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491.
Workers never mate in the large majority of ants, and they have usually lost the spermatheca, an organ specialized for long-term
storage of sperm. Such ‘non-sexual’ workers are restricted to laying unfertilized eggs that give rise to males, and they cannot
compete with the queens for the production of female offspring. In sharp contrast, workers in 200–300 species from phylogenetically
basal subfamilies can reproduce sexually (‘gamergates’) because they retain a functional spermatheca like the queens. Importantly,
‘non-sexual’ workers in closely related species have a vestigial spermatheca. In this study, we compared the reservoir epithelium
of ‘sexual’ workers to that of congeneric queens and ‘non-sexual’ workers using 21 species of Amblyoponinae, Ponerinae and
Ectatomminae. We show that a pronounced thickening of the epithelium near the opening of the sperm duct is strictly associated
with sexual reproduction in both castes. This is unlike ‘non-sexual’ workers in which this epithelium is always very thin,
with few organelles; but all other structures remain intact. We discuss this evolutionary degeneration of the spermatheca
and how it relates to behavioural or physiological modifications linked to mating. Our results help understand the loss of
sexual reproduction by ant workers, a critical step in the extreme specialization of their phenotype. 相似文献
492.
Manuel R. Guariguata Jonathan P. Cornelius Bruno Locatelli Claudio Forner G. Arturo Sánchez-Azofeifa 《Mitigation and Adaptation Strategies for Global Change》2008,13(8):793-808
The relationship between tropical forests and global climate change has so far focused on mitigation, while much less emphasis
has been placed on how management activities may help forest ecosystems adapt to this change. This paper discusses how tropical
forestry practices can contribute to maintaining or enhancing the adaptive capacity of natural and planted forests to global
climate change and considers challenges and opportunities for the integration of tropical forest management in broader climate
change adaptation. In addition to the use of reduced impact logging to maintain ecosystem integrity, other approaches may
be needed, such as fire prevention and management, as well as specific silvicultural options aimed at facilitating genetic
adaptation. In the case of planted forests, the normally higher intensity of management (with respect to natural forest) offers
additional opportunities for implementing adaptation measures, at both industrial and smallholder levels. Although the integration
in forest management of measures aimed at enhancing adaptation to climate change may not involve substantial additional effort
with respect to current practice, little action appears to have been taken to date. Tropical foresters and forest-dependent
communities appear not to appreciate the risks posed by climate change and, for those who are aware of them, practical guidance
on how to respond is largely non-existent. The extent to which forestry research and national policies will promote and adopt
management practices in order to assist production forests adapt to climate change is currently uncertain. Mainstreaming adaptation
into national development and planning programs may represent an initial step towards the incorporation of climate change
considerations into tropical forestry. 相似文献
493.
Jean-Luc Boudenne Julien Parinet Carine Demelas Tarek Manasfi Bruno Coulomb 《环境科学学报(英文版)》2017,29(8):262-270
Water and air quality of eight seawater swimming pools using chlorine disinfection was measured during four sampling campaigns, spread on one full-year, and in four thalassotherapy centers located in Southeast of France. Concentrations of trihalomethanes(THMs) in air and in water as well as concentrations of parameters, including nonpurgeable organic carbon(NPOC), free residual chlorine(Cl_f), pH, Kjeldhal Nitrogen(KN), salinity,conductivity, bromide ions and, water and air temperature, were measured. Water and air samples were collected in triplicates morning — at the opening of the pools —, noon and night — at the closing of the pools —, in summer and winter. Data analysis was performed by Principal Component Analysis(PCA) and rotated component matrix, from both data quality and other parameters such as TOC, aromaticity(UV_(254)), pH, hygrometry, and free residual chlorine(Cl_f). This statistical analysis demonstrates a high correlation between TOC, Cl_fand UV_(254) and THM levels found in air and water, particularly for the major ones(CHBr_3in water:300.0 μg/L mean, 1029.0 μg/L maximum; CHBr_3 in air: 266.1 μg/m~3 mean,1600.0 μg/m~3 maximum, and CHClBr_2 in water: 18.9 μg/L mean, 81.0 μg/L maximum;CHClBr_2 in air: 13.6 μg/m~3 mean, 150.0 μg/m~3maximum). These high levels of bromoform(CHBr_3) are particularly worrisome in such health institutions, even these levels do not exceed the Permissible Exposure Limit(PEL) of 5 mg/m~3 as an 8 hour time-weighted average currently fixed by various administrations, such as Occupational Safety and Health Administration(OSHA). 相似文献
494.
Houria Djoudi Bruno Locatelli Catherine Pehou Matthew J. Colloff Marlne Elias Denis Gautier Russell Gorddard Barbara Vinceti Mathurin Zida 《Ambio》2022,51(10):2137
Indigenous trees play key roles in West African landscapes, such as the néré tree (Parkia biglobosa (Jacq.) R.Br. ex G.Don). We applied social–ecological network analysis to understand the social–ecological interactions around néré. We documented the benefits néré provides and the multiple social interactions it creates amongst a large range of actors. The flows of rights over the trees and benefits from them formed two hierarchical networks, or cascades, with different actors at the top. The two forms of power revealed by the two cascades of rights and benefits suggest possible powers and counter-powers across gender, ethnicity, and age. We documented how the tree catalyses social interactions across diverse groups to sustain vital social connections, and co-constitute places, culture, and relationships. We argue that a paradigm shift is urgently needed to leverage the remarkable untapped potential of indigenous trees and Cultural Keystone Species in current global restoration and climate change agendas.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-022-01733-z. 相似文献
495.
Hollas Camila Ester Rodrigues Heloisa Campeão Oyadomari Vitoria Mitsue Agliardi Bolsan Alice Chiapetti Venturin Bruno Bonassa Gabriela Tápparo Deisi Cristina Abilhôa Hélen Caroline Zonta da Silva João Fernando Ferri Michelon William Cavaler Jadiane Paola Antes Fabiane Goldschmidt Steinmetz Ricardo Luís Radis Treichel Helen Kunz Airton 《Environmental science and pollution research international》2022,29(49):73599-73621
Environmental Science and Pollution Research - Improper disposal of animal waste is responsible for several environmental problems, causing eutrophication of lakes and rivers, nutrient overload in... 相似文献
496.
de Araújo Gusmão Carolina Palharim Priscila Hasse Ramos Bruno Teixeira Antonio Carlos Silva Costa 《Environmental science and pollution research international》2022,29(28):42215-42230
Environmental Science and Pollution Research - Catalyst samples based on SiO2-supported TiO2 were prepared with the incorporation of Ag (metal), S (nonmetal), and ZnO@S (semiconductor and... 相似文献
497.
Punzo Gennaro Castellano Rosalia Bruno Emma 《Environmental and Ecological Statistics》2022,29(4):727-753
Environmental and Ecological Statistics - This study sets up a spatial econometric framework to explore the factors that best describe land consumption in Italy at the municipal level. By modelling... 相似文献
498.
Punzo Gennaro Castellano Rosalia Bruno Emma 《Environmental and Ecological Statistics》2022,29(4):915-926
Environmental and Ecological Statistics - 相似文献
499.
da Silva Barbosa Ferreira Eduardo Luna Carlos Bruno Barreto Siqueira Danilo Diniz Araújo Edcleide Maria de França Danyelle Campos Wellen Renate Maria Ramos 《Journal of Polymers and the Environment》2022,30(2):541-554
Journal of Polymers and the Environment - PLA has aroused industrial and scientific interest in recent years, mainly due to its biodegradable character. However, PLA is brittle and displays low... 相似文献