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Litter production and decomposition dynamics of a rare and endemic bamboo species Munrochloa ritcheyi of Western Ghats, India
Abstract
The present study examined the litter production, decomposition and nutrient release dynamics of Munrochloa ritcheyi, a rare and endemic bamboo species of Western Ghats. The litter production and decomposition were studied using the standard litter trap and bag techniques. The total annual litter production was 2.842 t ha(-1) year(-1). Litter production followed a triphasic pattern with a major peak in February 2012 and two minor peaks in May and December, 2011. The rate of decomposition in M. ritcheyi was a good fit to exponential decay model suggested by Olson (1963). The decomposition rate constant of M. ritcheyi was 0.009 day(-1) and the half-life was 77 days. The decrease in the N and K content of the decomposing litter was continuous whereas P, Ca and Mg showed temporary accumulation phases before final release. The release of nutrients from the decomposing litter was in the order N = Mg > K = Ca > P.
... The leaf litter of T. undulata had a higher initial N concentration and a C:N ratio below 20, which were likely reason for the faster mineralisation, and the situation was vice versa in H. binata. The decline in N concentration in later stages of decomposition was likely due to high N demand from the microorganisms (Kaushal et al. 2012) and loss of easily leachable components from leaf litter (Upadhyaya et al. 2012;Thomas et al. 2016). The initial decrease in the P concentration was attributed to the rainy season that encouraged the leaching process and leaching has been reported to escalate the release of P (Zaharah and Bah 1999;Kaushal et al. 2012). ...
... The immobilisation of P during initial stages of decomposition was also observed in earlier studies (Adams and Angradi 1996;Yadav et al. 2008). In case of K, like in this study, many other studies have also reported a rapid initial release (Swarnalatha and Vikram 2011;Thomas et al. 2016). K is prone to physical leaching as it is not structurally bound in organic compounds and K has high potential solubility (Kaushal et al. 2012;Bargali et al. 2015;Thomas et al. 2016). ...
... In case of K, like in this study, many other studies have also reported a rapid initial release (Swarnalatha and Vikram 2011;Thomas et al. 2016). K is prone to physical leaching as it is not structurally bound in organic compounds and K has high potential solubility (Kaushal et al. 2012;Bargali et al. 2015;Thomas et al. 2016). ...
Litterfall production, decomposition and nutrient release was investigated for three prominent agroforestry tree species, Prosopis cineraria, Tecomella undulata and Hardwickia binata, grown in the arid western region of India. The highest litterfall was recorded for H. binata (9.44 Mg ha−l y⁻¹) followed by P. cineraria (8.94 Mg ha−l y⁻¹) and T. undulata (3.74 Mg ha−l y⁻¹). It took 15, 12 and 9 months for decomposition of 90% of the litter of H. binata, P. cineraria and T. undulata, respectively. Regression analysis showed that rainfall and air temperature had significant impacts on the decomposition process. Soil moisture and soil microbial biomass carbon showed high correlations (R² > 0.70, p < 0.01) with litter decay. The rate of release of N (kN = 0.0014, surface (0–15 cm); kN = 0.0015, sub-surface (15–30 cm)) and K (kK = 0.0041, surface; kK = 0.0047, sub-surface) was highest from P. cineraria, whereas release rates of P were statistically equivalent for all species. N release from the decomposing litter increased initially, but then decreased as decomposition progressed. Concentrations of P, K and Mg in the litter decreased throughout the decomposition, with some fluctuations in P and Mg for P. cineraria and H. binata at the later stage. Ca release did not follow any specific trend. P. cineraria, with considerable amounts of litterfall, the highest nutrient inputs to the soil and the most rapid release of nutrients during the decomposition, was concluded to facilitate greater fertility build-up of the soil compared with the other two species.
... Según Kuruvilla et al., (2016), la investigación sobre la descomposición de la hojarasca es útil para determinar la cantidad de nutrientes que pasan de sul-reservorio al suelo mineral y cómo influyen en la fertilidad de este. ...
... Resultados similares informanMolina et al., (2018); mientras que describen mayores valores de acumulaciones en Ca y menoresde K (Fernández et al., 2016). También se conoce que en en plantas de Munrochloa ritchei la mayor acumulación se logra en magnesio(Kuruvilla et al., 2016).Los mayores aportes de materia orgánica producida por la hojarasca al suelo, es una cuestión de vital importancia para el enriquecimiento de los suelos, evidenciándose un mejor contenido nutricional en la especie forestal evaluada. El dosel por medio de la hojarasca no solo suministra materia orgánica, sino también regula la temperatura del suelo, por lo que la descomposición de la materia orgánica y el suministro de nutrientes ocurre de forma continua y paulatina, que contrarresta, a su vez, factores como la erosión del suelo, degradación de la tierra y desertificación, que hacen que la salud del suelo aumente FAO (2017).ISSN: 2310-3469 RNPS: 2347 Revista CFORES,septiembre-diciembre 2021; 9(3):454-469 ...
