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11.
12.
Hannah K. Larson Shana K. Goffredi Erica L. Parra Orlando Vargas Adrián A. Pinto-Tomas Terrence P. McGlynn 《Die Naturwissenschaften》2014,101(5):397-406
We document a facultative Bartonella-like Rhizobiales bacterium in the giant tropical ant, Paraponera clavata. In a lowland tropical rainforest in Costa Rica, 59 colonies were assayed for the prevalence of the Bartonella-like bacterium (BLB), 14 of which were positive. We addressed three questions: First, how does the prevalence of BLB within colonies vary with environmental conditions? Second, how does diet affect the prevalence of BLB in P. clavata? Third, how does the distribution of BLB among colonies reflect ambient differences in food resources and foraging habits? A variety of environmental variables that may be predictive of the presence of BLB were measured, and diet manipulations were conducted to test whether the prevalence of BLB responded to supplemental carbohydrate or prey. The ambient frequency of BLB is much higher in young secondary forests, but is nearly absent from older secondary forests. The prevalence of BLB inside field colonies increased over the duration of a 2-week carbohydrate supplementation; however, water and prey supplementation did not alter the prevalence of BLB. The diets of the colonies located in young secondary forest, compared to other habitats, have a diet richer in carbohydrates and lower in prey. The abundance of carbohydrate, or the relative lack of N, in a colony’s diet influences the occurrence of the BLB microbe in P. clavata. As experimental diet manipulations can affect the facultative presence of an N-cycling microbe, a consistent diet shift in diet may facilitate the emergence of tighter symbioses. 相似文献
13.
14.
Conti Marcelo Enrique Plà Rita Simone Cristina Jasan Raquel Finoia Maria Grazia 《Environmental science and pollution research international》2020,27(31):38819-38834
Environmental Science and Pollution Research - This study aims to investigate the airborne elements’ deposition by using native Usnea barbata lichens as biomonitors in the forested areas of... 相似文献
15.
Yoram Tencer Gil Idan Marjorie Strom Uri Nusinow Dorit Banet Eli Cohen Peter Schröder Oren Shelef Shimon Rachmilevitch Ines Soares Amit Gross Avi Golan-Goldhirsh 《Environmental science and pollution research international》2009,16(7):862-875
Background, aim, and scope
The project was set to construct an extensive wetland in the southernmost region of Israel at Kibbutz Neot Smadar (30°02′45″ N and 35°01′19″ E). The results of the first period of monitoring, summary, and perspectives are presented. The constructed wetland (CW) was built and the subsequent monitoring performed in the framework of the Southern Arava Sustainable Waste Management Plan, funded by the EU LIFE Fund. The specific aims were: (1) To end current sewage disposal and pollution of the ground, the aquifer, and the dry river bed (wadi) paths by biologically treating the sewage as part of the creation of a sustainable wetland ecosystem. (2) Serve as an example of CW in the Negev highlands and the Arava Valley climates for neighboring communities and as a test ground for plants and building methods appropriate to hyper arid climate. (3) Serve as an educational resource and tourist attraction for groups to learn about water reuse, recycling, local wildlife and migrating birds, including serving the heart of a planned Ecological–Educational Bird Park. This report is intended to allow others who are planning similar systems in hyper arid climates to learn from our experience.Materials and methods
The project is located in an extreme arid desert with less than 40 mm of rain annually and temperature ranges of ?5°C to +42°C. The site receives 165–185 m3 of municipal and agricultural wastes daily, including cowshed and goat wastes and winery outflow.Results
The CW establishment at Neot Smadar was completed in October 2006. For 8 months, clean water flowed through the system while the plants were taking root. In June 2007, the wetland was connected to the oxidation pond and full operation began. Because of seepage and evaporation, during the first several months, the water level was not high enough to allow free flow from one bed to the next. To bed A, the water was pumped periodically from the oxidation pond (Fig. 1) and from there flowed by gravitation through the rest of the system. The initial results of the monitoring are promising. In nearly all measurements, the system succeeded as expected to reduce levels of contaminants at least to the level acceptable for irrigating fruit trees and often to the level of unlimited irrigation. The introduction of the plants in the system and their physiological performance were evaluated and were found to correlate well to the quality of water in the various beds.Discussion
It should be said at the outset that evaluation of the performance of a CW system is a long-term process. Thus, the main aim of this report is to present the problems, difficulties, preliminary results, and concepts concerned with the first stage of establishment of CW in an extremely dry region.Conclusions
The CW system was designed to dispose of municipal and agricultural wastes in a way that not merely reduces pollution, but adds to environmental quality by creating accessible parkland for local residents and tourists. Several factors affected the performance of the system at the initial stages of operation: ecological balance between microbes and plants, big seasonal variations, seepage and evaporation reduced the flow in the initial operation of the system. Despite the initial difficulties, the quality of water coming out the system is acceptable for irrigation.Recommendations and perspectives
The CW can function well under extreme dryland conditions. The oxidation pond was the major source of evaporation and bad odors. Therefore, alternatives to the oxidation pond are needed. Cost effectiveness of the system still has to be evaluated systematically. 相似文献16.
