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酸枣新品种“长丰”的选育
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作者 张海旺 陈光辉 +3 位作者 刘丽娜 申逸男 李思琪 张文臣 《北方园艺》 CAS 北大核心 2024年第3期157-160,F0002,共5页
“长丰”酸枣是从辽宁省朝阳地区众多野生酸枣中经过结实丰产性、特异性、稳定性、一致性及抗逆性等综合评价选育而成。果实圆柱形,熟时浅红色,硬质者深红色至暗红色,平均纵径20.40 cm,平均横径16.21 cm,果味甜酸,平均单果质量2.87 g,... “长丰”酸枣是从辽宁省朝阳地区众多野生酸枣中经过结实丰产性、特异性、稳定性、一致性及抗逆性等综合评价选育而成。果实圆柱形,熟时浅红色,硬质者深红色至暗红色,平均纵径20.40 cm,平均横径16.21 cm,果味甜酸,平均单果质量2.87 g,可食率92.00%,可溶性固形物含量32.00%,总酸含量3.48%,总糖含量28.32%。平均单核质量0.23 g、平均纵径10.38 mm、平均横径6.84 mm,平均单仁质量0.047 g。出仁率20.91%,双仁率28.00%,药食兼用。“长丰”酸枣平均果实产量为普通酸枣的2倍。 展开更多
关键词 酸枣 品种 “长丰” 选育
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抗TY粉果番茄新品种“长丰5号”的选育
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作者 李继纲 梁燕 +2 位作者 孙亚东 刘婧仪 秦蕾 《北方园艺》 CAS 北大核心 2017年第11期166-167,共2页
"长丰5号"是以R021自交系为母本,R017自交系为父本,配制而成的抗TY一代杂种。无限生长粉果类型,生长势强,667m^2平均产量7 627.2kg。果实高圆型,成熟果粉红色,无绿色果肩,外形美观,果实硬度好,耐贮运,货架寿命长,平均单果质量... "长丰5号"是以R021自交系为母本,R017自交系为父本,配制而成的抗TY一代杂种。无限生长粉果类型,生长势强,667m^2平均产量7 627.2kg。果实高圆型,成熟果粉红色,无绿色果肩,外形美观,果实硬度好,耐贮运,货架寿命长,平均单果质量250g左右。抗番茄黄化曲叶病毒病(TY)、番茄花叶病毒病(ToMV)、叶霉病、枯萎病。适合全国各地栽培。 展开更多
关键词 番茄 “长5号” 一代杂种 抗TY
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Altitudinal Range of Black-and-white Snub-nosed Monkeys (Rhinopithecus bieti ) at Baima Snow Mountain, China 被引量:5
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作者 钟泰 肖林 +3 位作者 霍晟 向左甫 肖文 崔亮伟 《Zoological Research》 CAS CSCD 北大核心 2008年第2期181-188,共8页
Faeces were counted along horizontal, 5.0m wide strips at altitude intervals of 100m to examine the altitudinal ranging pattern of a band of black-and-white snub-nosed monkeys (Rhinopithecus bieti) at Nanren (99... Faeces were counted along horizontal, 5.0m wide strips at altitude intervals of 100m to examine the altitudinal ranging pattern of a band of black-and-white snub-nosed monkeys (Rhinopithecus bieti) at Nanren (99°04′E, 28°34′N, Baima Snow Mountain Nature Reverse, Yunnan, China) at four areas in each season between 2000-2001. Faeces were also counted along vertical, 2.5 m wide strips in one subvalley and on one subridge in each area. Monkeys used an altitudinal range of 3500-4300m, but preferred occupying the upper forest belt between 3900 and 4200m asl year-round, being at the highest altitude in summer, the lowest altitude in spring, and middle altitudes between autumn and winter (lower in winter than autumn). Moreover, there were secondary peaks of lower altitude use (3700m) in spring and winter. In addition, more faeces were distributed in subvalleys than on subridges in winter, this suggests that monkeys tend to spend more time in subvalleys where there is less wind and fluctuating temperatures. The significant correlation between faecal density and lichen load might indicate that altitudinal distribution of food resources may act as an important factor affecting the monkeys' range. The monkeys might migrate to lower altitudes to eat young sprouts and leaves in spring, and to shelter from snowstorms in winter, possibly resulting in the secondary peaks at lower altitudes. 展开更多
关键词 Altitudinal range Faeces distribution Lichen abundance Rhinopithecus bieti Temperate primates
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Spatial distribution and abundance of small fishes in Xiaosihai Lake,a shallow lake along the Changjiang (Yangtze) River, China 被引量:5
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作者 李为 张堂林 李钟杰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第3期470-477,共8页
Spatial distribution and abundance of small fishes were studied in autumn 2007 in the Xiaosihai Lake, a shallow lake along the middle reach of the Changjiang (Yangtze) River. Based on the plant cover, the lake was d... Spatial distribution and abundance of small fishes were studied in autumn 2007 in the Xiaosihai Lake, a shallow lake along the middle reach of the Changjiang (Yangtze) River. Based on the plant cover, the lake was divided into three major habitats: Myriophyllum spicaturn habitat (MS habitat), Trapa bispinosa habitat (TB habitat), and non-vegetation habitat (NV habitat). A modified pop-net was used for quantitative sampling of small fishes in the three habitats, and the Zippin's removal method was used for estimating densities of the small fishes. A total of 13 species belonging to 5 families were collected, with 11 species in MS habitat, 7 species in TB habitat, and 5 species in NV habitat. Habitat type had significant effect