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61.
Plain tales from the grasslands: extraction, value and utilization of biomass in Royal BardiaNational Park, Nepal 总被引:1,自引:0,他引:1
Katrina Brown 《Biodiversity and Conservation》1997,6(1):59-74
Royal Bardia National Park in Southern Nepal contains a number of internationally endangered wildlife species, and a mix of habitats, including areas of grassland known as phantas. The conservation and current use of these areas is briefly described, including the extraction of grass from inside the National Park by local people living in adjacent villages. The products collected fulfil a range of human needs, both practical and ceremonial. The study attempts to quantify the annual offtake in both material and monetary terms, and comments on the sustainability of the practice. Alternative sources of roofing materials are apparently outside the scope of poorer households. The use of these materials has particular significance given the initiation of a Parks and People Project to implement a Buffer Zone around the National Park and effectively to link conservation and development needs. 相似文献
62.
土壤呼吸的影响因素及全球尺度下温度的影响 总被引:188,自引:19,他引:169
土壤呼吸是指土壤释放CO2的过程,主要由土壤微生物和根系产生。作为一个复杂的生态学过程,土壤呼吸在受到植被,微生物等生物因素影响的同时,也受到了温度,湿度、pH值等环境因素的作用,并且随着人类影响的增强,人为因素的作用也越来越大。根据已有工作,讨论了影响土壤呼吸的主要影响因素及其相互关系,分析了全球范围内湿润地区森林植被的土壤呼吸与纬度的关系以及土壤呼吸与年均温的关系,得出了全球范围的Q10值为1 相似文献
63.
T. G. Nolen P. M. Johnson C. E. Kicklighter T. Capo 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1995,176(2):239-254
1. | Aplysia californica incorporates toxins and pigments from its red seaweed diet into its body and ink, purportedly as a defense against predation. We tested ink's potential defensive function by assessing the survival of green seaweed-fed (red algal toxin deprived) snails in encounters with a natural predator, the sea anemone Anthopleura xanthogrammica. |
2. | Red seaweed-fed Aplysia secreted copious amounts of ink when ensnared in anemone tentacles. A similar amount of ink applied to inkless (green-fed) snails as they were engulfed by an anemone enhanced their survival [71% survived (ink) vs 7% (seawater control)]. Ink caused anemones to reject whitefish (a familiar food) [50% rejected (ink) vs 10% (seawater control)], triggering gastrovascular eversions, which ejected ink as well as prey from their digestive cavities. Snails with only a passive chemical defense (algal toxins, no ink) escaped less often than snails with only an active chemical defense (ink, no red algal toxins) (20% survived vs 71%) and about as often as red algal toxin deprived snails (20% vs 12%). Snails avoided ink by chemical orientation, thus avoiding potential sites of ongoing predation. |
3. | The survival value of ink and the snail's aversion to it supports ink's proposed anti-predator function. |
64.
Summary This field study was undertaken to determine the effect of inoculation withGlomus mosseae on N2 fixation and P uptake by soybean. The inoculation withGlomus mosseae was achieved using a new type of inoculant, alginate-entrapped (AE) endomycorrhizal fungus. N2 fixation was assessed using the A value method. In P-fertilized plots, inoculation with AEGlomus mosseae increased the harvest index based on dry weight (+20%) and N content of seeds (+17%), the A value (+31%) and %N derived from fixation (+75%). Inoculation with AEGlomus mosseae decreased the coefficient of variation for the A value and for the dry weights of the different plant parts. 相似文献
65.
经济开发区生态规划与建设研究 总被引:4,自引:0,他引:4
生态规划和建设是协调经济发展和生态环境关系,创造和谐的人工化环境的调控对策。木文研究了沈阳开发区生态规划和建设的理论、方法,着重探讨了开发区经济、环境协调发展的途径:1)选择理想的协调发展优化方案,2)控制发展热电生产,发展集中供热和低能耗高技术产业,3)节约水资源,提高水循环利用率,4)在生态学原理指导下进行生态管理。 相似文献
66.
67.
Summary The chemical equilibrium and E value for Zn was calculated in 9 soils of Haryana (India) which represented mainly entisol
and inceptisols. The rate of isotopic exchange between65Zn and native soil Zn was quite rapid and radioactivity reduced to about 0.2 per cent of initial activity after 3 days but
total Zn concentration in soil solution did not decrease. In 5 out of 9 soils equilibrium was established in 2 to 3 days.
In typic ustochrepts having high clay content (3,4) equilibrium was attained in two days. In typic udipsamments (2), typic
camborthids (8) and aquic vertic ustichrepts (9) it took 3 days to set equilibrium. Typic ustochrepts (5) took 5 days for
equilibrium whereas typic ustipssaments (6) and typic camborthids of high O.C. did not attain equilibrium even in 7 days.
This indicated that the chemistry and availability of Zn in soil would depend on soil types.
When ZnE was estimated by applying activity after equilibrium with carrier Zn and by applying activity with carrier Zn before equilibrium
was set, there was no agreement in ZnE in two methods. Increasing ZnE with increasing Zn dose was observed by both methods only in alkaline typic ustochrept (4). In some soils higher E values
than added amounts were observed, whereas, in soil 8 negative E values were obtained. The E values become erratic and are
over estimated where complex reactions take place due to high pH, high O.C. and high complex forming elements. 相似文献
68.
Craig S. Tucker 《Hydrobiologia》1981,85(1):73-76
Eichhornia crassipes (Mart.) Solms, Pistia stratiotes (L.), and Lemna minor (L.) were cultured at four different densities each and analyzed for cell-wall fraction, crude protein, total available carbohydrate and ash. Cell-wall fraction increased and crude protein content decreased as density increased in Eichhornia and Pistia cultures. The cell-wall and crude protein content of Lemna did not change with increasing culture density. Differences in the trends of cell-wall and crude protein content of the three plants at increasing culture densities appear to be related to differences in growth form. There was no difference in the total available carbohydrate or ash content of the three species at different culture densities. 相似文献
69.
《Saudi Journal of Biological Sciences》2018,25(2):320-325
Honey is a natural food item produced by honey bees. Ancient civilizations considered honey as a God gifted prestigious product. Therefore, a huge literature is available regarding honey importance in almost all religions. Physically, honey is a viscous and jelly material having no specific color. Chemically, honey is a complex blend of many organic and inorganic compounds such as sugars, proteins, organic acids, pigments, minerals, and many other elements. Honey use as a therapeutic agent is as old as human civilization itself. Prior to the appearance of present day drugs, honey was conventionally used for treating many diseases. At this instant, the modern research has proven the medicinal importance of honey. It has broad spectrum anti-biotic, anti-viral and anti-fungal activities. Honey prevents and kills microbes through different mechanism such as elevated pH and enzyme activities. Till now, no synthetic compound that works as anti-bacterial, anti-viral and anti-fungal drugs has been reported in honey yet it works against bacteria, viruses and fungi while no anti-protozoal activity has been reported. Potent anti-oxidant, anti-inflammatory and anti-cancerous activities of honey have been reported. Honey is not only significant as anti-inflammatory drug that relieve inflammation but also protect liver by degenerative effects of synthetic anti-inflammatory drugs. This article reviews physico-chemical properties, traditional use of honey as medicine and mechanism of action of honey in the light of modern scientific medicinal knowledge. 相似文献
70.