Franck L. B. Meijboom Nina Cohen Elsbeth N. Stassen Frans W. A. Brom 《Journal of Agricultural and Environmental Ethics》2009,22(6):559-571
European animal disease policy seems to find its justification in a “harm to other” principle. Limiting the freedom of animal
keepers—e.g., by culling their animals—is justified by the aim to prevent harm, i.e., the spreading of the disease. The picture,
however, is more complicated. Both during the control of outbreaks and in the prevention of notifiable, animal diseases the
government is confronted with conflicting claims of stakeholders who anticipate running a risk to be harmed by each other, and who ask for government intervention. In this paper, we first argue that in a policy that
aims to prevent animal diseases, the focus shifts from limiting “harm” to weighing conflicting claims with respect to “risks
of harm.” Therefore, we claim that the harm principle is no longer a sufficient justification for governmental intervention
in animal disease prevention. A policy that has to deal with and distribute conflicting risks of harm needs additional value
assumptions that guide this process of assessment and distribution. We show that currently, policies are based on assumptions
that are mainly economic considerations. In order to show the limitations of these considerations, we use the interests and
position of keepers of backyard animals as an example. Based on the problems they faced during and after the recent outbreaks,
we defend the thesis that in order to develop a sustainable animal disease policy other than economic assumptions need to
be taken into account. 相似文献
17.
Nina E. Cohen Frans W. A. Brom Elsbeth N. Stassen 《Journal of Agricultural and Environmental Ethics》2009,22(4):341-359
In this paper, we present and defend the theoretical framework of an empirical model to describe people’s fundamental moral
attitudes (FMAs) to animals, the stratification of FMAs in society and the role of FMAs in judgment on the culling of healthy
animals in an animal disease epidemic. We used philosophical animal ethics theories to understand the moral basis of FMA convictions.
Moreover, these theories provide us with a moral language for communication between animal ethics, FMAs, and public debates.
We defend that FMA is a two-layered concept. The first layer consists of deeply felt convictions about animals. The second
layer consists of convictions derived from the first layer to serve as arguments in a debate on animal issues. In a debate,
the latter convictions are variable, depending on the animal issue in a specific context, time, and place. This variability
facilitates finding common ground in an animal issue between actors with opposing convictions. 相似文献
18.
19.
Sónia R. Q. Serra Ana Raquel Calapez Amaia Pérez-Bilbao Maria João Feio 《Environmental monitoring and assessment》2015,187(1):1-13
Bioassessment tools should distinguish between the effects of anthropogenic degradation in communities and natural temporal changes. The present study tests the influence of natural seasonal variability on macroinvertebrate stream communities assessed by a predictive model (PORTRIV) and a multimetric index (IPtI) calibrated for spring. The scores of PORTRIV decreased significantly between spring and autumn, and between spring and winter (ca. 37 to 53 %, respectively), while those of IPtI did not change significantly between seasons. For non-reference samples, the results of the predictive model also indicate no significant differences. A correction factor (CF) was calculated to adjust the existing differences in the model assessments between seasons, based on the percentage of variation of reference site scores from spring to autumn and winter. After the application of the CF to the OE50 scores of spring reference samples, the differences were no longer significant. Independent reference validation sites confirmed this tendency. This method has the advantage of avoiding large efforts required for the construction of databases from other seasons and the development of new models to allow the assessment of streams in seasons other than spring. Further tests with models developed in regions with more marked seasonal changes should be done to confirm its wider applicability. 相似文献
20.
de Figueiredo DR Ferreira RV Cerqueira M de Melo TC Pereira MJ Castro BB Correia A 《Environmental monitoring and assessment》2012,184(1):471-485
The information on bacterial community composition (BCC) in Portuguese water bodies is very scarce. Cértima River (central
western Portugal) is known to have high levels of pollution, namely organic. In the present work, the BCC from a set of 16
water samples collected from Cértima River Basin and its main tributaries was characterized using 16S rDNA–denaturing gradient
gel electrophoresis, a culture-independent molecular approach. Molecular data were related to environmental parameters through
multivariate analysis to investigate potential impact of water pollution along the river. Principal component analysis using
environmental data showed a water quality gradient from more pristine waters (at the mountain tributaries) to waters with
increasingly eutrophic potential (such as Fermentelos Lake). This gradient was mainly defined by factors such as organic and
inorganic nutrient sources, electrical conductivity, hydrogen carbonate concentration, and pH. Molecular results showed variations
in BCC along Cértima River Basin but in the main river section, a Bacteroidetes phylotype (Flavobacterium sp.) proved to be dominant throughout the river course. Multivariate analysis suggests that spatial variation of BCC along
the Cértima River Basin depended mainly on parameters such as Chl a, total suspended solid (TSS), total organic carbon, electrical conductivity, and HCO
_boxclose^-_{3}^{-} levels. Bacteroidetes phylotypes were all related to higher electrical conductivity and HCO3-_{3}^{-} levels although some of these were also correlated with high SO42-_{4}^{2-} and others with high soluble reactive phosphorus, nitrate, TN, and Kjeld-N levels. The Gammaproteobacteria occurrence was correlated with high SO42-_{4}^{2-} levels. One of the Betaproteobacteria phylotypes showed to correlate with low redox potential (Eh) and high temperature, pH, TSS, and Chl a levels while another one showed a negative correlation with Chl a values. 相似文献