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81.
This paper deals with the production of pollen grains per anther per flower of 15 probably allergenic pollen producing angiospermic
plant taxa growing in Eastern India. The selected plant taxa includesAilanthus excelsa, Alstonia scholaris, Argemone mexicana, Azadirachta indica, Cassia alata, C. siamea, Dalbergia sissoo, Holarrhena
pubescens, Lagerstroemia speciosa, Madhuca indica, Milletia pinnata, Mimusops elengi, Morus alba, M. indica andMurraya paniculata. Among the investigated taxa,A. excelsa produces the highest number of pollen grains (1635180) followed byC. siamea (1589245) andA. mexicana (463800). The production of pollen grains is lowest inH. pubescens (2500), followed byA. scholaris (5175),A. indica (6220) andM. paniculata (11200). 相似文献
82.
《Harmful algae》2014
The diel change in dissolved oxygen concentrations were recorded with an automated incubator containing a pulsed oxygen sensor in Sarasota Bay, Florida. The deployments occurred during a ‘pre-bloom’ period in May to June 2006, and during a harmful algal bloom dominated by Karenia brevis in September 2006. The diurnal (daylight) increase in dissolved oxygen concentrations varied from 16 to 104 μmol O2 l−1 with the corresponding nocturnal decrease in oxygen varying from 16 to 77 μmol O2 l−1. Nocturnal respiration consumed 42–113% of the diurnal net oxygen production with the minimum and maximum during the pre-bloom period. Hourly production rates closely followed fluctuations in irradiance with maximum rates in the late morning. Hourly oxygen utilization rates (community respiration) at night were highest during the first few hours after sunset. 相似文献
83.
R. Lefébure R. Degerman A. Andersson S. Larsson L‐O. Eriksson U. Båmstedt P. Byström 《Global Change Biology》2013,19(5):1358-1372
Both temperature and terrestrial organic matter have strong impacts on aquatic food‐web dynamics and production. Temperature affects vital rates of all organisms, and terrestrial organic matter can act both as an energy source for lower trophic levels, while simultaneously reducing light availability for autotrophic production. As climate change predictions for the Baltic Sea and elsewhere suggest increases in both terrestrial matter runoff and increases in temperature, we studied the effects on pelagic food‐web dynamics and food‐web efficiency in a plausible future scenario with respect to these abiotic variables in a large‐scale mesocosm experiment. Total basal (phytoplankton plus bacterial) production was slightly reduced when only increasing temperatures, but was otherwise similar across all other treatments. Separate increases in nutrient loads and temperature decreased the ratio of autotrophic:heterotrophic production, but the combined treatment of elevated temperature and terrestrial nutrient loads increased both fish production and food‐web efficiency. CDOM: Chl a ratios strongly indicated that terrestrial and not autotrophic carbon was the main energy source in these food webs and our results also showed that zooplankton biomass was positively correlated with increased bacterial production. Concomitantly, biomass of the dominant calanoid copepod Acartia sp. increased as an effect of increased temperature. As the combined effects of increased temperature and terrestrial organic nutrient loads were required to increase zooplankton abundance and fish production, conclusions about effects of climate change on food‐web dynamics and fish production must be based on realistic combinations of several abiotic factors. Moreover, our results question established notions on the net inefficiency of heterotrophic carbon transfer to the top of the food web. 相似文献
84.
85.
EMANUELA BAZZONI GIOVANNI SANNA PASSINO MARIO D L MORETTI ROMOLO PROTA 《The Annals of applied biology》1997,131(3):369-374
We report the effects of anethole on adult Ceratitis capitata Wied. (Diptera, Tephritidae) which cause serious damage to fruit crops. Because of the toxicological and environmental pollution due to the indiscriminate use of organophosphates against the endophagous larvae, the control of this pest is now mainly directed against the adults, by the application of bait sprays. Considerable toxic effects have been obtained by oral administration to adults of nutritive formulations containing 5% anethole with some hydrolised commercial proteins. In this test we observed high values of mortality (85% after 24 h) and a total inhibition of reproductive activity. The toxic effect produced by oral administration of the compound tested appears to be correlated to irreversible damage to the gut of the medfly. These results acquire a particular importance in view of the introduction of alternative methods for the control of the medfly. In particular, our objective is the testing of relevant formulations of this active principle in field. The use of anethole combined with protein baits, which can be used in the open field, is therefore particularly promising. 相似文献
86.
Von Hippel and colleagues have highlighted the crucial role of users in innovation in different industries and types of products. They describe the innovation process in terms of the distinct domains of knowledge that producers and users possess. Producers have knowledge about technical solutions and users about their needs, the context of use, and their own capabilities as users. Both sets of knowledge are characterized by "stickiness": They move relatively freely within their own domain but are difficult to transfer outside of it.
In the case of radical innovations for sustainable consumption, the problem of "sticky information" is compounded. Both producers and consumers need to reach out of their conventional competencies and search for new solutions. "Societal actors," such as government bodies or environmental experts, can show the way to such solutions, but this new knowledge needs to be integrated with the "sticky" knowledge about everyday practices in production and consumption.
