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新疆阿尔泰山两河源自然保护区湿地资源评价 总被引：1，自引：0，他引：1
新疆阿尔泰山两河源自然保护区位于阿勒泰地区富蕴县和青河县境内,有非常丰富的湿地资源及动植物资源。保护区湿地资源面积有1.51万hm2,有供水与蓄水、涵养水源与调蓄洪水、固碳释氧、保育土壤、生物多样性、栖息地、生态旅游、科研文化等重要功能,对维持阿尔泰山地区生态平衡有很重要的作用。 相似文献
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<正>阿尔泰山脉位于中国新疆北部和蒙古西部。中国境内的阿尔泰山属中段南坡,森林资源丰富,是典型的泰加林。泰加林带是指从北极苔原南界树木线开始,向南延伸1000多公里宽的北方塔形针叶林带,是世界上最大的而且也是独具北极寒区生态环境的森林带类型。这里分布着着广袤的寒温带针叶林、亚高山草甸和山地苔原,欧亚草原带上的物种以及环北极分布的物种在阿尔泰山交会。独特的地理、气候和生物环境,使得这里蕴藏着极富异域风情的花卉鸟兽。对于鸟类 相似文献
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K. Gadek 《Journal of pest science》1963,36(5):67-70
Summary In Central Poland in Saint Cross Mountains (Góry Swiętokrzyskie) from 1948 takes place a mass appearance of fir budwormChoristoneura murinana Hb. on the area of 2168 ha (8700 acres). Morever it accures over thereErnarmonia (Zeiraphera) rufinitrana HS,Eucosma (Epiblema) nigricana HS and others.
The author performed from 1957 detailed investigations concerning these pests. In the present paper he discussed history of
present attacks of the pests in Poland, as well as causes of mass appearance and economic significance of damages, listed
species of accompanying insects as well as methods of prognosis.
On the area of mass appearance the author conducted investigations concerning biology and ecology of the pests, inquired conditions
of development of mass increase and experiments of chemical and biological fight.
On this area there are conducted also pedological, typological, phenological and biometric studies. The task of these studies
is to explain the causes of rise of mass appearance of these insects and elaboration of preventing means.
Résumé Dans le territoire de la Pologne Centrale sur le terrain des Monts Sainte Croix a lieu à partir de l'année 1948 la gradation (apparition en masse) de la tordeuse du sapin(Choristoneura murinana Hb.) sur la surface de 2168 hectares. L'Ernarmonia (Zeiraphera) rufimitrana H. S., l'Eucosma (Epiblema) nigricana H. S. et autres y paraissent aussi. A partir du 1957 l'auteur conduit des recherches détaillées sur ce nuisible insecte. Il a discute dans un article l'histoire des gradations précédentes de ces insectes en Pologne, causes des origines des gradations, importance économique par rapport aux dommages occasionnés, ainsi que les espéces des insectes accompagnat les tordeuses du sapin et les méthodes de la prognose. Dans les terrains de la gradation l'auteur fait des observations concernant la biologie et l'écologie des insectes précites, explore les conditions des origines des gradations, fait des expériments de la lutte chimique pour les détruire complètement. On y conduit aussi des études du sol, ainsi que les études typologiques, biometriques, fénologiques et autres. Ces études ont pour but de pouvoir approfondir les causes d'origine des gradations ainsi que l'élaboration des mesures préventives.
