Cas 89604-92-2,Chemical Products,Cas 151096-09-2,Industrial Chemicals Mingya Trading PTE.L , https://www.mingyachem.com
Rice is the staple food crop in Guangdong, and rice paddy fields are bound to be the absolute majority of irrigation water for a long time now and henceforth, so it is a key crop for the study of irrigation efficiency. The irrigation efficiency of rice refers to the increase in the yield of reasonably irrigated paddy fields relative to the non-irrigated “Wang Tian Tianâ€, and the changes mainly depend on natural rainfall conditions. Due to the uneven spatial and temporal distribution of rainfall in this province, rainfall is used by crops and even yields. The situation is complex and changeable. This is closely related to natural rainfall and is similar to a random process of change. It should be based on mathematical statistics principles for many years. Series analysis to find out its regularity. Through many years of experiments, we have conducted systematic research on the process of rainfall changes in the experimental area, the use of rainfall in paddy fields, and the relationship between soil water and crop growth and yield, so that the atmospheric water-soil water-crop organic connection Based on this, the “Relationship between Water Deficit in Paddy Field and Yield†was established, and the analysis method for crop irrigation efficiency was proposed. The establishment of the correlation between water deficit and yield in paddy fields reveals the quantitative relationship between soil water and crop yields. It provides a scientific and relatively simple method for studying the irrigation benefits of all regions and crops in the province.
How to analyze: Take Meixian County as an example, the analysis method and steps of rice irrigation benefits are as follows: a) Data collection This case collected local daily rainfall and surface water evaporation data for 47 years from 1953 to 1999. b) Determine the main analysis indicators for various analysis indicators include: survey and identification of crop cultivation methods, crop varieties, growth period, etc.; "to determine the irrigation system, we should choose the local water-saving, large-scale implementation of the paddy field irrigation system, including the reproductive stages The lower limit of irrigation, the upper limit of rainwater storage, etc.; estimation method of rice water requirement (according to the research results of Guangdong Academy of Agricultural Sciences, using empirical formulas, inferred from surface water evaporation intensity); determine the average leakage strength of local paddy fields. c) programming, calculation based on The principle of soil moisture balance was calculated and the calculation parameters were input into the computer to analyze the daily balance of soil moisture in the “Wang Tian Tian†field, and the daily soil moisture content was obtained.d) Rice field year by year (in the early and late rice) Average Deficit Coefficient This example analyzes the average depletion coefficient of paddy fields from 1953 to 1999 year by year. The results show that: Early rice was rich in rainfall and distributed evenly. The average dehydration coefficient of Wangtiantian was 17.7 for many years; late rice had less rainfall. The "depression of the Tiantian" is severe, and the average annual deficit coefficient is 44.5. Double-season rice (early and late rice) The average dehydration coefficient for many years is 33.4. e) The “Wangtiantian†yield index is estimated based on the “relationship between depletion of water in paddy fields and yieldâ€, and the “Wangtiantian†yield index is calculated year by year. During the estimation process, it should be based on the The actual state of the soil moisture changes day by day, combined with experience, to perform local corrections on specific conditions.The results of this case analysis show that the multi-year average yield index was 62.2 for early rice and 18.7 for late rice, and the double-cropping rice yield index was 41.4. Irrigation Benefit Analysis: Irrigation The rate of increase in crop yield represents the benefit of crop irrigation, which is the yield increase of rational irrigation relative to non-irrigation, and is usually expressed as a percentage increase. According to the “Irrigation Test Regulations,†crop irrigation efficiency (ie, irrigation increase) is calculated using a formula. The ratio (%) of the benefits gained after irrigation to the total production benefits after irrigation is called “irrigation ratioâ€, ie, the total production after irrigation is regarded as “irrigated water†(or “engineering waterâ€) and natural water. The total production benefit of the project, and the total output after irrigation minus the output of the Tiantian field that depends on "natural water" is used as the increase in the output of "irrigated water". The percentage of total production compared with irrigation benefit ratio.
In practical applications, the analysis of the benefits of project irrigation generally uses a soil moisture recorder, and then uses the benefit "aspect factor" method. That is, based on the total yield increase (increased yield or output value per unit area), multiplying the "diluted coefficient" of irrigation efficiency (generally the ratio of irrigation efficiency to total efficiency) and the sown area of ​​crops. Guangdong has a relatively high rainfall and relies on natural rainfall. Crops also have a certain amount of crops, but the output is high, low, or no crop is harvested. Farmers can neither control nor predict them. Therefore, as an agricultural infrastructure, the irrigation project is a basis for maintaining the stability of the rural society and the steady economic development of the crop while maintaining stable yields and high yields. Therefore, the evaluation of irrigation benefits should first be measured from social benefits; secondly, Most agricultural production technologies must be implemented under the conditions of irrigation guarantee. In this sense, the benefits of irrigation also increase with the improvement of agricultural production technology. Therefore, from an economic point of view, land with irrigation and no irrigation conditions is evaluated. The comparison of productivity is more reasonable, or the improvement of comprehensive agricultural production benefits such as land productivity and labor productivity brought about by irrigation should be used as the basis for evaluating irrigation efficiency.
Based on the field experiment, this study studied the relationship between rainfall and soil water, the relationship between soil water and crop growth, and organically linked atmospheric water, soil water, and crops to establish their mutual relationship and further analysis. The indicator for evaluating the irrigation efficiency of rice in the area was proposed. As a relatively simple and fast research method and research method, it can be applied to all regions and crops in the province to calculate the irrigation benefits that can cover the whole province and various major crops. The results of this project directly serve for the planning and design of irrigation projects. The use of advanced computer technology to analyze and study scientific and reasonable crop irrigation benefits fills the gap in this aspect of our province, and has strong operability. It can be directly applied or used in similar technology fields and has practical significance. Because the test results are obtained under certain conditions, it is inevitable that there are limitations in the time domain and the region. Therefore, conditions should be created in the future and field trials should be continued to make it perfect day by day. On the basis of the completion of the "from fine to fine" process, more in line with scientific "precision" requirements.
In today's ever-increasing contradiction between water supply and demand, agricultural irrigation must continuously improve water use efficiency and water use efficiency. Giving priority to benefits is an important principle in the development of social economy. Scientifically and reasonably assessing the irrigation efficiency of crops is the basis and prerequisite for the feasibility study of irrigation area construction and technological transformation, the optimization of engineering projects and programs, and the management quality inspection and assessment. It is also the scientific basis for the implementation of water-saving irrigation and evaluation of water-saving benefits. . However, for a variety of reasons, for a variety of reasons, the research on crop irrigation efficiency has obviously lagged behind the development of the economy and other science and technology. The evaluation of irrigation benefits lacks scientific standards, and the values ​​are confusing. Even in the same region and during the same period, the use of soil moisture Speed ​​measurement instrument for moisture measurement, and then determine the irrigation situation, the results of the analysis of irrigation efficiency are also very different, this situation not only inconvenience to the technical review, but also affect the government's decision-making and causing errors. This has aroused the attention of the relevant technical departments in our province and commissioned the Guangdong Provincial Academy of Water Sciences to carry out experimental research on crop irrigation benefits. Through scientific experiments, it seeks simple and feasible analysis methods for crop irrigation benefits, enhances objectivity and science, thereby reducing blindness or loss due to distortion of benefits.