机构地区:[1]安徽农业大学资源与环境学院,安徽合肥230036 [2]中国科学院武汉植物园/中国科学院水生植物与流域生态重点实验室,湖北武汉430074
出 处:《生态环境学报》2012年第6期1024-1030,共7页Ecology and Environmental Sciences
基 金:国际植物营养研究所基金项目(IPNI-HB-34);国家科技支撑计划(2009BADA6B00);安徽省自主创新基金项目(11Z0101080)
摘 要:通过对砂浆黑土区小麦-大豆轮作制地不同施肥模式的杂草土壤种子库(0~15 cm)进行调查,分析种子库的大小、组成、多样性等特征,探讨施肥模式与群落演替速率之间的关系。结果表明,施肥模式显著影响着土壤种子库的大小、组成、多样性、群落演替速率。土壤样品中共检出杂草种子18种,隶属于11科,且各处理优势种组成差异明显。种子库密度按NPK>NP>NK>CK>PK顺序依次递减且差异极显著(P<0.01)。各处理物种组成不同,种数按CK>NPK>PK=NK>NP顺序依次递减,群落均匀度指数按NP>CK>NK>PK>NPK顺序依次递减且差异显著(P<0.05),物种多样性指数按CK>NP>NK>PK>NPK顺序依次递减,群落优势度指数按NPK>PK=NK>CK>NP顺序依次递减。我们初步认为适应与竞争机制影响土壤种子库的物种组成、密度的差异;施肥模式间土壤种子库的优势种变化尤为突出,引起均匀度的改变,导致施肥模式下土壤种子库多样性的差异。Whittaker指数按CK<NPK<PK=NK<NP顺序依次增大,表明土壤种子库的群落演替速率依次加快,说明长期平衡施肥模式(NPK)对土壤种子库群落的影响明显小于PK、NP、NK施肥处理,群落结构较PK、NP、NK施肥处理更稳定。气候、取样时间、除草剂等因素导致年际间、种植季间的杂草土壤种子库特征差异明显。本研究认为长期平衡施肥既有利于作物的优质高产,也有利于农田土壤种子库群落的稳定,是建立合理、高效、稳定的农业生态系统以及取得良好的经济效益和生态效益的重要施肥方式。The weed seedbank in the lime concretion black soil(0-15 cm) of a long-term fertilizer experiment was surveyed.We analyzed its density,species composition and biodiversity in relation to fertilization patterns and the rate of community succession under wheat-soybean rotation.The results showed the fertilization patterns significantly affected the density,species composition,biodiversity features and the rate of community succession of weeds.All the weed seeds affiliated with eighteen species and eleven families,and the dominant species differed remarkably from one treatment to another.The density of soil weed seedbank decreased significantly(P〈0.01) in a sequence of NPK〉NP〉NK〉CK〉PK.Due to the fertilizer treatment effects,the diversity of the weed seedbank species in the soil decreased in the following orders: CK〉NPK〉PK=NK〉NP for the species number,NP〉CK〉NK〉PK〉 NPK for the Pielou index,CK〉NP〉NK〉PK〉NPK for Shannon-Wiener index and NPK〉PK=NK〉CK〉NP for the Simpson index.Our preliminary results revealed that adaptation of and competition between different weed species may lead to the varied species composition and density,and changes in dominant weed species caused by different fertilizer treatments were particularly prominent.This resulted in more heterogeneity and biodiversity of weed seedbank in the soil.The increased sequence for the Whittaker index as CK〈NPK〈PK=NK〈NP demonstrated a speeding-up rate of community succession,implying that the long-term balanced fertilization(NPK) balanced fertilization had less effect on soil weed seedbank than the PK,NP or NK but yielded a more stable seedbank structure.The variation in soil weed seedbank species may be caused by changes in climate,sampling time,herbicide use,cropping seasons and years.The results suggested that the long-term balanced fertilization is very beneficial to producing high yield and quality of agricultural products and stabilizing the soil weed seedbank,and is also an important measure to create
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...