34 resultados para Robinia pseudoacacia


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Although tannin-rich forages are known to increase protein uptake and to reduce gastrointestinal nematode infections in grazing ruminants, most published research involves forages with condensed tannins (CT), while published literature lacks information on the anthelmintic capacity, nutritional benefits, and antioxidant capacity of alternative forages containing hydrolyzable tannins (HT). We evaluated the anthelmintic activity and the antioxidant capacity of plant extracts containing either mostly CT, mostly HT, or both CT and HT. Extracts were prepared with 70% acetone, lyophilized, redissolved to doses ranging from 1.0mg/mL to 25mg/mL, and tested against adult Caenorhabditis elegans as a test model. The extract concentrations that killed 50% (LC50) or 90% (LC90) of the nematodes in 24h were determined and compared to the veterinary anthelmintic levamisole (8mg/mL). Extracts were quantified for CT by the acid butanol assay, for HT (based on gallic acid and ellagic acid) by high-performance liquid chromatography (HPLC) and total phenolics, and for their antioxidant activity by the oxygen radical absorbance capacity (ORAC) assay. Extracts with mostly CT were Lespedeza cuneata, Salix X sepulcralis, and Robinia pseudoacacia. Extracts rich in HT were Acer rubrum, Rosa multiflora, and Quercus alba, while Rhus typhina had both HT and CT. The extracts with the lowest LC50 and LC90 concentrations, respectively, in the C. elegans assay were Q. alba (0.75 and 1.06mg/mL), R. typhina collected in 2007 (0.65 and 2.74mg/mL), A. rubrum (1.03 and 5.54mg/mL), and R. multiflora (2.14 and 8.70mg/mL). At the doses of 20 and 25mg/mL, HT-rich, or both CT- and HT-rich, extracts were significantly more lethal to adult C. elegans than extracts containing only CT. All extracts were high in antioxidant capacity, with ORAC values ranging from 1800μmoles to 4651μmoles of trolox equivalents/g, but ORAC did not correlate with anthelmintic activity. The total phenolics test had a positive and highly significant (r=0.826, p≤0.01) correlation with total hydrolyzable tannins. Plants used in this research are naturalized to the Appalachian edaphoclimatic conditions, but occur in temperate climate areas worldwide. They represent a rich, renewable, and unexplored source of tannins and antioxidants for grazing ruminants, whereas conventional CT-rich forages, such as L. cuneata, may be hard to establish and adapt to areas with temperate climate. Due to their high in vitro anthelmintic activity, antioxidant capacity, and their adaptability to non-arable lands, Q. alba, R. typhina, A. rubrum, and R. multiflora have a high potential to improve the health of grazing animals and must have their anthelmintic effects confirmed in vivo in both sheep and goats. © 2012.

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应用WinEPIC模型模拟研究了1957~2001年期间黄土高原半湿润区长武和半干旱区延安不同密度刺槐(Robinia pseudoacia)林地水分生产力演变规律和深层土壤干燥化效应。结果:(1)长武和延安高密度(6000株/hm2)、中高密度(4500株/hm2)、中低密度(3000株/hm2)和低密度(1500株/hm2)等4种处理刺槐林地逐年生物量模拟值均呈现快速增加、达到最大值后又逐年波动性降低的变化趋势,林地密度越高早期逐年生物量越高,后期逐年生物量差异缩小,两地均以低密度处理逐年生物量平均值和累积生物量模拟值最高;(2)4种密度处理45年生刺槐林地年均耗水量值基本相等,长武和延安分别为603mm和566mm,但生长前期年耗水量明显高于后期,并高于同期年降水量,林地密度越高前期耗水量越高,中期以后各密度处理耗水量基本接近且波动趋势基本一致,林地密度越高干旱胁迫程度越重;(3)模拟生长初期,4种密度处理刺槐林地0~10m土层逐月土壤有效含水量均呈现强烈的波动性降低趋势,长武各密度处理刺槐林地分别在7~23年生、延安分别在7~17年生之后逐月土壤有效含水量均在0~200mm较低水平上随降水量变化而波动..