on the spatial distribution of small fishes. The Shannon-Wiener diversity index in the MS, TB and NV habitats were 1.28, 0.56 and 0.54, respectively. The total density and biomass of small fishes were significantly higher in the MS habitat (13.68 ind/m^2 and 4.44 g/m^2) than in the TB habitat (1.41 ind/m^2 and 0.54 g/m^2) and the NV habitat (1.08 ind/m^2 and 0.40 g/m^2), and were not significantly different between the TB habitat and the NV habitat. Water depth had no significant effect on spatial distribution of the small fishes. It was suggested that vegetation type played an important role in habitat selectivity of small fishes, and the presence of submersed vegetation should be of significance in the conservation of small fish diversity. 展开更多
关键词 small fishes spatial distribution abundance estimation habitat selectivity Xiaosihai Lake
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Effects of an artificial reef system on demersal nekton assemblages in Xiangshan Bay, China 被引量:9
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作者 姜亚洲 林楠 +3 位作者 袁兴伟 焦海峰 申屠基康 李圣法 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2016年第1期59-68,共10页
In 2012,an artificial reef system was deployed in Xiangshan Bay,China,to enhance its fishery resources. To determine the effect of the artificial reef system on the demersal nekton assemblages,a beforeafter-control-im... In 2012,an artificial reef system was deployed in Xiangshan Bay,China,to enhance its fishery resources. To determine the effect of the artificial reef system on the demersal nekton assemblages,a beforeafter-control-impact study design was applied. Comparisons of assemblages from impact and control habitats revealed that the assemblage in the impact area had a gradual response to reef deployment. The assemblages in the impact and control areas changed in different ways after reef deployment. During the study period,total biomass,species richness and average body weight in the control area remained relatively stable,whereas there were significant increases in these indicators in the impact area. Responses to the reefs differed among nekton species,inducing assemblage succession in the reefs post-deployment. Sparus macrocephalus and Cynoglossus abbreviat us benefited most from reef deployment. Conversely,smallsized shrimp Palaemon gravieri showed a progressive decrease in biomass following reef deployment. Overall,the artificial reef system diversified the demersal nekton assemblage,enhanced the total biomass,and increased the proportion of large-sized species. 展开更多
关键词 artificial reefs nekton assemblage before-after-control-impact Xiangshan Bay
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Species Richness and Diversity of Alpine Grasslands on the Northern Tibetan Plateau:Effects of Grazing Exclusion and Growing Season Precipitation 被引量:10
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作者 武建双 张宪洲 +4 位作者 沈振西 石培礼 余成群 宋明华 李晓佳 《Journal of Resources and Ecology》 CSCD 2012年第3期236-242,共7页
Species richness and diversity indices (Shannon-Wiener index, Simpson dominance index and Pielou evenness index) in alpine grassland ecosystems (alpine meadow, alpine steppe and desert steppe) under grazing-exclud... Species richness and diversity indices (Shannon-Wiener index, Simpson dominance index and Pielou evenness index) in alpine grassland ecosystems (alpine meadow, alpine steppe and desert steppe) under grazing-excluded and freely grazed sites were investigated along the Northern Tibetan Plateau Alpine Grassland Transect during summer 2009 and 2010. We found that species richness and diversity have not been significantly altered by short-term grazing exclusion since 2006 at vegetation and regional scales. Species richness and diversity were mainly driven by growing season precipitation (GSP), which accounted for over 87 % of the total variation observed, Species richness and diversity at grazing- excluded and freely grazed sites appear to respond to growing season precipitation in parallel. Species richness exponentially increased with GSP while diversity indices showed positively linear relationships with GSP. This indicates that GSP on the Northern Tibetan Plateau is crucial in regulating species richness and diversity and should be taken into account in future studies on alpine grassland conservation. 展开更多
关键词 species diversity species richness grazing exclusion growing season precipitation alpinegrasslands Northern Tibetan Plateau
