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排序方式: 共有211条查询结果,搜索用时 15 毫秒
1.
Erik Joaquín Torres-Romero Vincent Nijman David Fernández Timothy M. Eppley 《Global Change Biology》2023,29(20):5775-5787
The world's primates have been severely impacted in diverse and profound ways by anthropogenic pressures. Here, we evaluate the impact of various infrastructures and human-modified landscapes on spatial patterns of primate species richness, at both global and regional scales. We overlaid the International Union for the Conservation of Nature (IUCN) range maps of 520 primate species and applied a global 100 km2 grid. We used structural equation modeling and simultaneous autoregressive models to evaluate direct and indirect effects of six human-altered landscapes variables (i.e., human footprint [HFP], croplands [CROP], road density [ROAD], pasture lands [PAST], protected areas [PAs], and Indigenous Peoples' lands [IPLs]) on global primate species richness, threatened and non-threatened species, as well as on species with decreasing and non-decreasing populations. Two-thirds of all primate species are classified as threatened (i.e., Critically Endangered, Endangered, and Vulnerable), with ~86% experiencing population declines, and ~84% impacted by domestic or international trade. We found that the expansion of PAST, HFP, CROP, and road infrastructure had the most direct negative effects on primate richness. In contrast, forested habitat within IPLs and PAs was positively associated in safeguarding primate species diversity globally, with an even stronger effect at the regional level. Our results show that IPLs and PAs play a critical role in primate species conservation, helping to prevent their extinction; in contrast, HFP growth and expansion has a dramatically negative effect on primate species worldwide. Our findings support predictions that the continued negative impact of anthropogenic pressures on natural habitats may lead to a significant decline in global primate species richness, and likely, species extirpations. We advocate for stronger national and international policy frameworks promoting alternative/sustainable livelihoods and reducing persistent anthropogenic pressures to help mitigate the extinction risk of the world's primate species. 相似文献
2.
Taiye Winful Katie McCormack Elsa Mueller Lijuan Chen La Corporación Piñones Se Integra Maricruz Rivera Clemente Jada Benn Torres 《American journal of physical anthropology》2023,182(2):194-209
Objectives
From an anthropological genetic perspective, little is known about the ethnogenesis of African descendants in Puerto Rico. Furthermore, historical interactions between Indigenous Caribbean and African descendant peoples that may be reflected in the ancestry of contemporary populations are understudied. Given this dearth of genetic research and the precedence for Afro-Indigenous interactions documented by historical, archeological, and other lines of evidence, we sought to assess the biogeographic origins of African descendant Puerto Ricans and to query the potential for Indigenous ancestry within this community.Materials and Methods
Saliva samples were collected from 58 self-identified African descendant Puerto Ricans residing in Puerto Rico. We sequenced whole mitochondrial genomes and genotyped Y chromosome haplogroups for each male individual (n = 25). Summary statistics, comparative analyses, and network analysis were used to assess diversity and variation in haplogroup distribution between the sample and comparative populations.Results
As indicated by mitochondrial haplogroups, 66% had African, 5% had European, and 29% had Indigenous American matrilines. Along the Y chromosome, 52% had African, 28% had Western European, 16% had Eurasian, and, notably, 4% had Indigenous American patrilines. Both mitochondrial and Y chromosome haplogroup frequencies were significantly different from several comparative populations.Discussion
Biogeographic origins are consistent with historical accounts of African, Indigenous American, and European ancestry. However, this first report of Indigenous American paternal ancestry in Puerto Rico suggests distinctive features within African descendant communities on the island. Future studies expanding sampling and incorporating higher resolution genetic markers are necessary to more fully understand African descendant history in Puerto Rico. 相似文献3.