The research was carried out in the Sumidero Silvicultural Unit, belonging to Empresa Agroforestal Minas, with the objective of evaluating the contribution of leaf litter to the soil in stands of Pinus tropicalis Morelet. The collection of leaf litter was carried out in two sites: stand 1 with site quality I, stand 4 with site quality II; rectangular traps-collectors (1X0.5 m) were placed in each stand, in plantations of P. tropicalis, with ages between 15 and 24 years. Soil samples were obtained with and without leaf litter, in which the contents of nutrients (phosphorus, potassium, magnesium, calcium) and organic matter were determined. The results showed significant differences between soils with and without leaf litter, more accentuated in phosphorus and organic matter, with increases higher than 4.9 % and 3.9 % as a consequence of the accumulation of leaf litter; whereas, the highest contribution of nutrients and organic matter is produced in the surface of the soil and decreases, appreciably in the soils extracted from the soil pits made in the stands, maintaining the differences between these in the contents of phosphorus and organic matter.
... Since radial growth does not occur in bamboos, the aboveground biomass (AGB) increment is a function of new culm recruitment, which is predicted to fluctuate temporally depending on the emergence timing of new bamboo shoots. Numerous studies have shown that seasonal variation in litterfall in tropical forests corresponds to the drought period (Zhang et al. 2014), but information on the seasonal pattern of bamboo litterfall is limited (Ge et al. 2014;Kuruvilla et al. 2016;Toledo-Bruno et al. 2017). Annual estimates of NPP and its seasonal fluctuations will promote understanding of the factors that influence potential carbon sequestration rates. ...
... The peak likely reflects a response to drought stress (Detto et al. 2018;Reich and Borchert 1984). Similar seasonal patterns in litterfall production have been reported in both bamboos and tropical forests in the tropical monsoon climate zone (Kuruvilla et al. 2016;Nath et al. 2004;Zhang et al. 2014). A deeper understanding of the drivers that influence the seasonal pattern of litterfall production in bamboos will require an extended dataset on the relationship between litterfall and climate. ...
Aims
Accurate estimates of bamboo biomass and net primary productivity (NPP) are required to evaluate the carbon sequestration potential of bamboo forests. However, relevant data that are important for climate change mitigation, have rarely been collected in regions outside of East Asia and India. Information on seasonal patterns of NPP and its components will enable the quantification of factors that influence the carbon balance in bamboo forests. In this study, we quantified the aboveground biomass (AGB) and aboveground NPP of five major bamboo species in northern Laos using monthly data collected over a 12-month period.
Methods
All live culms in 10, 2 m × 2 m plots (for one monopodial bamboo species: Indosasa sinica) and 30 clumps per species (for four sympodial bamboo species: Bambusa tulda, Cephalostachyum virgatum, Dendrocalamus membranaceus and Gigantochloa sp.) were numbered and measured at breast height. We set 10 or 20 litter traps per species to collect litterfall. Censuses of dead and recruited culms and litterfall collection were performed once per month for 12 months.
Important Findings
The AGB was highest in I. sinica (59.87 Mg ha−1) and lowest in C. virgatum (11.54 Mg ha−1), and was mostly below the plausible global range for bamboos (32–256 Mg ha−1). The sympatric distribution of multiple bamboo species at the study sites may have suppressed the AGB in four of the five studied species. The aboveground NPP estimates were between 3.43 and 14.25 Mg ha−1 yr−1; those for D. membranaceus (8.20 Mg ha−1 yr−1) and I. sinica (14.25 Mg ha−1 yr−1) were comparable to mean global estimates for temperate evergreen forests (8.78 Mg ha−1 yr−1) and tropical moist forests (10.56 Mg ha−1 yr−1). High culm recruitment rates (15.20–23.39% yr−1) were major contributors to aboveground NPP estimates. Seasonal patterns of aboveground NPP were largely influenced by the phenology of the new culms. In the four sympodial bamboo species, new culms began to emerge following the onset of persistent rainfall, mainly in July and August. However, the sprouting of new culms in the monopodial species I. sinica followed a trend of increasing temperatures, mainly in March and April. Thus, our results indicate that bamboos have considerable potential for sequestering carbon in northern Laos, but that this potential may be affected by climate change.
... La descomposición de la hojarasca libera N, P, K, Ca, Mg y otros nutrimentos a diferentes tasas, en función de su calidad (Montagnini y Muñiz-Miret, 1999;Berg, 2000). Kuruvilla et al. (2016) examinaron la dinámica de la producción de hojarasca, descomposición y liberación de nutrimentos de Munrochloa ritchei (Munro) M.Kumar & Remesh, una especie de bambú rara y endémica de Ghats Occidentales, India. La disminución en su contenido de N y K, fue continua; mientras que, P, Ca y Mg mostraron fases de acumulación temporales, antes de la liberación final. ...
... Estos resultados indican poca liberación de Mg, en relación a la de K, patrón similar a lo documentado por Moro y Domingo (1996), quienes observaron en la hojarasca de Adenocarpus decorticans Boiss., en la Sierra de los Filabres, España, que el Mg registró una liberación de 0.96 % y K de 1.69 %. Sin embargo, en un estudio realizado por Kuruvilla et al., (2016) en Munrochloa ritchei, determinaron que el Mg fue el elemento de mayor liberación, con respecto al K. ...
