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Journal of Forestry Research 2020年第6期31卷 2435-2444页

作者： Yunyun Wang Jalene M.La.Montagne Fei Lin Zuoqiang Yuan Ji ye Xugao Wang Zhanqing hao CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016People’s Republic of China Department of Biological Sciences DePaul UniversityChicagoIL 60614USA

Seed distribution and deposition patterns around parent trees are strongly aff ected by functional traits and therefore infl uence the development of plant *** assess the limitations of seed dispersal and the extent to which diaspore and neighbouring parental traits explain seed rain,we used a 9-year seed data set based on 150 seed traps in a 25-ha area of a temperate forest in the Changbai *** 480,598 seeds belonging to 12 families,17 genera,and 26 species were identifi ed,only 54%of the species with mature trees in the community were represented in seeds collected over the 9 years,indicating a limitation in seed *** species were most limited;overstory species were least *** with wind-dispersed seed had the least limitation,while the lowest similarity in species richness was for animal-dispersed species followed by gravity-dispersed species;fl eshy-fruited species had stronger dispersal limitations than dry-fruited *** linear mixed models showed that relative basal area had a signifi cant positive eff ect on seed abundance in traps,while the contribution of diaspore traits was low for nearly all *** results suggest that tree traits had the strongest contribution to seed dispersal and deposition for all functional groups examined *** fi ndings strengthen the knowledge that tree traits are key in explaining seed deposition patterns,at least at the primary dispersal *** improved knowledge of sources of seeds that are dispersed could facilitate greater understanding of seedling and community dynamics in temperate forests.

关键词： Seed rain Dispersal mechanisms Tree traits Basal area Changbai mountain Temperate forest

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Crystal Structure,Nano-particle Morphology and Interaction with ATP of [NH_3CH_2CH(NH_2)CH_3]_2 [M(Ⅵ)O_2(OC_6H_4O)_2](M= Mo_(0.6)W_(0.4))and Its Activity to Promote DNA Cleavage

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Chemical Research in Chinese Universities 2007年第6期23卷 635-640页

作者： LU Xiao-ming PANG Xiao-li LI Zhi-qiang WANG Ting WANG Zhen ye Chao-hui Department of Chemistry Capital Normal University Beo＇ing 100037 P. R. China Wuhan Institute of Physics and Mathematics Chinese Academy of Science Wuhan 430071 P. R. China

The title complex [ NH3 CH2 CH （ NH2 ） CH3 ]2 [ M （ Ⅵ ） O2 （ OC6 H4 O）2 ] （ M = Mo0. 6 W0.4 ） was synthesized via a simple solution-phase ehemieal route. The determination of single erystal X-ray diffraction revealed that the title eompound is erystallized in a monoelinie system with P2（ 1 ）/n spaee group, a = 1. 0913（10） nm, b = 1. 0442（10） nm, c=1.8842（19） nm, α=90°, β=96.530（17）°, γ=90°, Z=4, and V=2.133（4） nm^3. The mononuelear anionie unit [ M （ Ⅵ ） O2 （ 0C6 H4 O） 2 ] 2 - displays ehiral pseudo-oetahedral [ MO6 ] eoordination geometry and is linked by ehiral eations via hydrogen bond and π…π stacking interaetion. The transmission electron microseopy images show that the title eomplex is eomprised of nano-partieles with diameters ranging from 20 to 50 nm. The NMR study shows the ^1H downfield chemical shifts of [ NH3 Cha Hb CH （ NH2 ） CH3 ]^＋ eations in the title eomplex when it is mixed with adenosine-triphosphate（ ATP）, and the chemical shift difference between ha and Hb is inereased greatly, and most of the eateeholate ligands dissociate from the eentral metal atoms. The DNA cleavage aetivity experiment reveals that DNA eleavage promoted by the title eomplex is lower than that by Na2 MoO4 whieh possesses antitumor propetty, but higher than that by Na2WO4.

