Panjin City records: "This land was submerged by ancient shallow seas in Proterozoic about 600 million to 900 million years ago. Due to the influence of Wutai Mountain movement, volcanic activity is frequent here, and a large amount of magma is immersed and rises to the land. Later, the Jixian movement reduced Panjin area to shallow sea, which was composed of sedimentary shallow sea limestone, marl and shale.
In Mesozoic, about 800-230 million years ago, influenced by Indosinian movement and Yanshan movement, it rose to land in the early Mesozoic and was in a weathering and erosion environment. After the middle Mesozoic, Panjin area experienced many ups and downs, accompanied by volcanic eruption. The sedimentary environment is continental gravel, gravel, sandstone, shale, pyroclastic rock and andesite in inland lakes.
After entering the Quaternary, due to the influence of Himalayan movement, the contour lines of the lower Liaohe Plain changed very frequently. After the Middle Pleistocene, there were three times of seawater immersion in the Lower Liaohe Plain. Therefore, at present, there are three sets of marine sedimentary strata and land-sea alternating strata in Daliaohekou and Liaohekou. In the later period, due to the continuous decline of the plain, the low hills on the east and west sides were relatively uplifted and denuded, and continental debris was continuously accumulated in the coastal estuary, and the coastline moved southward, and coastal beaches were formed one after another.
Since Mesozoic, a series of large regional faults in the northeast and the north have cut the ancient structures before Mesozoic, and formed a series of open and gentle fault-depression structures in the northeast and northeast, showing a new structural pattern of east-west zoning and north-south blocking.
Panjin is a Cenozoic sedimentary basin formed by Yanshan Movement. After a long period of river alluvial, diluvial, marine and aeolian deposits, it is constantly covered by deep Quaternary loose sediments with high salinity. "("Panjin City Records "comprehensive volume pp. 356-352)
Panjin is located at the mouth of Liaohe River, the center of Liaohe Delta. As a retreat plain, it is formed by alluvial black soil, sandy soil and loess in the upper reaches of Daliao River, Liaohe River and Daling River, namely Jilin, Inner Mongolia, Liaoning and Hebei provinces. Its average elevation is 5.3 meters, and the lowest elevation is only 0.3 meters. This forms a unique law of water and salt movement in Panjin, and serious soil alkali return is the main feature of water and salt movement in Panjin. Therefore, Panjin's unique soil quality is characterized by saline-alkali topsoil with a PH value of 8.0-8.9, high viscosity in the lower layer and poor surface water permeability. This soil is characterized by starch morphology and molecular structure formed by glycosidic bond polymerization during rice growth.
The composition of soil is the composition of crops. After more than a hundred years of exploration and cultivation, the soil conditions in Panjin are as follows: the land area of Panjin is 3.78 million mu. The total area of "paddy soil" is1405,700 mu, accounting for 37.2% of the total soil area (mainly distributed in the coastal plain of Panshan County, Dawa County and the Liaohe River). Among them, saline paddy soil 1.386 million mu, accounting for 98.6% of the total area of paddy soil. Groundwater level is 0.3- 1.6m, water salinity 1-20g, PH value is 8.0-8.9, organic matter content 1.0%-3.0%, total nitrogen is 0.055%-0. 165%, and total phosphorus is 0. The area of "flooded paddy soil" is 65,438 0.97 million mu, accounting for 65,438 0.4% of the total paddy soil area (distributed in Dahuang, Goldman Sachs Town of Panshan County and Xi 'an and Dongfeng areas of Dawa County). The soil salinity is less than 0. 1%, the groundwater level is 1-2m, the water salinity is at the bottom of 1g/L, the PH value is 8.0-8.9, the organic matter content is 0.9%-3.05%, and the total nitrogen content is 0.055%-0.224%. The specific original ecology and reformed soil conditions in Panjin provide basic conditions for the growth and reproduction of rice and the formation of its characteristics. Water is another key factor in rice cultivation. Water quality and scientific water use have great influence on the growth and quality of rice. Panjin is the lower tip of nine major rivers, with as many as 2 1 river in the territory. Facing the water regime, water regime and the law of water and salt movement in Panjin, Panjin has built a scientific and complete water conservancy facilities system, storing and adjusting water well, aiming at rice growth, so as to achieve irrigation and drainage, easy salt pressure and alkali control. At the same time, master the water regime and water regime in the basin and take good measures to avoid pollution.
Irrigation water for paddy fields in Panjin is mainly taken from Shuangtaizi River. The reason is that the trunk length of Shuangtaizi River system is 1.394 km, which originates from Tushan and seven old in the north of Hebei Province, and flows through the grasslands of Zhaowudamung and Zhelimu League in Inner Mongolia, the mountain wilderness in the south half of Jilin Province and the mountainous area in the northwest of Liaoning Province. There are not many big cities, small and medium-sized cities and large industries in the basin. Shuangtaizi River has strong seasonality, and it is semi-dry most of the year, with abundant water only in spring and summer. Therefore, the Shuangtaizi River system is less polluted than the Daliao River system.