El Matorral Espinoso Tamaulipeco está constituido por árboles y arbustos que producen gran cantidad de hojarasca esencial para el suelo y el ciclo de los nutrientes, el cual es complejo de entender. El objetivo del presente trabajo fue determinar el contenido de Ca, K, P, Mg, Cu, Fe, Mn y Zn durante el proceso de degradación de la hojarasca y comparar su dinámica en dos estaciones. La hojarasca se recolectó 15 días previos a cada estación y se dejó en campo para evaluar su descomposición (10 g), mediante la técnica de bolsa de nylon durante el invierno y la primavera. La tasa de descomposición (k, g g-1 año-1) fue de 0.002 y 0.003, respectivamente. En la estación de invierno, el Ca y P registraron una acumulación de 34.7 y 0.32 mg g-1, respectivamente; el K, liberó 7.2 y el Mg, 0.3 mg g-1; el Cu 1.0 µg g-1; el Fe incrementó 402.8 y el Mn 7.9 µg g-1; el Zn presentó una acumulación de 0.04 µg g-1. En primavera, el Ca tuvo una acumulación de 10.93 mg g-1 y el contenido de P fue 0.7 mg g-1. Al igual que en la temporada invernal, los minerales que registraron liberación fueron K (6.3 mg g-1) y Mg (0.49 mg g-1). Con respecto a Cu, Fe, Mn y Zn, se observó acumulación a razón de 2.7, 446.3, 6.3 y 16.1 µg g-1, respectivamente.
... This process is essential in tropical forests as those are environments with highly weathered soils (Poggiani 2012) and with low fertility (Vitousek & Sanford 1986). Because of that, the vegetation depends on the cycling of nutrients contained in plant debris for the absorption of nutrients (Kuruvilla et al. 2016, Rawat et al. 2010). In addition, litter production becomes essential for the functioning of the ecosystem, transferring nutrients to the soil (Pandey et al. 2007), maintaining soil fertility in forest ecosystems (Guendehou et al. 2014, Montagnini & Jordan 2002, Tripathi et al. 2006) and for the global carbon cycle (Berg & Mcclaugherty 2014). ...
Litter production plays an important role in the functioning of the ecosystem, providing several ecosystem services, such as nutrients cycling and carbon storage. We studied litter production patterns and its relationship with forest structure over a chronosequence of secondary forests in southern Bahia, Brazil. In the study area, 15 pairs of mature and secondary forest were used, in a chronological sequence, being 10, 25 and 40-year-old secondary forests and mature forests.Plots were created for the collection of aboveground biomass data, and within these plots, litter collectors were installed and monitored for 1 year. The results showed that litter production was lower in 10-year-old secondary forests when compared with older forests. On the other hand, in the 10-year-old forests, annual litter production represents 47.8% of the stored biomass, while
in mature forests annual litter production represents only 4%. We found that structural variables (basal area, number of stems and canopy opening) influence significantly litter production, as well as litter as percentage of forest biomass. The study emphasizes the importance of biomass production through litterfall in regenerating tropical forests, and its importance for carbon storage and for the maintenance of ecosystem services.
... Chemical properties of soil play a major role in crop production. Litter production, decomposition in both bamboo species are already studied (Thomas et al. 2014(Thomas et al. & 2016. Soils are not just to supply adequate nutrients alone but the nutrients to be in proper balance. ...
The present study was conducted to determine nutrient locking in biomass and soil of Munrochloa ritchiei and Ochlandra
setigera natural populations situated in the Nilambur Forest Division of Kerala. The storage of N, P, K, Ca and Mg in the
standing biomass of the M. ritchiei was 196.5±87.8, 1988.1±902.9, 977.6±542.1, 48.1±15.8 and 23.2±8.7 kg ha-1,
respectively. The soil nutrient status under the bamboo stand indicated that the total N, P and K content of the soil up to a
depth of 60 cm was 30.3±1.3, 81.03±4.01 and 22.97±1.30 t ha-1 respectively and that of Ca and Mg was 2.775±0.634 and
1.92 ±0.34 t ha-1 respectively. Studies on nutrient status of the plant and soil revealed that the total nutrient stored in the
plant parts was in the order Stem > Rhizome > Leaves+ Branches> Root. The nutrient storage in the standing biomass
stock was in the order P > K > Ca > N > Mg. In O. setigera, the total nutrients locked in the biomass components were
306.5±116.2 (N), 2085.9±698.0 (P), 658.8±228.7 (K), 52.1±16.1 (Ca) and 38.4±6.8 (Mg) kg ha-1. The total N, P, K, Ca and
Mg storage of the soil was 21.671±2.238, 83.308±5.106, 7.902±0.148, 1.598±0.702 and1.132±0.269 t ha-1 respectively.
