Effects of invasion of Mikania micrantha on germination of rice seedlings, plant richness, chemical properties and respiration of soil

Abstract

Mikania micrantha, a creeper and climber, has invaded forests and agricultural areas in the Western Ghats. A quantification of the effect of Mikania on species richness and factors that contribute to its success would help to understand the invasion success of Mikania in the Western Ghats of India. This study investigated its impact on species richness and factors that contribute to its invasion success. Impact of Mikania on species richness was studied in areas invaded by Mikania and not yet invaded by Mikania by quadrat (1×1 m 2 ) method. Growth experiments were carried out with Mikania rhizosphere soil and soil treated with Mikania leaf leachate. Chemical characteristics such as electrical conductivity, organic matter, extractable P, total organic N and water-soluble phenolics, and microbial respiration of soil invaded by Mikania and not yet invaded by Mikania were measured. We observed lower species richness in areas invaded by Mikania compared to areas not yet invaded by Mikania. Seedling growth was suppressed in Mikania rhizosphere soil or soil treated with higher levels of Mikania leaf leachate. Higher levels of organic matter, total organic N and watersoluble phenolics, and lower microbial activity were observed in Mikania rhizosphere soil. Soil treated with Mikania leaf leachate has higher amounts of watersoluble phenolics. Mikania invasion appears to reduce plant species richness in the Western Ghats, and discourage seedling growth of certain plant species. Factors that are likely to contribute to Mikania success are its ability to pre-empt light and alter soil chemistry and biochemistry in ways that benefit the species.

Impact of Mikania micrantha H.B.K. Invasion on Diversity and Abundance of Plant Species of Chitwan National Park, Nepal

“…The second study area was very disturbed due to human as well as natural interferences (flooding) and higher disturbance degraded the habitat and made it unsuitable for many species and brought about the variation in species composition even in a small area. In addition the encroachment and increasing Mikania cover is the another reason for lower plant species diversity (Kaur et al 2012). This is also supported by the correlation analysis between invasion and species richness.…”

“…Many studies have already recorded that the alien invasion is harmful for the native species diversity (Kaur et al 2012). This study also found similar results for the invasive plant Mikania micrantha H.B.K.…”

Environmental Predictors of Indole Acetic Acid Producing Rhizobacteria at Fly Ash Dumps: Nature-Based Solution for Sustainable Restoration

“…The pH and electrical conductivity of soil/fly ash were determined in distilled water suspension (1:5 wt/vol), prepared by shaking for 1 h and filtering through Whatman filter paper #1, using digital pH meter (Mettler Toledo, Switzerland) and conductivity meter (Metrex Ltd., India) (Kaur et al, 2012). Contents of PO 4 -P and NO 3 -N were determined by molybdenum-blue method (Allen, 1989) and salicylate blue method (Anderson and Ingram, 1993), respectively.…”

Site‐specific management is crucial to managing Mikania micrantha

“…Unfortunately, applying the same control methods to every occurrence of a broadly adapted weed can be ineffective and costly (Bhagwat et al ., ). Mikania micrantha is an ideal example of the importance of applying diverse management approaches, as it is found in a broad range of habitats across its invaded range (Zhang et al ., ; Kaur et al ., ; Day et al ., ). Mikania micrantha is now found in 20 Pacific islands and territories (PICTs; Day & Winston, ) and most countries in south and south‐east Asia (Day et al ., ).…”