Effective use of Shuangtaizi River in spring and summer. Spring flood, also known as peach blossom flood, is caused by the melting of winter snow in the 228,900-square-kilometer river basin. Using spring flood water to meet all the water demand of soaking and transplanting in Panjin paddy field. Every July and August, the Shuangtaizi River basin enters the rainy season, and the rivers in the territory skyrocket, causing summer floods. This is the peak of water demand for rice growth. The soaring river not only meets the needs of irrigation, but also provides reservoir water storage. Panjin City has only 407 1 km2, and there are seven reservoirs: Liao Bin Reservoir, Delta Reservoir, Gelou Reservoir, Rongxing Reservoir, Bayi Reservoir, Hongqi Reservoir and Youth Reservoir. The water quality of the reservoirs keeps high standards all the year round.
The water regime of Panjin, its ability to control water regime and rational utilization of high-quality water sources provide water resources guarantee for the cultivation of high-quality rice in Panjin. Panjin belongs to temperate continental semi-humid monsoon climate. The climate is mild, with no heat in summer and no severe cold in winter, with an average annual temperature of 8.4℃. The four seasons are distinct, with the same season of rain and heat, and the frost-free period is 153- 195 days. The precipitation is moderate, with an average annual precipitation of 623.2 mm, mostly concentrated in summer, with an average summer precipitation of 392. 1 mm, accounting for 62.9% of the annual precipitation. The evaporation is 2.7 times larger than the precipitation, and the annual average evaporation is 1669.6 mm, and the air pressure changes in a single peak pattern, which changes with the seasons. The highest in June is 1 1.0 hectopascals, and the lowest in July is 1003.3 hectopascals. The wind direction is southwest wind in spring, summer and autumn, and west (east) north wind in winter. The annual average wind speed is 4.3m/s, the maximum wind speed is 5.8m/s in April, the minimum wind speed is 3.3m/s in August and the instantaneous maximum wind speed is 25.7m/s. ..
Judging from the climate zoning, only Panjin, Dalian, Yingkou and Jinzhou in Northeast China are located in the south temperate and semi-humid area. Panjin is located between 40 465 438+0' and 465 438+0 27' north latitude, with long and abundant sunshine in summer, with an average annual sunshine of 2768.5 hours. The annual total solar radiation is 65,438+030-65,438+040 kcal/cm2/year, which is higher than Dalian, Yingkou, Jinzhou and Northeast China. Rice in Panjin is harvested once a year, and the growth period is 158- 170 days. By the time of harvest, it was already frosted. At this time, the climate in Panjin is suitable, the air humidity alternates between dry and wet, and the temperature difference between day and night is large, which can make the organic matter in rice fruit more fully converted into sugar. This is an important reason why Panjin rice is of high quality and a little sweet. Panjin has embarked on the difficult road of introducing, improving, renewing, breeding and popularizing high-quality rice varieties since it planted rice. Especially after the 1960s, Panjin has made remarkable achievements in the breeding and popularization of high-quality rice. By 2007, the high-quality rice varieties Liao Yan 2, Yanfeng 47 and Yanfeng 49 independently cultivated by Panjin have been widely recognized by rice farmers.
Rice planting in Panjin started from low-lying land and artificial water lifting. After a hundred years, by 2007, all rice growers in Panjin had mastered the methods of water control, low-cost seedling raising, technical standards and methods of rice field management and rice growth management, fertilization standards and techniques, and ecological methods of weeding in rice fields, and were familiar with the "organic" rice planting methods. The production of high-quality rice in Panjin has entered the stage of standardization and refinement. Panjin rice is 100% improved single-season japonica rice. The large-scale planting of excellent rice varieties has been realized, and the Mi Yuan is stable, which is suitable for large-scale mechanized processing with advanced equipment.
By 2007, 63 grain enterprises in Panjin City had obtained the special protection mark of Panjin rice origin. There are 27 grain depots and 5 rice industries that realize the integration of storage, processing, packaging, transportation and marketing, and implement the whole-process quality control of production and circulation.
After the purchased rice is automatically weighed, it is dried with 30 tons/hour raw grain drying equipment. And then stored in a steel plate bin and a steel bar bin, cooled and ventilated, moisture is detected by a microcomputer, and the rice is fumigated circularly, so that the rice is not mildewed and does not suffer from insect pests. Use biological methods to control rodents in rice and rice storage areas.
Panjin grain enterprises adopt the most advanced rice processing production line in the world, and the daily processing capacity exceeds 100 tons. During the operation, there are more than 20 processes, such as removing impurities and stones, shelling and rough machining, whitening, water milling and whitening, and long and thick color selection. To ensure the high quality rate of Panjin rice.
Panjin rice packaging has obtained the patent of design, the packaging material is safe and environmentally friendly, the packaging style is mainly gifts, and the specifications are diversified. Panjin rice processing and packaging does not add any chemicals and additives, and the shelf life can reach 1 year, which ensures that the nutritional components of rice are not lost.
Panjin has convenient transportation. Qinhuangdao-Shenyang electrified railway and Gouhai railway run through it, with stations; Beijing-Shenyang Railway and National Highway 102 pass by, and the tangent point is the station; Beijing-Shenyang Expressway, Gouhai Expressway and National Highway 305 run through the whole territory, with entrances and exits and stations. Within a 3-hour drive, it covers airports and stations such as Dalian, Shenyang, Yingkou and Jinzhou. The large circulation of land, sea and air has created extremely convenient conditions for Panjin rice to be transported abroad.
Grain enterprises in Panjin fully guarantee the rapid batch transportation of Panjin rice through special roads and railways extending in all directions.