scholarly journals NERACA AIR LAHAN UNTUK PENGEMBANGAN TANAMAN KELAPA SAWIT (Elaeis guinensis Jacq), DI KECAMATAN SANGKUB, KABUPATEN BOLAANG MONGONDOW UTARA

2017 ◽  
Vol 13 (3A) ◽  
pp. 33
Author(s):  
Silvana E. Kaeng ◽  
Johannes E.X. Rogi ◽  
Jantje ., Pongoh
Keyword(s):  
Water Balance ◽  
Simulation Model ◽  
Oil Palm ◽  
Secondary Data ◽  
Balance Model ◽  
Water Requirements ◽  
Model Method ◽  
Water Surplus ◽  
One Year ◽  
Land Water

This study aims to find out the water balance in Sangkub Sub-district, North Bolaang Mongondow Regency for oil palm cultivation with water balance simulation model developed by Handoko (1994) and Rogi (2002). The study was conducted from May - December 2016. This research uses simulation model method; the data used in this research is secondary data. The data analysis used run model of water balance of land and formula calculation of land water balance. The study found that the amount of water surplus from the run of the water balance model and calculations based on the formula in one year cannot meet the water requirements of oil palm crops, so that oil palm plantations cannot be cultivated in Sangkub Sub-district. This is due to the existence of rice cultivated crops prior to oil palm cultivation, where both plants require relatively large amount of water.

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

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

scholarly journals ESTIMASI NILAI LINGKUNGAN PERKEBUNAN KELAPA SAWIT DITINJAU DARI NERACA AIR TANAMAN KELAPA SAWIT (STUDI KASUS: PERKEBUNAN KELAPA SAWIT DI KECAMATAN DAYUN, KABUPATEN SIAK, PROPINSI RIAU)THE ESTIMATION OF OIL PALM PLANTATION ...

Agromet ◽  
2010 ◽  
Vol 24 (1) ◽  
pp. 23 ◽  
Author(s):  
Isa Teguh Widodo ◽  
Bambang Dwi Dasanto
Keyword(s):  
Water Balance ◽  
Oil Palm ◽  
Water Availability ◽  
Water Conservation ◽  
Contingent Valuation Method ◽  
Economic Value ◽  
Balance Model ◽  
Palm Tree ◽  
Conservation Program ◽  
Oil Palm Plantation

Dayun area is one of the centers of oil palm plantation in Siak Regency. State-owned company that develops oil palm plantation in Dayun is PT Perkebunan Nusantara V (PTPN V) which is the first company developing oil palm plantation in Siak Regency. The oil palm plantations cause various effects to the environment; one of them is the decreasing water availability for the water stakeholders. The decreasing water availability causes additional cost to the community. The objectives of this study were to determine the decreasing of water availability which was caused by oil palm plantation, and its cost to meet the needs of water. The study used water balance model by Thornwhite 1957 and Willingness to Pays (WTP) analysis using questionaire of Contingent Valuation Method (CVM) in Sawit Permai, Dayun Subdistrict, Siak Regency. The land cover, before and after, affects the water balance which impacts the water availability in Dayun. The decreasing water availability was comparable with the increasing water demand in oil palm plantation, equal to 67 mm/year. Oil palm plantation had greater runoff than that of forest. The need of water in oil palm plantation in Dayun was 42.728 liters/ha/day, with the daily need of a single palm tree equal to 0,012 m3/s. Based on the analysis of debt estimation, there is debt decreasing which indicates the decreasing water availability in Dayun, around 349 m3/s yearly. The estimated value of the environment for oil palm plantation by water resources consumption based on the difference of forest and oil palm plantation during the dry season (JJA) is equal to Rp 7.500.000. Average WTP for the water conservation program is Rp 26.400, with WTP maximum and minimum up to Rp 45.000 and Rp 5.000, respectively. The economic value of water conservation program is Rp 18.850.000/month.Dayun area is one of the centers of oil palm plantation in Siak Regency. State-owned company that develops oil palm plantation in Dayun is PT Perkebunan Nusantara V (PTPN V) which is the first company developing oil palm plantation in Siak Regency. The oil palm plantations cause various effects to the environment; one of them is the decreasing water availability for the water stakeholders. The decreasing water availability causes additional cost to the community. The objectives of this study were to determine the decreasing of water availability which was caused by oil palm plantation, and its cost to meet the needs of water. The study used water balance model by Thornwhite 1957 and Willingness to Pays (WTP) analysis using questionaire of Contingent Valuation Method (CVM) in Sawit Permai, Dayun Subdistrict, Siak Regency. The land cover, before and after, affects the water balance which impacts the water availability in Dayun. The decreasing water availability was comparable with the increasing water demand in oil palm plantation, equal to 67 mm/year. Oil palm plantation had greater runoff than that of forest. The need of water in oil palm plantation in Dayun was 42.728 liters/ha/day, with the daily need of a single palm tree equal to 0,012 m3/s. Based on the analysis of debt estimation, there is debt decreasing which indicates the decreasing water availability in Dayun, around 349 m3/s yearly. The estimated value of the environment for oil palm plantation by water resources consumption based on the difference of forest and oil palm plantation during the dry season (JJA) is equal to Rp 7.500.000. Average WTP for the water conservation program is Rp 26.400, with WTP maximum and minimum up to Rp 45.000 and Rp 5.000, respectively. The economic value of water conservation program is Rp 18.850.000/month.

