The marine East Indies: diversity and speciation

Aim To discuss the impact of new diversity information and to utilize recent findings on modes of speciation in order to clarify the evolutionary significance of the East Indies Triangle. Location The Indo‐Pacific Ocean. Methods Analysis of information on species diversity, distribution patterns and speciation for comparative purposes. Results Information from a broad‐scale survey of Indo‐Pacific fishes has provided strong support for the theory that the East Indies Triangle has been operating as a centre of origin. It has become apparent that more than two‐thirds of the reef fishes inhabiting the Indo‐Pacific are represented in the Triangle. An astounding total of 1111 species, more than are known from the entire tropical Atlantic, were reported from one locality on the small Indonesian island of Flores. New information on speciation modes indicates that the several unique characteristics of the East Indian fauna are probably due to the predominance of competitive (sympatric) speciation. Main conclusions It is proposed that, within the East Indies, the high species diversity, the production of dominant species, and the presence of newly formed species, are due to natural selection being involved in reproductive isolation, the first step in the sympatric speciation process. In contrast, speciation in the peripheral areas is predominately allopatric. Species formed by allopatry are the direct result of barriers to gene flow. In this case, reproductive isolation may be seen as a physical process that does not involve natural selection. Allopatric species formation often takes millions of years, while the sympatric process is generally much faster. Following species formation, dispersal from the East Indies appears to take place according to the centrifugal hypothesis.     

基于遥感和过程模型的亚洲东部陆地生态系统初级生产力分布特征

利用美国环境预测中心的再分析气象资料和由GIMMS NDVI 资料生成的叶面积指数对BEPS生态模型进行驱动,模拟分析了2000-2005年亚洲东部地区总初级生产力（GPP）和总净初级生产力（NPP）的时空变化特征.在进行区域模拟计算前,使用15个站点不同生态系统的GPP观测数据及1300个样点的NPP观测数据对模型进行验证.结果表明： BEPS模型能较好地模拟不同生态系统的GPP和NPP变化,模拟的GPP与观测数据之间的R2为0.86～0.99,均方根误差（RMSE）为0.2～1.2 g C·m-2·d-1;BEPS模拟值能够解释78%的年NPP变化,其RMSE为118 g C·m-2·a-1.2000-2005年,亚洲东部地区GPP和NPP总量平均值分别为21.7和10.5 Pg C·a-1.NPP和GPP具有相似的时空变化特征.研究期间,NPP总量的变化范围为10.2～10.7 Pg C·a-1, 变异系数为2.2%.NPP由东南向西北显著减少,高值区〖JP2〗（>1000 g C·m-2·a-1）出现在东南亚海岛国家,我国的西北干旱沙漠地区为低值区（<30 g C·m-2·a-1）,〖JP〗其空间格局主要由气候因子决定.不同国家的人均NPP差异很大,其中,蒙古最高,达70217 kg C·a-1,远高于中国的人均NPP（1921 kg C·a-1）,印度的人均NPP最小,为757 kg C·a-1.     

Causal analysis of the diversity of medusae in East China Sea

Based on the maritime data collected from 23°30′–33°00′ N and 118°30′–128°00′ E of the East China Sea (ECS) in four seasons during 1997–2000, the dynamics of medusae diversity and their causes were analyzed. A total of 103 medusae species were identified, and these species mainly distributed in the southern and northern offshore areas of the ECS. Species diversity index (H′) of medusae was higher in the south than those in the north, higher in summer and winter than in spring and autumn, and higher in offshore than in the nearshore areas. The species number was closely correlated with H′ value, whereas the abundance of species had no significant relationship with the diversity index. The lower H′ value of the nearshore in spring and autumn resulted from the aggregation of Muggiaea atlantica in the south nearshore and Diphyes chamissonis in the north nearshore. In addition, water temperature, followed by salinity, is the main environmental factor influencing the distribution of species diversity. The H′ value was related to the water temperature at the 10 m layer in winter and spring, and it was associated with the surface water temperature in summer and with the 10 m-salinity-layer in autumn. In spring and summer, the isoline distribution of H′ value reflected the direction of the Taiwan Warm Current and the variation of the water masses in the ECS. In winter, the isoline of the H′ value indicated the incursion of Kuroshio current. In conclusion, the H′ isoline is an good indicator for water masses in ECS. __________ Translated from Biodiversity Science, 2006, 14(6): 508–516 [译自:生物多样性]     

