차례:
산림수문학(지표수, 수문곡선) 13-02 (할 수있다 2024)
대수층 에서 물을 함유하고이를 상당한 양으로 방출하는 암석층. 암석은 물로 채워진 기공 공간을 포함하며, 공간이 연결되면 물은 암석의 매트릭스를 통해 흐를 수 있습니다. 대수층은 또한 내수성 지층, 렌즈 또는 구역으로 불릴 수도 있습니다. 우물은 많은 대수층으로 뚫을 수 있으며 지구상에서 가장 중요한 담수 공급원 중 하나입니다.
터널 및 지하 발굴: 수자원 관리
수면 아래의 부드러운지면 터널에는 토양으로 유입되는 토양과 물이 끊임없이 유입 될 위험이 있습니다.
종류
한정된 대수층은 물을 감지 할 수 없거나 불 투과성 인 암석층에 의해 한정되거나 덮어지는 수성 지층입니다. 시험에 따르면 한정된 층 또는 층이 물을 쉽게 전달하지는 않지만 시간이 지남에 따라 느린 누수로 인해 많은 양의 물이 기여하여 주요 대수층에서 생산을 보충하는 것으로 나타났기 때문에 실제로 한정된 대수층은 거의 없을 것입니다.
A groundwater aquifer is said to be unconfined when its upper surface (water table) is open to the atmosphere through permeable material. As opposed to a confined aquifer, the water table in an unconfined aquifer system has no overlying impervious rock layer to separate it from the atmosphere.
Recharge
The water found in aquifers is replenished by drainage through the soil, which is often a slow process. This drainage is referred to as groundwater recharge. Rates of groundwater recharge are greatest when rainfall inputs to the soil exceed evapotranspiration losses. When the water table is deep underground, the water of the aquifer may be exceedingly old, possibly a result of a past climatic regime. A good example is the water of the Nubian Sandstone Aquifer System, which extends through several countries in an area that is now the Sahara. The water is being used extensively for water supply and irrigation purposes. Radioisotope dating techniques have shown that this water is many thousands of years old. Similarly, the massive Ogallala Aquifer of the Great Plains in the United States no longer receives the water recharge from the Rocky Mountains that formed it during the Pliocene Epoch (5.3 million to 2.6 million years ago). The use of such water, which is not being recharged under the current climatic regime, is known as groundwater mining.
In many aquifers, groundwater levels have fallen drastically in recent times. This is commonly due to the diversion of aboveground water sources as well as to excessive groundwater mining for irrigation and other uses. Such depletion increases pumping costs, causes wells and rivers to dry up, and, where a coastal aquifer is in hydraulic contact with seawater, can cause the intrusion of saline water. Attempts have been made to augment recharge by the use of wastewaters and the ponding of excess river flows.
