity-based approaches to enable a holistic perspective addressing whole pathogen and host assemblages. Network analyses could be used to develop mechanistic models involving multi host-pathogen communities. An increase in our understanding of the ecology of tick-borne diseases across their geographic distribution will aid in the design of effective area-wide tick control strategies aimed to diminish the burden of pathogens transmitted by ticks. PMID:27062414

The Effectiveness of Exercise Intervention on Inhibitory Control in Children with Developmental Coordination Disorder: Using a Visuospatial Attention Paradigm as a Model

ERIC Educational Resources Information Center

Tsai, Chia-Liang

2009-01-01

Children with developmental coordination disorder (DCD) have been demonstrated to show a deficit of inhibitory control in volitional shifts of attention. The aim of this study was to use ecological intervention to investigate the efficacy of table-tennis training on treating both problems with attentional networks and motor disorder in children…

Core Principles of Bacterial Autoinducer Systems

PubMed Central

2015-01-01

SUMMARY Autoinduction (AI), the response to self-produced chemical signals, is widespread in the bacterial world. This process controls vastly different target functions, such as luminescence, nutrient acquisition, and biofilm formation, in different ways and integrates additional environmental and physiological cues. This diversity raises questions about unifying principles that underlie all AI systems. Here, we suggest that such core principles exist. We argue that the general purpose of AI systems is the homeostatic control of costly cooperative behaviors, including, but not limited to, secreted public goods. First, costly behaviors require preassessment of their efficiency by cheaper AI signals, which we encapsulate in a hybrid “push-pull” model. The “push” factors cell density, diffusion, and spatial clustering determine when a behavior becomes effective. The relative importance of each factor depends on each species' individual ecological context and life history. In turn, “pull” factors, often stress cues that reduce the activation threshold, determine the cellular demand for the target behavior. Second, control is homeostatic because AI systems, either themselves or through accessory mechanisms, not only initiate but also maintain the efficiency of target behaviors. Third, AI-controlled behaviors, even seemingly noncooperative ones, are generally cooperative in nature, when interpreted in the appropriate ecological context. The escape of individual cells from biofilms, for example, may be viewed as an altruistic behavior that increases the fitness of the resident population by reducing starvation stress. The framework proposed here helps appropriately categorize AI-controlled behaviors and allows for a deeper understanding of their ecological and evolutionary functions. PMID:25694124

EMIRA: Ecologic Malaria Reduction for Africa--innovative tools for integrated malaria control.

PubMed

Dambach, Peter; Traoré, Issouf; Becker, Norbert; Kaiser, Achim; Sié, Ali; Sauerborn, Rainer

2014-01-01

Malaria control is based on early treatment of cases and on vector control. The current measures for malaria vector control in Africa are mainly based on long-lasting insecticide treated nets (LLINs) and to a much smaller extent on indoor residual spraying (IRS). A third pillar in the fight against the malaria vector, larval source management (LSM), has virtually not been used in Africa since the ban of DDT in the 1960s. Within the light of recent WHO recommendations for Bacillus thuringiensis israelensis (Bti) use against malaria and other vector species, larval source management could see a revival in the upcoming years. In this project we analyze the ecologic and health impacts as well as the cost effectiveness of larval source management under different larviciding scenarios in a health district in Burkina Faso. The project is designed as prospective intervention study with duration of three years (2013-2015). Its spatial scale includes three arms of interventions and control, comprising a total of 127 villages and the district capital Nouna in the extended HDSS (Health Demographic Surveillance System) of the Kossi province. Baseline data on mosquito abundance, parasitemia in U5 children, and malaria related morbidity and mortality are gathered over the project duration. Besides the outcome on ecologic and health parameters, the economic costs are seized and valued against the achieved health benefits. Risk map based, guided larvicide application might be a possibility to further decrease economic cost of LSM and facilitate its faster incorporation to integrated malaria control programs. Given the limited resources in many malaria endemic countries, it is of utmost importance to relate the costs of novel strategies for malaria prevention to their effect on the burden of the disease. Occurring costs and the impact on the health situation will be made comparable to other, existing intervention strategies, allowing stakeholders and policymakers decision making.

Mineral separation and recycle in a Controlled Ecological Life Support System (CELSS)

NASA Technical Reports Server (NTRS)

Ballou, E. V.

1982-01-01

The background of the mineral nutrition needs of plants are examined along with the applicability of mineral control and separation to a controlled ecological life support system (CELSS). Steps that may be taken in a program to analytically define and experimentally test key mineral control concepts in the nutritional and waste processing loops of a CELSS are delineated.

TRADING ALLOWANCES FOR STORMWATER CONTROL: HYDROLOGY AND OPPORTUNITY COSTS

EPA Science Inventory

Excess stormwater runoff is a serious problem in a large number of urban areas, causing flooding, water pollution, groundwater recharge deficits and ecological damage to urban streams. It has been posited that to mitigate the effects of excess stormwater runoff, policy makers...

TRADING ALLOWANCES FOR STORMWATER CONTROL: HYDROLOGY AND OPPORTUNITY COSTS

EPA Science Inventory

Excess stormwater runoff is a serious problem in a large number of urban areas, causing flooding, water pollution, groundwater recharge deficits and ecological damage to urban streams. It has been posited that to mitigate the effects of excess stormwater runoff, policy makers cou...

Response mechanisms of conifers to air pollutants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matyssek, R.; Reich, P.; Oren, R.

1995-07-01

Conifers are known to respond to SO{sub 2}, O{sub 3}, NO{sub x} and acid deposition. Of these pollutants, O{sub 3} is likely the most widespread and phytotoxic compound, and therefore of great interest to individuals concerned with forest resources Direct biological responses have a toxicological effects on metabolism which can then scale to effects on tree growth and forest ecology, including processes of competition and succession. Air pollution can cause reductions in photosynthesis and stomatal conductance, which are the physiological parameters most rigorously studied for conifers. Some effects air pollutants can have on plants are influenced by the presence ofmore » co-occurring environmental stresses. For example, drought usually reduces vulnerability of plants to air pollution. In addition, air pollution sensitivity may differ among species and with plant/leaf age. Plants may make short-term physiological adjustments to compensate for air pollution or may evolve resistance to air pollution through the processes of selection. Models are necessary to understand how physiological processes, growth processes, and ecological processes are affected by air pollutants. The process of defining the ecological risk that air pollutants pose for coniferous forests requires approaches that exploit existing databases, environmental monitoring of air pollutants and forest resources, experiments with well-defined air pollution treatments and environmental control/monitoring, modeling, predicting air pollution-caused changes in productivity and ecological processes over time and space, and integration of social values.« less

From State-controlled to Polycentric Governance in Forest Landscape Restoration: The Case of the Ecological Forest Purchase Program in Yong'an Municipality of China.

PubMed

Long, Hexing; Liu, Jinlong; Tu, Chengyue; Fu, Yimin

2018-07-01

Forest landscape restoration is emerging as an effective approach to restore degraded forests for the provision of ecosystem services and to minimize trade-offs between conservation and rural livelihoods. Policy and institutional innovations in China illustrate the governance transformation of forest landscape restoration from state-controlled to polycentric governance. Based on a case study of the Ecological Forest Purchase Program in Yong'an municipality, China's Fujian Province, this paper explores how such forest governance transformation has evolved and how it has shaped the outcomes of forest landscape restoration in terms of multi-dimensionality and actor configurations. Our analysis indicates that accommodating the participation of multiple actors and market-based instruments facilitate a smoother transition from state-centered to polycentric governance in forest landscape restoration. Governance transitions for forest landscape restoration must overcome a number of challenges including ensurance of a formal participation forum, fair participation, and a sustainable legislative and financial system to enhance long-term effectiveness.

Adaptive genetic variation mediates bottom-up and top-down control in an aquatic ecosystem

PubMed Central

Rudman, Seth M.; Rodriguez-Cabal, Mariano A.; Stier, Adrian; Sato, Takuya; Heavyside, Julian; El-Sabaawi, Rana W.; Crutsinger, Gregory M.

2015-01-01

Research in eco-evolutionary dynamics and community genetics has demonstrated that variation within a species can have strong impacts on associated communities and ecosystem processes. Yet, these studies have centred around individual focal species and at single trophic levels, ignoring the role of phenotypic variation in multiple taxa within an ecosystem. Given the ubiquitous nature of local adaptation, and thus intraspecific variation, we sought to understand how combinations of intraspecific variation in multiple species within an ecosystem impacts its ecology. Using two species that co-occur and demonstrate adaptation to their natal environments, black cottonwood (Populus trichocarpa) and three-spined stickleback (Gasterosteus aculeatus), we investigated the effects of intraspecific phenotypic variation on both top-down and bottom-up forces using a large-scale aquatic mesocosm experiment. Black cottonwood genotypes exhibit genetic variation in their productivity and consequently their leaf litter subsidies to the aquatic system, which mediates the strength of top-down effects from stickleback on prey abundances. Abundances of four common invertebrate prey species and available phosphorous, the most critically limiting nutrient in freshwater systems, are dictated by the interaction between genetic variation in cottonwood productivity and stickleback morphology. These interactive effects fit with ecological theory on the relationship between productivity and top-down control and are comparable in strength to the effects of predator addition. Our results illustrate that intraspecific variation, which can evolve rapidly, is an under-appreciated driver of community structure and ecosystem function, demonstrating that a multi-trophic perspective is essential to understanding the role of evolution in structuring ecological patterns. PMID:26203004

Adaptive genetic variation mediates bottom-up and top-down control in an aquatic ecosystem.

PubMed

Rudman, Seth M; Rodriguez-Cabal, Mariano A; Stier, Adrian; Sato, Takuya; Heavyside, Julian; El-Sabaawi, Rana W; Crutsinger, Gregory M

2015-08-07

Research in eco-evolutionary dynamics and community genetics has demonstrated that variation within a species can have strong impacts on associated communities and ecosystem processes. Yet, these studies have centred around individual focal species and at single trophic levels, ignoring the role of phenotypic variation in multiple taxa within an ecosystem. Given the ubiquitous nature of local adaptation, and thus intraspecific variation, we sought to understand how combinations of intraspecific variation in multiple species within an ecosystem impacts its ecology. Using two species that co-occur and demonstrate adaptation to their natal environments, black cottonwood (Populus trichocarpa) and three-spined stickleback (Gasterosteus aculeatus), we investigated the effects of intraspecific phenotypic variation on both top-down and bottom-up forces using a large-scale aquatic mesocosm experiment. Black cottonwood genotypes exhibit genetic variation in their productivity and consequently their leaf litter subsidies to the aquatic system, which mediates the strength of top-down effects from stickleback on prey abundances. Abundances of four common invertebrate prey species and available phosphorous, the most critically limiting nutrient in freshwater systems, are dictated by the interaction between genetic variation in cottonwood productivity and stickleback morphology. These interactive effects fit with ecological theory on the relationship between productivity and top-down control and are comparable in strength to the effects of predator addition. Our results illustrate that intraspecific variation, which can evolve rapidly, is an under-appreciated driver of community structure and ecosystem function, demonstrating that a multi-trophic perspective is essential to understanding the role of evolution in structuring ecological patterns. © 2015 The Author(s).

Intelligent and robust optimization frameworks for smart grids

NASA Astrophysics Data System (ADS)

Dhansri, Naren Reddy

A smart grid implies a cyberspace real-time distributed power control system to optimally deliver electricity based on varying consumer characteristics. Although smart grids solve many of the contemporary problems, they give rise to new control and optimization problems with the growing role of renewable energy sources such as wind or solar energy. Under highly dynamic nature of distributed power generation and the varying consumer demand and cost requirements, the total power output of the grid should be controlled such that the load demand is met by giving a higher priority to renewable energy sources. Hence, the power generated from renewable energy sources should be optimized while minimizing the generation from non renewable energy sources. This research develops a demand-based automatic generation control and optimization framework for real-time smart grid operations by integrating conventional and renewable energy sources under varying consumer demand and cost requirements. Focusing on the renewable energy sources, the intelligent and robust control frameworks optimize the power generation by tracking the consumer demand in a closed-loop control framework, yielding superior economic and ecological benefits and circumvent nonlinear model complexities and handles uncertainties for superior real-time operations. The proposed intelligent system framework optimizes the smart grid power generation for maximum economical and ecological benefits under an uncertain renewable wind energy source. The numerical results demonstrate that the proposed framework is a viable approach to integrate various energy sources for real-time smart grid implementations. The robust optimization framework results demonstrate the effectiveness of the robust controllers under bounded power plant model uncertainties and exogenous wind input excitation while maximizing economical and ecological performance objectives. Therefore, the proposed framework offers a new worst-case deterministic optimization algorithm for smart grid automatic generation control.

[Applied ecology: retrospect and prospect].

PubMed

He, Xingyuan; Zeng, Dehui

2004-10-01

Applied ecology is evolved into a principal part of modern ecology that rapidly develops. The major stimulus for the development of applied ecology roots in seeking the solutions for the problems of human populations, resources and environments. Through four decades, the science of applied ecology has been becoming a huge group of disciplines. The future for the applied ecology should concern more with human-influenced and managed ecosystems, and acknowledge humans as the components of ecosystems. Nowadays and in future, the top-priorities in applied ecology should include following fields: sustainable ecosystems and biosphere, ecosystem services and ecological design, ecological assessment of genetically modified organisms, ecology of biological invasions, epidemical ecology, ecological forecasting, ecological process and its control. The authors believe that the comprehensive and active research hotspots coupled some new traits would occur around these fields in foreseeable future.

[Effects of plant viruses on vector and non-vector herbivorous arthropods and their natural enemies: a mini review].

PubMed

He, Xiao-Chan; Xu, Hong-Xing; Zhou, Xiao-Jun; Zheng, Xu-Song; Sun, Yu-Jian; Yang, Ya-Jun; Tian, Jun-Ce; Lü, Zhong-Xian

2014-05-01

Plant viruses transmitted by arthropods, as an important biotic factor, may not only directly affect the yield and quality of host plants, and development, physiological characteristics and ecological performances of their vector arthropods, but also directly or indirectly affect the non-vector herbivorous arthropods and their natural enemies in the same ecosystem, thereby causing influences to the whole agro-ecosystem. This paper reviewed the progress on the effects of plant viruses on herbivorous arthropods, including vector and non-vector, and their natural enemies, and on their ecological mechanisms to provide a reference for optimizing the management of vector and non-vector arthropod populations and sustainable control of plant viruses in agro-ecosystem.

A recirculating stream aquarium for ecological studies.

Treesearch

Gordon H. Reeves; Fred H. Everest; Carl E. McLemore

1983-01-01

Investigations of the ecological behavior of fishes often require studies in both natural and artificial stream environments. We describe a large, recirculating stream aquarium and its controls, constructed for ecological studies at the Forestry Sciences Laboratory in Corvallis.

[Ecological benefits of planting winter rapeseed in western China].

PubMed

Wang, Xue-fang; Sun, Wan-cang; Li, Fang; Kang, Yan-li; Pu, Yuan-yuan; Liu, Hong-xia; Zeng, Chao-wu; Fan, Chong-xiu

2009-03-01

To evaluate the ecological benefits of popularizing winter rapeseed planting in western China, a wind tunnel simulation test was conducted with four kinds of farmland surface, i.e., winter rapeseed, winter wheat, wheat stubble, and bare field just after spring sowing, collected from west Gansu in April. The results showed that winter rapeseed surface had a roughness of 4.08 cm and a threshold wind velocity as high as 14 m x s(-1), being more effective in blown sand control than the other three surfaces. Under the same experimental conditions, the wind erosion modulus and sand transportation rate of winter rapeseed surface were only 4.1% and 485% of those of the bare field just after spring sowing, and the losses of soil organic matter, alkali-hydrolyzed N, available P and K, catalase, urease, alkaline phosphatase, invertase, and microbes of winter rapeseed surface due to wind erosion were only 1.4%, 5.1%, 1.6%, 2.7%, 9.7%, 3.6%, 6.3%, 6.7% and 1.5% of those of the bare field, respectively. It was suggested that popularizing winter rapeseed planting in west China could control wind erosion, retain soil water and nutrients, increase multicropping index, and improve economic benefits of farmland. In addition, it could benefit the regional desertification control and ecological environment improvement.

Ecological and socioeconomic effects of China's policies for ecosystem services.

PubMed

Liu, Jianguo; Li, Shuxin; Ouyang, Zhiyun; Tam, Christine; Chen, Xiaodong

2008-07-15

To address devastating environmental crises and to improve human well-being, China has been implementing a number of national policies on payments for ecosystem services. Two of them, the Natural Forest Conservation Program (NFCP) and the Grain to Green Program (GTGP), are among the biggest programs in the world because of their ambitious goals, massive scales, huge payments, and potentially enormous impacts. The NFCP conserves natural forests through logging bans and afforestation with incentives to forest enterprises, whereas the GTGP converts cropland on steep slopes to forest and grassland by providing farmers with grain and cash subsidies. Overall ecological effects are beneficial, and socioeconomic effects are mostly positive. Whereas there are time lags in ecological effects, socioeconomic effects are more immediate. Both the NFCP and the GTGP also have global implications because they increase vegetative cover, enhance carbon sequestration, and reduce dust to other countries by controlling soil erosion. The future impacts of these programs may be even bigger. Extended payments for the GTGP have recently been approved by the central government for up to 8 years. The NFCP is likely to follow suit and receive renewed payments. To make these programs more effective, we recommend systematic planning, diversified funding, effective compensation, integrated research, and comprehensive monitoring. Effective implementation of these programs can also provide important experiences and lessons for other ecosystem service payment programs in China and many other parts of the world.

Goal Management Training and Mindfulness Meditation improve executive functions and transfer to ecological tasks of daily life in polysubstance users enrolled in therapeutic community treatment.

PubMed

Valls-Serrano, Carlos; Caracuel, Alfonso; Verdejo-Garcia, Antonio

2016-08-01

We have previously shown that Goal Management Training+Mindfulness Meditation (GMT+MM) improves executive functions in polysubstance users enrolled in outpatient treatment. The aim of this study was to establish if GMT+MM has similar positive effects on executive functions in polysubstance users in residential treatment, and if executive functions' gains transfer to more ecologically valid goal-oriented tasks. Thirty-two polysbustance users were randomly allocated to eight weeks of GMT+MM (n=16) or control, i.e., no-intervention (n=16); both groups received treatment as usual. Outcome measures included performance in laboratory tasks of basic and complex executive functions (i.e., basic: working memory and inhibition; complex: planning and self-regulation) and in an ecological task of goal-directed behavior (the Multiple Errands Test - contextualized version, MET-CV) measured post-interventions. Results showed that GMT+MM was superior to control in improving basic measures of working memory (Letter-number sequencing; F=4.516, p=0.049) and reflection impulsivity (Information Sampling Test; F=6.217, p=0.018), along with initial thinking times during planning (Zoo Map Test; F=8.143, p=0.008). In addition, GMT+MM was superior to control in improving performance in the MET-CV (task failures; F=8.485, p=0.007). Our findings demonstrate that GMT+MM increases reflective processes and the achievement of goals in daily activities, furthermore ecological test can detects changes easily than laboratory tasks. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Participatory adaptive management leads to environmental learning outcomes extending beyond the sphere of science.

PubMed

Fujitani, Marie; McFall, Andrew; Randler, Christoph; Arlinghaus, Robert

2017-06-01

Resolving uncertainties in managed social-ecological systems requires adaptive experimentation at whole-ecosystem levels. However, whether participatory adaptive management fosters ecological understanding among stakeholders beyond the sphere of science is unknown. We experimentally involved members of German angling clubs ( n = 181 in workshops, n = 2483 in total) engaged in self-governance of freshwater fisheries resources in a large-scale ecological experiment of active adaptive management of fish stocking, which constitutes a controversial management practice for biodiversity and ecosystem functioning when conducted inappropriately. The collaborative ecological experiments spanned several years and manipulated fish densities in 24 lakes with two species. In parallel, we experimentally compared changes in ecological knowledge and antecedents of proenvironmental behavior in stakeholders and managers who were members of a participatory adaptive management treatment group, with those receiving only a standard lecture, relative to placebo controls. Using a within-subjects pretest-posttest control design, changes in ecological knowledge, environmental beliefs, attitudes, norms, and behavioral intentions were evaluated. Participants in adaptive management retained more knowledge of ecological topics after a period of 8 months compared to those receiving a standard lecture, both relative to controls. Involvement in adaptive management was also the only treatment that altered personal norms and beliefs related to stocking. Critically, only the stakeholders who participated in adaptive management reduced their behavioral intentions to engage in fish stocking in the future. Adaptive management is essential for robust ecological knowledge, and we show that involving stakeholders in adaptive management experiments is a powerful tool to enhance ecological literacy and build environmental capacity to move toward sustainability.

Participatory adaptive management leads to environmental learning outcomes extending beyond the sphere of science

PubMed Central

Fujitani, Marie; McFall, Andrew; Randler, Christoph; Arlinghaus, Robert

2017-01-01

Resolving uncertainties in managed social-ecological systems requires adaptive experimentation at whole-ecosystem levels. However, whether participatory adaptive management fosters ecological understanding among stakeholders beyond the sphere of science is unknown. We experimentally involved members of German angling clubs (n = 181 in workshops, n = 2483 in total) engaged in self-governance of freshwater fisheries resources in a large-scale ecological experiment of active adaptive management of fish stocking, which constitutes a controversial management practice for biodiversity and ecosystem functioning when conducted inappropriately. The collaborative ecological experiments spanned several years and manipulated fish densities in 24 lakes with two species. In parallel, we experimentally compared changes in ecological knowledge and antecedents of proenvironmental behavior in stakeholders and managers who were members of a participatory adaptive management treatment group, with those receiving only a standard lecture, relative to placebo controls. Using a within-subjects pretest-posttest control design, changes in ecological knowledge, environmental beliefs, attitudes, norms, and behavioral intentions were evaluated. Participants in adaptive management retained more knowledge of ecological topics after a period of 8 months compared to those receiving a standard lecture, both relative to controls. Involvement in adaptive management was also the only treatment that altered personal norms and beliefs related to stocking. Critically, only the stakeholders who participated in adaptive management reduced their behavioral intentions to engage in fish stocking in the future. Adaptive management is essential for robust ecological knowledge, and we show that involving stakeholders in adaptive management experiments is a powerful tool to enhance ecological literacy and build environmental capacity to move toward sustainability. PMID:28630904

Effects of prescribed burning on vegetation and fuel loading in three east Texas state parks

Treesearch

Sandra Rideout; Brian P. Oswald

2002-01-01

This study was conducted to evaluate the initial effectiveness of prescribed burning in the ecological restoration of forests within selected parks in east Texas. Twenty-four permanent plots were installed to monitor fuel loads, overstory, sapling, seedling, shrub and herbaceous layers within burn and control units of Mission Tejas, Tyler and Village Creek state parks...

Effects of experimental long-term CO2 exposure on Daphnia magna (Straus 1820): From physiological effects to ecological consequences.

PubMed

Parra, Gema; Galotti, Andréa; Jiménez-Melero, Raquel; Guerrero, Francisco; Sánchez-Moyano, Emilio; Jiménez-Gómez, Francisco; Conradi, Mercedes

2016-08-01

The carbon capture and storage (CCS) technologies that were proposed to mitigate environmental problems arising from anthropogenic CO2 emissions, also have potential environmental risks. An eventual CCS leak might induce very low pH values in the aquatic system. Due to the lack of knowledge of long-term CO2 exposures with very low pH values, this study aims to know the effects and consequences of such a situation for zooplankton, using the Daphnia magna experimental model. A CO2 injection system was used to provide the experimental condition. A twenty-one days experiment with control and low pH treatment (pH = 7) replicates was carried out under light and temperature-controlled conditions. Survival, individual growth, RNA:DNA ratio, and neonates production were analysed during the aforementioned period. No differences on survival (except last day), individual growth and RNA:DNA ratio were observed between both control and low pH treatments. However, clear differences were detected in neonates production and, consequently, in population growth rates and secondary production. The observed differences could be related with an energy allocation strategy to ensure individual survival but would have ecological consequences affecting higher trophic levels. Copyright © 2016 Elsevier Ltd. All rights reserved.

Emerging infectious diseases in southeast Asia: regional challenges to control.

PubMed

Coker, Richard J; Hunter, Benjamin M; Rudge, James W; Liverani, Marco; Hanvoravongchai, Piya

2011-02-12

Southeast Asia is a hotspot for emerging infectious diseases, including those with pandemic potential. Emerging infectious diseases have exacted heavy public health and economic tolls. Severe acute respiratory syndrome rapidly decimated the region's tourist industry. Influenza A H5N1 has had a profound effect on the poultry industry. The reasons why southeast Asia is at risk from emerging infectious diseases are complex. The region is home to dynamic systems in which biological, social, ecological, and technological processes interconnect in ways that enable microbes to exploit new ecological niches. These processes include population growth and movement, urbanisation, changes in food production, agriculture and land use, water and sanitation, and the effect of health systems through generation of drug resistance. Southeast Asia is home to about 600 million people residing in countries as diverse as Singapore, a city state with a gross domestic product (GDP) of US$37,500 per head, and Laos, until recently an overwhelmingly rural economy, with a GDP of US$890 per head. The regional challenges in control of emerging infectious diseases are formidable and range from influencing the factors that drive disease emergence, to making surveillance systems fit for purpose, and ensuring that regional governance mechanisms work effectively to improve control interventions. Copyright © 2011 Elsevier Ltd. All rights reserved.

A malaria transmission-directed model of mosquito life cycle and ecology

PubMed Central

2011-01-01

Background Malaria is a major public health issue in much of the world, and the mosquito vectors which drive transmission are key targets for interventions. Mathematical models for planning malaria eradication benefit from detailed representations of local mosquito populations, their natural dynamics and their response to campaign pressures. Methods A new model is presented for mosquito population dynamics, effects of weather, and impacts of multiple simultaneous interventions. This model is then embedded in a large-scale individual-based simulation and results for local elimination of malaria are discussed. Mosquito population behaviours, such as anthropophily and indoor feeding, are included to study their effect upon the efficacy of vector control-based elimination campaigns. Results Results for vector control tools, such as bed nets, indoor spraying, larval control and space spraying, both alone and in combination, are displayed for a single-location simulation with vector species and seasonality characteristic of central Tanzania, varying baseline transmission intensity and vector bionomics. The sensitivities to habitat type, anthropophily, indoor feeding, and baseline transmission intensity are explored. Conclusions The ability to model a spectrum of local vector species with different ecologies and behaviours allows local customization of packages of interventions and exploration of the effect of proposed new tools. PMID:21999664

Mitigating Harmful Cyanobacterial Blooms in a Human- and Climatically-Impacted World

PubMed Central

Paerl, Hans W.

2014-01-01

Bloom-forming harmful cyanobacteria (CyanoHABs) are harmful from environmental, ecological and human health perspectives by outcompeting beneficial phytoplankton, creating low oxygen conditions (hypoxia, anoxia), and by producing cyanotoxins. Cyanobacterial genera exhibit optimal growth rates and bloom potentials at relatively high water temperatures; hence, global warming plays a key role in their expansion and persistence. CyanoHABs are regulated by synergistic effects of nutrient (nitrogen:N and phosphorus:P) supplies, light, temperature, vertical stratification, water residence times, and biotic interactions. In most instances, nutrient control strategies should focus on reducing both N and P inputs. Strategies based on physical, chemical (nutrient) and biological manipulations can be effective in reducing CyanoHABs; however, these strategies are largely confined to relatively small systems, and some are prone to ecological and environmental drawbacks, including enhancing release of cyanotoxins, disruption of planktonic and benthic communities and fisheries habitat. All strategies should consider and be adaptive to climatic variability and change in order to be effective for long-term control of CyanoHABs. Rising temperatures and greater hydrologic variability will increase growth rates and alter critical nutrient thresholds for CyanoHAB development; thus, nutrient reductions for bloom control may need to be more aggressively pursued in response to climatic changes globally. PMID:25517134

78 FR 47259 - Approval and Promulgation of Implementation Plans; Washington: Thurston County Second 10-Year PM10

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-05

... Washington State Department of Ecology (Ecology) regulatory changes that strengthen the control measures... Standard (NAAQS) on August 7, 1987 (52 FR 29383). Ecology and ORCAA worked with the communities of Lacey... requirements imposed by the 1990 CAA Amendments, Ecology submitted a supplement to the attainment plan in...

The effects of analogy-based instruction on concept learning and retention in a non-formal coral reef ecology program

NASA Astrophysics Data System (ADS)

Brylske, Alexander Frederick

While a number of instructional models focus on the use of analogies, research into their effectiveness in enhancing comprehension and retention of scientific concepts, particularly involving adult learners, has been limited. The purpose of this study was to determine the efficacy of using the common teaching strategy for comparing the function of a coral reef to that of a city by using an analogy-based instructional model termed FAR. The training program entitled "Marine Resource Management for Dive Professionals" (MRMDP) was developed for this study. It was targeted to professionals in the recreational scuba industry to improve their understanding of coal reef ecology, as well as orient them to pertinent marine resource management issues, and promote environmentally-responsible attitudes and diving practices among their clients. A quasi-experimental pre-post-delayed posttest control group design was used to explore five research questions and corresponding hypotheses. A 55-item researcher-developed test of coral reef ecology was administered pre and post instruction. The delayed posttest was self-administered by the subjects three weeks after course completion. Data on seven experiential variables hypothesized as research factors were collected. Ten MRMPD courses were taught in seven nations, involving 194 subjects (85 subjects in four control courses, 109 in six treatment course). The results were analyzed using multiple regression/correlation (MRC) techniques to determine: (1) any significant relationship between pretest performance and experiential variables, (2) treatment versus control group posttest performance, and (3) treatment versus control group delayed posttest performance. Within the treatment group, learning gains and retention were determined by t-test analysis. Results indicated: (1) all research factors except one were significant predictors of pretest scores in the presence of the covariate; (2) no significant difference was found between control and treatment groups' pretest scores; (3) a significant interaction effect from a MANCOVA analysis, and resulting aptitude-treatment interaction analysis, showed group membership had a differential effect on the posttest relative to pretest scores; (4) the contribution of group membership to delayed posttest performance was significant; and (5) the treatment out-performed the control group on the posttest and delayed posttest. T-test analyses of treatment group performance showed a significant positive gain and retention.

ELF (Extremely Low Frequency) Communications System Ecological Monitoring Program: Summary of 1987 Progress

DTIC Science & Technology

1989-04-01

Development . Prenatal developmental stages are especially sensitive to environmental perturbations. At present, there is conflicting evidence of direct EM...effects on embryonic or fetal development . In addition, possible effects of the ELF system on parental behavior could also have an indirect effect on... development . The purpose of this element is to determine the incidence of abnormalities in embryonic development in tree swallows at treatment and control

Genes, communities & invasive species: understanding the ecological and evolutionary dynamics of host-pathogen interactions.

PubMed

Burdon, J J; Thrall, P H; Ericson, L

2013-08-01

Reciprocal interactions between hosts and pathogens drive ecological, epidemiological and co-evolutionary trajectories, resulting in complex patterns of diversity at population, species and community levels. Recent results confirm the importance of negative frequency-dependent rather than 'arms-race' processes in the evolution of individual host-pathogen associations. At the community level, complex relationships between species abundance and diversity dampen or alter pathogen impacts. Invasive pathogens challenge these controls reflecting the earliest stages of evolutionary associations (akin to arms-race) where disease effects may be so great that they overwhelm the host's and community's ability to respond. Viewing these different stabilization/destabilization phases as a continuum provides a valuable perspective to assessment of the role of genetics and ecology in the dynamics of both natural and invasive host-pathogen associations. Copyright © 2013 Elsevier Ltd. All rights reserved.

Application of a framework for extrapolating chemical effects across species in pathways controlled by estrogen receptor-á

EPA Science Inventory

Cross-species extrapolation of toxicity data from limited surrogate test organisms to all wildlife with potential of chemical exposure remains a key challenge in ecological risk assessment. A number of factors affect extrapolation, including the chemical exposure, pharmacokinetic...

Environmental Activities, Senior High School.

ERIC Educational Resources Information Center

Larson, Robert J.

This guide, for use at the secondary level, is designed to create future citizens who will be aware and understanding of their natural environment. Among the subjects discussed are advertising as an ecological cop-out, recycling, optimum environments, hydrophonics, pest control by means of ultrasonic vibrations, the effectiveness of Cottrell…

Fungal entomopathogens: new insights on their ecology

USDA-ARS?s Scientific Manuscript database

One important mechanism for insect pest control is the use of fungal entomopathogens. Even though these organisms have been studied for more than 100 years, their effective use in the field remains elusive. Recently, however, it has been discovered that many of these entomopathogenic fungi play addi...

TRADING ALLOWANCES FOR STORMWATER CONTROL: ACCOUNTING FOR CONTINUOUS HYDROLOGY AND OPPORTUNITY COSTS

EPA Science Inventory

Excess stormwater runoff is a serious problem in a large number of urban areas, causing flooding, water pollution, groundwater recharge deficits and ecological damage to urban streams. It has been posited that to mitigate the effects of excess stormwater runoff, policy makers cou...

Interaction between Digestive Strategy and Niche Specialization Predicts Speciation Rates across Herbivorous Mammals.

PubMed

Tran, Lucy A P

2016-04-01

Biotic and abiotic factors often are treated as mutually exclusive drivers of diversification processes. In this framework, ecological specialists are expected to have higher speciation rates than generalists if abiotic factors are the primary controls on species diversity but lower rates if biotic interactions are more important. Speciation rate is therefore predicted to positively correlate with ecological specialization in the purely abiotic model but negatively correlate in the biotic model. In this study, I show that the positive relationship between ecological specialization and speciation expected from the purely abiotic model is recovered only when a species-specific trait, digestive strategy, is modeled in the terrestrial, herbivorous mammals (Mammalia). This result suggests a more nuanced model in which the response of specialized lineages to abiotic factors is dependent on a biological trait. I also demonstrate that the effect of digestive strategy on the ecological specialization-speciation rate relationship is not due to a difference in either the degree of ecological specialization or the speciation rate between foregut- and hindgut-fermenting mammals. Together, these findings suggest that a biological trait, alongside historical abiotic events, played an important role in shaping mammal speciation at long temporal and large geographic scales.

Ecological niche of Legionella pneumophila

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fliermans, C.B.

1983-01-01

This paper discusses the ecological niches, relationships and controls of Legionella derived from environmental sources. Only as clinical cases and studies relate directly to the ecological understanding of the bacterium will they be discussed. This review seeks to separate the ecological parameters associated with Legionella that are often incorporated into the medical literature as well as to highlight specific ecological studies. A series of ecological studies demonstrates the niches of Legionella, the ecological parameters that allow the bacterium to survive, grow and to be disseminated. Relationships among given habitats are explored along with biological relationships within a given habitat.

Why we need more than just randomized controlled trials to establish the effectiveness of online social networks for health behavior change.

PubMed

Vandelanotte, Corneel; Maher, Carol A

2015-01-01

Despite their popularity and potential to promote health in large populations, the effectiveness of online social networks (e.g., Facebook) to improve health behaviors has been somewhat disappointing. Most of the research examining the effectiveness of such interventions has used randomized controlled trials (RCTs). It is asserted that the modest outcomes may be due to characteristics specific to both online social networks and RCTs. The highly controlled nature of RCTs stifles the dynamic nature of online social networks. Alternative and ecologically valid research designs that evaluate online social networks in real-life conditions are needed to advance the science in this area.

Soil Sample Report in Support of the Site 300 EWTF Ecological Risk Assessment and Permit Renewal-September 2012

DOE Office of Scientific and Technical Information (OSTI.GOV)

Terusaki, Stanley; Gallegos, Gretchen; MacQueen, Donald

2012-10-02

LLNL Site 300 has applied to renew the permits for its Explosives Waste Treatment Facility (EWTF), Explosives Waste Storage Facility (EWSF) and Building 883 Storage Facility. As a part of the permit renewal process, the Department of Toxic Substances Control (DTSC) requested LLNL to obtain soil samples in order to conduct a scoping-level ecological risk assessment pursuant to the Department of Toxic Substances Control, Guidance for Ecological Risk Assessment at Hazardous Waste Sites and Permitted Facilities, Part A: Overview, July 4, 1996. As stated in the guidance document, the scoping-level ecological risk assessment provides a framework to determine the potentialmore » interaction ecological receptors and chemicals of concern from hazardous waste treatment operations in the area of EWTF.« less

[Effects of biochar on the micro-ecology of tobacco-planting soil and physiology of flue-cured tobacco].

PubMed

Chen, Yi; Chen, Wei; Lin, Ye-chun; Cheng, Jian-zhong; Pan, Wen-jie

2015-12-01

Biochar is one of the research hotspots in the field of the agroforestry waste utilization. A field experiment was carried out to investigate the effects of different amounts of tobacco stem biochar (0, 1, 10, 50 t · hm⁻²) on soil micro-ecology and physiological properties of flue-cured tobacco. The results showed that soil water content (SWC) increased at all tobacco growth stages as the amounts of biochar applications increased. There were significant differences of SWC between the treatment of 50 t · hm⁻² and other treatments at the period of tobacco vigorous growth. As the application of biochar increased, the total soil porosity and capillary porosity increased, while soil bacteria, actinomyces, fungi amount increased firstly and then decreased. The amount of soil bacteria, actinomyces, fungi reached the maximum at the treatment of 10 t · hm⁻². Soil respiration rate (SRR) at earlier stage increased with the increase of biochar application. Compared with the control, SSR under biochar treatments increased by 7.9%-36.9%, and there were significant differences of SRR between high biochar application treatments (50 t · hm⁻² and 10 t · hm⁻²) and the control. Biochar improved leaf water potential, carotenoid and chlorophyll contents. Meanwhile, the dry mass of root, shoot and total dry mass under biochar application were higher than that of the control. These results indicated that the biochar played active roles in improving tobacco-planting soil micro-ecology and regulating physiological properties of flue-cured tobacco.

Effectiveness of mobile technologies delivering Ecological Momentary Interventions for stress and anxiety: a systematic review.

PubMed

Loo Gee, Brendan; Griffiths, Kathleen M; Gulliver, Amelia

2016-01-01

Mobile technologies may be suitable for delivering Ecological Momentary Interventions (EMI) to treat anxiety in real-time. This review aims to synthesize evidence on the effectiveness of EMI for treating anxiety conditions. Four databases and the reference lists of previous studies were searched. A total of 1949 abstracts were double screened for inclusion. Sufficient studies were available to undertake a quantitative meta-analysis on EMIs on generalized anxiety symptoms. The 15 randomized trials and randomized controlled trials examined anxiety (n = 7), stress (n = 3), anxiety and stress (n = 2), panic disorder (n = 2), and social phobia (n = 1). Eight EMIs comprised self-monitoring integrated with therapy modules, seven comprised multimedia content, and three comprised self-monitoring only. The quality of studies presented high risk of biases. Meta-analysis (n = 7) demonstrated that EMIs reduced generalized anxiety compared to control and/or comparison groups (Effect Size (ES) = 0.32, 95% CI, 0.12-0.53). Most EMIs targeting stress were reported effective relative to control as were the two EMIs targeting panic disorders. The EMI targeting social phobia was not effective. EMIs have potential in treating both anxiety and stress. However, few high-quality trials have been conducted for specific anxiety disorders. Further trials are needed to assess the value of EMI technologies for anxiety in enhancing existing treatments. This study found a small significant effect of EMI studies on reducing generalized anxiety. Studies on stress demonstrated EMI was effective compared to control, with the small number of studies on panic and social phobia demonstrating mixed results. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Sensitivity analysis as an aid in modelling and control of (poorly-defined) ecological systems. [closed ecological systems

NASA Technical Reports Server (NTRS)

Hornberger, G. M.; Rastetter, E. B.

1982-01-01

A literature review of the use of sensitivity analyses in modelling nonlinear, ill-defined systems, such as ecological interactions is presented. Discussions of previous work, and a proposed scheme for generalized sensitivity analysis applicable to ill-defined systems are included. This scheme considers classes of mathematical models, problem-defining behavior, analysis procedures (especially the use of Monte-Carlo methods), sensitivity ranking of parameters, and extension to control system design.

Composition and analysis of a model waste for a CELSS (Controlled Ecological Life Support System)

NASA Technical Reports Server (NTRS)

Wydeven, T. J.

1983-01-01

A model waste based on a modest vegetarian diet is given, including composition and elemental analysis. Its use is recommended for evaluation of candidate waste treatment processes for a Controlled Ecological Life Support System (CELSS).

Comparing meta-analysis and ecological-longitudinal analysis in time-series studies. A case study of the effects of air pollution on mortality in three Spanish cities.