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The results obtained in germination test with seeds of "black locust" (Robinia Pseudo Acacia L) previously treated with sulphuric acid concentrated (d. 1.84) are given. Those test were made in order to get a good germination considering the water tight seed coat that those seeds have in a great percentage. The seeds were soaked in the solution for some minutes; the 180 and 210 minutes soaking (90 and 86.5 % respectively) gave the highest percentage and the fasted process of germination, which were higher than those obtained as efective by other researches. The test made would constitute another evidence of the effect of the locality of production upon the degree of water tightness of the Black locust seeds. The author suggests that the previous treatments of the seeds, the rusticity and quick growing of this species and the furrow system of irrigation so common in the zone will enable, perhaps with success the stablishment of woods of this valuable forestal species, by direct seeding.

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以延安、安塞、吴旗的人工刺槐林、柠条林为研究对象,选取同一地区的自然恢复草地和坡耕地为对照,通过对5个表征土壤抗蚀性的指标即>0.25 mm水稳性团粒含量、>0.5 mm水稳性团粒含量、平均重量直径、团聚状况和团聚度的比较分析,对人工刺槐林、人工柠条林相对于自然恢复草地和坡耕地改善土壤抗蚀性的效果进行了评价,同时分析了不同林龄人工林土壤抗蚀性的变化。研究表明,人工林地相对于坡耕地,显著提高了土壤抗蚀性,但不及自然恢复草地,尤其在安塞和吴旗表现更明显;随着林龄的增长,人工林地土壤抗蚀性能增强,并趋于稳定。并通过对样地的聚类分析,也得出与上述相似的结果。综合分析表明,封禁条件下的植被自然恢复是黄土丘陵沟壑区比较适宜的植被恢复方式和控制土壤侵蚀的有效措施。

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土壤碳库管理指数是表征土壤碳变化的重要量化指标,研究黄土丘陵区人工刺槐林土壤活性有机碳与碳库管理指数的变化过程对认识该地区生态恢复过程中土壤质量的演变及其效果评价具有重要意义。【方法】采用时空互代法,以典型侵蚀环境纸坊沟流域生态恢复过程中不同年限的人工刺槐林为研究对象,选取坡耕地和天然侧柏林为参照,分析了植被恢复过程中土壤有机碳(TOC)、活性有机碳(LOC)、非活性有机碳(NLOC)及碳库管理指数(CPMI)的演变特征,并运用相关和回归分析方法对生态恢复过程中碳库各组分和恢复年限进行拟合。【结果】营造刺槐林可以显著增加土壤碳库各组分含量,并随恢复年限呈显著线性关系,50a时TOC、LOC、NLOC和碳库指数(CPI)分别较坡耕地增加271%、174%、467%和271%,其中NLOC增加速率略高于LOC,表明植被恢复增加的土壤碳素绝大多数以非活性形态贮存起来,而为了满足生物生长所必须的活性物质来源,土壤碳库必须维持一定的活度状态来满足碳素的动态转化平衡,碳库管理指数在营造刺槐林初期显著降低,随后先增加后降低,与刺槐林生长特性密切相关;但与天然林相比差距仍然较大,恢复50a时TOC、LOC和NLOC仅...

