As one of the regions with the richest rainfall in the world, why does Taiwan Province Province have such a serious water shortage crisis?

Experts and scholars in Taiwan Province Province have recently reminded people that in recent years, the rainfall in Taiwan Province Province is getting less and less, especially in the northern part of Taiwan Province Province.

Taiwan Province Province is located in the subtropical zone, with unique natural conditions and abundant rainfall, which is three times the global average. However, due to the dense population, the per capita rainfall is less than the global average 1/6. 80% of the rainfall in Taiwan Province Province is concentrated from May to 10, and the dry season lasts for six months. In addition, the rivers in Taiwan Province Province are short and steep, with poor water storage capacity, which requires water storage regulation.

There are about 40 reservoirs in Taiwan Province Province with a total storage capacity of 2 billion tons. The total annual water consumption in Taiwan Province Province is 654.38+08 billion tons. In addition to introducing 8 billion tons from rivers and extracting 6 billion tons from groundwater, the remaining 4 billion tons need to be replenished by reservoirs. Therefore, most reservoirs need to be reused twice a year, and some need to be reused three times. Therefore, whenever there is drought in spring or winter, the water storage capacity of Emerald Reservoir and Shimen Reservoir in northern Taiwan Province Province will decrease, and the northern Taiwan Province Province will be short of water.

The serious water shortage in northern Taiwan Province Province has attracted the attention of experts and scholars. According to the data of meteorological department of Taiwan Province Province, the rainfall in Keelung in the north of Taiwan Province Province has increased in the past century, but the number of rainy days has decreased. Further analysis shows that there is less light rain and more moderate and heavy rain. The drizzle in the past turned into a shower that came and went in a hurry, and the water left on the ground was obviously not as good as before. Scientists have analyzed that the reason may be the influence of suspended particles in air pollutants on clouds. This effect increased the cloud cover on the island, and the sunshine time in Taiwan Province Province decreased by about 15% in recent 30 years.

The above reasons are not the main reasons for water shortage in Taiwan Province Province. The reason for the real water shortage on the island is that the water consumption is too large and the water resources are insufficient. In the past 50 years, the water consumption in Taiwan Province Province has almost doubled. Groundwater exploitation has exceeded 50% of natural recharge, resulting in ground subsidence and seawater intrusion. In addition, people compete with mountains for land, and forests that can protect water and soil are replaced by cash crops that are not conducive to protecting water and soil, such as betel nuts, tea gardens and orchards. It not only loses the function of forest to conserve water and soil, but also accelerates soil erosion and even leads to serious natural disasters such as mudslides. As for the reservoir, at present 1/3 has good nutrition, which seriously affects the water storage capacity. When rainfall is concentrated and sudden, soil and water conservation is also facing a severe test. Due to the poor soil and water conservation in many catchment areas, a large amount of sediment will flow into the reservoirs during the rainstorm, and the sedimentation rate of many reservoirs exceeds 40%. Experts warn that these reservoirs will lose their water supply function within a few years if they are not rectified.