PubMed

Saez, M; Figueiras, A; Ballester, F; Pérez-Hoyos, S; Ocaña, R; Tobías, A

2001-06-01

The objective of this paper is to introduce a different approach, called the ecological-longitudinal, to carrying out pooled analysis in time series ecological studies. Because it gives a larger number of data points and, hence, increases the statistical power of the analysis, this approach, unlike conventional ones, allows the complementation of aspects such as accommodation of random effect models, of lags, of interaction between pollutants and between pollutants and meteorological variables, that are hardly implemented in conventional approaches. The approach is illustrated by providing quantitative estimates of the short-term effects of air pollution on mortality in three Spanish cities, Barcelona, Valencia and Vigo, for the period 1992-1994. Because the dependent variable was a count, a Poisson generalised linear model was first specified. Several modelling issues are worth mentioning. Firstly, because the relations between mortality and explanatory variables were non-linear, cubic splines were used for covariate control, leading to a generalised additive model, GAM. Secondly, the effects of the predictors on the response were allowed to occur with some lag. Thirdly, the residual autocorrelation, because of imperfect control, was controlled for by means of an autoregressive Poisson GAM. Finally, the longitudinal design demanded the consideration of the existence of individual heterogeneity, requiring the consideration of mixed models. The estimates of the relative risks obtained from the individual analyses varied across cities, particularly those associated with sulphur dioxide. The highest relative risks corresponded to black smoke in Valencia. These estimates were higher than those obtained from the ecological-longitudinal analysis. Relative risks estimated from this latter analysis were practically identical across cities, 1.00638 (95% confidence intervals 1.0002, 1.0011) for a black smoke increase of 10 microg/m(3) and 1.00415 (95% CI 1.0001, 1.0007) for a increase of 10 microg/m(3) of sulphur dioxide. Because the statistical power is higher than in the individual analysis more interactions were statistically significant, especially those among air pollutants and meteorological variables. Air pollutant levels were related to mortality in the three cities of the study, Barcelona, Valencia and Vigo. These results were consistent with similar studies in other cities, with other multicentric studies and coherent with both, previous individual, for each city, and multicentric studies for all three cities.

Microbial stress-response physiology and its implications for ecosystem function.

PubMed

Schimel, Joshua; Balser, Teri C; Wallenstein, Matthew

2007-06-01

Microorganisms have a variety of evolutionary adaptations and physiological acclimation mechanisms that allow them to survive and remain active in the face of environmental stress. Physiological responses to stress have costs at the organismal level that can result in altered ecosystem-level C, energy, and nutrient flows. These large-scale impacts result from direct effects on active microbes' physiology and by controlling the composition of the active microbial community. We first consider some general aspects of how microbes experience environmental stresses and how they respond to them. We then discuss the impacts of two important ecosystem-level stressors, drought and freezing, on microbial physiology and community composition. Even when microbial community response to stress is limited, the physiological costs imposed on soil microbes are large enough that they may cause large shifts in the allocation and fate of C and N. For example, for microbes to synthesize the osmolytes they need to survive a single drought episode they may consume up to 5% of total annual net primary production in grassland ecosystems, while acclimating to freezing conditions switches Arctic tundra soils from immobilizing N during the growing season to mineralizing it during the winter. We suggest that more effectively integrating microbial ecology into ecosystem ecology will require a more complete integration of microbial physiological ecology, population biology, and process ecology.

Ecological Principles for Invasive Plant Management

USDA-ARS?s Scientific Manuscript database

Invasive annual grasses continue to advance at an alarming rate despite efforts of control by land managers. Ecologically-based invasive plant management (EBIPM) is a holistic framework that integrates ecosystem health assessment, knowledge of ecological processes and adaptive management into a succ...

Microbiological aspects of an in situ model to study effects of antimicrobial agents on dental plaque ecology.

PubMed

Giertsen, E; Guggenheim, B; Thurnheer, T; Gmür, R

2000-10-01

This study validates an in situ model for ecological studies of dental plaque exposed to various antimicrobial agents with different modes of action on plaque bacteria. Eleven subjects wore two acrylic appliances, each containing two bovine enamel discs, during two 1-wk test periods. Using a split-mouth crossover design, the appliances were dipped twice daily for 1 min into water (control; treatment A), fluoride (26.3 mM NaF; B), zinc acetate (20.0 mM; C), or fluoride plus zinc acetate (D). Four of the subjects used also chlorhexidine diacetate (2.2 mM; E) and chlorhexidine plus fluoride (F). At the end of each period, plaque was collected from the discs, after which the microbiota were analyzed by culture, automated quantitative immunofluorescence, and a viability fluorescence stain. As compared to control, treatments B, C, and D resulted in a significant reduction of individual taxa as detected by immunofluorescence, whereas similar bacterial viability and total bacterial numbers were observed. In contrast, chlorhexidine significantly reduced bacterial viability, total cell numbers, and the abundance of most of the enumerated taxa. We conclude that this in situ model is well suited to study effects of antimicrobial agents on dental plaque ecology. Combined with viability testing, immunofluorescence is obviously superior to culture in detecting taxa-specific shifts caused by antimicrobial agents.

Social-Ecological Controls Over Earth-System Stewardship: a Framework for Sustainability in a Rapidly Changing World

NASA Astrophysics Data System (ADS)

Chapin, F. S.; Power, M. E.; Pickett, S.; Jackson, R. B.; Carter, D.; Harden, J. W.

2010-12-01

Human actions are having large and accelerating effects on Earth’s climate, environment, and ecosystems, thereby degrading ecosystem services required by society. This unsustainable trajectory demands a dramatic change in the relationship of humans with the environment and life-support systems of the planet. Earth-system stewardship is an action-oriented framework intended to foster social-ecological sustainability of a rapidly changing world. This builds on problem-relevant research about the social-ecological interactions that drive earth-system change. These include spiraling consumption in developed nations and the broadening gap between the livelihoods of rich and poor people within and among countries. Science that contributes effectively to reversing these trends requires an ongoing dialogue between scientists and users at multiple scales, communicated with sensitivity to social and cultural norms. Such science must motivate behavioral change and deliver information that is perceived as objective, timely, and useful to problem-solving. Recent developments identify four strategies that use current understanding in an environment of inevitable uncertainty and abrupt change: (1) reducing the magnitude of, and exposure and sensitivity to, known stresses; (2) focusing on proactive policies that shape change; and (3) avoiding or escaping unsustainable social-ecological traps. All social-ecological systems are vulnerable to change but have sources of adaptive capacity and resilience that can sustain ecosystem services and human well-being. Discovering and nurturing these sources of adaptive capacity requires, and defines active ecosystem stewardship.

Derivation of predicted no-effect concentration and ecological risk for atrazine better based on reproductive fitness.

PubMed

Zheng, Lei; Zhang, Yizhang; Yan, Zhenguang; Zhang, Juan; Li, Linlin; Zhu, Yan; Zhang, Yahui; Zheng, Xin; Wu, Jiangyue; Liu, Zhengtao

2017-08-01

Atrazine (ATZ) is an herbicide most commonly used in China and other regions of the world. It is reported toxic to aquatic organisms, and frequently occurs at relatively high concentrations. Currently, ATZ has been proved to affect reproduction of aquatic species at much lower levels. So it is controversial to perform ecological risk assessment using predicted no-effect concentrations (PENCs) derived from traditional endpoints, which fail to provide adequate protection to aquatic organisms. In this study, PNECs of ATZ were derived based on six endpoints of survival, growth, behavior, biochemistry, genetics and reproduction. The PNEC derived from reproductive lesion was 0.044μg ATZ L -1 , which was obviously lower than that derived from other endpoints. In addition, a tiered ecological risk assessment was conducted in the Taizi River based on six PNECs derived from six categories of toxicity endpoints. Results of these two methods of ecological risk assessment were consistent with each other, and the risk level of ATZ to aquatic organisms reached highest as taking reproductive fitness into account. The joint probability indicated that severe ecological risk rooting in reproduction might exist 93.9% and 99.9% of surface water in the Taizi River, while 5% threshold (HC 5 ) and 1% threshold (HC 1 ) were set up to protect aquatic organisms, respectively. We hope the present work could provide valuable information to manage and control ATZ pollution. Copyright © 2017 Elsevier Inc. All rights reserved.

Physical Stress, Consumer Control, and New Theory in Ecology.

PubMed

Silliman, Brian R; He, Qiang

2018-05-22

Consumer-prey interactions form the foundation of food webs and are affected by the physical environment. Multiple foundational theories in ecology [e.g., the environmental stress model (ESM), the stress-gradient hypothesis (SGH), and ecosystem resilience theory] assume increased physical stress dampens top-down control of prey. In the large majority of empirical studies, however, physical stress either does not affect or amplifies consumer control. Additive and synergistic impacts of physical stress on consumer control appear more common, for example, for herbivory versus predation, and for warm- versus cold-blooded consumers. Predictability in how physical stress affects consumer control, however, remains largely unknown. We expand classical theories in ecology so that their assumption about physical stress-consumer control relationships can be inclusive of what primarily occurs in nature. Copyright © 2018. Published by Elsevier Ltd.

Control Scheme of River-lake System from the View of Ecological Sponge Basin aiming at Sponge City Construction

NASA Astrophysics Data System (ADS)

Ding, X.; Liu, J.; Yang, Z.

2017-12-01

China is in the rapid advance of urbanization, and is promoting the Sponge City Construction (SCC) with the characteristics of natural accumulation, natural infiltration and natural purification. The Chinese government selected 16 and 14 cities as pilot cities in 2015 and 2016 respectively to carry out SCC taking Low Impact Development (LID) as the concept. However, in 2015 and 2016, water-logging occurred in 10 cities and 9 cities respectively during the pilot cities. Therefore, relying solely on LID can not solve the problem of urban flood and waterlogging. Except for a series of LID measures during the process of SCC, corresponding control scheme of river-lake system should be established to realize water-related targets. From the view of ecological sponge basin, this study presents the general idea of SCC both in and out of the unban built-up area and the corresponding control scheme of river-lake system: for the regions outside the built-up area, the main aim of SCC is to carry out the top-level design of urban flood control and waterlogging, establish the water security system outside the city for solving the problems including flood control, water resources, water environment and water ecology; for the built-up area, the main aim of SCC is to construct different kinds of urban sponge according to local conditions and develop multi-scale drainage system responding to different intensities of rainfall taking the river-lake system as the core. Taking Fenghuang County of Hunan Province as an example for the application research, the results indicate that, after the implementation of the control scheme of river-lake system: 1) together with other SCC measures including LID, the control rate of total annual runoff in Fenghuang County is expected to be 82.9% which meets the target requirement of 80%; 2) flood control and drainage standards in Fenghuang County can be increased from the current 10-year return to 20-year return; 3) urban and rural water supply guarantee rate is expected to be 98% which meets the target requirement of 95%. Therefore, the control scheme of urban river-lake system in the county is technically feasible, and can effectively solve the problems including flood control, water resources shortage and ecological water demand in the county, thus may provide strong support and guarantee for SCC.

Genotypic variability enhances the reproducibility of an ecological study.

PubMed

Milcu, Alexandru; Puga-Freitas, Ruben; Ellison, Aaron M; Blouin, Manuel; Scheu, Stefan; Freschet, Grégoire T; Rose, Laura; Barot, Sebastien; Cesarz, Simone; Eisenhauer, Nico; Girin, Thomas; Assandri, Davide; Bonkowski, Michael; Buchmann, Nina; Butenschoen, Olaf; Devidal, Sebastien; Gleixner, Gerd; Gessler, Arthur; Gigon, Agnès; Greiner, Anna; Grignani, Carlo; Hansart, Amandine; Kayler, Zachary; Lange, Markus; Lata, Jean-Christophe; Le Galliard, Jean-François; Lukac, Martin; Mannerheim, Neringa; Müller, Marina E H; Pando, Anne; Rotter, Paula; Scherer-Lorenzen, Michael; Seyhun, Rahme; Urban-Mead, Katherine; Weigelt, Alexandra; Zavattaro, Laura; Roy, Jacques

2018-02-01

Many scientific disciplines are currently experiencing a 'reproducibility crisis' because numerous scientific findings cannot be repeated consistently. A novel but controversial hypothesis postulates that stringent levels of environmental and biotic standardization in experimental studies reduce reproducibility by amplifying the impacts of laboratory-specific environmental factors not accounted for in study designs. A corollary to this hypothesis is that a deliberate introduction of controlled systematic variability (CSV) in experimental designs may lead to increased reproducibility. To test this hypothesis, we had 14 European laboratories run a simple microcosm experiment using grass (Brachypodium distachyon L.) monocultures and grass and legume (Medicago truncatula Gaertn.) mixtures. Each laboratory introduced environmental and genotypic CSV within and among replicated microcosms established in either growth chambers (with stringent control of environmental conditions) or glasshouses (with more variable environmental conditions). The introduction of genotypic CSV led to 18% lower among-laboratory variability in growth chambers, indicating increased reproducibility, but had no significant effect in glasshouses where reproducibility was generally lower. Environmental CSV had little effect on reproducibility. Although there are multiple causes for the 'reproducibility crisis', deliberately including genetic variability may be a simple solution for increasing the reproducibility of ecological studies performed under stringently controlled environmental conditions.

Socio-ecological dynamics and challenges to the governance of Neglected Tropical Disease control.

PubMed

Michael, Edwin; Madon, Shirin

2017-02-06

The current global attempts to control the so-called "Neglected Tropical Diseases (NTDs)" have the potential to significantly reduce the morbidity suffered by some of the world's poorest communities. However, the governance of these control programmes is driven by a managerial rationality that assumes predictability of proposed interventions, and which thus primarily seeks to improve the cost-effectiveness of implementation by measuring performance in terms of pre-determined outputs. Here, we argue that this approach has reinforced the narrow normal-science model for controlling parasitic diseases, and in doing so fails to address the complex dynamics, uncertainty and socio-ecological context-specificity that invariably underlie parasite transmission. We suggest that a new governance approach is required that draws on a combination of non-equilibrium thinking about the operation of complex, adaptive, systems from the natural sciences and constructivist social science perspectives that view the accumulation of scientific knowledge as contingent on historical interests and norms, if more effective control approaches sufficiently sensitive to local disease contexts are to be devised, applied and managed. At the core of this approach is an emphasis on the need for a process that assists with the inclusion of diverse perspectives, social learning and deliberation, and a reflexive approach to addressing system complexity and incertitude, while balancing this flexibility with stability-focused structures. We derive and discuss a possible governance framework and outline an organizational structure that could be used to effectively deal with the complexity of accomplishing global NTD control. We also point to examples of complexity-based management structures that have been used in parasite control previously, which could serve as practical templates for developing similar governance structures to better manage global NTD control. Our results hold important wider implications for global health policy aiming to effectively control and eradicate parasitic diseases across the world.

[A landscape ecological approach for urban non-point source pollution control].

PubMed

Guo, Qinghai; Ma, Keming; Zhao, Jingzhu; Yang, Liu; Yin, Chengqing

2005-05-01

Urban non-point source pollution is a new problem appeared with the speeding development of urbanization. The particularity of urban land use and the increase of impervious surface area make urban non-point source pollution differ from agricultural non-point source pollution, and more difficult to control. Best Management Practices (BMPs) are the effective practices commonly applied in controlling urban non-point source pollution, mainly adopting local repairing practices to control the pollutants in surface runoff. Because of the close relationship between urban land use patterns and non-point source pollution, it would be rational to combine the landscape ecological planning with local BMPs to control the urban non-point source pollution, which needs, firstly, analyzing and evaluating the influence of landscape structure on water-bodies, pollution sources and pollutant removal processes to define the relationships between landscape spatial pattern and non-point source pollution and to decide the key polluted fields, and secondly, adjusting inherent landscape structures or/and joining new landscape factors to form new landscape pattern, and combining landscape planning and management through applying BMPs into planning to improve urban landscape heterogeneity and to control urban non-point source pollution.

Assessing the likely effectiveness of multispecies management for imperiled desert fishes with niche overlap analysis

USGS Publications Warehouse

Laub, P; Budy, Phaedra

2015-01-01

A critical decision in species conservation is whether to target individual species or a complex of ecologically similar species. Management of multispecies complexes is likely to be most effective when species share similar distributions, threats, and response to threats. We used niche overlap analysis to assess ecological similarity of 3 sensitive desert fish species currently managed as an ecological complex. We measured the amount of shared distribution of multiple habitat and life history parameters between each pair of species. Habitat use and multiple life history parameters, including maximum body length, spawning temperature, and longevity, differed significantly among the 3 species. The differences in habitat use and life history parameters among the species suggest they are likely to respond differently to similar threats and that most management actions will not benefit all 3 species equally. Habitat restoration, frequency of stream dewatering, non-native species control, and management efforts in tributaries versus main stem rivers are all likely to impact each of the species differently. Our results demonstrate that niche overlap analysis provides a powerful tool for assessing the likely effectiveness of multispecies versus single-species conservation plans.

Review: biosafety assessment of Bt rice and other Bt crops using spiders as example for non-target arthropods in China.

PubMed

Yang, Huilin; Peng, Yuande; Tian, Jianxiang; Wang, Juan; Hu, Jilin; Song, Qisheng; Wang, Zhi

2017-04-01

Since the birth of transgenic crops expressing Bacillus thuringiensis (Bt) toxin for pest control, the public debate regarding ecological and environmental risks as well as benefits of Bt crops has continued unabated. The impact of Bt crops, especially on non-target invertebrates, has received particular attention. In this review, we summarize and analyze evidences for non-target effects of Bt rice on spiders, major predators in rice fields. Bt rice has been genetically modified to express the Bt protein, which has been shown to be transferred and accumulate in spiders as part of their food chain. Moreover, the Bt protein exhibits unintended effects on the physiology of spiders and spreads to higher trophic levels. Spiders possess unique physiological and ecological characteristics, revealing traits of surrogate species, and are thus considered to be excellent non-target arthropod model systems for study of Bt protein impacts. Due to the complexities of Bt protein transfer and accumulation mechanisms, as well as the apparent lack of information about resulting physiological, biochemical, and ecological effects on spiders, we raise questions and provide recommendations for promising further research.

Proceedings of the western juniper ecology and management workshop.

Treesearch

Robert E. Martin; J. Edward Dealy; David L. Caraher

1977-01-01

Western juniper (Juniperus occidentalis subsp. occidentalis) is an important invader of range lands in central and eastern Oregon. Many people have asked questions about its control, effect on range productivity, and its benefits. The papers in this proceedings resulted from a conference held in Bend, Oregon, January 1977, to...

Optimization of controlled environments for hydroponic production of leaf lettuce for human life support in CELSS

NASA Technical Reports Server (NTRS)

Mitchell, C. A.; Knight, S. L.; Ford, T. L.

1986-01-01

A research project in the food production group of the Closed Ecological Life Support System (CELSS) program sought to define optimum conditions for photosynthetic productivity of a higher plant food crop. The effects of radiation and various atmospheric compositions were studied.

ECOLOGICAL IMPACT OF INTEGRATED CHEMICAL AND BIOLOGICAL AQUATIC WEED CONTROL

EPA Science Inventory

This final report presents results of a four-year study of the ecological impacts of chemical, biological, and integrated methods of aquatic weed control. Biological and water quality changes occurred as abundance of macrophytic vegetation was altered by natural factors or manage...

How-To-Do-It. A Beetle, a Bur, and the Potato: An Introduction to Ecology.

ERIC Educational Resources Information Center

Jantzen, Paul G.

1983-01-01

Describes how the interrelation of the potato beetle, the buffalo-bur, and the potato is used as an introduction to ecology. Methods of controlling the beetle and ecological principles illustrated in the interrelationship are discussed. (JN)

Transmission models and management of lymphatic filariasis elimination.

PubMed

Michael, Edwin; Gambhir, Manoj

2010-01-01

The planning and evaluation of parasitic control programmes are complicated by the many interacting population dynamic and programmatic factors that determine infection trends under different control options. A key need is quantification about the status of the parasite system state at any one given timepoint and the dynamic change brought upon that state as an intervention program proceeds. Here, we focus on the control and elimination of the vector-borne disease, lymphatic filariasis, to show how mathematical models of parasite transmission can provide a quantitative framework for aiding the design of parasite elimination and monitoring programs by their ability to support (1) conducting rational analysis and definition of endpoints for different programmatic aims or objectives, including transmission endpoints for disease elimination, (2) undertaking strategic analysis to aid the optimal design of intervention programs to meet set endpoints under different endemic settings and (3) providing support for performing informed evaluations of ongoing programs, including aiding the formation of timely adaptive management strategies to correct for any observed deficiencies in program effectiveness. The results also highlight how the use of a model-based framework will be critical to addressing the impacts of ecological complexities, heterogeneities and uncertainties on effective parasite management and thereby guiding the development of strategies to resolve and overcome such real-world complexities. In particular, we underscore how this approach can provide a link between ecological science and policy by revealing novel tools and measures to appraise and enhance the biological controllability or eradicability of parasitic diseases. We conclude by emphasizing an urgent need to develop and apply flexible adaptive management frameworks informed by mathematical models that are based on learning and reducing uncertainty using monitoring data, apply phased or sequential decision-making to address extant uncertainty and focus on developing ecologically resilient management strategies, in ongoing efforts to control or eliminate filariasis and other parasitic diseases in resource-poor communities.

TRANSLATING ECOLOGY, PHYSIOLOGY, BIOCHEMISTRY, AND POPULATION GENETICS RESEARCH TO MEET THE CHALLENGE OF TICK AND TICK-BORNE DISEASES IN NORTH AMERICA.

PubMed

Esteve-Gassent, Maria D; Castro-Arellano, Ivan; Feria-Arroyo, Teresa P; Patino, Ramiro; Li, Andrew Y; Medina, Raul F; de León, Adalberto A Pérez; Rodríguez-Vivas, Roger Iván

2016-05-01

Emerging and re-emerging tick-borne diseases threaten public health and the wellbeing of domestic animals and wildlife globally. The adoption of an evolutionary ecology framework aimed to diminish the impact of tick-borne diseases needs to be part of strategies to protect human and animal populations. We present a review of current knowledge on the adaptation of ticks to their environment, and the impact that global change could have on their geographic distribution in North America. Environmental pressures will affect tick population genetics by selecting genotypes able to withstand new and changing environments and by altering the connectivity and isolation of several tick populations. Research in these areas is particularly lacking in the southern United States and most of Mexico with knowledge gaps on the ecology of these diseases, including a void in the identity of reservoir hosts for several tick-borne pathogens. Additionally, the way in which anthropogenic changes to landscapes may influence tick-borne disease ecology remains to be fully understood. Enhanced knowledge in these areas is needed in order to implement effective and sustainable integrated tick management strategies. We propose to refocus ecology studies with emphasis on metacommunity-based approaches to enable a holistic perspective addressing whole pathogen and host assemblages. Network analyses could be used to develop mechanistic models involving multihost-pathogen communities. An increase in our understanding of the ecology of tick-borne diseases across their geographic distribution will aid in the design of effective area-wide tick control strategies aimed to diminish the burden of pathogens transmitted by ticks. © 2016 Wiley Periodicals, Inc.

[Assessment on the ecological suitability in Zhuhai City, Guangdong, China, based on minimum cumulative resistance model].

PubMed

Li, Jian-fei; Li, Lin; Guo, Luo; Du, Shi-hong

2016-01-01

Urban landscape has the characteristics of spatial heterogeneity. Because the expansion process of urban constructive or ecological land has different resistance values, the land unit stimulates and promotes the expansion of ecological land with different intensity. To compare the effect of promoting and hindering functions in the same land unit, we firstly compared the minimum cumulative resistance value of promoting and hindering functions, and then looked for the balance of two landscape processes under the same standard. According to the ecology principle of minimum limit factor, taking the minimum cumulative resistance analysis method under two expansion processes as the evaluation method of urban land ecological suitability, this research took Zhuhai City as the study area to estimate urban ecological suitability by relative evaluation method with remote sensing image, field survey, and statistics data. With the support of ArcGIS, five types of indicators on landscape types, ecological value, soil erosion sensitivity, sensitivity of geological disasters, and ecological function were selected as input parameters in the minimum cumulative resistance model to compute urban ecological suitability. The results showed that the ecological suitability of the whole Zhuhai City was divided into five levels: constructive expansion prohibited zone (10.1%), constructive expansion restricted zone (32.9%), key construction zone (36.3%), priority development zone (2.3%), and basic cropland (18.4%). Ecological suitability of the central area of Zhuhai City was divided into four levels: constructive expansion prohibited zone (11.6%), constructive expansion restricted zone (25.6%), key construction zone (52.4%), priority development zone (10.4%). Finally, we put forward the sustainable development framework of Zhuhai City according to the research conclusion. On one hand, the government should strictly control the development of the urban center area. On the other hand, the secondary urban center area such as Junchang and Doumen need improve the public infrastructure to relieve the imbalance between eastern and western development in Zhuhai City.

Controlled Ecological Life Support System: Research and Development Guidelines

NASA Technical Reports Server (NTRS)

Mason, R. M. (Editor); Carden, J. L. (Editor)

1982-01-01

Results of a workshop designed to provide a base for initiating a program of research and development of controlled ecological life support systems (CELSS) are summarized. Included are an evaluation of a ground based manned demonstration as a milestone in CELSS development, and a discussion of development requirements for a successful ground based CELSS demonstration. Research recommendations are presented concerning the following topics: nutrition and food processing, food production, waste processing, systems engineering and modelling, and ecology-systems safety.

Fish introductions and light modulate food web fluxes in tropical streams: a whole-ecosystem experimental approach.

PubMed

Collins, Sarah M; Thomas, Steven A; Heatherly, Thomas; MacNeill, Keeley L; Leduc, Antoine O H C; López-Sepulcre, Andrés; Lamphere, Bradley A; El-Sabaawi, Rana W; Reznick, David N; Pringle, Catherine M; Flecker, Alexander S

2016-11-01

Decades of ecological study have demonstrated the importance of top-down and bottom-up controls on food webs, yet few studies within this context have quantified the magnitude of energy and material fluxes at the whole-ecosystem scale. We examined top-down and bottom-up effects on food web fluxes using a field experiment that manipulated the presence of a consumer, the Trinidadian guppy Poecilia reticulata, and the production of basal resources by thinning the riparian forest canopy to increase incident light. To gauge the effects of these reach-scale manipulations on food web fluxes, we used a nitrogen ( 15 N) stable isotope tracer to compare basal resource treatments (thinned canopy vs. control) and consumer treatments (guppy introduction vs. control). The thinned canopy stream had higher primary production than the natural canopy control, leading to increased N fluxes to invertebrates that feed on benthic biofilms (grazers), fine benthic organic matter (collector-gatherers), and organic particles suspended in the water column (filter feeders). Stream reaches with guppies also had higher primary productivity and higher N fluxes to grazers and filter feeders. In contrast, N fluxes to collector-gatherers were reduced in guppy introduction reaches relative to upstream controls. N fluxes to leaf-shredding invertebrates, predatory invertebrates, and the other fish species present (Hart's killifish, Anablepsoides hartii) did not differ across light or guppy treatments, suggesting that effects on detritus-based linkages and upper trophic levels were not as strong. Effect sizes of guppy and canopy treatments on N flux rates were similar for most taxa, though guppy effects were the strongest for filter feeding invertebrates while canopy effects were the strongest for collector-gatherer invertebrates. Combined, these results extend previous knowledge about top-down and bottom-up controls on ecosystems by providing experimental, reach-scale evidence that both pathways can act simultaneously and have equally strong influence on nutrient fluxes from inorganic pools through primary consumers. © 2016 by the Ecological Society of America.

Biology, ecology and management of the invasive parthenium weed (Parthenium hysterophorus L.).

PubMed

Adkins, Steve; Shabbir, Asad

2014-07-01

Parthenium weed (Parthenium hysterophorus L.) is one of the most aggressive invasive weeds, threatening natural ecosystems and agroecosystems in over 30 countries worldwide. Parthenium weed causes losses of crops and pastures, degrading the biodiversity of natural plant communities, causing human and animal health hazards and resulting in serious economic losses to people and their interests in many countries around the globe. Several of its biological and ecological attributes contribute towards its invasiveness. Various management approaches (namely cultural, mechanical, chemical and biological control) have been used to minimise losses caused by this weed, but most of these approaches are ineffective and uneconomical and/or have limitations. Although chemical control using herbicides and biological control utilising exotic insects and pathogens have been found to contribute to the management of the weed, the weed nevertheless remains a significant problem. An integrated management approach is proposed here for the effective management of parthenium weed on a sustainable basis. © 2014 Society of Chemical Industry.

Ecological effects of ocean acidification and habitat complexity on reef-associated macroinvertebrate communities.

PubMed

Fabricius, K E; De'ath, G; Noonan, S; Uthicke, S

2014-01-22

The ecological effects of ocean acidification (OA) from rising atmospheric carbon dioxide (CO2) on benthic marine communities are largely unknown. We investigated in situ the consequences of long-term exposure to high CO2 on coral-reef-associated macroinvertebrate communities around three shallow volcanic CO2 seeps in Papua New Guinea. The densities of many groups and the number of taxa (classes and phyla) of macroinvertebrates were significantly reduced at elevated CO2 (425-1100 µatm) compared with control sites. However, sensitivities of some groups, including decapod crustaceans, ascidians and several echinoderms, contrasted with predictions of their physiological CO2 tolerances derived from laboratory experiments. High CO2 reduced the availability of structurally complex corals that are essential refugia for many reef-associated macroinvertebrates. This loss of habitat complexity was also associated with losses in many macroinvertebrate groups, especially predation-prone mobile taxa, including crustaceans and crinoids. The transition from living to dead coral as substratum and habitat further altered macroinvertebrate communities, with far more taxa losing than gaining in numbers. Our study shows that indirect ecological effects of OA (reduced habitat complexity) will complement its direct physiological effects and together with the loss of coral cover through climate change will severely affect macroinvertebrate communities in coral reefs.

Ecological effects of ocean acidification and habitat complexity on reef-associated macroinvertebrate communities

PubMed Central

Fabricius, K. E.; De'ath, G.; Noonan, S.; Uthicke, S.

2014-01-01

The ecological effects of ocean acidification (OA) from rising atmospheric carbon dioxide (CO2) on benthic marine communities are largely unknown. We investigated in situ the consequences of long-term exposure to high CO2 on coral-reef-associated macroinvertebrate communities around three shallow volcanic CO2 seeps in Papua New Guinea. The densities of many groups and the number of taxa (classes and phyla) of macroinvertebrates were significantly reduced at elevated CO2 (425–1100 µatm) compared with control sites. However, sensitivities of some groups, including decapod crustaceans, ascidians and several echinoderms, contrasted with predictions of their physiological CO2 tolerances derived from laboratory experiments. High CO2 reduced the availability of structurally complex corals that are essential refugia for many reef-associated macroinvertebrates. This loss of habitat complexity was also associated with losses in many macroinvertebrate groups, especially predation-prone mobile taxa, including crustaceans and crinoids. The transition from living to dead coral as substratum and habitat further altered macroinvertebrate communities, with far more taxa losing than gaining in numbers. Our study shows that indirect ecological effects of OA (reduced habitat complexity) will complement its direct physiological effects and together with the loss of coral cover through climate change will severely affect macroinvertebrate communities in coral reefs. PMID:24307670

Managing ecological drought and flood within a nature-based approach. Reality or illusion?

NASA Astrophysics Data System (ADS)

Halbac-Cotoara-Zamfir, Rares; Finger, David; Stolte, Jannes

2017-04-01

Water hazards events, emphasized by an improperly implemented water management, may lead to ecological degradation of ecosystems. Traditional water management has generally sought to dampen the natural variability of water flows in different types of ecosystems to attain steady and dependable water supplies for domestic and industrial uses, irrigation, navigation, and hydropower, and to moderate extreme water conditions such as floods and droughts. Ecological drought can be defined as a prolonged and widespread deficit in available water supplies — including changes in natural and managed hydrology — that create multiple stresses across ecosystems, becomes a critical concern among researchers being a phenomenon much more complex than the other types of drought and requesting a specific approach. The impact of drought on ecosystem services lead to the necessity of identifying and implementing eco-reclamation measures which can generate better ecological answers to droughts. Ecological flood is the type of flood analyzed in full consideration with ecological issues, in the analyze process being approached 4 key aspects: connectivity of water system, landscapes of river and lakes, mobility of water bodies, and safety of flood control. As a consequence, both ecological drought and ecological flood represents high challenges for ecological sustainable water management in the process of identifying structural and non-structural measures for covering human demands without causing affected ecosystems to degrade or simplify. An ecological flood and drought control system will combine both the needs of the ecosystems as well as and flood and drought control measures. The components ecosystems' natural flow regime defined by magnitude, frequency, duration and peak timing (high or low flows) interact to maintain the ecosystem productivity. This productivity can be impaired by altered flow regimes generally due to structural measures designed to control flooding. However, from an ecological perspective, floods are not disasters in the sense that human society typically views them. Considering all previous aspects, it is clear that events like floods and droughts can't be avoided, but the hydrological extremes related to these events can be sustainable managed using a series of actions based on two inter-connected approaches: prevention approach and post-event management approach. The main objective remains the necessity of limiting the consequences of water hazards on socio-economic sectors but also the need of quickly and sustainable recovering after an event like this. However, the question still remains valid: Ecological flood and ecological drought can be managed through a nature-based approach? This paper will focus on a theoretical analysis of these "ecological" hydro-meteorological events and will debate a possible nature-based approach for their sustainable management.

Population ecology of feral horses in an era of fertility control management

USGS Publications Warehouse

Ransom, J.I.

2012-01-01

Management of wildlife often requires intervention to regulate growth of populations that would otherwise become overabundant. Controlling fecundity using contraceptives has become an increasingly popular tool for attempting to manage locally overabundant wildlife species, but the population-level effects of such applications are largely unknown. Contraceptive treatments can produce unexpected feedbacks that act on births, survival, immigration, and emigration. Such feedbacks may considerably influence our ability to regulate populations using fertility control. I followed feral horses (Equus caballus) in three intensively managed populations to assess longitudinal treatment effects on demography. The transient contraceptive porcine zona pellucida (PZP) produced longer duration of infertility than intended. Repeated PZP vaccinations of females extended the duration of infertility far beyond the targeted management period, with time to first post-treatment parturition increasing 411days for every annual inoculation received. When these animals did conceive and give birth, parturition was later in the year and temporally asynchronous with forage abundance. An average of 30% (range=11–77%) of females were contracepted annually during the treatment period in all three populations and apparent annual population growth rate was 4–9% lower in the post-treatment years as compared to pretreatment years. Population growth was positive, however, and increased steadily every year that a management removal did not occur. The observed number of births was 33% fewer than the expected number of births, based on number of treated females, individual efficacy of treatment, and number of untreated females and their age-specific fecundity rates. Only half of this difference was explained by the apparent residual effect of treatment. Birth rate in the youngest untreated females (age 2–5 years old) was reduced in years when their conspecifics were treated, enhancing the effects of treatment at the population-level. This was partially offset by increased survival in adults, including a 300% increase in presence of horses ≥20 years old during the post-treatment period. In closed populations of feral horses, the positive feedbacks appear to outweigh the negative feedbacks and generate a larger contraceptive effect than the sum of individual treatments. The role of fertility control is uncertain for open populations of many wildlife species, with broad consensus across a synthesis of research that negative feedbacks on fertility control performance are occurring, and in many cases increased survival and increased immigration can compensate entirely for the reduction in births attributed to treatment. Understanding species‘ life-history strategies, biology, behavioral ecology, and ecological context is critical to developing realistic expectations of regulating wildlife populations using fertility control.

Fourth report on the Oak Ridge National Laboratory Biological Monitoring and Abatement Program for White Oak Creek Watershed and the Clinch River

DOE Office of Scientific and Technical Information (OSTI.GOV)

Loar, J.M.

1994-04-01

In response to a condition of the National Pollutant Discharge Elimination System (NPDES) permit issued to Oak Ridge National Laboratory (ORNL) on April 1, 1986, a Biological Monitoring and Abatement Program (BMAP) was developed for White Oak Creek (WOC) and selected tributaries. BMAP currently consists of six major tasks that address both radiological and nonradiological contaminants in the aquatic and terrestrial environs on-site and the aquatic environs off-site. These tasks are (1) toxicity monitoring, (2) bioaccumulation monitoring of nonradiological contaminants in aquatic biota, (3) biological indicator studies, (4) instream ecological monitoring, (5) assessment of contaminants in the terrestrial environment, andmore » (6) radioecology of WOC and White Oak Lake. The ecological characterization of the WOC watershed will provide baseline data that can be used to document the ecological effects of the water pollution control program and the remedial action program. The long-term nature of BMAP ensures that the effectiveness of remedial measures will be properly evaluated.« less

Global epidemiology, ecology and control of soil-transmitted helminth infections

PubMed Central

Brooker, Simon; Clements, Archie CA; Bundy, Don AP

2007-01-01

Soil-transmitted helminth (STH) infections are among the most prevalent of chronic human infections worldwide. Based on the demonstrable impact on child development, there is a global commitment to finance and implement control strategies with a focus on school-based chemotherapy programmes. The major obstacle to the implementation of cost-effective control is the lack of accurate descriptions of the geographical distribution of infection. In recent years considerable progress has been made in the use of geographical information systems (GIS) and remote sensing (RS) to better understand helminth ecology and epidemiology, and to develop low cost ways to identify target populations for treatment. This chapter explores how this information has been used practically to guide large-scale control programmes. The use of satellite-derived environmental data has yielded new insights into the ecology of infection at a geographical scale that has proven impossible to address using more traditional approaches, and has in turn allowed spatial distributions of infection prevalence to be predicted robustly by statistical approaches. GIS/RS have increasingly been used in the context of large-scale helminth control programmes, including not only STH infections but also those focusing on schistosomiasis, filariasis and onchocerciasis. The experience indicates that GIS/RS provides a cost-effective approach to designing and monitoring programs at realistic scale. Importantly, the use of this approach has begun to transition from being a specialist approach of international vertical programs to become a routine tool in developing public sector control programs. GIS/RS is used here to describe the global distribution of STH infections and to estimate the number of infections in school age children in sub-Saharan Africa (89.9 million) and the annual cost of providing a single anthelmintic treatment using a school-based approach (US$5.0-7.6 million). These are the first estimates at a continental scale to explicitly include the fine spatial distribution of infection prevalence and population, and suggest that traditional methods have overestimated the situation. The results suggest that continent-wide control of parasites is, from a financial perspective, an attainable goal. PMID:16647972

Perspectives on ecological research at the Outdoor StreamLab, a field-scale experimental stream

NASA Astrophysics Data System (ADS)

Merten, E. C.; Dieterman, D.; Kramarczuk, K.; Lightbody, A.; Orr, C. H.; Wellnitz, T.

2009-12-01

Artificial streams hold great promise for examining ecological processes. They lend themselves to manipulations of discharge, sediment load, water chemistry, and other parameters difficult or impossible to control in natural streams. However, artificial streams also have important limitations. In this presentation we describe insights gained from several ecological studies conducted at the St. Anthony Falls Laboratory’s Outdoor StreamLab, including, 1) short-term turbidity exposure effects on fish health, 2) macroinvertebrate grazing rates on periphyton as a function of velocity, 3) rates of macroinvertebrate colonization as related to velocity, and 4) fine-scale correlations of periphytic biomass with hydraulic conditions. Several lessons emerge from these initial attempts at ecological research in the Outdoor StreamLab. We have learned that the size, flow rate, substrate, water chemistry, and available colonization population of the artificial stream limit the kinds of organisms and types of ecological processes that can be examined and the types of experiments that can be run. We suggest that short-term biotic responses are best for study in a system of this type, and note that constant experiment maintenance is essential. Operating artificial streams to meet the needs of multiple researchers also presents challenges of scheduling, coordination, and conflict resolution. Although ecological research in artificial streams has considerable potential, the planning required is no less than that of traditional field studies.

[Assessment of ecological environment benefits of reclaimed water reuse in Beijing].

PubMed

Fan, Yu-Peng; Chen, Wei-Ping

2014-10-01

With the rapid development of the social economy and the sustained growth of population, China is facing increasingly serious water problems, and reclaimed water utilization has become an effective measure to solve water shortage problem and to control further deterioration of the ecological environment. Reclaimed water utilization can not only save a lot of fresh water, but also reduce the environmental impact of wastewater discharge, and thus has great ecological environmental benefits, including resource, environmental and human health benefits and so on. This study used the opportunity cost method to construct an evaluation system for ecological environmental benefits of reclaimed water utilization, and Beijing was taken as an example to conduct an estimation of ecological environmental benefits of reclaimed water utilization. Research results indicated that the reclaimed water utilization in Beijing had considerable environmental benefits for ¥ 1.2 billion in 2010, in which replacement of fresh water accounted for the largest share. The benefits of environmental improvement and groundwater recharge were large, while the other benefits were small or negative. The ecological environment benefits of reclaimed water utilization in Beijing was about 1.8 times that of its direct economic benefits, showing that reclaimed water utilization was in accordance with sustainable development. Related methods and results will provide scientific basis to promote the development of reclaimed water utilization in our country.

