【作者】 张喜林；

【导师】 徐明岗； 魏丹；

【作者基本信息】 中国农业科学院 ， 农业资源利用， 2011， 硕士

【摘要】 在农田生态系统中,土壤动物一直是土壤生态过程不可缺少的组成部分,它承担着分解和养分矿化等作用。土壤线虫作为土壤中数量最多,种类最丰富的动物,它的生活进程和演化历史多样,取食类型千差万别,在生态系统中发挥着重要作用。土壤线虫数量巨大、形态各异、习性差别大、种类繁多、分布地域广泛,在土壤生物类群中占有极为重要的地位。黑土区是黑龙江省粮食主产区,黑土区农田土壤质量的好坏、肥力的高低对黑龙江省农业生产的影响非常大。研究土壤线虫群落分布、特征；长期施肥土壤生物肥力变化；探究影响黑土生物群落的环境因子,能够为保持和提高黑土肥力提供科学依据。利用1979年设立的黑土长期定位试验为研究平台,通过长期定位试验的方法,在作物生长期内分时期采集土壤样品,分离、鉴定土壤线虫的种类、数量,可以看出,土壤线虫种类繁多,数量巨大,初步鉴定出的线虫种类在10科、13属-16科、19属之间,随着作物生育期延长,土壤线虫种群数量有增加的趋势,在作物收获后期不同处理土壤线虫属的数量排序是：不施肥(18个属)>单施氮肥(15个属)>单施有机肥(14个属)>施氮磷钾肥(12个属)；不同土壤线虫种群中优势种群也不相同：植物寄生线虫的纽带科螺旋属线虫均为优势种群,食细菌线虫中的头叶科拟丽突属线虫均为优势种群。在土体剖面中,随着土壤深度增加,土壤线虫群落数量下降,种类减少。食真菌线虫群落主要分布在0～40cm土层；植物寄生线虫群落土要分布在0～60cm土层；食细菌线虫群落和捕食/杂食线虫群落主要分布在60cm以下。长期施肥土壤线虫总数下降,线虫种类增加,线虫多样性增加,线虫群落稳定性增强,丰富度增加。长期施用有机肥处理土壤线虫群落结构更加稳定,线虫种类丰富,其次为长期单施氮肥处理。长期施肥增加食细菌线虫相对丰度,降低植物寄生线虫相对丰度,施氮磷钾肥能够抑制植物寄生线虫生长,促进食细菌线虫发展。食细菌线虫相对丰度顺序是：施氮磷钾肥>单施氮肥>单施有机肥>不施肥；植物寄生线虫相对丰度顺序是：不施肥>单施氮肥>单施有机肥>施氮磷钾肥。土壤线虫群落中食细菌线虫的丰度均随着土壤有机质、全氮、全磷及速效磷含量的增加而增加,而不同施肥处理土壤线虫群落中植物寄生线虫的相对丰度则与土壤中有机质含量、全氮、全磷、速效磷及速效钾含量呈显著的负相关。更多还原

【Abstract】 In farmland ecosystems, soil animal has been soil ecological process indispensable constitutent part, it bears the decomposition and nutrient mineralization functions. Soil nematode in soil as the largest number, the most abundant species of animals, their life process and evolution history of diversity, feeding type differ in thousands ways, in ecological system, they play an mportant role. Soil nematodes are a huge number, their shapes and habits difference, various kind and distri-bute widely, they have very important position in groups of soil organisms.Black soil zone in heilongjiang province is a major grain producing areas,black soil is famous for its good soil quality and provide high cereal yield. We focus on the effects of nematode community on soil quality, the effects of long-term fertilization on the change of soil microbe. It is possible that we find the factors affecting mollisol microbial community and we take some measures to keep and improve soil fertility.The soils were sampled in long-term mollisol experiment station established in 1979 (Harbin, E126°35", N45°40"). The nematode species and numbers were detected by sampling, isolation and identification. The results show that the nematode species ranged from 10 familia and 13 genus to 16 familia and 19 genus. The nematode numbers increase followed the plant growth. At the stage of harvesting, the numbers of nematode genus in the order:CK (18 genus)> N application (15 genus)> organic manure (14 genus)> NPK application (12 genus). In addition, the nematodes show different response to the environment, e.g. soil bacterivorous nematodes respond sensitively to environment, however, soil fungivorous nematodes and omnivore/predator nematodes don’t respond sensitively to environment. Furthermore, the dominant species in nematode community show different abundance, e.g. helicotylenchus is the dominant species in plant-parasitic nematodes and acrobeloides nanus is the dominant species in bacterivorous nematodes. In soil profile, soil nematode numbers and species decrease along the depth. Fungivorous nematodes lived in the depth of 0 to 40 cm. Plant-parasitic nematodes distributed in the depth of 0 to 60 cm. Bacterivorous nematodees and omnivore/predator nematodes were found in the depth of less 60 cm. We found that soil nematode species and distributions correlated to soil moisture. In certain range, soil nematode numbers increase as the moisture increasing. Furthermore, the abundance of bacterivorous nematode increased as the increase of the concentration of soil organic matter, total nitrogen, total phosphorus and available phosphorus. Plant-parasitic nematodes decrease as the increase of the concentration of soil organic matter, total nitrogen, total phosphorus and available potassium.更多还原