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[en] Tamarix nilotica is an important medicinal plant grows throughout the Kingdom, except in mountains on high altitude. Propagation of T. nilotica through cuttings and seeds are limited. To supplement harvesting of active ingredient from plants, alternative method for the purpose has been developed. Stem node cuttings were subjected to in vitro culture under the influence of various cytokinin to induce shoot proliferation. Maximum shoot stimulation was found on MS medium comprising 1.0 micro M TDZ followed by 2.5 micro M BA, Kn and 2ip. The number of shoots declined as the concentration of cytokinin increased. A lower shoots obtained on 5.0 and 10.0 micro M concentration of all the four cytokinins tested. After fair multiplication, individual shoots were subjected to different concentration of auxins IBA, NAA, 2,4-D and AA 2.5-10.0 micro M for root induction. Initial screening did not result desired rooting on MS medium. Therefore, pulse treatment of 100 micro M IBA was given to the isolated shoots for 5, 10 and 15 days time. Incubation for 10 days on MS medium supplied with 100.0 micro M resulted in maximum rooting when transferred on MS medium alone. Well rooted microshoots were exposed to four types of soil mixtures for acclimatization of plants. Among these soils, sand and FYM gave 100 percentage survival under controlled green house conditions. This protocol would be helpful in regeneration and conservation of this plant species; and provide an alternative source of biomass for pharmaceutical active ingredients. (author)
[en] Miscanthus lutarioriparius, is a perennial C4 weeds. In this study, tissue culture responses were evaluated in four genotyoes of M. lutarioriparius which collected from the Yangtze River basin. A total of four types of callus with different characteristics and induction frequencies were induced from four genotypes immature inflorescences on medium Murashige and Skoog (MS) containing 4.0 mg/L 2,4-dichlorophenoxyacetic acid (2, 4-D). Only ML04 generated the embryogenic callus. According to the length of immature inflorescences, they divided into three inflorescences developmental stages which generated different induction percentages of embryogenic callus. Developmental stage B with 50-100 mm length inflorescence generated the highest induction percentages of embryogenic callus. The regeneration rate was 65.56 percent (4.0 mg/L kinetin), 91.50 percent (5.0 mg/L KT) and 26.67 percent (6.0 mg/L KT) from embryogenic callus, respectively. The shoots were transferred onto the Murashige and Skoog (MS) basal medium for rooting, the rooting rate was 100 percent. (author)
[en] Polarimetric Synthetic Aperture Radar Interferometry (Pol-InSAR) is an active radar remote sensing technique based on the coherent combination of both polarimetric and interferometric observables. The Pol-InSAR technique provided a step forward in quantitative forest parameter estimation. In the last decade, airborne SAR experiments evaluated the potential of Pol-InSAR techniques to estimate forest parameters (e.g., the forest height and biomass) with high accuracy over various local forest test sites. This dissertation addresses the actual status, potentials and limitations of Pol-InSAR inversion techniques for 3-D forest parameter estimations on a global scale using lower frequencies such as L- and P-band. The multi-baseline Pol-InSAR inversion technique is applied to optimize the performance with respect to the actual level of the vertical wave number and to mitigate the impact of temporal decorrelation on the Pol-InSAR forest parameter inversion. Temporal decorrelation is a critical issue for successful Pol-InSAR inversion in the case of repeat-pass Pol-InSAR data, as provided by conventional satellites or airborne SAR systems. Despite the limiting impact of temporal decorrelation in Pol-InSAR inversion, it remains a poorly understood factor in forest height inversion. Therefore, the main goal of this dissertation is to provide a quantitative estimation of the temporal decorrelation effects by using multi-baseline Pol-InSAR data. A new approach to quantify the different temporal decorrelation components is proposed and discussed. Temporal decorrelation coefficients are estimated for temporal baselines ranging from 10 minutes to 54 days and are converted to height inversion errors. In addition, the potential of Pol-InSAR forest parameter estimation techniques is addressed and projected onto future spaceborne system configurations and mission scenarios (Tandem-L and BIOMASS satellite missions at L- and P-band). The impact of the system parameters (e.g., bandwidth, NESZ, ambiguities) and the operation scenario (e.g., temporal decorrelation due to a repeat-pass orbit) is evaluated and discussed with respect to the retrieval of the forest parameters. The study is supported and validated by using repeat-pass Pol-InSAR data at L- and P-band acquired by DLR's E-SAR system over Remningstorp (BioSAR 2007, hemi-boreal forest), Krycklan (BioSAR 2008, boreal forest) and Traunstein (TempoSAR 2008 and 2009, temperate forest) test sites. The simulated spaceborne data sets generated during the BioSAR 2007 campaign are used to carry out the performance analysis.