WILAYAH SURPLUS DAN DEFISIT AIR DI SENTRA PRODUKSI PADI SULAWESI UTARA MENGGUNAKAN MODEL NERACA AIR

EUGENIA ◽  
2012 ◽  
Vol 18 (3) ◽  
Author(s):  
J. H. Panelewen ◽  
J. E.X. Rogi ◽  
W. Rotinsulu
Keyword(s):  
Data Analysis ◽  
Water Balance ◽  
Geographical Information Systems ◽  
Water Shortage ◽  
Water Balance Model ◽  
Geographical Information ◽  
Balance Model ◽  
Rainfall Trend ◽  
North Sulawesi ◽  
Water Surplus

ABSTRACT   The research was conducted in the field and laboratory. Fieldwork in paddy rice production center was done to collect geographical coordinates while data analysis was conducted in the Laboratory of Ecosystem Modelling, Faculty of Agriculture, Sam Ratulangi University. Laboratory analysis was done to validate water balance model and to develop water surplus dan water shortage maps. This research was done during August 2012. Data collection included identification, inventory and data analysis. Then it continued with developing digital maps using Geographical Information Systems (GIS) for water balance model. Model inputs included climatic variables (rainfall, temperature, humidity, sunlight, and windspeed), ground water content and leaf area index. Parameter inputs included crop variety and location. Model simulation indicated that rainfall trend in North Sulawesi has increased especially in Januari, April dan November. Conversely, a decrease rainfall trend was ocurred in February and September. Spatial map showed that water surplus ocurred in Minahasa Selatan, Bolaang Mongondow, Bolang Mongondow Utara and Bolaang Mongondow Selatan. On the other hand, water shortage in North Sulawesi was experienced in October. Keywords : geographical information systems, water balance model   ABSTRAK   Penelitian ini dilakukan di lapangan dan laboratorium. Kerja lapangan di sentra produksi padi dilakukan untuk mengumpulkan data koordinat geografis sedangkan data analisis dilakukan di Laboratorium Model Ekosistem, Fakultas Pertanian, Universitas Sam Ratulangi. Analisis Laboratorium dilakukan untuk memvalidasi model neraca air dan untuk mengembangkan peta kelebihan dan kekurangan air. Penelitian ini dilakukan selama bulan Agustus 2012. Pengumpulan data meliputi identifikasi, inventarisasi dan analisis data. Kemudian dilanjutkan dengan mengembangkan peta digital dengan menggunakan Sistem Informasi Geografis (SIG) untuk model neraca air. Model input meliputi variabel iklim (curah hujan, suhu, kelembaban, sinar matahari, dan kecepatan angin), kadar air tanah dan indeks luas daun. Parameter input meliputi berbagai varietas tanaman dan lokasi. Model simulasi menunjukkan bahwa curah hujan tren di Sulawesi Utara telah meningkat terutama pada Januari, April dan November. Sebaliknya, penurunan curah hujan tren yang terjadi pada bulan Februari dan September. Spasial peta menunjukkan bahwa surplus air terjadi di Minahasa Selatan, Bolaang Mongondow, Bolang Mongondow Utara dan Bolaang Mongondow Selatan. Di sisi lain, kekurangan air di Sulawesi Utara dialami pada bulan Oktober. Kata kunci: sistem informasi geografis, model neraca air

scholarly journals ESTIMATIVA DE EVAPOTRANSPIRAÇÃO E COEFICIENTE DE CULTURA DO TOMATEIRO INDUSTRIAL UTILIZANDO O ALGORITMO SAFER