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本文系统研究了沈阳城市森林的布局与结构、城市森林功能、城市森林病虫害发生与树木健康状况和城市自然资源与社会经济状况等指标对沈阳城市森林生态系统健康与管理的影响。同时一,采用2种生态系统健康评价方法对沈阳城市森林生态系统健康状况进行了评价,并提出了沈阳城市森林生态系统健康管理的对策。研究结果如下:1、截至2004年末,沈阳城市森林植被覆盖率已经达到35%,城市森林林地分布基本合理,但需要进一步加强道路林地、居住区林地和城郊大面积生态林建设。2、沈阳城市森林以乔木为主,乔灌株数比为1.7:1,乔灌的覆盖度比约为7:1。3、沈阳城市森林不同类型林地中植物组成不同。公园林地中有74个属,137个种(变种);庭院林地中有53个属,104个种(变种);居住区林地中有45个属,81个种(变种);道路林地中有43个属,94个种(变种);运河风景林地中有75个属,142个种(变种);棋盘山风景林地中有48个属,118个种(变种)。4、公园林地、庭院林地、居住区林地、道路林地和运河风景林地的Shannon一Wiener多样性指数分别为2.78、3.05、3.15、3.18和3.18,均匀度指数分别为0.56、0.66、0.72、0.70和0.64。除了棋盘山风景林地外,沈阳城市森林中栽植总量超过乔木总量5%的乔木树种有7个属,分别为李、柳树、杨树、桧柏、榆树、槐树和银杏,7种树木总量达到了全部乔木总量的82.09%;栽植总量超过灌木总量5%的灌木树种也有7个属,分别为水腊、丁香、李属,小聚、玫瑰、忍冬和连翘,7个属灌木总量达到了全部灌木总量的87.92%。5、公园林地、庭院林地、道路林地和防护林地中OBH<20cm、20cm<DBH<60cm和DBH>60cm树木的比例分别为:57.9%、40.0%、2.1%,49.2%、47.8%、3.0%,65.3%、33.1%、1.6%和64.6%、34.9%、0.5%,表明沈阳城市森林树木的规格总体上偏小。6、经样方调查和CITYgreen模型计算,沈阳城市森林的生态效益约2.0亿USD/yr.。公园林地、庭院林地和风景林地的景观指标相对较高;道路林地和居住区林地的景观效果一般;防护林地的景观效果较差。7、目前已经发现的沈阳城市森林病害约600余种,虫害约700余种,其中杨树主要病虫害39种,柳树的主要病虫害有33种,榆树和槐树的主要病虫害均为,1种。杨柳树腐烂病、光肩星天牛、天幕毛虫、桃红颈天牛和美国白蛾等是近10年来沈阳城市森林中普遍发生和造成严重危害的主要病虫害。沈阳城市森林主要树木的平均健康指数为2.68,处于一般健康状态。8、沈阳城市森林的土壤和水资源状况均不利于树木的健康生长,沈阳的社会经济发展也有待于进一步提高。9、经过生物指示物法(光肩星天牛为生物指示物)、专家权重法、公众问卷调查和对比研究,沈阳城市森林生态系统总体上处于亚健康状态。10、通过对沈阳城市森林资源、管理状况的调查研究和健康状况的评价,本文提出了沈阳城市森林生态系统健康管理的对策,包括合理规划沈阳城市森林林地布局,增加道路林地、居住区林地和城郊林地的面积和植被覆盖率;调整树木种类组成,避免单一或少数树种的大量栽植,提高生物多样性水平;保护大树和古树;增加城市森林管理资金的投入;应用先进技术,采取科学的病虫害防治和植物养护方法,促进树木的健康生长等。This project systematically studied the urban forest ecosystem health and management in Shenyang. The study explored factors, such as urban forest structure, distribution, pests, aesthetic value, ecological benefit, natural resources and socieo-economic status, that affecting the urban forest ecosystem health and management. Two methods were used to evaluate the ecosystem health. This project also proposed Shenyang's urban forest ecosystem health management strategies. The research results can be summarized as follows: 1. As of the end of 2004, urban forest coverage in Shenyang is about 35%, and is in relatively even patch distribution pattern. However, the street trees and roadside forest patches, residential block forest patches should be enhanced. 2. Trees are the major component of the Shenyang s urban forest, followed by shrubs. The quantity ratio of tree to shrub is about 1.7:1, and the coverage ratio of trees to shrub is about 7:1. 3. Species composition varies by location. There are 74 genera, 137 species (including varieties) in the public parks; 53 genera, 104 species (and var.) in the green spaces of the institution (including school), factory, and company; 45 genera, 81 species (var.) in residential blocks; 43 genera, 94 species (var.) in streets and roadside forest patches; 75 genera, 142 species (var.) in the Canal landscape forest patches; 48 genera, 118 species (var.) in the Qipan Mountain recreation forest. 4. The Shannon-Woener indices varies in parks, in institution, factory, and company yards, in streets and roadside forest patches, in residential blocks.there are 2.78, 3.05, 3.18, 3.15, 3.18, respectively; and the evenness indices are 0.56, 0.66, 0.70, 0.72, 0.64, respectively. Besides the Qipan Mountain forest patches, trees of 7 genera, Prunus spp., Salix spp., Populus spp., Sabina spp., Ulmus spp., Robinia spp. and Ginkgo biloba are of more than 5% the total urban trees, respectively. In fact, trees from these 7 genera are about 82% of all trees in Shenyang's urban forests. In terms of shrubs, species of 7 genera, Ligustrum spp., Syringa spp., Prunus spp., Berberis spp., Rosa spp., Lonicera spp., and Forsythia spp. are more than 5% the total urban shrubs, respectively. 88% of all the shrubs in Shenyang s urban forest are from these 7 genera. 5. The diameter class of DBH<20cm, 20cm60cm of trees in parks, in institution, factory, and company yards, in in streets and roadside forests, and in protective forests are 57.9%, 40.0%, 2.1%; 49.2%, 47.8%, 3.0%; 65.3%, 33.1%, 1.6%; and 64.6%, 34.9%, 0.5%, respectively. The result indicated that the DBH is relatively small in Shenyang s urban forests. 6. Using random plots sampling and CITYgreen model calculation, the ecological benefit of Shenyang's urban is about 0.2 billion US dollars per year. The aesthetic value of parks, institution and company yards, and scenary forest patches is relative high; however, the aesthetic value of protective forest patches is low. 7. There are more than 600 types of diseases and more than 700 kinds of insects in Shenyang's urban forest. Among them, Populus spp., Salix spp., Ulmus spp. and Robinia spp., are attached mainly by 39, 33, 11, and 11, difference types of pests respectively. The rot disease of the Populus spp. and Salix spp., and the insects such as, Anoplophora glabripennis, Malacosoma neustria, Aromia bungii, and Hyphantria cunea are major pests in Shenyang s urban forest for the past 10 years. The trees health condition is relatively poor by having the average health index of 2.68 for major species. 8. The urban soil and water resource are not favorable to tree's growth in Shenyang, and so is the socieo-economic status. 9. Through using bio-indicator, professional and public evaluation, and comparision with other urban forests, it can be concluded that the status of Shenyang s urban forest is not very healthy in general. 10. To improve the urban forest ecosystem health in Shenyang, a better urban forest design need to be implemented to enhance the area and vegetation coverage of the street and roadside forests, the residential block forests, and the surburb forest Species biodiversity need to be enhanced by adjust the species composition of urban forest trees to reduce the single or several tree species populations and to plant more varieties. A better fundings for urban forest health management need to be budgeted. Advanced technologies in tree care and scientific measures to control pests need to be adopted to prove better care for plants and to keep trees grow healthfully.

