Ilmu Pengetahuan Lingkungan

Kerjakan Tugas terjemahan (mk IPL) ini dan ditumpuk hari Kamis 26 Februari 09

Global Issues.

In temporal context human community began to exert a major influence on global environments with the onset of permanen agriculture 10 000 years ago. Although this was not the "revolution" that it has often been called,as it grew out ofsophisticated hunter-gatherer strategies,it created environmental and cultural changes of an unprecedented nature. It developed in tandem with permanent settlement, facilitated the division of labour and marked the emergence of society as a significant force on the landscape. The onset of permanent agriculture also marked the first stage of global deforestation, a process that began in localized areas but which is now a global problem. Deforetstation together with fosisil fuel energy production are among the most important issues of the 1990s, not least because of their efffect on global climate via their impact on the biogeochemical cycle of carbon. Global warming could influence all aspects of of environmental and cultural processes, although it remains controversial because, as yet, there is no definitive evidence that it is becoming reality. Deforetstation is also linked with spesies extinction and declining gene pools; both represent the deminution of resources, the potential of which has not been fully realized. What is perhaps most disconcerting about the current deforestation of tropical forest is the fact that many of the agricultural systems replacing them are also failing. For example, large-scale ranching ranching in Central and South America has, in general, not provided the salvation to national economies that it initially promised.

Population growth and demographic trends are also global issues. Burgeoning population in the developing world and changing demographic patterns in the developed world, are both a matter for concern. Increasing populations inevitably mean greater pressure on resources, but the relationship with environmental damage is complex. Individuals in the developing world exert different pressures on resources than do those in the developed world, where income, age and family structures will influence environmental impacts in the 1990s. At the sama time there are scientific and technologycal developments that may offset some of the problems that affect humanity. Biotechnology and genetic engineering provide new opportunities for agriculture which, in principle, could lead to the tailoring of crops to the environment rather than vice versa, which has been the traditional approach. Biotechnology is providing new ways to treat watste, including the recycleing of useful materials. In the longer term such developments should contribute to sustainable resource use.