Irriga ◽  
2018 ◽  
Vol 22 (3) ◽  
pp. 629-640 ◽  
Author(s):  
Déborah Lidya Sales ◽  
José Alves Júnior ◽  
Derblai Casaroli ◽  
Adão Wagner Pego Evangelista ◽  
João Mauricio Fernandes Souza
Keyword(s):  
Energy Balance ◽  
Water Balance ◽  
Water Content ◽  
Soil Water Content ◽  
Satellite Images ◽  
Reference Evapotranspiration ◽  
Crop Coefficient ◽  
Balance Model ◽  
Local Dynamic ◽  
Water Requirements

ESTIMATIVA DE EVAPOTRANSPIRAÇÃO E COEFICIENTE DE CULTURA DO TOMATEIRO INDUSTRIAL UTILIZANDO O ALGORITMO SAFER  DEBORAH LIDYA ALVES SALES¹; JOSÉ ALVES JÚNIOR²; DERBLAI CASAROLI²; ADÃO WAGNER PEGO EVANGELISTA² E JOÃO MAURICIO FERNANDES SOUZA3 ¹Profª. Mestre da Faculdade Metropolitana de Anápolis FAMA/Av. Fernando Costa, 49 - Vila Jaiara St. Norte, Anápolis - GO, 75064-780, Brasil, email: [email protected]²,Prof. Doutor do Núcleo de Pesquisas em Clima e Recursos Hídricos do Cerrado – Escola de Agronomia - Universidade Federal de Goiás, Rodovia Goiânia / Nova Veneza, Km 0, Goiânia, Goiás, CEP: 74690-900, Brasil,  email: [email protected], [email protected], [email protected]. Doutor do Centro Universitário de Anápolis – UniEVANGÉLICA/Av. Universitária Km. 3, 5 - Cidade Universitária, Anápolis - GO, 75083-515, Brasil,  email:[email protected]  1 RESUMO Objetivo do estudo foi estimar a evapotranspiração atual (ETa), e os respectivos coeficientes de cultura de dois híbridos de tomateiro industrial pelo modelo de balanço de energia utilizando o algoritmo SAFER, com comparação com tradicional método micrometeorológico utilizando evapotranspiração de referência (ETo), com os Kcs recomendados pela FAO 56 e EMBRAPA. O estudo foi realizado na Fazenda cabeceira do Piracanjuba, no município de Silvânia-GO, no período de maio a agosto de 2015. Além disso, foi monitorado o potencial de água na folha e o conteúdo de água no solo pelo balanço hídrico dinâmico local. Os valores de Kcs estimados pelo método do SAFER apresentou significante correlação com os métodos FAO 56 e Embrapa (FAO 56, R² = 0,98; Embrapa, R² = 0,95). A ETc estimada pelo método do SAFER apresentou significante correlação com os métodos micrometeorológicos (FAO 56, R2 = 0,97; Embrapa, R2 = 0,97), podendo este ser utilizado para estimativa da ETa na região. Palavra-chaves: necessidade hídrica, imagens de satélite, balanço de energia, irrigação  SALES, D. L. A.; ALVES JÚNIOR, J.; DERBLAI, C.; SOUZA, J. M. F. EVAPOTRANSPIRATION ESTIMATE AND CROP COEFFICIENT OF INDUSTRIAL TOMATOES USING THE SAFER ALGORITHM  2 ABSTRACT The objective of this study was to estimate the current evapotranspiration and the respective cultivation coefficients of two industrial tomato hybrids by the energy balance model using the SAFER algorithm, using a traditional micrometeorological method using ETo (Penman-Monteith) reference evapotranspiration with the Kcs recommended by FAO 56 and EMBRAPA. The study was carried out at the Piracanjuba head farm, in the municipality of Silvânia, GO, from May to August 2015. In addition, the potential of leaf water and soil water content was monitored by the local dynamic water balance. The Kcs estimated by the SAFER method presented a significant correlation with the FAO 56 and Embrapa methods (FAO 56, R² = 0.98, Embrapa, R² = 0.95). The ETc estimated by the SAFER method showed a significant correlation with the micrometeorological methods (FAO 56, R2 = 0.97, Embrapa, R2 = 0.97), which could be used to estimate ETa in the region. Keywords: water requirements; satellite images; energy balance and irrigation.