... El elemento Mg presentó un movilidad lenta en ambas estaciones mostrando en invierno una liberación de -0.34 mg g -1 ps que equivale a un 9% de cantidad inicial y en primavera su liberación fue de -0.39 mg g -1 ps que es igual a 12% respecto a su cantidad inicial, seguido de K que presentó liberación de -7.2 a -6.3 mg g -1 ps igual a 63% y 59% respectivamente, respecto a su valor inicial, estos resultados no coinciden con un estudio hecho por Kuruvilla et al., (2016) en Munrochloa ritcheyi en donde encontró que Mg fue un elemento de mayor liberación y posteriormente siguió K sin embargo Moro et al., (1996), mencionan que en la hojarasca de Adenocarpus decorticans Boiss. En la Sierra de los Filabres (Almería), K mostró una liberación de - 1.69%, es el elemento que más fácilmente se liberó seguido por Mg con -0.96%, datos que coinciden con el orden de liberación en este proyecto de investigación. ...
In the era of climate change, bamboos can act as a superior carbon sink because of its fast growth rate and wide climatic adaptability. The clump structure, standing stock biomass and carbon storage of Ochlandra setigera located in the Nilambur Forest Division of Kerala was assessed in the present study. Sample plots were laid out and clump structure was recorded. The biomass and carbon storage were estimated by destructive sampling. The total number of culms of O. setigera during the first and second year of study was 29,477.28 and 31,404.24 per ha, respectively. The distribution of culms in height classes followed the logistic distribution whereas; girth class distribution of culms was best described by the Weibull (3P). The standing stock biomass of O. setigera was 73.4 ±30.3 t ha-1 and the stem and rhizome recorded the highest contribution towards the total biomass. The carbon storage of natural stand of O. setigera was 30.7 ±13.2 t ha-1. Soil carbon storage was to the tune of 117.538 ±29.919 t ha-1. The soil C concentration and stock decreased with depth and the top two layers (0-40 cm) recorded more than 80 % of the total carbon stock. With great biomass production and carbon storage in biomass and soil, O. setigera can play an important role in carbon sink forestry and there is an urgent need for conservation this species.
Background
Nitrogen (N) is an important macronutrient that controls the productivity of ecosystems and biological nitrogen fixation (BNF) is a major source of N in terrestrial systems, particularly tropical forests. Bamboo dominates theses forests, but our knowledge regarding the role of bamboo in ecosystem functioning remains in its infancy. We investigated the importance of a native bamboo species to the N cycle of a Neotropical forest.
Methods
We selected 100 sample units (100 m ² each) in a pristine montane Atlantic Forest, in Brazil. We counted all the clumps and live culms of Merostachys neesii bamboo and calculated the specific and total leaf area, as well as litter production and respective N content. Potential N input was estimated based on available data on BNF rates for the same bamboo species, whose N input was then contextualized using information on N cycling components in the study area.
Results
With 4,000 live culms ha ⁻¹ , the native bamboo may contribute up to 11.7 kg N ha ⁻¹ during summer (January to March) and 19.6 kg N ha ⁻¹ in winter (July to September). When extrapolated for annual values, M. neesii could contribute more than 60 kg N ha ⁻¹ y ⁻¹ .
Discussion
The bamboo species’ contribution to N input may be due to its abundance (habitat availability for microbial colonization) and the composition of the free-living N fixer community on its leaves (demonstrated in previous studies). Although some N is lost during decomposition, this input could mitigate the N deficit in the Atlantic Forest studied by at least 27%. Our findings suggest that M. neesii closely regulates N input and may better explain the high diversity and carbon stocks in the area. This is the first time that a study has investigated BNF using free-living N fixers on the phyllosphere of bamboo.
The present study was conducted in a tropical dry deciduous forest at Barnawapara wildlife sanctuary, Raipur, Chhattisgarh, India. Leaf litter decomposition and nutrient release were studied in four tree species viz., Shorea robusta C.F. Gaertn.f., Madhuca indica J.F. Gmel., Diospyros melanoxylon Roxb. and Schleichera oleosa (Lour.) Oken. The objectives of the study were to determine the weight loss and nutrient mineralization pattern of leaf litter of these four major species. The weight loss was fastest in S. robusta and slowest in M. indica. Monthly weight loss was positively related (P < 0.05) with the climatic factors (rainfall, temperature and relative humidity) except for M. indica for which the relationship was not significant. Weight remaining was inversely related (P < 0.01) to N and P concentrations, but was positively related to K concentration. The nutrient content in the residual litter decreased continuously with time for all species, except in the case of P for S. robusta and D. melanoxylon. We conclude that S. robusta decomposed at fasters rate followed by D. melanoxylon, S. oleosa and M. indica. The former species also released the two important nutrients (N and P) at a faster rate as compared to the other species. M. indica showed the slowest decomposition rate and nutrient release.
