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181.
Twelve novel microsatellite loci were isolated and characterized from enriched genomic libraries of Castanopsis chinensis. Four previously reported microsatellites from Castanopsis cuspidata were cross-amplified in C. chinensis. Forty-two sample trees from a wild population were tested for polymorphism using a set of the 16 polymorphic microsatellites. The average allele number of these microsatellites was 4.6 per locus, ranging from 2 to 7. The ranges of observed and expected heterozygosity were 0.262–1.000 and 0.238–0.818, respectively. Significant deviations from Hardy–Weinberg equilibrium were detected at five loci and no linkage disequilibrium was observed.  相似文献   
182.
Based on the animal dispersal hypothesis and the predator satiation hypothesis, we examined the effects of seed abundance at both population (i.e., mast seeding) and community levels on seed predation and dispersal of Castanopsis fargesii (Fagaceae), a rodent-dispersed mast species in Eastern Asia. In a subtropical evergreen broadleaved forest in the Dujiangyan region of Sichuan Province, China, individual seeds with coded tin tags were tracked in two contrasting stands (seed-poor and seed-rich) over two years (2000, a low-seed year; 2001, a high-seed year). Our results showed that: (1) small rodents did not harvest the tagged seeds of C. fargesii more rapid in the high-seed year than in the low-seed year in either stand. But, seed harvest was significantly faster in the seed-rich stand than in the seed-poor stand. (2) The removal proportion was significantly lower in the high-seed year than in the low-seed year for either stand, but the removal proportion was slightly higher in the seed-poor stand than in the seed-poor stand. This indicates that high seed abundance decreases seed removal (predator satiation hypothesis). (3) There were only small differences about seed caching, seed survival and seedling establishment of C. fargesii between years and stands. During the survey, no cached seeds survived to geminate in the spring for both stands and years. (4) Mean dispersal distances of the cached seeds are much shorter in the high-seed year (3.1 m) than in the low-seed year (8.1 m) in the seed-rich stand, though similar trend is not examined in the seed-poor stand. Our results indicate that seed predation and dispersal of C. fargesii are influenced by both mast seeding and community-level seed abundance, which is not completely consistent with either the animal dispersal hypothesis or the predator satiation hypothesis, but seems more related to the predator satiation hypothesis.  相似文献   
183.
184.
黄成就  张永田   《广西植物》1985,(3):183-184
<正> 龙州锥 (新种) 图版1 本种与淋漓锥近缘,但本种的叶片两面无毛且同色,叶缘有锯齿状裂齿,有时为钝裂齿,网状叶脉纤细而明显,果序较短,有果较少数,壳斗及坚果较大,壳斗的鳞片被毛,覆瓦状松弛排列,可作区别特征。 乔木,高5—8米,树干胸径8—15厘米,树皮灰棕色,当年生枝浑圆,粗壮,无毛,干后近暗棕色,密生淡黄色、细圆点状皮孔;新生芽阔卵形,顶端钝,长及宽均约3毫米,芽鳞无毛或边缘有稀疏短毛。叶硬报质,卵形,椭圆形或披针形,稀倒卵形,连叶柄长8—  相似文献   
185.
A. Miyawaki  Y. Sasaki 《Plant Ecology》1985,59(1-3):225-234
The forest vegetation of Japan can be classified into three major regions: (1) the Camellietea japonicae evergreen broad-leaved forest region, e.g. Laurel forest which can be compared with the sclerophyllous gorest (durilignosa sensu Rübel, 1930), in the Mediterranean region, (2) the Fagetea crenatae summergreen Broad-leaved forest region, (3) the Vaccinio-Piceetea japonicae subalpine and subboreal conifer forest region. The distribution of these forest types on the Japanese Islands is related to both the warmth index, WI, and to the coldness index, CI, after Kira (1945). The borderline between the evergreen Camellietea japonicae and the summergreen Fagetea crenatae in Japan almost coincides with the 85°C line of WI. The chorological ariation of the forest vegetation in Japan and Korea shows a close correlation with the amount of warmth in the actual vegetation season.The evergreen broad-leaved Castanopsis cuspidata var. sieboldii forests can be classified into three major alliances; Quercion acuto-myrsinaefoliae, Maeso japonicae-Castanopsion sieboldii, and Psychotrioastanopsion sieboldii.The distribution limit of these three alliances on the Japanese Islands is again related to temperature. Changes in temperature and latitude correspond closely to changes in the Evergreen Broad-leaved Forests long the Pacific Ocean coast of the Japanese Islands. The three forest alliances differ in their number of evergreen and deciduous broad-leaved woody species, secondary forest types and syndynamic processes.Contribution from the Department of Vegetation Science, Institute of Environmental Science and Technology, Yokohama National University, No. 154.  相似文献   
186.
