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561.
An experiment was conducted to determine the influence the time of brush-cutting can have on plant regrowth and attractiveness
to herbivores that browse in linear corridors. The influence of cutting time on leaf flush and senescence, shoot morphometry,
and biomass was measured for 3 consecutive years after initial brush-cutting. Results indicate that morphological and phenological
attributes of three woody deciduous plants were influenced by the timing of brush-cutting for up to 3 years after initial
cutting. Brush-cutting generally stimulated plants to produce larger than normal shoots and delay leaf senescence. The degree
to which plants were affected, however, varied with the timing of initial cutting and the species in question. Generally,
plants cut later in the year resprouted more vigorously and were taller in the third year after cutting but produced less
overall biomass than when cut earlier. In the years following brush-cutting, plants cut earlier flushed leaves earlier in
the spring but delayed leaf senescence in the fall when compared to uncut controls. Results of these trials suggest that brush-cutting
time influences plant response and several plant attributes known to influence plant attractiveness to moose and other herbivores.
We therefore recommend that roadside and railside vegetation management plans consider the influence of cutting time on plant
regrowth. Such considerations can ensure that brush is cut to reduce the attractiveness of plant regrowth in these linear
corridors, reduce the utilization of such brush by herbivores, and, as such, mitigate collision risk between motorists and
herbivores such as moose. 相似文献
562.
Li H Chen Y Crittenden J Hand D Taylor R 《Journal of the Air & Waste Management Association (1995)》2006,56(8):1155-1166
A high-efficiency particulate air (HEPA)-carbon filtration system was developed by the Access Business Group, LLC, to reduce the indoor levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). The HEPA filter removes the particle-bound PCDD/Fs, and the carbon filter removes the gaseous fraction. Because of the toxicity of PCDD/Fs, it is very difficult to handle them in the laboratory. In this study, mathematical modeling was performed to evaluate the performance of the HEPA-carbon filtration system for PCDD/Fs removal and to optimize its design and operation. The model was calibrated with experimental data conducted with toluene in a sealed room. Model simulations with four selected congeners demonstrated that it takes approximately 1 hr for the indoor air treatment system to reach the maximum removal efficiency and that the carbon air filter has a life time of 10(7) yr for dioxin removal. Given a zero emission from the HEPA filter, the overall removal efficiency is 78.7% for 2,3,7,8-tetrachloro dibenzo-p-dioxins, 89.8% for octa-chlorodibenzodioxin, 78% for tetra-chlorodibenzofuran, and 89.8% for octa-chlorodibenzofuran. The larger the mass emission from the HEPA filter, the lower the overall removal efficiency, and the larger the ratio of the filter flow rate (Q(f)) to the room flow rate (Q), the higher the overall removal efficiency. When the ratio of Q(f)/Q is 15, an overall removal efficiency of 90% can be reached for all four of the selected compounds. The removal of the four selected compounds does not change as the relative humidity increases < or = 90%. 相似文献
563.
Decreasing reliance on mineral nitrogen--yet more food 总被引:2,自引:0,他引:2
Higher crop production normally demands higher nutrient application rates and consequently increased mineral nitrogen use. With food demand for 2030 estimated around 2800 mill. tonnes (t) yr-1, the corresponding mineral N consumption figure is 96 mill. t (78 mill. t yr-1 in 1995/1997). Global-level mineral N losses to the environment from mineral fertilizer use are currently 36 mill. t yr-1, worth USD 11,700 mill. and with adverse environmental impacts. However, innovative fertilizer-use efficiency (FUE) technologies enable increased production with a less than a proportionate increase in mineral-N use. Moreover, nitrogen-nutrient supplies can be augmented through improvements in agricultural production systems and in the exploitation of alternative sources such as biological nitrogen fixation (BNF). By 2030, with adequate policy, technology transfer, research and investment support, the on-farm adoption of BNF and FUE technologies could generate savings of 10 mill. t yr-1 of mineral N, worth USD 3300 mill. 相似文献
564.
