SOIL DEGRADATION AND GARBAGE ISSUE
The earth’s natural cover consists of a complex and dynamic ecosystem of minerals, air, water, and organic materials that collectively sustain all of life. It is among our most precious resources, yet roughly half of the world’s soil has been lost over the past 150 years, most of it the result of human actions.Soil degradation is the loss of nutrients or organic matter or, alternatively, pollution by toxins so that the soil loses its quality and productivity and can no longer be used for growing.The main cause of soil degradation is erosion, whether by weather, wind, water, or gravity, naturally and gradually wearing away the earth’s surface. Human intervention has greatly accelerated the loss so fertile soil is removed faster than it can be replenished. For example, the pressures of the growing population have led farmers to use harmful pesticides and fertilizers to increase crop yield.
In urban areas, industrial pollutants and household garbage, especially non-biodegradable products like plastics and electronic waste, have reached a crisis stage compared by the World Bank to the severity of climate change; they also contribute to it, as landfills emit more and more methane gas into the air every day. Accurate global data is difficult to compile, as practices in different countries and regions vary widely, but since the amount of solid waste increases with economic development and urbanization, the environmental and human health risks will undoubtedly grow. Municipal solid waste is expected to double by 2025.
Improved classification system integrated with city planning and building system seems to be critical to better collect and classify waste in order to make use of valuable waste to recycle and compost. Human waste (night soil) can be turned into fertilizer, in the process will produce methane as a bi-product. On-site composting program can collect and compost food wastes from restaurants and dining room table into farm use in the peripheral agricultural areas.
地球表面由各种矿物，空气，水，以及有机成分复合而成，并形成了一个由多种生物组成的动力生态系统。我们曾经拥有许多珍贵的土地资源，然而，由于频繁而复杂的人类活动，将近一半的土壤都在过去的150年中流失了。土壤退化归根到底是营养物质以及有机体的流失。又或者说，这些流失是由于土壤污染所造成的土地质量及生产力下降造成的 -- 贫瘠的土壤无法培育植被和作物。土壤退化的主要原因之一是土壤侵蚀。造成土壤侵蚀的原因有很多，包括气候，风力，水力，或重力。这些自然因素慢慢地将土壤以各种形式“带走”。人类活动的介入极大力加速了肥沃土壤的流失，甚至超过了土壤自我循环补充的周期。例如，巨大的人口增长压力迫使农民使用对作物有害的杀虫剂及人工肥料来增产。这是十分危险的。