Evaluation of Rainfall Tendency for the Twentieth Century over Indira Sagar Region in Central India

The study investigates long-term changes in annual and seasonal rainfall patterns in the Indira Sagar Region of Madhya Pradesh, India, from 1901 to 2010. Agriculture sustainability, food supply, natural resource development, and hydropower system reliability in the region rely heavily on monsoon rainfall. Monthly rainfall data from three stations (East Nimar, Barwani, and West Nimar) were analyzed. Initially, the pre-whitening method was applied to eliminate serial correlation effects from the rainfall data series. Subsequently, statistical trends in annual and seasonal rainfall were assessed using both parametric (student-t test) and non-parametric tests [Mann-Kendall, Sen’s slope estimator, and Cumulative Sum (CUSUM)]. The magnitude of the rainfall trend was determined using Theil-Sen’s slope estimator. Spatial analysis of the Mann-Kendall test on an annual basis revealed a statistically insignificant decreasing trend for Barwani and East Nimar and an increasing trend for West Nimar. On a seasonal basis, the monsoon season contributes a significant percentage (88.33%) to the total annual rainfall. The CUSUM test results indicated a shift change detection in annual rainfall data for Barwani in 1997, while shifts were observed in West and East Nimar stations in 1929. These findings offer valuable insights into regional rainfall behavior, aiding in the planning and management of water resources and ecological systems.

Uncertainty of soil erosion modelling using open source high resolution and aggregated DEMs

Digital Elevation Model （DEM） is one of the important parameters for soil erosion assessment. Notable uncertainties are observed in this study while using three high resolution open source DEMs. The Revised Universal Soil Loss Equation （RUSLE） model has been applied to analysis the assessment of soil erosion uncertainty using open source DEMs （SRTM, ASTER and CARTOSAT） and their increasing grid space （pixel size） from the actual. The study area is a part of the Narmada river basin in Madhya Pradesh state, which is located in the central part of India and the area covered 20,558 km2. The actual resolution of DEMs is 30 m and their increasing grid spaces are taken as 90, 150, 210, 270 and 330 m for this study. Vertical accuracy of DEMs has been assessed using actual heights of the sample points that have been taken considering planimetric survey based map （toposheet）. Elevations of DEMs are converted to the same vertical datum from WGS 84 to MSL （Mean Sea Level）, before the accuracy assessment and modelling. Results indicate that the accuracy of the SRTM DEM with the RMSE of 13.31, 14.51, and 18.19 m in 30, 150 and 330 m resolution respectively, is better than the ASTER and the CARTOSAT DEMs. When the grid space of the DEMs increases, the accuracy of the elevation and calculated soil erosion decreases. This study presents a potential uncertainty introduced by open source high resolution DEMs in the accuracy of the soil erosion assessment models. The research provides an analysis of errors in selecting DEMs using the original and increased grid space for soil erosion modelling.

Future changes in rainfall, temperature and reference evapotranspiration in the central India by least square support vector machine

Climate change affects the environment and natural resources immensely. Rainfall, temperature and evapotranspiration are major parameters of climate affecting changes in the environment. Evapotrans- piration plays a key role in crop production and water balance of a region, one of the major parameters affected by climate change. The reference evapotranspiration or ETo is a calculated parameter used in this research. In the present study, changes in the future rainfall, minimum and maximum temperature, and ETo have been shown by downscaling the HadCM3 （Hadley Centre Coupled Model version 3） model data. The selected study area is located in a part of the Narmada river basin area in Madhya Pradesh in central India. The downscaled outputs of projected rainfall, ETo and temperatures have been shown for the 21st century with the HADCM3 data of A2 scenario by the Least Square Support Vector Machine （LS-SVM） model. The efficiency of the LS-SVM model was measured by different statistical methods. The selected predictors show considerable correlation with the rainfall and temperature and the application of this model has been done in a basin area which is an agriculture based region and is sensitive to the change of rainfall and temperature. Results showed an increase in the future rainfall, temperatures and ETo. The temperature increase is projected in the high rise of minimum temperature in winter time and the highest increase in maximum temperature is projected in the pre-monsoon season or from March to May. Highest increase is projected in the 2080s in 2081-2091 and 2091-2099 in maximum temperature and 2091-2099 in minimum temperature in all the stations. Winter maximum temperature has been observed to have increased in the future. High rainfall is also observed with higher ETo in some decades. Two peaks of the increase are observed in ETo in the April-May and in the October. Variation in these parameters due to climate change might have an impact on the future water resource of the study area, which is mainly an agricultural based region, and will help in proper planning and management.