Applications Research of Microbial Ecological Preparation in Sea Cucumber Culture

NASA Astrophysics Data System (ADS)

Jiang, Jiahui; Wang, Guangyu

2017-12-01

At present, micro ecological preparation is widely applied in aquaculture with good effect. The application of micro ecological preparation in sea cucumber culture can effectively improve the economic benefits. The micro ecological preparation can play the role of inhibiting harmful bacteria, purifying water quality and saving culture cost in the process of sea cucumber culture. We should select appropriate bacteria, guarantee stable environment and use with long-term in the applications of microbial ecological preparation in sea cucumber culture to obtain good effects.

A Comparative Analysis on Assessment of Land Carrying Capacity with Ecological Footprint Analysis and Index System Method

PubMed Central

Qian, Yao; Tang, Lina; Qiu, Quanyi; Xu, Tong; Liao, Jiangfu

2015-01-01

Land carrying capacity (LCC) explains whether the local land resources are effectively used to support economic activities and/or human population. LCC can be evaluated commonly with two approaches, namely ecological footprint analysis (EFA) and the index system method (ISM). EFA is helpful to investigate the effects of different land categories whereas ISM can be used to evaluate the contributions of social, environmental, and economic factors. Here we compared the two LCC-evaluation approaches with data collected from Xiamen City, a typical region where rapid economic growth and urbanization are found in China. The results show that LCC assessments with EFA and ISM not only complement each other but also are mutually supportive. Both assessments suggest that decreases in arable land and increasingly high energy consumption have major negative effects on LCC and threaten sustainable development for Xiamen City. It is important for the local policy makers, planners and designers to reduce ecological deficits by controlling fossil energy consumption, protecting arable land and forest land from converting into other land types, and slowing down the speed of urbanization, and to promote sustainability by controlling rural-to-urban immigration, increasing hazard-free treatment rate of household garbage, and raising energy consumption per unit industrial added value. Although EFA seems more appropriate for estimating LCC for a resource-output or self-sufficient region and ISM is more suitable for a resource-input region, both approaches should be employed when perform LCC assessment in any places around the world. PMID:26121142

Workers' perceptions of how jobs affect health: a social ecological perspective.

PubMed

Ettner, S L; Grzywacz, J G

2001-04-01

A national sample of 2,048 workers was asked to rate the impact of their job on their physical and mental health. Ordered logistic regression analyses based on social ecology theory showed that the workers' responses were significantly correlated with objective and subjective features of their jobs, in addition to personality characteristics. Workers who had higher levels of perceived constraints and neuroticism, worked nights or overtime, or reported serious ongoing stress at work or higher job pressure reported more negative effects. Respondents who had a higher level of extraversion, were self-employed, or worked part time or reported greater decision latitude or use of skills on the job reported more positive effects. These findings suggest that malleable features of the work environment are associated with perceived effects of work on health, even after controlling for personality traits and other sources of reporting bias.

Biology, ecology and management of Elaeagnus angustifolia L. (Russian olive) in western North America

USGS Publications Warehouse

Katz, G.L.; Shafroth, P.B.

2003-01-01

Elaeagnus angustifolia (Russian olive) is an alien tree that is increasingly common in riparian habitats of western North America. This paper reviews the pertinent scientific literature in order to determine the status of E. angustifolia as a riparian invader and to suggest ecological reasons for its success. Elaeagnus angustifolia meets the biogeographic, spread, and impact criteria for invasive species. Ecological characteristics likely enabling its invasiveness include adaptation to the physical environmental conditions that characterize semi-arid riparian habitats, lack of intense pressure from herbivores, and tolerance of the competitive effects of established vegetation. We believe that the success of this species is at least partly due to its ability to take advantage of the reduced levels of physical disturbance that characterize riparian habitats downstream from dams. Control of E. angustifolia is likely to be most promising where natural river flow regimes remain relatively intact.

Prevention and control of sexually transmitted infections among adolescents: the importance of a socio-ecological perspective--a commentary.

PubMed

DiClemente, R J; Salazar, L F; Crosby, R A; Rosenthal, S L

2005-09-01

The sexually transmitted infection (STI) epidemic among adolescents in the USA is inextricably tied to individual, psychosocial and cultural phenomena. Reconceptualizing the epidemic within an expanded socio-ecological framework may provide an opportunity to better confront its challenges. In this article, we use a socio-ecological framework to identify determinants of adolescents' sexual risk and protective behaviours as well as antecedents of their STI acquisition. The goal is to provide a synthesis of several discrete categories of research. Subsequently, we propose an integrated strategy that addresses the STI epidemic among adolescents by promoting a socio-ecological perspective in both basic research and intervention design. This approach may expand the knowledge base and facilitate the development of a broader array of intervention strategies, such as community-level interventions, policy initiatives, institutionally based programmes, and macro-level societal changes. Although there are inherent challenges associated with such an approach, the end result may have reciprocal and reinforcing effects designed to enhance the adoption and maintenance of STI-preventive practices among adolescents, and further reduce the rate of STIs.

Group size adjustment to ecological demand in a cooperative breeder.

PubMed

Zöttl, Markus; Frommen, Joachim G; Taborsky, Michael

2013-04-07

Environmental factors can determine which group size will maximize the fitness of group members. This is particularly important in cooperative breeders, where group members often serve different purposes. Experimental studies are yet lacking to check whether ecologically mediated need for help will change the propensity of dominant group members to accept immigrants. Here, we manipulated the perceived risk of predation for dominant breeders of the cooperatively breeding cichlid fish Neolamprologus pulcher to test their response to unrelated and previously unknown immigrants. Potential immigrants were more readily accepted if groups were exposed to fish predators or egg predators than to herbivorous fish or control situations lacking predation risk. Our data are consistent with both risk dilution and helping effects. Egg predators were presented before spawning, which might suggest that the fish adjust acceptance rates also to a potential future threat. Dominant group members of N. pulcher apparently consider both present and future need of help based on ecological demand. This suggests that acceptance of immigrants and, more generally, tolerance of group members on demand could be a widespread response to ecological conditions in cooperatively breeding animals.

Molecular Ecological Basis of Grasshopper (Oedaleus asiaticus) Phenotypic Plasticity under Environmental Selection

PubMed Central

Qin, Xinghu; Hao, Kun; Ma, Jingchuan; Huang, Xunbing; Tu, Xiongbing; Ali, Md. Panna; Pittendrigh, Barry R.; Cao, Guangchun; Wang, Guangjun; Nong, Xiangqun; Whitman, Douglas W.; Zhang, Zehua

2017-01-01

While ecological adaptation in insects can be reflected by plasticity of phenotype, determining the causes and molecular mechanisms for phenotypic plasticity (PP) remains a crucial and still difficult question in ecology, especially where control of insect pests is involved. Oedaleus asiaticus is one of the most dominant pests in the Inner Mongolia steppe and represents an excellent system to study phenotypic plasticity. To better understand ecological factors affecting grasshopper phenotypic plasticity and its molecular control, we conducted a full transcriptional screening of O. asiaticus grasshoppers reared in four different grassland patches in Inner Mongolia. Grasshoppers showed different degrees of PP associated with unique gene expressions and different habitat plant community compositions. Grasshopper performance variables were susceptible to habitat environment conditions and closely associated with plant architectures. Intriguingly, eco-transcriptome analysis revealed five potential candidate genes playing important roles in grasshopper performance, with gene expression closely relating to PP and plant community factors. By linking the grasshopper performances to gene profiles and ecological factors using canonical regression, we first demonstrated the eco-transcriptomic architecture (ETA) of grasshopper phenotypic traits (ETAGPTs). ETAGPTs revealed plant food type, plant density, coverage, and height were the main ecological factors influencing PP, while insect cuticle protein (ICP), negative elongation factor A (NELFA), and lactase-phlorizin hydrolase (LCT) were the key genes associated with PP. Our study gives a clear picture of gene-environment interaction in the formation and maintenance of PP and enriches our understanding of the transcriptional events underlying molecular control of rapid phenotypic plasticity associated with environmental variability. The findings of this study may also provide new targets for pest control and highlight the significance of ecological management practice on grassland conservation. PMID:29066978

Overcoming ecologic bias using the two-phase study design.

PubMed

Wakefield, Jon; Haneuse, Sebastien J-P A

2008-04-15

Ecologic (aggregate) data are widely available and widely utilized in epidemiologic studies. However, ecologic bias, which arises because aggregate data cannot characterize within-group variability in exposure and confounder variables, can only be removed by supplementing ecologic data with individual-level data. Here the authors describe the two-phase study design as a framework for achieving this objective. In phase 1, outcomes are stratified by any combination of area, confounders, and error-prone (or discretized) versions of exposures of interest. Phase 2 data, sampled within each phase 1 stratum, provide accurate measures of exposure and possibly of additional confounders. The phase 1 aggregate-level data provide a high level of statistical power and a cross-classification by which individuals may be efficiently sampled in phase 2. The phase 2 individual-level data then provide a control for ecologic bias by characterizing the within-area variability in exposures and confounders. In this paper, the authors illustrate the two-phase study design by estimating the association between infant mortality and birth weight in several regions of North Carolina for 2000-2004, controlling for gender and race. This example shows that the two-phase design removes ecologic bias and produces gains in efficiency over the use of case-control data alone. The authors discuss the advantages and disadvantages of the approach.

The maximization of the productivity of aquatic plants for use in controlled ecological life support systems (CELSS).

PubMed

Thompson, B G

1989-03-01

Lemna minor (common duckweed) and a Wolffia sp. were grown in submerged growth systems. Submerged growth increased the productivity unit volume (P/UV) of the organisms and may allow these plants to be used in a controlled ecological life support system (CELSS).

Biological control is more than just natural enemies

Treesearch

Dean E. Pearson

2005-01-01

The past decade has given rise to exciting new developments in the field of community ecology that have profound implications for biological control. The recognition that biological invasions offer unprecedented opportunities to investigate the nature of community assembly has swept invasive species studies to the forefront of popular ecology. Meanwhile,...

The maximization of the productivity of aquatic plants for use in controlled ecological life support systems (CELSS)

NASA Astrophysics Data System (ADS)

Thompson, B. G.

Lemna minor (common duckweed) and a Wolffia sp. were grown in submerged growth systems. Submerged growth increased the productivity/unit volume (P/UV) of the organisms and may allow these plants to be used in a controlled ecological life support system (CELSS).

[Challenges and countermeasures of forestry schistosomiasis control programs in ecological priority of Yangtze River economic belt development].

PubMed

Ning, Su; Yong-Jie, Xu

2016-12-13

Relevant projects carried out within the Yangtze River economic belt on the impact of schistosomiasis epidemic and transmission are important issues for "ecological priority" in the process of implementing the strategy. The key problems of schistosomiasis epidemic risk, epidemic happening repeatedly, difficulty of rehabilitating Oncomelania hupensis snail control and schistosomiasis prevention forest, lag of evaluation system and platform construction, lack of basic research, et al. were analyzed in the Yangtze River economic belt taking "ecological priority" as the basis in this paper. Then corresponding countermeasures to these challenges were put forward so as to provide the reference for the national forestry schistosomiasis control programs, which include: execution of the comprehensive prevention and control strategy, scheming of the new round of forestry schistosomiasis control programs, strengthening schistosomiasis prevention and control, promoting productivity in existing forestry to consolidate and improve the achievements of previous forestry schistosomiasis control programs, and promoting the intensity of technological innovation to improve the technological level of forestry schistosomiasis control programs.

Effect of monochloramine treatment on the microbial ecology of Legionella and associated bacterial populations in a hospital hot water system.

PubMed

Baron, Julianne L; Harris, J Kirk; Holinger, Eric P; Duda, Scott; Stevens, Mark J; Robertson, Charles E; Ross, Kimberly A; Pace, Norman R; Stout, Janet E

2015-05-01

Opportunistic pathogens, including Legionella spp. and non-tuberculous mycobacteria, can thrive in building hot water systems despite municipal and traditional on-site chlorine disinfection. Monochloramine is a relatively new approach to on-site disinfection, but the microbiological impact of on-site chloramine use has not been well studied. We hypothesized that comparison of the microbial ecology associated with monochloramine treatment versus no on-site treatment would yield highly dissimilar bacterial communities. Hot water samples were collected monthly from 7 locations for three months from two buildings in a Pennsylvania hospital complex supplied with common municipal water: (1) a hospital administrative building (no on-site treatment) and (2) an adjacent acute-care hospital treated on-site with monochloramine to control Legionella spp. Water samples were subjected to DNA extraction, rRNA PCR, and 454 pyrosequencing. Stark differences in the microbiome of the chloraminated water and the control were observed. Bacteria in the treated samples were primarily Sphingomonadales and Limnohabitans, whereas Flexibacter and Planctomycetaceae predominated in untreated control samples. Serendipitously, one sampling month coincided with dysfunction of the on-site disinfection system that resulted in a Legionella bloom detected by sequencing and culture. This study also demonstrates the potential utility of high-throughput DNA sequencing to monitor microbial ecology in water systems. Copyright © 2015 Elsevier GmbH. All rights reserved.

[Assessment of ecological environment effects of coastal development in Hebei Province, China].

PubMed

Cui, Li-Tuo; Li, Zhi-Wei

2014-07-01

Through the analysis of the development activities and the ecological environment in coastal of Hebei Province, China, an index system for evaluating the ecological environment effect, composed of 28 indices, was set up by the pressure, state and response subsystems. Using the comprehensive index evaluation method, the integrated effects of ecological environment index (EI) was calculated and its grading criterion was founded. The results showed that the ecological environment effect of Hebei Province coastal development varied from being relatively small, normal and then relatively large from 1984 to 2010, and its acceptance degree evolved from being acceptable to being unacceptable. Because the resource and environment pressures caused by coastal development were serious and a delay existed in the state relative to the response, the improvement of various measures in the response subsystem did not show a positive effect on the state, and the environmental quality of ocean showed a degrading trend. Due to the differences in coastal development pattern and strength, the ecological environment effect of development activities showed some spatial differences. The ecological environment effect of Qinhuangdao coastal development was the minimum, followed by Cangzhou and Tangshan. Cangzhou and Tangshan had reached unacceptable levels and needed to further strengthen the restoration and protection of ecological environment.

Mechanical Harvesting Effectively Controls Young Typha spp. Invasion and Unmanned Aerial Vehicle Data Enhances Post-treatment Monitoring

PubMed Central

Lishawa, Shane C.; Carson, Brendan D.; Brandt, Jodi S.; Tallant, Jason M.; Reo, Nicholas J.; Albert, Dennis A.; Monks, Andrew M.; Lautenbach, Joseph M.; Clark, Eric

2017-01-01

The ecological impacts of invasive plants increase dramatically with time since invasion. Targeting young populations for treatment is therefore an economically and ecologically effective management approach, especially when linked to post-treatment monitoring to evaluate the efficacy of management. However, collecting detailed field-based post-treatment data is prohibitively expensive, typically resulting in inadequate documentation of the ecological effects of invasive plant management. Alternative approaches, such as remote detection with unmanned aerial vehicles (UAV), provide an opportunity to advance the science and practice of restoration ecology. In this study, we sought to determine the plant community response to different mechanical removal treatments to a dominant invasive wetland macrophyte (Typha spp.) along an age-gradient within a Great Lakes coastal wetland. We assessed the post-treatment responses with both intensive field vegetation and UAV data. Prior to treatment, the oldest Typha stands had the lowest plant diversity, lowest native sedge (Carex spp.) cover, and the greatest Typha cover. Following treatment, plots that were mechanically harvested below the surface of the water differed from unharvested control and above-water harvested plots for several plant community measures, including lower Typha dominance, lower native plant cover, and greater floating and submerged aquatic species cover. Repeated-measures analysis revealed that above-water cutting increased plant diversity and aquatic species cover across all ages, and maintained native Carex spp. cover in the youngest portions of Typha stands. UAV data revealed significant post-treatment differences in normalized difference vegetation index (NDVI) scores, blue band reflectance, and vegetation height, and these remotely collected measures corresponded to field observations. Our findings suggest that both mechanically harvesting the above-water biomass of young Typha stands and harvesting older stands below-water will promote overall native community resilience, and increase the abundance of the floating and submerged aquatic plant guilds, which are the most vulnerable to invasions by large macrophytes. UAV's provided fast and spatially expansive data compared to field monitoring, and effectively measured plant community structural responses to different treatments. Study results suggest pairing UAV flights with targeted field data collection to maximize the quality of post-restoration vegetation monitoring. PMID:28487713

78 FR 14951 - State of Washington; Underground Injection Control (UIC) Program Revision

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-08

... of Ecology to the Energy Facility Site Evaluation Council to issue UIC permits at energy facilities... telephone number for the Library is (206) 553-1289. (2) Washington Department of Ecology, Water Quality... the Environmental Protection Agency, and MOUs between the Department of Ecology and the Department of...

Ecological validity of the five digit test and the oral trails test.

PubMed

Paiva, Gabrielle Chequer de Castro; Fialho, Mariana Braga; Costa, Danielle de Souza; Paula, Jonas Jardim de

2016-01-01

Tests evaluating the attentional-executive system are widely used in clinical practice. However, proximity of an objective cognitive test with real-world situations (ecological validity) is not frequently investigated. The present study evaluate the association between measures of the Five Digit Test (FDT) and the Oral Trails Test (OTT) with self-reported cognitive failures in everyday life as measured by the Cognitive Failures Questionnaire (CFQ). Brazilian adults from 18-to-65 years old voluntarily performed the FDT and OTT tests and reported the frequency of cognitive failures in their everyday life through the CFQ. After controlling for the age effect, the measures of controlled attentional processes were associated with cognitive failures, yet the cognitive flexibility of both FDT and OTT accounted for by the majority of variance in most aspects of the CFQ factors. The FDT and the OTT measures were predictive of real-world problems such as cognitive failures in everyday activities/situations.

Rewilding as nature based solution in land management

NASA Astrophysics Data System (ADS)

Novara, Agata; Gristina, Luciano; Keesstra, Saskia; Pereira, Paulo; Cerda, Artemio

2017-04-01

Rewilding is an effective tool of ecological restoration and a nature based solution for hydro-meteorological risk control. Rewilding contributes to reduce flood risk, resist droughts, helps to restore soil organic matter content, increases soil and plant biodiversity, improves the overall ecosystem and human health. The key element of rewilding is not the nature control, but following the natural processes to restore the key soil ecological factors and their connectivity. Rewilding can be applicable at different ecosystem stages, from natural reserve to more anthropogenic system such as agricultural land through the restoration of wild soil function trough permaculture or forest farming. The proposed nature based solution not only avoid the investment in traditional engineering but it also an opportunities for creating new economics model based on wild nature (ecoturism, education, wild edible plants). This work is a review of applied rewilding actions and considerations on future nature based solutions applications will be discussed .

Why are Religiousness and Spirituality Associated with Externalizing Psychopathology? A Literature Review.

PubMed

Holmes, Christopher; Kim-Spoon, Jungmeen

2016-03-01

This review explores the relation of religiousness and spirituality with externalizing psychopathology in adolescence given the heightened externalizing psychopathology during this developmental period. Utilizing a developmental psychopathology framework, previous literature is reviewed focusing on the diversity of pathways from religiousness and spirituality to externalizing psychopathology at multiple levels of analysis. Moreover, the pathways considered include both intraindividual factors (e.g., self-control, monitoring, delay discounting and time orientation, and neurobiological regulatory systems) and ecological factors (e.g., intergenerational transmission, parent-child relationships, and community relationships). These pathways are explored in light of theoretical viewpoints including social control theory, divine interaction theory, and the religious ecology model. Limitations of extant work are examined, including measurement and design issues, exploration of potential negative effects of religiousness and spirituality, and bias toward Western religions. Finally, future directions of research and clinical implications are discussed.

Why Are Religiousness and Spirituality Associated with Externalizing Psychopathology? A Literature Review

PubMed Central

Holmes, Christopher; Kim-Spoon, Jungmeen

2015-01-01

This review explores the relation of religiousness and spirituality with externalizing psychopathology in adolescence given the heightened externalizing psychopathology during this developmental period. Utilizing a developmental psychopathology framework, previous literature is reviewed focusing on the diversity of pathways from religiousness and spirituality to externalizing psychopathology at multiple levels of analysis. Moreover, the pathways considered include both intraindividual factors (e.g., self-control, monitoring, delay discounting and time orientation, and neurobiological regulatory systems) and ecological factors (e.g., intergenerational transmission, parent-child relationships, and community relationships). These pathways are explored in light of theoretical viewpoints including social control theory, divine interaction theory, and the religious ecology model. Limitations of extant work are examined, including measurement and design issues, exploration of potential negative effects of religiousness and spirituality, and bias towards Western religions. Finally, future directions of research and clinical implications are discussed. PMID:26662624

Scale-dependency of LiDAR derived terrain attributes in quantitative soil-landscape modeling: Effects of grid resolution vs. neighborhood extent

EPA Science Inventory

Quantifying the spatial distribution of soil properties is essential for ecological and environmental modeling at the landscape scale. Terrain attributes are one of the primary covariates in soil-landscape models due to their control on energy and mass fluxes, which in turn contr...

Physiological responses of lichens to factorial fumigations with nitric acid and ozone

Treesearch

J. Riddell; P.E. Padgett; T. Nash

2012-01-01

This paper addresses the effects of gaseous nitric acid (HNO3) and ozone (O3), two important air pollutants, on six lichen species with different morphological, ecological, and biological characteristics. The treatment chambers were set up in a factorial design consisting of control chambers, chambers fumigated with HNO

Competitive release as an ecological cause of stink bug outbreaks in transgenic Bt cotton in the southeast US

USDA-ARS?s Scientific Manuscript database

Insect-resistant transgenic Bt cotton has, in general, increased yield and reduced insecticide use in cotton production by successfully managing target pests. In the southeast US, Bt cotton provides effective control of Helicpverpa zea and Heliothis virescens [Lepidoptera: Noctuidae]. However Bt c...

THE ECOLOGICAL EFFECTIVENESS OF PONDS AND WETLANDS AS "BEST MANAGEMENT PRACTICES (BMPS)" FOR STREAMS IN DEVELOPING LANDSCAPES

EPA Science Inventory

Ponds and constructed wetlands, also referred to as detention/retention basins, have a long history as best management practices (BMPs) used to mitigate the impacts of stormwater runoff from developed lands on receiving waters. Initially designed for flood control by peak flow at...

Edaphic and microclimatic controls over permafrost response to fire in interior Alaska

Treesearch

D.R. Nossov; M.T. Jorgenson; K. Kielland; M. Kanevskiy

2013-01-01

Discontinuous permafrost in the North American boreal forest is strongly influenced by the effects of ecological succession on the accumulation of surface organic matter, making permafrost vulnerable to degradation resulting from fire disturbance. To assess factors affecting permafrost degradation after wildfire, we compared vegetation composition and soil properties...

Predicting fifth-grade students' understanding of ecological science concepts with motivational and cognitive variables

NASA Astrophysics Data System (ADS)

Alao, Solomon

The need to identify factors that contribute to students' understanding of ecological concepts has been widely expressed in recent literature. The purpose of this study was to investigate the relationship between fifth grade students' prior knowledge, learning strategies, interest, and learning goals and their conceptual understanding of ecological science concepts. Subject were 72 students from three fifth grade classrooms located in a metropolitan area of the eastern United States. Students completed the goal commitment, interest, and strategy use questionnaire (GISQ), and a knowledge test designed to assess their prior knowledge and conceptual understanding of ecological science concepts. The learning goals scale assessed intentions to try to learn and understand ecological concepts. The interest scale assessed the feeling and value-related valences that students ascribed to science and ecological science concepts. The strategy use scale assessed the use of two cognitive strategies (monitoring and elaboration). The knowledge test assessed students' understanding of ecological concepts (the relationship between living organisms and their environment). Scores on all measures were examined for gender differences; no significant gender differences were observed. The motivational and cognitive variables contributed to students' understanding of ecological concepts. After accounting for interest, learning goals, and strategy use, prior knowledge accounted for 28% of the total variance in conceptual understanding. After accounting for prior knowledge, interest, learning goals, and strategy use explained 7%, 6%, and 4% of the total variance in conceptual understanding, respectively. More importantly, these variables were interrelated to each other and to conceptual understanding. After controlling for prior knowledge, learning goals, and strategy use, interest did not predict the variance in conceptual understanding. After controlling for prior knowledge, interest, and strategy use, learning goals did not predict the variance in conceptual understanding. And, after controlling for prior knowledge, interest, and learning goals, strategy use did not predict the variance in conceptual understanding. Results of this study indicated that prior knowledge, interest, learning goals, and strategy use should be included in theoretical models design to explain and to predict fifth grade students' understanding of ecological concepts. Results of this study further suggested that curriculum developers and science teachers need to take fifth grade students' prior knowledge of ecological concepts, interest in science and ecological concepts; intentions to learn and understand ecological concepts, and use of cognitive strategies into account when designing instructional contexts to support these students' understanding of ecological concepts.

Qualitative variation in proanthocyanidin composition of Populus species and hybrids: genetics is the key.

PubMed

Scioneaux, Ashley N; Schmidt, Michael A; Moore, Melissa A; Lindroth, Richard L; Wooley, Stuart C; Hagerman, Ann E

2011-01-01

The literature on proanthocyanidins (tannins) in ecological systems is dominated by quantitative studies. Despite evidence that the qualitative characteristics (subunit type, polymer chain length) of these complex polyphenolics are important determinants of biological activity, little is known about genetic and environmental controls on the type of proanthocyanidins produced by plants. We tested the hypothesis that genetics, season, developmental stage, and environment determine proanthocyanidin qualitative characteristics by using four Populus "cross types" (narrowleaf [P. angustifolia], Fremont [P. fremontii], F1 hybrids, and backcrosses to narrowleaf). We used thiolysis and HPLC analysis to characterize the proanthocyanidins, and found that genetics strongly control composition. The narrowleaf plants accumulate mixed procyanidin/prodelphinidins with average composition epicatechin(11)-epigallocatechin(8)-catechin(2)-catechin((terminal)). Backcross genotypes produce mixed procyanidin/prodelphinidins similar to narrowleaf, while Fremont makes procyanidin dimers, and the F1 plants contain procyanidin heptamers. Less striking effects were noted for genotype × environment, while season and developmental zone had little effect on proanthocyanidin composition or chain length. We discuss the metabolic and ecological consequences of differences in condensed tannin qualitative traits.

Dengue Vector Dynamics (Aedes aegypti) Influenced by Climate and Social Factors in Ecuador: Implications for Targeted Control

PubMed Central

Stewart Ibarra, Anna M.; Ryan, Sadie J.; Beltrán, Efrain; Mejía, Raúl; Silva, Mercy; Muñoz, Ángel

2013-01-01

Background Dengue fever, a mosquito-borne viral disease, is now the fastest spreading tropical disease globally. Previous studies indicate that climate and human behavior interact to influence dengue virus and vector (Aedes aegypti) population dynamics; however, the relative effects of these variables depends on local ecology and social context. We investigated the roles of climate and socio-ecological factors on Ae. aegypti population dynamics in Machala, a city in southern coastal Ecuador where dengue is hyper-endemic. Methods/Principal findings We studied two proximate urban localities where we monitored weekly Ae. aegypti oviposition activity (Nov. 2010-June 2011), conducted seasonal pupal surveys, and surveyed household to identify dengue risk factors. The results of this study provide evidence that Ae. aegypti population dynamics are influenced by social risk factors that vary by season and lagged climate variables that vary by locality. Best-fit models to predict the presence of Ae. aegypti pupae included parameters for household water storage practices, access to piped water, the number of households per property, condition of the house and patio, and knowledge and perceptions of dengue. Rainfall and minimum temperature were significant predictors of oviposition activity, although the effect of rainfall varied by locality due to differences in types of water storage containers. Conclusions These results indicate the potential to reduce the burden of dengue in this region by conducting focused vector control interventions that target high-risk households and containers in each season and by developing predictive models using climate and non-climate information. These findings provide the region's public health sector with key information for conducting time and location-specific vector control campaigns, and highlight the importance of local socio-ecological studies to understand dengue dynamics. See Text S1 for an executive summary in Spanish. PMID:24324542

Life on the atoll: Singapore ecology as a neglected dimension of social order.

PubMed

Austin, Timothy

2005-10-01

Based on field interviews in Singapore in 1985, 1997, and 2003, this article addresses the issue of how island ecology helps explain the remarkable low rates of crime that are often attributed mainly to cultural and government policies. Understanding crime and control on this most densely populated Southeast Asian atoll must begin with how people are dispersed over the limited spatial area. Ecology also influences how styles of some crimes are defined and controlled. Several of Donald Black's propositions are given further consideration.

Ecological and physiological thermal niches to understand distribution of Chagas disease vectors in Latin America.

PubMed

DE LA Vega, G J; Schilman, P E

2018-03-01

In order to assess how triatomines (Hemiptera, Reduviidae), Chagas disease vectors, are distributed through Latin America, we analysed the relationship between the ecological niche and the limits of the physiological thermal niche in seven species of triatomines. We combined two methodological approaches: species distribution models, and physiological tolerances. First, we modelled the ecological niche and identified the most important abiotic factor for their distribution. Then, thermal tolerance limits were analysed by measuring maximum and minimum critical temperatures, upper lethal temperature, and 'chill-coma recovery time'. Finally, we used phylogenetic independent contrasts to analyse the link between limiting factors and the thermal tolerance range for the assessment of ecological hypotheses that provide a different outlook for the geo-epidemiology of Chagas disease. In triatomines, thermo-tolerance range increases with increasing latitude mainly due to better cold tolerances, suggesting an effect of thermal selection. In turn, physiological analyses show that species reaching southernmost areas have a higher thermo-tolerance than those with tropical distributions, denoting that thermo-tolerance is limiting the southern distribution. Understanding the latitudinal range along its physiological limits of disease vectors may prove useful to test ecological hypotheses and improve strategies and efficiency of vector control at the local and regional levels. © 2017 The Royal Entomological Society.

Effect of eco-remediation using planted floating bed system on nutrients and heavy metals in urban river water and sediment: a field study in China.

PubMed

Ning, Daliang; Huang, Yong; Pan, Ruisong; Wang, Fayuan; Wang, Hui

2014-07-01

To investigate the effect of the eco-remediation on nutrients and heavy metals in river water and sediment, a field study was carried out in a site of a 2-year eco-remediation mainly using planted floating bed system in an urban river in China. Before remediation, the tested properties of water and sediment in the will-be remediated area were not different from the control area, except higher concentrations of chemical oxygen demand (COD) and total nitrogen (TN) in the river water. After remediation, the remediation area showed effective removal of in-stream nutrients and elevation of dissolved oxygen and transparency. Compared to the control area, the remediation area had higher concentration of nitrate and lower concentrations of COD, ammonium, Mn and hexavalent Cr in the river water after a 2-year remediation. The remediation area also showed higher concentrations of organic carbon, TN, nitrate, sulfate, Fe, Cu, Pb and Zn in the sediment than in the control area. Accordingly, special attention should be paid to the ecological risk of heavy metals in sediments and plants in river eco-remediation projects especially in rivers polluted by heavy metals, although the metals were lower than the level of considerable ecological risk in this study. Copyright © 2014 Elsevier B.V. All rights reserved.

Handbook for Evaluating Ecological Effects of Pollution at DARCOM installations. Volume 4. Terrestrial Surveys

DTIC Science & Technology

1979-12-01

AD RDTE Project No. ____________ TECOM Project No. O-CO-520-EOC-004 AYL) DPG Document No. DPG HB 80-804 0 HANDBOOK FOR EVALUATING ECOLOGICAL EFFECTS...NUMBER TECOM Project No. 0-C0-520-EQC-004’__ __" . .TITLEd . .5. TYPE OF REPORT PERIOD COVERED *! Handbook for Evaluating Ecological Effects of Pollution...IS. SUPPLEMENTARY NOTES Volume 4 of seven volumes dealing with evaluating ecological effects of pollution at DARCOM installations 19. KEY WORDS

Transgenic Mosquitoes - Fact or Fiction?

PubMed

Wilke, André B B; Beier, John C; Benelli, Giovanni

2018-06-01

Technologies for controlling mosquito vectors based on genetic manipulation and the release of genetically modified mosquitoes (GMMs) are gaining ground. However, concrete epidemiological evidence of their effectiveness, sustainability, and impact on the environment and nontarget species is lacking; no reliable ecological evidence on the potential interactions among GMMs, target populations, and other mosquito species populations exists; and no GMM technology has yet been approved by the WHO Vector Control Advisory Group. Our opinion is that, although GMMs may be considered a promising control tool, more studies are needed to assess their true effectiveness, risks, and benefits. Overall, several lines of evidence must be provided before GMM-based control strategies can be used under the integrated vector management framework. Copyright © 2018 Elsevier Ltd. All rights reserved.

Environmental Statement, Lake City Station, Unit One.

DTIC Science & Technology

1973-09-17

quality, ecological effects, energy demand, entrainment, environmental effects, fish and wildlife values, Lake Erie, pollution control, social and...Creek on the northern part of the site. That portion of the site, adjacent to Lake Erie and Elk Creek, is wooded with the remaining portions being...loam to loanm, fine sand (Reference 2-1). 2-1 - - i Approximately 60 percent of the area is covered with mixed hard woods and conifers, however, the

Macroinvertebrate Taxonomic and Functional Trait Compositions within Lotic Habitats Affected By River Restoration Practices

NASA Astrophysics Data System (ADS)

White, J. C.; Hill, M. J.; Bickerton, M. A.; Wood, P. J.

2017-09-01

The widespread degradation of lotic ecosystems has prompted extensive river restoration efforts globally, but many studies have reported modest ecological responses to rehabilitation practices. The functional properties of biotic communities are rarely examined within post-project appraisals, which would provide more ecological information underpinning ecosystem responses to restoration practices and potentially pinpoint project limitations. This study examines macroinvertebrate community responses to three projects which aimed to physically restore channel morphologies. Taxonomic and functional trait compositions supported by widely occurring lotic habitats (biotopes) were examined across paired restored and non-restored (control) reaches. The multivariate location (average community composition) of taxonomic and functional trait compositions differed marginally between control and restored reaches. However, changes in the amount of multivariate dispersion were more robust and indicated greater ecological heterogeneity within restored reaches, particularly when considering functional trait compositions. Organic biotopes (macrophyte stands and macroalgae) occurred widely across all study sites and supported a high alpha (within-habitat) taxonomic diversity compared to mineralogical biotopes (sand and gravel patches), which were characteristic of restored reaches. However, mineralogical biotopes possessed a higher beta (between-habitat) functional diversity, although this was less pronounced for taxonomic compositions. This study demonstrates that examining the functional and structural properties of taxa across distinct biotopes can provide a greater understanding of biotic responses to river restoration works. Such information could be used to better understand the ecological implications of rehabilitation practices and guide more effective management strategies.

The Biological Control of the Malaria Vector

PubMed Central

Kamareddine, Layla

2012-01-01

The call for malaria control, over the last century, marked a new epoch in the history of this disease. Many control strategies targeting either the Plasmodium parasite or the Anopheles vector were shown to be effective. Yet, the emergence of drug resistant parasites and insecticide resistant mosquito strains, along with numerous health, environmental, and ecological side effects of many chemical agents, highlighted the need to develop alternative tools that either complement or substitute conventional malaria control approaches. The use of biological means is considered a fundamental part of the recently launched malaria eradication program and has so far shown promising results, although this approach is still in its infancy. This review presents an overview of the most promising biological control tools for malaria eradication, namely fungi, bacteria, larvivorous fish, parasites, viruses and nematodes. PMID:23105979

Maternal Psychological Control and Child Internalizing Symptoms: Vulnerability and Protective Factors across Bioregulatory and Ecological Domains

ERIC Educational Resources Information Center

El-Sheikh, Mona; Hinnant, J. Benjamin; Kelly, Ryan J.; Erath, Stephen

2010-01-01

Background: We examined ecological (family socioeconomic status (SES)) and bioregulatory (sleep duration, sleep efficiency) moderators of the link between maternal psychological control and children's vulnerability to internalizing symptoms. Method: A large socioeconomically diverse sample of third graders (N = 141) and their mothers participated.…

Publications of the NASA Controlled Ecological Life Support Systems (CELSS) Program 1984-86

NASA Technical Reports Server (NTRS)

1987-01-01

Publications of research sponsored by the NASA CELSS (Controlled Ecological Life Support Systems) Program are listed, along with publications of interest to the Program. The bibliography is divided into the three major divisions of CELSS research: (1) Food Production; (2) Waste Management; and (3) Systems Management and Control. This bibliography is an update of NASA CR-3911 and includes references from 1984 through 1986.

Publications of the NASA CELSS (Controlled Ecological Life Support Systems) program

NASA Technical Reports Server (NTRS)

Dufour, P. A.; Solberg, J. L.; Wallace, J. S.

1985-01-01

Publications on research sponsored by the NASA CELSS (controlled ecological life support systems) Program are listed. The bibliography is divided into four areas: (1) human requirements; (2) food production; (3) waste management; and (4) system management and control. The 210 references cover the period from the inception of the CELSS Program (1979) to the present, as well as some earlier publications during the development of the CELSS Program.

[Simulation of rainfall and snowmelt runoff reduction in a northern city based on combination of green ecological strategies.

PubMed

Han, Jin Feng; Liu, Shuo; Dai, Jun; Qiu, Hao

2018-02-01

With the aim to control and reduce rainfall and snowmelt runoff in northern cities in China, the summer runoff and spring snowmelt runoff in the studied area were simulated with the establishment of storm water management model (SWMM). According to the climate characteristics and the situation of the studied area, the low impact development (LID) green ecological strategies suitable for the studied area were established. There were three kinds of management strategies being used, including extended green roof, snow and rainwater harvesting devices, and grass-swales or trenches. We examined the impacts of those integrated green ecological measures on the summer rainfall and spring snowmelt runoff and their mitigation effects on the drainage network pressure. The results showed that the maximum flow rates of the measured rainfall in May 24th, June 10th and July 18th 2016 were 2.7, 6.2 and 7.4 m 3 ·s -1 respectively. The peak flow rates at different return periods of 1, 2, 5, 10 years were 2.39, 3.91, 6.24 and 7.85 m 3 ·s -1 , respectively. In the snowmelt period, the peak flow appeared at the beginning of March. The LID measures had positive effect on peak flow reduction, and thus delayed peak time and relieved drainage pressure. The flow reduction rate was as high as 70%. Moreover, the snow harvesting devices played a positive role in controlling snowmelt runoff in spring.

