(3) Strengthen farmland infrastructure and enhance soil drought resistance
Drought and water shortage are the main limiting factors for agricultural production. At present, the average annual precipitation in arid areas of China is generally below 300〜400 mm,if natural precipitation is stored to the maximum extent and soil moisture is effectively preserved,which is also an effective measure to prevent drought.In addition, the cultivation of fertility can promote the development of crop roots and increase the ability of "roots searching for water", so as to achieve the drought-resistant effect of "fertilizer regulating water".
(4) Improving the utilization rate of water resources
Research and application of modern technology and water-saving measures, such as artificial rainfall, drip irrigation, plastic film mulching, water conservation, to achieve water conservation, rational irrigation, scientific water use.
(5) Inhibition of evaporation and transpiration
Steam-inhibiting and drought-resistant chemicals have been widely used at home and abroad.Pharmaceuticals are agricultural liquid membranes,which principle is to use organic macromolecule substances to form liquid membranes with the participation of water and the function of regulating and controlling water molecule, so as to achieve the goal of absorbing water, holding water, inhibiting evaporation, reducing transpiration, saving water and effectively supplying water, improving the moisture retention rate and water use efficiency of precipitation, enhancing the drought resistance of crops under drought stress. Drought-resistant chemicals include water-retaining agent, drought-resistant agent and soil structure improver.Water retaining agent is mainly used for seed coating and seedling root coating; soil structure improver is mainly used for spraying soil protection after sowing and transplanting.
Drought early warning signals
The drought orange warning signal means that the drought index level is the third level of drought warning signal, moderate drought, and drought will continue. Some paddy fields can not maintain water layer; dry land crops have withered; reservoir water storage has decreased significantly, and water shortage has occurred in a few water shortage areas.
The red warning signal of drought means that the drought index level is above grade 4 (including grade 4), and severe drought will continue. Some streams and fish ponds have dried up, and the water level of small and medium reservoirs is close to dead storage capacity; a large number of paddy fields have been cracked, dryland crops have died and lost their income; water shortage has occurred in cities and towns.
Drought warning signals are divided into two levels, which are orange and red (Table 6-2)
Table 6-2 Classification of drought warning signals
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