Hasil untuk "Ecology"

P. Gobster, J. Nassauer, T. Daniel et al.

J. Prosser, B. Bohannan, T. Curtis et al.

J. Krebs, N. Davies

M. Turner

P. Morin, G. Luikart, R. Wayne

T. Forsyth

Gregory A. Cajete

C. Heip, M. Vincx, G. Vranken

F. Bazzaz

J. P. Grime, J. Hodgson, R. Hunt

R. Fisher, D. Binkley

Forest soils have characteristic properties that set them apart from the usual types of soils used for growing crops. Often rocky, of poor quality, and in mountainous terrain, forest soils are nevertheless the foundation of the entire forest ecosystem, supporting a diverse assemblage of plants and animals. They are often fragile soils, easily subject to erosion by road building or logging operation. A proper understanding of forest soils is an essential component of understanding forest ecology and maintaining the diversity and productivity of forested land. This new edition emphasizes the ecological aspects of forest soils. It is global in its scope, discussing soil types ranging from the tropical rainforest soils of Latin America to the boreal forest soils of Siberia. Separate chapters discuss the physical, chemical, and biological aspects of forest soils, with additional chapters on soil organic matter, roots, and biogeochemistry. It highlights the site specific factors that are important in each case and discusses practical management aspects including: nutrition management, thinning, site preparation techniques, soils for nursery and seed orchard operation, problem soils, atmospheric deposition of nutrients, soil acidity, and techniques for sustaining and improving long term soil productivity.

M. Alberti, J. Marzluff, E. Shulenberger et al.

L. V. Lier

G. Huse

W. Adams, J. Hutton

Philip S. Corbet

W. Karesh, A. Dobson, J. Lloyd-Smith et al.

Summary More than 60% of human infectious diseases are caused by pathogens shared with wild or domestic animals. Zoonotic disease organisms include those that are endemic in human populations or enzootic in animal populations with frequent cross-species transmission to people. Some of these diseases have only emerged recently. Together, these organisms are responsible for a substantial burden of disease, with endemic and enzootic zoonoses causing about a billion cases of illness in people and millions of deaths every year. Emerging zoonoses are a growing threat to global health and have caused hundreds of billions of US dollars of economic damage in the past 20 years. We aimed to review how zoonotic diseases result from natural pathogen ecology, and how other circumstances, such as animal production, extraction of natural resources, and antimicrobial application change the dynamics of disease exposure to human beings. In view of present anthropogenic trends, a more effective approach to zoonotic disease prevention and control will require a broad view of medicine that emphasises evidence-based decision making and integrates ecological and evolutionary principles of animal, human, and environmental factors. This broad view is essential for the successful development of policies and practices that reduce probability of future zoonotic emergence, targeted surveillance and strategic prevention, and engagement of partners outside the medical community to help improve health outcomes and reduce disease threats.

A. Barata, M. Malfeito-Ferreira, V. Loureiro

Fanglan Wu, Yunxiao Zhao, Yicun Chen et al.

Flavonoids are not only widely applied in the food, pharmaceutical and cosmetic industries, but also possess diverse biological functions that play crucial roles in plant physiology, growth and development, and ecology. The camphor tree (Cinnamomum camphora (L.)) holds significant economic and ecological value; however, its flavonoid composition and the underlying biosynthetic mechanisms remain largely unexplored. In this study, widely targeted metabolomics and transcriptomics were integrated to comprehensively analyze the leaves of C. camphora. The results revealed significant metabolic differences among fresh leaves of different C. camphora chemotypes. with both DAMs and DEGs being significantly enriched in the flavonoid biosynthesis pathway. Quercetin-5-O-glucuronide, rhamnetin-3-O-glucoside, juglanin, catechin and (-)-epicatechin were identified as the major DAMs. Furthermore, the key enzymes involved in the flavonoid biosynthetic pathway, such as PAL, C4H, and 4CL, CHS, CHI, F3H, FLS, DFR, ANS, LAR, C3H, and HCT were identified. Among these, CcC4H1 was identified as a hub gene in co-expression network. Compared with the control, transient overexpression of CcC4H1 significantly increased the total flavonoid content in C. camphora leaves by 1.45-fold (reaching 2.42 mg/g), while significantly elevating the flavonoids compounds such as 8-C-methylquercetin 3-xyloside, 2-(3,4-dihydroxyphenyl)-5,7-dihydroxy-3-[(2S,3S,4 R,5S,6 R)-2,3,5-trihydroxy-6-methyloxan-4-yl]oxychromen-4-one, and rhamnetin-3-O-glucoside, with increases ranging from 1.88- to 22.79-fold. These findings provide important insights into the molecular regulation mechanisms of flavonoid biosynthesis in camphor trees and provide important information for the selection of varieties rich in flavonoids.

Aparna Mariyam Thomas, Guilherme G. Verocai, John Soghigian et al.

The caribou (Rangifer tarandus sspp.) is a keystone wildlife species in northern ecosystems that plays a central role in the culture, spirituality and food security of Indigenous People. The Arctic is currently experiencing an unprecedented rate of climate change, including warming temperatures and altered patterns of precipitation. These environmental changes can facilitate the transmission of arthropod-borne parasites, such as filarioid nematodes.Filarioids are an important cause of morbidity and occasional mortality in Rangifer in Fennoscandia, however, much of the ecology and epidemiology of these parasites in caribou in North America, including Canada, remains unknown. We aimed to determine the parasitic diversity and geographic distribution of filarioid nematodes in three Canadian designatable units (DU) of caribou (barren-ground, boreal and Dolphin & Union) from Northwest Territories, Nunavut and Newfoundland & Labrador. Genomic DNA extracted from 768 blood samples was screened for filarioid nematodes using real-time PCR. The positive samples were Sanger sequenced to identify the parasite present. Based on the sequencing results, we identified Setaria yehi and Onchocerca cervipedis s.l. We then standardized a TaqMan probe based duplex droplet digital PCR (ddPCR) protocol for the simultaneous detection of S. yehi and O. cervipedis s.l. Based on real-time PCR results, 8/768 samples were positive. Setaria yehi and O. cervipedis s.l. were present in 4 separate samples (0.5%) each. Using ddPCR, 68/192 samples were positive (35.4%). Setaria yehi DNA was detected in 57/192 positive samples (29.7%), O. cervipedis s.l. DNA was present in 22/192 samples (11.5%) and 11/192 samples (5.7%) had co-infections. Setaria yehi was detected in all three DUs tested. Onchocerca cervipedis s.l. were found in barren-ground and boreal caribou, but not from the Dolphin and Union caribou.Through this broad-based survey and through developing and implementing advanced molecular methodologies, we have documented the apparent distribution and diversity of S. yehi and O. cervipedis s.l. in parts of three Canadian DUs of caribou. The knowledge gained from this study provides baseline data and methodology for the further elucidation of the epidemiology of these parasites in North America.