Global change, parasite transmission and disease control: lessons from ecology

PubMed Central

Boag, Brian; Ellison, Amy R.; Morgan, Eric R.; Murray, Kris; Pascoe, Emily L.; Sait, Steven M.; Booth, Mark

2017-01-01

Parasitic infections are ubiquitous in wildlife, livestock and human populations, and healthy ecosystems are often parasite rich. Yet, their negative impacts can be extreme. Understanding how both anticipated and cryptic changes in a system might affect parasite transmission at an individual, local and global level is critical for sustainable control in humans and livestock. Here we highlight and synthesize evidence regarding potential effects of ‘system changes’ (both climatic and anthropogenic) on parasite transmission from wild host–parasite systems. Such information could inform more efficient and sustainable parasite control programmes in domestic animals or humans. Many examples from diverse terrestrial and aquatic natural systems show how abiotic and biotic factors affected by system changes can interact additively, multiplicatively or antagonistically to influence parasite transmission, including through altered habitat structure, biodiversity, host demographics and evolution. Despite this, few studies of managed systems explicitly consider these higher-order interactions, or the subsequent effects of parasite evolution, which can conceal or exaggerate measured impacts of control actions. We call for a more integrated approach to investigating transmission dynamics, which recognizes these complexities and makes use of new technologies for data capture and monitoring, and to support robust predictions of altered parasite dynamics in a rapidly changing world. This article is part of the themed issue ‘Opening the black box: re-examining the ecology and evolution of parasite transmission’. PMID:28289256

Process strengths determine the forms of the relationship between plant species richness and primary productivity

PubMed Central

Wang, Zhenhong

2017-01-01

The current rates of biodiversity loss have exceeded the rates observed during the earth’s major extinction events, which spurs the studies of the ecological relationships between biodiversity and ecosystem functions, stability, and services to determine the consequences of biodiversity loss. Plant species richness-productivity relationship (SRPR) is crucial to the understanding of these relationships in plants. Most ecologists have reached a widespread consensus that the loss of plant diversity undoubtedly impairs ecosystem functions, and have proposed many processes to explain the SRPR. However, none of the available studies has satisfactorily described the forms and mechanisms clarifying the SRPR. Observed results of the SRPR forms are inconsistent, and studies have long debated the ecological processes explaining the SRPR. Here, I have developed a simple model that combines the positive and/or negative effects of sixteen ecological processes on the SRPR and models that describe the dynamics of complementary-selection effect, density effect, and the interspecific competitive stress influenced by other ecological processes. I can regulate the strengths of the effects of these ecological processes to derive the asymptotic, positive, humped, negative, and irregular forms of the SRPR, and verify these forms using the observed data. The results demonstrated that the different strengths of the ecological processes determine the forms of the SRPR. The forms of the SRPR can change with variations in the strengths of the ecological processes. The dynamic characteristics of the complementary-selection effect, density effect, and the interspecific competitive stress on the SRPR are diverse, and are dependent on the strengths and variation of the ecological processes. This report explains the diverse forms of the SRPR, clarifies the integrative effects of the different ecological processes on the SRPR, and deepens our understanding of the interactions that occur among these ecological processes. PMID:29140995

Effect of Malathion on the Microbial Ecology of Activated Sludge

DTIC Science & Technology

2015-03-26

EFFECT OF MALATHION ON THE MICROBIAL ECOLOGY OF ACTIVATED SLUDGE THESIS Seth K. Martin, Senior Master Sergeant, USAF AFIT-ENV-MS-15-M-095 DEPARTMENT...Government and is not subject to copyright protection in the United States. AFIT-ENV-MS-15-M-095 EFFECT OF MALATHION ON THE MICROBIAL ECOLOGY OF ACTIVATED...UNLIMITED. AFIT-ENV-MS-15-M-095 EFFECT OF MALATHION ON THE MICROBIAL ECOLOGY OF ACTIVATED SLUDGE THESIS Seth K. Martin, B.S. Senior Master Sergeant

Interactions between human behaviour and ecological systems.

PubMed

Milner-Gulland, E J

2012-01-19

Research on the interactions between human behaviour and ecological systems tends to focus on the direct effects of human activities on ecosystems, such as biodiversity loss. There is also increasing research effort directed towards ecosystem services. However, interventions to control people's use of the environment alter the incentives that natural resource users face, and therefore their decisions about resource use. The indirect effects of conservation interventions on biodiversity, modulated through human decision-making, are poorly studied but are likely to be significant and potentially counterintuitive. This is particularly so where people are dependent on multiple natural resources for their livelihoods, when both poverty and biodiversity loss are acute. An inter-disciplinary approach is required to quantify these interactions, with an understanding of human decision-making at its core; otherwise, predictions about the impacts of conservation policies may be highly misleading.

Interactions between human behaviour and ecological systems

PubMed Central

Milner-Gulland, E. J.

2012-01-01

Research on the interactions between human behaviour and ecological systems tends to focus on the direct effects of human activities on ecosystems, such as biodiversity loss. There is also increasing research effort directed towards ecosystem services. However, interventions to control people's use of the environment alter the incentives that natural resource users face, and therefore their decisions about resource use. The indirect effects of conservation interventions on biodiversity, modulated through human decision-making, are poorly studied but are likely to be significant and potentially counterintuitive. This is particularly so where people are dependent on multiple natural resources for their livelihoods, when both poverty and biodiversity loss are acute. An inter-disciplinary approach is required to quantify these interactions, with an understanding of human decision-making at its core; otherwise, predictions about the impacts of conservation policies may be highly misleading. PMID:22144389

40 CFR 65.14 - Addresses.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Department of Pollution Control and Ecology, 8001 National Drive, P.O. Box 9583, Little Rock, Arkansas 72209... Office Building, Richmond, Virginia 23219. (47) Washington. Department of Ecology, Olympia, Washington...

Simulation of thermal environment in a three-layer vinyl greenhouse by natural ventilation control

NASA Astrophysics Data System (ADS)

Jin, Tea-Hwan; Shin, Ki-Yeol; Yoon, Si-Won; Im, Yong-Hoon; Chang, Ki-Chang

2017-11-01

A high energy, efficient, harmonious, ecological greenhouse has been highlighted by advanced future agricultural technology recently. This greenhouse is essential for expanding the production cycle toward growth conditions through combined thermal environmental control. However, it has a negative effect on farming income via huge energy supply expenses. Because not only production income, but operating costs related to thermal load for thermal environment control is important in farming income, it needs studies such as a harmonious ecological greenhouse using natural ventilation control. This study is simulated for energy consumption and thermal environmental conditions in a three-layered greenhouse by natural ventilation using window opening. A virtual 3D model of a three-layered greenhouse was designed based on the real one in the Gangneung area. This 3D model was used to calculate a thermal environment state such as indoor temperature, relative humidity, and thermal load in the case of a window opening rate from 0 to 100%. There was also a heat exchange operated for heating or cooling controlled by various setting temperatures. The results show that the cooling load can be reduced by natural ventilation control in the summer season, and the heat exchange capacity for heating can also be simulated for growth conditions in the winter season.

Combining indoor and outdoor methods for controlling malaria vectors: an ecological model of endectocide-treated livestock and insecticidal bed nets.

PubMed

Yakob, Laith; Cameron, Mary; Lines, Jo

2017-03-13

Malaria is spread by mosquitoes that are increasingly recognised to have diverse biting behaviours. How a mosquito in a specific environment responds to differing availability of blood-host species is largely unknown and yet critical to vector control efficacy. A parsimonious mathematical model is proposed that accounts for a diverse range of host-biting behaviours and assesses their impact on combining long-lasting insecticidal nets (LLINs) with a novel approach to malaria control: livestock treated with insecticidal compounds ('endectocides') that kill biting mosquitoes. Simulations of a malaria control programme showed marked differences across biting ecologies in the efficacy of both LLINs as a stand-alone tool and the combination of LLINs with endectocide-treated cattle. During the intervals between LLIN mass campaigns, concordant use of endectocides is projected to reduce the bounce-back in malaria prevalence that can occur as LLIN efficacy decays over time, especially if replacement campaigns are delayed. Integrating these approaches can also dramatically improve the attainability of local elimination; endectocidal treatment schedules required to achieve this aim are provided for malaria vectors with different biting ecologies. Targeting blood-feeding mosquitoes by treating livestock with endectocides offers a potentially useful complement to existing malaria control programmes centred on LLIN distribution. This approach is likely to be effective against vectors with a wide range of host-preferences and biting behaviours, with the exception of species that are so strictly anthropophilic that most blood meals are taken on humans even when humans are much less available than non-human hosts. Identifying this functional relationship in wild mosquito populations and ascertaining the extent to which it differs, within as well as between species, is a critical next step before targets can be set for employing this novel approach and combination.

Bidirectional associations between binge eating and restriction in anorexia nervosa. An ecological momentary assessment study☆

PubMed Central

De Young, Kyle P.; Lavender, Jason M.; Crosby, Ross D.; Wonderlich, Stephen A.; Engel, Scott G.; Mitchell, James E.; Crow, Scott J.; Peterson, Carol B.; Le Grange, Daniel

2014-01-01

This study examined the association between restrictive eating behaviors and binge eating in anorexia nervosa (AN) using data collected in the natural environment. Women (N = 118) with DSM-IV full or sub-threshold AN reported eating disorder behaviors, including binge eating episodes, going ≥ 8 waking hours without eating, and skipping meals, during 2 weeks of ecological momentary assessment (EMA). Time-lagged generalized estimating equations tested the following hypotheses: 1) dietary restriction would predict binge eating while controlling for binge eating the previous day; 2) binge eating would predict restriction the subsequent day while controlling for restriction the previous day. After controlling for relevant covariates, the hypotheses were not supported; however, there appeared to be a cumulative effect of repeatedly going 8 consecutive hours without eating (i.e. fasting) on the risk of binge eating among individuals who recently engaged in binge eating. In addition, skipping meals was associated with a lower risk of same day binge eating. The relationship between binge eating and dietary restriction appears to be complex and may vary by type of restrictive eating behavior. Future research should aim to further clarify the nature of the interaction of binge eating and restrictive eating among individuals with AN in order to effectively eliminate these behaviors in treatment. PMID:25134738

Effects of a Teacher Professional Development Intervention on Peer Relationships in Secondary Classrooms

PubMed Central

Mikami, Amori Yee; Gregory, Anne; Allen, Joseph P.; Pianta, Robert C.; Lun, Janetta

2012-01-01

We investigated the effects of My Teaching Partner—Secondary (MTP-S), a teacher professional development intervention, on students’ peer relationships in middle and high school classrooms. MTP-S targets increasing teachers’ positive interactions with students and sensitive instructional practices and has demonstrated improvements in students’ academic achievement and motivation. The current study tested the prediction from systems theory that effects of MTP-S on students would extend beyond the academic domain—that is, the ecology of teachers’ behaviors towards students should also influence the ecology of students’ behaviors towards one another. Participants were 88 teachers (43 randomly assigned to MTP-S and 45 assigned to a control group that received the regular professional development offerings in their school) and 1423 students in their classrooms. Observations and student self-report of classroom peer interactions were collected at the start and at the end of the course. Results indicated that in MTP-S classrooms, students were observed to show improvement in positive peer interactions, although this pattern was not found in self-report data. However, moderation analyses suggested that for students with high disruptive behavior at the start of the course, teacher participation in MTP-S mitigated a typical decline towards poorer self-reported peer relationships. The relevance of findings for the social ecology of classrooms is discussed. PMID:22736890

Effects of a Teacher Professional Development Intervention on Peer Relationships in Secondary Classrooms.

PubMed

Mikami, Amori Yee; Gregory, Anne; Allen, Joseph P; Pianta, Robert C; Lun, Janetta

2011-01-01

We investigated the effects of My Teaching Partner-Secondary (MTP-S), a teacher professional development intervention, on students' peer relationships in middle and high school classrooms. MTP-S targets increasing teachers' positive interactions with students and sensitive instructional practices and has demonstrated improvements in students' academic achievement and motivation. The current study tested the prediction from systems theory that effects of MTP-S on students would extend beyond the academic domain-that is, the ecology of teachers' behaviors towards students should also influence the ecology of students' behaviors towards one another. Participants were 88 teachers (43 randomly assigned to MTP-S and 45 assigned to a control group that received the regular professional development offerings in their school) and 1423 students in their classrooms. Observations and student self-report of classroom peer interactions were collected at the start and at the end of the course. Results indicated that in MTP-S classrooms, students were observed to show improvement in positive peer interactions, although this pattern was not found in self-report data. However, moderation analyses suggested that for students with high disruptive behavior at the start of the course, teacher participation in MTP-S mitigated a typical decline towards poorer self-reported peer relationships. The relevance of findings for the social ecology of classrooms is discussed.

Potential association between the recent increase in campylobacteriosis incidence in the Netherlands and proton-pump inhibitor use - an ecological study.

PubMed

Bouwknegt, M; van Pelt, W; Kubbinga, M E; Weda, M; Havelaar, A H

2014-08-14

The Netherlands saw an unexplained increase in campylobacteriosis incidence between 2003 and 2011, following a period of continuous decrease. We conducted an ecological study and found a statistical association between campylobacteriosis incidence and the annual number of prescriptions for proton pump inhibitors (PPIs), controlling for the patient's age, fresh and frozen chicken purchases (with or without correction for campylobacter prevalence in fresh poultry meat). The effect of PPIs was larger in the young than in the elderly. However, the counterfactual population-attributable fraction for PPIs was largest for the elderly (ca 45% in 2011) and increased at population level from 8% in 2004 to 27% in 2011. Using the regression model and updated covariate values, we predicted a trend break for 2012, largely due to a decreased number of PPI prescriptions, that was subsequently confirmed by surveillance data. Although causality was not shown, the biological mechanism, age effect and trend-break prediction suggest a substantial impact of PPI use on campylobacteriosis incidence in the Netherlands. We chose the ecological study design to pilot whether it is worthwhile to further pursue the effect of PPI on campylobacteriosis and other gastrointestinal pathogens in prospective cohort studies. We now provide strong arguments to do so.

Procedures For Microbial-Ecology Laboratory

NASA Technical Reports Server (NTRS)

Huff, Timothy L.

1993-01-01

Microbial Ecology Laboratory Procedures Manual provides concise and well-defined instructions on routine technical procedures to be followed in microbiological laboratory to ensure safety, analytical control, and validity of results.

Reorganization of interaction networks modulates the persistence of species in late successional stages.

PubMed

Saavedra, Serguei; Cenci, Simone; Del-Val, Ek; Boege, Karina; Rohr, Rudolf P

2017-09-01

Ecological interaction networks constantly reorganize as interspecific interactions change across successional stages and environmental gradients. This reorganization can also be associated with the extent to which species change their preference for types of niches available in their local sites. Despite the pervasiveness of these interaction changes, previous studies have revealed that network reorganizations have a minimal or insignificant effect on global descriptors of network architecture, such as connectance, modularity and nestedness. However, little is known about whether these reorganizations may have an effect on community dynamics and composition. To answer the question above, we study the multi-year dynamics and reorganization of plant-herbivore interaction networks across secondary successional stages of a tropical dry forest. We develop new quantitative tools based on a structural stability approach to estimate the potential impact of network reorganization on species persistence. Then, we investigate whether this impact can explain the likelihood of persistence of herbivore species in the observed communities. We find that resident (early-arriving) herbivore species increase their likelihood of persistence across time and successional stages. Importantly, we demonstrate that, in late successional stages, the reorganization of interactions among resident species has a strong inhibitory effect on the likelihood of persistence of colonizing (late-arriving) herbivores. These findings support earlier predictions suggesting that, in mature communities, changes of species interactions can act as community-control mechanisms (also known as priority effects). Furthermore, our results illustrate that the dynamics and composition of ecological communities cannot be fully understood without attention to their reorganization processes, despite the invariability of global network properties. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

From innovation to application: social-ecological context, diagnostics, drugs and integrated control of schistosomiasis.

PubMed

Utzinger, Jürg; N'goran, Eliézer K; Caffrey, Conor R; Keiser, Jennifer

2011-09-01

Compared to malaria, tuberculosis and HIV/AIDS, schistosomiasis remains a truly neglected tropical disease. Schistosomiasis, perhaps more than any other disease, is entrenched in prevailing social-ecological systems, since transmission is governed by human behaviour (e.g. open defecation and patterns of unprotected surface water contacts) and ecological features (e.g. living in close proximity to suitable freshwater bodies in which intermediate host snails proliferate). Moreover, schistosomiasis is intimately linked with poverty and the disease has spread to previously non-endemic areas as a result of demographic, ecological and engineering transformations. Importantly though, thanks to increased advocacy there is growing awareness, financial and technical support to control and eventually eliminate schistosomiasis as a public health problem at local, regional and global scales. The purpose of this review is to highlight recent progress made in innovation, validation and application of new tools and strategies for research and integrated control of schistosomiasis. First, we explain that schistosomiasis is deeply embedded in social-ecological systems and explore linkages with poverty. We then summarize and challenge global statistics, risk maps and burden estimates of human schistosomiasis. Discovery and development research pertaining to novel diagnostics and drugs forms the centrepiece of our review. We discuss unresolved issues and emerging opportunities for integrated and sustainable control of schistosomiasis and conclude with a series of research needs. Copyright © 2010 Elsevier B.V. All rights reserved.

Tropical forest loss and its multitrophic effects on insect herbivory.

PubMed

Morante-Filho, José Carlos; Arroyo-Rodríguez, Víctor; Lohbeck, Madelon; Tscharntke, Teja; Faria, Deborah

2016-12-01

Forest loss threatens biodiversity, but its potential effects on multitrophic ecological interactions are poorly understood. Insect herbivory depends on complex bottom-up (e.g., resource availability and plant antiherbivore defenses) and top-down forces (e.g., abundance of predators and herbivorous), but its determinants in human-altered tropical landscapes are largely unknown. Using structural equation models, we assessed the direct and indirect effects of forest loss on insect herbivory in 40 landscapes (115 ha each) from two regions with contrasting land-use change trajectories in the Brazilian Atlantic rainforest. We considered landscape forest cover as an exogenous predictor and (1) forest structure, (2) abundance of predators (birds and arthropods), and (3) abundance of herbivorous arthropods as endogenous predictors of insect leaf damage. From 12 predicted pathways, 11 were significant and showed that (1) leaf damage increases with forest loss (direct effect); (2) leaf damage increases with forest loss through the simplification of vegetation structure and its associated dominance of herbivorous insects (indirect effect); and further demonstrate (3) a lack of top-down control of herbivores by predators (birds and arthropods). We conclude that forest loss favors insect herbivory by undermining the bottom-up control (presumably reduced plant antiherbivore defense mechanisms) in forests dominated by fast-growing pioneer plant species, and by improving the conditions required for herbivores proliferation. © 2016 by the Ecological Society of America.

Application of Guided Inquiry System Technique (GIST) to Controlled Ecological Life Support Systems (CELSS)

NASA Technical Reports Server (NTRS)

Aroeste, H.

1982-01-01

Guided Inquiry System Technique, a global approach to problem solving, was applied to the subject of Controlled Ecological Life Support Systems (CELSS). Nutrition, food processing, and the use of higher plants in a CELSS were considered by a panel of experts. Specific ideas and recommendations gleaned from discussions with panel members are presented.

Comparing meta-analysis and ecological-longitudinal analysis in time-series studies. A case study of the effects of air pollution on mortality in three Spanish cities

PubMed Central

Saez, M; Figueiras, A; Ballester, F; Perez-Hoyos, S; Ocana, R; Tobias, A

2001-01-01

STUDY OBJECTIVE—The objective of this paper is to introduce a different approach, called the ecological-longitudinal, to carrying out pooled analysis in time series ecological studies. Because it gives a larger number of data points and, hence, increases the statistical power of the analysis, this approach, unlike conventional ones, allows the complementation of aspects such as accommodation of random effect models, of lags, of interaction between pollutants and between pollutants and meteorological variables, that are hardly implemented in conventional approaches.
DESIGN—The approach is illustrated by providing quantitative estimates of the short-term effects of air pollution on mortality in three Spanish cities, Barcelona, Valencia and Vigo, for the period 1992-1994. Because the dependent variable was a count, a Poisson generalised linear model was first specified. Several modelling issues are worth mentioning. Firstly, because the relations between mortality and explanatory variables were non-linear, cubic splines were used for covariate control, leading to a generalised additive model, GAM. Secondly, the effects of the predictors on the response were allowed to occur with some lag. Thirdly, the residual autocorrelation, because of imperfect control, was controlled for by means of an autoregressive Poisson GAM. Finally, the longitudinal design demanded the consideration of the existence of individual heterogeneity, requiring the consideration of mixed models.
MAIN RESULTS—The estimates of the relative risks obtained from the individual analyses varied across cities, particularly those associated with sulphur dioxide. The highest relative risks corresponded to black smoke in Valencia. These estimates were higher than those obtained from the ecological-longitudinal analysis. Relative risks estimated from this latter analysis were practically identical across cities, 1.00638 (95% confidence intervals 1.0002, 1.0011) for a black smoke increase of 10 µg/m3 and 1.00415 (95% CI 1.0001, 1.0007) for a increase of 10 µg/m3 of sulphur dioxide. Because the statistical power is higher than in the individual analysis more interactions were statistically significant, especially those among air pollutants and meteorological variables.
CONCLUSIONS—Air pollutant levels were related to mortality in the three cities of the study, Barcelona, Valencia and Vigo. These results were consistent with similar studies in other cities, with other multicentric studies and coherent with both, previous individual, for each city, and multicentric studies for all three cities.


Keywords: air pollution; mortality; longitudinal studies PMID:11351001

Musicking as Education for Social and Ecological Peace: A New Synthesis

ERIC Educational Resources Information Center

Golden, Michael

2016-01-01

The aim of this article is twofold: first, to confirm the multi-level linkage between the ecological and social realms in terms of violence, peace, and education, and second, to explore what light ecological thinking can shed on musicking as a potentially effective tool in peace education. The effects of violence in the ecological and social…

An Investigation of the Effectiveness of Computer Simulation Programs as Tutorial Tools for Teaching Population Ecology at University.

ERIC Educational Resources Information Center

Korfiatis, K.; Papatheodorou, E.; Paraskevopoulous, S.; Stamou, G. P.

1999-01-01

Describes a study of the effectiveness of computer-simulation programs in enhancing biology students' familiarity with ecological modeling and concepts. Finds that computer simulations improved student comprehension of ecological processes expressed in mathematical form, but did not allow a full understanding of ecological concepts. Contains 28…

Short-term ecological consequences of collaborative restoration treatments in ponderosa pine forests of Colorado

USGS Publications Warehouse

Briggs, Jenny S.; Fornwalt, Paula J.; Feinstein, Jonas A.

2017-01-01

Ecological restoration treatments are being implemented at an increasing rate in ponderosa pine and other dry conifer forests across the western United States, via the USDA Forest Service’s Collaborative Forest Landscape Restoration (CFLR) program. In this program, collaborative stakeholder groups work with National Forests (NFs) to adaptively implement and monitor ecological restoration treatments intended to offset the effects of many decades of anthropogenic stressors. We initiated a novel study to expand the scope of treatment effectiveness monitoring efforts in one of the first CFLR landscapes, Colorado’s Front Range. We used a Before/After/Control/Impact framework to evaluate the short-term consequences of treatments on numerous ecological properties. We collected pre-treatment and one year post-treatment data on NF and partner agencies’ lands, in 66 plots distributed across seven treatment units and nearby untreated areas. Our results reflected progress toward several treatment objectives: treated areas had lower tree density and basal area, greater openness, no increase in exotic understory plants, no decrease in native understory plants, and no decrease in use by tree squirrels and ungulates. However, some findings suggested the need for adaptive modification of both treatment prescriptions and monitoring protocols: treatments did not promote heterogeneity of stand structure, and monitoring methods may not have been robust enough to detect changes in surface fuels. Our study highlights both the effective aspects of these restoration treatments, and the importance of initiating and continuing collaborative science-based monitoring to improve the outcomes of broad-scale forest restoration efforts.

Development of space technology for ecological habitats

NASA Technical Reports Server (NTRS)

Martello, N. V.

1986-01-01

The development of closed ecological systems for space stations is discussed. Growth chambers, control systems, microgravity, ecosystem stability, lighting equipment, and waste processing systems are among the topics discussed.

[Regional ecological construction and mission of landscape ecology].

PubMed

Xiao, Duning; Xie, Fuju; Wei, Jianbing

2004-10-01

The eco-construction on regional and landscape scale is the one which can be used to specific landscape and intercrossing ecosystem in specific region including performing scientific administration of ecosystem and optimizing environmental function. Recently, the government has taken a series of significant projects into action, such as national forest protection item, partly forest restoration, and adjustment of water, etc. Enforcing regional eco-construction and maintaining the ecology security of the nation have become the strategic requisition. In various regions, different eco-construction should be applied, for example, performing ecological safeguard measure in ecological sensitive zone, accommodating the ecological load in ecological fragile zone, etc., which can control the activities of human being, so that, sustainable development can be reached. Facing opportunity and challenge in the development of landscape ecology, we have some key topics: landscape pattern of ecological security, land use and ecological process, landscape changes under human activity stress, quantitative evaluation of the influence on human being activities, evaluation of zonal ecological security and advance warning of ecological risk, and planning and optimizing of model in landscape eco-construction.

High spectral and spatial resolution hyperspectral imagery for quantifying Russian wheat aphid infestation in wheat using the constrained energy minimization classifier

USDA-ARS?s Scientific Manuscript database

The effects of insect infestation in agricultural crops are of major ecological and economic interest because of reduced yield, increased cost of pest control, and increased risk of environmental contamination from insecticide application. The Russian wheat aphid (RWA, Diuraphis noxia) is an insect...

Soil ecological interactions: comparisons between tropical and subalpine forests

Treesearch

Grizelle Gonzalez; Ruth E. Ley; Steven K. Schmidt; Xiaoming Zou; Timothy R. Seastedt

2001-01-01

Soil fauna can influence soil processes through interactions with the microbial community. Due to the complexity of the functional roles of fauna and their effects on microbes, little consensus has been reached on the extent to which soil fauna can regulate microbial activities. We quantified soil microbial biomass and maximum growth rates in control and fauna-excluded...

Common factors drive disease and coarse woody debris dynamics in forests impacted by sudden oak death

Treesearch

Richard C. Cobb; Maggie N. Chan; Ross K. Meentemeyer; David M. Rizzo

2011-01-01

Disease ecology has made important steps in describing how epidemiological processes control the impact of pathogens on populations and communities but fewer field or theoretical studies address disease effects at the ecosystem level. We demonstrate that the same epidemiological mechanisms drive disease intensity and coarse woody debris (CWD) dynamics...

Mine reclamation in Arkansas

Treesearch

Floyd Durham; James G. Barnum

1980-01-01

Open cut mine land reclamation laws have only been effective since 1971 in Arkansas. Since that time all land affected by mining had to be reclaimed. To guarantee reclamation, the first law required a $500 per acre surety bond be posted with the Arkansas Department of Pollution Control and Ecology. The Arkansas Open Cut Land Reclamation Act of 1977 changed the bonding...

Landowner response to wildfire risk: Adaptation, mitigation or doing nothing

Treesearch

Jianbang Gan; Adam Jarrett; Cassandra Johnson Gaither

2015-01-01

Wildfire has brought about ecological, economic, and social consequences that engender human responses in many parts of the world. How to respond to wildfire risk is a common challenge across the globe particularly in areas where lands are controlled by many small private owners because effective wildfire prevention and protection require coordinated efforts of...

Supporting Families in a High-Risk Setting: Proximal Effects of the SAFEChildren Preventive Intervention

ERIC Educational Resources Information Center

Tolan, Patrick; Gorman-Smith, Deborah; Henry,David

2004-01-01

Four hundred twenty-four families who resided in inner-city neighborhoods and had a child entering 1st grade were randomly assigned to a control condition or to a family-focused preventive intervention combined with academic tutoring. SAFEChildren, which was developed from a developmental-ecological perspective, emphasizes developmental tasks and…

Relationships between adaptive and neutral genetic diversity and ecological structure and functioning: a meta-analysis

PubMed Central

Whitlock, Raj

2014-01-01

Understanding the effects of intraspecific genetic diversity on the structure and functioning of ecological communities is a fundamentally important part of evolutionary ecology and may also have conservation relevance in identifying the situations in which genetic diversity coincides with species-level diversity.Early studies within this field documented positive relationships between genetic diversity and ecological structure, but recent studies have challenged these findings. Conceptual synthesis has been hampered because studies have used different measures of intraspecific variation (phenotypically adaptive vs. neutral) and have considered different measures of ecological structure in different ecological and spatial contexts. The aim of this study is to strengthen conceptual understanding by providing an empirical synthesis quantifying the relationship between genetic diversity and ecological structure.Here, I present a meta-analysis of the relationship between genetic diversity within plant populations and the structure and functioning of associated ecological communities (including 423 effect sizes from 70 studies). I used Bayesian meta-analyses to examine (i) the strength and direction of this relationship, (ii) the extent to which phenotypically adaptive and neutral (molecular) measures of diversity differ in their association with ecological structure and (iii) variation in outcomes among different measures of ecological structure and in different ecological contexts.Effect sizes measuring the relationship between adaptive diversity (genotypic richness) and both community- and ecosystem-level ecological responses were small, but significantly positive. These associations were supported by genetic effects on species richness and productivity, respectively.There was no overall association between neutral genetic diversity and measures of ecological structure, but a positive correlation was observed under a limited set of demographic conditions. These results suggest that adaptive and neutral genetic diversity should not be treated as ecologically equivalent measures of intraspecific variation.Synthesis. This study advances the debate over whether relationships between genetic diversity and ecological structure are either simply positive or negative, by showing how the strength and direction of these relationships changes with different measures of diversity and in different ecological contexts. The results provide a solid foundation for assessing when and where an expanded synthesis between ecology and genetics will be most fruitful. PMID:25210204

Population control methods in stochastic extinction and outbreak scenarios.

PubMed

Segura, Juan; Hilker, Frank M; Franco, Daniel

2017-01-01

Adaptive limiter control (ALC) and adaptive threshold harvesting (ATH) are two related control methods that have been shown to stabilize fluctuating populations. Large variations in population abundance can threaten the constancy and the persistence stability of ecological populations, which may impede the success and efficiency of managing natural resources. Here, we consider population models that include biological mechanisms characteristic for causing extinctions on the one hand and pest outbreaks on the other hand. These models include Allee effects and the impact of natural enemies (as is typical of forest defoliating insects). We study the impacts of noise and different levels of biological parameters in three extinction and two outbreak scenarios. Our results show that ALC and ATH have an effect on extinction and outbreak risks only for sufficiently large control intensities. Moreover, there is a clear disparity between the two control methods: in the extinction scenarios, ALC can be effective and ATH can be counterproductive, whereas in the outbreak scenarios the situation is reversed, with ATH being effective and ALC being potentially counterproductive.

EPA/OFFICE OF RESEARCH AND DEVELOPMENT'S NATIONAL HEALTH AND ENVIRONMENTAL EFFECTS RESEARCH LABORATORY/WESTERN ECOLOGY DIVISION INTERNET SITE

EPA Science Inventory

The Western Ecology Division (WED) is one of four ecological effects divisions of the National Health and Environmental Effects Research Laboratory. The four divisions are distributed bio-geographically. WED's mission is 1) to provide EPA with national scientific leadership for t...

On the Likelihood of Single-Walled Carbon Nanotubes Causing Adverse Marine Ecological Effects

EPA Science Inventory

This brief article discusses the ecological effects of single-walled carbon nanotubes (SWNTs)in the marine environment. Based on new research and a review of the scientific literature, the paper concludes that SWNTs are unlikely to cause adverse ecological effects in the marine ...

Non-target organism effects tests on Vip3A and their application to the ecological risk assessment for cultivation of MIR162 maize.

PubMed

Raybould, Alan; Vlachos, Demetra

2011-06-01

Transgenic crops producing insecticidal proteins from Bacillus thuringiensis (Bt) provide economic, environmental and health benefits by maintaining or increasing crop yields with fewer applications of insecticide. To sustain these benefits, it is important to delay the evolution of insect resistance to the proteins, and to ensure that the proteins do not harm non-target organisms, particularly those that may control secondary pests that would otherwise flourish because of reduced insecticide applications. Vip3A is a Bt vegetative insecticidal protein that is active against lepidopterous pests. It has a different mode of action from other proteins for control of Lepidoptera in current Bt crops, and when combined with these proteins, it should help to delay the evolution of pest resistance to Bt crops. This paper presents data on the effects of Vip3A on non-target organisms, and an ecological risk assessment of MIR162 maize, which expresses Vip3Aa20. Laboratory studies indicate few adverse effects of Vip3A to non-target organisms: 11 of 12 species tested showed no adverse effects when exposed to high concentrations of Vip3A relative to estimated exposures resulting from cultivation of MIR162 maize. Daphnia magna exposed to Vip3Aa20 were unaffected in terms of survival or fecundity, but grew slightly more slowly than unexposed controls. The data indicate that cultivation of MIR162 maize poses negligible risk to non-target organisms, and that crops producing Vip3A are unlikely to adversely affect biological control organisms such that benefits from reduced insecticide applications are lost.

Changes in suicide rates in disaster-stricken areas following the Great East Japan Earthquake and their effect on economic factors: an ecological study.

PubMed

Orui, Masatsugu; Harada, Shuichiro; Hayashi, Mizuho

2014-11-01

Devastating disasters may increase suicide rates due to mental distress. Previous domestic studies have reported decreased suicide rates among men following disasters. Few reports are available regarding factors associated with disasters, making it difficult to discuss how these events affect suicide rates. This study aimed to observe changes in suicide rates in disaster-stricken and neighboring areas following the Great East Japan Earthquake, and examine associations between suicide rates and economic factors. Monthly suicide rates were observed from March 2009 to February 2013, during which time the earthquake occurred on March, 2011. Data were included from disaster-stricken (Iwate, Miyagi, and Fukushima Prefectures) and neighboring (control: Aomori, Akita, and Yamagata Prefectures) areas. The association between changes in suicide rates and economic variables was evaluated based on the number of bankruptcy cases and ratio of effective job offers. In disaster-stricken areas, post-disaster male suicide rates decreased during the 24 months following the earthquake. This trend differed relative to control areas. Female suicide rates increased during the first seven months. Multiple regression analysis showed that bankruptcy cases (β = 0.386, p = 0.038) and ratio of effective job offers (β = -0.445, p = 0.018) were only significantly associated with male post-disaster suicide rates in control areas. Post-disaster suicide rates differed by gender following the earthquake. Our findings suggest that considering gender differences might be important for developing future post-disaster suicide prevention measures. This ecological study revealed that increasing effective job offers and decreasing bankruptcy cases can affect protectively male suicide rates in control areas.

The conceptual imperfection of aquatic risk assessment tests: highlighting the need for tests designed to detect therapeutic effects of pharmaceutical contaminants

NASA Astrophysics Data System (ADS)

Klaminder, J.; Jonsson, M.; Fick, J.; Sundelin, A.; Brodin, T.

2014-08-01

Standardized ecotoxicological tests still constitute the fundamental tools when doing risk-assessment of aquatic contaminants. These protocols are managed towards minimal mortality in the controls, which is not representative for natural systems where mortality is often high. This methodological bias, generated from assays where mortality in the control group is systematically disregarded, makes it difficult to measure therapeutic effects of pharmaceutical contaminants leading to lower mortality. This is of concern considering that such effects on exposed organisms still may have substantial ecological consequences. In this paper, we illustrate this conceptual problem by presenting empirical data for how the therapeutic effect of Oxazepam—a common contaminant of surface waters—lower mortality rates among exposed Eurasian perch (Perca fluviatilis) from wild populations, at two different life stages. We found that fry hatched from roe that had been exposed to dilute concentrations (1.1 ± 0.3 μg l-1) of Oxazepam for 24 h 3-6 days prior to hatching showed lower mortality rates and increased activity 30 days after hatching. Similar effects, i.e. increased activity and lower mortality rates were also observed for 2-year old perch exposed to dilute Oxazepam concentrations (1.2 ± 0.4 μg l-1). We conclude that therapeutic effects from pharmaceutical contaminants need to be considered in risk assessment assays to avoid that important ecological effects from aquatic contaminants are systematically missed.

Planning riparian restoration in the context of tamarix control in Western North America

USGS Publications Warehouse

Shafroth, P.B.; Beauchamp, Vanessa B.; Briggs, M.K.; Lair, K.; Scott, M.L.; Sher, A.A.

2008-01-01

Throughout the world, the condition of many riparian ecosystems has declined due to numerous factors, including encroachment of non-native species. In the western United States, millions of dollars are spent annually to control invasions of Tamarix spp., introduced small trees or shrubs from Eurasia that have colonized bottomland ecosystems along many rivers. Resource managers seek to control Tamarix in attempts to meet various objectives, such as increasing water yield and improving wildlife habitat. Often, riparian restoration is an implicit goal, but there has been little emphasis on a process or principles to effectively plan restoration activities, and many Tamarix removal projects are unsuccessful at restoring native vegetation. We propose and summarize the key steps in a planning process aimed at developing effective restoration projects in Tamarix-dominated areas. We discuss in greater detail the biotic and abiotic factors central to the evaluation of potential restoration sites and summarize information about plant communities likely to replace Tamarix under various conditions. Although many projects begin with implementation, which includes the actual removal of Tamarix, we stress the importance of pre-project planning that includes: (1) clearly identifying project goals; (2) developing realistic project objectives based on a detailed evaluation of site conditions; (3) prioritizing and selecting Tamarix control sites with the best chance of ecological recovery; and (4) developing a detailed tactical plan before Tamarix is removed. After removal, monitoring and maintenance as part of an adaptive management approach are crucial for evaluating project success and determining the most effective methods for restoring these challenging sites. ?? 2008 Society for Ecological Restoration International.

Lyme disease ecology in a changing world: Consensus, uncertainty and critical gaps for improving control

USGS Publications Warehouse

Kilpatrick, A. Marm; Dobson, Andrew D.M.; Levi, Taal; Salkeld, Daniel J.; Swei, Andrea; Ginsberg, Howard; Kjemtrup, Anne; Padgett, Kerry A.; Jensen, Per A.; Fish, Durland; Ogden, Nick H.; Diuk-Wasser, Maria A.

2017-01-01

Lyme disease is the most common tick-borne disease in temperate regions of North America, Europe and Asia, and the number of reported cases has increased in many regions as landscapes have been altered. Although there has been extensive work on the ecology and epidemiology of this disease in both Europe and North America, substantial uncertainty exists about fundamental aspects that determine spatial and temporal variation in both disease risk and human incidence, which hamper effective and efficient prevention and control. Here we describe areas of consensus that can be built on, identify areas of uncertainty and outline research needed to fill these gaps to facilitate predictive models of disease risk and the development of novel disease control strategies. Key areas of uncertainty include: (i) the precise influence of deer abundance on tick abundance, (ii) how tick populations are regulated, (iii) assembly of host communities and tick-feeding patterns across different habitats, (iv) reservoir competence of host species, and (v) pathogenicity for humans of different genotypes of Borrelia burgdorferi. Filling these knowledge gaps will improve Lyme disease prevention and control and provide general insights into the drivers and dynamics of this emblematic multi-host–vector-borne zoonotic disease.

Nonmicrowave health and ecological effects: Overview

NASA Technical Reports Server (NTRS)

White, M. R.

1980-01-01

The potential environmental impacts due to the operation and construction of the Satellite Power System are discussed. The nonmicrowave health and ecological effects encompass impacts on the public, the terrestrial worker, the space worker, the ecology, and agriculture.

A decade of a thrips invasion in China: lessons learned.

PubMed

Wu, Shengyong; Tang, Liangde; Zhang, Xingrui; Xing, Zhenlong; Lei, Zhongren; Gao, Yulin

2017-10-11

The Western flower thrips, Frankliniella occidentalis Pergande (Thysanoptera: Thripidae) is an invasive polyphagous pest with an expanding global range that damages a wide variety of crops. F. occidentalis was first reported in China from Yunnan province during 2000, and has rapidly expanded its range since then. It is currently distributed across at least 10 provinces in China and has become a particularly devastating pest, causing substantial damage and economic losses. At present, the still heavy reliance on frequent use of insecticides for control of F. occidentalis, has lead to a series of ecological problems stemming from insecticide resistance, interspecific displacement and non-target effects. Thus, integrated pest management (IPM) programmes, multiple complementary tactics, including preventive tactics, biological controls, and judicious use of insecticides will likely provide a viable IPM strategy for control of F. occidentalis in the near future. This review provides an overview for information gained during the 10+ years since the invasion of F. occidentalis into China, reviews lessons that have been learned enhancing our overall understanding of the biology and ecology of F. occidentalis and discusses IPM practices relative to this widespread invasive insect pest.

Ecological network analysis on global virtual water trade.

PubMed

Yang, Zhifeng; Mao, Xufeng; Zhao, Xu; Chen, Bin

2012-02-07

Global water interdependencies are likely to increase with growing virtual water trade. To address the issues of the indirect effects of water trade through the global economic circulation, we use ecological network analysis (ENA) to shed insight into the complicated system interactions. A global model of virtual water flow among agriculture and livestock production trade in 1995-1999 is also built as the basis for network analysis. Control analysis is used to identify the quantitative control or dependency relations. The utility analysis provides more indicators for describing the mutual relationship between two regions/countries by imitating the interactions in the ecosystem and distinguishes the beneficiary and the contributor of virtual water trade system. Results show control and utility relations can well depict the mutual relation in trade system, and direct observable relations differ from integral ones with indirect interactions considered. This paper offers a new way to depict the interrelations between trade components and can serve as a meaningful start as we continue to use ENA in providing more valuable implications for freshwater study on a global scale.

Commoditizing Nonhuman Animals and Their Consumers: Industrial Livestock Production, Animal Welfare, and Ecological Justice

ERIC Educational Resources Information Center

McLeod-Kilmurray, Heather

2012-01-01

There is increasing research on the effects of industrial livestock production on the environment and human health, but less on the effects this has on animal welfare and ecological justice. The concept of ecological justice as a tool for achieving sustainability is gaining traction in the legal world. Klaus Bosselman defines ecological justice as…

Wildlife-friendly farming increases crop yield: evidence for ecological intensification.

