Deuterium-excess determination of evaporation to inflow ratios of an alpine lake: Implications for water balance and modeling

The existence of water as a crop growth requirement is a prerequisite in tropical drylands. In addition, water balance, as an important part of climate change, is needed to be accessed under certain conditions. This study aimed to observe water availability and analyze water balance at drylands for farming planning purposes. The results of this study were then required to determine planting patterns and farming planning in the tropics, in which information related to hydrology is still lack. The Thornthwaite-Mather method approach was used in this study to analyze water balance in areas observed and. Because of its simplicity, this method can also be applied to areas with limited data. The water balance analysis that provides the information on water availability can be used as basic consideration for farming planning, especially at drylands in which water availability is a critical factor for farming activities. In tropical drylands, the cropping pattern of food crops – secondary crops – fallow – horticulture crops can be proposed within farming planning. Maize as a food crop can be planted for the early planting period in January, in which it can be harvested at the age of 80 days around March. In the following month, secondary crops such as soybeans can be planted and harvested at 135 days. Fallow periods during August and September, the lands cannot be optimally used because of water deficit. Entering the beginning of October, the land can be cultivated and prepared for the next crop, eggplant, as horticultural crops, harvested at 135 days in early February.

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Determination of constituents receipt Kakhovka Reservoir water balance

Ukrainian hydrometeorological journal ◽

10.31481/uhmj.16.2015.28 ◽

2017 ◽

pp. 209-214

Author(s):

O.S. Koryagina

Keyword(s):

Surface Water ◽

Water Resources ◽

Water Balance ◽

Practical Importance ◽

Surface Flow ◽

Probable Error ◽

Scientific Interest ◽

Reservoir Water ◽

Surface Water Flow

The study of the reservoirs is of great scientific interest and is of practical importance for the solution of problems of rational use and protection of water resources. The paper describes the latest reservoir in the cascade of Dnipro Kakhovka Reservoir and its component of water balance. The methods of determining the components of the water balance that were once offered the Kakhovka hydrometeorological observatory are submitted. Great attention is drawn to the surface flow of water into the reservoir from unexplored rivers, which is determined by the method of analogy. The probable error of this method, in turn, is equal to for monthly values 30-50% and annual – 10-20%. So, there is provided somewhat different a method for determining the surface flow using the curve of security component amount of annual precipitation, maps of the norm runoff and tables SNiP 2.01.14.83. The proposed method simplifies and accelerates the process of calculating the amounts of surface water flow in unexplored rivers to Kakhovka reservoir.

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Penentuan Musim Tanam Berdasarkan Perhitungan Neraca Air Lahan di Daerah Saumlaki, Pulau Yamdena

JURNAL BUDIDAYA PERTANIAN ◽

10.30598/jbdp.2020.16.2.173 ◽

2020 ◽

Vol 16 (2) ◽

pp. 173-179

Author(s):

Jenly F Uspessy ◽

Samuel Laimeheriwa ◽

Jacob R Patty

Keyword(s):

