Results 31 to 40 of about 6,221 (109)
目的为探究秸秆还田配合调控种植密度对玉米氮素利用效率与产量的影响。方法于2023年开展田间试验,设置秸秆离田(C,对照)和秸秆全量还田(X)同3种玉米种植密度67 500(D1,对照)、82 500(D2)、90 000株/hm²(D3)相结合,共设置6个处理。探究秸秆还田与种植密度对玉米氮素吸收利用和产量的影响。并将试验所得结果与参数修正后的DNDC(denitrification decomposition,DNDC)模型模拟结果进行比较分析,验证短期试验的可靠性。结果1)在相同种植密度下 ...
孙嘉璐 +6 more
doaj +2 more sources
通过野外实地调查和试验观测,对煤矿区矸石山人工植物群落的生长规律、土壤水文生态效应及其制约因素进行了研究.结果表明煤矸石山植物群落经过9年的自然演替和生长过程,其种类及数量发生了较大变化,已形成了由15个乔木树种、12个灌木树种和18种草本组成的人工植物群落.混交林群落中木本植物(乔、灌木)群体密度达到11 220株/hm2.9年生刺槐种群(密度3 333株/hm2,株行距1.5 m×2.0 m)的林木平均胸径为5.27 cm,平均高为5.15 m,平均冠幅为2.85 m ...
张光灿 刘霞 王燕
doaj
We collated detections of the sun bear from new and previously published camera trap studies across its range. We then analysed these detections at two different spatial scales to assess the habitat associations and diel activity of this species. We found that the sun bear is tolerant to moderate habitat disturbances. ABSTRACT Degraded tropical forests,
Alexander Hendry +5 more
wiley +1 more source
以黄土丘陵区4种典型植物种群(狼牙刺、白羊草、铁杆蒿、达乌里胡枝子)为研究对象,采用野外采样、室内模拟试验与分析相结合的方法,对0—30 cm土层的各径级根系密度参数(根长密度、根体积密度、根表面积密度)与土壤理化性质、土壤分离速率间的关系进行了研究。结果表明:(1)4种植物的根系径级主要集中在0<D≤1.0 mm之间,86%~93%的根长和46%~61%的根系表面积分布在此范围内,且根系径级越大,根系各密度参数越小;(2)4种植物各径级根密度参数对土壤理化性质(容重、有机质、团聚体)的影响各不相同 ...
葛芳红 +5 more
doaj
ABSTRACT Platinum (Pt)‐based catalysts are crucial for the commercialization of hydrogen/metal air batteries, but they suffer from Pt scarcity, high cost, and nanoparticle dissolution/agglomeration, mainly leading to performance degradation. We address this by synthesizing a PtFe alloy catalyst (PtFe–PA–NC) via a phytic acid (PA) assisted pyrolysis ...
Chenyang Shu +9 more
wiley +1 more source
探讨株行距配置调整后密度对旱地覆膜春玉米连作稳产和水分利用的影响,为旱地雨养区春玉米高产稳产栽培提供依据。试验于2014-2017年在黄土旱塬区甘肃省镇原县(35°30'N,107°39'E)进行,以紧凑型耐密高产春玉米品种"先玉335"为试验材料,设55,75 cm 2种等行距垄沟覆盖种植方式,6.0,7.5,9.0,10.5万株/hm2 4个种植密度水平,采用裂区设计,连作定位观测。使用烘干法测定不同处理春玉米生育期0-200 cm土层土壤水分,研究黄土旱塬连作春玉米籽粒产量和土壤剖面水分变化 ...
王磊 +8 more
doaj
Read the free Plain Language Summary for this article on the Journal blog. Abstract Forests worldwide are increasingly impacted by drought due to climate change, prompting plants to adapt through dehydration tolerance (DT) and avoidance (DA), two distinct physiological strategies.
Xingyun Liang +11 more
wiley +1 more source
口腔种植技术是在牙槽突内植入一人工装置并与颌骨结合,用以支撑和固位修复体,完成对缺牙的修复[1],其具有一定的复杂性。因此,如何确保口腔种植体修复成功是至关重要的。学者们主要从种植体植入后的动度、骨吸收量、骨密度的变化等方面对种植体成功与否进行评定[2]。1986年Albrektsson等学者确立种植体成功标准为:单个种植体无松动;X线检查种植体周围无明显的阴影透射区 ...
刘润喆, 王蕊
doaj
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
Mycorrhiza‐induced alterations in the spatial structure of stands in a subtropical forest
Read the free Plain Language Summary for this article on the Journal blog. Abstract Spatial aggregation patterns represent snapshots of ecological processes that occurred over an extensive period. Such processes can shape both the conspecific and the heterospecific spatial structure of plants across woody habitats.
Jingjing Xi +6 more
wiley +1 more source

