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Growing Human Population (growing + human_population)
Selected AbstractsSNOWSHED CONTRIBUTIONS TO THE NOOKSACK RIVER WATERSHED, NORTH CASCADES RANGE, WASHINGTON,GEOGRAPHICAL REVIEW, Issue 2 2002ANDREW BACH ABSTRACT. Meltwater contributes to watershed hydrology by increasing summer discharge, delaying the peak spring runoff, and decreasing variability in runoff. High-elevation snowshed meltwater, including glacier-derived input, provides an estimated 26.9 percent of summer streamflow (ranging annually from 16 to 40 percent) in the Nooksack River Basin above the town of Deming, Washington, in the North Cascades Range. The Nooksack is a major spawning river for salmon and once was important for commercial, recreational, and tribal fishing, and in the past its flow met the demands of both human and aquatic ecosystems. But the river is already legally overallocated, and demand is rising in response to the rapidly growing human population. Variability in snowshed contributions to the watershed is considerable but has increased from an average of 25.2 percent in the 1940s to an average of 30.8 percent in the 1990s. Overall stream discharge shows no significant increase, suggesting that the glaciers are melting, and/or precipitation levels (or other hydrologic factors) are decreasing at about the same rate. If glaciers continue to recede, they may disappear permanently from the Cascades. If that occurs, their summer contribution to surface-water supplies will cease, and water-management policies will need drastic revision. [source] Twenty years of rest returns grazing potential, but not palatable plant diversity, to Karoo rangeland, South AfricaJOURNAL OF APPLIED ECOLOGY, Issue 4 2010Colleen L. Seymour Summary 1.,Up to 73% of the world's rangelands are degraded, and increasing demand for meat in developing countries and a growing human population are likely to exert even greater pressures on rangelands in the next 20,50 years. Restoration of rangeland grazing potential and resilience is therefore important, particularly in the face of climate change. 2.,We investigated the influence of past stocking rates (from 1910 to 1987), rainfall, and current grazing regimes (from 1988 to 2008) on plant assemblages, grazing potential, and diversity of palatable species in southern Karoo rangelands, South Africa. 3.,We used herbivore exclusion experiments to test whether resting rangeland for 20 years enables recovery of plant assemblages (where seed sources are present within 50 m), regardless of previous grazing history. Mean annual rainfall over this period was 15% higher than the mean annual rainfall for the preceding 80 years and included two exceptionally wet years. 4.,While rainfall was a primary driver of total vegetation cover, grazing history explained differences in plant species composition: plots with shared historical grazing intensity were more similar than plots with the same grazing regimes between 1988 and 2008. 5.,In historically heavily-grazed exclusion plots, cover of the palatable species Tripteris sinuata (formerly Osteospermum sinuatum) returned to levels comparable to that in both exclusion and lightly-grazed plots with a moderate grazing history. Five palatable species (Pteronia empetrifolia, Tetragonia spicata, Berkheya spinosa, Hereroa latipetala and Ruschia spinosa) failed to re-establish, however, despite the presence of seed-producing plants nearby. Furthermore, only cover of P. empetrifolia increased significantly in historically moderately-grazed plots. Cover of unpalatable plants (e.g. Pteronia pallens) increased in all plots over time. 6.Synthesis and applications. These findings suggest that present species composition of arid shrublands reflects historical management at time scales greater than 20 years. Despite high rainfall enabling the return of grazing potential through recovery of a single forage species, rest alone did not ensure the return of all palatable species, with implications for rangeland resilience. Restoring the full suite of palatable species over management timeframes will require more complex interventions such as reseeding or selective clearing. [source] Genetically Engineered Crops: Their Potential Use for Improvement of Human NutritionNUTRITION REVIEWS, Issue 5 2002Lin Yan Ph.D. Great success has been achieved in increasing agriculture productivity to fulfill human needs during the second half of the 20th century. However, there will be much greater challenges in the future. Based on the current population growth rate of 1.4% per year, the world's population is forecast to increase from the current level of approximately six billion to nine to twelve billion in 50 years. In addition to continuously increasing demand for agricultural production, there is an urgent need to improve the nutritional quality of human diets for this rapidly growing human population. Malnutrition is still a worldwide health issue. Macronutrient and micronutrient deficiencies are prevalent in developing countries, and over-consumption of certain nutrients in developed countries (e.g., saturated fatty acids) is associated with high incidence of certain chronic diseases. Furthermore, there will be declining natural resources such as arable land and water, and the challenges to humans must be met without further degrading the environment. Biotechnology offers a valuable tool to help achieve these goals. This review focuses on the most recent advances in biotechnology, which promise to improve human nutrition by enhancing the nutrient density of plant foods. Issues relating to the safety of food products from genetically engineered crops are also discussed. [source] Potential of Pakistani camel for dairy and other usesANIMAL SCIENCE JOURNAL, Issue 5 2007Muhammad YAQOOB ABSTRACT Camels have the potential for milk, meat and draught power and can contribute a handsome share of the production of these commodities. The potential of this wonderful animal has never been realized and it could be harnessed as a prospective milk producing animal. The future of animals that can thrive under harsh environmental conditions, the camel being at the top of the list, is bright. The camel is still a neglected species in Pakistan and has not received the proper attention of researchers and scientists. The population explosion, urbanization and industrialization have expanded agricultural activities to produce more food for the rapid growing human population of the country. Cultivated areas are shrinking, thus reducing the fodder production area for buffalo and cattle. Under these circumstances we have to search for other available sources to enhance milk production. The environmental changes occurring on the earth and the water shortage in the region have also adversely affected the production potential of buffalo, cattle, goats and sheep. Under these changing ecological circumstances, rearing camel is the best option for more milk production and the proper utilization of the vast unused lands of this country. Most studies also have named the camel as an animal of great socioeconomic importance in large tracts of the industrializing world. The camel serves as a cheaper source of power for drawing water from wells, plowing and leveling land, working mini extraction mills (extracting from oil seeds), grinding wheat, corn and other grains and crushing sugarcane and pulling carts for the transportation of goods as well as people. [source] | ||||||||||