In the present article we attempt to conceptualize the role and interaction of user and producer knowledge with the knowledge of environmental experts in housing energy innovations. We do so by applying the user−producer interaction framework to a case study on the introduction of low-energy housing concepts in Finland. On the basis of this analysis, we draw conclusions on the potential and limitations of today's practices in the field. For example, we suggest that user involvement can help to enhance the acceptance of low-energy solutions but that the methods for involving users need to be adapted to the particular circumstances in each industry. 相似文献
In the case of radical innovations for sustainable consumption, the problem of "sticky information" is compounded. Both producers and consumers need to reach out of their conventional competencies and search for new solutions. "Societal actors," such as government bodies or environmental experts, can show the way to such solutions, but this new knowledge needs to be integrated with the "sticky" knowledge about everyday practices in production and consumption.
In the present article we attempt to conceptualize the role and interaction of user and producer knowledge with the knowledge of environmental experts in housing energy innovations. We do so by applying the user−producer interaction framework to a case study on the introduction of low-energy housing concepts in Finland. On the basis of this analysis, we draw conclusions on the potential and limitations of today's practices in the field. For example, we suggest that user involvement can help to enhance the acceptance of low-energy solutions but that the methods for involving users need to be adapted to the particular circumstances in each industry. 相似文献
87.
Bruce D. Smith 《Evolutionary anthropology》2007,16(5):188-199
Many animal species attempt to enhance their environments through niche construction or environmental engineering. Such efforts at environmental modification are proposed to play an important and underappreciated role in shaping biotic communities and evolutionary processes. 1 , 2 Homo sapiens is acknowledged as the ultimate niche constructing species in terms of our rich repertoire of ecosystem engineering skills and the magnitude of their impact. We have been trying to make the world a better place—for ourselves—for tens of thousands of years. I argue here that it is within this general context of niche‐construction behavior that our distant ancestors initially domesticated plants and animals and, in the process, first gained the ability to significantly alter the world's environments. The general concept of niche construction also provides the logical link between current efforts to understand domestication being conducted at two disconnected scales of analysis. At the level of individual plant and animal species, on one hand, there recently have been significant advances in our knowledge of the what, when, and where of domestication of an ever‐increasing number of species worldwide. 3 At the same time, large‐scale regional or universal developmental models of the transition to food production continue to be formulated. These incorporate a variety of “macro‐evolutionary” causal variables that may account for why human societies first domesticated plants and animals. 4 , 5 This essay employs the general concept of niche construction to address the intervening question of how, and to connect these two scales of analysis by identifying the general behavioral context within which human societies responded to “macroevolutionary” causal variables and forged new human plant or animal relationships of domestication. 相似文献
88.
David J. Ballantyne 《Phytochemistry》1973,12(6):1207-1209
Adenosine triphosphate production in mitochondria of bean hypocotyls and maize coleoptiles is inhibited by sulphite. Oxidized glutathione decreases the inhibition, probably by reducing the sulphite concentration in the reaction mixture. 相似文献
89.
《Animal : an international journal of animal bioscience》2021,15(7):100247
Demand for beef produced from pasture-based diets is rising as it is perceived to be healthier, animal friendly and good for the environment. Animals reared on a solely grass forage diet, however, have a lower growth rate than cereal-fed animals and consequently are slaughtered at an older age. This study focused on the former by conducting life cycle assessments of beef production systems offering only fresh or conserved grass, and comparing them to a conventional pasture-based beef production system offering concentrate feeding during housing. The four suckler weanling-to-beef production systems simulated were: (i) Steers produced to slaughter entirely on a grass forage diet at 20 months (GO-20); (ii) Steers produced to slaughter entirely on a grass forage diet at 24 months (GO-24); (iii) Steers produced to slaughter on a grass forage diet with concentrate supplementation during housing (GC-24), and (iv) Steers produced to slaughter entirely on a grass forage diet at 28 months (GO-28). Two breed types were evaluated: early-maturing and late-maturing (LM). The environmental impacts assessed were global warming potential (GWP), non-renewable energy (NRE), acidification potential (AP), eutrophication potential (marine (MEP) and freshwater) were expressed per animal, per kg live weight gain (LWG), kg carcass weight gain, and kg meat weight gain (MWG). The GO-20 production system had the lowest environmental impact across all categories and functional units for both breeds. Extending age at slaughter increased environmental impact across all categories per animal. The LWG response of EM steers to concentrate feed supplementation in GC-24 was greater than the increase in total environmental impact resulting in GC-24 having a lower environmental impact across categories per kg product than GO-24. Concentrate feed supplementation had a similar effect on LM steers with the exception of NRE and AP. The increase in daily LWG in the third grazing season in comparison to the second grazing and housing resulted in GO-28 having lower GWP, NRE, AP, and MEP per kg product than GO-24. Early-maturing steers had lower environmental impact than LM when expressed per kg LWG. However the opposite occurred when impacts were expressed per kg MWG, despite LM steers producing the least LWG. The LM steers compensated for poor LWG performance by having superior carcass traits, which caused the breed to have the lowest environmental impact per kg MWG. The results reaffirms the importance of functional unit and suggests reducing the environmental impact of LWG does not always translate into improvements in the environmental performance of meat. 相似文献
90.