关键词： Crystal structure Nano-partiele NMR ATP DNA cleavage activity

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运动对苏尼特羊肌纤维组织学特性和肉品质的影响及其调控机理

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动物营养学报 2022年第2期34卷 1140-1150页

作者：孙冰侯艳茹白艳苹侯普馨苏琳靳烨哈斯高娃内蒙古农业大学食品科学与工程学院呼和浩特010018 乌拉特中旗农牧和科技局乌拉特中旗015300

本试验以6月龄苏尼特羊为研究对象,采用肌球蛋白重链(MyHC)分子分型法、ATP酶染色法分析肌纤维组织学特性,并对肉品质指标、能量代谢相关基因mRNA相对表达量、代谢酶活性进行测定及分析,以探究运动对苏尼特羊肌纤维特性和肉品质的影响... 详细信息

本试验以6月龄苏尼特羊为研究对象,采用肌球蛋白重链(MyHC)分子分型法、ATP酶染色法分析肌纤维组织学特性,并对肉品质指标、能量代谢相关基因mRNA相对表达量、代谢酶活性进行测定及分析,以探究运动对苏尼特羊肌纤维特性和肉品质的影响及其调控机理。选取体况良好、平均体重为(19.77±3.81)kg的3月龄苏尼特羊14只,随机分为2组:运动组和对照组,每组7只。对照组和运动组在相同的圈中集中饲养,运动组每日在运动场内进行6 km的驱赶运动。预试期7 d,正试期90 d。结果表明:1)运动组苏尼特羊Ⅰ型肌纤维横截面积、直径,Ⅱa型肌纤维数量比例、直径、横截面积、面积比例显著或极显著高于对照组(P<0.05或P<0.01),肌纤维密度、Ⅱb型肌纤维面积比例和数量比例显著或极显著低于对照组(P<0.05或P<0.01)。2)运动组苏尼特羊肌肉中琥珀酸脱氢酶(SDH)、乳酸脱氢酶(LDH)活性以及MyHCⅡa、MyHCⅡx、一磷酸腺苷激活的蛋白激酶α1(AMPKα1)、过氧化物酶体增殖激活受体γ辅助激活信号因子-1α(PGC⁃1α)、细胞色素C氧化酶Ⅳ(COXⅣ)mRNA相对表达量显著或极显著高于对照组(P<0.05或P<0.01)。3)运动组苏尼特羊肌肉初始pH以及红度(a^(∗))、黄度(b^(∗))、亮度(L^(∗))值和饱和度显著或极显著低于对照组(P<0.05或P<0.01),剪切力、pH_(24 h)显著或极显著高于对照组(P<0.05或P<0.01)。综上所述,运动增强苏尼特羊肌肉的氧化代谢能力,促进氧化型肌纤维生成,并能有效延缓宰后pH的下降,但不利于肌肉的色泽和嫩度。

关键词：运动苏尼特羊肌纤维特性代谢酶活性肉品质

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负荷跟踪机械补偿运行策略研究

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核科学与工程 2016年第4期36卷 459-464页

作者：叶青杨波汤春桃党哈雷上海核工程研究设计院上海200233

经济、灵活及与电网匹配的运行控制是先进核电厂的设计目标之一。本文对核电厂典型的控制模式和机械补偿运行控制策略进行了介绍,进一步以机械补偿设计理念为基础,研究分析了其在各种负荷跟踪模式下的运行特性。分析结果表明,采用机械... 详细信息

经济、灵活及与电网匹配的运行控制是先进核电厂的设计目标之一。本文对核电厂典型的控制模式和机械补偿运行控制策略进行了介绍,进一步以机械补偿设计理念为基础,研究分析了其在各种负荷跟踪模式下的运行特性。分析结果表明,采用机械补偿运行策略可实现多种模式下的负荷跟踪运行,并且在绝大部分寿期内可实现URD要求的50%额定功率以上不调硼日间负荷跟踪运行。且在满足功率负荷变化及能量输出需求的前提下,功率峰因子还具有足够的裕量。由此说明机械补偿运行策略可以较大幅度地提升电厂的运行灵活性、经济性以及与电网匹配的适应性。