Water Balance ◽

Soil Water ◽

Agricultural Development ◽

Sunshine Duration ◽

Growing Season ◽

Climatic Data ◽

Climate Forecasts ◽

Water Surplus ◽

Land Water

Climate information/data of a region plays an important role in agricultural development in the region, because by utilizing the knowledge of the relationship between crops and climate, forecasts can be made of planting time, harvest time, drought (water deficit), flood (water surplus), pest attack and disease, determining the appropriate type of crop, and so on. The purpose of this study was to assess the presence of soil water and to determine the growing season in the Saumlaki area based on two rainfall conditions. This study used monthly rainfall data for 30 years (1990-2019) as well as other climatic data, such as air temperature, air humidity, sunshine duration and wind speed for 15 years (2005-2019). Computing of the water balance was carried out using Thornthwaite-Mather Method, and determination of growing season using soil water in optimum condition. Based on the calculation of the land water balance in the rainfall conditions there was a 75% chance of being surpassed by the groundwater deficit in the Saumlaki area which lasted for 6 months (June- November), whereas the value increases by 183 mm or 45.52% compared to normal conditions, that was from 402 mm to 585 mm. On the other hand, the groundwater surplus lasted only a month (May) and tended to decrease by 686 mm or 97.03% compared to normal conditions, from 707 mm to 21 mm. The optimum soil water content for plants in rainfall conditions was 75% chance of lasting for 6 months (January-June); 2 months shorter than the normal 8 months (December-July). In conditions of 75% chance of rainfall, the growing season in the Saumlaki area lasted for 7 months (December-June); a month shorter than the growing season in normal rainfall conditions of 8 months (December-July). Keywords: growing season, land water balance, rainfall, Saumlaki area ABSTRAK Informasi/data iklim suatu tempat berperan penting dalam pengembangan pertanian di wilayah tersebut, karena dengan memanfaatkan pengetahuan tentang hubungan antara tanaman dan iklim dapatlah dibuat prakiraan waktu tanam, waktu panen, kejadian kekeringan (defisit air), banjir (surplus air), serangan hama dan penyakit, penentuan jenis tanaman yang sesuai, dan sebagainya. Tujuan penelitian ini untuk menilai keberadaan air tanah dan menentukan musim tanam di Daerah Saumlaki pada dua kondisi curah hujan. Penelitian ini menggunakan data curah hujan bulanan selama 30 tahun (1990–2019) dan data iklim lainnya (suhu udara, kelembaban udara, lama penyinaran matahari kecepatan angin) selama 15 tahun (2005-2019). Perhitungan neraca air lahan menggunakan metode Thornthwaite-Mather, dan musim tanam ditentukan berdasarkan kondisi air tanah optimum. Berdasarkan perhitungan neraca air lahan pada kondisi curah hujan berpeluang 75% untuk dilampaui, defisit air tanah di daerah Saumlaki berlangsung selama selama 6 bulan (Juni-November) yaitu nilainya bertambah sebesar 183 mm (45,52%) dibandingkan kondisi normalnya, yaitu dari 402 mm menjadi 585 mm. Sebaliknya surplus air tanah berlangsung hanya sebulan (Mei) dan cenderung berkurang sebesar 686 mm (97,03%) dibandingkan kondisi normalnya, yaitu dari 707 mm menjadi 21 mm. Kadar air tanah yang optimum bagi tanaman pada kondisi curah hujan peluang 75% berlangsung selama 6 bulan (Januari-Juni); lebih pendek 2 bulan dibandingkan kondisi normalnya 8 bulan (Desember-Juli). Pada kondisi curah hujan peluang 75%, musim tanam di daerah Saumlaki berlangsung selama 7 bulan (Desember-Juni); sebulan lebih pendek dibandingkan musim tanam pada kondisi curah hujan normalnya 8 bulan (Desember-Juli). Kata kunci : curah hujan, daerah Saumlaki, musim tanam, neraca air lahan

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Estimation of direct evaporation from groundwater by using lysimeters in the Salar de Pedernales basin, Chilean Altiplano

Acta Universitaria ◽

10.15174/au.2020.2480 ◽

2020 ◽

Vol 30 ◽

pp. 1-14

Author(s):

Reynaldo Payano-Almánzar ◽

Dimitri Dionizis

Keyword(s):

Numerical Model ◽

Water Balance ◽

Shallow Groundwater ◽

Arid Zones ◽

Salt Flats ◽

Chilean Altiplano ◽

Semi Arid ◽

Model Water

In this research an estimation of the evaporation discharges from shallow groundwater in the Salar de Pedernales basin is made, using the lysimeter methodology. The analysis performed shows values between 1400 L·s-1 and 1900 L·s-1 with an uncertainty of error of 5% with respect to the average and between 11% and 47% in relation to the minimum and maximum values which can be compared by other studies where different tools have been used to calculate evaporation, such as: chamber, numerical model, water balance, Bowen relationships, Eddy correlations, and evaporation curves vs. altitude. The results confirm that lysimeters are appropriate tools for the determination of soil evapotranspiration and evaporation from shallow groundwater, whose components are key in the hydrology of endorheic basins, arid and semi-arid zones, for the management of protected natural spaces such as salt flats, waterholes, fertile plains, and bofedales.

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