1989-2011年东洞庭湖草洲出露面积变化及其与水位响应的关系

基于多时相的Landsat MSS/TM/ETM⁺遥感影像数据,采用决策树分类法提取1989-2011年共49景东洞庭湖不同水位条件下的草洲出露面积,结合1985-2011年城陵矶日水位数据及数字高程模型,分析草洲时空变化特征并阐明其变化趋势.结果表明: 研究区出露草洲面积受水位影响显著,两者呈极显著的线性关系(R²=0.875,P<0.001),出露草洲面积随水位的升高而逐渐减小,且水位越高,对草洲出露面积的影响越小.草洲出露面积随水位呈现规律性变化,1-7月,水位上升,草洲面积减少;7-12月,水位下降,草洲出露面积增加.1989-2011年,草洲出露面积持续增加,新增草洲主要由泥滩地转化而来;草洲扩张是各高程段草洲面积共同增加的结果,低位洲滩(黄海高程22～25 m)草洲面积的快速增加是湿地草洲扩张的主导部分.各高程水位变化是研究期间东洞庭湖草洲出露面积变化的主要原因.     

Behavioral indices of estrus in a group of captive African elephants (Loxodonta africana)

This study investigated behavioral signals of estrus by systematically monitoring the interactions of one male with four female African elephants housed in a naturalistic outdoor enclosure at Disney's Animal Kingdom over a period of 11 months. We measured changes in five spatial behaviors and 22 tactile‐contact behaviors, as well as changes in serum progestagen and LH concentrations, across three ovarian cycles for each female. Two females did not cycle during the study. Three different phases of the ovarian cycle were identified: mid luteal, anovulatory follicular, ovulatory follicular. The male followed more and carried out more genital inspections, flehmen, and trunk‐to‐mouth behaviors toward cycling females during their ovulatory phase. Genital inspections by the male peaked above baseline levels on the day of an LH surge, and up to 9 days before, in both cycling females and, thus, might be a useful behavioral index of estrus. The male also carried out more genital inspections, flehmen, and trunk touches to the back leg toward ovulatory cycling than noncycling females. Overall, our results indicated that: 1) a single subadult African elephant male could discriminate two females in the ovulatory phase of their cycle (i.e., during the 3 weeks preceding ovulation) from the mid luteal phase; 2) the male also discriminated two cycling females in the ovulatory and anovulatory follicular phases from two noncycling females; 3) two females in the ovulatory phase of the cycle displayed a greater variety of tactile‐contact behavior toward the male compared to the other cycle phases. Zoo Biol 0:1–19, 2005. © 2005 Wiley‐Liss, Inc.     

Foraging strategies involved in habitat use of shorebirds at the intertidal area of Chongming Dongtan, China

Dense flocks of migratory shorebirds from diverse species often concentrate in the intertidal areas for stopover. Trophic structure, food partition, prey availability and selectivity, predation risk, and abiotic factors are often used to explain the differences in habitat use of coexisting shorebirds. We sampled the macrobenthos and surveyed the distribution of shorebird populations to study the effects of foraging strategies on the habitat use of shorebirds at Chongming Dongtan, an important stopover site for shorebirds on the East Asian–Australasian Flyway. Results show that the relative abundance of epifaunal macrobenthos in salt marshes was much higher than that in the bare flats, whereas the relative abundance of infaunal macrobenthos in salt marshes was much lower than that in bare flats. The relative abundance of two life forms of macrobenthos was similar in the transitional zones between the salt marshes and the bare flats. Shorebirds with different foraging strategies exhibited different habitat uses. Pause-travel shorebirds mainly utilized the salt-marsh fringes, while tactile continuous shorebirds relied heavily on the bare flats. There was no significant difference in habitat use for visual continuous shorebirds. The density of tactile continuous shorebirds was positively correlated with bivalve density, and that of visual continuous shorebirds positively with crustacean density. Meanwhile, the relative abundance of pause-travel foraging shorebirds was positively correlated with the relative abundance of epifaunal, but negatively with infaunal macrobenthos. In contrast, the relative abundance of tactile foraging shorebirds had a positive correlation with infaunal but a negative one with epifaunal life form. Therefore, foraging strategies may play important roles in shorebirds’ habitat use in intertidal areas.     

