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Soil Properties, Litter Dynamics and Biomass Carbon Storage in Three-Bamboo Species of Sub-Himalayan Region of Eastern India
2022
Kumar, P Surath | Shukla, Gopal | Nath, Arun Jyoti | Chakravarty, Sumit
Information on biomass carbon storage in bamboo plantations/groves at local or regional landscapes is crucial to understand its potential in carbon stock management and climate change mitigation. The present work aims to study soil properties, litter dynamics and biomass carbon storage for the three common bamboo species from the Terai region of Indian Eastern Himalayas. Bambusa nutans, Dendrocalamus giganteus and Melocanna baccifera groves were selected for the present study. The soil pH, moisture and electrical conductivity under different bamboo groves of three species varied significantly, but moisture and electrical conductivity responded inconsistently with increasing soil depth. Similarly, the amount of soil available primary nutrients also varied significantly, where soils of M. baccifera grove were quantified with highest amount of these nutrients at all depths. M. baccifera grove produced the highest litter, although the difference with the other two groves was non-significant. The amount of oxidizable soil organic carbon quantified varied significantly among the bamboo groves, with the highest SOC content under the M. baccifera grove. The decomposition rate gradually increased with time, and within 9 months, the entire litter got decomposed. The annual return of nutrients was in the order N > K > P. The total biomass of D. giganteus, B. nutans and M. baccifera was estimated at 270.97, 127.21 and 16.31 Mg ha⁻¹, respectively. Based on the higher R² and adj R², and lower AIC and HQC, Model 1 was more appropriate for B. nutans and D. giganteus, whereas Model 2 was suitable for M. baccifera. The ecosystem carbon stock of D. giganteus was significantly (163.28 Mg ha⁻¹) higher than the other two species because of its significantly higher biomass carbon accumulation. This amount of biomass carbon storage and ecosystem carbon stock is comparable with agroforestry and forest ecosystems in the study region or elsewhere. The present study suggests these bamboos can be a feasible option for carbon farming and carbon trading, climate change adaptation and mitigation, apart from its contribution in social and economic contributions to the region’s rural life. Therefore, value addition and nationalizing of bamboo are recommended to improve rural folks’ livelihood. Encouraging value-added bamboo products can be negative feedback to climate change because of their durability and thus permanency of carbon stored in it.
Показать больше [+] Меньше [-]Sympodial bamboo species differ in carbon bio-sequestration and stocks within phytoliths of leaf litters and living leaves
2016
Xiang, Tingting | Ying, Yuqi | Teng, Jiangnan | Huang, Zhangting | Wu, Jiasen | Meng, Cifu | Jiang, Peikun | Tang, Caixian | Li, Jianmin | Zheng, Rong
Phytolith-occluded carbon (PhytOC) with high resistance against decomposition is an important carbon (C) sink in many ecosystems. This study compared concentrations of phytolith in plants and the PhytOC production of seven sympodial bamboo species in southern China, aiming to provide the information for the managed bamboo plantation and selection of bamboo species to maximize phytolith C sequestration. Leaf litters and living leaves of seven sympodial bamboo species were collected from the field sites. Concentrations of phytoliths, silicon (Si), and PhytOC in leaf litters and living leaves were measured. Carbon sequestration as PhytOC was estimated. There was a considerable variation in the PhytOC concentrations in the leaf litters and living leaves among the seven bamboo species. The mean concentrations of PhytOC ranged from 3.4 to 6.9 g kg⁻¹ in leaf litters and from 1.6 to 5.9 g kg⁻¹ in living leaves, with the PhytOC production rates ranging from 5.7 to 52.3 kg e-CO₂ ha⁻¹ year⁻¹ as leaf litters. Dendrocalamopsis oldhami (Munro) Keng f. had the highest PhytOC production rate. Based on a bio-sequestration rate of 52.3 kg e-CO₂ ha⁻¹ year⁻¹, we estimated that the current 8 × 10⁵ ha of sympodial bamboo stands in China could potentially acquire 4.2 × 10⁴ t e-CO₂ yearly via phytolith carbon. Furthermore, the seven sympodial bamboo species stored 5.38 × 10⁵ t e-CO₂ as PhytOC in living leaves and leaf litters in China. It is concluded that sympodial bamboos make a significant contribution to C sequestration and that to maximize the PhytOC accumulation, the bamboo species with the highest PhytOC production rate should be selected for plantation.
