Results 11 to 20 of about 27,018 (162)
Shuitu Baochi Xuebao, 2022 为明晰重庆笋溪河流域河岸带水体、土壤和植物的氮磷特征及其影响因素,采用描述性统计、聚类分析、相关分析和冗余分析的方法,探讨三峡库尾小流域河岸带水体、土壤和植物的氮、磷含量特征、空间分布和各圈层氮磷的相关性及水体氮磷的影响因素。结果表明:(1)河岸带受河流区段影响,从上游到下游,水体氮磷与土壤全氮的含量先减小后增大,下游存在明显的农业氮输入,而土壤硝态氮、全磷和有效磷与植物氮磷的含量逐渐增加;(2)河岸带水体总氮与植物不同营养器官的氮含量均呈显著正相关 ...
孟海 +4 more
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Greenhouse gas emissions from croplands of China [PDF]
, 2003 China possesses cropland of 1.33 million km 2. Cultivation of the cropland not only altered the biogeochemical cycles of carbon (C) and nitrogen (N) in the agroecosystems but also affected global climate.
Bohan, Liao +13 more
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Functional Ecology, EarlyView.Read the free Plain Language Summary for this article on the Journal blog. Abstract Ecological communities are stressed by rapid and complex anthropogenic changes, threatening the persistence of biotic interactions and ecosystem functioning. Plant–pollinator communities, for instance, undergo structural transformations as a result of land‐use change ...
Erliang Gao +8 more
wiley +1 more source
Shuitu Baochi Xuebao, 2007 在大田条件下，以强筋小麦豫麦34为供试材料，在330kg／hm^2（高氮）、240kg／hm^2（中氮）2个供氮水平下施用纯硫0，20，60，100／hm^2，研究了不同供氮条件下施硫对小麦光合特性及产量的影响。结果表明：在适宜的供氮水平下施硫对小麦氮同化的关键酶硝酸还原酶（NR）活性、叶绿素SPAD值、叶片可溶性蛋白、旗叶光合速率均有促进的影响，高氮条件下有随施硫量的增加NR活性、叶片中可溶性蛋白含量以及旗叶光合速率有减少的趋势。在2个供氮水平下施硫均对干物质积累量和籽粒产量影响效果明显 ...
朱云集 +5 more
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Functional Ecology, EarlyView.Read the free Plain Language Summary for this article on the Journal blog. Abstract Grasslands worldwide are experiencing severe degradation due to overgrazing, climate change and anthropogenic disturbances, resulting in substantial declines in biodiversity and ecosystem functioning.
Xiaoqi Wang +5 more
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Ecology and Evolution, Volume 16, Issue 5, May 2026.This study reveals a shift in woody plant community assembly from competitive exclusion in early succession to habitat filtering in later stages within karst areas. Environmental distance (80.54%) contributed significantly more than geographical distance (9.95%), providing strong quantitative evidence that niche processes, particularly habitat ...
Hongfen Hu +5 more
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Rare Metals, Volume 45, Issue 5, May 2026.ABSTRACT Integrating light emission and electromagnetic wave (EMW) absorption into a single material opens up possibilities for multienvironmental applications. Herein, we propose a novel “molecular engineering‐pyrolysis conversion” strategy to construct a bifunctional system with tunable photoluminescence and efficient EMW absorption performance.
Renjie Wang +7 more
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Preparation and Characterization of BN Coating on SiC Fibers by Carbothermal Reduction [PDF]
, 2016 本论文以硼酸三甲酯（trimethylborate—TMB）蒸气为硼源、NH3气为氮源，采用碳热还原氮化法在SiC纤维表面制备BN涂层。首先，SiC纤维与Cl2气反应表面生成碳化物衍生碳（carbide-derivedcarbon—CDC）层，然后，CDC层与TMB蒸气及NH3气在1300C发生碳热还原氮化反应，生成BN涂层。采用FT-IR、XPS、XRD、AES、SEM、TEM、电阻率测试、单丝拉伸试验等系统地研究了所得BN涂层的组成、结构和性能。研究发现 ...
袁梦娇
core
Rare Metals, Volume 45, Issue 5, May 2026.ABSTRACT Composite materials hold significant potential for abrasive sealing, yet composite materials used for abrasive sealing fall short in service durability under extreme environments. Here, a controllable strategy for adjusting pore structure is proposed, aiming to design a YSZ(ESP)/BN@ZrO2‐polyester coating with hybrid micron/nanometer ...
Shuang Yu +8 more
wiley +1 more source
Shuitu Baochi Xuebao, 2019 为阐明不同土地利用类型土壤碳（C）、氮（N）、磷（P）生态化学计量学特征，对福州农田不同土地利用类型（水稻田、菜地和茉莉园）下的土壤全碳（TC）、全氮（TN）、全磷（TP）含量及其生态化学计量学特征进行测定和分析。结果表明：土壤TC含量均值基本表现为水稻田 > 菜地 > 茉莉园（P 菜地 > 茉莉园（P 水稻田 > 茉莉园 ...
刘旭阳 +5 more
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