Improved large-scale crop water requirement estimation through new high-resolution reanalysis dataset

2020 ◽  
Author(s):  
Matteo Rolle ◽  
Stefania Tamea ◽  
Pierluigi Claps
Keyword(s):  
Soil Moisture ◽  
Water Balance ◽  
Large Scale ◽  
Water Requirement ◽  
Crop Water Requirement ◽  
Balance Model ◽  
Blue Water ◽  
Crop Water ◽  
Water Requirements ◽  
Reanalysis Dataset

<p>Estimation of crop water needs is essential to understand the role of agriculture in the water balance modeling at various scales. In turn, this is relevant for water management purposes and for the fulfilling of water-related environmental regulations. In this study, a comprehensive assessment of crop water requirement at large scale is presented, both in terms of rainfall (green water) and irrigation (blue water).</p><p>A water-balance model is built to provide estimates of actual evapotranspiration and accompanying soil moisture by using high space-time resolution data. The new ERA5 reanalysis dataset, published by the ECMWF within the Copernicus monitoring system and obtained from satellite data and ground measurements, provides the precipitation and temperature input variables to the model. Data available at the hourly time scale are all aggregated on a daily scale and used in the water balance model over  a grid of cultivated areas from the MIRCA2000 dataset. Cultivated areas are available for 26 crops for year 2000 at a spatial resolution of 5 arcmin (about 9 km at the Equator). Data from MIRCA2000 are separated between rainfed areas and areas equipped for irrigation and are characterized by specific monthly calendars of the crop growing seasons.</p><p>The model performs the daily soil water balance throughout the whole year, considering all crops at their growth stage and assuming as initial condition at each crop sowing date a monthly average soil moisture. Results quantify the volumes of green and blue water necessary for crop growth and describe the spatial variability of the water requirements of each individual crop. The high spatial and temporal resolution of Copernicus ERA5 data enables a great improvement in the characterization of hydro-climatic forcings with respect to previous assessments and a greater accuracy in the crop water requirement estimates.</p><p>Finally, the knowledge of water requirements is an important step to quantify the irrigation volumes used in agriculture, on which there is a high uncertainty and little spatially distributed information. The model proposed enables the investigation of spatio-temporal variability associated to varying meteorological forcings and of the effects of different irrigation techniques, enabling an improved management of water resources.</p>

Risk of venous thromboembolism following surgical treatment of superficial venous incompetence

VASA ◽  
2017 ◽  
Vol 46 (6) ◽  
pp. 484-489 ◽  
Author(s):  
Tom Barker ◽  
Felicity Evison ◽  
Ruth Benson ◽  
Alok Tiwari
Keyword(s):  
Venous Thromboembolism ◽  
Varicose Vein ◽  
Lower Incidence ◽  
Varicose Veins ◽  
Secondary Data ◽  
Foam Sclerotherapy ◽  
Increased Risk ◽  
Significant Difference ◽  
Chi Squared ◽  
One Year

Abstract. Background: The invasive management of varicose veins has a known risk of post-operative deep venous thrombosis and subsequent pulmonary embolism. The aim of this study was to evaluate absolute and relative risk of venous thromboembolism (VTE) following commonly used varicose vein procedures. Patients and methods: A retrospective analysis of secondary data using Hospital Episode Statistics database was performed for all varicose vein procedures performed between 2003 and 2013 and all readmissions for VTE in the same patients within 30 days, 90 days, and one year. Comparison of the incidence of VTEs between procedures was performed using a Pearson’s Chi-squared test. Results: In total, 261,169 varicose vein procedures were performed during the period studied. There were 686 VTEs recorded at 30 days (0.26 % incidence), 884 at 90 days (0.34 % incidence), and 1,246 at one year (0.48 % incidence). The VTE incidence for different procedures was between 0.15–0.35 % at 30 days, 0.26–0.50 % at 90 days, and 0.46–0.58 % at one year. At 30 days there was a significantly lower incidence of VTEs for foam sclerotherapy compared to other procedures (p = 0.01). There was no difference in VTE incidence between procedures at 90 days (p = 0.13) or one year (p = 0.16). Conclusions: Patients undergoing varicose vein procedures have a small but appreciable increased risk of VTE compared to the general population, with the effect persisting at one year. Foam sclerotherapy had a lower incidence of VTE compared to other procedures at 30 days, but this effect did not persist at 90 days or at one year. There was no other significant difference in the incidence of VTE between open, endovenous, and foam sclerotherapy treatments.