Краткое содерж ание В сре дней Польше, на терри тории Свенто кшиских гор, имеет место, начин ая с 1948 г. массовое появление пихтовых листо верток, выступа ющих на площади 2168 га. Главным вредителем являетсяChoristoneura murinana Hb. — Кроме того появляютсяErnarmonia (Zeiraphera) rufimitrana H. S.,Eucosma (Epiblema) nigricana H. S. и другие. Автор ведет с 1957 г. подробнье иссле дования этих вре дителей. В своей статье даетист ориюпоя влений в Польше этих вредителей, имевших место до того времени, причины возникн овениям ассовых появлений, хозяйст венное значение причинен ныхубытков, роды насек омых, сопутст вующихл истоверткам, равно как метод прогноза ихпоявления. Автор ведет на террит ории массовото появления вредителей наблюдения над биологией и экологиейв редителей, изучает усл овия возникнове ниямассовых появлений, ведет опыты над химическойи биологи ческой борьбой с ними. На месте проводятся одновре менно исследо ванияпочвы, типологи ческие, биометри ческие, фенолог ическиеи другие испытания. Все привед енныеиспы тания имеют целью определить причинывоз никновения массовых появлений вредителейи разработать предохранит ельные меры. —相似文献
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A dramatic decline in forest cover in eastern Africa along with a growing population means that timber and poles for building
and fuelwood are in short supply. To overcome this shortage, the region is increasingly turning to eucalyptus. But eucalyptus
raises environmental concerns of its own. Fears that it will deplete water supply, affect wildlife and reduce associated crop
yields have caused many countries in the region to discourage farmers from planting this exotic. This paper is part of a series
of investigations on the growth and water use efficiency of faster growing eucalyptus hybrids, which was introduced from South
Africa to Kenya. The hypothesis is that the new hybrids are more efficient in using water and more suitable for the semi-arid
tropics than existing eucalyptus and two popular agroforestry species. Gas exchange characteristics of juvenile Eucalyptus grandis (W. Hill ex Maiden), two eucalyptus hybrids (E. grandis × Eucalyptus camaldulensis Dehnh.), Grevillea robusta (A. Cunn) and Cordia africana (Lam) was studied under field and pot conditions using an infrared gas analyzer was used to measure photosynthetic active
radiation (PAR), net photosynthetic rate (A), stomatal conductance (g
s) and transpiration rate (E) at CO2 concentrations of 360 μmol mol−1 and ambient humidity and temperature. A, E and g
s varied between species, being highest in eucalyptus hybrid GC 15 (24.6 μmol m−2 s−1) compared to eucalyptus hybrid GC 584 (21.0 μmol m−2 s−1), E. grandis (19.2 μmol m−2 s−1), C. africana (17.7 μmol m−2 s−1) and G. robusta (11.1 μmol m−2 s−1). C. africana exhibited high E values (7.0 mmol m−2 s−1) at optimal soil moisture contents than G. robusta (3.9 mmol m−2 s−1) and eucalyptus (5.3 mmol m−2 s−1) in field experiment and G. robusta (3.2 mmol m−2 s−1) and eucalyptus (4.2 mmol m−2 s−1) in pot-grown trees. At very low soil moisture content, extremely small g
s values were recorded in GC 15 and E. grandis (8 mmol m−2 s−1) and G. robusta (14 mmol m−2 s−1) compared to GC 584 (46.9 mmol m−2 s−1) and C. africana (90.0 mmol m−2 s−1) indicating strong stomatal control by the species. Instantaneous water use efficiency ranged between 3 and 5 μmol mmol−1 and generally decreased with decline in soil moisture in pot-grown trees but increased with declining soil moisture in field-grown
trees. 相似文献
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Veikko Kanervo 《Journal of pest science》1960,33(1):1-5