PubMed

Pywell, Richard F; Heard, Matthew S; Woodcock, Ben A; Hinsley, Shelley; Ridding, Lucy; Nowakowski, Marek; Bullock, James M

2015-10-07

Ecological intensification has been promoted as a means to achieve environmentally sustainable increases in crop yields by enhancing ecosystem functions that regulate and support production. There is, however, little direct evidence of yield benefits from ecological intensification on commercial farms growing globally important foodstuffs (grains, oilseeds and pulses). We replicated two treatments removing 3 or 8% of land at the field edge from production to create wildlife habitat in 50-60 ha patches over a 900 ha commercial arable farm in central England, and compared these to a business as usual control (no land removed). In the control fields, crop yields were reduced by as much as 38% at the field edge. Habitat creation in these lower yielding areas led to increased yield in the cropped areas of the fields, and this positive effect became more pronounced over 6 years. As a consequence, yields at the field scale were maintained--and, indeed, enhanced for some crops--despite the loss of cropland for habitat creation. These results suggested that over a 5-year crop rotation, there would be no adverse impact on overall yield in terms of monetary value or nutritional energy. This study provides a clear demonstration that wildlife-friendly management which supports ecosystem services is compatible with, and can even increase, crop yields. © 2015 The Authors.

Wildlife-friendly farming increases crop yield: evidence for ecological intensification

PubMed Central

Pywell, Richard F.; Heard, Matthew S.; Woodcock, Ben A.; Hinsley, Shelley; Ridding, Lucy; Nowakowski, Marek; Bullock, James M.

2015-01-01

Ecological intensification has been promoted as a means to achieve environmentally sustainable increases in crop yields by enhancing ecosystem functions that regulate and support production. There is, however, little direct evidence of yield benefits from ecological intensification on commercial farms growing globally important foodstuffs (grains, oilseeds and pulses). We replicated two treatments removing 3 or 8% of land at the field edge from production to create wildlife habitat in 50–60 ha patches over a 900 ha commercial arable farm in central England, and compared these to a business as usual control (no land removed). In the control fields, crop yields were reduced by as much as 38% at the field edge. Habitat creation in these lower yielding areas led to increased yield in the cropped areas of the fields, and this positive effect became more pronounced over 6 years. As a consequence, yields at the field scale were maintained—and, indeed, enhanced for some crops—despite the loss of cropland for habitat creation. These results suggested that over a 5-year crop rotation, there would be no adverse impact on overall yield in terms of monetary value or nutritional energy. This study provides a clear demonstration that wildlife-friendly management which supports ecosystem services is compatible with, and can even increase, crop yields. PMID:26423846

Effect of correlations on controllability transition in network control

PubMed Central

Nie, Sen; Wang, Xu-Wen; Wang, Bing-Hong; Jiang, Luo-Luo

2016-01-01

The network control problem has recently attracted an increasing amount of attention, owing to concerns including the avoidance of cascading failures of power-grids and the management of ecological networks. It has been proven that numerical control can be achieved if the number of control inputs exceeds a certain transition point. In the present study, we investigate the effect of degree correlation on the numerical controllability in networks whose topological structures are reconstructed from both real and modeling systems, and we find that the transition point of the number of control inputs depends strongly on the degree correlation in both undirected and directed networks with moderately sparse links. More interestingly, the effect of the degree correlation on the transition point cannot be observed in dense networks for numerical controllability, which contrasts with the corresponding result for structural controllability. In particular, for directed random networks and scale-free networks, the influence of the degree correlation is determined by the types of correlations. Our approach provides an understanding of control problems in complex sparse networks. PMID:27063294

Sex and the shifting biodiversity dynamics of marine animals in deep time

NASA Astrophysics Data System (ADS)

Bush, Andrew M.; Hunt, Gene; Bambach, Richard K.

2016-12-01

The fossil record of marine animals suggests that diversity-dependent processes exerted strong control on biodiversification: after the Ordovician Radiation, genus richness did not trend for hundreds of millions of years. However, diversity subsequently rose dramatically in the Cretaceous and Cenozoic (145 million years ago-present), indicating that limits on diversification can be overcome by ecological or evolutionary change. Here, we show that the Cretaceous-Cenozoic radiation was driven by increased diversification in animals that transfer sperm between adults during fertilization, whereas animals that broadcast sperm into the water column have not changed significantly in richness since the Late Ordovician (˜450 million years ago). We argue that the former group radiated in part because directed sperm transfer permits smaller population sizes and additional modes of prezygotic isolation, as has been argued previously for the coincident radiation of angiosperms. Directed sperm transfer tends to co-occur with many ecological traits, such as a predatory lifestyle. Ecological specialization likely operated synergistically with mode of fertilization in driving the diversification that began during the Mesozoic marine revolution. Plausibly, the ultimate driver of diversification was an increase in food availability, but its effects on the fauna were regulated by fundamental reproductive and ecological traits.

Sex and the shifting biodiversity dynamics of marine animals in deep time

PubMed Central

Bush, Andrew M.; Hunt, Gene; Bambach, Richard K.

2016-01-01

The fossil record of marine animals suggests that diversity-dependent processes exerted strong control on biodiversification: after the Ordovician Radiation, genus richness did not trend for hundreds of millions of years. However, diversity subsequently rose dramatically in the Cretaceous and Cenozoic (145 million years ago–present), indicating that limits on diversification can be overcome by ecological or evolutionary change. Here, we show that the Cretaceous–Cenozoic radiation was driven by increased diversification in animals that transfer sperm between adults during fertilization, whereas animals that broadcast sperm into the water column have not changed significantly in richness since the Late Ordovician (∼450 million years ago). We argue that the former group radiated in part because directed sperm transfer permits smaller population sizes and additional modes of prezygotic isolation, as has been argued previously for the coincident radiation of angiosperms. Directed sperm transfer tends to co-occur with many ecological traits, such as a predatory lifestyle. Ecological specialization likely operated synergistically with mode of fertilization in driving the diversification that began during the Mesozoic marine revolution. Plausibly, the ultimate driver of diversification was an increase in food availability, but its effects on the fauna were regulated by fundamental reproductive and ecological traits. PMID:27821755

Fisheries regulatory regimes and resilience to climate change.

PubMed

Ojea, Elena; Pearlman, Isaac; Gaines, Steven D; Lester, Sarah E

2017-05-01

Climate change is already producing ecological, social, and economic impacts on fisheries, and these effects are expected to increase in frequency and magnitude in the future. Fisheries governance and regulations can alter socio-ecological resilience to climate change impacts via harvest control rules and incentives driving fisher behavior, yet there are no syntheses or conceptual frameworks for examining how institutions and their regulatory approaches can alter fisheries resilience to climate change. We identify nine key climate resilience criteria for fisheries socio-ecological systems (SES), defining resilience as the ability of the coupled system of interacting social and ecological components (i.e., the SES) to absorb change while avoiding transformation into a different undesirable state. We then evaluate the capacity of four fisheries regulatory systems that vary in their degree of property rights, including open access, limited entry, and two types of rights-based management, to increase or inhibit resilience. Our exploratory assessment of evidence in the literature suggests that these regulatory regimes vary widely in their ability to promote resilient fisheries, with rights-based approaches appearing to offer more resilience benefits in many cases, but detailed characteristics of the regulatory instruments are fundamental.

The dark side of light at night: physiological, epidemiological, and ecological consequences.

PubMed

Navara, Kristen J; Nelson, Randy J

2007-10-01

Organisms must adapt to the temporal characteristics of their surroundings to successfully survive and reproduce. Variation in the daily light cycle, for example, acts through endocrine and neurobiological mechanisms to control several downstream physiological and behavioral processes. Interruptions in normal circadian light cycles and the resulting disruption of normal melatonin rhythms cause widespread disruptive effects involving multiple body systems, the results of which can have serious medical consequences for individuals, as well as large-scale ecological implications for populations. With the invention of electrical lights about a century ago, the temporal organization of the environment has been drastically altered for many species, including humans. In addition to the incidental exposure to light at night through light pollution, humans also engage in increasing amounts of shift-work, resulting in repeated and often long-term circadian disruption. The increasing prevalence of exposure to light at night has significant social, ecological, behavioral, and health consequences that are only now becoming apparent. This review addresses the complicated web of potential behavioral and physiological consequences resulting from exposure to light at night, as well as the large-scale medical and ecological implications that may result.

Publications of the NASA Controlled Ecological Life Support System (CELSS) Program, 1979-1989

NASA Technical Reports Server (NTRS)

Wallace, Janice S.; Powers, Janet V.

1990-01-01

Publications of research sponsored by the NASA Controlled Ecological Life Support System (CELSS) Program from 1979 to 1989 are listed. The CELSS Program encompasses research and technology with the goal of developing an autonomous bioregenerative life support system that continually recycles the solid, liquid, and gaseous materials essential for human life. The bibliography is divided into four major subject areas: food production, nutritional requirements, waste management, and systems management and control.

The Controlled Ecological Life Support Systems (CELSS) research program

NASA Technical Reports Server (NTRS)

Macelroy, Robert D.

1990-01-01

The goal of the Controlled Ecological Life Support Systems (CELSS) program is to develop systems composed of biological, chemical and physical components for purposes of human life support in space. The research activities supported by the program are diverse, but are focused on the growth of higher plants, food and waste processing, and systems control. Current concepts associated with the development and operation of a bioregenerative life support system will be discussed in this paper.

Species' Traits as Predictors of Range Shifts Under Contemporary Climate Change: A Meta-analysis

NASA Astrophysics Data System (ADS)

MacLean, S. A.; Beissinger, S. R.

2016-12-01

A growing body of literature seeks to explain variation in range shifts using species' ecological and life history traits, with expectations that shifts should be greater in species with greater dispersal ability, reproductive potential, and ecological generalization. If trait-based arguments, hold, then traits would provide valuable evidence-based tools for conservation and management that could increase the accuracy of future range projections, vulnerability assessments, and predictions of novel community assemblages. However, empirical support is limited in extent and consensus, and trait-based relationships remain largely unvalidated. We conducted a comprehensive literature review of species' traits as predictors of range shifts, collecting results from over 11,000 species' responses across multiple taxa from studies that directly compared 20th century and contemporary distributions for multispecies assemblages. We then performed a meta-analysis to calculate the mean study-level effects of body size, fecundity, diet breadth, habitat breadth, and historic range limit, while directly controlling for ecological and methodological heterogeneity across studies that could bias reported effect sizes. We show that ecological and life history traits have had limited success in accounting for variation among species in range shifts over the past century. Of the five traits analyzed, only habitat breadth and historic range limit consistently supported range shift predictions across multiple studies. Fecundity, body size, and diet breadth showed no clear relationship with range shifts, and some traits identified in our literature review (e.g. migratory ecology) have consistently contradicted range shift predictions. Current understanding of species' traits as predictors of range shifts is limited, and standardized study is needed before traits can be reliably incorporated into projections of climate change impacts.

Dog Ecology and Population Studies in Lagos State, Nigeria

PubMed Central

Hambolu, Sunday E.; Dzikwi, Asabe A.; Kwaga, Jacob K.P.; Kazeem, Haruna M.; Umoh, Jarlath U.; Hambolu, Dupe A.

2014-01-01

Dog population dynamics have a major impact upon the effectiveness of rabies control strategies. As such, understanding domestic dog ecology has been recognized as central to the design of effective rabies control programmes. This study was conducted to determine the dog ecology in Lagos State using compound dog count and street dog count in the three senatorial districts (Lagos West, East and Central) of Lagos State from February, 2011 to January, 2012. A total of 546 questionnaires were distributed for the compound dog count and all were completed and returned. Various aspects of dog ecology were determined, including size, sex, breed of the dog population, management of dogs and rabies awareness among the respondents. Out of the 546 compounds surveyed, 518 (94.87%) owned at least one dog. A total of 1,427 dogs were counted from the street counts while a total of 1,447 dogs (2.8 dogs/compound) were counted from the compound count. The dogs comprised of 583 males and 864 females, out of which 64.10% are confined. The dog vaccination coverage in the dog population surveyed was 64.10% and administered majorly (91.30%) by veterinarians. Security (60%) and pets (26%) were the major reasons for keeping dogs. Majority (88.80%) of the respondents were aware of rabies and its mode of transmission, but still believed in the use of concoctions (40.40%), herbs (19.90%) and consumption of the organ of the offending dog (11.50%) for the treatment of rabies. The findings of this study showed a male: female ratio of dog to be 1:1.5 and a dog: human ratio of 1:5.6. There was also a responsible dog ownership as majority of the respondents do confine, vaccinate and provide food for their dogs. Vaccination coverage of the total dog population was however below the 70-80% target recommended by the World Health Organization to achieve herd immunity. PMID:24576383

Examining the recent climate through the lens of ecology: inferences from temporal pattern analysis.

Treesearch

Paul F. Hessburg; Ellen E. Kuhlmann; Thomas W. Swetnam

2005-01-01

Ecological theory asserts that the climate of a region exerts top-down controls on regional ecosystem patterns and processes, across space and time. To provide empirical evidence of climatic controls, it would be helpful to define climatic regions that minimized variance in key climate attributes, within climatic regions-define the periods and features of climatic...

Linear and nonlinear effects of temperature and precipitation on ecosystem properties in tidal saline wetlands

USGS Publications Warehouse

Feher, Laura C.; Osland, Michael J.; Griffith, Kereen T.; Grace, James B.; Howard, Rebecca J.; Stagg, Camille L.; Enwright, Nicholas M.; Krauss, Ken W.; Gabler, Christopher A.; Day, Richard H.; Rogers, Kerrylee

2017-01-01

Climate greatly influences the structure and functioning of tidal saline wetland ecosystems. However, there is a need to better quantify the effects of climatic drivers on ecosystem properties, particularly near climate-sensitive ecological transition zones. Here, we used climate- and literature-derived ecological data from tidal saline wetlands to test hypotheses regarding the influence of climatic drivers (i.e., temperature and precipitation regimes) on the following six ecosystem properties: canopy height, biomass, productivity, decomposition, soil carbon density, and soil carbon accumulation. Our analyses quantify and elucidate linear and nonlinear effects of climatic drivers. We quantified positive linear relationships between temperature and above-ground productivity and strong positive nonlinear (sigmoidal) relationships between (1) temperature and above-ground biomass and canopy height and (2) precipitation and canopy height. Near temperature-controlled mangrove range limits, small changes in temperature are expected to trigger comparatively large changes in biomass and canopy height, as mangrove forests grow, expand, and, in some cases, replace salt marshes. However, within these same transition zones, temperature-induced changes in productivity are expected to be comparatively small. Interestingly, despite the significant above-ground height, biomass, and productivity relationships across the tropical–temperate mangrove–marsh transition zone, the relationships between temperature and soil carbon density or soil carbon accumulation were not significant. Our literature review identifies several ecosystem properties and many regions of the world for which there are insufficient data to fully evaluate the influence of climatic drivers, and the identified data gaps can be used by scientists to guide future research. Our analyses indicate that near precipitation-controlled transition zones, small changes in precipitation are expected to trigger comparatively large changes in canopy height. However, there are scant data to evaluate the influence of precipitation on other ecosystem properties. There is a need for more decomposition data across climatic gradients, and to advance understanding of the influence of changes in precipitation and freshwater availability, additional ecological data are needed from tidal saline wetlands in arid climates. Collectively, our results can help scientists and managers better anticipate the linear and nonlinear ecological consequences of climate change for coastal wetlands.

Experimental droughts: Are precipitation variability and methodological trends hindering our understanding of ecological sensitivities to drought?

NASA Astrophysics Data System (ADS)

Hoover, D. L.; Wilcox, K.; Young, K. E.

2017-12-01

Droughts are projected to increase in frequency and intensity with climate change, which may have dramatic and prolonged effects on ecosystem structure and function. There are currently hundreds of published, ongoing, and new drought experiments worldwide aimed to assess ecosystem sensitivities to drought and identify the mechanisms governing ecological resistance and resilience. However, to date, the results from these experiments have varied widely, and thus patterns of drought sensitivities have been difficult to discern. This lack of consensus at the field scale, limits the abilities of experiments to help improve land surface models, which often fail to realistically simulate ecological responses to extreme events. This is unfortunate because models offer an alternative, yet complementary approach to increase the spatial and temporal assessment of ecological sensitivities to drought that are not possible in the field due to logistical and financial constraints. Here we examined 89 published drought experiments, along with their associated historical precipitation records to (1) identify where and how drought experiments have been imposed, (2) determine the extremity of drought treatments in the context of historical climate, and (3) assess the influence of precipitation variability on drought experiments. We found an overall bias in drought experiments towards short-term, extreme experiments in water-limited ecosystems. When placed in the context of local historical precipitation, most experimental droughts were extreme, with 61% below the 5th, and 43% below the 1st percentile. Furthermore, we found that interannual precipitation variability had a large and potentially underappreciated effect on drought experiments due to the co-varying nature of control and drought treatments. Thus detecting ecological effects in experimental droughts is strongly influenced by the interaction between drought treatment magnitude, precipitation variability, and key physiological thresholds. The results from this study have important implication for the design and interpretation of drought experiments as well as integrating field results with land surface models.

Changes in mouse gastrointestinal microbial ecology with ingestion of kale.

PubMed

Uyeno, Y; Katayama, S; Nakamura, S

2014-09-01

Kale, a cultivar of Brassica oleracea, has attracted a great deal of attention because of its health-promoting effects, which are thought to be exerted through modulation of the intestinal microbiota. The present study was performed to investigate the effects of kale ingestion on the gastrointestinal microbial ecology of mice. 21 male C57BL/6J mice were divided into three groups and housed in a specific pathogen-free facility. The animals were fed either a control diet or experimental diets supplemented with different commercial kale products for 12 weeks. Contents of the caecum and colon of the mice were processed for the determination of active bacterial populations by a bacterial rRNA-based quantification method and short-chain fatty acids by HPLC. rRNAs of Bacteroides-Prevotella, the Clostridium coccoides-Eubacterium rectale group, and Clostridium leptum subgroup constituted the major fraction of microbiota regardless of the composition of the diet. The ratio of Firmicutes to Bacteroidetes was higher in the colon samples of one of the kale diet groups than in the control. The colonic butyrate level was also higher with the kale-supplemented diet. Overall, the ingestion of kale tended to either increase or decrease the activity of specific bacterial groups in the mouse gastrointestinal tract, however, the effect might vary depending on the nutritional composition.

Memory retrieval of everyday information under stress.

PubMed

Stock, Lisa-Marie; Merz, Christian J

2018-07-01

Psychosocial stress is known to crucially influence learning and memory processes. Several studies have already shown an impairing effect of elevated cortisol concentrations on memory retrieval. These studies mainly used learning material consisting of stimuli with a limited ecological validity. When using material with a social contextual component or with educational relevant material both impairing and enhancing stress effects on memory retrieval could be observed. In line with these latter studies, the present experiment also used material with a higher ecological validity (a coherent text consisting of daily relevant numeric, figural and verbal information). After encoding, retrieval took place 24 h later after exposure to psychosocial stress or a control procedure (20 healthy men per group). The stress group was further subdivided into cortisol responders and non-responders. Results showed a significantly impaired retrieval of everyday information in non-responders compared to responders and controls. Altogether, the present findings indicate the need of an appropriate cortisol response for the successful memory retrieval of everyday information. Thus, the present findings suggest that cortisol increases - contrary to a stressful experience per se - seem to play a protective role for retrieving everyday information. Additionally, it could be speculated that the previously reported impairing stress effects on memory retrieval might depend on the used learning material. Copyright © 2018 Elsevier Inc. All rights reserved.

Using Economic Incentives to Manage Stormwater Runoff in ...

EPA Pesticide Factsheets

Communities nationwide are facing increased responsibility for controlling stormwater runoff, and, subsequently, rising costs of stormwater management. In this report we describe and test a methodology that can be used by communities to focus limited budgets on the most efficient and ecologically-effective installation of stormwater management practices. The overall project has two primary objectives: (1) to test the use of an auction to cost-effectively allocate stormwater management practices among landowners, and (2) to determine the effectiveness of the resulting implementation in terms of hydrological, water quality, and ecological measures. Here, we describe the theories, methods, and criteria used to distribute rain gardens and rain barrels to homeowners in a small, midwestern watershed. The first round of the reverse auction in 2007 resulted in 50 rain gardens and 100 rain barrels installed at 67 of the approximately 350 residential properties in the experimental watershed. In 2008, the auction was repeated and we accepted bids for an additional 35 rain gardens and 74 rain barrels. Stormwater management practices were distributed relatively evenly throughout the watershed and are expected to result in significant improvements in stream quality. We describe our monitoring approach, including 1) parcel-scale hydrology and water quality monitoring of selected rain gardens, and 2) stream monitoring following before-after-control-impact approach for as

Disease ecology and the global emergence of zoonotic pathogens.

PubMed

Wilcox, Bruce A; Gubler, Duane J

2005-09-01

The incidence and frequency of epidemic transmission of zoonotic diseases, both known and newly recognized, has increased dramatically in the past 30 years. It is thought that this dramatic disease emergence is primarily the result of the social, demographic, and environmental transformation that has occurred globally since World War II. However, the causal linkages have not been elucidated. Investigating emerging zoonotic pathogens as an ecological phenomenon can provide significant insights as to why some of these pathogens have jumped species and caused major epidemics in humans. A review of concepts and theory from biological ecology and of causal factors in disease emergence previously described suggests a general model of global zoonotic disease emergence. The model links demographic and societal factors to land use and land cover change whose associated ecological factors help explain disease emergence. The scale and magnitude of these changes are more significant than those associated with climate change, the effects of which are largely not yet understood. Unfortunately, the complex character and non-linear behavior of the human-natural systems in which host-pathogen systems are embedded makes specific incidences of disease emergence or epidemics inherently difficult to predict. Employing a complex systems analytical approach, however, may show how a few key ecological variables and system properties, including the adaptive capacity of institutions, explains the emergence of infectious diseases and how an integrated, multi-level approach to zoonotic disease control can reduce risk.

Ecological and taphonomical influences on coccoliths in surface sediments in the shelf of the Yellow and East China Seas

NASA Astrophysics Data System (ADS)

Jin, Xiaobo; Liu, Chuanlian

2017-05-01

Coccoliths, combined with sediment grain size, carbonate calcium and organic matters content, were analyzed to assess the ecological and taphonomical influences on coccolith distribution patterns in surface sediments in the continental shelf of the Yellow and East China Seas. Coccolith abundances ranged from 0 to 2.08×109 coccoliths g-1 sediment. The increasing abundance from the coastal inner shelf to the seaward middle shelf generally reflects the ecological fact that living coccolithophores are more abundant in the mesotrophic shelf waters than in the eutrophic coastal waters, although their deposits are still controlled by taphonomical effects, such as bottom (tidal) currents and calcite preservation conditions. Most abundant coccoliths are found in the fine-grained sediments of southwestern Cheju Island, where both ecology and taphonomy favor coccolith preservation. Still, large densities of coccoliths (>108 coccoliths g-1 sediment) are also found in coarse-grained relict sediments in the middle shelf. Coccolith assemblages were predominated by Gephyrocapsa oceanica and Emiliania huxleyi. The relative abundance of E. huxleyi, in addition to ecological reasons, may relate to selective post-mortem dissolution, since small E. huxleyi coccoliths are more susceptible to dissolution. Coccolith calcite has minor contributions (<1% to 12%) to total sediment CaCO3, and the main parts are attributed to terrigenous CaCO3 debris and relict shell fragments.

The cystic fibrosis microbiome in an ecological perspective and its impact in antibiotic therapy.

PubMed

Magalhães, Andreia P; Azevedo, Nuno F; Pereira, Maria O; Lopes, Susana P

2016-02-01

The recent focus on the cystic fibrosis (CF) complex microbiome has led to the recognition that the microbes can interact between them and with the host immune system, affecting the disease progression and treatment routes. Although the main focus remains on the interactions between traditional pathogens, growing evidence supports the contribution and the role of emergent species. Understanding the mechanisms and the biological effects involved in polymicrobial interactions may be the key to improve effective therapies and also to define new strategies for disease control. This review focuses on the interactions between microbe-microbe and host-microbe, from an ecological point of view, discussing their impact on CF disease progression. There are increasing indications that these interactions impact the success of antimicrobial therapy. Consequently, a new approach where therapy is personalized to patients by taking into account their individual CF microbiome is suggested.

Predator identity more than predator richness structures aquatic microbial assemblages in Sarracenia purpurea leaves.

PubMed

Canter, Erin J; Cuellar-Gempeler, Catalina; Pastore, Abigail I; Miller, Thomas E; Mason, Olivia U

2018-03-01

The importance of predators in influencing community structure is a well-studied area of ecology. However, few studies test ecological hypotheses of predation in multi-predator microbial communities. The phytotelmic community found within the water-filled leaves of the pitcher plant, Sarracenia purpurea, exhibits a simple trophic structure that includes multiple protozoan predators and microbial prey. Using this system, we sought to determine whether different predators target distinct microorganisms, how interactions among protozoans affect resource (microorganism) use, and how predator diversity affects prey community diversity. In particular, we endeavored to determine if protozoa followed known ecological patterns such as keystone predation or generalist predation. For these experiments, replicate inquiline microbial communities were maintained for seven days with five protozoan species. Microbial community structure was determined by 16S rRNA gene amplicon sequencing (iTag) and analysis. Compared to the control (no protozoa), two ciliates followed patterns of keystone predation by increasing microbial evenness. In pairwise competition treatments with a generalist flagellate, prey communities resembled the microbial communities of the respective keystone predator in monoculture. The relative abundance of the most common bacterial Operational Taxonomic Unit (OTU) in our system decreased compared to the control in the presence of these ciliates. This OTU was 98% similar to a known chitin degrader and nitrate reducer, important functions for the microbial community and the plant host. Collectively, the data demonstrated that predator identity had a greater effect on prey diversity and composition than overall predator diversity. © 2018 by the Ecological Society of America.

Feasibility and coexistence of large ecological communities.

PubMed

Grilli, Jacopo; Adorisio, Matteo; Suweis, Samir; Barabás, György; Banavar, Jayanth R; Allesina, Stefano; Maritan, Amos

2017-02-24

The role of species interactions in controlling the interplay between the stability of ecosystems and their biodiversity is still not well understood. The ability of ecological communities to recover after small perturbations of the species abundances (local asymptotic stability) has been well studied, whereas the likelihood of a community to persist when the conditions change (structural stability) has received much less attention. Our goal is to understand the effects of diversity, interaction strengths and ecological network structure on the volume of parameter space leading to feasible equilibria. We develop a geometrical framework to study the range of conditions necessary for feasible coexistence. We show that feasibility is determined by few quantities describing the interactions, yielding a nontrivial complexity-feasibility relationship. Analysing more than 100 empirical networks, we show that the range of coexistence conditions in mutualistic systems can be analytically predicted. Finally, we characterize the geometric shape of the feasibility domain, thereby identifying the direction of perturbations that are more likely to cause extinctions.

Feasibility and coexistence of large ecological communities

PubMed Central

Grilli, Jacopo; Adorisio, Matteo; Suweis, Samir; Barabás, György; Banavar, Jayanth R.; Allesina, Stefano; Maritan, Amos

2017-01-01

The role of species interactions in controlling the interplay between the stability of ecosystems and their biodiversity is still not well understood. The ability of ecological communities to recover after small perturbations of the species abundances (local asymptotic stability) has been well studied, whereas the likelihood of a community to persist when the conditions change (structural stability) has received much less attention. Our goal is to understand the effects of diversity, interaction strengths and ecological network structure on the volume of parameter space leading to feasible equilibria. We develop a geometrical framework to study the range of conditions necessary for feasible coexistence. We show that feasibility is determined by few quantities describing the interactions, yielding a nontrivial complexity–feasibility relationship. Analysing more than 100 empirical networks, we show that the range of coexistence conditions in mutualistic systems can be analytically predicted. Finally, we characterize the geometric shape of the feasibility domain, thereby identifying the direction of perturbations that are more likely to cause extinctions. PMID:28233768

Ecological theory as a foundation to control pathogenic invasion in aquaculture

PubMed Central

De Schryver, Peter; Vadstein, Olav

2014-01-01

Detrimental host–pathogen interactions are a normal phenomenon in aquaculture animal production, and have been counteracted by prophylactic use of antibiotics. Especially, the youngest life stages of cultivated aquatic animals are susceptible to pathogen invasion, resulting in disease and mortality. To establish a more sustainable aquatic food production, there is a need for new microbial management strategies that focus on ‘join them' and not the traditional ‘beat them' approaches. We argue that ecological theory could serve as a foundation for developing sustainable microbial management methods that prevent pathogenic disease in larviculture. Management of the water microbiota in aquaculture systems according to ecological selection principles has been shown to decrease opportunistic pathogen pressure and to result in an improved performance of the cultured animals. We hypothesize that manipulation of the biodiversity of the gut microbiota can increase the host's resistance against pathogenic invasion and infection. However, substantial barriers need to be overcome before active management of the intestinal microbiota can effectively be applied in larviculture. PMID:24892581

[Effects of land use structure change on regional ecological health--taking Shapingba County as an example].

PubMed

Wang, Cheng; Wei, Chaofu; Gao, Ming; Luo, Guanglian; Jiang, Wei

2005-12-01

Land resource is the carrier for the exchange of matter, energy and information flows, while the change velocity and the intensity of land use has strong effects on the ecological processes such as matter circulation, energy flow, and biologic diversity. Land use structure change will alter the type, area, and spatial distribution of ecosystem, and in the meantime, result in the changes of regional ecological health. Employing the principles and methods of landscape ecology, and through endowing relative ecological value to land use type, this paper analyzed the charaeteristics of recent 10 years land use change in Shapingba County of Chongqing, and discussed the effects of land use change on regional ecological health, aimed to provide scientific references for land use planning and sustainable land resource utilization. The results indicated that transformation often occurred among different land use types, and the land use structure in each transformation phase differed quite obviously. Under different land use structure, there was a great disparity in relative ecological value of sub-ecosystems, which played various roles in regional ecological health. In general, the regional relative ecological value embodied both increase and decrease. In the future, the relative ecological value of sub-ecosystem would represent three tendencies, i.e., increase first and decrease then, continuous decrease, and continuous increase. The situation of regional ecological health would gradually become better.

Warming and Resource Availability Shift Food Web Structure and Metabolism

PubMed Central

O'Connor, Mary I.; Piehler, Michael F.; Leech, Dina M.; Anton, Andrea; Bruno, John F.

2009-01-01

Climate change disrupts ecological systems in many ways. Many documented responses depend on species' life histories, contributing to the view that climate change effects are important but difficult to characterize generally. However, systematic variation in metabolic effects of temperature across trophic levels suggests that warming may lead to predictable shifts in food web structure and productivity. We experimentally tested the effects of warming on food web structure and productivity under two resource supply scenarios. Consistent with predictions based on universal metabolic responses to temperature, we found that warming strengthened consumer control of primary production when resources were augmented. Warming shifted food web structure and reduced total biomass despite increases in primary productivity in a marine food web. In contrast, at lower resource levels, food web production was constrained at all temperatures. These results demonstrate that small temperature changes could dramatically shift food web dynamics and provide a general, species-independent mechanism for ecological response to environmental temperature change. PMID:19707271

Systematic review for geo-authentic Lonicerae Japonicae Flos.

PubMed

Yang, Xingyue; Liu, Yali; Hou, Aijuan; Yang, Yang; Tian, Xin; He, Liyun

2017-06-01

In traditional Chinese medicine, Lonicerae Japonicae Flos is commonly used as anti-inflammatory, antiviral, and antipyretic herbal medicine, and geo-authentic herbs are believed to present the highest quality among all samples from different regions. To discuss the current situation and trend of geo-authentic Lonicerae Japonicae Flos, we searched Chinese Biomedicine Literature Database, Chinese Journal Full-text Database, Chinese Scientific Journal Full-text Database, Cochrane Central Register of Controlled Trials, Wanfang, and PubMed. We investigated all studies up to November 2015 pertaining to quality assessment, discrimination, pharmacological effects, planting or processing, or ecological system of geo-authentic Lonicerae Japonicae Flos. Sixty-five studies mainly discussing about chemical fingerprint, component analysis, planting and processing, discrimination between varieties, ecological system, pharmacological effects, and safety were systematically reviewed. By analyzing these studies, we found that the key points of geo-authentic Lonicerae Japonicae Flos research were quality and application. Further studies should focus on improving the quality by selecting the more superior of all varieties and evaluating clinical effectiveness.

An Ecological Approach to the Design of UAV Ground Control Station (GCS) Status Displays

NASA Technical Reports Server (NTRS)

Dowell, Susan; Morphew, Ephimia; Shively, Jay

2003-01-01

Use of UAVs in military and commercial applications will continue to increase. However, there has been limited research devoted to UAV GCS design. The current study employed an ecological approach to interfac e design. Ecological Interface Design (EID) can be characterized as r epresenting the properties of a system, such that an operator is enco uraged to use skill-based behavior when problem solving. When more ef fortful cognitive processes become necessary due to unfamiliar situations, the application of EID philosophy supports the application of kn owledge-based behavior. With advances toward multiple UAV command and control, operators need GCS interfaces designed to support understan ding of complex systems. We hypothesized that use of EID principles f or the display of UAV status information would result in better opera tor performance and situational awareness, while decreasing workload. Pilots flew a series of missions with three UAV GCS displays of statu s information (Alphanumeric, Ecological, and Hybrid display format). Measures of task performance, Situational Awareness, and workload dem onstrated the benefits of using an ecological approach to designing U AV GCS displays. The application of ecological principles to the design of UAV GCSs is a promising area for improving UAV operations.

Biodiversity and ecosystem risks arising from using guppies to control mosquitoes

PubMed Central

Frauendorf, Therese C.; Marques, Piata S.; Mackenzie, Richard A.; Manna, Luisa R.; Mazzoni, Rosana; Phillip, Dawn A. T.; Warbanski, Misha L.; Zandonà, Eugenia

2016-01-01

Deploying mosquito predators such as the guppy (Poecilia reticulata) into bodies of water where mosquitoes breed is a common strategy for limiting the spread of disease-carrying mosquitoes. Here, we draw on studies from epidemiology, conservation, ecology and evolution to show that the evidence for the effectiveness of guppies in controlling mosquitoes is weak, that the chances of accidental guppy introduction into local ecosystems are large, and that guppies can easily establish populations and damage these aquatic ecosystems. We highlight several knowledge and implementation gaps, and urge that this approach is either abandoned in favour of more effective strategies or that it is used much more rigorously. Controlling mosquitoes does not need to come at the expense of freshwater biodiversity. PMID:28120806

Visioning the Future: Scenarios Modeling of the Florida Coastal Everglades

NASA Astrophysics Data System (ADS)

Flower, Hilary; Rains, Mark; Fitz, Carl

2017-11-01

In this paper, we provide screening-level analysis of plausible Everglades ecosystem response by 2060 to sea level rise (0.50 m) interacting with macroclimate change (1.5 °C warming, 7% increase in evapotranspiration, and rainfall that either increases or decreases by 10%). We used these climate scenarios as input to the Ecological Landscape Model to simulate changes to seven interactive hydro-ecological metrics. Mangrove forest and other marine influences migrated up to 15 km inland in both scenarios, delineated by the saltwater front. Freshwater habitat area decreased by 25-30% under our two climate change scenarios and was largely replaced by mangroves and, in the increased rainfall scenario, open water as well. Significant mangroves drowned along northern Florida Bay in both climate change scenarios due to sea level rise. Increased rainfall of 10% provided significant benefits to the spatial and temporal salinity regime within the marine-influenced zone, providing a more gradual and natural adjustment for at-risk flora and fauna. However, increased rainfall also increased the risk of open water, due to water depths that inhibited mangrove establishment and reduced peat accumulation rates. We infer that ecological effects related to sea level rise may occur in the extreme front-edge of saltwater intrusion, that topography will control the incursion of this zone as sea level rises, and that differences in freshwater availability will have ecologically significant effects on ecosystem resilience through the temporal and spatial pattern of salinity changes.

Visioning the Future: Scenarios Modeling of the Florida Coastal Everglades.

PubMed

Flower, Hilary; Rains, Mark; Fitz, Carl

2017-11-01

In this paper, we provide screening-level analysis of plausible Everglades ecosystem response by 2060 to sea level rise (0.50 m) interacting with macroclimate change (1.5 °C warming, 7% increase in evapotranspiration, and rainfall that either increases or decreases by 10%). We used these climate scenarios as input to the Ecological Landscape Model to simulate changes to seven interactive hydro-ecological metrics. Mangrove forest and other marine influences migrated up to 15 km inland in both scenarios, delineated by the saltwater front. Freshwater habitat area decreased by 25-30% under our two climate change scenarios and was largely replaced by mangroves and, in the increased rainfall scenario, open water as well. Significant mangroves drowned along northern Florida Bay in both climate change scenarios due to sea level rise. Increased rainfall of 10% provided significant benefits to the spatial and temporal salinity regime within the marine-influenced zone, providing a more gradual and natural adjustment for at-risk flora and fauna. However, increased rainfall also increased the risk of open water, due to water depths that inhibited mangrove establishment and reduced peat accumulation rates. We infer that ecological effects related to sea level rise may occur in the extreme front-edge of saltwater intrusion, that topography will control the incursion of this zone as sea level rises, and that differences in freshwater availability will have ecologically significant effects on ecosystem resilience through the temporal and spatial pattern of salinity changes.

Sex ratio variation shapes the ecological effects of a globally introduced freshwater fish

PubMed Central

Fryxell, David C.; Arnett, Heather A.; Apgar, Travis M.; Kinnison, Michael T.; Palkovacs, Eric P.

2015-01-01

Sex ratio and sexual dimorphism have long been of interest in population and evolutionary ecology, but consequences for communities and ecosystems remain untested. Sex ratio could influence ecological conditions whenever sexual dimorphism is associated with ecological dimorphism in species with strong ecological interactions. We tested for ecological implications of sex ratio variation in the sexually dimorphic western mosquitofish, Gambusia affinis. This species causes strong pelagic trophic cascades and exhibits substantial variation in adult sex ratios. We found that female-biased populations induced stronger pelagic trophic cascades compared with male-biased populations, causing larger changes to key community and ecosystem responses, including zooplankton abundance, phytoplankton abundance, productivity, pH and temperature. The magnitude of such effects indicates that sex ratio is important for mediating the ecological role of mosquitofish. Because both sex ratio variation and sexual dimorphism are common features of natural populations, our findings should encourage broader consideration of the ecological significance of sex ratio variation in nature, including the relative contributions of various sexually dimorphic traits to these effects. PMID:26490793

[Chagas's disease and deep ecology: the anti-vectorial fight in question].

PubMed

Siqueira-Batista, Rodrigo; Gomes, Andréia Patrícia; Rôças, Giselle; Cotta, Rosângela Minardi Mitre; Rubião, Eduardo Cárdenas Nogueira; Pissinatti, Alcides

2011-02-01

The inter-relations between man and the environment are among the main themes currently debated by the Brazilian public health. On such horizon, the questions concerning Chagas's disease are found to remain specially in the scope of the directed actions of control to the triatomine, the anti-vectorial fight , though already a century since its first description by Carlos Chagas, a major epidemiological problem in Latin America. Based on these considerations the present article will seek to discuss the main ecological aspects related to the American trypanosomiasis, emphasizing the control of the vectorial transmission in the context of the deep ecology.

Disentangling the effects of predator hunting mode and habitat domain on the top-down control of insect herbivores.

PubMed

Woodcock, Ben A; Heard, Matthew S

2011-03-01

1. Polyphagous predatory invertebrates play a key role in the top-down control of insect herbivores. However, predicting predation risk for herbivores is not a simple function of predator species richness. Predation risk may be reduced or enhanced depending on the functional characteristics predator species. We predict that where predator species spatially overlap this will reduce predation risk for herbivores by allowing negative inter-specific interaction between predators to occur. Where increased predation risk occurs, we also predict that this will have a cascading effect through the food chain reducing plant growth. 2. We used a substitutive replicated block design to identify the effect of similarity and dissimilarity in predator hunting mode (e.g. 'sit and wait', 'sit and pursue', and 'active') and habitat domain (e.g. canopy or ground) on the top-down control of planthoppers in grasslands. Predators included within the mesocosms were randomly selected from a pool of 17 local species. 3. Predation risk was reduced where predators shared the same habitat domain, independent of whether they shared hunting modes. Where predators shared the same habitat domains, there was some evidence that this had a cascading negative effect on the re-growth of grass biomass. Where predator habitat domains did not overlap, there were substitutable effects on predation risk to planthoppers. Predation risk for planthoppers was affected by taxonomic identity of predator species, i.e. whether they were beetles, spiders or true bugs. 4. Our results indicated that in multi-predator systems, the risk of predation is typically reduced. Consideration of functional characteristics of individual species, in particular aspects of habitat domain and hunting mode, are crucial in predicting the effects of multi-predator systems on the top-down control of herbivores. © 2010 The Authors. Journal of Animal Ecology © 2010 British Ecological Society.

