Wanglang Nature Reserve Research Articles

海拔对岷山大熊猫主食竹营养成分和氨基酸含量的影响

PDF HTML阅读 XML下载 导出引用 引用提醒 海拔对岷山大熊猫主食竹营养成分和氨基酸含量的影响 DOI: 10.5846/stxb201607221496 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金面上项目（31270650）。 Effects of different altitudes on the nutrient and amino acid contents of bamboo (Fargesia denudata), staple food of the giant panda, in Minshan, Sichuan, China Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:缺苞箭竹（Fargesia denudata）是岷山山系大熊猫的主食竹，其可食性在大熊猫食物营养质量评价中具有重要意义。为揭示海拔梯度上温差对大熊猫主食竹营养成分及其含量的影响，以自然生长在岷山山系核心区四川王朗国家级自然保护区不同海拔（2600、2850、3100 m）的缺苞箭竹为对象，对其笋、秆和叶的营养成分和氨基酸含量进行了研究。结果表明：（1）同一海拔缺苞箭竹的粗蛋白和粗脂肪含量均表现为叶 > 笋 > 秆，且笋、秆和叶的营养成分含量有显著差异（P < 0.05）；（2）粗蛋白和氨基酸总量随海拔升高而显著增加（P < 0.05），而对粗脂肪和粗纤维的影响不显著（P > 0.05）；（3）除笋中苏氨酸、甘氨酸、半胱氨酸，秆中丝氨酸、蛋氨酸以及叶中半胱氨酸外，海拔对其余氨基酸含量均有显著影响（P < 0.05）；（4）海拔对粗蛋白/粗脂肪、粗蛋白/粗纤维有显著影响（P < 0.05），在笋和秆中表现为海拔3100 m最高，而海拔对纤维素/粗纤维、粗脂肪/粗纤维的影响不显著（P > 0.05）。缺苞箭竹叶、笋的营养成分含量明显高于秆；高海拔有利于缺苞箭竹各器官粗蛋白和氨基酸的积累，不利于粗纤维的积累，这可能使大熊猫的取食选择发生改变，更倾向于取食高海拔的笋和叶。 Abstract:Nutritional components of plant species (e.g., contents of crude protein, crude fat, and amino acids), as well as the contents of fiber that influence animals' food digestibility, collectively determine animal food preferences. Animals would prefer to feed on leaves or stems with higher contents of crude protein, crude fat, and amino acids and a lower content of fiber. Many studies have demonstrated that nutritional components or fiber contents are differently impacted by various environmental factors. It is possible that differences in the nutrient or fiber content of vegetation under different conditions would potentially affect animal distribution through food choice. Dwarf-bamboo species dominate the underground layer of subalpine forests. However, the distribution or growth of these bamboo species is predicted to be markedly affected by global warming. As the main food source for the panda, changes in temperature may influence their preference for bamboo by altering bamboo nutrition. Although the temperature difference along vertical altitudinal gradients is obvious, there have been few studies focusing on the effects of different temperatures on bamboo due to altitudinal gradients, which could potentially influence panda food preference and distribution. We designed an in situ experiment to examine the effects of different altitudes on the contents of nutrients, such as crude protein and amino acids, and parameters related to animal food digestibility, such as fiber content, of dwarf bamboo (Fargesia denudate) in Wanglang Nature Reserve in the northwest Sichuan Province, China. Samples (leaf, shoot, and culm) of F. denudata were selected from three altitudes (2600 m, 2850 m, and 3100 m) to study differences that may be attributable to differences in altitude. The results indicated that the nutrient compositions and amino acid contents of different parts of F. denudata showed different change patterns among the different altitudes. Our main results were as follows. (1) At the same altitude, nutrients of different F. denudata tissues (leaf, shoot, and culm) were significantly different from each other. For instance, the crude protein and crude fat contents of the leaf were the highest, whereas those of the stem were the lowest. In the shoot, these parameters were in the middle range. (2) Most interestingly, the amount of crude protein and total amino acids were markedly influenced by the altitudinal gradient, being significantly higher at 3100 m than at 2600 m. For example, the contents of crude protein and total amino acids of bamboo shoots were highest at 3100 m. However, crude fat and crude fiber showed no significant differences among the different altitudes. (3) In addition to the threonine, glycine, and cysteine in shoots, serine and methionine in culms, and cysteine in leaves, contents of the other amino acids were significantly affected by the altitudinal gradient. For example, the histidine content in shoots increased with increasing altitude. Altitude had significant effects on the ratios of crude protein/crude fat and crude protein/crude fiber; however, no significant effects were observed on the ratios of cellulose/crude fiber and crude fat/crude fiber. Our results demonstrate that at higher altitude, F. denudata accumulates higher contents of crude protein and total amino acids. Warmer climates would probably affect the distribution of F. denudata and characters related to panda food preference, such as crude protein content, which may, to a certain extent, determine panda movement or migration to higher altitudes to feed on relatively nutritious food. 参考文献 相似文献 引证文献

Habitat use by giant pandas (Ailuropoda melanoleuca) in relation to roads in the Wanglang Nature Reserve, People’s Republic of China

The impacts of roads on wildlife and their habitats have been widely recognized. To assess the effects of roads on habitat use of the giant panda (Ailuropoda melanoleuca (David, 1869)), we investigated the giant panda habitats and the roadside habitats in Wanglang Nature Reserve, People’s Republic of China. We found that giant pandas did not use the road-affected habitats, and compared with giant panda habitats, road-affected habitats were characterized by lower bamboo density and grazing disturbances. Therefore, our study demonstrated that roads negatively affected the habitat use of giant pandas, and such affected habitats could not meet the needs of these animals. These results suggest that to minimize the negative effects of roads on the conservation of species, a full evaluation of the effects of roads on wildlife and their habitats should be conducted before road construction, and effective protection measures should be taken to control for these negative effects.