A Study of Physicomechanical and Morphological Properties of Starch/Poly(vinylalcohol) Based Films 总被引:2,自引:0,他引:2
Dipa Ray Papri Roy Suparna Sengupta Siba Prasad Sengupta Amar K. Mohanty Manjusri Misra 《Journal of Polymers and the Environment》2009,17(1):56-63
Starch/Poly(vinylalcohol) blends in two different ratios (60:40 and 50:50) were prepared with glycerol as a plasticizer. Films
were cast by a solution casting method. One set of films were filled with 10 wt% of unmodified bentonite clay and another
set of films were crosslinked with epichlorohydrin in an alkaline medium. The prepared film samples were subjected to X-ray
diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), mechanical characterization and scanning electron microscope
(SEM). Significant changes in the tensile properties were observed depending on the different chemical constituents of the
films. The presence of clay and crosslinking with epichlorohydrin were both found to have considerable effect on the morphology
and mechanical property of the films. The SEM investigations, XRD analysis and FTIR studies revealed the interaction between
the various chemical components of the films. 相似文献
565.
Rabbany Md Ghulam Mehmood Yasir Hoque Fazlul Sarker Tanwne Hossain Kh Zulfikar Khan Arshad Ahmad Hossain Mohammad Shakhawat Roy Rana Luo Jianchao 《Environmental science and pollution research international》2022,29(1):444-456
Environmental Science and Pollution Research - This study analyzes the effects of credit constraints on technical efficiency of Boro rice growers in the district of Pabna in Bangladesh. Using a... 相似文献
566.
Rahman Md. Mominur Islam Md. Rezaul Shohag Sheikh Hossain Md. Emon Shah Muddaser shuvo Shakil khan Khan Hosneara Chowdhury Md. Arifur Rahman Bulbul Israt Jahan Hossain Md. Sarowar Sultana Sharifa Ahmed Muniruddin Akhtar Muhammad Furqan Saleem Ammara Rahman Md. Habibur 《Environmental science and pollution research international》2022,29(31):46551-46551
Environmental Science and Pollution Research - 相似文献
567.
Laura K. Blamey Éva E. Plagányi Trevor Hutton Roy A. Deng Judy Upston Annie Jarrett 《Conservation biology》2022,36(3):e13864
Short-lived, fast-growing species that contribute greatly to global capture fisheries are sensitive to fluctuations in the environment. Uncertainties in exact stock–environment relationships have meant that environmental variability and extremes have been difficult to integrate directly into fisheries management. We applied a management strategy evaluation approach for one of Australia's large prawn stocks to test the robustness of harvest control rules to environmental variability. The model ensemble included coupled environmental-population models and an alternative catchability scenario fitted to historical catch per unit effort data. We compared the efficacy of alternative management actions to conserve marine resources under a variable environment while accounting for fisher livelihoods. Model fits to catch per unit effort were reasonably good and similar across operating models (OMs). For models that were coupled to the environment, environmental parameters for El Niño years were estimated with good associated precision, and OM3 had a lower AIC score (77.61) than the base model (OM1, 80.39), whereas OM2 (AIC 82.41) had a similar AIC score, suggesting the OMs were all plausible model alternatives. Our model testing resulted in a plausible subset of management options, and stakeholders selected a permanent closure of the first fishing season based on overall performance of this option; ability to reduce the risk of fishery closure and stock collapse; robustness to uncertainties; and ease of implementation. Our simulation approach enabled the selection of an optimal yet pragmatic solution for addressing economic and conservation objectives under a variable environment with extreme events. 相似文献
568.
Mohanty Trupti Rani Tiwari Nitish Kumar Kumari Suman Ray Archisman Manna Ranjan Kumar Bayen Supriti Roy Shreya Das Gupta Subhadeep Ramteke Mitesh Hiradas Swain Himanshu Sekhar Bhor Manisha Das Basanta Kumar 《Environmental science and pollution research international》2022,29(25):37498-37512
Environmental Science and Pollution Research - Aulacoseira granulata (Ehrenberg) Simonsen 1979 are considered as the eco-variable species which varies in density and diversity along with their... 相似文献
569.
Lahiri Sandip Kumar Chowdhury Somnath Hens Abhiram Ghanta Kartik Chandra 《Environmental science and pollution research international》2022,29(14):20035-20047
Environmental Science and Pollution Research - The present work emphasizes the development of a generic methodology that addresses the core issue of any running chemical plant, i.e., how to... 相似文献
570.
Chowdhury Puja Mukhopadhyay Bhabani Prasad Nayak Siperna Bera Amit 《Environment, Development and Sustainability》2022,24(9):11320-11347
Environment, Development and Sustainability - Purulia is a hard rock terrain where water scarcity as well as water quality degradation has been a major threat for the past few decades. The prolong... 相似文献