Study On Phosphorus Fractions Of Different Aggregates In Brown Desert Soil

Phosphorus is one of the essential microelements for plant，and it has a great influence inboth growing development and volume of productions of crops. Because the disadvantageousnatural conditions such as droughts，sandstorms and salt and alkali，so as the undesirable irrigationand tillage method in Xinjiang，which makes soil granular structure hard to take shape. And at thesame time，they are inevitably suffering a great destruction. Therefore，my research about formsand distribution characteristics of fractions of different particle inorganic phosphorus and organicphosphorus in different cultivated age gray-brown desert soil and different particle has not onlythe function to expose the degradation mechanism of soil itself but also to provide sometheoretical and practical references about the rational utilization，improvement and fertilize maincultivated soil in Xinjiang. Research results are as follows:1. Studying regularities of distribution of different inorganic phosphorus fractions of aggregatesin brown desert soil that has10-14years cultivated age in three counties in south Xinjiang.Research result: Inorganic phosphorus aggregates decreasing with increasing particle size inbrown desert that has10-14years cultivated age in three counties in south Xinjiang. But the rangeof variation of inorganic phosphorus is different due to the different land use patterns. Ca10-P givespriority to different inorganic phosphorus fractions; it occupies22%~55%of total quantity ofinorganic phosphorus. Phosphorus.Fe-P and Al-P have the lowest rate in inorganic phosphorus，which accounts for from2%~6%of the total. The O-P accounts for from9%~30%and theavailable phosphorus Ca2-P covers5%. Ca8-P is20%~30%. The contents of different aggregates ofinorganic phosphorus vary greatly. Ca10-P is a dominant composition among the total inorganicphosphorus in brown desert soil that has10-14years cultivated age in the three counties of SouthXinjiang，accounting for about half percentage. The difference of inorganic phosphorus fractionsbetween different aggregates reaches extremely significant level (P <0.01).2. Studying regularities of distribution of different organic phosphorus fractions of aggregates in desert soil that has10-14years cultivated age in three counties in south Xinjiang. Organicphosphorus aggregates decreasing with increasing particle size in brown desert that has10-14years cultivated age in three counties in south Xinjiang. And it presents in an order that highstability organic phosphorus> activity organic phosphorus> medium activity organic phosphorus> medium stability organic phosphorus. But the range of variation of organic phosphorus isdifferent due to the different land use patterns. High stability organic phosphorus is a dominantcomposition among the total organic phosphorus in brown desert soil that has10-14yearscultivated age in the three counties of South Xinjiang，accounting for over half percentage. Thedifference of organic phosphorus fractions between different aggregates reached significant level(P <0.05).3. Studying regularities of distributions and content of different inorganic and organicphosphorus fractions of aggregates in brown desert soil that has different cultivated age in threecounties in south Xinjiang. The distribution of each forms of inorganic and organic phosphorus inaggregates has some differences because of the different usage of land. The contents of all formsof inorganic phosphorus have a trend of decreasing with the increasing size of particle diameter.And these differences of organic and inorganic phosphorus fractions in different aggregates reachsignificant level (P <0.05). It has an obvious diversity about the content of inorganic phosphorusin different cultivated age desert soil in three counties in south Xinjiang. The content of inorganicphosphorus in chart A is more than chart B in different particle soil. In chart A and B，the order ofcontribution rate of different forms of inorganic phosphorus that grain diameter is<0.1mm、0.25~1mm、1~3mm、>3mm is Ca10-P> Ca8-P> O-P> Ca2-P> Al-P> Fe-P. In chart A, the orderof contribution rate of different forms of inorganic phosphorus that grain diameter is0.1~0.25mmis Ca10-P> Ca8-P> O-P> Ca2-P> Al-P> Fe-P. In chart B, the order is Ca10-P> Ca8-P> O-P>Ca2-P> Fe-P> Al-P. The distribution of each forms of organic phosphorus in aggregates has somedifferences because of the different usage of land. The contents of all forms of organic phosphorushave a trend of decreasing with the increasing size of particle diameter. It has an obvious diversityabout the content of organic phosphorus in different cultivated age brown desert soil in three counties in south Xinjiang. The content of organic phosphorus in chart A is more than chart B indifferent particle soil. In chart A and B，the order of contribution rate of different forms of organicphosphorus that grain diameter is <0.1mm is high stability organic phosphorus> medium activityorganic phosphorus> activity organic phosphorus> medium stability organic phosphorus. In chartA, the order of contribution rate of different forms of inorganic phosphorus that grain diameter is0.1~0.25mm,0.25~1mm,1~3mm and over3mm is high stability organic phosphorus> activityorganic phosphorus>medium activity organic phosphorus> medium stability organic phosphorus.In chart A, the order of contribution rate of different forms of inorganic phosphorus that graindiameter is0.1~0.25mm，0.25~1mm，1~3mm and over3mm is high stability organic phosphorus> activity organic phosphorus> medium stability organic phosphorus> medium activity organicphosphorus. The content of organic P more than the previous research results that this study of theresultes, this due to blindly use of phosphate fertilizer the local people.4. Under the different pattern use of lands，the content of basic physicochemical property inbrown desert soil that has10-14years cultivated age is more than the brown desert soil that over70years cultivated age. The distribution of particle organic matter， which grain size is<0.1mm、0.25~1mm,1~3mm,>3mm alkali-hydrolyze nitrogen, total phosphorus, rapid availablephosphorus, total potassium, rapid available potassium, Ph value, total salt volume in aggregateshave some differences in the three counties in south Xinjiang. And these differences in the threecounties reach significant level (P <0.05). In chart A,B, alkali-hydrolyze nitrogen, rapid availablephosphorus, rapid available phosphorus the order of contribution rate of different that countyShaya>county Kucha>county Awat of different aggregates in the three counties in south Xinjiang.The content of soil organic matter, alkali-hydrolyze nitrogen, total phosphorus, rapid availablephosphorus, total potassium, rapid available potassium decreasing with the increasing of size ofparticle diameter, while the distribution differences of soil pH value, total salt volume in each kindof particle diameter is not obvious.