Habitat use by giant panda in relation to man-made forest in Wanglang Nature Reserve of China.

To evaluate the effectiveness of human restoration in species conservation, in this study, we undertook a field survey of giant panda (Ailuropoda melanoleuca) habitat and man-made forest habitat in Wanglang Nature Reserve of China. Our results revealed that giant panda did not use the man-made forest in this area so far, and that there were significant differences between the giant panda habitat and the man-made forest habitat. Compared with giant panda habitat, the man-made forest habitat was characterized by lower shrub coverage, thinner trees and lower bamboo density. To improve the effectiveness of human restoration, the habitat requirement of giant panda should be fully consider in the whole process of habitat restoration.

Treeline dynamics in response to climate change in the Min Mountains, southwestern China.

BackgroundAbies faxoniana is the dominant plant species of the forest ecosystem on the eastern edge of Qinghai-Tibet Plateau, where the treeline is strongly defined by climate. The tree-ring chronologies and age structure of Abies faxoniana were developed in the treeline ecotones on the northwestern and southeastern aspects of the Min Mountains in the Wanglang Nature Reserve to examine the treeline dynamics of recent decades in response to climate change.ResultsOn the northwestern aspect, correlation analysis showed that the radial growth was significantly and positively correlated with precipitation in current January and monthly mean temperature in current April, but significantly and negatively correlated with monthly mean temperature in previous August. On the southeastern aspect, the radial growth was significantly negatively correlated with monthly mean temperature in previous July and August.ConclusionsThe different responses of radial growth to climatic variability on both the aspects might be mainly due to the micro-environmental conditions. The recruitment benefited from the warm temperature in current April, July and September on the northwestern aspect. The responses of radial growth and recruitment to climatic variability were similar on the northwestern slope. Recruitment was greatly restricted by competition with dense bamboos on the southeastern aspect.Electronic supplementary materialThe online version of this article (doi:10.1186/1999-3110-54-15) contains supplementary material, which is available to authorized users.

Microsatellite variability reveals the necessity for genetic input from wild giant pandas (Ailuropoda melanoleuca) into the captive population

Recent success in breeding giant pandas in captivity has encouraged panda conservationists to believe that the ex situ population is ready to serve as a source for supporting the wild population. In this study, we used 11 microsatellite DNA markers to assess the amount and distribution of genetic variability present in the two largest captive populations (Chengdu Research Base of Giant Panda Breeding, Sichuan Province and the China Research and Conservation Center for the Giant Panda at Wolong, Sichuan Province). The data were compared with those samples from wild pandas living in two key giant panda nature reserves (Baoxing Nature Reserve and Wanglang Nature Reserve). The results show that the captive populations have retained lower levels of allelic diversity and heterozygosity compared to isolated wild populations. However, low inbreeding coefficients indicate that captive populations are under careful genetic management. Excessive heterozygosity suggests that the two captive populations have experienced a genetic bottleneck, presumably caused by founder effects. Moreover, evidence of increased genetic divergence demonstrates restricted breeding options within facilities. Based on these results, we conclude that the genetic diversity in the captive populations is not optimal. Introduction of genetic materials from wild pandas and improved exchange of genetic materials among institutions will be necessary for the captive pandas to be representative of the wild populations.

Giant Panda Numbers Are Surging--or Are They?

WANGLANG NATURE RESERVE, CHINA-- Experts are sparring over a controversial count of wild pandas and plans to expand captive breeding of China9s revered symbol. (Read more.)

Effect of Couch Grass and Grass Cultivars on Competition Between Timothy and Red Clover

Based on the 1997-2009 inventory data of Wanglang Nature Reserve, the habitat selection attributes of giant panda were studied from the aspects of topography, forest community structure, and main feeding bamboo by the methods of frequency distribution and Bailey. The giant panda had obvious habitat preferences. Topographically, the preferred microhabitat was on the even or convex slopes at the ridge, top, or middle part of mountain body at an elevation 2500-3000 m, with southwest aspect, 6 degrees-30 degrees, and the distance to the nearest water source > 300 m. As for the forest community structure, the giant panda preferred the microhabitat with the bamboo succeeded from secondary forest or mixed conifer and broad-leaved forest, and with the average tree height being 20-29 m and the shrub coverage being 0-24%. The preferred main feeding bamboo by the giant panda was the growing well Fargesia denudate with an average height of 2-5 m and the coverage of > 50%.