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Contribution of Root Proliferation in Nutrient-Rich Soil Patches to Nutrient Uptake and Growth of Maize 被引量:19
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作者 LI Hong-Bo ZHANG Fu-Suo SHEN Jian-Bo 《Pedosphere》 SCIE CAS CSCD 2012年第6期776-784,共9页
Root proliferation can be stimulated in a heterogeneous nutrient patch; however, the functions of the root proliferation in the nutrient-rich soil patches are not fully understood. In the present study, a two-year fie... Root proliferation can be stimulated in a heterogeneous nutrient patch; however, the functions of the root proliferation in the nutrient-rich soil patches are not fully understood. In the present study, a two-year field experiment was conducted to examine the comparative effects of localized application of ammonium and phosphorus (P) at early or late stages on root growth, nutrient uptake, and biomass of maize (Zea mays L.) on a calcareous soil in an intensive farming system. Localized supply of ammonium and P had a more evident effect on shoot and root growth, and especially stimulated fine root development at the early seedling stage, with most of the maize roots being allocated to the nutrient-rich patch in the topsoil. Although localized ammonium and P supply at the late stage also enhanced the fine root growth, the plant roots in the patch accounted for a low proportion of the whole maize roots in the topsoil at the flowering stage. Compared with the early stage, fine root length in the short-lived nutrient patch decreased by 44%-62% and the shoot dry weight was not different between heterogeneous and homogeneous nutrient supply at the late growth stage. Localized supply of ammonium and P significantly increased N and P accumulation by maize at 35 and 47 days after sowing (DAS); however, no significant difference was found among the treatments at 82 DAS and the later growth stages. The increased nutrient uptake and plant growth was related to the higher proportion of root length in the localized nutrient-enriched patch. The results indicated that root proliferation in nutrient patches contributed more to maize growth and nutrient uptake at the early than late stages. 展开更多
关键词 biomass growth stage intensive farming system localized nutrient supply root length
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Carbon isotope fractionation during CH_4 transport in paddy fields 被引量:1
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作者 ZHANG GuangBin JI Yang +2 位作者 LIU Gang MA Jing XU Hua 《Science China Earth Sciences》 SCIE EI CAS 2014年第7期1664-1670,共7页
In this study,to further promote the application of the stable carbon isotope natural abundance(SCINA)method to the study of CH4in paddy fields in China,field experiments were carried out to investigate carbon isotope... In this study,to further promote the application of the stable carbon isotope natural abundance(SCINA)method to the study of CH4in paddy fields in China,field experiments were carried out to investigate carbon isotope fractionation during CH4transport in both rice-and non-rice-growing seasons.More importantly,two new methods for the measurement of the CH4transport fractionation factor(εtransport)in paddy fields were introduced.The results indicated that the closed chamber+syringe method was much better for the determination ofεtransport during the non-rice-growing season.Presently,εtransport was calculated using theδ13C value of the CH4emitted from a rice field minus that of the CH4in the floodwater(–6.7‰to–3.0‰).In addition,there were three methods available for estimatingεtransport during the rice-growing season:deduction of theδ13C value of the CH4in the floodwater from that of the CH4emitted from the field(–16.6‰to–15.2‰);deduction of theδ13C value of the CH4in the soil pore water from that of the CH4emitted from the field(–13.2‰to–1.1‰);and deduction of theδ13C value of the CH4in the aerenchyma of plants from that of the CH4emitted from plants(–16.3‰to–10.9‰).Unfortunately,the first two methods showed relatively large uncertainties.Only the last one,the dividing+cutting method,was not only scientific and reliable but also provided accurate measurements. 展开更多
关键词 paddy field CH4 transport isotope fractionation factor closed chamber syringe method dividing cutting method
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