不同土地利用下黑土磷素肥力特征的研究

通过对海伦农田生态系统国家野外科学观测研究站内3种土地利用下共5个处理(裸地、草地、无肥耕地、施化肥耕地、施化肥和有机肥耕地)的典型黑土中的磷素进行了测定,结果表明经过20年长期定位试验后,3种土地利用方式下的土壤中草地全磷含量比裸地高17.5%,速效磷含量比裸地高22.9%;无肥耕地土壤全磷含量比裸地高7.9%,速效磷含量比裸地高80.1%。施化肥耕地全磷含量比无肥耕地高17.1%,速效磷含量是无肥耕地的3.3倍;施化肥和有机肥耕地全磷含量比施化肥耕地高46.3%,速效磷含量是施化肥耕地的3.3倍。土壤无机磷分级结果表明,不同土地利用下土壤中Ca2-P、Ca8-P、Al-P、Fe-P含量差异显著,而O-P、Ca10-P含量无明显变化,其中Ca2-P、Ca8-P、Al-P、Fe-P的含量,草地与裸地相比分别提高了30%、38%、17%、6.2%;无肥耕地与裸地相比提高了110%、75%、7.7%、-25%,与草地相比提高了62%、27%、-7.8%、-29%。施化肥耕地与无肥耕地相比,土壤中Ca2-P、Ca8-P、Al-P、Fe-P的含量分别提高了13%、153%、124%、92%;施化肥和有机肥耕地与施化肥耕地相比分别提高了341%、357%、136%、69%。对土壤磷的吸附性能测定结果表明,3种土地利用下土壤对磷的吸附能力为:无肥耕地>草地>裸地;耕地的3个处理中施化肥和有机肥可明显提高土壤对磷的吸附能力。

Rhosphorus Fertility Characteristics of Black Soil under Different Types of Land Use

The experiment was carried out to study the effects of land use on phosphorus characteristics correlatd with soil fertility of black soil in Hailun national field research station. The experiment concluded 3 types of land use and 5 treatments in all. The treatments were bald land (BL),grass land (GL),no fertilizers cultivate land (CK),applied chemical fertilizers cultivate land (NP) and applied chemical fertilizer and organic manure cultivated land (NPM). The P content of the soil was determined,the results showed that after 20 y long-term sited experiments,while no P fertilizer applied,compared with BL,the total P content of GL high 17.5%,the available P content of GL high 22.9%,and the total P content of CL high 7.9%,the available P content of CL high 80.1%. In the 3 treatments of CL,the total P content of NP was higher 17.1% than CK,and the available P of NP was 3.3 times to CK. The total P content of NPM higher 46.3% than NP,and the available P of NPM was 3.3 times to NP. Evaluation was made on the fractionation of soil inorganic phosphorus. The Results showed that the content of high-availability phosphorus components for plants (Ca2-P,Ca8-P,Al-P,Fe-P) was significant between different land uses,whereas the content of low-availability phosphorus components for plants (O-P,Ca10-P) was insignificant. While no P fertilizer applied,the Ca2-P,Ca8-P,Al-P,Fe-P content of GL were high 30%,38%,17% and 6.2% compard with BL respectively,CL was high 110%,75%,7.7%,-25% compard with BL and high 62%,27%,-7.8%,-29% compard with GL. In the 3 treatments of CL ,the Ca2-P,Ca8-P,Al-P,Fe-P contents of NP were high 13%,153%,124%,92% compared with CK,and NPM were high 341%,357%,136%,69% compard with NP. The methods of Moughli were adopted to evaluate the adsorption of inorganic phosphorus. The results showed that the adsorption capability of soil under different types of land use,was in the following order: CL(CK)>GL>BL,and applied organic manure can decrease the adsorption capability of soil obviously.