植物篱-农作坡地土壤团聚体组成和稳定性特征

基于植物篱控制水土流失的长期定位试验，研究植物篱-农作坡地土壤团聚体组成和稳定性特征.结果表明： 与常规等高农作模式相比，植物篱-农作复合农业模式下土壤>0.25 mm机械稳定性和水稳性团聚体含量分别显著增加13.3%~16.1%和37.8%~55.6%，明显提高了各坡位粒级>0.25 mm土壤水稳性团聚体含量，改善了粒级>0.25 mm土壤水稳性团聚体在下坡位的相对富集和上坡位相对贫乏的状况.植物篱显著提高了土壤团聚体平均质量直径和几何平均直径，降低了土壤团聚体分形维数和>0.25 mm土壤团聚体破坏率，进而增强了土壤团聚体的稳定性和抗蚀性.坡度与植物篱类型对土壤团聚体组成、稳定性和坡面变化无显著影响.

Effects of decabromodiphenyl ether(BDE-209) on the antioxidant enzyme activities of Lutjanus argentimaculatus mantle membrane

Based on a long-term experiment of using hedgerow to control soil and water loss, this paper studied the composition and stability of soil aggregates in a hedgerow-crop slope land. Compared with those under routine contour cropping, the contents of >0.25 mm soil mechanical-stable and water-stable aggregates under the complex mode hedgerow crop increased significantly by 13.3%-16.1% and 37.8%-55.6%, respectively. Under the complex mode, the contents of >0.25 mm soil water-stable aggregates on each slope position increased obviously, and the status of >0.25 mm soil wate-stable aggregates being relatively rich at low slope and poor at top slope was improved. Planting hedgerow could significantly increase the mean mass diameter and geometric mean diameter of soil aggregates, decrease the fractal dimension of soil aggregates and the destruction rate of >0.25 mm soil aggregates, and thus, increase the stability and erosion-resistance of soil aggregates in slope cropland. No significant effects of slope and hedgerow types were observed on the composition, stability and distribution of soil aggregates.