The research analyzed characters of rice/wheat growth and yield structure in Puyang and explored the effects of droughts and floods on the crops. The re-sults showed that droughts and floods had significant effects on...The research analyzed characters of rice/wheat growth and yield structure in Puyang and explored the effects of droughts and floods on the crops. The re-sults showed that droughts and floods had significant effects on crop growth and yield. In Puyang, the relieving and prevention technology of the disasters is con-cluded. Specifical y, it is recommended to make ful use of agricultural climate re-sources in a rational way and select suitable crop varieties according to climate and disaster characters, fol owed by timely sowing and scientific crop arrangement. What＇s more, ploughing should proceed in deeper soil layers and management measures should be optimized to reduce the effects of disasters on crops. In addi-tion to that, disaster index system should be reinforced in terms of establishment, monitoring, warning and prevention to lay scientific foundations and provide refer-ences for safe crop production and preventing and reducing disasters.展开更多
为探究氮添加对濒危植物东北红豆杉幼苗生长-防御权衡的影响,为该物种的保护工作提供理论依据,本研究以东北红豆杉4年生幼苗为对象,进行了3种氮源(硫酸铵、硝酸铵和硝酸钾)和4个施氮量(30、60、90、120 kg N·hm^(-2)·a^(-1))...为探究氮添加对濒危植物东北红豆杉幼苗生长-防御权衡的影响,为该物种的保护工作提供理论依据,本研究以东北红豆杉4年生幼苗为对象,进行了3种氮源(硫酸铵、硝酸铵和硝酸钾)和4个施氮量(30、60、90、120 kg N·hm^(-2)·a^(-1))的氮添加实验。结果表明:(1)东北红豆杉幼苗的苗高增长量、地径增长量和总生物量随施氮量增加显著增加,施氮量超过90 kg N·hm^(-2)·a^(-1)后地径增长量和总生物量开始下降,施氮处理的幼苗根冠比显著低于对照组,但在不同施氮量下无显著差异;(2)净光合速率(Pn)和气孔导度在氮添加处理后显著提高,在施氮量为90 kg N·hm^(-2)·a^(-1)时达峰值,胞间CO_(2)浓度与Pn的变化方向相反,说明氮添加可以缓解植物的非气孔限制;(3)黄酮类化合物含量在施氮后呈现先增高后降低的趋势,施氮量30 kg N·hm^(-2)·a^(-1)为转折点;(4)施氮后,生长指标与光合指标呈显著正相关,类黄酮指数与光合指标呈显著负相关,净同化率、相对生长速率和黄酮类化合物指数变化符合生长-分化平衡假说;(5)硝酸铵处理相对单一态氮处理对幼苗的地上部分生长、气孔导度和花青素合成具有促进作用,硝酸钾处理下类黄酮指数显著提高。总的来说,东北红豆杉幼苗对氮添加的响应与施氮量和氮素类型有关,当氮添加为30~90 kg N·hm^(-2)·a^(-1)时,东北红豆杉幼苗的生长发育和防御水平较优,可作为东北红豆杉迁地保护或野外回归的参考措施。展开更多
文摘The research analyzed characters of rice/wheat growth and yield structure in Puyang and explored the effects of droughts and floods on the crops. The re-sults showed that droughts and floods had significant effects on crop growth and yield. In Puyang, the relieving and prevention technology of the disasters is con-cluded. Specifical y, it is recommended to make ful use of agricultural climate re-sources in a rational way and select suitable crop varieties according to climate and disaster characters, fol owed by timely sowing and scientific crop arrangement. What＇s more, ploughing should proceed in deeper soil layers and management measures should be optimized to reduce the effects of disasters on crops. In addi-tion to that, disaster index system should be reinforced in terms of establishment, monitoring, warning and prevention to lay scientific foundations and provide refer-ences for safe crop production and preventing and reducing disasters.
文摘为探究氮添加对濒危植物东北红豆杉幼苗生长-防御权衡的影响,为该物种的保护工作提供理论依据,本研究以东北红豆杉4年生幼苗为对象,进行了3种氮源(硫酸铵、硝酸铵和硝酸钾)和4个施氮量(30、60、90、120 kg N·hm^(-2)·a^(-1))的氮添加实验。结果表明:(1)东北红豆杉幼苗的苗高增长量、地径增长量和总生物量随施氮量增加显著增加,施氮量超过90 kg N·hm^(-2)·a^(-1)后地径增长量和总生物量开始下降,施氮处理的幼苗根冠比显著低于对照组,但在不同施氮量下无显著差异;(2)净光合速率(Pn)和气孔导度在氮添加处理后显著提高,在施氮量为90 kg N·hm^(-2)·a^(-1)时达峰值,胞间CO_(2)浓度与Pn的变化方向相反,说明氮添加可以缓解植物的非气孔限制;(3)黄酮类化合物含量在施氮后呈现先增高后降低的趋势,施氮量30 kg N·hm^(-2)·a^(-1)为转折点;(4)施氮后,生长指标与光合指标呈显著正相关,类黄酮指数与光合指标呈显著负相关,净同化率、相对生长速率和黄酮类化合物指数变化符合生长-分化平衡假说;(5)硝酸铵处理相对单一态氮处理对幼苗的地上部分生长、气孔导度和花青素合成具有促进作用,硝酸钾处理下类黄酮指数显著提高。总的来说,东北红豆杉幼苗对氮添加的响应与施氮量和氮素类型有关,当氮添加为30~90 kg N·hm^(-2)·a^(-1)时,东北红豆杉幼苗的生长发育和防御水平较优,可作为东北红豆杉迁地保护或野外回归的参考措施。
