Their countermeasures include reforming the fiscal and taxation system leaning to cities and adjusting national policy of profit distribution ; improving and innovating the rural financial system and broadening the channels for agricultural investing and financing ; reforming the rural land system and advancing the marketization of lands 实现农民收入较快增长的制度对策是:改革城市偏向的财税体制,调整国家利益分配政策;改革完善农村金融体制,拓宽农业投融资渠道;改革农村土地制度,促进土地的市场化。
Four mechanisms of sperm competition ( sperm stratification , sperm incapacitation , sperm removal and sperm flushing ) , four impact factors on paternity ( mating order , number of mated males , mating intervals and cryptic female choice ) and three kinds of male ' s adaptation mechanisms of sperm competition ( morphological adaptations , physiological adaptations and behavioral adaptations ) are reviewed 阐述了精子竞争的概念,综述了精子层化、精子失能、精子移除和精子冲洗4种昆虫精子竞争的机制以及雄性在形态、生理和行为上3类避免精子竞争的机制,详细讨论了交配次序、交配雄性数量、交配间隔以及隐秘雌性选择4个影响父权偏向的因素。