Coffee (Coffea arabica L.) production is important for its economic, ecological and social values in tropical areas. Whether coffee is grown under shade (SHD) or full sunlight (SUN), may have a direct impact on soil nitrogen (N) cycling, which can affect yield and agroecosystem sustainability. We studied N cycling in coffee farms in three municipalities in Puerto Rico and evaluated three ecosystem types in each: SUN coffee, SHD coffee and secondary forest (FOR). Aboveground litter dry matter and litter N inputs were quantified. Litter dry matter inputs (t ha-1year-1) were higher in SHD (2.15) and FOR (1.83), and were significantly greater than SUN (1.40). Litter N inputs (kg N ha-1year-1) were significantly lower in SUN (31) than in SHD (52) and FOR (43). Cycling of N was evaluated in detail in the municipality of Las Marias in SHD and SUN coffee. Litter N inputs (kg N ha-1year-1) to soil were significantly different between FOR (41) and SHD (56). The standing stock of N in aboveground biomass SHD was ∼3 times that in SUN, and total N input was twice that in SUN. However, soil N standing stocks were similar in SHD and SUN, indicating faster litter N turnover in SUN than in SHD ecosystems. By contrast, net soil N mineralization rates (kg N ha-1year-1) were ∼2 times higher in SHD (96) than in SUN (49), indicating that soil N turnover is greater in SHD than SUN. Our results suggest that litter N is mineralized at a slower rate in SHD than in SUN, whereas soil N is mineralized at a slower rate in SUN than in SHD. Higher inputs of N to soil, and soil N turnover in SHD may result in improved coffee production and associated forest biomass N uptake. Higher soil N mineralization rates in SHD coffee suggest improved ecosystem sustainability than in SUN coffee, presumably due to higher microbial activity, greater microbial diversity and substrate availability.
The carbon sequestration potential and litter dynamics of four priority bamboo species viz. Bambusa balcooa Roxb, B. bambos Voss, Ochlandra travancorica Benth and Thyrsostachys oliveri Gamble was studied in Thrissur and Palakkad districts of Kerala during 2010-2012. The bamboo clump and culm growth was recorded annually. Biomass production was estimated by destructive sampling of the six and seven year old clumps. Litterfall of the four bamboo species were quantified using litter traps and litter decomposition was studied by adopting standard litterbag techniques. The results of the study indicated that the average culm production of B. balcooa, B. bambos, O. travancorica and T. oliveri at the age of seven years was 7799, 7000, 29945 and 3725 culms ha-1 respectively. The frequency distribution of bamboo culms within a clump in different girth classes varied with species. The biomass production of bamboo clumps increased with age. The average biomass accumulation in six year old B. balcooa, B. bambos, O. travancorica and T. oliveri clumps was to the tune of 116.079, 31.660, 12.145 and 99.067 kg and that of seven year old clumps was 159.935, 51.334, 17.731 and 111.286 kg, respectively. Among the clump components like culm, branch, leaf, rhizome and root, culms contributed major share of biomass accumulated in a clump. Annual productivity of B. balcooa, B. bambos, O. travancorica and T. oliveri between sixth and seventh years was 18.57, 7.07, 0.89, and 5.92 Mg ha-1 year-1 , respectively. Linear and exponential allometric models used to predict above ground biomass (culm, branch, leaf and total) using height and girth at breast height was found to be significant and the log: log allometric equations were the best fit in most of the cases. Carbon concentration of the clump components varied significantly irrespective of species and the average carbon concentration in the components was 40.53 per cent. Above ground biomass components recorded a higher carbon concentration than below ground in all the bamboo species. Carbon sequestration of B. balcooa at the age of six and seven years was to the tune of 22.34±6.87 and 30.66±10.01 Mg ha-1 and that of B. bambos was 7.19±0.53 and 10.33±2.58 Mg ha-1 respectively. Meanwhile, carbon sequestration of O. travancorica at the age of six and seven years was 2.690±0.14 and 3.02±0.23 Mg ha-1 and that of T. oliveri was 18.66±2.19 and 21.14±6.15 Mg ha-1, respectively. Soil also played an important role in carbon sequestration. Soil carbon content and density declined with increasing depth. Total carbon density of soil under B. balcooa, B. bambos, O. travancorica and T. oliveri at the age of seven was 56.95±4.34, 62.86±6.26, 46.28±4.31 and 54.02±3.17 Mg ha-1, respectively. Monthly litter production of four bamboo species varied at different ages. Annual Litter production at the age of six years was to the tune of 4.064, 3.340, 1.846 and 4.488 Mg ha -1 year-1 in B. balcooa, B. bambos, O. travancorica and T. oliveri, respectively. Litter production increased with age and the litter production at the age of seven years in B. balcooa, B. bambos, O. travancorica and T. oliveri was 5.087, 3.909, 2.227 and 5.522 Mg ha-1 year-1, respectively. A biphasic pattern of litter decomposition, comprising an initial rapid phase followed by a slower phase was observed in all bamboo species. Mass loss rate in different bamboo species exhibited a good fit to exponential decay model. Decomposition rate of litter mass in different bamboo species was in the order O. travancorica > B. balcooa > B. bambos > T. oliveri. Concentration (per cent) of nutrients in the litter mass retrieved at monthly intervals varied in four species and the nutrient content in general was lower towards the end of decomposition. Concentration of N, P, K, Ca and Mg in the residual litter mass was highly variable at monthly intervals. Nutrient (%) remaining in the litter calculated from nutrient concentration and litter mass remaining declined with time in the case of all the nutrients in general with some accumulation phases. The nutrient release from the decomposing litter mass of bamboo species was in the order Mg> N> Ca> P> K. Results of the study indicated the greater carbon sequestration potential of bamboos compared to some tree species and possible huge Certified Emission Reduction generation. Litter dynamics studies suggest that B. balcooa, B. bambos, O. travancorica and T. oliveri have tremendous potential in regulating soil nutrient pool through litter decay and nutrient release and therefore can help in soil nutrient restoration and there by ecosystem reconstruction. Nowadays, cultivation of bamboo in non-forest areas is in focus to enhance the resource base to meet the raw material requirements of large and small scale industries. The four species studied are included in the list of priority species by National Mission on Bamboo Applications. Planters also have shown great interest in these species. Hence, results of the study will be useful as it will throw light on performance of these four species in non-forest areas under Kerala conditions.