关键词：机械补偿负荷跟踪负荷调节

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高校与区县经济增长——基于主要城市新建校区的实证分析

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北京大学教育评论 2021年第3期19卷 125-153,191,192页

作者：陈东阳哈巍叶晓阳北京大学教育经济研究所北京100871 布朗大学安纳伯格学校改革研究所罗得岛

高校扩招后,部分本科院校由于办学资源紧张选择到城市郊区新建校区。本文以此为研究契机,在区县一级的微观层次重新讨论高等教育与地区经济增长这一经典议题。本文使用国内主要城市的148个区县19年的面板数据,基于多期DID模型、事件研... 详细信息

高校扩招后,部分本科院校由于办学资源紧张选择到城市郊区新建校区。本文以此为研究契机,在区县一级的微观层次重新讨论高等教育与地区经济增长这一经典议题。本文使用国内主要城市的148个区县19年的面板数据,基于多期DID模型、事件研究和合成控制法进行分析,发现新建校区对所在区县整体经济增长具有促进作用,并且对第二产业和第三产业的经济活动影响最为明显。高校融入所在地的经济增长存在时间滞后性,但随着时间的延长,高校对经济增长的影响不断扩大。新建校区的影响效果存在一定异质性,中西部地区新建校区的促进作用更大,而已有老校区的存在有可能削弱新建校区的影响。

关键词：新建校区经济增长区县高校

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habitat associations of saplings and adults in an old-growth temperate forest in the Changbai mountains, northeastern China

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Forestry Studies in China 2011年第1期13卷 13-22页

作者： ye Ji haO Zhan-qing XIE Peng LI jing-gong Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 E R. China Graduate University of Chinese Academy of Sciences Beijing 100049 R R. China Jilin Provincial Academy of Forestry Sciences Changchun 130033 R R. China The Changbai Mountain Natural Reserve Administration Changbaishan 113613 R R. China

Species-habitat association analysis is useful to detect spatial arrangement of individual plants, to discover rules about the distribution of species and to generate hypotheses about the possible underlying process controlling observed structures. Quantifying methods were used to classify habitats in terms of topographical variables in a mixed temperate broad-leaved Korean pine forest of the Changbai mountains in northeastern China. All of the 625 20 m × 20 m quadrats of the plot could be unambiguously assigned to one of three habitat categories （low-plateau, high-plateau and slope）. Torus-translation tests were used to estimate species-habitat associations. Many species are clearly distributed in a biased fashion with respect to habitats. Fifteen （55.6%） out of 27 species showed strong positive or negative association with specific habitats. We compared species-habitat associations at the sapling and adult stages. Adjusted density values indicated few species exhibit extremely strong habitat associations. Only 9 out of 26 species had adjusted densities 〉 3 in the habitat for which they had strong positive affinity. Few species show the same associations at the small tree and large tree stages. Only 3 out of 22 occurring associations with a specific habitat appeared to have a consistent habitat association at the two stages. These results suggest that species-habitat associations exist in the 25-ha plot of the temperate forest of the Chang- bai mountains. Owing to limitations in our statistical methodology, we partly underestimated associations by ignoring rare species. Regeneration niches can contribute to co-existence, but regeneration niches due to habitat associations play a limited role in species co-existence, since most species show a similar trend in habitat associations at the sapling and adult stages. We should pay more attention to shifts in habitat associations, i.e. niche shifts at different stages of existence.

