ray ban occhiali Explore the natural phenomena beh

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Explore the natural phenomena behind human activities - for example Environmental History of China
Abstract: behind the natural phenomena of human activities. Yellow River and Yellow River flooding and soil erosion production and lifestyle of residents are closely related. Huangtugaoyuan ancient forest growth, there was a good ecological environment,ray ban occhiali, Zhou and Qin cultivated over time and cause of the current Debiao tributaries cut broken ravines horizon is difficult to control the landscape. Desertification is a social phenomenon of this natural phenomenon is the result of human activities on natural. Human destruction of forests caused by reduced rainfall is an important reason. Environmental history should be based on the perspective look at man and nature, to explore natural phenomena behind human activity.

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Key words: China's environmental history; ecological environment; human activities; interaction

Human beings are a product of nature, the Earth developed to a certain stage of the product. Therefore, the dependence of human nature particularly evident in the daily life of human beings rely on the natural gift of all, the geographical environment on human development had a tremendous impact. Hunting peoples, nomadic, agriculture ethnic distinction, largely determined by geography. Once popular in Western countries, environmental determinism, reflects a relationship between human beings and an understanding of nature.
Into the 20th century, because of scientific and technological progress, human exposure to the nature of the rapid expansion of the scope and depth, and thus open up people's horizons, and many people to explore the natural relationship between humans and the other side, that human activities on natural What is the impact that China scholars in the study of natural disasters in the process, discovered the natural phenomenon behind human activity. These findings are very important, it is warning people to be kind to nature, to avoid the occurrence of certain natural disasters.

One
Yellow River Yellow River Flood and Water Conservation is the principal source of the Chinese nation, but it is the Chinese Yellow River Flood brought grave disaster. Cause flooding on the Yellow River, had previously been considered to be the result of natural processes, caused by the rainstorm. 60 years of the 20th century, some scholars found in the study of the Yellow River flooding, less flooding during the Qin Dynasty, Han Dynasty particularly severe flooding from Xinmang to the Sui Dynasty in 500 years, flooding significantly reduced the emergence of long-term safety and flow of the situation. To flooding and increased the Tang Dynasty.
Of the Yellow River flooding in different historical periods Why this difference? After further research found that different ethnic groups and the Yellow River middle reaches of the production of lifestyle.
Yellow River is a special focus on heavy rain, soil erosion is very serious, and flood sediment in the Yellow River comes mainly from the Yellow River region. In the Qin Dynasty, the Yellow River is the Rong and Di ghettos, the Rong and Di are hunting, livestock nation do not understand farming. For this reason, the vegetation is not destroyed, still maintain their initial state. Good forest cover to prevent soil erosion. Thereby reducing the sediment into the river and flooding.
To the Qin and Han dynasties, rulers expelled the minority here, for frontiers of political considerations, a large number of immigrants to the Yellow River region, the establishment of county , the reclamation of wasteland, the original forest vegetation unprecedented destruction, the result caused serious soil erosion, so that the river sediment, increased flooding, resulting in increased downstream river bed, flood flooded. Western Han Dynasty, the Yellow River flooding is particularly serious, that is, the resulting.
To Xinmang after the separation of the three countries through the Central Plains and the Northern and Southern Han regime in decline, the Huns, and many other minorities have seized the opportunity Wuhuan south, occupied the middle Yellow River region. County during the Qin and Han abandoned, deserted by all the cultivated land, a minority of the ranch. So. So that the original forest cover was destroyed to recovery and development, soil erosion greatly reduced. So the Yellow River flow security situation there.
Yellow River flooding is a natural phenomenon, the presence or absence of the Yellow River flooding, soil erosion is closely related with the severity of the Yellow River in the production of life is related to the direct cause of soil erosion. In other words, people's production and life of the Yellow River flooding.

