The Basic Soil Productivity Change Under Long-term Fertilizations In Winter Wheat And Summer Maize Cropping System In Fluvo-aquic Soil Area

The BSP （basic soil productivity） change has important significance to increase crop yield, facingnational increasing food demand, strengthening BSP cultivation and digging farmland productionpotential has been a problem needs to be explored and solved urgently, so the research and analysis ofthe evolution law and influencing factors on BSP under high strength use of farmland in China hasimportant theoretical and practical significance to satisfy increasing food demands in China by guidingBSP cultivation in major grain producing areas. Because of the past researches are mostly based on thecontinuous no fertilizer treatment, the results can not reflect the real evolution law of BSP. In this essay,the BSP yields, photo-temperature productivity and photo-temperate-precipitation productivity of winterwheat at the long-term locating site in Henan Province was simulated by DSSAT model, to study theevolution law of BSP during1991-2008a, and clear the influence factors on it, then analysis theascension space of BSP in fluvo-aquatic soil. At the same time, the thespatial-temporal evolution law ofBSP under conventional fertilization during1987-2006a in9provinces （cities） over the fluvo-aquic soilarea was studied by basic soil productivity index （BSPI） method. The main results are summarized asfollows:（1） The effect of long-term different fertilizations on BSP yields in fluvo-aquic soil: After18years’fertilization management, the BSP yields of NPK, NPKM,1.5NPKM and NPKS treatments were allincreased in a certain degree in winter wheat and summer maize seasons. In general, organic manure orstraw with fertilizer can more effectively increase BSP than single fertilizer;1.5NPKM treatment is thebest way to cultivate basic soil productivity in fluvo-aquatic soil.（2） The effect of long-term different fertilizations on contribution rate of BSP to yields influvo-aquic soil: The95%confidence interval of contribution rate of BSP to yields ranged from41.1%to62.0%in winter wheat season, the size order of the annual contribution rate of BSP to yields of NPK,NPKM,1.5NPKM and NPKS treatments was NPKM>1.5NPKM> NPKS> NPK, Organic manure orstraw with fertilizer can more effectively increase contribution rate of BSP to yields than singlefertilizer. The95%confidence interval of contribution rate of BSP to yields ranged from51.8%to75.2%in summer maize season, the size order of the annual contribution rate of BSP to yields was1.5NPKM> NPKS> NPK> NPKM.（3） The effect of soil nutrient on BSP in fluvo-aquic soil: Soil organic carbon and total nitrogencontents had the highest correlation with contribution rates of BSP to yields, the values of R²reached0.5809,0.5122, respectively （n=68）, that indicated soil organic carbon and total nitrogen contents werethe main influencing factors on contribution rates of BSP to yields in winter wheat season in fluvo-aquicsoil. Soil total phosphorus and available phosphorus contents had the highest correlation withcontribution rates of BSP to yields, the values of R²reached0.5442,0.4352, respectively （n=68）, thatindicated total phosphorus and available phosphorus contents were the main influencing factors oncontribution rates of BSP to yields in summer maize season in fluvo-aquic soil. （4） The temporal evolution law of BSPI （basic soil productivity index） under the conventionalfertilization in fluvo-aquatic soil area: BSPI of winter wheat and summer maize had a significant rising trendduring1987-1997; BSPI was not obvious changeable during1997-2006; The BSPI after1997was higher thanthe years before1997.（5） The spatial evolution law of BSPI under the conventional fertilization in fluvo-aquatic soil area：BSPI in different latitudes had obvious differences, the low latitude zone （34°15′-35°19′） had thehighest BSPI in both winter wheat and summer maize season. BSPI in different provinces influvo-aquatic soil area also had significant difference, Jiangsu province had the highest BSP in bothwinter wheat and summer maize season.（6） The analysis of crop potential productivity and ascension space of BSP in fluvo-aquatic soil：After18years’ fertilization management, the ascension spaces of BSP in winter wheat season weremore than5100kg·hm^-2, the ascension degrees ranged from53.1%to66.6%; the ascension spaces ofBSP in summer maize season were more than3800kg·hm^-2, the ascension degrees ranged from43.7%...