Establishment of alien invasive plant, yellow sweet clover (Melilotus officinalis) at a complex ecosystem distributed with farmlands and wasted lands

Abstract

Abstract Alien invasive plants had a far-reaching impact on local vegetation and biodiversity, and the hazard of invasion was widely concerned. Field trial was conducted to discuss the establishment of yellow sweet clover and its interaction with local plant vegetation on a synthetical ecosystem patched with cultivated farmlands and wasted lands in northern China. The results showed the establishment for yellow sweet clover was quite different under the two land types. The density of seedlings in the wasted lands only reached up to 16.9% of that in the farmlands which flourished with annual large broad-leaf plants, like velvet weed (Abutilon theophrasti), jimson weed (Datura stramonium), and flower-of-an-hour (Hibiscus trionum) at a higher frequency contrast with thin-leaf species in the wasted lands, e.g. Salsola collina, Humulus scandens. The two types of lands had a community similarity (CJ = 0.5135), but both significantly decreased with the increasing density of yellow sweet clover. On details, biomass, plants per square meters, and diversity, they were all less or lower in wasted lands compared to farmlands. After its establishment, soil characteristics and soil texture were also modified due to yellow sweet clover itself or environmental factors, e.g. a higher level of available nitrogen and soil organic matter. The results suggested that it is not easy for yellow sweet clover to establish on wasted lands under the suppression of native plants and adverse environmental factors; but it may flourish in the farmlands with competitive advantages at initial stage, though presented a stagnation after generations.