The significance of the effect of stand density upon the weather beneath the canopy

Treesearch

G. M. Jemison

1934-01-01

During the middle of the nineteenth century forests were believed to have important influences on climate. As climate was more thoroughly understood it became evident that the major climatic controls were beyond the influence of forest cover, a finding which wholly discredited the earlier conclusions. It was evident to the forester and student of ecology, however, that...

Effects of climate on emerald ash borer mortality and the potential for ash survival in North America

Treesearch

Ryan D. DeSantis; W. Keith Moser; Dale D. Gormanson; Marshall G. Bartlett; Bradley Vermunt

2013-01-01

Non-native invasive insects such as the emerald ash borer (Agrilus planipennis Fairmaire; EAB) cause billions of dollars; worth of economic damage and unquantifiable but substantial ecological damage in North America each year. There are methods to mitigate, contain, control, or even eradicate some non-native invasive insects, but so far the spread...

Fertilization effects on forest carbon storage and exchange, and net primary production: A new hybrid process model for stand management

Treesearch

D. A. Sampson; R. H. Waring; C. A. Maier; C. M. Gough; M. J. Ducey; K. H. Johnsen

2006-01-01

A critical ecological question in plantation management is whether fertilization, which generally increases yield, results in enhanced C sequestration over short rotations. We present a rotation-length hybrid process model (SECRETS-3PG) that was calibrated (using control treatments; CW) and verified (using fertilized treatments; FW) using daily estimates of H

Fertilization effects on forest carbon storage and exchange, and net primary production: a new hybrid process model for stand management

Treesearch

D.A. Sampson; R.H. Waring; C.A. Maier; C.M. Gough; M.J. Ducey; K.H. Kohnsen

2006-01-01

A critical ecological question in plantation management is whether fertilization, which generally increases yield, results in enhanced C sequestration over short rotations. We present a rotation-length hybrid process model (SECRETS-3PG) that was calibrated (using control treatments; CW) and verified (using fertilized treatments; FW) using daily estimates of H

Patterns and consequences of re-invasion into a Hawaiian dry forest restoration

Treesearch

Erin J. Questad; Jarrod M. Thaxton; Susan Cordell

2012-01-01

The restoration of native plant diversity may be an effective tool for weed control, but its use has not been tested in the heavily invaded Hawaiian dry forest ecosystem. In addition, the ecological mechanisms by which invasive plants may cause declines in native plant diversity are generally not well understood. We examined invasion resistance and the relationships...

Estimating the Occurrence of Child Maltreatment and Risk-Factor Effects: Benefits of a Mixed-Design Strategy in Epidemiologic Research.

ERIC Educational Resources Information Center

Bertolli, Jeanne; And Others

1995-01-01

This article discusses methodologic limitations of four observational study designs (ecologic, case-control, cross-sectional, and cohort) that dominate the child abuse and neglect literature and identifies key features of an "ideal" study of child maltreatment. It proposes a new mixed-design strategy, which improves ability to identify child…

Associations Between Minimum Wage Policy and Access to Health Care: Evidence From the Behavioral Risk Factor Surveillance System, 1996–2007

PubMed Central

Zimmerman, Frederick J.; Ralston, James D.; Martin, Diane P.

2011-01-01

Objectives. We examined whether minimum wage policy is associated with access to medical care among low-skilled workers in the United States. Methods. We used multilevel logistic regression to analyze a data set consisting of individual-level indicators of uninsurance and unmet medical need from the Behavioral Risk Factor Surveillance System and state-level ecological controls from the US Census, Bureau of Labor Statistics, and several other sources in all 50 states and the District of Columbia between 1996 and 2007. Results. Higher state-level minimum wage rates were associated with significantly reduced odds of reporting unmet medical need after control for the ecological covariates, substate region fixed effects, and individual demographic and health characteristics (odds ratio = 0.853; 95% confidence interval = 0.750, 0.971). Minimum wage rates were not significantly associated with being uninsured. Conclusions. Higher minimum wages may be associated with a reduced likelihood of experiencing unmet medical need among low-skilled workers, and do not appear to be associated with uninsurance. These findings appear to refute the suggestion that minimum wage laws have detrimental effects on access to health care, as opponents of the policies have suggested. PMID:21164102

Pseudomonas aeruginosa in premise plumbing of large buildings.

PubMed

Bédard, Emilie; Prévost, Michèle; Déziel, Eric

2016-12-01

Pseudomonas aeruginosa is an opportunistic bacterial pathogen that is widely occurring in the environment and is recognized for its capacity to form or join biofilms. The present review consolidates current knowledge on P. aeruginosa ecology and its implication in healthcare facilities premise plumbing. The adaptability of P. aeruginosa and its capacity to integrate the biofilm from the faucet and the drain highlight the role premise plumbing devices can play in promoting growth and persistence. A meta-analysis of P. aeruginosa prevalence in faucets (manual and electronic) and drains reveals the large variation in device positivity reported and suggest the high variability in the sampling approach and context as the main reason for this variation. The effects of the operating conditions that prevail within water distribution systems (disinfection, temperature, and hydraulic regime) on the persistence of P. aeruginosa are summarized. As a result from the review, recommendations for proactive control measures of water contamination by P. aeruginosa are presented. A better understanding of the ecology of P. aeruginosa and key influencing factors in premise plumbing are essential to identify culprit areas and implement effective control measures. © 2016 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

Associations between minimum wage policy and access to health care: evidence from the Behavioral Risk Factor Surveillance System, 1996-2007.

PubMed

McCarrier, Kelly P; Zimmerman, Frederick J; Ralston, James D; Martin, Diane P

2011-02-01

We examined whether minimum wage policy is associated with access to medical care among low-skilled workers in the United States. We used multilevel logistic regression to analyze a data set consisting of individual-level indicators of uninsurance and unmet medical need from the Behavioral Risk Factor Surveillance System and state-level ecological controls from the US Census, Bureau of Labor Statistics, and several other sources in all 50 states and the District of Columbia between 1996 and 2007. Higher state-level minimum wage rates were associated with significantly reduced odds of reporting unmet medical need after control for the ecological covariates, substate region fixed effects, and individual demographic and health characteristics (odds ratio = 0.853; 95% confidence interval = 0.750, 0.971). Minimum wage rates were not significantly associated with being uninsured. Higher minimum wages may be associated with a reduced likelihood of experiencing unmet medical need among low-skilled workers, and do not appear to be associated with uninsurance. These findings appear to refute the suggestion that minimum wage laws have detrimental effects on access to health care, as opponents of the policies have suggested.

Guiding the development of a controlled ecological life support system

NASA Technical Reports Server (NTRS)

Mason, R. M. (Editor); Carden, J. L. (Editor)

1979-01-01

The workshop is reported which was held to establish guidelines for future development of ecological support systems, and to develop a group of researchers who understand the interdisciplinary requirements of the overall program.

Controlled Ecological Life Support System Breadboard Project - 1988

NASA Technical Reports Server (NTRS)

Knott, W. M.

1989-01-01

The Controlled Ecological Life Support System (CELSS) Breadboard Project, NASA's effort to develop the technology required to produce a functioning bioregenerative system, is discussed. The different phases of the project and its current status are described. The relationship between the project components are shown, and major project activities for fiscal years 1989-1993 are listed. The biomass production chamber to be used by the project is described.

Preparation and analysis of standardized waste samples for Controlled Ecological Life Support Systems (CELSS)

NASA Technical Reports Server (NTRS)

Carden, J. L.; Browner, R.

1982-01-01

The preparation and analysis of standardized waste samples for controlled ecological life support systems (CELSS) are considered. Analysis of samples from wet oxidation experiments, the development of ion chromatographic techniques utilizing conventional high pressure liquid chromatography (HPLC) equipment, and an investigation of techniques for interfacing an ion chromatograph (IC) with an inductively coupled plasma optical emission spectrometer (ICPOES) are discussed.

Understanding the dynamics of sustainable social-ecological systems: human behavior, institutions, and regulatory feedback networks.

PubMed

Anderies, John M

2015-02-01

I present a general mathematical modeling framework that can provide a foundation for the study of sustainability in social- ecological systems (SESs). Using basic principles from feedback control and a sequence of specific models from bioeconomics and economic growth, I outline several mathematical and empirical challenges associated with the study of sustainability of SESs. These challenges are categorized into three classes: (1) the social choice of performance measures, (2) uncertainty, and (3) collective action. Finally, I present some opportunities for combining stylized dynamical systems models with empirical data on human behavior and biophysical systems to address practical challenges for the design of effective governance regimes (policy feedbacks) for highly uncertain natural resource systems.

Is dispersal neutral?

PubMed

Lowe, Winsor H; McPeek, Mark A

2014-08-01

Dispersal is difficult to quantify and often treated as purely stochastic and extrinsically controlled. Consequently, there remains uncertainty about how individual traits mediate dispersal and its ecological effects. Addressing this uncertainty is crucial for distinguishing neutral versus non-neutral drivers of community assembly. Neutral theory assumes that dispersal is stochastic and equivalent among species. This assumption can be rejected on principle, but common research approaches tacitly support the 'neutral dispersal' assumption. Theory and empirical evidence that dispersal traits are under selection should be broadly integrated in community-level research, stimulating greater scrutiny of this assumption. A tighter empirical connection between the ecological and evolutionary forces that shape dispersal will enable richer understanding of this fundamental process and its role in community assembly. Copyright © 2014 Elsevier Ltd. All rights reserved.

Environmental release of chemicals and reproductive ecology.

PubMed Central

Bajaj, J S; Misra, A; Rajalakshmi, M; Madan, R

1993-01-01

Reproductive ecology is defined as "the study of causes and mechanisms of the effects of environmental risk factors on reproductive health and the methods of their prevention and management." Major areas of concern, within the purview of this paper, relate to adverse pregnancy outcomes, effects on target tissues in the male and the female, and alterations in the control and regulatory mechanisms of reproductive processes. Teratogenic potential of chemicals, released as a result of accidents and catastrophes, is of critical significance. Congenital Minamata disease is due to transplacental fetal toxicity caused by accidental ingestion of methyl mercury. Generalized disorders of ectodermal tissue following prenatal exposure to polychlorinated biphenyls have been reported in Taiwan and Japan. The Bhopal gas disaster, a catastrophic industrial accident, was due to a leak of toxic gas, methyl isocyanate (MIC), in the pesticide manufacturing process. The outcome of pregnancy was studied in female survivors of MIC exposure. The spontaneous abortion rate was nearly four times more common in the affected areas as compared to the control area (24.2% versus 5.6%; p < 0.0001). Furthermore, while stillbirth rate was found to be similar in the affected and control areas, the perinatal and neonatal mortality rates were observed to be higher in the affected area. The rate of congenital malformations in the affected and control areas did not show any significant difference. Chromosomal aberrations and sister chromatid exchange (SCE) frequencies were investigated in human survivors of exposure. The observed SCE frequencies in control and exposed groups indicated that mutagenesis has been induced. Strategies for the management, prediction, and preventability of such disasters are outlined. PMID:8243381

Power of national economy, disease control and employment status in patients with RA-an analytical multi-site ecological study.

PubMed

Pieringer, Herwig; Puchner, Rudolf; Pohanka, Erich; Danninger, Kathrin

2016-02-01

In rheumatology, sufficient disease control is a central part of the treatment concept. However, modern treatment strategies are associated with a substantial economic burden for health care systems. Ecological studies offer the unique opportunity to analyse differences between groups as well as group level effects. In the present analytical multi-site ecological study, we investigated whether more powerful national economies as measured by the gross domestic product per capita (GDPpc) are associated with better disease control in RA patients as measured by the disease activity score 28 (DAS28). We used aggregated data on RA patients from the recently published COMORA study as well as the World Health Organization database. There was a strong negative correlation between DAS28 and GDPpc (r = -0.815; p = 0.0002). Adjustment for sex, smoking status, disease duration or current employment status did not significantly change this association. There was a strong, negative correlation between DAS28 and age (r = -0.870; p < 0.001) and a strong, positive correlation between GDPpc and age (r = 0.737; p = 0.002). Adjustment for age reduced the regression coefficient (DAS28/GDPpc) to -0.000018 (p = 0.054). There was a negative correlation between DAS28 and current employment status (r = -0.642; p = 0.008) and a positive correlation between GDPpc and employment status (r = 0.722; p = 0.002). In conclusion, there is evidence of an association between disease control and GDPpc. This association is alleviated after adjustment for age. Of note, in countries with higher GDPpc, a higher proportion of RA patients are currently employed. This is true despite the fact that RA patients in countries with higher GDPpc are also older.

Study on O2-supplying characteristics of Azolla in Controlled Ecological Life Support System

NASA Astrophysics Data System (ADS)

Chen, Min; Deng, Sufang; Yang, Youquang; Huang, Yibing; Liu, Zhongzhu

Azolla has high growth and propagation rate, strong photosynthetic O2-releasing ability and rich nutrient value. It is able to be used as salad-type vegetable, and can also be cultured on wet bed in multi-layer condition. Hence, it possesses a potential functioning as providing O2, fresh vegetable and absorbing CO2 for Controlled Ecological Life Support System in space. In this study, we try to make clear the O2-providing characteristics of Azolla in controlled close chamber under manned condition in order to lay a foundation for Azolla as a biological component in the next ground simulated experiment and space application. A closed test cham-ber of Controlled Ecological Life Support System and Azolla wet-culturing devices were built to measure the changes of atmospheric O2-CO2 concentration inside chamber under "Azolla-fish -men" coexisting condition. The results showed that, the amount of O2 consumption is 80.49 83.07 ml/h per kilogram fish, the amount of CO2 emissions is 70.49 73.56 ml/(kg • h); O2 consumption of trial volunteers is 19.71 L/h, the volume of respiration release CO2 18.90 L/h .Artificial light intensity of Azolla wet culture under 70009000 Lx, people respiration and Azolla photosynthesis complemented each other, the atmospheric O2-CO2 concentration inside chamber maintained equilibration. Elevated atmospheric CO2 concentrations in close chamber have obvious effects on enhancing Azolla net photosynthesis efficiency. This shows that Azolla has strong photosynthetic O2-releasing ability, which equilibrates the O2-CO2 concentration inside chamber in favor of human survival, and then verifies the prospect of Azolla in space application.

Archaeal and bacterial community analysis of several Yellowstone National Park hot springs

NASA Astrophysics Data System (ADS)

Colman, D. R.; Takacs-Vesbach, C. D.

2012-12-01

The hot springs of Yellowstone National Park (YNP) are home to a diverse assemblage of microorganisms. Culture-independent studies have significantly expanded our understanding of the diversity of both Bacteria and Archaea present in YNP springs as well as the geochemical and ecological controls on communities. While the ecological analysis of Bacteria among the physicochemically heterogenous springs of YNP has been previously conducted, less is known about the extent of diversity of Archaeal communities and the chemical and ecological controls on their populations. Here we report a culture-independent analysis of 31 hot spring archaeal and bacterial communities of YNP springs using next generation sequencing. We found the phylogenetic diversity of Archaea to be generally comparable to that of co-occurring bacterial communities although overall, in the springs we investigated, diversity was higher for Bacteria than Archaea. Chemical and physical controls were similar for both domains with pH correlating most strongly with community composition. Community differences reflected the partitioning of taxonomic groups in low or high pH springs for both domains. Results will be discussed in a geochemical and ecological context.

Assessing ecological risks to the fish community from residual coal fly ash in Watts Bar Reservoir, Tennessee

DOE PAGES

Rigg, David K.; Wacksman, Mitch N.; Iannuzzi, Jacqueline; ...

2014-12-18

For this research, extensive site-specific biological and environmental data were collected to support an evaluation of risks to the fish community in Watts Bar Reservoir from residual ash from the December 2008 Tennessee Valley Authority (TVA) Kingston ash release. This paper describes the approach used and results of the risk assessment for the fish community, which consists of multiple measurement endpoints (measures of exposure and effects) for fish. The lines of evidence included 1) comparing postspill annual fish community assessments with nearby prespill data and data from other TVA reservoirs, 2) evaluating possible effects of exposures of fish eggs andmore » larval fish to ash in controlled laboratory toxicity tests, 3) evaluating reproductive competence of field-exposed fish, 4) assessing individual fish health through physical examination, histopathology, and blood chemistry, 5) comparing fish tissue concentrations with literature-based critical body residues, and 6) comparing concentrations of ash-related contaminants in surface waters with US Environmental Protection Agency's (USEPA) Ambient Water Quality Standards for Fish and Aquatic Life. These measurement endpoints were treated as independent lines of evidence that were integrated into an overall weight-of-evidence estimate of risk to the fish community. Collectively, the data and analysis presented here indicate that ash and ash-related constituents pose negligible risks to the fish communities in Watts Bar Reservoir. This conclusion contradicts the predictions by some researchers immediately following the ash release of devastating effects on the aquatic ecology of Watts Bar Reservoir. The information presented in this article reaffirms the wisdom of carefully evaluating the evidence before predicting probable ecological effects of a major event such as the TVA Kingston ash release. Lastly, this study demonstrates that a thorough and detailed investigation using multiple measurement endpoints is needed to properly evaluate ecological effects.« less

Assessing ecological risks to the fish community from residual coal fly ash in Watts Bar Reservoir, Tennessee

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rigg, David K.; Wacksman, Mitch N.; Iannuzzi, Jacqueline

For this research, extensive site-specific biological and environmental data were collected to support an evaluation of risks to the fish community in Watts Bar Reservoir from residual ash from the December 2008 Tennessee Valley Authority (TVA) Kingston ash release. This paper describes the approach used and results of the risk assessment for the fish community, which consists of multiple measurement endpoints (measures of exposure and effects) for fish. The lines of evidence included 1) comparing postspill annual fish community assessments with nearby prespill data and data from other TVA reservoirs, 2) evaluating possible effects of exposures of fish eggs andmore » larval fish to ash in controlled laboratory toxicity tests, 3) evaluating reproductive competence of field-exposed fish, 4) assessing individual fish health through physical examination, histopathology, and blood chemistry, 5) comparing fish tissue concentrations with literature-based critical body residues, and 6) comparing concentrations of ash-related contaminants in surface waters with US Environmental Protection Agency's (USEPA) Ambient Water Quality Standards for Fish and Aquatic Life. These measurement endpoints were treated as independent lines of evidence that were integrated into an overall weight-of-evidence estimate of risk to the fish community. Collectively, the data and analysis presented here indicate that ash and ash-related constituents pose negligible risks to the fish communities in Watts Bar Reservoir. This conclusion contradicts the predictions by some researchers immediately following the ash release of devastating effects on the aquatic ecology of Watts Bar Reservoir. The information presented in this article reaffirms the wisdom of carefully evaluating the evidence before predicting probable ecological effects of a major event such as the TVA Kingston ash release. Lastly, this study demonstrates that a thorough and detailed investigation using multiple measurement endpoints is needed to properly evaluate ecological effects.« less

Linking manipulative experiments to field data to test the dilution effect.

PubMed

Venesky, Matthew D; Liu, Xuan; Sauer, Erin L; Rohr, Jason R

2014-05-01

The dilution effect, the hypothesis that biodiversity reduces disease risk, has received support in many systems. However, few dilution effect studies have linked mechanistic experiments to field patterns to establish both causality and ecological relevance. We conducted a series of laboratory experiments and tested the dilution effect hypothesis in an amphibian-Batrachochytrium dendrobatidis (Bd) system and tested for consistency between our laboratory experiments and field patterns of amphibian species richness, host identity and Bd prevalence. In our laboratory experiments, we show that tadpoles can filter feed Bd zoospores and that the degree of suspension feeding was positively associated with their dilution potential. The obligate suspension feeder, Gastrophryne carolinensis, generally diluted the risk of chytridiomycosis for tadpoles of Bufo terrestris and Hyla cinerea, whereas tadpoles of B. terrestris (an obligate benthos feeder) generally amplified infections for the other species. In addition, G. carolinensis reduced Bd abundance on H. cinerea more so in the presence than absence of B. terrestris and B. terrestris amplified Bd abundance on H. cinerea more so in the absence than presence of G. carolinensis. Also, when ignoring species identity, species richness was a significant negative predictor of Bd abundance. In our analysis of field data, the presence of Bufo spp. and Gastrophryne spp. were significant positive and negative predictors of Bd prevalence, respectively, even after controlling for climate, vegetation, anthropogenic factors (human footprint), species richness and sampling effort. These patterns of dilution and amplification supported our laboratory findings, demonstrating that the results are likely ecologically relevant. The results from our laboratory and field data support the dilution effect hypothesis and also suggest that dilution and amplification are predictable based on host traits. Our study is among the first to link manipulative experiments, in which a potential dilution mechanism is supported, with analyses of field data on species richness, host identity, spatial autocorrelation and disease prevalence. © 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society.

[Ecological suitability assessment and optimization of urban land expansion space in Guiyang City].

PubMed

Qiu, Cong-hao; Li, Yang-bing; Feng, Yuan-song

2015-09-01

Based on the case study of Guiyang City, the minimum cumulative resistance model integrating construction land source, ecological rigid constraints and ecological function type resistance factor, was built by use of cost-distance analysis of urban spatial expansion resistance value through ArcGIS 9.3 software in this paper. Then, the ecological resistance of city spatial expansion of Guiyang from 2010 was simulated dynamically and the ecological suitability classification of city spatial expansion was assessed. According to the conflict between the newly increased city construction land in 2014 and its ecological suitability, the unreasonable city land spatial allocation was discussed also. The results showed that the ecological suitability zonation and the city expansion in the study area were basically consistent during 2010-2014, but the conflict between the new city construction and its land ecological suitability was more serious. The ecological conflict area accounted for 58.2% of the new city construction sites, 35.4% of which happened in the ecological control area, 13.9% in the limited development area and 8.9% in the prohibition development area. The intensification of ecological land use conflict would impair the ecological service function and ecological safety, so this paper put forward the city spatial expansion optimal path to preserve the ecological land and improve the construction land space pattern of Guiyang City so as to ensure its ecological safety.

Associations between conservation practices and ecology: ecological responses of agricultural streams and lakes

USDA-ARS?s Scientific Manuscript database

The Conservation Effects Assessment Program (CEAP) Watershed Assessment Study goals are to quantify the environmental benefits of conservation practices at the watershed scale. Currently, a critical knowledge gap exists in linking conservation practices and their ecological effects on aquatic ecosy...

[Triatoma dimidiata in Colombia: Distribution, ecology and epidemiological importance].

PubMed

Quirós-Gómez, Óscar; Jaramillo, Nicolás; Angulo, Víctor; Parra-Henao, Gabriel

2017-06-01

Triatoma dimidiata is an important vector of Chagas disease in Central America and countries of northern South America. In Colombia, it has a wide geographical distribution with reported presence in 14 departments in the Andean, Caribbean, Eastern plains and Upper Magdalena regions, where it occupies different natural and artificial ecotopes. The species is considered a secondary vector in the transmission of Trypanosoma cruzi. Its presence in wild, peridomestic and intradomiciliary habitats in the Andean region, coupled with its ability to move between them, has allowed it to escape the control based on pyrethroids spraying, highlighting its importance in maintaining transmission of the parasite through the potential reinfestation of homes.Understanding the relation of T. dimidiata and its habitats, as well as the empowerment of communities, will contribute to the development of effective and lasting control systems.The purpose of this review was to describe the distribution, risk factors, ecology, entomological features and habitats of T. dimidiata populations in Colombia, and to propose alternative interventions in agreement with the specific characteristics of the species.

Concerning RNA-guided gene drives for the alteration of wild populations.

PubMed

Esvelt, Kevin M; Smidler, Andrea L; Catteruccia, Flaminia; Church, George M

2014-07-17

Gene drives may be capable of addressing ecological problems by altering entire populations of wild organisms, but their use has remained largely theoretical due to technical constraints. Here we consider the potential for RNA-guided gene drives based on the CRISPR nuclease Cas9 to serve as a general method for spreading altered traits through wild populations over many generations. We detail likely capabilities, discuss limitations, and provide novel precautionary strategies to control the spread of gene drives and reverse genomic changes. The ability to edit populations of sexual species would offer substantial benefits to humanity and the environment. For example, RNA-guided gene drives could potentially prevent the spread of disease, support agriculture by reversing pesticide and herbicide resistance in insects and weeds, and control damaging invasive species. However, the possibility of unwanted ecological effects and near-certainty of spread across political borders demand careful assessment of each potential application. We call for thoughtful, inclusive, and well-informed public discussions to explore the responsible use of this currently theoretical technology.

Evaluation of Ecological Environment Security in Contiguous Poverty Alleviation Area of Sichuan Province

NASA Astrophysics Data System (ADS)

Xian, W.; Chen, Y.; Chen, J.; Luo, X.; Shao, H.

2018-04-01

According to the overall requirements of ecological construction and environmental protection, rely on the national key ecological engineering, strengthen ecological environmental restoration and protection, improve forest cover, control soil erosion, construct important ecological security barrier in poor areas, inhibit poverty alleviation through ecological security in this area from environmental damage to the vicious cycle of poverty. Obviously, the dynamic monitoring of ecological security in contiguous destitute areas of Sichuan province has a policy sense of urgency and practical significance. This paper adopts RS technology and GIS technology to select the Luhe region of Jinchuan county and Ganzi prefecture as the research area, combined with the characteristics of ecological environment in poor areas, the impact factors of ecological environment are determined as land use type, terrain slope, vegetation cover, surface water, soil moisture and other factors. Using the ecological environmental safety assessment model, the ecological environment safety index is calculated. According to the index, the ecological environment safety of the research area is divided into four levels. The ecological environment safety classification map of 1990 in 2009 is obtained. It can be seen that with the human modern life and improve their economic level, the surrounding environment will be destroyed, because the research area ecological environment is now in good, the ecological environment generally tends to be stable. We should keep its ecological security good and improve local economic income. The relationship between ecological environmental security and economic coordinated development in poor areas has very important strategic significance.

Review of Pasteuria penetrans: Biology, Ecology, and Biological Control Potential.

PubMed

Chen, Z X; Dickson, D W

1998-09-01

Pasteuria penetrans is a mycelial, endospore-forming, bacterial parasite that has shown great potential as a biological control agent of root-knot nematodes. Considerable progress has been made during the last 10 years in understanding its biology and importance as an agent capable of effectively suppressing root-knot nematodes in field soil. The objective of this review is to summarize the current knowledge of the biology, ecology, and biological control potential of P. penetrans and other Pasteuria members. Pasteuria spp. are distributed worldwide and have been reported from 323 nematode species belonging to 116 genera of free-living, predatory, plant-parasitic, and entomopathogenic nematodes. Artificial cultivation of P. penetrans has met with limited success; large-scale production of endospores depends on in vivo cultivation. Temperature affects endospore attachment, germination, pathogenesis, and completion of the life cycle in the nematode pseudocoelom. The biological control potential of Pasteuria spp. have been demonstrated on 20 crops; host nematodes include Belonolaimus longicaudatus, Heterodera spp., Meloidogyne spp., and Xiphinema diversicaudatum. Pasteuria penetrans plays an important role in some suppressive soils. The efficacy of the bacterium as a biological control agent has been examined. Approximately 100,000 endospores/g of soil provided immediate control of the peanut root-knot nematode, whereas 1,000 and 5,000 endospores/g of soil each amplified in the host nematode and became suppressive after 3 years.

The impact of an environmental education program on children's and parents' knowledge, attitudes, motivation and behaviors

NASA Astrophysics Data System (ADS)

Legault, Louise M. R.

1999-11-01

Developments in the Quebec educational system enabled us to evaluate the impact of a new educational environmental program (EEP) on a group of children enrolled in this program for the first time (i.e., the experimental group). This EEP comprised a formal curriculum and environmental activities. A control group of children was enrolled in schools where environmental issues were confined to the natural sciences subject. The goals of this study were threefold. The first goal was to evaluate the impact of an EEP on children's and parents' ecological knowledge, attitudes, motivation, and behaviors. The second goal was to investigate if a motivational model of ecological behaviors observed in adult populations could be replicated with children. Part of this goal also included the comparison of path analyses results across experimental conditions, independently for children and parents. The third goal was to identify more clearly what specific children's characteristics influenced parents' ecological attitudes and motivation. Included in this goal was the investigation of possible differences in the strength of associations between constructs in paths analyses conducted in the experimental and control groups of parents. Results suggested that children in the experimental group were more likely to ask teachers and parents for ecological information and presented a more self-determined motivational profile. Additional analyses revealed that children enrolled in an EEP performed ecological behaviors less for extrinsic motives. Level of knowledge, other attitudes and behavioral measures did not differ significantly between the two groups. Parents of children in the experimental group reported lower levels of satisfaction towards the environment and were more likely to get information on ecological issues and strategies from children. No other significant differences between groups of parents were found. Path analyses results suggested that parents' perceptions of children's provision of autonomy support and of ecological information, as well as, joint child/parent involvement in ecological activities favored parents' ecological attitudes and motivation. These results were consistent across the experimental and the control groups. Future studies are necessary to identify optimal intervention strategies devised to foster in people a sense of personal responsibility and self-determination that may propel them into action.

Increasing self-regulatory energy using an Internet-based training application delivered by smartphone technology.

PubMed

Cranwell, Jo; Benford, Steve; Houghton, Robert J; Golembewski, Michael; Golembewksi, Michael; Fischer, Joel E; Hagger, Martin S

2014-03-01

Self-control resources can be defined in terms of "energy." Repeated attempts to override desires and impulses can result in a state of reduced self-control energy termed "ego depletion" leading to a reduced capacity to regulate future self-control behaviors effectively. Regular practice or "training" on self-control tasks may improve an individual's capacity to overcome ego depletion effectively. The current research tested the effectiveness of training using a novel Internet-based smartphone application to improve self-control and reduce ego depletion. In two experiments, participants were randomly assigned to either an experimental group, which received a daily program of self-control training using a modified Stroop-task Internet-based application delivered via smartphone to participants over a 4-week period, or a no-training control group. Participants assigned to the experimental group performed significantly better on post-training laboratory self-control tasks relative to participants in the control group. Findings support the hypothesized training effect on self-control and highlight the effectiveness of a novel Internet-based application delivered by smartphone as a practical means to administer and monitor a self-control training program. The smartphone training application has considerable advantages over other means to train self-control adopted in previous studies in that it has increased ecological validity and enables effective monitoring of compliance with the training program.

Increasing Self-Regulatory Energy Using an Internet-Based Training Application Delivered by Smartphone Technology

PubMed Central

Benford, Steve; Houghton, Robert J.; Golembewksi, Michael; Fischer, Joel E.; Hagger, Martin S.

2014-01-01

Abstract Self-control resources can be defined in terms of “energy.” Repeated attempts to override desires and impulses can result in a state of reduced self-control energy termed “ego depletion” leading to a reduced capacity to regulate future self-control behaviors effectively. Regular practice or “training” on self-control tasks may improve an individual's capacity to overcome ego depletion effectively. The current research tested the effectiveness of training using a novel Internet-based smartphone application to improve self-control and reduce ego depletion. In two experiments, participants were randomly assigned to either an experimental group, which received a daily program of self-control training using a modified Stroop-task Internet-based application delivered via smartphone to participants over a 4-week period, or a no-training control group. Participants assigned to the experimental group performed significantly better on post-training laboratory self-control tasks relative to participants in the control group. Findings support the hypothesized training effect on self-control and highlight the effectiveness of a novel Internet-based application delivered by smartphone as a practical means to administer and monitor a self-control training program. The smartphone training application has considerable advantages over other means to train self-control adopted in previous studies in that it has increased ecological validity and enables effective monitoring of compliance with the training program. PMID:24015984

Ecological and health risk-based characterization of agricultural soils contaminated with polycyclic aromatic hydrocarbons in the vicinity of a chemical plant in China.

PubMed

Liu, Geng; Niu, Junjie; Guo, Wenjiong; An, Xiangsheng; Zhao, Long

2016-11-01

Polycyclic aromatic hydrocarbons (PAHs) from chemical plants can cause serious pollution of surrounding agricultural soils. A comprehensive study of agricultural soils was conducted in the vicinity of a chemical plant in China to characterize the soil PAH concentration, as well as their composition and sources. Human health and a screening-level ecological risk assessment were conducted for PAH contamination in agricultural soils. The results showed that the total concentrations of 16 priority PAHs ranged from 250.49 to 9387.26 ng g(-1), with an average of 2780.42 ng g(-1). High molecular weight PAHs (four to six rings) were the dominant component, accounting for more than 60% of all PAHs. Principal component analysis (PCA) and positive matrix factorization model (PMF) suggested that diesel emissions, coal combustion, coke ovens, and fuel combustion and gasoline emissions were the main sources of PAHs in agricultural soils. The ecological risk assessment results based on the effects range-low (ERL), the effects range-median (ERM), and the ecological screening levels (ESL) indicated that the exposure to ∑PAH16 was >ERL, >ERM, and ≥ERL and ESL at 78.1% of the soil sampling stations, and could induce biological effects in mammals. The Bapeq concentrations posed a potential carcinogenic risk to humans. Further risk management and control of soil PAHs in these agricultural soils is required to ensure the safety of the biocoenosis and human health. Copyright © 2016 Elsevier Ltd. All rights reserved.

A Tale of Four Stories: Soil Ecology, Theory, Evolution and the Publication System

PubMed Central

Barot, Sébastien; Blouin, Manuel; Fontaine, Sébastien; Jouquet, Pascal; Lata, Jean-Christophe; Mathieu, Jérôme

2007-01-01

Background Soil ecology has produced a huge corpus of results on relations between soil organisms, ecosystem processes controlled by these organisms and links between belowground and aboveground processes. However, some soil scientists think that soil ecology is short of modelling and evolutionary approaches and has developed too independently from general ecology. We have tested quantitatively these hypotheses through a bibliographic study (about 23000 articles) comparing soil ecology journals, generalist ecology journals, evolutionary ecology journals and theoretical ecology journals. Findings We have shown that soil ecology is not well represented in generalist ecology journals and that soil ecologists poorly use modelling and evolutionary approaches. Moreover, the articles published by a typical soil ecology journal (Soil Biology and Biochemistry) are cited by and cite low percentages of articles published in generalist ecology journals, evolutionary ecology journals and theoretical ecology journals. Conclusion This confirms our hypotheses and suggests that soil ecology would benefit from an effort towards modelling and evolutionary approaches. This effort should promote the building of a general conceptual framework for soil ecology and bridges between soil ecology and general ecology. We give some historical reasons for the parsimonious use of modelling and evolutionary approaches by soil ecologists. We finally suggest that a publication system that classifies journals according to their Impact Factors and their level of generality is probably inadequate to integrate “particularity” (empirical observations) and “generality” (general theories), which is the goal of all natural sciences. Such a system might also be particularly detrimental to the development of a science such as ecology that is intrinsically multidisciplinary. PMID:18043755

Ecological and Evolutionary Effects of Stickleback on Community Structure

PubMed Central

Des Roches, Simone; Shurin, Jonathan B.; Schluter, Dolph; Harmon, Luke J.

2013-01-01

Species’ ecology and evolution can have strong effects on communities. Both may change concurrently when species colonize a new ecosystem. We know little, however, about the combined effects of ecological and evolutionary change on community structure. We simultaneously examined the effects of top-predator ecology and evolution on freshwater community parameters using recently evolved generalist and specialist ecotypes of three-spine stickleback (Gasterosteus aculeatus). We used a mesocosm experiment to directly examine the effects of ecological (fish presence and density) and evolutionary (phenotypic diversity and specialization) factors on community structure at lower trophic levels. We evaluated zooplankton biomass and composition, periphyton and phytoplankton chlorophyll-a concentration, and net primary production among treatments containing different densities and diversities of stickleback. Our results showed that both ecological and evolutionary differences in the top-predator affect different aspects of community structure and composition. Community structure, specifically the abundance of organisms at each trophic level, was affected by stickleback presence and density, whereas composition of zooplankton was influenced by stickleback diversity and specialization. Primary productivity, in terms of chlorophyll-a concentration and net primary production was affected by ecological but not evolutionary factors. Our results stress the importance of concurrently evaluating both changes in density and phenotypic diversity on the structure and composition of communities. PMID:23573203

Environmental risk assessment of a genetically-engineered microorganism: Erwinia carotovora

DOE Office of Scientific and Technical Information (OSTI.GOV)

Orvos, D.R.

1989-01-01

Environmental use of genetically-engineered microorganisms (GEMs) has raised concerns over potential ecological impact. Development of microcosm systems useful in preliminary testing for risk assessment will provide useful information for predicting potential structural, functional, and genetic effects of GEM release. This study was executed to develop techniques that may be useful in risk assessment and microbial ecology, to ascertain which parameters are useful in determining risk and to predict risk from releasing an engineered strain of Erwinia carotovora. A terrestrial microcosm system for use in GEM risk assessment studies was developed for use in assessing alterations of microbial structure and functionmore » that may be caused by introducing the engineered strain of E. carotovora. This strain is being developed for use as a biological control agent for plant soft rot. Parameters that were monitored included survival and intraspecific competition of E. carotovora, structural effects upon both total bacterial populations and numbers of selected bacterial genera, effects upon activities of dehydrogenase and alkaline phosphatase, effects upon soil nutrients, and potential for gene transfer into or out of the engineered strain.« less

Population ecology of the sea lamprey (Petromyzon marinus) as an invasive species in the Laurentian Great Lakes and an imperiled species in Europe

USGS Publications Warehouse

Hansen, Michael J.; Madenjian, Charles P.; Slade, Jeffrey W.; Steeves, Todd B.; Almeida, Pedro R.; Quintella, Bernardo R.

2016-01-01

The sea lamprey Petromyzon marinus (Linnaeus) is both an invasive non-native species in the Laurentian Great Lakes of North America and an imperiled species in much of its native range in North America and Europe. To compare and contrast how understanding of population ecology is useful for control programs in the Great Lakes and restoration programs in Europe, we review current understanding of the population ecology of the sea lamprey in its native and introduced range. Some attributes of sea lamprey population ecology are particularly useful for both control programs in the Great Lakes and restoration programs in the native range. First, traps within fish ladders are beneficial for removing sea lampreys in Great Lakes streams and passing sea lampreys in the native range. Second, attractants and repellants are suitable for luring sea lampreys into traps for control in the Great Lakes and guiding sea lamprey passage for conservation in the native range. Third, assessment methods used for targeting sea lamprey control in the Great Lakes are useful for targeting habitat protection in the native range. Last, assessment methods used to quantify numbers of all life stages of sea lampreys would be appropriate for measuring success of control in the Great Lakes and success of conservation in the native range.

A METHOD TO INCORPORATE ECOLOGY INTO RESIDENCE TIME OF CHEMICALS IN EMBAYMENTS: LOCAL EFFECT TIME

EPA Science Inventory

Residence times are classically defined by the physical and chemical aspects of water bodies rather than by their ecological implications. Therefore, a more clear and direct connection between the residence times and ecological effects is necessary to quantitatively relate these ...

Use of QSARs in international decision-making frameworks to predict ecologic effects and environmental fate of chemical substances.

PubMed Central

Cronin, Mark T D; Walker, John D; Jaworska, Joanna S; Comber, Michael H I; Watts, Christopher D; Worth, Andrew P

2003-01-01

This article is a review of the use, by regulatory agencies and authorities, of quantitative structure-activity relationships (QSARs) to predict ecologic effects and environmental fate of chemicals. For many years, the U.S. Environmental Protection Agency has been the most prominent regulatory agency using QSARs to predict the ecologic effects and environmental fate of chemicals. However, as increasing numbers of standard QSAR methods are developed and validated to predict ecologic effects and environmental fate of chemicals, it is anticipated that more regulatory agencies and authorities will find them to be acceptable alternatives to chemical testing. PMID:12896861

Study on ecological regulation of coastal plain sluice

NASA Astrophysics Data System (ADS)

Yu, Wengong; Geng, Bing; Yu, Huanfei; Yu, Hongbo

2018-02-01

Coastal plains are densely populated and economically developed, therefore their importance is self-evident. However, there are some problems related with water in coastal plains, such as low flood control capacity and severe water pollution. Due to complicated river network hydrodynamic force, changeable flow direction and uncertain flood concentration and propagation mechanism, it is rather difficult to use sluice scheduling to realize flood control and tackle water pollution. On the base of the measured hydrological data during once-in-a-century Fitow typhoon in 2013 in Yuyao city, by typical analysis, theoretical analysis and process simulation, some key technologies were researched systematically including plain river network sluice ecological scheduling, “one tide” flood control and drainage scheduling and ecological running water scheduling. In the end, single factor health diagnostic evaluation, unit hydrograph of plain water level and evening tide scheduling were put forward.

Observational studies and the difficult quest for causality: lessons from vaccine effectiveness and impact studies.