关键词： niche differentiation habitat association environmental heterogeneity saplings and adults life stages

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Standards of Ecological Compensation for Traditional Ecoagriculture:Taking Rice-Fish System in hani Terrace as an Example

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Journal of Mountain Science 2014年第4期11卷 1049-1059页

作者： LIU Mou-cheng XIONG Yin YUAN Zheng MIN Qing-wen SUN ye-hong Anthony M.Fuller Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences School of Environment and Natural Resources Renmin University of China Institute of Tourism Beijing Union University

Traditional eco-agriculture provides many ecosystem services which are important for the local environment, especially in mountain areas. In order to encourage the farmers to engage in coo-agriculture, it is necessary to establish an eco-compensation mechanism for them. As the compensation standard is one of key issues in establishing eeo-compensation mechanism, this paper calculated the standard based on the farmers＇ willingness to accept （WTA） and the input-output analysis of eco-compensation. We took the traditional rice-fish eco-agriculture as the research object, conducting field surveys in hani Terrace of Honghe County. Through the questionnaires in 2o11, we obtained the farmers＇ willingness to accept government compensation and market compensation. Then, the research evaluated the output of eco-compensation, the economic value of rice-fish paddy ecosystem services. Finally, under different market compensation standards, we compared the input and output of government compensation. The results show that, in 2011 the government should to pay farmers 7462 ***^-1·a^-1 to meet their willingness, but the output （ecological benefit） was only 7393 ***^-1·a^-1. However, whenthe rice price increases 1 yuan·kg-1 because of the limited use of chemicals in the next year, the government just has to pay farmers 4062 ***^-1·a^-1 and the surplus will be 3331 ***^-1·a^-1.

关键词： Eco-compensation Eco-agriculture Ecosystem services Cultivation system hani Terrace.

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Irrigation water salinity and N fertilization:Effects on ammonia oxidizer abundance, enzyme activity and cotton growth in a drip irrigated cotton field

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Journal of Integrative Agriculture 2016年第5期15卷 1121-1131页

作者： MIN Wei GUO Hui-juan ZhaNG Wen ZHOU Guang-wei MA Li-juan ye Jun HOU Zhen-an Department of Resources and Environmental Science Shihezi University

Use of saline water in irrigated agriculture has become an important means for alleviating water scarcity in arid and semi-arid regions. The objective of this field experiment was to evaluate the effects of irrigation water salinity and N fertilization on soil physicochemical and biological properties related to nitrification and denitrification. A 3×2 factorial design was used with three levels of irrigation water salinity（0.35, 4.61 and 8.04 d S m-1） and two N rates（0 and 360 kg N ha^（-1））. The results indicated that irrigation water salinity and N fertilization had significant effects on many soil physicochemical properties including water content, salinity, p H, NH_4-N concentration, and NO_3-N concentration. The abundance（i.e., gene copy number） of ammonia-oxidizing archaea（AOA） was greater than that of ammonia-oxidizing bacteria（AOB） in all treatments. Irrigation water salinity had no significant effect on the abundance of AOA or AOB in unfertilized plots. However, saline irrigation water（i.e., the 4.61 and 8.04 d S m-1 treatments） reduced AOA abundance, AOB abundance and potential nitrification rate in N fertilized plots. Regardless of N application rate, saline irrigation water increased urease activity but reduced the activities of both nitrate reductase and nitrite reductase. Irrigation with saline irrigation water significantly reduced cotton biomass, N uptake and yield. Nitrogen application exacerbated the negative effect of saline water. These results suggest that brackish water and saline water irrigation could significantly reduce both the abundance of ammonia oxidizers and potential nitrification rates. The AOA may play a more important role than AOB in nitrification in desert soil.

