Kuliah Pengelolaan Air untuk Pertumbuhan Tanaman Siklus Hidrologi

Siklus Hidrologi Output perkuliahan : Dapat menggambarkan siklus hidrologi secara umum dan kaitannya bagi pertumbuhan tanaman Dapat memahami proses perpindahan air di permukaan tanah Dapat memahami keseimbangan yang terjadi pada siklus hidrologi

Siklus Hidrologi Siklus Hidrologi menggambarkan distribusi and pergerakan air di permukaan bumi dan atmosfer water Siklus hidrologi meliputi pergerakan air kontinyu antara permukaan tanah, sungai, laut, tanaman, tanah dan atmosfer.

Siklus Hidrologi

Evaporasi Energi panas dari matahari menyebabkan terjadinya penguapan air dari permukaan bumi (berasal dari tanah, sungai, danau, lautan)

Transpirasi dari tanaman Transpirasi dari tanaman. Transpirasi adalah penguapan air dari permukaan tanaman. Evapotranspirasi – kehilangan air akibat penguapan dari permukaan bumi dan tanaman

Kondensasi Proses perubahan uap air yang terjadi akibat evapotranspirasi menjadi bentuk awan yang dapat menimbulkan hujan.

Adveksi Proses pergerakan awan yang dapat menimbulkan hujan

Presipitasi / Hujan Precipitasi adalah hujan (proses turunnya air dari awan ke permukaan bumi), dan pada dareah beriklim subtropis, dapat berbentuk salju

aliran air di dahan (panah merah) – air mengalir melalui dahan dan ranting tanaman Aliran air jatuhan hujan (panah kuning) air hujan jatuh tertahan oleh daun dan menetes ke permukaan tanah

Run off / Limpasan Permukaan Air yang mengalir di permukaan tanah, dan tidak dapat diserap oleh pori-pori tanah  mengarah ke sungai, laut atau danau

Aliran air bawah tanah Air yang mengalami infiltrasi (masuk ke dalam pori tanah) dan turun ke bawah melalui lapisan batuan dan mengalir di bawah permukaan tanah menuju danau, sungai atau laut

Aliran air bawah tanah

The water cycle balance Usually the water cycle is in balance, and the amount of precipitation falling will slowly soak into the ground and eventually reach the rivers. However, if rain falls for a long period of time or if the ground is already soaked or saturated with water then the chance of flooding is increased.

Under the ground

Siklus tertutup The hydrological cycle is a good example of a closed system: the total amount of water is the same, with virtually no water added to or lost from the cycle. Water just moves from one storage type to another. Water evaporating from the oceans is balanced by water being returned through precipitation and surface run off.

Human Inputs to the Cycle Although this is a closed system there is a natural balance maintained between the exchange of water within the system Human activities have the potential to lead to changes in this balance which will have knock on impacts. For example as the earth warms due to global warming the rate of exchange in the cycle (between land and sea and atmosphere) is expected to increase.

Human Inputs Some aspects of the hydrologic cycle can be utilized by humans for a direct economic benefit Example: generation of electricity (hydroelectric power stations and reservoirs) These are effectively huge artificial lakes and this will disrupt river hydrology (amount of water in a river)

Other Human Activities Paving, compacting soils, and altering the nature of the vegetation (including deforestation) The mining of ground water for use in agriculture and industry Large amounts of water vapour released into the atmosphere from industrial activity Large changes in vegetation by wildfire, logging, clearance for agriculture

TUGAS Jelaskan hal di bawah ini: Infiltasi Aliran air bawah tanah Limpasan permukaan Siklus tertutup Evapotranspirasi