PubMed

Lipsitch, Marc; Jha, Ayan; Simonsen, Lone

2016-12-01

Although randomized placebo-controlled trials (RCT) are critical to establish efficacy of vaccines at the time of licensure, important remaining questions about vaccine effectiveness (VE)-used here to include individual-level measures and population-wide impact of vaccine programmes-can only be answered once the vaccine is in use, from observational studies. However, such studies are inherently at risk for bias. Using a causal framework and illustrating with examples, we review newer approaches to detecting and avoiding confounding and selection bias in three major classes of observational study design: cohort, case-control and ecological studies. Studies of influenza VE, especially in seniors, are an excellent demonstration of the challenges of detecting and reducing such bias, and so we use influenza VE as a running example. We take a fresh look at the time-trend studies often dismissed as 'ecological'. Such designs are the only observational study design that can measure the overall effect of a vaccination programme [indirect (herd) as well as direct effects], and are in fact already an important part of the evidence base for several vaccines currently in use. Despite the great strides towards more robust observational study designs, challenges lie ahead for evaluating best practices for achieving robust unbiased results from observational studies. This is critical for evaluation of national and global vaccine programme effectiveness. © The Author 2016; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.

River networks as ecological corridors: A coherent ecohydrological perspective

NASA Astrophysics Data System (ADS)

Rinaldo, Andrea; Gatto, Marino; Rodriguez-Iturbe, Ignacio

2018-02-01

This paper draws together several lines of argument to suggest that an ecohydrological framework, i.e. laboratory, field and theoretical approaches focused on hydrologic controls on biota, has contributed substantially to our understanding of the function of river networks as ecological corridors. Such function proves relevant to: the spatial ecology of species; population dynamics and biological invasions; the spread of waterborne disease. As examples, we describe metacommunity predictions of fish diversity patterns in the Mississippi-Missouri basin, geomorphic controls imposed by the fluvial landscape on elevational gradients of species' richness, the zebra mussel invasion of the same Mississippi-Missouri river system, and the spread of proliferative kidney disease in salmonid fish. We conclude that spatial descriptions of ecological processes in the fluvial landscape, constrained by their specific hydrologic and ecological dynamics and by the ecosystem matrix for interactions, i.e. the directional dispersal embedded in fluvial and host/pathogen mobility networks, have already produced a remarkably broad range of significant results. Notable scientific and practical perspectives are thus open, in the authors' view, to future developments in ecohydrologic research.

Cascading effects of artificial light at night: resource-mediated control of herbivores in a grassland ecosystem

PubMed Central

Bennie, Jonathan; Davies, Thomas W.; Cruse, David; Inger, Richard; Gaston, Kevin J.

2015-01-01

Artificial light at night has a wide range of biological effects on both plants and animals. Here, we review mechanisms by which artificial light at night may restructure ecological communities by modifying the interactions between species. Such mechanisms may be top-down (predator, parasite or grazer controlled), bottom-up (resource-controlled) or involve non-trophic processes, such as pollination, seed dispersal or competition. We present results from an experiment investigating both top-down and bottom-up effects of artificial light at night on the population density of pea aphids Acyrthosiphon pisum in a diverse artificial grassland community in the presence and absence of predators and under low-level light of different spectral composition. We found no evidence for top-down control of A. pisum in this system, but did find evidence for bottom-up effects mediated through the impact of light on flower head density in a leguminous food plant. These results suggest that physiological effects of light on a plant species within a diverse plant community can have detectable demographic effects on a specialist herbivore. PMID:25780243

Ostracism Online: A social media ostracism paradigm.

PubMed

Wolf, Wouter; Levordashka, Ana; Ruff, Johanna R; Kraaijeveld, Steven; Lueckmann, Jan-Matthis; Williams, Kipling D

2015-06-01

We describe Ostracism Online, a novel, social media-based ostracism paradigm designed to (1) keep social interaction experimentally controlled, (2) provide researchers with the flexibility to manipulate the properties of the social situation to fit their research purposes, (3) be suitable for online data collection, (4) be convenient for studying subsequent within-group behavior, and (5) be ecologically valid. After collecting data online, we compared the Ostracism Online paradigm with the Cyberball paradigm (Williams & Jarvis Behavior Research Methods, 38, 174-180, 2006) on need-threat and mood questionnaire scores (van Beest & Williams Journal of Personality and Social Psychology 91, 918-928, 2006). We also examined whether ostracized targets of either paradigm would be more likely to conform to their group members than if they had been included. Using a Bayesian analysis of variance to examine the individual effects of the different paradigms and to compare these effects across paradigms, we found analogous effects on need-threat and mood. Perhaps because we examined conformity to the ostracizers (rather than neutral sources), neither paradigm showed effects of ostracism on conformity. We conclude that Ostracism Online is a cost-effective, easy to use, and ecologically valid research tool for studying the psychological and behavioral effects of ostracism.

Controlled ecological life support system higher plant flight experiments

NASA Technical Reports Server (NTRS)

Tibbitts, T. W.; Wheeler, R. M.

1984-01-01

Requirements for spaceflight experments which involve higher plants were determined. The plants are studied for use in controlled ecological life support systems (CELSS). Two categories of research requirements are discussed: (1) the physical needs which include nutrient, water and gas exchange requirements; (2) the biological and physiological functions which affect plants in zero gravity environments. Physical problems studies are given the priority since they affect all biological experiments.

Evaluation of engineering foods for Controlled Ecological Life Support Systems (CELSS)

NASA Technical Reports Server (NTRS)

Karel, M.

1982-01-01

The feasibility of developing acceptable and reliable engineered foods for use in controlled ecological support systems (CELSS) was evaluated. Food resupply and regeneration are calculated, flow charts of food processes in a multipurpose food pilot plant are presented, and equipment for a multipurpose food pilot plant and potential simplification of processes are discussed. Food-waste treatment and water usage in food processing and preparation are also considered.

Nutrition and food technology for a Controlled Ecological Life Support System (CELSS)

NASA Technical Reports Server (NTRS)

Glaser, P. E.; Mabel, J. A.

1981-01-01

Food technology requirements and a nutritional strategy for a Controlled Ecological Life Support System (CELSS) to provide adequate food in an acceptable form in future space missions are discussed. The establishment of nutritional requirements, dietary goals, and a food service system to deliver acceptable foods in a safe and healthy form and the development of research goals and priorities were the main objectives of the study.

Ecological and Control Techniques for Sand Flies (Diptera: Psychodidae) Associated with Rodent Reservoirs of Leishmaniasis

DTIC Science & Technology

2013-09-12

found naturally in plant and animal tissues was highly effective for linking adult sand flies with their larval diet , without having to locate or capture...tissues was highly effective for linking adult sand flies with their larval diet , without having to locate or capture the sand fly larvae themselves. In a...overall adult population of sand flies in an area. However, indirect methods have been used to identify the diets of larvae of other insects through

The plant pathology of native plant restoration

USDA-ARS?s Scientific Manuscript database

Restoration of ecologically degraded sites will benefit from the convergence of knowledge drawn from such disparate and often compartmentalized (and heretofore not widely considered) areas of research as soil microbial ecology, plant pathology and agronomy. Restoration following biological control w...

Agricultural applications of insect ecological genomics

USDA-ARS?s Scientific Manuscript database

Agricultural entomology is poised to benefit from the application of ecological genomics, in particular the fields of biofuels generation and pest insect control. Metagenomic methods can characterize microbial communities of termites, wood-boring beetles and other insects, and transcriptomic approa...

[Delineation of urban development boundary based on the combination of rigidity and elasti-city: A case of Yiwu City in Zhejiang Province, China.

PubMed

Qiu, Si Qi; Yue, Wen Ze

2018-05-01

Under the background of rapid urbanization, we took the contradiction between the rapid urbanization and resource environment protection as the starting point, conducted some theoretical research on urban growth boundary. Based on the definition of urban development boundary, we took Yiwu City, Zhejiang Province as a typical instance. Firstly, this study delimited the ecological boundary as ecological basic constraint area, using the methods of ecological red line discrimination and ecological sensitivity evaluation. Furthermore, the MCE-CA model was used in simulating the city size in 2020, making some adjustments to the moderate and low ecological-sensitive areas in the eco-sensitivity assessing, and delimiting the size of urban growth boundary and elastic control zones. The results showed that the ecological constraint area with a total area of385.2 km 2 and outside of the ecological boundary was the security line of urban development and construction. The urban growth boundary with a total area of 163.3 km 2 was not only the spatial boundary that could be constructed now, but also could meet the future development and construction. The district between the ecological boundary and urban growth boundary was an elastic control zone, in which urban development activities were allowed, but the size of construction could not exceed 8.5% of the total urban development boundary area. Our results delimited the urban development boundary under the rigidity and elasticity, which could guide the urban space development and provide a theoretical reference for China.

An Ecological Momentary Intervention for weight loss and healthy eating via smartphone and Internet: study protocol for a randomised controlled trial.

PubMed

Boh, Bastiaan; Lemmens, Lotte H J M; Jansen, Anita; Nederkoorn, Chantal; Kerkhofs, Vincent; Spanakis, Gerasimos; Weiss, Gerhard; Roefs, Anne

2016-03-22

Long-term weight loss maintenance is difficult to achieve. Effectiveness of obesity interventions could be increased by providing extended treatment, and by focusing on person-environment interactions. Ecological Momentary Intervention (EMI) can account for these two factors by allowing an indefinite extension of a treatment protocol in everyday life. EMI relies on observations in daily life to intervene by providing appropriate in-the-moment treatment. The Think Slim intervention is an EMI based on the principles of cognitive behavioural therapy (CBT), and its effectiveness will be investigated in the current study. A randomised controlled trial (RCT) will be conducted. At least 134 overweight adults (body mass index (BMI) above 25 kg/m(2)) will be randomly assigned to an 8-week immediate intervention group (Diet + Think Slim intervention, n = 67) or to an 8-week diet-only control group (followed by the Think Slim intervention, n = 67). The Think Slim intervention consists of (1) an app-based EMI that estimates and intervenes when people are likely to overeat, based on Ecological Momentary Assessment data, and (2) ten online computerised CBT sessions which work in conjunction with an EMI module in the app. The primary outcome is BMI. Secondary outcomes include (1) scores on self-report questionnaires for dysfunctional thinking, eating styles, eating disorder pathology, general psychological symptomatology, and self-esteem, and (2) eating patterns, investigated via network analysis. Primary and secondary outcomes will be obtained at pre- and post-intervention measurements, and at 3- and 12-month follow-up measurements. This is the first EMI aimed at treating obesity via a cognitive approach, provided via a smartphone app and the Internet, in the context of an RCT. This trial has been registered at the Netherlands Trial Register, part of the Dutch Cochrane Centre ( NTR5473 ; registration date: 26 October 2015).

Modeling Disease Vector Occurrence When Detection Is Imperfect II: Drivers of Site-Occupancy by Synanthropic Triatoma brasiliensis in the Brazilian Northeast

PubMed Central

Valença-Barbosa, Carolina; Lima, Marli M.; Sarquis, Otília; Bezerra, Claudia M.; Abad-Franch, Fernando

2014-01-01

Background Understanding the drivers of habitat selection by insect disease vectors is instrumental to the design and operation of rational control-surveillance systems. One pervasive yet often overlooked drawback of vector studies is that detection failures result in some sites being misclassified as uninfested; naïve infestation indices are therefore biased, and this can confound our view of vector habitat preferences. Here, we present an initial attempt at applying methods that explicitly account for imperfect detection to investigate the ecology of Chagas disease vectors in man-made environments. Methodology We combined triplicate-sampling of individual ecotopes (n = 203) and site-occupancy models (SOMs) to test a suite of pre-specified hypotheses about habitat selection by Triatoma brasiliensis. SOM results were compared with those of standard generalized linear models (GLMs) that assume perfect detection even with single bug-searches. Principal Findings Triatoma brasiliensis was strongly associated with key hosts (native rodents, goats/sheep and, to a lesser extent, fowl) in peridomestic environments; ecotope structure had, in comparison, small to negligible effects, although wooden ecotopes were slightly preferred. We found evidence of dwelling-level aggregation of infestation foci; when there was one such focus, same-dwelling ecotopes, whether houses or peridomestic structures, were more likely to become infested too. GLMs yielded negatively-biased covariate effect estimates and standard errors; both were, on average, about four times smaller than those derived from SOMs. Conclusions/Significance Our results confirm substantial population-level ecological heterogeneity in T. brasiliensis. They also suggest that, at least in some sites, control of this species may benefit from peridomestic rodent control and changes in goat/sheep husbandry practices. Finally, our comparative analyses highlight the importance of accounting for the various sources of uncertainty inherent to vector studies, including imperfect detection. We anticipate that future research on infectious disease ecology will increasingly rely on approaches akin to those described here. PMID:24811125

Operation and Maintence, Vermilion Harbor, Erie County, Ohio.

DTIC Science & Technology

1976-03-01

channel and structural maintenance activities at Vermilion Harbor. Although 6 ...- this alternative would eliminate temporary adverse ecological effects of...of dredging on water quality, aquatic ecology , and harbor recreation and related 4 businesses wbuld be reduced to a level commensurate with reduced...effects on aquatic ecology but would have long- term, beneficial effects on shoreline erosion and beach areas. There have been no specific requests from

The Invisible and Indeterminable Value of Ecology: From Malaria Control to Ecological Research in the American South.

PubMed

Way, Albert G

2015-06-01

This essay tells the story of the Emory University Field Station, a malaria research station in southwest Georgia that operated from 1939 to 1958. Using the tools of environmental history and the history of science, it examines the station's founding, its fieldwork, and its place within the broader history of malaria control, eradication, and research. A joint effort of Emory University, the U.S. Public Health Service, and the Communicable Disease Center (CDC), this station was closely aligned with a broader movement of ideas about tropical diseases across the globe, but it also offers a case study of how science in the field can veer from mainstream thinking and official policy. As the CDC and other disease-fighting organizations were moving toward a global strategy of malaria eradication through the use of DDT, the Emory Field Station developed a postsanitarian approach to malaria. Drawing on resistance among American conservationists to environmental transformation in the name of malaria control, the station's staff embraced the science and worldview of ecology in an effort to lighten public health's hand on the land and to link human health to the environment in innovative, if sometimes opaque, ways. This essay, then, argues that the Emory Field Station represents an early confluence of ecology with the biomedical sciences, something very similar to what is now the important discipline of disease ecology.

Environmental radon exposure and childhood leukemia.

PubMed

Tong, Jian; Qin, Liqiang; Cao, Yi; Li, Jianxiang; Zhang, Jie; Nie, Jihua; An, Yan

2012-01-01

Despite the fact that animal and human epidemiological studies confirmed a link between radon exposure in homes and increased risk of lung cancer in general population, other types of cancers induced by radon, such as leukemia, have not been consistently demonstrated. The aim of this review was to summarize data published thus far from ecological and case-control studies in exposed populations, taking into account radon dose estimation and evidence of radon-induced genotoxicity, in an effort to clarify the correlation between home radon exposure and incidence of childhood leukemia. Among 12 ecological studies, 11 reported a positive association between radon levels and elevated frequency of childhood leukemia, with 8 being significant. In conjunction with ecological studies, several case-control studies on indoor radon exposure and childhood leukemia were examined, and most investigations indicated a weak association with only a few showing significance. A major source of uncertainty in radon risk assessment is radon dose estimate. Methods for radon exposure measurement in homes of children are one of the factors that affect the risk estimates in a case-control study. The effects of radon-induced genetic damage were studied both in vitro and in vivo using genetic endpoints including chromosomal aberration (CA), micronuclei (MN) formation, gene mutation, and deletions and insertions. By applying a meta-analysis, an increased risk of childhood leukemia induced by indoor radon exposure was noted for overall leukemia and for acute lymphoblastic leukemia (ALL). Data thus indicated an association between environmental radon exposure and elevated leukemia incidence, but more evidence is required in both human investigations and animal mechanistic research before this assumption may be confirmed with certainty.

Cooking "shrimp à la créole": a pilot study of an ecological rehabilitation in semantic dementia.

PubMed

Bier, Nathalie; Macoir, Joël; Joubert, Sven; Bottari, Carolina; Chayer, Céline; Pigot, Hélène; Giroux, Sylvain

2011-08-01

New learning in semantic dementia (SD) seems to be tied to a specific temporal and spatial context. Thus, cognitive rehabilitation could capitalise upon preserved episodic memory and focus on everyday activities which, once learned, will have an impact in everyday life. This pilot study thus explores the effectiveness of an ecological approach in one patient suffering from SD. EC, a 68-year-old woman with SD, stopped cooking complex meals due to a substantial loss of knowledge related to all food types. The therapy consisted of preparing a target recipe. She was asked to generate semantic attributes of ingredients found in one target, one control and two no-therapy recipes. The number of recipes cooked by EC between therapy sessions was computed. She was also asked to prepare a generalisation recipe combining ingredients from the target and control recipes. EC's generated semantic attributes (GSA) of ingredients pertaining to the target and control recipes increased significantly (p < .001), compared to the no-therapy recipes (ps > .79). The proportion of meals cooked also increased significantly (p = .021). For the generalisation recipe, she could not succeed without assistance. Frequent food preparation may have provided EC with new memories about the context, usage and appearance of some concepts. These memories seem very context-bound, but EC nonetheless re-introduced some recipes into her day-to-day life. The impact of these results on the relationship between semantic, episodic and procedural memory is discussed, as well as the relevance of an ecological approach in SD.

Modes, hydrodynamic processes and ecological impacts exerted by river-groundwater transformation in Junggar Basin, China

NASA Astrophysics Data System (ADS)

Wang, Wenke; Wang, Zhan; Hou, Rongzhe; Guan, Longyao; Dang, Yan; Zhang, Zaiyong; Wang, Hao; Duan, Lei; Wang, Zhoufeng

2018-05-01

The hydrodynamic processes and impacts exerted by river-groundwater transformation need to be studied at regional and catchment scale, especially with respect to diverse geology and lithology. This work adopted an integrated method to study four typical modes (characterized primarily by lithology, flow subsystems, and gaining/losing river status) and the associated hydrodynamic processes and ecological impacts in the southern part of Junggar Basin, China. River-groundwater transformation occurs one to four times along the basin route. For mode classification, such transformation occurs: once or twice, controlled by lithological factors (mode 1); twice, impacted by geomorphic features and lithological structures (mode 2); and three or four times, controlled by both geological and lithological structures (modes 3 and 4). Results also suggest: (1) there exist local and regional groundwater flow subsystems at 400 m depth, which form a multistage nested groundwater flow system. The groundwater flow velocities are 0.1-1.0 and <0.1 m/day for each of two subsystems; (2) the primary groundwater hydro-chemical type takes on apparent horizontal and vertical zoning characteristics, and the TDS of the groundwater evidently increases along the direction of groundwater flow, driven by hydrodynamic processes; (3) the streams, wetland and terminal lakes are the end-points of the local and regional groundwater flow systems. This work indicates that not only are groundwater and river water derived from the same source, but also hydrodynamic and hydro-chemical processes and ecological effects, as a whole in arid areas, are controlled by stream-groundwater transformation.

Seafood prices reveal impacts of a major ecological disturbance

PubMed Central

Smith, Martin D.; Oglend, Atle; Kirkpatrick, A. Justin; Asche, Frank; Bennear, Lori S.; Craig, J. Kevin; Nance, James M.

2017-01-01

Coastal hypoxia (dissolved oxygen ≤ 2 mg/L) is a growing problem worldwide that threatens marine ecosystem services, but little is known about economic effects on fisheries. Here, we provide evidence that hypoxia causes economic impacts on a major fishery. Ecological studies of hypoxia and marine fauna suggest multiple mechanisms through which hypoxia can skew a population’s size distribution toward smaller individuals. These mechanisms produce sharp predictions about changes in seafood markets. Hypoxia is hypothesized to decrease the quantity of large shrimp relative to small shrimp and increase the price of large shrimp relative to small shrimp. We test these hypotheses using time series of size-based prices. Naive quantity-based models using treatment/control comparisons in hypoxic and nonhypoxic areas produce null results, but we find strong evidence of the hypothesized effects in the relative prices: Hypoxia increases the relative price of large shrimp compared with small shrimp. The effects of fuel prices provide supporting evidence. Empirical models of fishing effort and bioeconomic simulations explain why quantifying effects of hypoxia on fisheries using quantity data has been inconclusive. Specifically, spatial-dynamic feedbacks across the natural system (the fish stock) and human system (the mobile fishing fleet) confound “treated” and “control” areas. Consequently, analyses of price data, which rely on a market counterfactual, are able to reveal effects of the ecological disturbance that are obscured in quantity data. Our results are an important step toward quantifying the economic value of reduced upstream nutrient loading in the Mississippi Basin and are broadly applicable to other coupled human-natural systems. PMID:28137850

A mixed model for the relationship between climate and human cranial form.

PubMed

Katz, David C; Grote, Mark N; Weaver, Timothy D

2016-08-01

We expand upon a multivariate mixed model from quantitative genetics in order to estimate the magnitude of climate effects in a global sample of recent human crania. In humans, genetic distances are correlated with distances based on cranial form, suggesting that population structure influences both genetic and quantitative trait variation. Studies controlling for this structure have demonstrated significant underlying associations of cranial distances with ecological distances derived from climate variables. However, to assess the biological importance of an ecological predictor, estimates of effect size and uncertainty in the original units of measurement are clearly preferable to significance claims based on units of distance. Unfortunately, the magnitudes of ecological effects are difficult to obtain with distance-based methods, while models that produce estimates of effect size generally do not scale to high-dimensional data like cranial shape and form. Using recent innovations that extend quantitative genetics mixed models to highly multivariate observations, we estimate morphological effects associated with a climate predictor for a subset of the Howells craniometric dataset. Several measurements, particularly those associated with cranial vault breadth, show a substantial linear association with climate, and the multivariate model incorporating a climate predictor is preferred in model comparison. Previous studies demonstrated the existence of a relationship between climate and cranial form. The mixed model quantifies this relationship concretely. Evolutionary questions that require population structure and phylogeny to be disentangled from potential drivers of selection may be particularly well addressed by mixed models. Am J Phys Anthropol 160:593-603, 2016. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

The effectiveness of vegetation management practices for prevention and control of bark beetle infestations in coniferous forests of the western and southern United States

Treesearch

Christopher J. Fettig; Kier D. Klepzig; Ronald f. Billings; A. Steven Munson; T. Evan Nebeker; Jose F. Negron; John T. Nowak

2007-01-01

Insects are major components of forest ecosystems, representing most of the biological diversity and affecting virtually all processes and uses. In the USA, bark beetles (Coleoptera: Curculionidae, Scolytinae) heavily influence the structure and function of these ecosystems by regulating certain aspects of primary production, nutrient cycling, ecological succession and...

A comparison of soil organic carbon stocks between residential turf grass and native soil

Treesearch

Richard V. Pouyat; Ian D. Yesilonis; Nancy E. Golubiewski

2009-01-01

A central principle in urban ecological theory implies that in urbanized landscapes anthropogenic drivers will dominate natural drivers in the control of soil organic carbon storage (SOC). To assess the effect of urban land-use change on the storage of SOC, we compared SOC stocks of turf grass and native cover types of two metropolitan areas (Baltimore, MD, and Denver...

Mechanisms underlying the control of responses to predator odours in aquatic prey.

PubMed

Mitchell, Matthew D; Bairos-Novak, Kevin R; Ferrari, Maud C O

2017-06-01

In aquatic systems, chemical cues are a major source of information through which animals are able to assess the current state of their environment to gain information about local predation risk. Prey use chemicals released by predators (including cues from a predator's diet) and other prey (such as alarm cues and disturbance cues) to mediate a range of behavioural, morphological and life-history antipredator defences. Despite the wealth of knowledge on the ecology of antipredator defences, we know surprisingly little about the physiological mechanisms that control the expression of these defensive traits. Here, we summarise the current literature on the mechanisms known to specifically mediate responses to predator odours, including dietary cues. Interestingly, these studies suggest that independent pathways may control predator-specific responses, highlighting the need for greater focus on predator-derived cues when looking at the mechanistic control of responses. Thus, we urge researchers to tease apart the effects of predator-specific cues (i.e. chemicals representing a predator's identity) from those of diet-mediated cues (i.e. chemicals released from a predator's diet), which are known to mediate different ecological endpoints. Finally, we suggest some key areas of research that would greatly benefit from a more mechanistic approach. © 2017. Published by The Company of Biologists Ltd.

Physical trade-offs shape the evolution of buoyancy control in sharks.

PubMed

Gleiss, Adrian C; Potvin, Jean; Goldbogen, Jeremy A

2017-11-15

Buoyancy control is a fundamental aspect of aquatic life that has major implications for locomotor performance and ecological niche. Unlike terrestrial animals, the densities of aquatic animals are similar to the supporting fluid, thus even small changes in body density may have profound effects on locomotion. Here, we analysed the body composition (lipid versus lean tissue) of 32 shark species to study the evolution of buoyancy. Our comparative phylogenetic analyses indicate that although lean tissue displays minor positive allometry, liver volume exhibits pronounced positive allometry, suggesting that larger sharks evolved bulkier body compositions by adding lipid tissue to lean tissue rather than substituting lean for lipid tissue, particularly in the liver. We revealed a continuum of buoyancy control strategies that ranged from more buoyant sharks with larger livers in deeper ecosystems to relatively denser sharks with small livers in epipelagic habitats. Across this eco-morphological spectrum, our hydrodynamic modelling suggests that neutral buoyancy yields lower drag and more efficient steady swimming, whereas negative buoyancy may be more efficient during accelerated movements. The evolution of buoyancy control in sharks suggests that ecological and physiological factors mediate the selective pressures acting on these traits along two major gradients, body size and habitat depth. © 2017 The Author(s).

Water Hyacinth in China: A Sustainability Science-Based Management Framework

NASA Astrophysics Data System (ADS)

Lu, Jianbo; Wu, Jianguo; Fu, Zhihui; Zhu, Lei

2007-12-01

The invasion of water hyacinth ( Eichhornia crassipes) has resulted in enormous ecological and economic consequences worldwide. Although the spread of this weed in Africa, Australia, and North America has been well documented, its invasion in China is yet to be fully documented. Here we report that since its introduction about seven decades ago, water hyacinth has infested many water bodies across almost half of China’s territory, causing a decline of native biodiversity, alteration of ecosystem services, deterioration of aquatic environments, and spread of diseases affecting human health. Water hyacinth infestations have also led to enormous economic losses in China by impeding water flows, paralyzing navigation, and damaging irrigation and hydroelectricity facilities. To effectively control the rampage of water hyacinth in China, we propose a sustainability science-based management framework that explicitly incorporates principles from landscape ecology and Integrated Pest Management. This framework emphasizes multiple-scale long-term monitoring and research, integration among different control techniques, combination of control with utilization, and landscape-level adaptive management. Sustainability science represents a new, transdisciplinary paradigm that integrates scientific research, technological innovation, and socioeconomic development of particular regions. Our proposed management framework is aimed to broaden the currently dominant biological control-centered view in China and to illustrate how sustainability science can be used to guide the research and management of water hyacinth.

Health is Power: an ecological, theory-based health intervention for women of color.

PubMed

Lee, Rebecca E; Medina, Ashley V; Mama, Scherezade K; Reese-Smith, Jacqueline Y; O'Connor, Daniel P; Brosnan, Marcella; Cubbin, Catherine; McMillan, Tracy; Estabrooks, Paul A

2011-11-01

Physical inactivity and poor dietary habits plague Americans as health challenges, with women of color most vulnerable to their detrimental effects. Individually focused interventions have not demonstrated lasting success, possibly due to the lack of focus on sustainable social and physical environment factors. This manuscript describes the rationale, design and methodology of Health Is Power (HIP), a transcultural, community based, randomized controlled trial that investigated the effectiveness of a group cohesion intervention to increase physical activity and improve dietary habits in African American and Hispanic or Latina women in Houston and Austin, Texas. The intervention development was guided by group dynamics principles anchored within an ecologic model. Women participated in three health assessments and a six month face to face intervention that included evidence-based behavioral methods - integrated into strategies to promote group cohesion - framed to account for environmental factors contributing to health disparities. Women participated in team building activities, environmental mapping exercises, and supervised walks or taste tests. Neighborhood contextual and environmental measures are described to test ecologic factors that may contribute to behavioral maintenance. Theoretically guided interventions that account for multiple levels of influence in behavior initiation and maintenance stand to improve health outcomes in vulnerable populations. Copyright © 2011 Elsevier Inc. All rights reserved.

Health Is Power: an Ecological Theory-based Health Intervention for Women of Color

PubMed Central

Lee, Rebecca E.; Medina, Ashley V.; Mama, Scherezade K.; Reese-Smith, Jacqueline Y.; O’Connor, Daniel P.; Brosnan, Marcella; Cubbin, Catherine; McMillan, Tracy; Estabrooks, Paul A.

2011-01-01

Objective Physical inactivity and poor dietary habits plague Americans as health challenges, with women of color most vulnerable to their detrimental effects. Individually focused interventions have not demonstrated lasting success, possibly due to the lack of focus on sustainable social and physical environment factors. This manuscript describes the rationale, design and methodology of Health Is Power (HIP), a transcultural, community based, randomized controlled trial that investigated the effectiveness of a group cohesion intervention to increase physical activity and improve dietary habits in African American and Hispanic or Latina women in Houston and Austin, Texas. Methods The intervention development was guided by group dynamics principles anchored within an ecologic model. Results Women participated in three health assessments and a six month face to face intervention that included evidence-based behavioral methods—integrated into strategies to promote group cohesion—framed to account for environmental factors contributing to health disparities. Women participated in team building activities, environmental mapping exercises, and supervised walks or taste tests. Conclusions Neighborhood contextual and environmental measures are described to test ecologic factors that may contribute to behavioral maintenance. Theoretically guided interventions that account for multiple levels of influence in behavior initiation and maintenance stand to improve health outcomes in vulnerable populations. PMID:21782975

[Landscape structure and ecological coupling analysis of ecotone on the west Sonnen Plain].

PubMed

Song, Changchun; Deng, Wei; Song, Xinshan

2003-09-01

Ecotone is a special zone in the landscape, which is very susceptive to the changes in environmental conditions, and hence, is prone to the disturbance by unfavorable conditions. Human activity has a series of positive and negative effects on it, and greatly changes the geo-chemical process in the ecosystem. In the ecosystem, especially in the ecotone, different systems and regimes are interconnected and inter-determined. For the sustainable development of ecosystem and the protection and rational utilization of resources, it is of great importance to study this internal relationship and to seek rational regulation and control measures. With the ecotone in the west Songnen Plain as an example, and based on the studies of the topography, physiognomy, soil, vegetation, and their geographic distribution in the ecotone., this paper explained the structure of the ecological landscape, and quantitatively analyzed the ecological geo-chemical processes under different landscape conditions. In addition, this paper also tried to make coupling analyses to the ecologic succession and the landscape geo-chemical environment. Under current conditions, the succession of plant communities and the shift of soil landscape geo-chemical conditions in the west Songnen Plain are almost co-instantaneous, and these two factors can inter-determined under certain conditions.

Changes of toxic metals during biological stabilization and their potential ecological risk assessment.

PubMed

Wang, Hou-cheng; Zeng, Zheng-zhong; Zhang, He-fei; Nan, Zhong-ren

2015-01-01

With various disadvantages of pollution control technologies for toxic metal-contaminated soil, we mixed contaminated soil with sludge for in situ composting to stabilize toxic metals, so plants are enriched to take up the toxic metals. When simulating the above, we added toxic metal solution into sewage sludge, and then composed it with steel slag to determine inhibition of the availability of toxic metals. When toxic metals were added into sludge, the potential ecological index and geoaccumulation index of Cd became high while Zn was low. Steel slag had an inhibited availability of Cd, and when the adjunction of steel slag was 7%, the availability of Cd was lowest. Steel slag promoted the availability of Zn, and when the adjunction of steel slag was 27%, the availability of Zn was highest. Results showed that during composting, with increasing steel slag, Cd stabilizing time was reached sooner but Zn stabilizing time was slower, and the availability of all metals became lower. In the end, composting inhibited the potential ecological index of Cd, but it promoted the potential ecological index of Zn. Steel slag promoted the stability of Cd and Zn as Fe/Mn oxide-bound and residual species. Therefore, composting sludge and steel slag could be used as an effective inhibitor of Zn and Cd pollution.

Governance matters: an ecological association between governance and child mortality

PubMed Central

Lin, Ro-Ting; Chien, Lung-Chang; Chen, Ya-Mei; Chan, Chang-Chuan

2014-01-01

Background Governance of a country may have widespread effects on the health of its population, yet little is known about the effect of governance on child mortality in a country that is undergoing urbanization, economic development, and disease control. Methods We obtained indicators of six dimensions of governance (perceptions of voice and accountability, political stability and absence of violence, government effectiveness, regulatory quality, rule of law, and control of corruption) and national under-5 mortality rates for 149 countries between 1996 and 2010. We applied a semi-parametric generalized additive mixed model to examine associations after controlling for the effects of development factors (urbanization level and economy), disease control factors (hygienic conditions and vaccination rates), health expenditures, air quality, and time. Results Governance, development, and disease control showed clear inverse relations with the under-5 mortality rate (p<0.001). Per unit increases in governance, development, and disease control factors, the child mortality rate had a 0.901-, 0.823-, and 0.922-fold decrease, respectively, at fixed levels of the other two factors. Conclusions In the effort to reduce the global under-5 mortality rate, addressing a country's need for better governance is as important as improvements in development and disease control. PMID:24711600

Optimal control of malaria: combining vector interventions and drug therapies.

PubMed

Khamis, Doran; El Mouden, Claire; Kura, Klodeta; Bonsall, Michael B

2018-04-24

The sterile insect technique and transgenic equivalents are considered promising tools for controlling vector-borne disease in an age of increasing insecticide and drug-resistance. Combining vector interventions with artemisinin-based therapies may achieve the twin goals of suppressing malaria endemicity while managing artemisinin resistance. While the cost-effectiveness of these controls has been investigated independently, their combined usage has not been dynamically optimized in response to ecological and epidemiological processes. An optimal control framework based on coupled models of mosquito population dynamics and malaria epidemiology is used to investigate the cost-effectiveness of combining vector control with drug therapies in homogeneous environments with and without vector migration. The costs of endemic malaria are weighed against the costs of administering artemisinin therapies and releasing modified mosquitoes using various cost structures. Larval density dependence is shown to reduce the cost-effectiveness of conventional sterile insect releases compared with transgenic mosquitoes with a late-acting lethal gene. Using drug treatments can reduce the critical vector control release ratio necessary to cause disease fadeout. Combining vector control and drug therapies is the most effective and efficient use of resources, and using optimized implementation strategies can substantially reduce costs.

'I'm Black and I'm Proud': A Majority Ecological Context Protects Affective Aspects of Black Identity Under Stereotype Threat.

PubMed

Oliver, Andre'; Andemeskel, Ghilamichael; King, Carlise R; Wallace, Lyndsey; McDougal, Serie; Monteiro, Kenneth P; Ben-Zeev, Avi

2017-12-01

We provide evidence that stereotype threat, a phenomenon that causes stigmatized individuals to experience group-based evaluative concerns (Steele in Am Psychol 52:613-629, 1997; Whistling Vivaldi and other clues to how stereotypes affect us, W.W. Norton, New York, 2010), impacts affective aspects of Black identity as a function of majority versus minority ecological contexts. Black/African-American students, enrolled in either Africana Studies (Black ecological majority) or Psychology (Black ecological minority), completed private and public regard subscales from the Multidimensional Inventory of Black Identity (Sellers et al. in Pers Soc Psychol Rev 2:18-39, 1998) at baseline (Time 1) and after being randomly assigned to a stereotype threat or no-threat/control condition (Time 2). In threat, participants were introduced to a 'puzzle' task as diagnostic of intellectual abilities, whereas in no-threat the same task was introduced as culture fair, such that people from different racial/ethnic groups had performed similarly on this task in the past. In Psychology, students under threat exhibited a simultaneous decrease and increase in private and public regard, respectively, a pattern shown in the literature to be associated with discrimination-based distress and lesser well-being in Black ecological minority environments. In contrast, Africana Studies students' racial identity under threat remained intact. We discuss the protective effects of Africana Studies on racial identity and implications for educational reform.

‘I’m Black and I’m Proud’: A Majority Ecological Context Protects Affective Aspects of Black Identity Under Stereotype Threat

PubMed Central

Oliver, Andre’; Andemeskel, Ghilamichael; King, Carlise R.; Wallace, Lyndsey; McDougal, Serie; Monteiro, Kenneth P.

2018-01-01

We provide evidence that stereotype threat, a phenomenon that causes stigmatized individuals to experience group-based evaluative concerns (Steele in Am Psychol 52:613–629, 1997; Whistling Vivaldi and other clues to how stereotypes affect us, W.W. Norton, New York, 2010), impacts affective aspects of Black identity as a function of majority versus minority ecological contexts. Black/African-American students, enrolled in either Africana Studies (Black ecological majority) or Psychology (Black ecological minority), completed private and public regard subscales from the Multidimensional Inventory of Black Identity (Sellers et al. in Pers Soc Psychol Rev 2:18–39, 1998) at baseline (Time 1) and after being randomly assigned to a stereotype threat or no-threat/control condition (Time 2). In threat, participants were introduced to a ‘puzzle’ task as diagnostic of intellectual abilities, whereas in no-threat the same task was introduced as culture fair, such that people from different racial/ethnic groups had performed similarly on this task in the past. In Psychology, students under threat exhibited a simultaneous decrease and increase in private and public regard, respectively, a pattern shown in the literature to be associated with discrimination-based distress and lesser well-being in Black ecological minority environments. In contrast, Africana Studies students’ racial identity under threat remained intact. We discuss the protective effects of Africana Studies on racial identity and implications for educational reform. PMID:29657583

REINFORCEMENT OF STICKLEBACK MATE PREFERENCES: SYMPATRY BREEDS CONTEMPT.

PubMed

Rundle, Howard D; Schluter, Dolph

1998-02-01

Detailed studies of reproductive isolation and how it varies among populations can provide valuable insight into the mechanisms of speciation. Here we investigate how the strength of premating isolation varies between sympatric and allopatric populations of threespine sticklebacks to test a prediction of the hypothesis of reinforcement: that interspecific mate discrimination should be stronger in sympatry than in allopatry. In conducting such tests, it is important to control for ecological character displacement between sympatric species because ecological character divergence may strengthen prezygotic isolation as a by-product. We control for ecological character displacement by comparing mate preferences of females from a sympatric population (benthics) with mate preferences of females from two allopatric populations that most closely resemble the sympatric benthic females in ecology and morphology. No-choice mating trials indicate that sympatric benthic females mate less readily with heterospecific (limnetic) than conspecific (benthic) males, whereas two different populations of allopatric females resembling benthics show no such discrimination. These differences demonstrate reproductive character displacement of benthic female mate choice. Previous studies have established that hybridization between sympatric species occurred in the past in the wild and that hybrid offspring have lower fitness than either parental species, thus providing conditions under which natural selection would favor individuals that do not hybridize. Results are therefore consistent with the hypothesis that female mate preferences have evolved as a response to reduced hybrid fitness (reinforcement), although direct effects of sympatry or a biased extinction process could also produce the pattern. Males of the other sympatric species (limnetics) showed a preference for smaller females, in contrast to the inferred ancestral preference for larger females, suggesting reproductive character displacement of limnetic male mate preferences as well. © 1998 The Society for the Study of Evolution.

Restoration of the fire-grazing interaction in Artemisia filifolia shrubland

USGS Publications Warehouse

Winter, S.L.; Fuhlendorf, S.D.; Goad, C.L.; Davis, C.A.; Hickman, K.R.; Leslie, David M.

