Nutrients (N, P and K) dynamics associated with the leaf litter of two agroforestry tree species of Bangladesh

Abstract

© iForest -Biogeosciences and Forestry IntroductionChemical fertilizer is now commonly used in agricultural practices, but it becomes ex pensive and farmers are reducing its use due to negative environmental impacts (Good et al. 2004). In addition, access to fertilizer in developing nations is limited (Sanchez 2002). It is an important task to gain a better understanding how agricultural practices can be designed with low input of fertilizer. Maintenance of soil productivity is a critical issue in a tropical agroecosystems. Agro forestry practice is an important component of it. Tropical farmers use this practice for their dependence on organic residues as low cost and readily available nutrients for soil fertility management (Nair 1989, Kwabiah et al. 2001. To this regard, agroforestry got special impetus in tropical agriculture.Farmers of the tropical region traditionally use variety of species composition in agro forestry practices. In Bangladesh, legumi nous tree species are traditionally used in different agroforestry practices. Presently, farmers prefer Eucalyptus camaldulensis and Swietenia macrophylla due to their commer cial values. Agroforestry being a people ori ented program, farmer's preference should be acknowledged, but the performance of these species is needed to be scientifically assessed with due attention in terms of nutri ent return efficiency for further promotion. However, nutrient return from a tree is influ enced by quantity, quality (nutrient composi tion) and rate of leaching and decomposition of plant litter (Senevirante et al. 1998, Kwa biah et al. 2001. Leaf litter is the main and quick source of nutrient return to the soil compared to other litter components (Tukey 1970, Wetzel & Manny 1972, Mason 1977, Dahm 1981, Park & Hyun 2003. The present study aimed to assess the pattern of nutrients leaching (N, P and K) from the leaf litter of E. camaldulensis and S. macro phylla in laboratory condition. Materials and Methods Leaf litter selection and leaching exper imentBulk of yellowish senescent leaves of E. camaldulensis and S. macrophylla were col lected during March 2007 (maximum leaf fall period). This period corresponds to dry season and no leaching was occurred from litter. Litter was air-dried at room tempera ture for one week. For each species, air-dried leaves were thoroughly mixed and weighted to two grams as an individual sample and thus a total of 42 samples were prepared. Each sample was placed at room temperature into individual beaker (500 ml) and 250 ml of distilled water was poured to each beaker and few drops of HgCl2 solution (50 mg l -1 - McLachlan 1971, Otsuki & Wetzel 1974 were added in each beaker to prevent fungal decay. Five samples were kept into an oven at 80°C until constant weight to get the airdry to oven-dry conversion weight. Sample collection and measurementsThree replicates of samples were collected at 0, 1, 2, 3, 4, 8, 12, 24, 36, 48, 72 and 96 hours of intervals and the collected samples were ringed by distilled water and ovendried at 80°C to const...

Soil nutrient status, nutrient return and retranslocation in poplar species and clones in northern Iran

“…Similar to our results, Singh et al (1989) and Lodhiyal & Lodhiyal (1997) reported the returned nutrient content by leaf litter in the order of N>K>P in Populus deltoides plantations in moist plain area in the north of India. However, Mahmood et al (2009Mahmood et al ( , 2011 reported nutrient release from leaf litter of three tree species in Bangladesh follows the order of K>N>P.…”

Leaf Litter Decomposition and Nutrient Dynamics Associated with Common Horticultural Cropland Agroforest Tree Species of Bangladesh

“…The variation in nutrients (N, P, and K) concentration in the leaf litter of the studied species at the initial stages of decomposition was found (Figures 3, 4, and 5) as the selected tree species were from different families having variation in chemical and biochemical properties of leaf litter [43][44][45]. Comparatively higher initial concentration of N, P, and K concentration in the leaf litter of Z. jujuba indicated that capabilities of this species to retranslocate these nutrients were lower during the senescence of leaves [6,46,47].…”

Effect of plant species on P cycle-related microorganisms associated with litter decomposition and P soil availability: implications for agroforestry management

“…In contrast, the PSM activity was favored at the preserved site. According to previous reports (Mahmood et al 2009), E. camaldulensis ensured the supply of phosphorous to the agroforestry system by favoring AMF and PSF activities, as determined by the AMF root colonization and the phosphatase activity, respectively. Finally, these microbial populations may be indicators of soil quality useful in assessing the effectiveness of land restoration in semiarid environments.…”

“…It is known that E. camaldulensis litter has a faster decomposition rate (Mahmood et al 2009). In this study, the Eucalyptus litter at the experimental site decomposed faster than the mixture, whereas the P. reticulata litter alone showed the slowest decay, which is likely due to the low lignin content of the former and the high lignin content of the latter.…”

“…Therefore, tree-based agroforestry systems, particularly those including Eucalyptus species, show an efficient return of soil nutrients (Mahmood et al 2009, Pagano et al 2008) that greatly contributes to the maintenance of soil fertility.…”