of N, P and K were studied for a bamboo forest in the Garhwal Siwalik Himalaya, India. Bamboo culms are felled once in every fourth year and this felling cycle is continued to last one century. Most of the culms of bamboo had attained an age of 2 to 4 y in the forest studied. The relative contribution of various components to the standing state of biomass is in the order: bamboo culms > branches > leaves > herbs. Nutrient concentrations were higher in leaves than any other plant components. Among nutrients K showed the highest concentration, followed by N and then by P. About 63, 16and 73 kg ha-1 of N, P and K, respectively was recorded in standing biomass, out of which 5, 1 and 2 kg ha) of the respective element was returned to the soil. Lower standing state of nutrients, lower uptake and return in the studied forest can be attributed to lower age of bamboo culms, and to existing management practices. It was concluded that removal of bamboo culms in every four years for commercial purpose impoverished the soil nutrient status and thus the fertility of soil is poor under bamboo in the Garhwal Siwalik Himalaya.
We investigated litter chemistry, and patterns of mass loss and nutrient release
from leaf and sheath litter of three priority cultivated bamboo species, Bambusa cacharensis, B.
vulgaris and B. balcooa, to understand litter decomposition. The study was conducted in a
homegarden of Dargakona village in district Cachar, Assam, in northeast India. Leaf litter had
higher concentrations of N, P and K than sheath litter, whereas sheath litter had higher carbon,
ash free mass and cellulose. Percent weight loss decreased exponentially with time. Sheath
litter had slower rates of mass loss than leaf litter. The pattern of N release was biphasic, P
concentration exhibited an initial accumulation phase, and release of K occurred at all the
stages of decomposition. We discuss the ecological significance of decomposition dynamics of
bamboo litter – compared with litter of other cultivated tree species – for nutrient retention in
homegardens.
Although Asian bamboo species constitute a non-timber forest product of major cultural and economic importance, no detailed regional assessment of their distribution patterns has previously been made. To assess the potential of the existing bamboo species distribution data for production of regional mapping tools for planning the conservation of forest-based biodiversity, data on bamboo distribution and forest cover were combined. Over 1000 bamboo species from 60 genera of woody bamboos were incorporated, allowing the mapping of individual species or groups of species and genera, along with potential species richness and biodiversity hotspots. Over 6.3 million km2 of Asian forest potentially contains bamboo, with highest densities indicated from northeastern India through Burma to southern China, and through Sumatra to Borneo. The highest figures for potential species richness (144 spp per square km) were recorded in forests of south China, including Hainan Island. Despite substantial inadequacies and inconsistencies in knowledge of the taxonomy and distribution of bamboo species, this approach may provide a valuable tool for planning in situ conservation of forest biodiversity.
We examined the patterns of nitrogen (N) and phosphorus (P) gain, retention or loss in ten foliar tissues in a litterbag experiment
over 6 years at 18 upland forest sites in Canada, ranging from subarctic to cool temperate. N was usually retained in the
decomposing litter until about 50% of the original C remained. The peak N content in the litter was observed at between 72
and 99% of the original C remaining, with C:N mass quotients between 37 and 71 (mean 55). The rate of N release from the litters
was not related to the original N concentration, which may be associated with the generally narrow range (0.59–1.28% N) in
the litters. P was immediately lost from all litters, except beech leaves, with critical litter C:P mass quotients for P release
being in the range 700–900. The rate of P loss was inversely correlated with the original litter P concentration, which ranged
from 0.02 to 0.13%. The soil underlying the litterbags influenced the pattern of N and P dynamics in the litters; there were
weak correlations between the N and P remaining at 60% C remaining in the litters and the C:N and C:P quotients of the surface
layer of the soil. There was a trend for higher N and P retention in the litter at sites with lower soil C:N and N:P quotients,
respectively. Although there was a large variation in C:N, C:P and N:P quotients in the original litters (29–83, 369–2122
and 5–26, respectively), and some variation in the retention or loss of N and P in the early stages of decomposition, litters
converged on C:N, C:P and N:P quotients of 30, 450 and 16, when the C remaining fell below 30%. These quotients are similar
to that found in the surface organic matter of these ecosystems.