[en] Nowadays most studies of drying processes dynamics are established on empirical models without clear physical meanings, which could not predict the drying characteristic on different dryers. In order to describe the change of temperature and water content in the cut tobacco in different dryers, a mathematical model based on heat and mass transfer phenomena was developed, and the model employed the relationship of equilibrium moisture content and air humidity as basis, the difference of moisture between biomass and wet air as mass transfer driver, and the difference of temperature between biomass and wet air as heat transfer driver. The drying experiments under different air temperature and humidity are carried out on the batch rotary dryer, and the variance of temperature and moisture content in the biomass is obtained by using infrared thermometer and oven. The model is validated by two parameters with experiment data under each condition of air temperature and humidity. The results show that the drying dynamic model is well on accuracy and universality, and it could be applied on different drying device to predict the characteristic of kinds of drying processes. (Author)
[en] The complicated nature of gas-solids' physical properties have challenged the researchers over past decades who have led their efforts in developing its' flow sensing and measurement methods. The term 'gas-solid flow' signifies dilute- or dense-phase flow with a very little concentration of solids. For conducting such flow measurement, generally velocity profile and volumetric concentration of the flow particles being conveyed are needed to be measured. An important application of gas-solid flow has taken root in the form of biomass flow in pneumatic conveying systems, and its' online measurement has proven to be an exigent research pursuit. Additionally the other applications have been explored in power plants, food, chemical and automobiles industries as well. This paper aims at exploring the evolution of flow measurement methods along with a brief explanation on existing fundamental sensing techniques. Furthermore, the most recent patents developed for such measurements in pneumatic conveying pipelines are scrutinized along with their concomitant pros and cons
[en] The stocks and characteristics of coarse woody debris (CWD) are expected to reflect forest stand features. However, despite their importance, there have been no reports of CWD stocks and characteristics in the Qinling Mountains. We measured the CWD stocks in different CWD types, decay classes and diameter classes of the five forest types in the Qinling Mountains. The highest biomass of CWD was the Pinus tabulaeformis forest (12.57 t-hm /sup -2/), occupied 5.66 percentage in the biomass of this forest, the lowest occupied 1.03 percentage in Betula albo-sinensis forest (1.82 t-hm /sup -2/). Our results revealed that there was a strong correlation between CWD and forest biomass. When the CWD biomass were 9.9 t-hm /sup -2/ and 11.6 hm /sup -2/, the biomass of Pinus armandi forest and P. tabulaeformis forest reached maximum, respectively. CWD is particularly important for biodiversity, but the importance of CWD in the control of diversity in forest systems has not been fully appreciated and certainly has not been evaluated intensively within China, especially in Qinling forests. In our research, we used species richness (S), Shannon-Wiener index (H), Simpson index (D) and Pielou evenness index (J) to assess the diversity of plant community. According to our analysis, we found 1) the effect of CWD biomass on these a diversity index was dependent on tree, shrub and herb in the five forest types, 2) the impacts of CWD biomass on understory biodiversity were more obvious, 3) With the increase of CWD biomass, the species richness (S), Shannon-Wiener index (H) and Simpson index (D) of understory increased significantly. Our results suggested that there was a relatively lower CWD biomass in the Qinling Mountains, but it had significant effects on forest biomass and diversity of plant community. Reserving CWD was important for eco-forestry, but how many and how characteristic of CWD should be retained need further research. Development of CWD reasonable strategies was indispensable for future forest management. (author)
[en] Biomass mapping using satellite imagery is a rapidly evolving field that has been greatly facilitated in recent years by the advent of LiDAR remote sensing coupled with co-located field measurements. The biomass map of Africa that we published in 2008 did not take direct advantage of coincident field and LiDAR measurements, as our more recent efforts have. The criticisms of our earlier map by Mitchard et al (2011 Environ. Res. Lett. 6 049001) are duly noted and worthwhile, although they are also limited in several respects that we describe. Most notably, they assess our map with field data sets that are only representative of a subset of conditions across the study domain, thus they not only inadequately characterize undisturbed tropical forest regions but also the diverse disturbance dynamics that are captured in satellite imagery. We point out the limitations of their assessment and focus on a way forward, moving beyond both inadequate field sampling and remote sensing to an approach the captures the full range of dynamics by directly coupling field and satellite measurements. (reply)
[en] The relationship between diversity and productivity of plant community under plant invasion has been not well known up to now. Here, we investigated the relationship between diversity and productivity under plant invasion and studied the response of species level plant mass to species richness in native and invaded communities. A field experiment from 2008 to 2013 and a pot experiment in 2014 were conducted to study the effects of plant invasion on the relationship between diversity and productivity and the response of species level plant mass to species richness in native and invaded communities. The community level biomass was negatively correlated to plant species richness in invaded communities while the same relationship was positive in native communities. The species level plant mass of individual species responded differently to overall plant species richness in the native and invaded communities, namely, most of the species’ plant mass increased in native communities, but decreased in invaded communities with increasing species richness. The complementarity or selection effects might dominate in native communities while competition effects might dominate in invaded communities. Accordingly, the negative relationship between diversity and productivity under plant invasion is highlighted in our experiments.
[en] The quick decrease of the fossil fuels has taken to the search of renewable sources of energy. Cuba has in the biomasses one of the biggest potentialities of sources renewable of energy, but even with a small exploitation. The purpose of increasing the employment of the sources renewable of energy, in particular the biomasses one requires evaluation of the capacities with which it counts our country. Presently work the results of an are presented The study carried out directed to the evaluation of these sources focused basically to the possibility of their employment in processes thermochemical. The evaluation of the is attacked availability of these energy resources, their main ones characteristic, the potentialities are also determined of use of the selected biomasses. Equally you it makes an estimate of the availability of the biomasses chosen in dependence of the behavior of its consumption, for finally to carry out an appreciation of the one potential of energy obtaining starting from her and its technician-economic feasibility. (author)