Results 1 to 10 of about 1,129,124 (156)
Shuitu Baochi Xuebao, 2022 为研究传统耕作模式下坡耕地作物覆盖度对土壤侵蚀的影响,利用冬小麦不同的种植密度和生长期来模拟作物不同的覆盖度情况。采用人工模拟降雨方法测定0,150万,250万,350万,450万株/hm2 5种不同密度处理在不同生育期的覆盖度、地表径流和土壤侵蚀,分析作物覆盖度对土壤侵蚀的影响。结果表明:(1)坡耕地作物种植密度的不同导致覆盖度产生差异,对土壤侵蚀有明显的影响,作物覆盖度一般随种植密度的增加而增加,但如果密度过大,由于生长状况不佳,覆盖度反而变小,表现为7.5万株/hm2时覆盖度最大 ...
彭琼, 刘宝元, 曹琦, 刘逸滨
doaj
Shuitu Baochi Xuebao, 2022 植被恢复过程可显著影响土壤入渗性能。通过选取黄土高原典型草地白羊草和铁杆蒿草地，设置不同种植密度（5，10，15，20，25，30株/m2）和采用人工模拟降雨试验（60 mm/h，60 min），系统研究了草地植被特征对土壤入渗过程的影响。结果表明：（1）种植密度增加可显著延缓产流，不同种植密度下白羊草草地和铁杆蒿草地初始产流时间分别为0.76~5.74，0.87~2.08 s，且随盖度、根系生物量和有机质的增加呈幂函数增加（R2≥0.18 ...
蒋忙舟
doaj
, 2021 氮供给和种植密度是影响植物生长的两个重要因素。豆科植物因其生物固氮能力而在受到氮限制的生态系统中具有重要作用,氮含量增加促进植物生长的同时也会抑制豆科植物的生物固氮能力,种植密度会通过种内竞争影响豆科植物的生长和生物固氮能力,然而少有研究关注氮肥添加和种植密度对豆科植物生长和生物固氮能力的影响。该研究以达乌里胡枝子(Lespedeza davurica)为研究对象,通过温室盆栽实验,探究氮肥和种植密度对其生长和生物固氮的影响。实验设置4个氮添加水平(0、5、10、20 g·m~(–2)·a~(–1 ...
李磊 +6 more
core
Grain Boundary Density Governs the Discharge Behavior of Mg Anodes in Biodegradable Batteries
Rare Metals, Volume 45, Issue 11, November 2026.ABSTRACT Biodegradable magnesium (Mg) alloys have entered clinical use, yet their development as self‐powered absorbable batteries is hindered by poor anode performance, including high self‐corrosion, passivation, and nonuniform dissolution. The role of grain boundary density in governing discharge behavior remains unclear.
Xiaohui Shao +3 more
wiley +1 more source
Rare Metals, Volume 45, Issue 10, October 2026.ABSTRACT The use of Ti6Al4V alloy in dental implantation is constrained by its high elastic modulus and biological inertness, which lead to delayed osseointegration and a high failure risk. Additionally, its chemical incompatibility with hydroxyapatite (HA) impedes the development of stable bioactive composites.
Shangyong Zuo +8 more
wiley +1 more source
Rare Metals, Volume 45, Issue 10, October 2026.ABSTRACT Zinc‐based biodegradable metals are promising implant materials, and additive manufacturing offers a powerful route for their patient‐specific fabrication. However, process‐induced surface defects can accelerate degradation and compromise biocompatibility, rendering post‐processing essential.
Yixuan Shi +13 more
wiley +1 more source
牛山湖两种不同生境小型鱼类的种类组成、多样性和密度 [PDF]
, 2007 研究了2003年春季浅水草型湖泊牛山湖小型鱼类空间分布(种类组成、多样性和密度等)与生境异质性之间的关系.根据水生植被状况、离岸距离和水深,选择了两种差异较大且有代表性的生境类型,即近岸沉水植物茂密的生境A和远岸沉水植物稀疏的生境B.使用围网(180m2)在这两种生境中进行小型鱼类的采样,采用多次标志回捕法和Zippin去除法估算了围网内小型鱼类的密度.结果表明,两种不同生境中小型鱼类的种类组成、多样性度量值和密度估算值均存在一定程度的差异:1)生境A中的渔获物由5科14种小型鱼类组成 ...
李钟杰, 叶少文, 曹文宣
core
Rare Metals, Volume 45, Issue 10, October 2026.ABSTRACT Biomass‐based hydrogels are widely regarded as ideal substrates for self‐powered wearable sensors. However, the practical applications of hydrogels are commonly limited by their inherent low strength and toughness, which restrict their capacity to withstand repeated stretching, bending and other mechanical loads arising from human motion in ...
Boyu Du +9 more
wiley +1 more source
Uncovering correlates of decline and critical refuges for a threatened terrestrial mammal
Conservation Biology, Volume 40, Issue 4, August 2026.Abstract Globally, the geographic ranges of numerous species are contracting. Identifying spatiotemporal patterns of threat impact can illuminate why species decline in some parts of their range but persist in others. We developed a correlative approach to identify species’ response thresholds and locate ecological refuge areas associated with ...
Natalya M. Maitz +5 more
wiley +1 more source
, 2020 种植密度作为影响作物产量和品质的重要因素,会造成植物对于光照、水分和养分的竞争。为研究种植密度对苜蓿生长与产量的影响,在日光温室环境下,以紫花苜蓿(Medicago sativa)为材料,设置25、100、400、800、1 500、2 000株·m~(–2),共6个种植密度,对紫花苜蓿的种群密度和生长状况进行了观测。结果表明,各处理播种后15天的平均种植密度分别为25、100、373、745、1 255、1 938株·m~(–2);随着紫花苜蓿的生长,除了低密度(25、100株·m~(–2 ...
朱言坤 +8 more
core