不同土地利用方式对山东丘陵农田杂草群落结构与动态的影响

摘要

In order to clarify the effects of different land use patterns on farmland ecosystem in hilly regions,the experiment was carried out in spring of 2015 in Linqu County,Shandong Province.Two traditional land use patterns (wheat and millet fields) and three novel land use patterns (vegetable fields,peach orchards and abandoned lands) were selected as experimental objects.The soil nutrients,weed community structure and biodiversity were investigated and analyzed under the five land use patterns.The results indicated that the vegetable fields and peach orchards had obviously higher soil organic carbon (SOC),total nitrogen (TN) and total phosphorus contents compared with the abandoned lands,wheat fields and millet fields.The soil available phosphorus (AP) and electric conductance (EC) of vegetable fields were significantly higher compared with the other land use patterns.The similarity coefficient of weed communities under the 5 land use patterns was 0.05 ～0.46.The species richness(SR) of abandoned lands was the highest (9.83),while that of vegetable fields was the lowest (3.33).The DA functional group reigned supreme in wheat fields,and the MA functional group reigned supreme in abandoned lands.The millet fields and peach orchards had relatively even distribution of weed functional groups,and the former was dominated by the MA and DP functional groups while the latter was dominated by the MA and DP functional groups.The abandoned lands and millet fields had higher plant diversity with the diversity indexes as 1.74 and 1.73 respectively,and the diversity index of peach fields,wheat fields and vegetable fields decreased in turn.%为了探明不同土地利用方式对丘陵地区农田生态系统的影响,本研究于2015年春季在山东省临朐县(丘陵山区)选择传统耕作方式的麦地和谷子地、近10 ～ 20年因种植结构调整而呈现的菜地、果园及撂荒地为对象,系统分析该5种土地利用方式下农田生态系统中土壤养分、杂草群落结构及多样性变化状况.结果表明:土壤理化性质,菜地、桃园中土壤总有机碳(SOC)、全氮(TN)和全磷(TP)含量明显高于撂荒地、小麦地和谷子地;菜地土壤中有效磷(AP)和电导率(EC)显著高于其它4种土地利用方式.杂草群落结构:5种土地利用方式下杂草群落的相似系数为0.05 ～ 0.46;撂荒地的杂草丰富度最高(9.83),菜地最低(3.33);小麦地DA杂草功能群占绝对优势,撂荒地MA杂草种群占绝对优势.谷子地和桃园中杂草功能群分布较为均衡,前者以MA和DP两种功能群为主,后者以MA和MP两种功能群为主.植物多样性:撂荒地和谷子地高,分别达1.74和1.73,桃园、小麦地和菜地依次递减.