Plant population

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  • This book is about the conservation of genetic diversity of wild plants in situ in their natural surroundings, primarily in existing protected areas but also outside conventional protected areas. A lot of effort has been dedicated to conserving plant biodiversity, but most of this has focused on rare plant communities or individual species threatened with extinction.

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  • Bacteria that associate with plants are diverse in their ability to affect plant health, their genotypic and phenotypic characteristics, and their phylogeny. These bacteria are typically members of complex microbial communities, with only a few establishing pure clonal populations within a plant.

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  • Tham khảo sách 'aquarium plants: their identification, cultivation and ecology', khoa học tự nhiên, công nghệ sinh học phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả

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  • Plant species that invade an alien area and outgrow the native vegetation, establishing and increasing their own territory, often lead to negative economic, environmental, and social impacts. Even native species can behave like invasive species by their exponential spread. Similarly, not all non-native species are invasive. Many alien invasive species, however, do threaten the health and integrity of our terrestrial and aquatic ecosystems.

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  • Research show that RVT doesn’t has any side effect on fertility. In 200 cases of pregnancy after RVT 66% lead to neonate birth. Premature birth before 37th week happened in 27% of the cases. Abortion rate in first trimester was 16-20% like general population and second trimester abortion was 9.5% (Plante et al., 2005; Jolley et al., 2007). If the tumor volume is less than 500mm, tumor size is less than 2 cm and invasion depth of stroma is less than 2mm we can do ultraconservative operations include simple trachelectomy or extensive conization with knife. In this...

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  • The past two hundred years have witnessed two exploding trends: rapid population growth following the decline in mortality due to both the medical revolution and the improvement in living conditions and a steep increase of resource depletion and environmental degradation following the industrial and agricultural revolutions. Both of these trends have accelerated over the past 50 years, fueling the debate on the linkages between population and environment that began 150 years earlier with Malthus’ concern about the capacity of fixed land to feed an exponentially growing population....

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  • In dense plant populations, individuals shade each other resulting in a low-light habitat that is enriched in far-red light. This light quality gradient decreases the efficiency of the photosynthetic light reaction as a result of imbalanced excitation of the two photosystems. Plants counteract such con-ditions by performing acclimation reactions.

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  • Contraceptive use accounts for a substantial portion of the variation in observed fertility rates (others include age of marriage, abortion rates, post- partum amenorrhea and abstinence, and occurrence of marital separations). Although there have been dramatic increases in the use of family planning services, unmet need for family planning remains very high in low-prevalence regions.

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  • Economic development, population growth, and environmental pollution evolving in many parts of the world are placing great demands on existing resources of fresh water and reflecting a "water crisis". Resource management, efficient utilization of the water resources, and above all water purification are all alternatives to resolve the water crisis. Purification approaches include traditional approaches that have lasted for several centuries without major modifications as well as new innovative approaches....

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  • Does this mean that differences in genetic diversity levels will have predictable ecological consequences? The answer is no, because only one portion of genetic diversity is connected to ecological factors, i.e. adaptation. Ecological adaptation is a significant factor for example, in range expansion of plant species. Plants with different genotypes conferring the highest levels of fitness are expected to survive and reproduce better, shifting the gene pool over time towards higher frequencies of the alleles making up the more successful genotypes (Ward et al., 2008).

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  • The theoretical metrics developed, such as genetic variance and heritability (Fisher, 1930; Wright, 1931), provided the quantitative standards necessary for the evolutionary synthesis. Further research has focused on the origin of genetic diversity, its maintenance and its role in evolution. Simple questions such as “who breeds with whom” initiated studies on the relatedness of populations.

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  • Since the 1930s, the USDA (U.S. Department of Agriculture) Forest Service’s International Institute of Tropical Forestry (the Institute) has studied mahogany and its management. In the 1960s, F.B. Lamb, the author of the classic book on mahogany (1966), was an Institute collaborator. Before gene flow and genetic erosion became popular terms, my predecessor Frank Wadsworth established a gene bank at the Luquillo Experimental Forest.

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  • In essays with settings that range from the Wind River Mountains of Wyoming, to the mountain town of Leadville, Colorado, to the Pine Barrens of New Jersey, Trudy Dittmar weaves personal experience with diverse threads of subject matter to create unexpected connections between human nature and nature at large. Life stories, elegantly combined with mindful observations of animals, plants, landscape and the skies, theories in natural science, environmental considerations, and touches of art criticism and popular culture, offer insights into the linked analogies of nature and soul....

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  • The serious challenge facing the world today, in obtaining enough energy for growing population and in controlling the carbon emission caused by fossil fuel use, calls for nuclear energy as an alternative power source. This book presents research work and technical experience from several power plants and research institutions around the world from practical prospective.

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  • How different levels of genetic variance affect the rate of evolutionary change within populations has also been intensively studied. Such changes were originally studied using phenotypic markers: variation among individual plants in traits, such as leaf shape or flower color (Ward et al., 2008). Subsequently the detection of genetic variation has become more sensitive, firstly through the utilization of variation in enzymes (allozymes) and then through PCR-based marker systems allowing direct examination of DNA sequence variation.

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  • With the vast and ever increasing demands made upon materials which are the products of cultivated fields, for food, for apparel, for furnishings and for cordage, better soil management must grow more important as populations multiply.

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  • Numerous U.S. REITs and other institutions have invested in real property connected to maquiladoras, retail development and tourism. This trend should persist because Mexico is ripe for continued investment. With respect to retail development, for example, there are fewer than 1,000 malls and shopping centers in Mexico, which has a population of approximately 110 million people. In comparison, there are more than 102,000 malls and shopping centers in the U.S., which has a population of approximately 306 million people.

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  • This book, now in its third edition, began almost 25 years ago when Weed Ecology: Implications for Vegetation Management was published in 1984. That text concentrated on the need for farmers, foresters, rangeland managers, and the researchers who advised them to understand better the biology of weeds and the role people play in creating and maintaining weeds in agriculture and other production systems. We were assisted in that first effort by the writings of many early scientists, such as J. L. Harper, H. G. Baker, and E. J.

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  • This short book is about conserving insects, the most diverse and abundant animals that share our world. In particular, it is about the common focus of conserving individual species of insects. This so-called ‘fine filter’ (or ‘fine grain’) level of conservation parallels much conservation effort for better-understood groups of animals such as mammals and birds, for which species-focused conservation exercises are commonplace.

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  • Many of the techniques that have been developed have already been used to study the extent and distribution of variation in species gene-pools and to investigate evolutionary and taxonomic relationships among plant populations. With the development of the polymerase chain reaction (PCR) based techniques, in particular, numerous molecular technologies have been, and still are being, developed, which can be used for the detection, characterization, and evaluation of genetic diversity in plant populations.

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