中文摘要：

叶食性灵长类食物选择受食物常量营养物质、微量营养元素及其次生代谢产物等影响，但较少有研究阐释植物的化学成分效应。该研究通过分析拉沙山黑白仰鼻猴群春季（2010年3月-5月和2011年3月-5月）食物来阐明影响食物选择的植物化学成分。春季，猴群通过采食高质量食物（芽和嫩叶1来满足其营养需求，且偏好高磷和低钙／磷比（Ca／P）、低钙及低单宁食物。食物的磷和粗蛋白含量高于非食物，总糖和CWP低于非食物，而粗脂肪、粗灰分、钙和单宁含量则无差异；即在单宁含量未超过其忍受阈值的前提下，猴群春季食物选择原则是在满足蛋白质主导的常量营养物质需求基础上保证磷钙摄入。

英文摘要：

Food selection by folivorous primates is thought to relate to macronutrients, micronutrients and plant secondary metabolites. However, few studies explain their effects on food choices. This study was designed to clarify the effect of phytochemical components on Rhinopithecus bieti food choice by analyzing the chemical composition of food samples collected from March to May in 2010 and 2011 at Mt. Lasha in northwest Yunnan, China. Compared with non-foods, there was more phosphorous and crude protein, less total sugar and a lower ratio of calcium to phosphorus in selected foods. However, no differences were found in crude fat, crude ash, calcium and tannin content between foods and non-foods. Phytochemical constituents may influence food choices; the monkeys preferred foods with high phosphorus and low Ca/P, low calcium, low sugar and low tannins. Rhinopithecus bieti foraged high quality foods such as buds and young leaves to meet their nutritional needs after a long winter. Therefore, if tannin content in food did not exceed the enduring threshold of R. bieti, the nutrient intake was prioritized by phosphorus and calcium regulation when the need for macronutrients dominated by protein was satisfied.