Effect of Phragmites japonicus harvest frequency and timing on dry matter yield and nutritive value

Control of runner reed (Phragmites japonicus) in lentic wetlands

“…However, those lentic wetlands with relatively monotonous topography and landscape are likely to be occupied by strong competitors such as P. japonicus which may result in eventually diminished biodiversity of wetland ecosystems. To conserve abandoned paddy fields as valuable lentic wetlands for wildlife from monotypic occupation by P. japonicus, we recommend the methods of treatment as follows: (1) regular removal of aboveground shoots including aerial stolons by hand-clipping at growing season (Tanaka et al 2017), (2) mechanical excavation of mature stands when the great part of the wetland is already occupied since mature stands do not make stolons, which are essential for P. japonicus to expand (Hong et al 2012), and (3) subsequent planting using alternative vegetational unit such as S. mucronata. In our study, the planting after the excavation could interrupt P. japonicus to occupy and support the target species such as N. pygmaea to thrive particularly in abandoned paddy fields (Kim et al 2010).…”

Phytoremediation Using Aquatic Plants

“…Coinciding with the decrease in nutrient concentrations in above-ground biomass, belowground concentrations of N and P increase, representing the preparation for plant senescence with nutrient storage in the roots and rhizomes for the following season's growth (Garver et al, 1988). Meuleman et al (2002) suggested that harvesting during the winter meant that only 9% of N and 6% of P associated with nutrient loading was removed, whereas, harvesting above-ground parts during peak nutrient storage in summer enhanced removal to 40-50% of N and P. Seasonality is important,although seasonal effects will differ between temperate, subtropical and tropical zones with macrophytes in the latter two zones showing less element translocation and therefore enabling multiple annual harvests (Vymazal, 2007).Macrophytes may perform poorly if nutrient translocation to the rhizome is inhibited by harvesting during the active growing period (Tanaka et al, 2017), although the issue of nutrient allocation is less problematic for floating macrophytes and emergent macrophytes deployed in FTWs as the full plant can then be harvested (Wang et al 2014).…”

“…However, different options need to be considered in pre-treatment, such as de-wetting and briquetting,since fresh plant biomass comprises up to 90% water (Newete and Byrne, 2016).Macrophyte biomass may also be used for animal feed, or to make compost or biochar (Quilliam et al, 2015;Tanaka et al 2017). Quilliam et al (2015) discussed in detail the issues with these PBRSs in terms of the transfer of pathogens, bio-magnification of heavy metals and propagation of invasive species.…”

Nutrient Remediation Efficiency of the Sedge Plant (Cyperus alopecuroides Rottb.) to Restore Eutrophic Freshwater Ecosystems

“…Land desertification and population growth have recently raised demand for highquality fodder products [21]. Whereas, the forage production system faces numerous challenges, including as a rival with the production of food crops and agricultural area reduction [22].…”