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研究黄土高原沟壑区不同树种幼林的水土保持效益及其适应性。【方法】以草地为对照,对黄土高原沟壑区刺槐、油松、沙棘、侧柏纯林及其混交林径流小区的产流产沙情况、土壤水分状况及各树种的生理特性进行了分析。【结果】造林初期,各树种及其不同造林方式的水土保持效益均比较差,处于水土保持功能低下阶段,土壤侵蚀的差异主要是由植被的不同覆盖度引起的,二者呈二次多项式关系;回归分析表明,当覆盖度达53%时土壤侵蚀较为轻微。草地和各树种林下0~250 cm土层土壤水分变化较大,其中以刺槐消耗土壤水分最多,其次是侧柏,油松、沙棘和草地之间差异不明显;刺槐纯林与其混交林下土壤水分的差异比较明显,而其他树种不同造林方式下的土壤水分无明显差异。各树种叶片的水分利用效率表现为侧柏>油松≈沙棘>刺槐,油松与沙棘混交造林后两者的水分利用效率都有显著提高;各树种叶片的蒸腾速率表现为刺槐≈沙棘>油松>侧柏,沙棘与油松或刺槐混交后,油松与刺槐的蒸腾速率均有所降低,而沙棘变化不显著。【结论】综合考虑树种的水保效益及其适应性可以发现,沙棘与油松混交可能是黄土高原沟壑区较为适宜的一种造林方式。

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通过对油松(Pinus tabulaeformis Carr.)、刺槐(Robima pseudoacacia L.)混交林、油松纯林及刺槐纯林多种土壤微生物种群数量、酶活性及其季节变化的对比分析。结果表明,油松刺槐混交显著改善了林地土壤生物学特性,土壤细菌、真菌和放线菌以及固氮菌、磷细菌、钾细菌的种群数量较纯林均明显增多,土壤质量明显改善。油松刺槐混交提高了土壤过氧化氢酶、脲酶和磷酸酶活性。此外,研究还显示,混交林土壤生物学特性的改变与生长季土壤含水量密切相关。