Structural comparison of tropical montane rain forests along latitudinal and altitudinal gradients in south and east Asia

Geographical patterns of altitudinal zonation, floristic composition, and structural features of tropical montane rain forests were examined along latitudinal gradients in south and east Asia. On equatorial mountains, the tropical montane rain forests occur above 1000 m. Toward middle latitudes, they come farther down and reach sea level at c. 35° N. Thus, the forests are equivalent to the subtropical rain forests of the latitudinal, horizontal zonation series. They exhibit gradual changes in floristic composition and structure along both altitudinal and latitudinal gradients. On equatorial mountains, they are divided into three types, i.e. tropical lower montane, upper montane, and subalpine forests. The three tree regeneration types, having emergent, sporadic and inverse-J type stem-diameter class frequency distributions, coexist in the lower montane forests, but the upper and subalpine forests display only the inverse-J type species with a few species of the sporadic type. Toward the northern latitudinal limit, the distinction between the three tropical montane forest zones in equatorial mountains becomes less clear. This can be explained by temperature conditions: on equatorial mountains, a temperature sum of 85° C months which controls the upper limit of the lower montane forests, and a coldest month mean temperature of-1° C which controls the evergreen broad-leaved trees, appear at c. 2500 and c. 4000 m respectively. The altitudinal range between 2500 m and 3800 m, which is the upper forest limit, is covered by upper montane and subalpine forests. On the other hand, at the latitudinal northern limit, the tropical upper montane and subalpine forests cannot exist because the above mentioned two temperature conditions occur at nearly the same point. Thus, at the northern latitudinal limit of the tropical montane forests, the three zones of equatorial mountains amalgamate into a single subtropical lowland forest community. This is due to the seasonal temperature climate in middle latitudes in, e.g., central Japan and central China.A part of this paper was presented as an oral presentation at the Vth International Congress of Ecology, Yokohama 23–30.8.1990.     

环柄菇属东亚一新记录种——锥鳞环柄菇

报道东亚环柄菇属的—个新记录种——锥鳞环柄菇Lepota jacobi Vellinga ＆ Knudsen,标本采自中国云南。该种的鉴别特征是菌盖密被灰色至暗褐色的锥状鳞片;担孢子椭圆形,腹部近平直,极小;囊状体缺如。     

华东区系鼠尾草属药用植物资源

通过资料查阅和标本查证,对华东区系野生鼠尾草属种类及药用植物资源进行调查研究。结果表明,华东区系现有鼠尾草属植物29种9变种4变型,其中具有药用价值的有15种3变种2变型。同时整理了这些药用鼠尾草植物的地理分布、生境特点,并制定了植物分种检索表。     

从生态地理特征论中国东北样带(NECT)在全球变化研究中的科学意义

中国东北样带(NECT)是国际地圈生物圈计划(IGBP)全球变化研究的陆地样带之一。该样带在东经112°与130°30′之间沿北纬43°30′设置,长约1600km,跨越北纬42°～46°,宽约300km,位于中纬度温带地区以降水或湿润度/干燥度为主要全球变化驱动因素,自东至西沿一个连续的空间过渡梯度,植被类型或生物群区是由温带针阔叶混交林、温带落叶阔叶林、农田及温带草原的3个亚地带:草甸草原、典型草原和荒漠草原等类型组成。给出了样带的基本生态地理特征及其梯度分析,包括其地理位置、地形地貌、气候梯度、土壤类型、土地利用格局、植被类型、主要优势种和群落类型的生态地理特征以及全新世适宜期的植被分布格局。这些特征沿经向均表现出明显的梯度分布。