关键词： saline water nitrogen fertilizer ammonia-oxidizing microorganisms enzyme activity cotton yield

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Post-silking nitrogen accumulation and remobilization are associated with green leaf persistence and plant density in maize

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Journal of Integrative Agriculture 2019年第8期18卷 1882-1892页

作者： ZhaNG Li-li ZHOU Xiang-li FAN ye FU Jun HOU Peng YANG hai-long QI Hua Agronomy College Shenyang Agricultural University Shenyang 110866 P.R.China Dandong Academy of Agricultural Sciences Fengcheng 118109 P.R.China College of Life Sciences Northwest A&F University Yangling 712100 P.R.China Institute of Crop Sciences Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China

Stay green(SG) maize was found to have higher grain yield and post-silking nitrogen(N) uptake(PostN) compared with a non-stay green(NSG) hybrid. To understand the effects of plant density on grain yield(GY) and N efficiency in modern maize hybrids, we compared two modern hybrids(SG hybrid DY508 and NSG hybrid NH101) with similar maturity ratings at three plant densities(45 000, 60 000, and 75 000 pl ha^–1) in 2014 and 2015. GY, leaf senescence, dry matter(DM) accumulation,N accumulation, PostN, and post-silking N remobilization(RemN) were analyzed. DY508 and NH101 had similar GY, but DY508 had higher thousand kernel weight(TKW) and lower kernel number(KN) than NH101. Plant density significantly increased GY in the two hybrids. On average, over the two years, plant density improved GY in DY508 and NH101 by 18.5 and 11.1%, respectively, but there were no differences in total dry matter(TDM) and post-silking DM(PostDM) between the two hybrids. Plant density improved leaf N, stem N, and grain N at the silking and maturity stages in 2014 and 2015. DY508 was lower in harvest index(HI), nitrogen harvest index(NHI), and grain N concentration(GNC) than NH101. Grain N in DY508 was 2.61 kg ha^–1 less than in NH101, and this was caused by lower GNC and leaf RemN. On the average, DY508 was 1.62 kg ha^–1 less in leaf remobilized N(leaf RemN) than NH101, but was similar in stem remobilized N(stem RemN;2.47 kg ha^–1 vs. 3.41 kg ha^–1). Maize hybrid DY508 shows delayed leaf senescence in the upper and bottom canopy layers in the later stages of growth. The present study provides evidence that the NH101, which has rapid leaf senescence at the late grain-filling stage, has gained equivalent GY and higher leaf RemN, and was more efficient in N utilization.

关键词： maize N remobilization post-silking N uptake stay green plant density

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Rice productivity and profitability with slow-release urea containing organic-inorganic matrix materials

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Pedosphere 2021年第4期31卷 511-520页

作者： Yang YANG Binmei LIU Xiaoyu NI Liangzhi TAO Lixiang YU ye YANG Mengxi FENG Wenjin ZHONG Yuejin WU Engineering Laboratory of Environment-friendly High-effciency Fertilizers and Pesticides of Anhui Province Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031(China) The Innovative Academy of Seed Design Chinese Academy of SciencesBeijing 100101(China) Henan Xinlianxin Fertilizer Co. Ltd.Xinxiang 453700(China)

Applying slow-release fertilizers is possible means for reducing nitrogen(N) loss in rice production. Matrix-based fertilizers represent novel slow-release fertilizers. To date, there is little consensus about the effect of combined addition of organic and inorganic matrix materials on rice production. We developed a slow-release urea fertilizer with selected organic and inorganic matrix materials. The study aimed to: i) determine the effect of the slow-release urea on rice yield, profit, and agronomic efficiency and ii) elucidate its possible mechanisms. A two-year field experiment was conducted during 2015–2016. Besides,laboratory experiments were conducted to determine the potential N loss risk. Three treatments were set up: control without N application(CK), regular urea treatment(RU, 150 kg N ha^(-1)), and slow-release urea treatment(SU, 150 kg N ha^(-1)). The results showed that rice biomass and grain yield were significantly higher in SU than in RU(P ha^(-1), higher than in RU. Agronomic efficiency was significantly greater in SU than in RU(P han in RU. Less N loss and greater soil N availability were partly responsible for the improvements in rice growth traits and physiological parameters in SU. Overall, the slow-release urea is a promising fertilizer for rice production.

关键词： ammonia emission ferric sulfate matrix-based fertilizer montmorillonite nitrogen leaching path analysis

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