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In this study, we analyze the conservation status of Ethiopia's amphibian and reptile diversity in terms of coverage with protected areas and global representation in conservation breeding facilities. We identify conservation gaps and suggest priorities for improvement.
Kolja Sperling +3 more
wiley +1 more source
Occurrences of dust storms and long‐distance movement of dust across landscapes is constantly increasing in south Asia. This dust is expected to have profound impact on vegetation health and sustainability as dust may contribute to nutrient budgets of the forest ecosystems, while it could impart various stresses to the plants.
Shree P. Pandey +2 more
wiley +1 more source
在低钾土壤培养和营养液培养的条件下,采用植株含钾量、吸钾速率和钾素利用率并结合植株根系形态特征,对蕺菜属(Houttuynia Thunb.)16份不同基因型材料的富钾能力进行筛选。结果表明,峨眉蕺菜W01-86以及蕺菜W01-34和W01-71在低钾土壤培养和溶液培养时植株含钾量分别高于9.0%,5.50%,吸钾速率大于1.50μmol/(g.h),低钾土壤培养和溶液培养时的钾素利用率分别高于2.50,0.30g/g,为富钾基因型;W01-4和W01-99低钾土壤培养和溶液培养时的植株含钾量分别低于8.
邹宇婷 +4 more
doaj
为了探讨生物有机肥与减量配施化肥对连作黄瓜养分利用率和产量的影响,采用田间小区试验,以黄瓜为供试作物,共设9个处理(T1~T9),将9个处理分为3个处理组:生物有机肥添加量为0 t/hm2的CK处理组(T1减肥0%,T2减肥10%,T3减肥20%);生物有机肥添加量为10 t/hm2的Y1处理组(T4减肥0%,T5减肥10%,T6减肥20%);生物有机肥添加量为20 t/hm2的Y2处理组(T7减肥0%,T8减肥10%,T9减肥20%)。结果表明:Y1处理组和Y2处理组与CK处理组相比 ...
李小萌 +6 more
doaj
Multiple global change factors alter the scaling of nitrogen to phosphorus in alpine plants
Read the free Plain Language Summary for this article on the Journal blog. Abstract The stoichiometry and allometry of nitrogen (N) and phosphorus (P) reflect nutrient absorption and dynamic allocation by plants, and can be regulated by global change factors (e.g. nitrogen enrichment, climate warming and altered precipitation). Yet, how multiple global
Jiapu Li +10 more
wiley +1 more source
为明确增密减氮对烤烟产质量及肥料利用率的调控效应。以烤烟品种"云烟105"为材料,研究种植密度(13 890,15 150,16 665株/hm2)和施氮水平(0,84,94.5,105 kg/hm2)及其互作对烤烟产质量及养分利用效率的影响。结果表明:适度增密减氮能显著提高烤烟肥料利用率、产量和产值,使烟叶总糖、还原糖、钾含量显著升高,总氮、烟碱含量降低,对水溶性氯无显著影响,烟叶化学品质更加协调。烟叶化学成分协调性及烤烟氮磷钾利用率显著受年份、密度、施氮及年份×施氮、密度×施氮、年份×密度 ...
余小芬 +10 more
doaj
探究盐氮效应对棉花氮素动态积累、运转及利用效率的影响机制。以棉花“新陆中68号”为材料,设置土壤盐分含量为S1(2.5~3 g/kg)、S2(5~6 g/kg)和S3(8~9 g/kg),施氮量分别N1(105 kg/hm2)、N2(210 kg/hm2)、N3(315 kg/hm2)处理进行田间小区试验。通过Logistic生长函数模型对各器官生物量氮素累积进行拟合,以Vm(最高累积速率)和Δt(持续时间)为2个动态特征指标分析盐氮对棉花生物量氮素快速累积时间和速率的影响。结果表明,营养器官(根、茎 ...
余天源, 何新林, 衡通
doaj
P relim inary resu lts concern ing th e spa tio2tempora l pa ttern and mechan ism of n itrogen sources and expor ts in th e J iu long R iver wa tersh ed [PDF]
[摘要]:综合运用定位监测、野外试验、模型模拟与G IS技术等手段和方法, 定量研究了南亚热带地区九龙江流域和五川小流域氮的大气沉降、河 流输送(地表径流)、淋失、反硝化和氨挥发等输入输出(源汇)时空模式与机理. 结果表明, 九龙江流域氮/ 源0以化肥与饲料输入为主(占总输 入125. 6kg# hm- 2的86% ), 氮/ 汇0以氨挥发和河流输送为主(占总输出72. 9kg# hm- 2的82% ). 氮输入后50%以上进入大气和水环境, 14.
CHEN Nengwang +5 more
core
Abstract Black women are more likely to experience traumatic birthing events, more likely to experience perinatal depression, and less likely to receive mental health treatment than women of other racial and ethnic backgrounds, and yet largely overlooked in perinatal mental health research.
Helenia Quince +3 more
wiley +1 more source
研究旨在通过大田试验了解水分调亏对膜下滴灌板蓝根生长、耗水规律、产量、水分利用效率及品质的影响。于2018年在甘肃河西中部的民乐县益民灌溉试验站开展板蓝根水分控制试验,在板蓝根苗期和肉质根生长期保持充分灌水,营养生长期和肉质根生长期分别进行不同梯度(轻度、中度和重度)的水分调亏处理,并测定各项生长指标、产量、水分利用效率和品质。结果表明:(1)营养生长期和肉质根生长期中度和重度水分调亏显著降低了板蓝根株高、叶片数、主根长和主根直径,且降幅随调亏程度的加剧而增大,而轻度水分调亏与对照组无显著差异。(2 ...
王泽义 +5 more
doaj