A field study was conducted in the moist deciduous forests of the Western Ghats (India) to test the following three hypotheses: (1) Litter production in tropical forests is a function of the floristic composition, density, basal area and disturbance intensity; (2) Decay rate constants of tropical species is an inverse function of the initial lignin/nitrogen ratio; (3) Decomposition rates in tropical forests are faster than temperate forests.Litter fall was estimated by installing 63 litter traps in the moist deciduous forests of Thrissur Forest Division in the Western Ghats at three sites. Litter fall followed a monomodal distribution pattern with a distinct peak during the dry period from November–December to March–April.Dillenia pentagyna, Grewia tiliaefolia, Macrosolen spp.,Xylia xylocarpa, Terminalia spp.,Lagerstroemia lanceolata, Cleistanthus collinus, Bridelia retusa, andHelicteres isora were the principal litter producing species at these sites. The annual litter fall ranged from 12.18 to 14.43 t ha−1. Structural attributes of vegetation such as floristic composition, basal area, density and disturbance intensity did not directly influence litter fall rates.Leaf litter decay rates for six dominant tree species were assessed following the standard litter bag technique. One hundred and eight litter bags per species containing 20 g samples were installed in the forest floor litter layer at the same three sites selected for the litter fall quantification exercise. The residual litter mass decreased linearly with time for all species. In general, less disturbed sites and species adapted to higher nitrogen availabilities exhibited relatively higher decay rate coefficients (k). The rapid organic matter turnover observed in comparison with published temperate forest litter decay rates confirms that tropical moist deciduous forest species are characterised by faster decomposition rates.Mean concentrations of N, P and K in the litter were profoundly variable amongst the dominant species. Initial nitrogen content of the leaf litter varied from 0.65 to 1.6%, phosphorus from 0.034 to 0.077% and potassium from 0.25 to 0.62%.C. collinus, an understorey shrub consistently recorded the lowest litter concentrations for all nutrients. The overriding pattern is one of higher nutrient levels in the overstorey leaf litter and lower concentrations in the understorey litter. Furthermore, as decomposition proceeded, the nitrogen concentration of the residual biomass increased.
The decomposition rates and N. S and P dynamics of flowenne dogwood (Cornus florida). red maple (Acer rubrum) and chestnut oak (Quercus prinus) litter were examined during 2 years in a mixed deciduous forest in the southern Appalachians. Litter of the three species decomposed in the following order (fastest to slowest): flowering dogwood > red maple > chestnut oak. Initial mass losses (first 6 months) were most highly positively correlated with concentrations of ethanol-soluble and total soluble components. First-year annual decay rates were most highly negatively correlated with initial % lignin and lignin-to-N ratios. Second-year decay rates were significantly slower than first-year rates for flowering doewood and red maple litter, but not for chestnut oak. This was apparently due to the greater proportion of labile materials initially present in flowering dogwood and red maple litter Relative concentrations of N, S and P increased during the decomposition of each litter type. following any initial leaching losses. In all cases, the increases in N. S and P concentrations exhibited negative linear relationships to % mass remaining. For all three elements the slopes of these relationships were correlated with decay rates, indicating a greater increase in N. S and P concentrations per unit mass lost in faster decomposing litter types. Changes in the absolute amount of N (net immobilization or net release) followed a typical three component curve (leaching, immobilization and release phases). Nitrogen release began when C-to-N ratios decreased to between 25 and 34, Patterns of P and S fluxes varied more among litter types. Only flowering dogwood litter, with a final C-to-P ratio of 305 appeared to release P by the end of the study. Flowering dogwood litter also had a low initial C-to-S ratio (236) and displayed an immediate net release of S which continued throughout the study. The other litter types, which had higher initial C-to-S ratios, immobilized S throughout the study.
The rates of loss of dry matter, phosphorus, magnesium, calcium, potassium, and sodium during decomposition of plant materials were studied in mature Eucalyptus obliqua (L'Herit.) forests in southeastern Australia. The loss of elements follows the order Na > K > Ca > Mg > P, and can be largely explained by the behavior of these elements in terms of both mobility within the living biomass and of leaching from the forest canopy. The difference with respect to phosphorus between the mobility series for E. obliqua litter and that for the litter of some Russian hardwoods suggests that the two plant systems differ also with respect to the cycling and mobility of phosphorus within the living biomass.
The climatic influence on plant litter decomposition has been successfully correlated on a regional level by using estimated actual evapotranspiration (AET) and annual mass loss. This approach was applied to decomposition studies carried out in a transect along Sweden with litter incubated in four different forest types. A unified needle litter was used and among 14 Scots pine sites about 80% of the mass-loss rate could be explained. A simple model was made on the influence of both climate and nutrient concentrations (nitrogen and phosphorus) on mass-loss rate. About 90% of the first-year mass loss could be explained by this approach. As early decomposition stages were studied (<40%) no influence of lignin was observed.