Myrtus communis L. (myrtle), a typical Mediterranean plant species belonging to the family Myrtaceae, was shown to form arbuscular mycorrhizal
symbioses in nature. Many different spore types were isolated from its rhizosphere and grown in pot cultures; six of them
were identified as Glomus species. In the laboratory, the myrtle root system was colonized by indigenous endophytes as well as by an Italian isolate
of Glomus intraradices. In greenhouse experiments, mycorrhizal inoculation reduced transplant stress in 60-day-old myrtle seedlings; their growth
was renewed immediately after transplanting, whereas non-mycorrhizal plants stopped development. Significantly larger growth
responses were obtained using indigenous fungi than the Italian isolate of Glomus intraradices.
Accepted: 16 January 1997 相似文献
4.
Steinkraus KH 《Biotechnology advances》1983,1(1):31-46
There has been a proliferation of books and papers dealing with the indigenous fermented foods/beverages of the world. It is anticipated that these foods/beverages will play an ever-increasingly important role in feeding both the developing and the developed world as population increases from approximately 4.5 billion to 6 billion by the year 2000 and to 8 to 12 billion people in the 21st century. The indigenous fermented foods consist of microbial protein grown on edible substrates. Microbial or single cell protein (SCP) per se continues to receive research and development attention. It is likely to play an important role in feeding animals in the future when it becomes competitive with soy protein. It may play a direct role in feeding humans in the future after its safety for feeding animals has been adequately demonstrated and it has been shown that it can be processed into foods acceptable to humans. At the present time, mushrooms, a form of microbial protein highly acceptable to humans, which can be grown readily on ligno-cellulosic and other agricultural and food processing wastes, offer considerable opportunity for expanding man's food supply. 相似文献
5.
Joydip Karmakar Rajib Roychowdhury Rup Kumar Kar Debal Deb Narottam Dey 《Physiology and Molecular Biology of Plants》2012,18(2):125-132
A total of ten rare indigenous rice landraces of West Bengal were screened for germination potential and seedling growth under varying concentrations of sodium chloride (NaCl) and polyethylene glycol (PEG) solutions as osmotic stress inducing agents. Among the studied rice landraces Kelas and Bhut Moori showed highest degree of tolerance to induced osmotic stresses. Proline content of the studied lines was also determined. Genetic relationship among the studied rice landraces was assessed with 22 previously reported osmotic stress tolerance linked Simple Sequence Repeat (SSR) markers. The identified allelic variants in form of amplified products size (molecular weight) for each SSR marker were documented to find out allele mining set for the linked markers of the studied genotypes in relation to osmotic stress tolerance. A Microsatellite Panel was constructed for the different allelic forms (size of amplified products) of each used marker. Among 22 SSR markers, ten showed unique alleles in form of single specific amplified product for the studied four genotypes which can be used for varietal identification. Genetic relationship among the studied rice lines was determined and a dendrogram was constructed to reveal their genetic inter-relationship. Polymorphism Information Content (PIC) for each used marker was also calculated for the studied rice lines. 相似文献
6.
Haider Karar Muhammad Amjad Bashir Reem Atalla Alajmi Dina M. Metwally Muneeba Haider Najeeba Haider Samad Raza Ali Bakhsh Rania Haddadi 《Saudi Journal of Biological Sciences》2021,28(7):3936-3942
In 2004–05, during the December to February about 141 mango farmers were interviewed during peak activity of mango mealy bug in southern Punjab, Pakistan. The objective was to know the farmers’ knowledge, perceptions and practices in the management of mango mealy bug. Most of the farmers (94.33%) reported that Chaunsa variety (king of all mango varieties) was susceptible to mango and irrigation water was the major source of flare up of this pest. Basudin and Supracide were the most commonly used insecticides as 72.92 and 51.77 percent farmers gave positive response and grease bands were applied for the control of mango mealy bug by the majority of the respondents. Hundred percent yield losses was told by 22.7 percent respondents whereas 75 percent, 50 percent and 25 percent losses were reported by 39.7, 31.9 and 14.2 insecticidal spray did not show satisfaction to the respondents for the control of fertilized females of mango mealy bug coming down from the trees. Lack of knowledge about the pest, lack of money, adulterated and shortage of pesticides, lack of unity amongst farmers Further the growers’ views were tested in the field for confirmation and small land holdings were the main constraints for the control of mango mealy bug. 相似文献
7.