Zusammenfassung Einige der wichtigsten gegenwärtigen Probleme hinsichtlich der landwirtschaftlichen Schädlinge in Finnland sind folgende:Bei Getreide die Schäden durchCalligypona pellucida am Hafer sowie die Schäden durch die Fritfliege(Oscinella frit) an Saat von Winter- und Sommergetreide, die durch Blasenfüßer(Thysanoptera) u. a. Arten verursachte Weißährigkeit und Schmachtkörnigkeit, deren Bekämpfung noch nicht befriedigend entschieden ist. — Beim RotkleePhytonomus nigrirostris, Apion apricans undA. assimile, Sitona spp. undDitylenchus dipsaci, deren Biologie und Bekämpfung weiterhin fortgesetzt werden, — Bei ÖlpflanzenCeuthorrhynchus assimilis undC. quadridens sowieDasyneura brassicae, deren Bekä mpfung zu ermitteln ist. — Bei Zuckerrübe sowie einigen anderen Kulturpflanzen Bedeutung und Bekä mpfung vonLygus-Arten (besondersL. rugulipennis undL. pratensis). Bekämpfung der Rübenfliege(Pegomyia hyoscyami) bei Zuckerrübenkulturen. — Bei den Wurzelschädlingen von Gemüse und Hackfrüchten Klären von Biologie und Bekämpfung der Kohlfliegen (Hylemyia brassicae undH. floralis), der Fliegenschädlinge von Zwiebeln (Hylemyia antiqua, Eumerus tuberculatus undE. strigatus) und der Möhrenfliege. — Die Wirkung der Spritzungen in Obstgärten auf die wichtigsten Schä dlinge(Metatetranychus pilosus, Doralina pomi, Psylla mali, Carpocapsa pomonella, Argyresthia conjugella) und ihre wirksamsten Feinde.— In Beerengärten bei den ArtenTarsonemus fragariae, Eriophyes ribis undPachynematus pumilio sowie in Obstgärten bei der ArtAnisandrus dispar Intensivierung der Bekä mpfung. — Älchen(Anguillulidae), besondersdas Kleeälchen und Klärung von Lebensbedingungen und Bekämpfung desKartoffelälchens. — Bedeutung und Bekämpfung der Wühlmäuse (besondersMicrotus agrestis, M. arvalis undArvicola terrestris). — Untersuchung der Bedeutung von virusverbreitenden Insektenarten. — Erforschung der Nachteile von Bekämpfungsmitteln für die Pflanzen. 相似文献
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选取重庆缙云山的针阔混交林、常绿阔叶林、毛竹林、灌木林4种典型林分,观测酸性降水过程中林外雨、穿透雨及干流等林内水分转换分量中的主要离子含量变化,分析林分冠层对雨水化学组成的影响,结果表明:(1)降雨中的离子当量浓度大小依次是SO42-＞Ca2+＞ NH4+＞Mg2+＞K+＞Na+＞NO3-;(2)降雨经过林冠层后pH值降低,干流的酸化程度增加最大;(3)降雨经林冠层后离子浓度明显增加(除灌木林),穿透雨中通量增加最大的阴离子和阳离子分别为SO42-(2.19×103～6.47×103 eq·hm-2)和Ca2+(1.41×103～3.39×103 eq-hm-2),离子来源主要为大气沉降和植物分泌物或淋出;(4)同一离子在不同林分的干流和穿透雨中的通量变化不同,反映出不同林分冠层的离子交换性差异.在针阔混交林中,林下降雨净淋溶量大小顺序为SO42-＞Ca2+＞ NO3-＞K+＞NH4+＞Mg2+＞ Na+;常绿阔叶林为SO42-＞ Ca2+＞ K+＞NO3-＞ NH4+＞ Mg2+ ＞Na+;毛竹林为Ca2+＞ SO42-＞ K+＞NO3-＞ NH4+＞Na+＞Mg2+;灌木林为Ca2+＞ NO3-＞ K+＞ Na+＞Mg2+＞ NH4+＞ SO42-. 相似文献
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１９９８年４月至１９９９年３月对广州市白云山马尾松林和常绿阔叶林、广州市龙眼洞马尾松林两试验点进行了酸雨的监测,并测定和分析了林内穿透雨物理量及化学量,旨在探讨酸雨对不同森林冠层养分淋溶规律的影响。结果表明：（１）广州市酸雨占次数的７９．７％或占降雨量的９５．１％。（２）酸雨通过林冠层后,ｐＨ值明显增加。（３）在马尾松林和常绿阔叶林中,某些单次降雨出现ＳＯ４＾２－、ＮＯ３＾－、ＮＨ４＾＋Ａｌ＾３＋、Ｎａ＾＋的负淋溶现象,说明森林对这些离子（特别是ＮＯ３＾－、Ａａ＾３＋）具有吸收作用;阔叶林全年的ＮＯ３＾－和Ａｌ＾３＋净淋溶为负值,说明阔叶林比马尾松林对这两种离子具有更强的吸收能力。（４）雨水酸度增加（即ｐＨ值减小）,明显提高阳离子Ｃａ＾２＋、Ｍｇ＾２＋、Ｋ＾＋和Ｎａ＾＋冠层淋溶面分率。（５）ＮＨ４＾＋、ＳＯ４＾ 相似文献
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Tomohito Sano Takashi Hirano Naishen Liang Ryuichi Hirata Yasumi Fujinuma 《Forest Ecology and Management》2010
A typhoon event catastrophically destroyed a 45-year-old Japanese larch plantation in southern Hokkaido, northern Japan in September 2004, and about 90% of trees were blown down. Vegetation was measured to investigate its regeneration process and CO2 flux, or net ecosystem production (NEP), was measured in 2006–2008 using an automated chamber system to investigate the effects of typhoon disturbance on the ecosystem carbon balance. Annual maximum aboveground biomass (AGB) increased from 2.7 Mg ha−1 in 2006 to 4.0 Mg ha−1 in 2007, whereas no change occurred in annual maximum leaf area index (LAI), which was 3.7 m2 m−2 in 2006 and 3.9 m2 m−2 in 2007. Red raspberry (Rubus idaeus) had become dominant within 2 years after the typhoon disturbance, and came to account for about 60% and 50% of AGB and LAI, respectively. In comparison with CO2 fluxes measured by the eddy covariance