scholarly journals Study on the regional characteristics during foam flooding by population balance model

2020 ◽  
pp. 014459872098361
Author(s):  
Zhongbao Wu ◽  
Qingjun Du ◽  
Bei Wei ◽  
Jian Hou
Keyword(s):  
Numerical Simulation ◽  
Simulation Model ◽  
Oil Recovery ◽  
Population Balance ◽  
Growth Zone ◽  
Balance Model ◽  
Population Balance Model ◽  
Liquid Ratio ◽  
One Dimensional ◽  
Foam Flooding

Foam flooding is an effective method for enhancing oil recovery in high water-cut reservoirs and unconventional reservoirs. It is a dynamic process that includes foam generation and coalescence when foam flows through porous media. In this study, a foam flooding simulation model was established based on the population balance model. The stabilizing effect of the polymer and the coalescence characteristics when foam encounters oil were considered. The numerical simulation model was fitted and verified through a one-dimensional displacement experiment. The pressure difference across the sand pack in single foam flooding and polymer-enhanced foam flooding both agree well with the simulation results. Based on the numerical simulation, the foam distribution characteristics in different cases were studied. The results show that there are three zones during foam flooding: the foam growth zone, stable zone, and decay zone. These characteristics are mainly influenced by the adsorption of surfactant, the gas–liquid ratio, the injection rate, and the injection scheme. The oil recovery of polymer-enhanced foam flooding is estimated to be 5.85% more than that of single foam flooding. Moreover, the growth zone and decay zone in three dimensions are considerably wider than in the one-dimensional model. In addition, the slug volume influences the oil recovery the most in the foam enhanced foam flooding, followed by the oil viscosity and gas-liquid ratio. The established model can describe the dynamic change process of foam, and can thus track the foam distribution underground and aid in optimization of the injection strategies during foam flooding.

scholarly journals Sensitivity of groundwater recharge using climatic analogues and HYDRUS-1D

2012 ◽  
Vol 16 (8) ◽  
pp. 2485-2497 ◽  
Author(s):  
B. Leterme ◽  
D. Mallants ◽  
D. Jacques
Keyword(s):  
Water Balance ◽  
Groundwater Recharge ◽  
Potential Evapotranspiration ◽  
Future Climate ◽  
Annual Precipitation ◽  
Balance Model ◽  
Subtropical Climate ◽  
Northern Spain ◽  
Near Surface ◽  
Hydrus 1D

Abstract. The sensitivity of groundwater recharge to different climate conditions was simulated using the approach of climatic analogue stations, i.e. stations presently experiencing climatic conditions corresponding to a possible future climate state. The study was conducted in the context of a safety assessment of a future near-surface disposal facility for low and intermediate level short-lived radioactive waste in Belgium; this includes estimation of groundwater recharge for the next millennia. Groundwater recharge was simulated using the Richards based soil water balance model HYDRUS-1D and meteorological time series from analogue stations. This study used four analogue stations for a warmer subtropical climate with changes of average annual precipitation and potential evapotranspiration from −42% to +5% and from +8% to +82%, respectively, compared to the present-day climate. Resulting water balance calculations yielded a change in groundwater recharge ranging from a decrease of 72% to an increase of 3% for the four different analogue stations. The Gijon analogue station (Northern Spain), considered as the most representative for the near future climate state in the study area, shows an increase of 3% of groundwater recharge for a 5% increase of annual precipitation. Calculations for a colder (tundra) climate showed a change in groundwater recharge ranging from a decrease of 97% to an increase of 32% for four different analogue stations, with an annual precipitation change from −69% to −14% compared to the present-day climate.

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