温室微气候环境与蒸散发模拟技术综述

通过温室作物生产,人工驯化植物已经彻底改变了世界各地的农业耕作制度。选择合适的温室技术和用户友好的蒸散量(ETc)模型可以优化作物水分利用。温室微气候环境具有近零风速和低辐射等特点,由于温室内高温和高湿,蒸腾作用较低。将温室微气候与适当的ETc模型相匹配可以优化作物水分利用效率,这是弥合各种先进ETc模型的应用与温室作物生产者之间距离的原因之一。更实用的温室ETc模型将会在更大的温室作物生产者群体中迅速传播,而ETc估算技术进步的可能性也将增加。温室系统对增加和实现粮食可持续生产的贡献必须通过改进现有温室管理模式来实现。粮农组织建议使用参考蒸散量(ET0)和作物系数(Kc)值的乘积来确定作物需水量的标准方法。该方法也可用于温室栽培系统,然而,关于温室条件下ET0或ETc测量方法研究还相当有限。在不同类型温室条件下,比较ET0或ETc模型性能的研究也很少。该综述强调了温室环境控制技术与ET0或ETc模型之间的联系,以及ET0或ETc测量中,现有知识和方法如何实际提高温室农业的可持续性。该综述旨在评估和总结目前可用的ET0或ETc估算模型,以及在各种类型温室中使用的ET0或ETc模型的准确性与适用性。

Overview of modelling techniques for greenhouse microclimate environment and evapotranspiration

Domestication of plants by man through greenhouse crop production has revolutionized agricultural farming systems worldwide.Selecting the appropriate greenhouse technology together with the user-friendly evapotranspiration(ETc)model can optimize crop water use.The greenhouse microclimate environment has nearly zero wind speed and low radiation,hence low transpiration due to high temperature and humidity.Therefore,matching the greenhouse microclimate with the appropriate ETc model will certainly optimize crop water use efficiency since water is becoming a scarce resource globally,more so in the greenhouse environment.This is one of the main reasons why the gap between the dissemination of various advanced ETc models and the application by the greenhouse crop producers’community needs to be bridged.The likelihood or chances of rapidly disseminating and adopting advances in ETc estimating technology by a larger greenhouse crop producers community will increase if greenhouse ETc models become more user-friendly and available.The contribution of the greenhouse system to increased and sustainable food production must come through improved disseminating,adopting and use of existing greenhouse ETc models.FAO recommends a standard approach for the determination of crop water requirements utilizing the product of reference evapotranspiration(ET0)and crop coefficient(Kc)values.The FAO approach can also be used in greenhouse cultivation systems.However,studies connecting greenhouse technologies and methodologies for measuring ET0 or ETc in greenhouses are not available.There are also few studies undertaken that compared the performance of ET0 or ETc models under different categories of greenhouse conditions.In this review,a link between greenhouse technology and ET0 model or ETc model,and how existing knowledge and methodologies in ET0 or ETc measurements can actually enhance the sustainability of greenhouse farming have been highlighted.The categories of greenhouses,equipment commonly used,and the data collected for ET0 and ETc measurements have been established in the article.This review aimed to evaluate and summarize ET0 and ETc models currently available and being used in the various greenhouse categories.The accuracy assessment levels of the ET0 models about the category of the greenhouse microclimate environment were carried out.