technique in 2001–2003, for 4.5 months during the growing season, the sum of gross primary production (GPP) decreased on average by 739 gC m−2 (64%) after the disturbance, whereas ecosystem respiration (RE) decreased by 501 gC m−2 (51%). As a result, NEP decreased from 159 ± 57 gC m−2 to −80 ± 30 gC m−2, which shows that the ecosystem shifted from a carbon sink to a source. Seasonal variation in RE was strongly correlated to soil temperature. The interannual variation in the seasonal trend of RE was small. Light-saturated GPP (Pmax) decreased from 30–45 μmol m−2 s−1 to 8–12 μmol m−2 s−1 during the summer season through the disturbance because of large reduction in LAI. 相似文献
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Nitrogen leaching in response to increased nitrogen inputs in subtropical monsoon forests in southern China 总被引：1，自引：0，他引：1
Dissolved inorganic nitrogen (DIN) (as ammonium nitrate) was applied monthly onto the forest floor of one old-growth forest (>400 years old, at levels of 50, 100 and 150 kg N ha−1 yr−1) and two young forests (both about 70 years old, at levels of 50 and 100 kg N ha−1 yr−1) over 3 years (2004–2006), to investigate how nitrogen (N) input influenced N leaching output, and if there were differences in N retention between the old-growth and the young forests in the subtropical monsoon region of southern China. The ambient throughfall inputs were 23–27 kg N ha−1 yr−1 in the young forests and 29–35 kg N ha−1 yr−1 in the old-growth forest. In the control plots without experimental N addition, a net N retention was observed in the young forests (on average 6–11 kg N ha−1 yr−1), but a net N loss occurred in the old-growth forest (−13 kg N ha−1 yr−1). Experimental N addition immediately increased DIN leaching in all three forests, with 25–66% of added N leached over the 3-year experiment. At the lowest level of N addition (50 kg N ha−1 yr−1), the percentage N loss was higher in the old-growth forest (66% of added N) than in the two young forests (38% and 26%). However, at higher levels of N addition (100 and 150 kg N ha−1 yr−1), the old-growth forest exhibited similar N losses (25–43%) to those in the young forests (28–43%). These results indicate that N retention is largely determined by the forest successional stages and the levels of N addition. Compared to most temperate forests studied in Europe and North America, N leaching loss in these seasonal monsoon subtropical forests occurred mainly in the rainy growing season, with measured N loss in leaching substantially higher under both ambient deposition and experimental N additions. 相似文献
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《Fitoterapia》2014
Five new ursane-type triterpenoidal saponins (1–5), together with five known ones (6–10), were isolated from the EtOH extract of the roots of Ilex cornuta. The structures of saponins 1–5 were elucidated as 19α-hydroxyurs-12-en-28-oic acid 3β-O-β-D-glucuronopyranoside (1), 19α-hydroxyurs-12-en-28-oic acid 3β-O-β-D-glucuronopyranoside-6-O-ethyl ester (2), 19α-hydroxyurs-12-en-28-oic acid 3β-O-α-L-arabinopyranosyl-(1 → 2)-β-D-glucuronopyranoside (3), 3β-O-[α-L-arabinopyranosyl-(1 → 2)-β-D-glucuronopyranosyl]-19α-hydroxyurs-12-en-28-oic acid 28-O-β-D-glucopyranosyl ester (4) and 3β-O-[α-L-arabinopyranosyl-(1 → 2)-β-D-glucuronopyranoside-6-O-methyl ester]-19α-hydroxyurs-12-en-28-oic acid 28-O-β-D-glucopyranosyl ester (5), on the basis of spectroscopic analyses (IR, ESI-MS, HR-ESI-MS, 1D and 2D NMR) and chemical reactions. Protective effects of compounds 1–10 against H2O2-induced H9c2 cardiomyocyte injury were tested. Compounds 1–5, 7, and 10 showed cell-protective effects. Among them compound 5 exhibited the highest activity. No significant DPPH radical scavenging activity was observed for compounds 1–10. 相似文献