Second, the growth over the Loess Plateau is located in the Qinling forest
north of the Loess Plateau, the Great Wall to the south west of the Taihang Mountains, Wushaoling east area about 40 million square kilometers. Forest rare, strong erosion,Ray-Ban RB3428, soil erosion, mainly from the Loess Plateau, Yellow River sediment. Land Resource poor, densely populated areas is lagging behind economic and cultural development. Consideration from the land improvement, tree planting here need to strengthen the soil and water conservation. However, if the growth over the ancient forest on the Loess Plateau? This became an important issue in decision-making. Many earth scientists believe that the growth of the Loess Plateau has never been forest, afforestation is not feasible.
To some scientists is based on the remarks, first, on Forest and the rare, bare ########## everywhere, the second is not found in the loess tree pollen , the study of ancient pollen is the most reliable basis for plant species.
Historian According to literature, that the growth of the Qin Dynasty is the Loess Plateau forest, in the Lin, Hirabayashi, in the forest and so on. Long Hill in the west of the Weihe River, popular to replace the clay tile shingles,
China's ancient civilization, the earliest emergence of Loess Plateau, it reflects from one side of the Loess Plateau has a good ecological environment for human life. Plateau is the Zhou, Qin birthplace of the Zhou Dynasty, Qin people are part of an agricultural nation, they reclaimed land, to create a palace and the tombs of the process, huge deforestation, the trees were cut down almost completely, the result is caused soil erosion, resulting in broken surface tributaries, ravines aspect of the landscape, difficult to remediation. The pollen is otherwise scarce
reason. Soil erosion in the formation of a large number of pollen lost to the sea, in addition, microorganisms in loess and calcium carbonate, fossil pollen levels will reduce, or even total loss. For these reasons, in the Loess Plateau can not judge whether the pollen of trees without the forest of ancient trees. Since ancient times there have been
Plateau forests exist. Proved here that for the growth of forests, afforestation can be used to prevent soil erosion. As also with other regions of Loess Plateau, soil and water conservation afforestation as the basic way for the government decision-making important scientific basis.

Third, the duality of the proposed
desertification Desertification and desert are two closely related scientific terms. Means the accumulation of large areas of desert sand, the desert is characterized by loose, liquid, in the pre-Qin classics are called quicksand. Also known as desertification or sandy desertification desertification, the desert is the place where the past does not appear similar in terms of the desert landscape. The process of desertification, there are two, one under the action of the desert in the expanding wind, the leeward area of ？？arable land burial, and second, the upper surface is damaged, causing a G V
exposed sand, surrounded by diffusion, the formation of the desert landscape.
Desertification occurs early, is an international problem. Palmyra Western Asia, Bite La. China Loulan, absolutely fine (now known as Virginia), Juyan, as well as India, Pakistan, in some areas, has long been mired in ancient desert oasis, became part of the desert. However, research on desertification has started very late. Until the late 20th century, only 40 people turned to the study of desertification.
Desertification occurred mainly in the arid and semi-arid areas, therefore, many scientists believe that purely natural phenomenon of desertification is the inevitable result of dry climate, not human to avoid, so do not throw money in the fight against desertification areas. Click here to pessimism, human inaction in the face of disaster, desertification can only be placed.
Chinese scholars on desertification issues in-depth research and found that the arid climate, sandy environment, desertification is a prerequisite for and material basis, the real cause of desertification is human activities. Han's absolutely fine in the destruction of water resources in agricultural farming, leading to desertification in the oasis; Loulan is due to the decline of the Tarim diversion; Han Juyan is due to the disruption of surface soil cultivation caused by desertification. 50 years after the beginning of the 20th century, the Tarim River to cut down large areas of cultivated species of Populus, the result of serious desertification, the new farming land reclaimed sand buried shortly thereafter.
A lot of facts show that desertification is both a natural phenomenon, but also a social phenomenon, is the natural result of human activities, this is the duality of desertification. Correct understanding of the duality of desertification,MAC Cosmetics UK, desertification prevention and control measures in science to develop the basic premise and starting point. Desertification duality assertion made, domestic and foreign academic endorsement and recognition.

IV effects on the rainfall of the forest there are many
forest ecological functions, in addition to function of rainfall, but did not arouse enough attention.
The input of marine water vapor is the basic cause of land precipitation. Distances by sea and from the obstacles of terrain, land rainfall is uneven. Meteorologists drawn the rain chart,ralph lauren outlet, a clear indication of the heterogeneity of rainfall and rainfall, according to the number of the land is divided into sub areas, sub-humid areas,nike dunks, semi-arid, arid area.
To the same area concerned. Rainfall also showed heterogeneity. Minyan will call this: The Hills does not rain, the river does not rain, across the road does not rain. Here is the heavy rain, there are few raindrops, and even a sunny day. The reasons for this phenomenon? Has found that the forest vegetation and surface