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111.
本研究是在内蒙古白音锡勒种畜场自然放牧条件下进行的,按季节及自然气温分为四期,进行物质消化代谢及气体能量代谢试验,同时监测环境温度、湿度、风速及日照时数等气象指标。采用灰色关联度法分析探讨在放牧条件下,牧草营养因素和外界环境因素对育成公羊能量及营养物质代谢的影响。 相似文献
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Gyungsoo Cha 《Journal of Forest Research》1997,2(3):147-152
Change in potential natural vegetation (PNV) distribution associated with climate change due to the doubling atmospheric carbon
dioxide (2×CO2) was estimated with a global natural vegetation mapping system based on the modified Kira scheme to the globe and the continents.
With an input of widely-distributed global climate data, the system interpolates data onto a 1° latitude by 1° longitude grid
over the globe, generates estimates of vegetation type, and produces a composite PNV map. The input climate data corresponding
to the 1×CO2 and 2×CO2 consists of observations prior to AD 1958 at 2,001 weather stations worldwide and the 2×CO2 simulation output from the Japan Meteorological Research Institue's General Circulation Model, respectively. As a result
of the simulated global warming, the vegetation zones expanded mostly from the tropics toward the poles. PNV area changed
by 6.98 billion (G) ha of the total land area (15.04 Gha) and potential forest area corresponding to the closed forest and
open forest (woodland) reached 9.74 Gha with the increase of 1.29 Gha. The potential forest area in Europe had obvious advantages
to the climate change accompanied with the increase of actual forest area. Although the actual forest area has decreased in
North America and Asia, the potential forest area in these continents also benefitted from the climate change. In the end,
the remaining continents tended to bear the brunt of the climate change. 相似文献
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We applied dendrochronology (tree‐ring) methods to develop multidecadal growth chronologies from the increment widths of yelloweye rockfish (Sebastes ruberrimus) otoliths. Chronologies were developed for the central California coast, a site just north of Vancouver Island, British Columbia, and at Bowie Seamount west of the Queen Charlotte Islands, British Columbia. At each site, synchronous growth patterns were matched among otoliths via the process of cross‐dating, ensuring that the correct calendar year was assigned to all increments. Each time series of growth‐increment measurements was divided by the values predicted by a best‐fit negative exponential function, thereby removing age‐related trends. These detrended time series were averaged into a master chronology for each site, and chronologies were correlated with monthly averages of sea surface temperatures, upwelling, the Northern Oscillation Index, and the Pacific Decadal Oscillation. The two northern growth chronologies positively correlated with indices of warm ocean conditions, especially from the prior summer through the spring of the current year. During the same period, the California chronology positively correlated with indices of cool ocean conditions, indicating an opposing productivity regime for yelloweye rockfish between the California Current and the Gulf of Alaska. Overall, this study demonstrates how tree‐ring techniques can be applied to quickly develop annually resolved chronologies and establish climate–growth relationships across various temporal and spatial scales. 相似文献
115.
水稻拔节期和抽穗期低温对稻米品质影响 总被引:1,自引:0,他引:1
【目的】为了探讨低温冷害对水稻品质的影响,以便为气候变化背景下辽宁地区水稻的高效栽培和品质认证提供理论依据。【方法】以水稻90-35为供试品种,分别于拔节期和抽穗期通过TRP-1000D型人工智能气候箱进行不同低温处理(比外界低5℃和低3℃,均持续5 d),以正常栽培管理作对照,5个处理,分别记为CK、A1、A2、B1、B2,分析拔节期和抽穗期不同等级低温胁迫处理对水稻的营养品质、研磨品质和外观品质的影响。【结果】低温胁迫下90-35水稻的蛋白质含量、直链淀粉含量较CK显著增加,处理A1、A2、B1、B2的蛋白质含量分别比CK增加3.45%、1.15%、6.90%、8.05%,除处理B1外直链淀粉含量分别比CK增加1.75%、0.44%、0.44%;脂肪酸含量和精米率较CK显著减少,处理A1、A2、B1、B2的脂肪酸含量分别比CK减少17.75%、7.5%、25%、11%,精米率分别比CK减少2.1%、6.95%、0.22%、7.5%。拔节期低温胁迫下糙米率和垩白粒率显著减少,处理A1、A2的糙米率分别比CK减少0.73%、1.09%,垩白粒率分别比CK减少33.3%、22.2%;抽雄期低温胁迫下糙米率和垩白粒率显著增加,处理B1、B2的的糙米率分别比CK增加0.6%、3.02%,垩白粒率分别比CK增加255.6%、133.3%,即低温胁迫使其营养品质和研磨品质中的精米率受到负面影响,而拔节期适当低温胁迫处理对其研磨品质中的糙米率和外观品质有益。【结论】水稻90-35在不同生育时期经受不同低温胁迫处理后,水稻的营养品质、研磨品质和外观品质均受到不同程度的影响。 相似文献
116.
太行山丘陵区气候条件与牧草生长发育关系研究 总被引:4,自引:0,他引:4
对在太行山低山丘陵区引种的29种牧草中能正常生长的11种牧草的生长发育与气象条件关系分析的基础上,认为豆科牧草的沙打旺、扁豌豆适应性较差,不适于在此地区发展,红豆草也一定程度地表现出较差的适应性。表现最好的为禾本科牧草和豆科牧草的紫花苜蓿、其他苜蓿、黄花草木樨等。 相似文献
117.
《Land Degradation \u0026amp; Development》2017,28(7):2207-2221
Relatively few studies have so far investigated the hydrological impacts of urbanization in Mediterranean catchments, and particularly in peri‐urban catchments experiencing relatively rapid and large changes in their land‐use mosaic. This study uses data‐based model simulations to investigate such impacts, with the Ribeira dos Covões catchment in Portugal as a concrete Mediterranean peri‐urban catchment example. We distinguish the impacts of urbanization from those of climatic change on the water flux partitioning and connectivity in the catchment over the period 1958–2013. Decrease in precipitation over this period has primarily driven decreases in annual runoff and actual evapotranspiration, while the urbanization development has primarily changed the relative flux partitioning and connectivity pattern in the catchment. The relative contribution of overland flow to annual and seasonal runoff has increased, keeping the absolute overland flow more or less intact, while the baseflow contribution to the stream network has decreased. Methodologically, the present simulation approach provides a relevant means for distinguishing main drivers of change in hydrological flux partitioning and connectivity under concurrent urbanization and climatic changes. © 2017 The Authors. Land Degradation & Development Published by John Wiley & Sons Ltd. 相似文献
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