Changqing Land Resource Productivity, Production Potential And Farmland Yield Potential Evaluation Studies

China has a big population and a fast increase speed of it. Themutua1 relations axnong popu1ation, land a-nd grain have been in state ofintensity permanently. The fragi1e ecological environment has become theunfavorable factor to the development of agriculture, and as a result, thesoil degeneration phenomenon is paticularly serious now. Furthermore,the area of cultivated land has been decreasing ceaselessly during thecourse of industrialization and civilization. Therefore, it will be the majortask of China in 2l centUry to dispose the problem of population, land andfoodstuffThe land productivity evaluation and potential increase productioncalculation belong to studies on land resources quality and they form thepre-requisite and foundational means to resolve the conflicts betWeen manand land resources. Bllt restficted by the traditiona1 instruments andtechniques in our coUntry there are many insufficiencies in the study field,such as the renunciation from the agricultUral sustainable developmentobjects, the lack of studies on tiny tetritories, the disability of studyachievements to guide practices, and so forth.Concerned with the above insufficiencies, and illustrated with thecase of Changqing CoUnty Which is in Jinan City, this paPer attempts toimprove on the state of this research field. The staPle allemPts are asII!'fol1owsf @The attemPt to seek good methods that fit tiny territories onland productivity & potential productivity and cultivated land potentialincrease production researches. For this reason, closely combined with thepractical conditions of Changqing County various influencing factorswere synthetica1ly considered, scientific and logical eva1uation methodand calculating models were established. @Based on the calculation ofthe light-temPertae-water potentia1 productivity the 1and and socialpotential productivity were calculated additionally This can providebackers for the agricultUral sustainable development objects of ChangqingCounty. @From beginning to end of the research, remote sensing andgeograPhic information system techniques were utilized to improve thework efficiency and accuracy The factitious mistakes were avoided andthe computation outcomes were precis9ly eXPressed by grid maps consistof qlladrate units that a single one rePresents the reaI area of 900 squaremeters (30m x 30m). As the result, the research works'instrUctiona1effects on practices were assured and reinforced- @Thorough eXPlorationon scientific land utilization and preservation were carried out andmeasures that comPaible with the rea1ities of the research area werebrough forward.The main contents of the paPer are as fol1ows.(1)The method and target system of land productivity evaluation.From tWo main aspects, i.e., namral and society-economy-techniquefactors, land productivity were evaluated respectively Ten single naturalfactors were selected and evaluated according to their contributoryfunctions before they were synthetically eva1uated by calculating theirgeometrical average, which produced the natUal evaluaton index of landproductivity. Six single society--economy-technique factors were selectedand their weights were caIculated by means of AHP (Analytic HierarchyProcess). Then, by summing them up, the society-economy-tecboqueeva1uation index of land productivity was got. Finally, the synthetic indexof land productivity was calculated on the bases of the tWo indexmentioned above.(2)The land potential productivity.The methods of converse restrictive factor modifications and resourcesyllthetical equilibrium, accomPanied with GIS (geograPhic informationsystem) tools, were uti1ized to ca1culate land resources potential grainproductivity Photosynthesis, 1ight--temPeramre, l ight-te mp eramre -water,land and social potentia1 productivity were estimated step by step. ByIIImeans of rectifying light-temperature-water potential productivity with the natu...