Показать больше [+] Меньше [-]Removal of Disperse Red dye by bamboo-based activated carbon: optimisation, kinetics and equilibrium
2013
Wang, Lianggui
This research involved the use of response surface methodology (RSM) to investigate the adsorption of Disperse Red 167 dye onto the bamboo-based activated carbon activated with H3PO4 (PBAC) in a batch process. F400, a commercially available activated carbon, was used in parallel for comparison. Analysis of variance showed that input variables such as the contact time, temperature, adsorbent dosage and the interaction between the temperature and the contact time had a significant effect on the dye removal for both adsorbents. RSM results show that the optimal contact time, temperature, initial dye concentration and adsorbent dosage for both adsorbents were found to be 15.4 h, 50 °C, 50.0 mg L(-1) and 12.0 g L(-1), respectively. Under these optimal conditions, the removal efficiencies reached 90.23 % and 92.13 % for PBAC and F400, respectively, with a desirability of 0.937. The validation of the experimental results confirmed the prediction of the models derived from RSM. The adsorption followed a nonlinear pseudo-first-order model and agreed well with the Freundlich and Temkin isotherm as judged by the levels of the AICc and the Akaike weight. Furthermore, the thermodynamics analysis indicated that, for both adsorbents, the adsorption was a physical process that was spontaneous, entropy-increasing and endothermic.
Показать больше [+] Меньше [-]What determines selection and abandonment of a foraging patch by wild giant pandas (Ailuropoda melanoleuca) in winter?
2009
Zhang, Zejun | Zhan, Xiangjiang | Yan, Li | Li, Ming | Hu, Jinchu | Wei, Fuwen
Background, aim, and scope Foraging patches can be described as a nested hierarchy of aggregated resources, implying that study of foraging by wild animals should be directed across different spatial scales. However, almost all previous research on habitat selection by the giant panda has concentrated upon one scale. In this research, we carried out a field study to understand foraging patch selection by giant pandas in winter at both microhabitat and feeding site scales and, for the first time, attempted to understand how long it would stay at the feeding sites before moving on. Materials and methods The field survey was conducted from November 2002 to March 2003 at Fengtongzhai Nature Reserve (102°48'-103°00' E, 30°19'-30°47' N), Baoxing County of Sichuan Province, China, to collect data in both microhabitat and control plots. The microhabitat plots were located by fresh feces or foraging traces left by giant pandas, and the control plots were established to reflect the environment. Within each microhabitat plot, one 1 x 1 m² plot was centralized at the center of each feeding site, in which numbers of old bamboos and old shoots, including eaten and uneaten, were counted, respectively. Results The results showed that winter microhabitats selected by this species were characteristic of gentle slopes and high old-shoot proportions and that the latter was even higher at feeding sites. Two selection processes, namely, from the environment to microhabitats and from the latter to feeding sites, were found during this species' foraging patch utilization. Giant pandas preferred to eat old shoots to old bamboo at feeding sites in winter and did not leave unless old-shoot density fell to lower than the average in the environment. Discussion Both microhabitats and feeding sites selected by giant pandas were characteristic of high old-shoot density, indicating that the preferred food item had a significant influence upon its foraging patch selection. The preference for gentle slopes by giant pandas was presumed to save energy in movement or reflect the need to sit and free its fore-limbs to grasp bamboo culms when feeding but also seemed to be correlated with an easier access to old shoots. The utilization of old shoots at feeding sites was assumed to help maximize energy or nutrient intake during their foraging. Conclusions The difference between microhabitat plots and control plots and between microhabitats and feeding sites uncovered a continuous selection process from the environment via microhabitats to feeding sites. The utilization of old shoots at feeding sites was parallel to the marginal value theorem. The selection and abandonment of foraging patches by giant pandas was an optimal behavioral strategy adapted to their peculiar food with high cellulose and low protein. Recommendations and perspectives Our results uncovered the importance of multiple scales in habitat selection research. To further understand the process of habitat selection, future research should pay more attention to resolve the question of how to locate foraging patches under dense bamboo forests by the giant panda, which was traditionally considered to have poor eyesight, although our research has answered what type of habitats the giant panda prefers and when to leave.
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