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Canker disease of willow and poplar caused by Cryptosphaeria pullmanensis recorded in China 
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下载免费PDF全文 A new canker disease of Salix alba and Populus alba has been observed in Xinjiang, China. Black circular spots on dead branches and stems are the symptoms of the disease. Sixty‐seven isolates recovered from Salix matsudana, S. alba and Populus alba were identified as Cryptosphaeria pullmanensis based on morphological features and multigene phylogeny. Pathogenicity tests were performed on S. alba and P. alba stems using the C. pullmanensis isolates. Cankers on and Cryptosphaeria pullmanensis of C. pullmanensis from the stems fulfilled Koch's postulates and confirmed C. pullmanensis as the causal agent of the canker disease. C. pullmanensis is characterized by its yellow stromatic tissue surrounded by a black conceptacle with regularly arranged multiple locules sharing common walls and hyaline, allantoid, aseptate conidia (mean size 7.42 × 1.72 μm). This is the first report of C. pullmanensis causing Cryptosphaeria canker in China, and S. alba and P. alba are new host records for C. pullmanensis. 相似文献
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This study was conducted to determine carbon (C) dynamics following forest tending works (FTW) which are one of the most important forest management activities conducted by Korean forest police and managers. We measured organic C storage (above- and below-ground biomass C, forest floor C, and soil C at 50 cm depth), soil environmental factors (soil CO2 efflux, soil temperature, soil water content, soil pH, and soil organic C concentration), and organic C input and output (litterfall and litter decomposition rates) for one year in FTW and non-FTW (control) stands of approximately 40-year-old red pine (Pinus densiflora S. et Z.) forests in the Hwangmaesan Soopkakkugi model forest in Sancheonggun, Gyeongsangnam-do, Korea. This forest was thinned in 2005 as a representative FTW practice. The total C stored in tree biomass was significantly lower (P < 0.05) in the FTW stand (40.17 Mg C ha−1) than in the control stand (64.52 Mg C ha−1). However, C storage of forest floor and soil layers measured at four different depths was not changed by FTW, except for that at the surface soil depth (0–10 cm). The organic C input due to litterfall and output due to needle litter decomposition were both significantly lower in the FTW stand than in the control stand (2.02 Mg C ha−1 year−1 vs. 2.80 Mg C ha−1 year−1 and 308 g C kg−1 year−1 vs. 364 g C kg−1 year−1, respectively, both P < 0.05). Soil environmental factors were significantly affected (P < 0.05) by FTW, except for soil CO2 efflux rates and organic C concentration at soil depth of 0–20 cm. The mean annual soil CO2 efflux rates were the same in the FTW (0.24 g CO2 m−2 h−1) and control (0.24 g CO2 m−2 h−1) stands despite monthly variations of soil CO2 efflux over the one-year study period. The mean soil organic C concentration at a soil depth of 0–20 cm was lower in the FTW stand (81.3 g kg−1) than in the control stand (86.4 g kg−1) but the difference was not significant (P > 0.05). In contrast, the mean soil temperature was significantly higher, the mean soil water content was significantly lower, and the soil pH was significantly higher in the FTW stand than in the control stand (10.34 °C vs. 8.98 °C, 48.2% vs. 56.4%, and pH 4.83 vs. pH 4.60, respectively, all P < 0.05). These results indicated that FTW can influence tree biomass C dynamics, organic C input and output, and soil environmental factors such as soil temperature, soil water content and soil pH, while soil C dynamics such as soil CO2 efflux rates and soil organic C concentration were little affected by FTW in a red pine stand. 相似文献