2012-01-01

Patterns of landscape heterogeneity are crucial to the maintenance of biodiversity in shrublands and grasslands, yet management practices in these ecosystems typically seek to homogenize landscapes. Furthermore, there is limited understanding of how the interaction of ecological processes, such as fire and grazing, affects patterns of heterogeneity at different spatial scales. We conducted research in Artemisia filifolia (Asteraceae) shrublands located in the southern Great Plains of North America to determine the effect of restoring the fire-grazing interaction on vegetation structure. Data were collected for 3years in replicated pastures grazed by cattle Bos taurus where the fire-grazing interaction had been restored (fire and grazing=treatment pastures) and in pastures that were grazed but remained unburned (grazing only, no fire=control pastures). The effect of the fire-grazing interaction on heterogeneity (variance) of vegetation structure was assessed at scales from 12??5m 2 to 609ha. Most measurements of vegetation structure within treatment pastures differed from control pastures for 1-3years after being burned but were thereafter similar to the values found in unburned control pastures. Treatment pastures were characterized by a lower amount of total heterogeneity and a lower amount of heterogeneity through time. Heterogeneity of vegetation structure tended to decrease as the scale of measurement increased in both treatment and control pastures. There was deviation from this trend, however, in the treatment pastures that exhibited much higher heterogeneity at the patch scale (mean patch size=202ha) of measurement, the scale at which patch fires were conducted. Synthesis and applications.Vegetation structure in A. filifolia shrublands of our study was readily altered by the fire-grazing interaction but also demonstrated substantial resilience to these effects. The fire-grazing interaction also changed the total amount of heterogeneity characterizing this system, the scale at which heterogeneity in this system was expressed and the amount of heterogeneity expressed through time. Land managers seeking to impose a shifting mosaic of heterogeneity on this vegetation type can do so by restoring the fire-grazing interaction with potential conservation benefits similar to what has been achieved in other ecosystems where historic cycles of disturbance and rest have been restored. ?? 2011 The Authors. Journal of Applied Ecology ?? 2011 British Ecological Society.

Promoting biodiversity values of small forest patches in agricultural landscapes: Ecological drivers and social demand.

PubMed

Varela, Elsa; Verheyen, Kris; Valdés, Alicia; Soliño, Mario; Jacobsen, Jette B; De Smedt, Pallieter; Ehrmann, Steffen; Gärtner, Stefanie; Górriz, Elena; Decocq, Guillaume

2018-04-01

Small forest patches embedded in agricultural (and peri-urban) landscapes in Western Europe play a key role for biodiversity conservation with a recognized capacity of delivering a wide suite of ecosystem services. Measures aimed to preserve these patches should be both socially desirable and ecologically effective. This study presents a joint ecologic and economic assessment conducted on small forest patches in Flanders (Belgium) and Picardie (N France). In each study region, two contrasted types of agricultural landscapes were selected. Open field (OF) and Bocage (B) landscapes are distinguished by the intensity of their usage and higher connectivity in the B landscapes. The social demand for enhancing biodiversity and forest structure diversity as well as for increasing the forest area at the expenses of agricultural land is estimated through an economic valuation survey. These results are compared with the outcomes of an ecological survey where the influence of structural features of the forest patches on the associated herbaceous diversity is assessed. The ecological and economic surveys show contrasting results; increasing tree species richness is ecologically more important for herbaceous diversity in the patch, but both tree species richness and herbaceous diversity obtain insignificant willingness to pay estimates. Furthermore, although respondents prefer the proposed changes to take place in the region where they live, we find out that social preferences and ecological effectiveness do differ between landscapes that represent different intensities of land use. Dwellers where the landscape is perceived as more "degraded" attach more value to diversity enhancement, suggesting a prioritization of initiatives in these area. In contrast, the ecological analyses show that prioritizing the protection and enhancement of the relatively better-off areas is more ecologically effective. Our study calls for a balance between ecological effectiveness and welfare benefits, suggesting that cost effectiveness studies should consider these approaches jointly. Copyright © 2017 Elsevier B.V. All rights reserved.

Toward refined environmental scenarios for ecological risk assessment of down-the-drain chemicals in freshwater environments.

PubMed

Franco, Antonio; Price, Oliver R; Marshall, Stuart; Jolliet, Olivier; Van den Brink, Paul J; Rico, Andreu; Focks, Andreas; De Laender, Frederik; Ashauer, Roman

2017-03-01

Current regulatory practice for chemical risk assessment suffers from the lack of realism in conventional frameworks. Despite significant advances in exposure and ecological effect modeling, the implementation of novel approaches as high-tier options for prospective regulatory risk assessment remains limited, particularly among general chemicals such as down-the-drain ingredients. While reviewing the current state of the art in environmental exposure and ecological effect modeling, we propose a scenario-based framework that enables a better integration of exposure and effect assessments in a tiered approach. Global- to catchment-scale spatially explicit exposure models can be used to identify areas of higher exposure and to generate ecologically relevant exposure information for input into effect models. Numerous examples of mechanistic ecological effect models demonstrate that it is technically feasible to extrapolate from individual-level effects to effects at higher levels of biological organization and from laboratory to environmental conditions. However, the data required to parameterize effect models that can embrace the complexity of ecosystems are large and require a targeted approach. Experimental efforts should, therefore, focus on vulnerable species and/or traits and ecological conditions of relevance. We outline key research needs to address the challenges that currently hinder the practical application of advanced model-based approaches to risk assessment of down-the-drain chemicals. Integr Environ Assess Manag 2017;13:233-248. © 2016 SETAC. © 2016 SETAC.

The relative importance of rapid evolution for plant-microbe interactions depends on ecological context.

PubMed

Terhorst, Casey P; Lennon, Jay T; Lau, Jennifer A

2014-06-22

Evolution can occur on ecological time-scales, affecting community and ecosystem processes. However, the importance of evolutionary change relative to ecological processes remains largely unknown. Here, we analyse data from a long-term experiment in which we allowed plant populations to evolve for three generations in dry or wet soils and used a reciprocal transplant to compare the ecological effect of drought and the effect of plant evolutionary responses to drought on soil microbial communities and nutrient availability. Plants that evolved under drought tended to support higher bacterial and fungal richness, and increased fungal : bacterial ratios in the soil. Overall, the magnitudes of ecological and evolutionary effects on microbial communities were similar; however, the strength and direction of these effects depended on the context in which they were measured. For example, plants that evolved in dry environments increased bacterial abundance in dry contemporary environments, but decreased bacterial abundance in wet contemporary environments. Our results suggest that interactions between recent evolutionary history and ecological context affect both the direction and magnitude of plant effects on soil microbes. Consequently, an eco-evolutionary perspective is required to fully understand plant-microbe interactions.

[Comprehensive evaluation and selection of urban eco-engineering virescent trees in Shenyang City].

PubMed

Lu, Min; Jiang, Fengqi; Li, Yingjie

2004-07-01

Urban virescence eco-engineering is the core of urban eco-environmental construction, which can promote urban sustainable development. In urban virescence eco-engineering, the comprehensive evaluation of ecological adapt-ability and ecological effect of urban plants is the scientific basis of rational application and selection of urban garden plants. The ecological effect and integrative functions of urban virescence eco-engineering depend upon the selection and layout of garden plants. Using the methods of garden expert consultation and evaluation, this paper established systematically integrative evaluation and application indices of virescence plants in Shenyang City, from the aspects of ecological adaptability, ecological effect, beautification effect, resistance to plant diseases and insect pests, anti-pollution and economic results. According to garden experts evaluation and location of Shenyang, 200 sorts of virescence trees were evaluated and classified on the basis of the comprehensive evaluation system of virescence trees, and using cold resistance, drought resistance, barren resistance, plant diseases and insect pests resistance, anti-pollution, ornamental quality and ecological effects as the indexes. The results showed that the number of first rank trees was 58, the second was 93, methods of third was 38, and the fourth was 11, ranked by integrative performance.

CELSS science needs

NASA Technical Reports Server (NTRS)

Rummel, J. D.

1986-01-01

Questions and areas of study that need to be persued in order to develope a Controlled Ecological Life Support System are posed. Research topics needing attention are grouped under various leadings: ecology, genetics, plant pathology, cybernetics, chemistry, computer science, fluid dynamics, optics, and solid-state physics.

The raison d'être of chemical ecology.

PubMed

Raguso, Robert A; Agrawal, Anurag A; Douglas, Angela E; Jander, Georg; Kessler, André; Poveda, Katja; Thaler, Jennifer S

2015-03-01

Chemical ecology is a mechanistic approach to understanding the causes and consequences of species interactions, distribution, abundance, and diversity. The promise of chemical ecology stems from its potential to provide causal mechanisms that further our understanding of ecological interactions and allow us to more effectively manipulate managed systems. Founded on the notion that all organisms use endogenous hormones and chemical compounds that mediate interactions, chemical ecology has flourished over the past 50 years since its origin. In this essay we highlight the breadth of chemical ecology, from its historical focus on pheromonal communication, plant-insect interactions, and coevolution to frontier themes including community and ecosystem effects of chemically mediated species interactions. Emerging approaches including the -omics, phylogenetic ecology, the form and function of microbiomes, and network analysis, as well as emerging challenges (e.g., sustainable agriculture and public health) are guiding current growth of this field. Nonetheless, the directions and approaches we advocate for the future are grounded in classic ecological theories and hypotheses that continue to motivate our broader discipline.

Controlling Culex pipiens: antagonists are more efficient than a neonicotinoid insecticide.

PubMed

Meyabeme Elono, Alvine Larissa; Foit, Kaarina; Duquesne, Sabine; Liess, Matthias

2018-06-01

Species vulnerability to pesticides depends on physiological sensitivity, the potential to recover, and the ecological context. We assessed the vulnerability of the mosquito Culex pipiens to a repeated treatment with thiacloprid in outdoor microcosms with and without antagonists (competitive and predatory invertebrates). Microcosms were treated repeatedly (three times) with thiacloprid at a concentration of 0.1, 1, or 10 µg/liter. In microcosms without antagonists, the abundance of Cx. pipiens larvae decreased moderately after the second and the third exposures to 10 µg/liter thiacloprid. In microcosms with antagonists, the abundance of Cx. pipiens larvae declined to approximately zero in the control group and the low concentration treatments during the five weeks of observation. By contrast, the abundance of Cx. pipiens larvae temporarily increased at 10 µg/liter thiacloprid after the second and third contamination. We explained this positive effect on the development of Cx. pipiens because of the decrease in competition due to the elimination of sensitive antagonists combined with the high recovery potential of Cx. pipiens. Based on these results, natural antagonists must be supported for the sustainable control of mosquitoes. © 2018 The Society for Vector Ecology.

A comparative study of integrated pest management strategies based on impulsive control.

PubMed

Páez Chávez, Joseph; Jungmann, Dirk; Siegmund, Stefan

2018-12-01

The paper presents a comprehensive numerical study of mathematical models used to describe complex biological systems in the framework of integrated pest management. Our study considers two specific ecosystems that describe the application of control mechanisms based on pesticides and natural enemies, implemented in an impulsive and periodic manner, due to which the considered models belong to the class of impulsive differential equations. The present work proposes a numerical approach to study such type of models in detail, via the application of path-following (continuation) techniques for nonsmooth dynamical systems, via the novel continuation platform COCO (Dankowicz and Schilder). In this way, a detailed study focusing on the influence of selected system parameters on the effectiveness of the pest control scheme is carried out for both ecological scenarios. Furthermore, a comparative study is presented, with special emphasis on the mechanisms upon which a pest outbreak can occur in the considered ecosystems. Our study reveals that such outbreaks are determined by the presence of a branching point found during the continuation analysis. The numerical investigation concludes with an in-depth study of the state-dependent pesticide mortality considered in one of the ecological scenarios.

ELF communications system ecological monitoring program: Pollinating insect studies

NASA Astrophysics Data System (ADS)

Strickler, Karen; Schriber, J. Mark

1994-11-01

High voltage transmission lines and the earth's and other magnetic fields have been shown to affect honeybee reproduction, survival, orientation, and nest structure. ELY EM fields could have similar effects on native megachilid bees. Two species in the genus Megachile were abundant in artificial nests at experimental and control areas in Dickinson and Iron Counties in Michigan. Data on their nest architecture, nest activity, and emergence/mortality were collected between 1983 and 1993. Eight hypotheses concerning the possible effects of ELY EM fields were considered using these data. The ELY antenna has been fully operational since the summer of 1989. Tests of the hypotheses compare control vs. experimental areas before and after the ELY antenna became fully operational.

Insularity and the determinants of lizard population density.

PubMed

Buckley, Lauren B; Jetz, Walter

2007-06-01

The relative effects of resource availability and partitioning on animal population density are unresolved yet central to ecology and conservation. Species-depauperate islands offer an intriguing test case. Across 643 lizard populations from around the world, local abundances are one order of magnitude higher on islands than on mainlands, even when controlled for resource availability. On mainlands, predator and competitor richness only weakly correlate with lizard densities. On islands, sharp reductions in predator and competitor richness are the dominant drivers of lizard abundance. Our results demonstrate the dramatic effect insularity has on the interplay between biotic and abiotic control of animal abundances and the heightened sensitivity of island communities to species' losses and gains.

Pathogen survival trajectories: an eco-environmental approach to the modeling of human campylobacteriosis ecology.

PubMed Central

Skelly, Chris; Weinstein, Phil

2003-01-01

Campylobacteriosis, like many human diseases, has its own ecology in which the propagation of human infection and disease depends on pathogen survival and finding new hosts in order to replicate and sustain the pathogen population. The complexity of this process, a process common to other enteric pathogens, has hampered control efforts. Many unknowns remain, resulting in a poorly understood disease ecology. To provide structure to these unknowns and help direct further research and intervention, we propose an eco-environmental modeling approach for campylobacteriosis. This modeling approach follows the pathogen population as it moves through the environments that define the physical structure of its ecology. In this paper, we term the ecologic processes and environments through which these populations move "pathogen survival trajectories." Although such a modeling approach could have veterinary applications, our emphasis is on human campylobacteriosis and focuses on human exposures to Campylobacter through feces, food, and aquatic environments. The pathogen survival trajectories that lead to human exposure include ecologic filters that limit population size, e.g., cooking food to kill Campylobacter. Environmental factors that influence the size of the pathogen reservoirs include temperature, nutrient availability, and moisture availability during the period of time the pathogen population is moving through the environment between infected and susceptible hosts. We anticipate that the modeling approach proposed here will work symbiotically with traditional epidemiologic and microbiologic research to help guide and evaluate the acquisition of new knowledge about the ecology, eventual intervention, and control of campylobacteriosis. PMID:12515674

Nutritional and cultural aspects of plant species selection for a controlled ecological life support system

NASA Technical Reports Server (NTRS)

Hoff, J. E.; Howe, J. M.; Mitchell, C. A.

1982-01-01

The feasibility of using higher plants in a controlled ecological life support system is discussed. Aspects of this system considered important in the use of higher plants include: limited energy, space, and mass, and problems relating to cultivation and management of plants, food processing, the psychological impact of vegetarian diets, and plant propagation. A total of 115 higher plant species are compared based on 21 selection criteria.

Controlled Ecological Life Support System: Use of Higher Plants

NASA Technical Reports Server (NTRS)

Tibbits, T. W.; Alford, D. K.

1982-01-01

Results of two workshops concerning the use of higher plants in Controlled Ecological Life Support Systems (CELSS) are summarized. Criteria for plant selection were identified from these categories: food production, nutrition, oxygen production and carbon dioxide utilization, water recycling, waste recycling, and other morphological and physiological considerations. Types of plant species suitable for use in CELSS, growing procedures, and research priorities were recommended. Also included are productivity values for selected plant species.

Evaluation on island ecological vulnerability and its spatial heterogeneity.

PubMed

Chi, Yuan; Shi, Honghua; Wang, Yuanyuan; Guo, Zhen; Wang, Enkang

2017-12-15

The evaluation on island ecological vulnerability (IEV) can help reveal the comprehensive characteristics of the island ecosystem and provide reference for controlling human activities on islands. An IEV evaluation model which reflects the land-sea dual features, natural and anthropogenic attributes, and spatial heterogeneity of the island ecosystem was established, and the southern islands of Miaodao Archipelago in North China were taken as the study area. The IEV, its spatial heterogeneity, and its sensitivities to the evaluation elements were analyzed. Results indicated that the IEV was in status of mild vulnerability in the archipelago scale, and population pressure, ecosystem productivity, environmental quality, landscape pattern, and economic development were the sensitive elements. The IEV showed significant spatial heterogeneities both in land and surrounding waters sub-ecosystems. Construction scale control, optimization of development allocation, improvement of exploitation methods, and reasonable ecological construction are important measures to control the IEV. Copyright © 2017 Elsevier Ltd. All rights reserved.

Evaluate and characterize mechanisms controlling transport, fate, and effects of army smokes in the aerosol wind tunnel: Transport, transformations, fate, and terrestrial ecological effects of hexachloroethane obscurant smokes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cataldo, D.A.; Ligotke, M.W.; Bolton, H. Jr.

1989-09-01

The terrestrial transport, chemical fate, and ecological effects of hexachloroethane (HC) smoke were evaluated under controlled wind tunnel conditions. The primary objectives of this research program are to characterize and assess the impacts of smoke and obscurants on: (1) natural vegetation characteristic of US Army training sites in the United States; (2) physical and chemical properties of soils representative of these training sites; and (3) soil microbiological and invertebrate communities. Impacts and dose/responses were evaluated based on exposure scenarios, including exposure duration, exposure rate, and sequential cumulative dosing. Key to understanding the environmental impacts of HC smoke/obscurants is establishing themore » importance of environmental parameters such as relative humidity and wind speed on airborne aerosol characteristics and deposition to receptor surfaces. Direct and indirect biotic effects were evaluated using five plant species and two soil types. HC aerosols were generated in a controlled atmosphere wind tunnel by combustion of hexachloroethane mixtures prepared to simulate normal pot burn rates and conditions. The aerosol was characterized and used to expose plant, soil, and other test systems. Particle sizes of airborne HC ranged from 1.3 to 2.1 {mu}m mass median aerodynamic diameter (MMAD), and particle size was affected by relative humidity over a range of 20% to 85%. Air concentrations employed ranged from 130 to 680 mg/m{sup 3}, depending on exposure scenario. Chlorocarbon concentrations within smokes, deposition rates for plant and soil surfaces, and persistence were determined. The fate of principal inorganic species (Zn, Al, and Cl) in a range of soils was assessed.« less

Ecology and pathogenicity of gastrointestinal Streptococcus bovis.

PubMed

Herrera, Paul; Kwon, Young Min; Ricke, Steven C

2009-01-01

Streptococcus bovis is an indigenous resident in the gastrointestinal tracts of both humans and animals. S. bovis is one of the major causes of bacterial endocarditis and has been implicated in the incidence of human colon cancer, possibly due to chronic inflammatory response at the site of intestinal colonization. Certain feeding regimens in ruminants can lead to overgrowth of S. bovis in the rumen, resulting in the over-production of lactate and capsular polysaccharide causing acute ruminal acidosis and bloat, respectively. There are multiple strategies in controlling acute lactic acidosis and bloat. The incidence of the two diseases may be controlled by strict dietary management. Gradual introduction of grain-based diets and the feeding of coarsely chopped roughage decrease the incidence of the two disease entities. Ionophores, which have been used to enhance feed conversion and growth rate in cattle, have been shown to inhibit the growth of lactic acid bacteria in the rumen. Other methods of controlling lactic acid bacteria in the ruminal environment (dietary supplementation of long-chain fatty acids, induction of passive and active immune responses to the bacteria, and the use of lytic bacteriophages) have also been investigated. It is anticipated that through continued in-depth ecological analysis of S. bovis the characteristics responsible for human and animal pathogenesis would be sufficiently identified to a point where more effective control strategies for the control of this bacteria can be developed.

Environmental (Saprozoic) Pathogens of Engineered Water Systems: Understanding Their Ecology for Risk Assessment and Management

PubMed Central

Ashbolt, Nicholas J.

2015-01-01

Major waterborne (enteric) pathogens are relatively well understood and treatment controls are effective when well managed. However, water-based, saprozoic pathogens that grow within engineered water systems (primarily within biofilms/sediments) cannot be controlled by water treatment alone prior to entry into water distribution and other engineered water systems. Growth within biofilms or as in the case of Legionella pneumophila, primarily within free-living protozoa feeding on biofilms, results from competitive advantage. Meaning, to understand how to manage water-based pathogen diseases (a sub-set of saprozoses) we need to understand the microbial ecology of biofilms; with key factors including biofilm bacterial diversity that influence amoebae hosts and members antagonistic to water-based pathogens, along with impacts from biofilm substratum, water temperature, flow conditions and disinfectant residual—all control variables. Major saprozoic pathogens covering viruses, bacteria, fungi and free-living protozoa are listed, yet today most of the recognized health burden from drinking waters is driven by legionellae, non-tuberculous mycobacteria (NTM) and, to a lesser extent, Pseudomonas aeruginosa. In developing best management practices for engineered water systems based on hazard analysis critical control point (HACCP) or water safety plan (WSP) approaches, multi-factor control strategies, based on quantitative microbial risk assessments need to be developed, to reduce disease from largely opportunistic, water-based pathogens. PMID:26102291

Relationships fade with time: a meta-analysis of temporal trends in publication in ecology and evolution.

PubMed Central

Jennions, Michael D; Møller, Anders P

2002-01-01

Both significant positive and negative relationships between the magnitude of research findings (their 'effect size') and their year of publication have been reported in a few areas of biology. These trends have been attributed to Kuhnian paradigm shifts, scientific fads and bias in the choice of study systems. Here we test whether or not these isolated cases reflect a more general trend. We examined the relationship using effect sizes extracted from 44 peer-reviewed meta-analyses covering a wide range of topics in ecological and evolutionary biology. On average, there was a small but significant decline in effect size with year of publication. For the original empirical studies there was also a significant decrease in effect size as sample size increased. However, the effect of year of publication remained even after we controlled for sampling effort. Although these results have several possible explanations, it is suggested that a publication bias against non-significant or weaker findings offers the most parsimonious explanation. As in the medical sciences, non-significant results may take longer to publish and studies with both small sample sizes and non-significant results may be less likely to be published. PMID:11788035

Subjective well-being in times of social change: congruence of control strategies and perceived control.

PubMed

Grümer, Sebastian; Silbereisen, Rainer K; Heckhausen, Jutta

2013-01-01

This paper investigates the association between perceptions of broader changes in the social-ecological context and individuals' subjective well-being (SWB). Macro-level societal changes such as globalization or demographic change give rise to new demands for individual functioning at work and/or in the family. Such new demands associated with social change are stressful and likely to be related to lower levels of SWB. Being active agents, individuals attempt to deal with social change and its increasing demands to protect their SWB. The present study investigates which kinds of control strategies are most effective in protecting one's SWB. Specifically, we predicted that control strategies of goal engagement will be most effective under conditions of perceived high control, and control strategies of goal disengagement will be most effective under conditions of perceived low control. In a large sample of 2537 German adults, work- and family-related demands associated with social change were found to be negatively linked to SWB. Moreover and in line with the motivational theory of lifespan development, control strategies of goal engagement and disengagement were beneficial for SWB to the extent that they matched the perceived control of the demands associated with social change.

[Scale effect of Li-Xiang Railway construction impact on landscape pattern and its ecological risk].

PubMed

Wang, De-zhi; Qiu, Peng-hua; Fang, Yuan-min

2015-08-01

As a large corridor project, plateau railway has multiple points and passes various sensitive environments along the railway. The determination of the scope of impact on ecological environment from railway construction is often controversial in ecological impact assessment work. Taking the Tangbu-Jiantang section of Li-Xiang Railway as study object, and using present land use map (1:10000) in 2012 and DEM as data sources, corridor cutting degree index ( CCI) and cumulative effect index of corridor (CCEI) were established by topology, buffer zone and landscape metrics methods. Besides, the ecological risk index used for railway construction was improved. By quantitative analysis of characteristics of the spatio-temporal change of landscape pattern and its evolution style at different spatial scales before and after railway construction, the most appropriate evaluation scale of the railway was obtained. Then the characteristics of the spatio-temporal variation of ecological risk within this scale before and after railway construction were analyzed. The results indicated that the cutting model and degree of railway corridor to various landscape types could be effectively reflected by CCI, and the exposure and harm relations between risk sources and risk receptors of railway can be measured by CCEI. After the railway construction, the railway corridor would cause a great deal of middle cutting effect on the landscape along the railroad, which would influence wood land and grassland landscape most greatly, while would cause less effect of edge cutting and internal cutting. Landscape indices within the 600 m buffer zone demonstrated the most obvious scale effect, therefore, the 600 m zone of the railway was set as the most suitable range of ecological impact assessment. Before railway construction, the low ecological risk level covered the biggest part of the 600 m assessment zone. However, after the railway construction, the ecological risk increased significantly, and the most part of the study area was at the moderate ecological risk level. The ecological risk presented ring-shaped and multi-kernel patterns, and was lower in the southern part than in the northern part of the study area.

Effect-Based Tools for Monitoring and Predicting the Ecotoxicological Effects of Chemicals in the Aquatic Environment

PubMed Central

Connon, Richard E.; Geist, Juergen; Werner, Inge

2012-01-01

Ecotoxicology faces the challenge of assessing and predicting the effects of an increasing number of chemical stressors on aquatic species and ecosystems. Herein we review currently applied tools in ecological risk assessment, combining information on exposure with expected biological effects or environmental water quality standards; currently applied effect-based tools are presented based on whether exposure occurs in a controlled laboratory environment or in the field. With increasing ecological relevance the reproducibility, specificity and thus suitability for standardisation of methods tends to diminish. We discuss the use of biomarkers in ecotoxicology including ecotoxicogenomics-based endpoints, which are becoming increasingly important for the detection of sublethal effects. Carefully selected sets of biomarkers allow an assessment of exposure to and effects of toxic chemicals, as well as the health status of organisms and, when combined with chemical analysis, identification of toxicant(s). The promising concept of “adverse outcome pathways (AOP)” links mechanistic responses on the cellular level with whole organism, population, community and potentially ecosystem effects and services. For most toxic mechanisms, however, practical application of AOPs will require more information and the identification of key links between responses, as well as key indicators, at different levels of biological organization, ecosystem functioning and ecosystem services. PMID:23112741

Index to Ecology (Multimedia). Second Edition.

ERIC Educational Resources Information Center

University of Southern California, Los Angeles. National Information Center for Educational Media.

This expanded catalog lists over 8,000 films, filmstrips, videotapes, transparencies, audiotapes, and records dealing with environmental and ecological topics. Subjects include: amphibians, botany, birth control, city planning, evolution, food chains, farming, oceanography, and sea life. Titles are listed alphabetically. Though entries are not…

[Engineering issues of microbial ecology in space agriculture].

PubMed

Yamashita, Masamichi; Ishikawa, Yoji; Oshima, Tairo

2005-03-01

Closure of the materials recycle loop for water-foods-oxygen is the primary purpose of space agriculture on Mars and Moon. A microbial ecological system takes a part of agriculture to process our metabolic excreta and inedible biomass and convert them to nutrients and soil substrate for cultivating plants. If we extend the purpose of space agriculture to the creation and control of a healthy and pleasant living environment, we should realize that our human body should not be sterilized but exposed to the appropriate microbial environment. We are proposing a use of hyper-thermophilic aerobic composting microbial ecology in space agriculture. Japan has a broad historical and cultural background on this subject. There had been agriculture that drove a closed loop of materials between consuming cities and farming villages in vicinity. Recent environmental problems regarding garbage collection and processing in towns have motivated home electronics companies to innovate "garbage composting" machines with bacterial technology. Based on those matured technology, together with new insights on microbiology and microbial ecology, we have been developing a conceptual design of space agriculture on Moon and Mars. There are several issues to be answered in order to prove effectiveness of the use of microbial systems in space. 1) Can the recycled nutrients, processed by the hyper-thermal aerobic composting microbial ecology, be formed in the physical and chemical state or configuration, with which plants can uptake those nutrients? A possibility of removing any major components of fertilizer from its recycle loop is another item to be evaluated. 2) What are the merits of forming soil microbial ecology around the root system of plants? This might be the most crucial question. Recent researches exhibit various mutually beneficial relationships among soil microbiota and plants, and symbiotic ecology in composting bacteria. It is essential to understand those features, and define how to conduct preventive maintenance for keeping cultivating soil healthy and productive. 3) Does microbial ecology contribute to building sustainable and expandable human habitation by utilizing the on site extraterrestrial resources? We are assessing technical feasibility of converting regolith to farming soil and structural materials for space agriculture. In the case of Mars habitation, carbon dioxide and a trace amount of nitrogen in atmosphere, and potassium and phosphor in minerals are the sources we consider. Excess oxygen can be accumulated by woods cultivation and their use for lumber. 4) Is the operation of space agriculture robust and safe, if it adopts hyper-thermophilic aerobic microbial ecology? Any ecological system is complex and non-linear, and shows latency and memory effects in its response. It is highly important to understand those features to design and operate space agriculture without falling into the fatal failure. Assessment should be made on the microbial safety and preparation of the preventive measures to eliminate negative elements that would either retard agricultural production or harm the healthy environment. It is worth to mention that such space agriculture would be an effective engineering testbed to solve the global problem on energy and environment. Mars and Moon exploration itself is a good advocate of healthy curiosity expressed by the sustainable civilization of our humankind. We propose to work together towards Mars and Moon with microbial ecology to assure pleasant habitation there.

Tamarix as habitat for birds: Implications for riparian restoration in the Southwestern United States

USGS Publications Warehouse

Sogge, M.K.; Sferra, S.J.; Paxton, E.H.

2008-01-01

Exotic vegetation has become a major habitat component in many ecosystems around the world, sometimes dramatically changing the vegetation community structure and composition. In the southwestern United States, riparian ecosystems are undergoing major changes in part due to the establishment and spread of the exotic Tamarix (saltcedar, tamarisk). There are concerns about the suitability of Tamarix as habitat for birds. Although Tamarix habitats tend to support fewer species and individuals than native habitats, Arizona Breeding Bird Atlas data and Birds of North America accounts show that 49 species use Tamarix as breeding habitat. Importantly, the relative use of Tamarix and its quality as habitat vary substantially by geographic location and bird species. Few studies have examined how breeding in Tamarix actually affects bird survivorship and productivity; recent research on Southwestern Willow Flycatchers has found no negative effects from breeding in Tamarix habitats. Therefore, the ecological benefits and costs of Tamarix control are difficult to predict and are likely to be species specific and site specific. Given the likelihood that high-quality native riparian vegetation will not develop at all Tamarix control sites, restoration projects that remove Tamarix but do not assure replacement by high-quality native habitat have the potential to reduce the net riparian habitat value for some local or regional bird populations. Therefore, an assessment of potential negative impacts is important in deciding if exotic control should be conducted. In addition, measurable project objectives, appropriate control and restoration techniques, and robust monitoring are all critical to effective restoration planning and execution. ?? 2008 Society for Ecological Restoration International.

75 FR 8338 - EPA Science Advisory Board Staff Office Notification of a Meeting of the Ecological Effects...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-24

... the Second Section 812 Benefit-Cost Analysis of the Clean Air Act. The assessment of ecological... Analysis of the benefits and costs of the Clean Air Act. DATES: The EES augmented with additional experts... ecological effects of modeled air quality scenarios developed to support the Second Section 812 Benefit-Cost...

Determining significant endpoints for ecological risk analyses. 1997 annual progress report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hinton, T.G.; Congdon, J.; Rowe, C.

1997-11-01

'This report summarizes the first year''s progress of research funded under the Department of Energy''s Environmental Management Science Program. The research was initiated to better determine ecological risks from toxic and radioactive contaminants. More precisely, the research is designed to determine the relevancy of sublethal cellular damage to the performance of individuals and to identify characteristics of non-human populations exposed to chronic, low-level radiation, as is typically found on many DOE sites. The authors propose to establish a protocol to assess risks to non-human species at higher levels of biological organization by relating molecular damage to more relevant responses thatmore » reflect population health. They think that they can achieve this by coupling changes in metabolic rates and energy allocation patterns to meaningful population response variables, and by using novel biological dosimeters in controlled, manipulative dose/effects experiments. They believe that a scientifically defensible endpoint for measuring ecological risks can only be determined once its understood the extent to which molecular damage from contaminant exposure is detrimental at the individual and population levels of biological organization.'« less

Landscape of emerging and re-emerging infectious diseases in China: impact of ecology, climate, and behavior.

PubMed

Liu, Qiyong; Xu, Wenbo; Lu, Shan; Jiang, Jiafu; Zhou, Jieping; Shao, Zhujun; Liu, Xiaobo; Xu, Lei; Xiong, Yanwen; Zheng, Han; Jin, Sun; Jiang, Hai; Cao, Wuchun; Xu, Jianguo

2018-02-01

For the past several decades, the infectious disease profile in China has been shifting with rapid developments in social and economic aspects, environment, quality of food, water, housing, and public health infrastructure. Notably, 5 notifiable infectious diseases have been almost eradicated, and the incidence of 18 additional notifiable infectious diseases has been significantly reduced. Unexpectedly, the incidence of over 10 notifiable infectious diseases, including HIV, brucellosis, syphilis, and dengue fever, has been increasing. Nevertheless, frequent infectious disease outbreaks/events have been reported almost every year, and imported infectious diseases have increased since 2015. New pathogens and over 100 new genotypes or serotypes of known pathogens have been identified. Some infectious diseases seem to be exacerbated by various factors, including rapid urbanization, large numbers of migrant workers, changes in climate, ecology, and policies, such as returning farmland to forests. This review summarizes the current experiences and lessons from China in managing emerging and re-emerging infectious diseases, especially the effects of ecology, climate, and behavior, which should have merits in helping other countries to control and prevent infectious diseases.

Ecological restoration and effect investigation of a river wetland in a semi-arid region, China

NASA Astrophysics Data System (ADS)

Xu, S.; Jiang, X.; Liu, Y.; Fu, Y.; Zhao, Q.

2015-05-01

River wetlands are heavily impacted by human intervention. The degradation and loss of river wetlands has made the restoration of river ecosystems a top priority. How to rehabilitate rivers and their services has been a research focus. The main goal of it is to restore the river wetland ecosystems with ecological methods. The Gudong River was selected as a study site in Chaoyang city in this study. Based on the analysis of interference factors in the river wetland degradation, a set of restoration techniques were proposed and designed for regional water level control, including submerged dikes, ecological embankments, revegetation and dredging. The restoration engineering has produced good results in water quality, eco-environment, and landscape. Monthly reports of the Daling River show that the water quality of Gudong River was better than Grade III in April 2013 compared with Grade V in May 2012. The economic benefit after restoration construction is 1.71 million RMB per year, about 1.89 times that before. The ratio of economic value, social value and eco-environmental value is 1:4:23.

[Ecological risk assessment and its management of Bailongjiang watershed, southern Gansu based on landscape pattern].

PubMed

Gong, Jie; Zhao, Cai-Xia; Xie, Yu-Chu; Gao, Yan-Jing

2014-07-01

Watershed ecological risk assessment is an important research subject of watershed ecological protection and environmental management. Research on the ecological risk focuses on addressing the influence of human activities and its spatial variation at watershed scale is vital to policy-making to control the impact of human activity and protocols for sustainable economic and societal development. A comprehensive ecological environment index, incorporating a landscape index and an assessment of ecological vulnerability, was put forward to assess the spatio-temporal characteristics of ecological risk of the Bailongjiang watershed, southern Gansu Province, Northwest China. Using ArcGIS and Fragstats software and a land use map of 2010, an ecological risk map was obtained through spatial sampling and disjunctive Kriging interpolation. The results indicated that there were some obvious spatial differences of ecological risk levels in the watershed. The ecological risk level of the north and northwest of the Bailongjiang was higher than that of the western and southern extremities of the watershed. Ecological risk index (ERI) of Wudu and Tanchang was higher than that of Wenxian and Diebu. Some measures for ecological risk management were put forward on the basis of ERI of Bailongjiang watershed. To strengthen the integrated management of human activities and land use in the watershed, to carry out the vegetation restoration and ecological reconstruction, and to reduce the ecological risks and hazards of irrational human disturbance, are vital to the realization 'multiple-win' of the economic, social and ecological protection and for the sustainable development in the hilly area in southern Gansu.

Adopting an ecological view of metropolitan landscape: the case of "three circles" system for ecological construction and restoration in Beijing area.

PubMed

Zhang, Feng; Zhang, Xin-shi

2004-01-01

Ecological construction and restoration for sustainable development are now a driving paradigm. It is increasingly recognized that ecological principles, especially landscape ecology theory, are not only necessary but also essential to maintain the long-term sustainability worldwide. Key landscape ecology principles-element, structure and process, dynamics, heterogeneity, hierarchies, connectivity, place and time were reviewed, and use Beijing area as a case study to illustrate how these principles might be applied to ecological construction and restoration, to eventually achieve sustainability. An example to more effectively incorporate the ecological principles in sustainable planning in China was presented.

A Role for Ecological Restoration Work in University Environmental Education.

ERIC Educational Resources Information Center

Bowler, Peter A.; Kaiser, Florian G.; Hartig, Terry

1999-01-01

Studies the effects of ecological-restoration fieldwork and in-class instruction on students' ecological behavior, environmental attitudes, and perceptions of restorative qualities in a natural environment. (Author/CCM)

Migration-related detention centers: the challenges of an ecological perspective with a focus on justice.

PubMed

Esposito, Francesca; Ornelas, José; Arcidiacono, Caterina

2015-06-06

In recent years, border control and migration-related detention have become increasingly widespread practices affecting the lives of undocumented migrants, their families, and communities at large. In spite of the concern within academia, few studies have directly witnessed the life and experiences of people confined to migration-related detention centers. In the medical and psychological fields, a considerable body of research has demonstrated the pathogenic nature of detention in terms of mental health, showing an association between length of detention and severity of distress. Nevertheless, it was limited to the assessment of individuals' clinical consequences, mainly focusing on asylum seekers. There currently exists a need to adopt an ecological perspective from which to study detained migrants' experiences as context-dependent, and influenced by power inequalities. This paper addresses this gap. Drawing upon advances in community psychology, we illustrate an ecological framework for the study of migration-related detention contexts, and their effects on the lives of detained migrants and all people exposed to them. Making use of existing literature, Kelly's four principles (interdependence, cycling of resources, adaptation, succession) are analyzed at multiple ecological levels (personal, interpersonal, organizational, communal), highlighting implications for future research in this field. A focus on justice, as a key-dimension of analysis, is also discussed. Wellbeing is acknowledged as a multilevel, dynamic, and value-dependent phenomenon. In presenting this alternative framework, the potential for studying migration-related detention through an ecological lens is highlighted, pointing the way for future fields of study. We argue that ecological multilevel analyses, conceptualized in terms of interdependent systems and with a focus on justice, can enhance the comprehension of the dynamics at play in migration-related detention centers, providing an effective tool to address the multi-level challenges of doing research within them. Furthermore, they can contribute to the development of policies and practices concerned with health, equality, and human rights of all people exposed to migration-related detention. Consistent with these assumptions, empirical studies adopting such a framework are strongly encouraged. These studies should use mixed and multi-method culturally situated designs, based on the development of collaborative and empowering relationships with participants. Ethnographic approaches are recommended.

Ecological Network Analysis for a Low-Carbon and High-Tech Industrial Park

PubMed Central

Lu, Yi; Su, Meirong; Liu, Gengyuan; Chen, Bin; Zhou, Shiyi; Jiang, Meiming

2012-01-01

Industrial sector is one of the indispensable contributors in global warming. Even if the occurrence of ecoindustrial parks (EIPs) seems to be a good improvement in saving ecological crises, there is still a lack of definitional clarity and in-depth researches on low-carbon industrial parks. In order to reveal the processes of carbon metabolism in a low-carbon high-tech industrial park, we selected Beijing Development Area (BDA) International Business Park in Beijing, China as case study, establishing a seven-compartment- model low-carbon metabolic network based on the methodology of Ecological Network Analysis (ENA). Integrating the Network Utility Analysis (NUA), Network Control Analysis (NCA), and system-wide indicators, we compartmentalized system sectors into ecological structure and analyzed dependence and control degree based on carbon metabolism. The results suggest that indirect flows reveal more mutuality and exploitation relation between system compartments and they are prone to positive sides for the stability of the whole system. The ecological structure develops well as an approximate pyramidal structure, and the carbon metabolism of BDA proves self-mutualistic and sustainable. Construction and waste management were found to be two active sectors impacting carbon metabolism, which was mainly regulated by internal and external environment. PMID:23365516

Stochastic Community Assembly: Does It Matter in Microbial Ecology?

PubMed

Zhou, Jizhong; Ning, Daliang

2017-12-01

Understanding the mechanisms controlling community diversity, functions, succession, and biogeography is a central, but poorly understood, topic in ecology, particularly in microbial ecology. Although stochastic processes are believed to play nonnegligible roles in shaping community structure, their importance relative to deterministic processes is hotly debated. The importance of ecological stochasticity in shaping microbial community structure is far less appreciated. Some of the main reasons for such heavy debates are the difficulty in defining stochasticity and the diverse methods used for delineating stochasticity. Here, we provide a critical review and synthesis of data from the most recent studies on stochastic community assembly in microbial ecology. We then describe both stochastic and deterministic components embedded in various ecological processes, including selection, dispersal, diversification, and drift. We also describe different approaches for inferring stochasticity from observational diversity patterns and highlight experimental approaches for delineating ecological stochasticity in microbial communities. In addition, we highlight research challenges, gaps, and future directions for microbial community assembly research. Copyright © 2017 American Society for Microbiology.