Stèphan Kraai Lilly M Verhagen Enrique Valladares Joaquin Goecke Lorena Rasquin Paula Colmenares Berenice Del Nogal Peter WM Hermans Jacobus H de Waard 《Respiratory research》2013,14(1):76
Background
The International Study on Asthma and Allergies in Childhood (ISAAC) reported a prevalence of asthma symptoms in 17 centers in nine Latin American countries that was similar to prevalence rates reported in non-tropical countries. It has been proposed that the continuous exposure to infectious diseases in rural populations residing in tropical areas leads to a relatively low prevalence of asthma symptoms. As almost a quarter of Latin American people live in rural tropical areas, the encountered high prevalence of asthma symptoms is remarkable. Wood smoke exposure and environmental tobacco smoke have been identified as possible risk factors for having asthma symptoms.Methods
We performed a cross-sectional observational study from June 1, 2012 to September 30, 2012 in which we interviewed parents and guardians of Warao Amerindian children from Venezuela. Asthma symptoms were defined according to the ISAAC definition as self-reported wheezing in the last 12 months. The associations between wood smoke exposure and environmental tobacco smoke and the prevalence of asthma symptoms were calculated by means of univariate and multivariable logistic regression analyses.Results
We included 630 children between two and ten years of age. Asthma symptoms were recorded in 164 of these children (26%). The prevalence of asthma symptoms was associated with the cooking method. Children exposed to the smoke produced by cooking on open wood fires were at higher risk of having asthma symptoms compared to children exposed to cooking with gas (AOR 2.12, 95% CI 1.18 - 3.84). Four percent of the children lived in a household where more than ten cigarettes were smoked per day and they had a higher risk of having asthma symptoms compared to children who were not exposed to cigarette smoke (AOR 2.69, 95% CI 1.11 - 6.48).Conclusion
Our findings suggest that children living in rural settings in a household where wood is used for cooking or where more than ten cigarettes are smoked daily have a higher risk of having asthma symptoms. 相似文献8.
Guma Kunda Komey 《Ethnic and racial studies》2013,36(5):991-1008
The current situation of indigenous peoples in the Sudan is the result of the independent state's adoption of land and other policies identical to those introduced by colonialists more than a century ago. The Sudanese state has not only unwittingly maintained some colonial coercive institutions and policies but it has introduced more aggressive ones and brutally deployed them against its indigenous peoples, particularly the Nuba. In the light of this, this paper attempts to demonstrate analytically how some historical and contemporary socio-political dynamics have continued systematically to deprive these indigenous Nuba peoples of their customary land, and to assess to what extent the recently concluded Comprehensive Peace Agreement (CPA) has been successful in addressing the land question as one of the root causes of the recurring civil wars in the Sudan in general and in the Nuba Mountains in particular. 相似文献
9.
10.
The multiple use of distinct ecological environments in the search for wild resources has been practiced since ancestral times in aboriginal communities inhabiting northwestern Patagonia. This paper examines the actual use and knowledge of wild edible plants in a Mapuche community presently settled in one of the most arid areas of Patagonia, far from the temperate forests where their ancestors used to live. The difference between knowledge of and use of wild plants is analyzed emphasizing that these differences could contribute to the understanding of eroding processes believed to be occurring in the community. These objectives are studied quantitatively by utilizing ethnobotanical indices, partially derived from ecological theory. Our results indicate that the Paineo dwellers still utilize multiple ecological gathering environments and have thorough plant knowledge of both native and exotic species. The Andean forest, more than 50km away from this community, is the environment from which the Paineo dwellers know the greatest total richness and the highest diversity of wild edible plants, followed by the Monte–Steppe species and lastly, those growing around their homes. The transmission of wild edible plant knowledge in the Paineo community diminishes with age, and the forest plants are the most vulnerable to loss. Our results have shown that the knowledge and consumption of wild edible plants follows a pattern according to ecological conditions of the gathering environments, as well as the cultural heritage of the Paineo people. 相似文献