Farmland Productivity And Grain Production Potential In The Typical Agricultural Areas In Northern Lesser Xing’an Mountain

Arable land, the material basis of a country, which play an important role in economic development and social stability. The quantity, quality and ecological security of the arable land must be directly affect the food production and supply. Food security and ecological environment were greatly attached and wide attention by the state and society. Presently, develop ecological and sustainable agriculture, change the mode of agricultural production improving the comprehensive production capacity of arable land has become very important to the food security. Heilongjiang province, the major grain producing areas of China, plays an important role in the national food security. There are many advantages of grain production in Heilongjiang, including the agricultural acreage, soil conditions, mechanization and the merchandise rate of grain. However, the typical regions in the northern Lesser Xing’an Mountains fall behind in their grain production due to climate conditions, topography, infrastructure and the production technology. Therefore, carrying out the farmland productivity and production potential analysis, revealing the soil nutrient status, characteristics, change rule and the grain production potential are very important in this region. These results must be of important strategic significance for planting structure adjustment, scientific management of agricultural production, stable growth of grain and food security.In the present study, combining with the Heilongjiang province farmland productivity evaluation project, samples of the typical agricultural regions in northern Lesser Xing’an Mountains were collected and investigated. The cultivated land resource properties and spatial database were established by using Geostatistics, Geographical Information System (GIS), Fuzzy Mathematic Theory, Delphi Method and Analytic Hierarchy Process to clarify the soil fertility changes during the past thirty years since the second soil census. The results showed that, compared with the values from the second national soil survey, the average content of soil organic matter, total nitrogen, and available potassium had reduced by 41.7%,28.7%, and 40.7%, respectively. The average content of available phosphorus reached a high value of 23.7 mg/kg, increases by 64.6%. The average pH value was 5.51, which represent a tendency of acidification. The cultivated land of the investigated area were divided into five grades by using cumulative curve method. The area of the first grade land was 26,842 hm2 takes up 8% of the total territory, the second grade was 77375.13 hm2 takes up 23.2%, the third grade land reach to 102343.5 hm2 accounting for 30.6% was the biggest one, the fourth grade land was 84168.49 hm2 takes up 25.2% and the fifth class land was 43321.3 hm2 takes up 13%. These results elucidated the soil fertility grade and soil type distribution characteristics that provide guidance for cultivated land utilization of pertinence and planting industry structure adjustment. Integrated fertility index (IFI) was employed to predict and. classify the farmland production potential. The high- and middle high production areas contributed 42.5% of the total GPP with only 31.2% of the total land area, while the middle-to low production areas made up the rest 57.5% of the total GPP in virtue of a relatively larger land area proportion of 68.8%. Because of the climate, topography and other factors, the agricultural production of the Lesser Xing’an Mountains area was comparatively lagging behind. Consequently, strengthen attention to this region, middle-low yielding farmland remaking and farmland infrastructure construction to improve the region become a grain production potential area.Results of the current studies showed a great change of the soil physical and chemical properties and nutrient supply imbalance in the northern Lesser Xing’an Mountains due to the extensive production in past three decades. Accordingly, strengthen the agricultural ecosystem structure and functional adjustment to improving the use efficiency and enhancing the production potential of the cultivated land in the northern Lesser Xing’an is particularly important.