温度对玉米生长和发育综合影响的评价模型     

孙玉亭  孙孟梅  姜丽霞 《黑龙江气象》1998,(3)

根据玉米分期播种发育期观测资料和干物质累积及籽粒干物质累积资料,求出玉米发育期的热量指标,在此基础上建立光合作用模型,温度、水分对光和作用影响模型和呼吸及物质转运模型;建立温度对玉米发育进程和物质积累的综合评价模型,并用该模型评价发育进程中温度对发育和物质积累的影响,以及对成熟度和产量的影响,从而为评价温度变化对作物的影响提供依据。  相似文献   

水体内藻类的生物地球化学   总被引：3，自引：0，他引：3  

王宝利  刘丛强 《矿物岩石地球化学通报》2004,23(1):79-82

藻类对水体内生命元素的转化及其分布、迁移的影响．是目前水体内藻类生物地球化学研究的重点内容。藻通过光合作用和生物矿化，控制着C、N、Si、P、S、Ca等元素在水体内的循环；驱动着C和S在水体和大气之间的交换，进而影响大气中的C和S。藻生物积累及其对环境变化的及时反馈，使藻类成为地球化学环境变化的生物指示物。本文对水体内藻类的生物地球化学进行了综述。  相似文献   

就"高山林线乔木光合作用与环境因子关系"的几个问题答罗辑先生     

刘鸿雁  谷洪涛  唐志尧  戴君虎  崔海亭 《山地学报》2004,22(2):259-260

对罗辑先生提出的商榷意见进行回复。认为，原文的数据是在天气情况正常、仪器调试正常和操作无误的情况下获得的。因此是可靠的。根据自动记录仪的观测结果，高山林线处七月份的夜间(18：00～6：00)为3．5～5℃。由于夜间温度很低。呼吸消耗也较低。高山地区的可达性很差，全面系统地研究高山林线乔木的生理活动存在诸多困难，已有的观测数据对今后继续研究是一种积累，不能说实验已经失败了。  相似文献   

棉花群体光合生产动态模拟   总被引：3，自引：1，他引：3  

董尚力  申双和  李秉柏  徐立华  张京红 《南京气象学院学报》2001,24(2):194-198

以棉花的生物学特性为基础，充分考虑棉花棉型特征，将棉株分成三层（层距为1．5个叶面积指数），逐层进行光合作用模拟，并加以综合，得出棉花群体光合产量，资料验证结果表明，在水肥等条件下适宜的情况下，本模型能较好地反映棉花光合生产特性，模拟预测棉花总生物量精度较高，可用于辅助指导大田生产管理。  相似文献   

Role of pigments on algal communities and photosynthesis   总被引：2，自引：0，他引：2  

A. Lami  P. Guilizzoni  D. Ruggiu  B. Polli  M. Simona  A. Barbieri 《Aquatic Sciences - Research Across Boundaries》1992,54(3-4):321-330

A one-year study of phytoplankton, primary production and related physical and chemical factors was made in a Swiss basin of Lake Lugano (Lago di Lugano). The chlorophylls and 12 carotenoids were analyzed with a TLC technique. The carotenoid monitoring was considered to be particularly interesting, because the role of these pigments in freshwater algae is still very poorly documented by field studies. The dependence of photosynthesis on several factors was statistically evaluated. Evidence was found of light-adaptation phenomena. The variations of photosynthetic activity and efficiency largely depended on the light regime in the few days before the field observations and on the cellular content of chlorophylls and single carotenoids, whose concentrations in their turn were closely linked with light, temperature, average cell size, and with the actual species assemblage.  相似文献   

Physiology of Laminaria     

Edward A.  Drew 《Marine Ecology》1983,4(3):227-250

Abstract. Discs of lamina tissue excised from Laminaria digitata, L. hyperborea and L. saccharina were unaffected by cutting. They photosynthesized at a constant rate for several days and increased in area and weight during prolonged bubble cultures at a rate comparable with that of plants on the shore.  相似文献   

One Dimensional Ecosystem Model Simulation of the Effects of Vertical Dilution by the Winter Mixing on the Spring Diatom Bloom     

Naoki Yoshie  Yasuhiro Yamanaka  Michio J. Kishi  Hiroaki Saito 《Journal of Oceanography》2003,59(5):563-571