The seasonal timing of flowering and fruiting is crucial for the reproductive success of plants and for resource availability to animals. Although plants synchronize their reproductive timing to coincide with appropriate seasons by responding to environmental cues, seasonal variations in temperature and precipitation vary minimally in very wet tropical environments. To explore the latitudinal cline in the reproductive phenology of the Fagaceae in Asia, we analyzed phenology data for a total of 94, 121, and 219 species from Thailand, Malesia, and China, respectively, in the three genera of Fagaceae, Quercus, Castanopsis, and Lithocarpus. We found that Quercus and Castanopsis showed flowering peaks in April in China. In Thailand, the peak shifted to an earlier month, and the peak disappeared in Malesia. The flowering period lengthened with decreasing latitude in the animal-pollinated genera Castanopsis and Lithocarpus. However, this was not the case for the wind-pollinated genus Quercus. The fruiting period lengthened with decreasing latitude in all three genera. We examined the relationship between reproductive phenology and climatic factors. The combination of monthly temperature and precipitation best explained the monthly change in the proportion of flowering and fruiting species in China in all three genera. However, climatic factors had almost no impact on the predictive ability of the model in Malesia. Our results on phenological shifts in the family Fagaceae, from the temperate climates and seasonal tropics to the humid tropics, provide valuable information for predicting phenological changes in future climate change.  相似文献   
187.
采用有限空间种群增长的逻辑斯谛模型探讨格氏栲种群基面积增长规律.提出自适应通用模型ds/dt=rs(1-sθ/kφ).该模型包括Logistic模型、Smith模型、Gompertz模型、崔Lawson模型和ZLogistic模型;运用改进单纯形对自适应通用模型进行优化,拟合结果比Logistic模型更符合格氏栲种群实际增长趋势,增长速度最大是在147年.  相似文献   
188.
黄成就  张永田   《广西植物》1996,16(4):300-302
新近国际植物命名法规指出,1990—01—01之后发表的属级及局级以下的新分类群必须注明主模式或模式标本的保存处才是合格发表。下述13个分类群在本文述及;其中2个分类群给予详细引证,1个杂种给予更确切的记述。  相似文献   
189.
壳斗科植物摘录(Ⅳ)   总被引:2,自引:0,他引:2  
黄成就  张永田   《广西植物》1990,10(1):1-10
<正> 乔木,高达25米,芽近圆球形,芽鳞阔卵形,被早脱落的棕色微柔毛,顶部边缘有红褐色蜡鳞,小枝干后黑褐色,密布微凸起的皮孔。叶近革质,卵状椭圆形或披针形,长10—15厘米,宽3.5—5厘米,顶部渐尖或尾状尖,基部一侧略短且偏斜,宽楔形或急尖,边全缘或近顶部边缘有1—3小裂齿,中脉在叶面凸起,侧脉每边9—12条,网状支脉纤细,新生嫩叶背面沿叶脉被疏长柔毛及散布暗灰色蜡鳞,叶柄长8—10毫米,幼嫩时被疏长柔毛及蜡鳞。雄花序为圆锥花序,花序轴被疏长毛及星芒状蜡鳞,花8—4朵一簇,雌花有花柱8  相似文献   
190.
Qiandao Lake was formed in 1959 when the Xin'anjiang Hydroelectric Plant was built. There are 1078 islands with areas larger than 2500 m2 and many smaller islands. The population structure of C. sclerophylla was investigated to reveal whether it can sustain on islands so as to provide suggestions for ecological restoration. C. sclerophylla can be found on islands with a water level higher than 105.4 m, whereas the highest water level of Qiandao Lake was 108.2 m. Number of individuals on islands, with a range from 4 to more than 4000, was significantly related to the areas or altitudes of the islands. Population structure indicated that, at genet level, C. sclerophylla on large and most medium-size islands could be self-sustainable, whereas on small and some medium-size islands C. sclerophylla could not be self-sustainable and would decline. However, at the ramet level, almost all the C. sclerophylla populations, no matter on large, medium or small islands, seem to be self-sustainable. Further analysis indicated that re-sprouting contributed to more than 81.6% of the genets and 94.8% of the shoots formed after the creation of the Lake. The results above indicated that although small size of populations exist on some islands, these populations might be sustained via vegetative reproduction, especially re-sprouting, for a long period under the present situation without human disturbance and dramatic environmental changes. Conditions of most islands meet the standards necessary for the survival and growth of C. sclerophylla. Therefore, lack of seed or seedling is the main limitation for the ecological restoration of evergreen broad-leaved forests on islands of Qiandao Lake. However, that no individual was reproduced from sexual reproduction on some medium and small islands indicates that environmental condition might be another limiting factor for restoration.  相似文献   
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