Factors effecting the plant uptake 影响养分吸收的因素主要包括介质中的养分浓度、温 度、光照强度、士壤水分、通气状况、土壤pH值、养分离 子的理化性质、根的代谢活性、苗龄、生育时期植物体内养 分状况等

The short distance transports of nutrients There are two main steps nutrients translocation in plant after nutrients absorbed by the root. One is the centripetal transport from the rhizoplane through the cortex tissue of the roots towards the xylem vessels of the central cylinder. Another one is the vertical transport from from the root towards the leaves

Calcium in physiology Uptake and translocation Higher plants often contain apprecia ble amounts Ca and generally in the order of about 5-30 mg Ca/g dry matter The high Ca2+ concentrations related with the high Ca2+ levels in media not related with the Ca2+ uptake

第一节复(混)合肥料的概念 第二节复(混)合肥料的成分、性质与施用 第三节复(混)肥料的合理施用

Plant K A. Potassium content of plants 1.20-50gkg-1 2. Plants take up large amount of K. Only N is taken up more. 3. In some plants (sugar beets and potatoes) K uptake is greater than N uptake

Concept of organic fertilizers Organic fertilizers-that are derived from the wastes and residues of plants or animals. Such as manure, sewage sludge etc. Some consist of unprocessed plant materials(such as tree leaves, grass clipping, crop residues, and green manure crops)

磷是作物必需的三要素之一 磷肥是世界上仅次于氮肥的主要肥料产品 磷在自然界中一般不以游离态(元素态)存在,而以磷酸盐形 式存在于矿物中。最常见的含磷矿物是磷灰石,通式为 Ca5X(PO4)3,其中X代表一F,-OH或-Cl等。最常见的氟磷灰 石的化学式为CaF(PO4)3。1989、1990年度,我国生产各种磷肥 453万吨(P2O5),居世界第二位

第一节能量来源及能量单位 一、能量来源 二、能量单位 第二节饲料能量在动物体内的转化 一、总能 二、消化能 三、代谢能 四、净能

一、碳水化合物及其营养生理作用 二、单胃动物碳水化合物营养 三、反刍动物碳水化合物营养

第一节 中国居民膳食营养参考摄入量 第二节 居民营养状况调查与社会营养监测 第三节 保证居民营养的膳食结构与政策措施