A one-dimensional ecosystem model has been used to investigate the processes relevant to the spring diatom bloom which play important roles in the biogeochemical cycle in the western subarctic Pacific. The model represents the plankton dynamics and the nutrient cycles in the spring diatom bloom; its results show the importance of dilution by deep mixing in winter. It is supposed that the vertically integrated biomass of phytoplankton decreases in the winter due to the decrease of photosynthesis, because the deep mixing transports phytoplankton to a layer with a low light level. However, the observed integrated diatom biomass increases as the mixed layer deepens. This is because the decrease of concentration due to dilution by mixing causes the diatom grazed pressure to be less significant than diatom photosynthesis. In other words, the effect of dilution on the grazed rate is more significant than the effect on the photosynthesis rate because the grazed rate depends on the concentrations of both diatom and grazer, whereas the photosynthesis rate depends only diatom concentration. The average specific diatom grazed rate, defined as grazed rate divided by diatom biomass, decreases by 35% associated with the deepening, while the average specific photosynthesis rate of diatom decreases by 11%. As a result, the average specific net diatom growth rate during the deep mixing is about 70% of its maximum during the spring diatom bloom. The deep mixing significantly affects the amplitude of the spring diatom bloom not only by the supply of nutrients but also by the dilution which drastically decreases the grazed pressure. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Manganese and Iron Oxidation During Benthic Oxygenic Photosynthesis     

E.H.G. Epping  V. Schoemann  H. de Heij 《Estuarine, Coastal and Shelf Science》1998,47(6):753-767

The effect of benthic oxygenic photosynthesis on sediment-water fluxes of manganese and iron was studied for an intertidal sediment. Undisturbed sediments were incubated at an incident surface irradiance of 250 μE m⁻² s⁻¹at 26 °C. Oxygenic photosynthesis was selectively inhibited by adding [3-(3,4-dichloro)-1,1-dimethyl-urea] (DCMU). Benthic fluxes were determined experimentally from the change in manganese and iron concentrations in the overlying water, and were predicted from the pore water concentration gradients at the sediment-water interface assuming molecular diffusion as the transport mechanism. The experimental fluxes of manganese and iron in DCMU-treated cores amounted to −0·84 and −0·59 mmol m⁻²day⁻¹, respectively, and were directed from the sediment towards the overlying water. In the control cores, showing high rates of benthic oxygenic photosynthesis, the fluxes of manganese and iron were directed towards the sediment, 0·06 and 0·01 mmol m⁻²day⁻¹, respectively. Mass balances for the 0·1–0·14 cm thick oxic zone, calculated from the experimental fluxes and the predicted fluxes, suggest a minimum areal reoxidation of 0·6 mmol m⁻²day⁻¹for manganese and of 0·48 mmol m⁻²day⁻¹for iron in cores showing benthic photosynthesis. The estimated turnover times for dissolved Mn²⁺and dissolved Fe²⁺in the oxic surface layer during benthic photosynthesis were 0·8 and 0·25 h, respectively. Sediment oxygen microprofiles and the sediment pH profiles suggest that chemical precipitation and reoxidation dominates the retention of manganese and iron during benthic oxygenic photosynthesis in shallow intertidal sediments.  相似文献   

四川黄龙沟源头黄龙泉泉水及其下游溪水的水化学变化研究   总被引：8，自引：2，他引：6  

王海静  刘再华  曾成  刘香玲  孙海龙  安德军  唐淑  张清明 《地球化学》2009,38(3):307-314

用水化学仪器自动记录、现场滴定及取样室内分析等方法,对四川黄龙沟钙华景区水的物理化学动态变化特征进行了研究。结果发现,黄龙钙华的沉积主要起因于水中CO2的大量释放,造成溪流自黄龙泉泉口向下游方向水的二氧化碳分压（p（CO2））和电导率（EC）降低,pH值和方解石饱和指数（SIc）升高。但仔细分析发现,水化学的这一空间变化主要发生在SIc〈1．0时;当SIc〉1．0后,向下游方向,水化学趋于稳定。同时,黄龙沟地表融雪水和沿途泉水分别产生的稀释和浓集作用对溪流水化学的这一空间变化产生了明显的影响。此外,源头黄龙泉的水化学稳定,没有明显的日变化,而下游的池水则出现pH值、EC和SIc及p（CO2）的显著日变化,即白天p（CO2）、EC较低,而pH和SIc较高,反映了白天较快的碳酸钙沉积,其中温度和水生生物光合作用的影响可分别达到19％和81％。  相似文献   

脆弱生态带典型区域几种锦鸡儿属优势灌木的光合特征   总被引：29，自引：16，他引：13  

周海燕  张景光  龙利群  赵亮 《中国沙漠》2001,21(3):227-231

小叶锦鸡儿在原产地科尔沁沙地光合速率可达12.21μmol·m^-2·s^-1,引种至腾格里沙漠后降低了11.63倍,光合日变化曲线由"凹谷"型变为"单峰"型;毛乌素沙地中间锦鸡儿的光合速率在引种前为4.5μmol·m^-2·s^-1,引种后降低了3倍,光合日变化曲线由"双峰"型变为"单峰"型;在相同的环境条件下,柠条和中间锦鸡儿光合等特性相似,以小叶锦鸡儿光合速率最低,引种前后降幅最大,说明其对引种地的适应性不及中间锦鸡儿。  相似文献