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Introducción: la medición de la densidad mineral ósea en el fémur y columna lumbar es considerada la prueba de oro para el diagnóstico de osteoporosis en mujeres postmenopáusicas, sin tener suficiente evidencia de la utilidad al medir de manera individual o simultanea el radio 33 con este mismo propósito. Metodología Se realizó un estudio de pruebas diagnósticas, valorando concordancia anidada para determinar el valor diagnóstico del radio 33 comparado con los resultados por dual fémur y columna, actualmente patrón de oro el en diagnóstico. Se incluyeron mujeres mayores de 50 años entre el periodo de 2008 y 2011. Resultados Se incluyeron 3241 osteodensitometrias de pacientes femeninas con columna AP, dual fémur, radio ultradistal y radio 33. Tomando como estándar de oro la medición en columna y/o femur, el radio-33 obtuvo una sensibilidad de 95.5% y especificidad de 91% (p= 0,000) para osteoporosis, y una sensibilidad de 76.5% y especificidad de 54.9% p=0,000 para el diagnóstico de osteopenia. El radio 33 permite diagnosticar un 35% adicional de casos que no son captados con la medición en fémur y columna lumbar. Discusión La osteodensitometría en los sitios usados comúnmente, predice únicamente el 40% del riesgo de fractura (1). Si se incluye la medición de radio 33, la sensibilidad de la osteodensitometría sube en un 35.66% adicional, logrando detectar más pacientes con este riesgo y generando un impacto en la oportunidad del tratamiento y quizás reducción en la morbi-mortalidad secundaria a fracturas en esta población susceptible.

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Southern China, especially Yunnan, has undergone high tectonic activity caused by the uplift of Himalayan Mountains during the Neogene, which led to a fast changing palaeogeography. Previous study shows that Southern China has been influenced by the Asian Monsoon since at least the Early Miocene. However, it is yet not well understood how intense the Miocene monsoon system was. In the present study, 63 fossil floras of 16 localities from Southern China are compiled and evaluated for obtaining available information concerning floristic composition, stratigraphic age, sedimentology, etc. Based on such reliable information, selected mega- and micro-floras have been analysed with the coexistence approach to obtain quantitative palaeoclimate data. Visualization of climate results in maps shows a distinct spatial differentiation in Southern China during the Miocene. Higher seasonalities of temperature and precipitation occur in the north and south parts of Southern China, respectively. During the Miocene, most regions of Southern China and Europe were both warm and humid. Central Eurasia was likely to be an arid center, which gradually spread westward and eastward. Our data provide information about Miocene climate patterns in Southern China and about the evolution of these patterns throughout the Miocene, and is also crucial to unravel and understand the climatic signals of global cooling and tectonic uplift.

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Neogene climates and vegetation history of western Yunnan are reconstructed on the basis of known fossil plants using the Coexistence Approach (CA) and Leaf Margin Analysis (LMA). Four Neogene leaf floras from Tengchong, Jianchuan and Eryuan in southwestern China are analyzed by the CA, and the paleoclimatic data of one Miocene carpoflora from Longling and three Pliocene palynofloras from Longling, Yangyi and Eryuan are used for comparison. The Miocene vegetation of the whole of West Yunnan is subtropical evergreen broad-leaved forest, and a similar mean annual precipitation is inferred for Tengchong, Longling and Jianchuan. However, by the Late Pliocene a large difference in vegetation occurred between the two slopes of Gaoligong Mountain, western Yunnan. The region of Tengchong retained a subtropical evergreen broad-leaved forest vegetation, whereas in Yangyi and Eryuan a vertical vegetation zonation had developed, which consists, in ascending order, of humid evergreen broad-leaved, needle and broad-leaved mixed evergreen, and coniferous forests. Distinctively, the Late Pliocene vegetational patterns of West Yunnan were already very similar to those of the present, and the Pliocene mean annual precipitation in Tengchong was markedly higher than that of Yangyi and Eryuan. Considering that the overall vegetation of West Yunnan and the precipitation at Yangyi and Eryuan have undergone no distinct change since the Late Pliocene, we conclude that the Hengduan Mountains on the northern boundary of West Yunnan must have arisen after the Miocene and approached their highest elevation before the Late Pliocene. Furthermore, the fact of the eastern portion of the Tibetan Plateau underwent a slight uplift after the Late Pliocene is also supported.