Impact of Long-Term Fertilization on Cropland Soil Fauna Community at Loess Soil, Shannxi, China

The relationship between long-term fertilization and cropland network for soil fertility and fertilizers in Loess soil of Shannxi soil fauna was studied at the station＇s experiment research Provincefrom Jul. 2001 to Oct. 2002. Six types of long-term fertilizer were carried out for this study including non-fertilizer （CK）, abandonment （ABAND）, nitrogenous and phosphors and potassium fertilizers combined （NPK）, straw and NPK （SNPK）, organic material and NPK （MNPK） and 1.5 times MNPK （1.5MNPK）. 72 soil samples were collected and 5 495 species of cropland soil fauna obtained by handsorting and Cobb methods at 4 times, belonging to 6 Phyla, 11 Classes, 22 Orders, 2 Superfamilies, 61 Families and 35 Genera. The result showed that different fertilizer had significantly impacted on the cropland soil fauna （F = 2.24, P〈0.007）. The number of the cropland soil fauna was related to the soil physicochemical properties caused by long-term fertilization. The result by principal component analysis, focusing on the number of 15 key soil fauna species group＇s diversity, evenness of community and the total soil fauna individuals indicated that the effects of SNPK, NPK, MNPK and 1.5MNPK were significantly different from that of the cropland soil fauna, in which, SNPK and NPK had the positive effect on cropland soil fauna, and MNPK and 1.5 MNPK had the negative affect, others could not be explained. By principal component I, the synthetic effect of different fertilization on the total soil fauna individuals and the group was most significant, and the effect was little on evenness and diversity. By value of eigenvectors, the maximum one was 9.6248, and the minimum one was - 1.0904, that means the 6 types of fertilization did not affect evenly the cropland soil fauna.

Recent Advances in Research on Soil Microbial Community Diversity under Conservation Tillage

The influencing factors of soil microbial community under conservation tillage system were summarized,the changes of soil microbial community under conservation tillage system and the general situation of soil microbial community research under rotation system were analyzed,and the contents of soil microbial community need to be future studied were prospected.

土壤动物群落多样性对3种种植模式的响应研究

为合理筛选适宜种植模式,维持农业的可持续发展提供参考。采用手捡法和改进的Tullgren干漏斗法,研究休闲轮作(FRCs)、稻菜轮作(RVCs)、蔬菜连作(VCCs)3种种植模式下,土壤动物群落组成及多样性。结果表明,3个处理样点共获得各类土壤动物526只,经鉴定有3门9纲14目。与VCCs、FRCs处理相比,RVCs处理条件下引发了一些类群的发生与消长,造成了部分类群的缺失,形成了不同的优势类群。土壤动物数量0～15cm土层均多于15～30cm土层,分别较15～30cm土层多出15.7%、86.6%和110.0%。RVCs处理Shannon-Weiner指数(H)、Pielou均匀性指数(E)、Simpson优势度指数(C)均为最大,且0～15cm土层高于15～30cm土层。土壤动物类群的相似性综合分析表明,VCCs处理与FRCs处理类群的相似性系数较高,与RVCs处理类群的相似性系数较小。

喀斯特地貌不同农作物下土壤动物群落结构与组成

2013年7月分别对位于喀斯特地区的广西壮族自治区河池市宜州区境内的葡萄、板栗、玉米、柑橘、柚子、桑树、水稻、香蕉、松树、甘蔗10种农作物下20个样地的土壤动物多样性进行调查。结果表明:20个样地共获土壤动物2861只,隶属3门8纲14目,共18个类群,其中优势类群为弹尾目和蜱螨目,占比为89.97%;常见类群为膜翅目、线蚓科、单向蚓目、鞘翅目、双翅目5类,占比为8.52%。对喀斯特地貌不同农作物下土壤动物群落多样性研究表明,在垂直分布上,土壤动物类群数和个体数均呈现出表聚现象,在水平分布上的差异与人类的干扰程度息息相关。