Recently, considerable attention has been paid to the establishment of large scale plantations of reed bamboo (Ochlandra travancorica Benth) and its introduction in the home gardens of Kerala, India. As in forest ecosystems, the decomposition and nutrient release of leaf litter are supposed to play an important role in the nutrition of bamboo stands. The mass loss of reed bamboo was studied using a litter bag in a predominantly reed growing area at Vazhachal situated in the southern Western Ghats of India. Two sites, one in a pure reed patch and the other in a teak plantation with reed under growth, were selected. Results of the study indicated that the exponential model proposed by Olson [1] was the best fitting model to work out the annual decomposition rate constant of reed leaf litter. These rate constants varied from 0.234 at Site 1 to 0.229 at Site II and were not different between the two sites. The time for 50% decomposition was three months and that of 95% was 13 months. The decomposition rate was highest in July and it was strongly and positively correlated with rainfall and soil moisture. Release of nutrients from the leaf litter varied with the type of element, and the nutrient mobility from decomposing reed leaf litter was in the order K > N > Mg > Ca > P.
Biomass productivity and nutrient cycling in a Bambusa bambos plantation aged 4, 5, and 6 years were studied. The dry matter production of above-ground biomass increased progressively with age. Nutrient quantities in bamboo stands were in a range of 1–2 t ha-1 for N and K, 0.5–1 t ha-1 for Ca and Mg, and 0.1–0.2 t ha-1 for P. Nutrient concentrations increased with the age of the plantation. About 10% year-1 the nutrients present in the biomass of the bamboo stand are recycled to the soil by litter fall.
Litter of high quality is required for increased soil organic matter turnover and improved crop production in tropical agroecosystems.
Studies on litter quality using plant residues have produced inconsistent results. This study reports on previously published
data on litter quality, in an attempt to define universal chemical determinants controlling N release in tropical agriculture.
N concentrations and polyphenol/N ratios are determinants of the N release of plant residues with limited N concentrations,
i.e. of <2% and <1%, respectively. Lignin levels and lignin/N ratios were not observed to be good predictors of N release.
The C/N ratio was found to be the best determinant of N release for a wide range of residue N concentrations. More specifically,
critical levels of C and plant nutrients which limit the enzyme activities of microbial decomposers were found to be important
for determining nutrient release.
The dynamics of three major mineral nutrients (K, Ca, Mg) and six heavy metals (Fe, Mn, Zn, Cu, Pb and Cd) were studied in decomposing natural, unpolluted litter in two forest types: Scots pine needle litter in a pure Scots pine forest and oak‐hornbeam leaf litter in a mixed oak‐hornbeam stand. Of the mineral nutrients, only K in the oak‐hornbeam system showed a significant decrease in concentration during the course of litter decomposition. For Ca and Mg in both systems and for K in the Scots pine system no clear relation between concentration and accumulated litter‐mass loss was observed. On the other hand, for Fe, Zn, Pb and Cd at both sites, as well as for Mn in the oak‐hornbeam stand and Cu in the Scots pine stand highly significant positive relations were found between heavy metal concentrations and accumulated mass loss. A decrease in concentration was noted only in the case of Mn in the Scots pine system. No clear pattern was found for Cu in the oak‐hornbeam stand. Concentrations of heavy metals in the decomposing litter reached levels at or above those reported to retard decomposition in other studies. At the oak‐hornbeam stand increased also the absolute amounts of Fe, Zn, Pb and Cd.
The popular view of primary and old secondary tropical rainforests is that they occur on infertile soils, have most of the nutrients in the above-ground living matter, and maintain a high production by rapid and efficient nutrient cycling. This paradigm pervades much land use planning rationale in forested areas in the tropics.In this paper, rainforest nutrient cycles are outlined and the methodological difficulties of work on them are emphasized. There is a shortage of information on nearly every aspect. It is concluded that the popular view is not fully justified even from the available data. Some rainforests occur on fertile soils with a high proportion of at least some nutrients below ground. In some cases there appears to be a substantial yearly loss of nutrients from the ecosystem and sometimes nutrient cycling is slow.Rainforest nutrition is immensely complex and shows many differences from one area to another. It is concluded that much more research is necessary before useful generalizations are possible.
All India Coordinated Project on Taxonomy (aicoptax) Grasses & Bamboos (Part II) Bamboos of Peninsular India
- M S Kumar
Kumar, M. S. 2011. All India Coordinated Project on
Taxonomy (aicoptax) Grasses & Bamboos (Part II)
Bamboos of Peninsular India. KFRI Research
Report.
Organic accretion, decomposition and mineralisation. pp 433-480 Management of Soil, Nutrients and Water in Tropical Plantation Forests
- O ' Connell
- A M K V Sankaran
O'Connell, A. M. & K. V. Sankaran. 1997. Organic
accretion, decomposition and mineralisation. pp
433-480. In: E. K. S. Nambiar & A. G. Borwn (eds.)
Management of Soil, Nutrients and Water in
Tropical Plantation Forests. ACIAR, Australia.
Organic accretion, decomposition and mineralisation
- A M K V O'connell
- Sankaran
O'Connell, A. M. & K. V. Sankaran. 1997. Organic
accretion, decomposition and mineralisation. pp
433-480. In: E. K. S. Nambiar & A. G. Borwn (eds.)
Management of Soil, Nutrients and Water in
Tropical Plantation Forests. ACIAR, Australia.