Determination of Nutrient Cycling and Nutrient-use Efficiency in an Agroecosystem of Trifolium alexandrinum

In Egypt, Trifolium alexandrinum L. is an important green forage crop as well as an anti-diabetic medicinal plant. The overall forage phytomass was about 14.3 tons/fed/year. The current study assesses dry matter production, nutrient cycling and nutrient use efficiency (NTUE) in an agro ecosystem of T. alexandrinum under normal agricultural practices and rotational clipping by farmers. During the first and last three growth phases, the net above ground primary productivity was calculated to be around 0.066 and 0.093 g/g dry weight/day. Initially, the rate of nutrient accumulation in shoots was greater than the rate of biomass accumulation. There was a gradient of N and K concentration from roots to shoots, which is consistent with active translocation of these elements to the shoot. The amount translocated exceeds approximately 90% of the total N and K uptake. During the extensive growth period, the total organic constituents (TAC, CP, EE, and SOC) in the shoot reached their maximum content. Furthermore, T. alexandrinum was found to have different levels of NTUE during different growth periods. The primary controlling factor in changes in NTUE for the majority of elements was biomass allocation.