Accurate measurement of optical properties of narrow leaves and conifer needles with a typical integrating sphere and spectroradiometer

Accurate information on the optical properties (reflectance and transmittance spectra) of single leaves is important for an ecophysiological understanding of light use by leaves, radiative transfer models and remote sensing of terrestrial ecosystems. In general, leaf optical properties are measured with an integrating sphere and a spectroradiometer. However, this method is usually difficult to use with grass leaves and conifer needles because they are too narrow to cover the sample port of a typical integrating sphere. Although ways to measure the optical properties of narrow leaves have been suggested, they have problems. We propose a new measurement protocol and calculation algorithms. The protocol does not damage sample leaves and is valid for various types of leaves, including green and senescent. We tested our technique with leaves of Aucuba japonica, an evergreen broadleaved shrub, and compared the spectral data of whole leaves and narrow strips of the leaves. The reflectance and transmittance of the strips matched those of the whole leaves, indicating that our technique can accurately estimate the optical properties of narrow leaves. Tests of conifer needles confirmed the applicability.     

Long‐term isolation of the coastal plant Calystegia soldanella (Convolvulaceae) in ancient freshwater Lake Biwa,Japan

Lake Biwa is an ancient freshwater lake that was formed approximately 4 Mya and harbours many coastal plants that commonly inhabit the seashore. We used chloroplast DNA haplotype analysis using two spacer sequences and simple sequence repeat (SSR) analysis using eight nuclear microsatellite markers to detect genomic signatures indicating long‐term isolation of inland populations of Calystegia soldanella in Lake Biwa from coastal populations. We used 348 samples from 63 populations for haplotype analysis and 478 samples from 27 populations for SSR analysis covering the inland and coastal distribution of the species. We detected seven haplotypes, and the distribution pattern of these haplotypes was geographically highly structured between Lake Biwa and the coast. Nuclear SSR analysis also supported genetic differentiation between Lake Biwa and coastal populations (analyses of molecular variance, 43%), and the grouping of Lake Biwa and coastal populations by a Neighbour‐joining tree. In addition, genetic diversity of the inland populations (mean H_E = 0.153) was significantly lower than that of coastal populations (mean H_E = 0.328). These results suggested that inland populations at Lake Biwa have been isolated from coastal populations for a very long time. The inland populations most likely experienced a bottleneck effect, resulting in sufficient in situ genetic divergence to clearly distinguish them from coastal populations. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 102 , 51–66.     

Habitat‐related patterns in phenotypic variation in a New Zealand freshwater generalist fish,and comparisons with a closely related specialist

1. Within‐species phenotypic variation is hugely variable and may play a role in determining the range of habitats a species can exploit. Our study addressed two main questions: 1. does phenotypic variation allow some species (i.e. habitat‐generalists) to use heterogeneous habitats and 2. are habitat‐generalists more variable than species occupying relatively homogeneous environments (i.e. habitat‐specialists)? 2. We examined the morphology of the common bully (Gobiomorphus cotidianus), a habitat‐generalist eleotrid fish found in lakes and rivers throughout New Zealand. We also compared the level of morphological variability in common bullies with that in the closely related redfin bully (Gobiomorphus huttoni), a habitat‐specialist of moderate‐ and fast‐flowing rivers. 3. Common and redfin bullies were collected from the South Island of New Zealand. A series of body and fin measurements were made, and cephalic dorsal head pores of the mechanosensory lateral‐line system were counted. The pores and associated canal neuromasts are important for prey detection and predator avoidance in other species, particularly, in turbulent conditions where the effectiveness of superficial neuromasts may be compromised. 4. The common bully had more dorsal head pores in fish from rivers than in those from lakes. This pattern was apparent only in adults, suggesting that selective pressures associated with adult habitat, be it rivers or lakes, are responsible. 5. As expected, there was greater phenotypic variability in the generalist common bully than in the specialist redfin bully, particularly with regard to the sensory pores, suggesting their importance for survival in turbulence. 6. We identified habitat‐related patterns in phenotypic variability in a generalist species and demonstrated a link between phenotypic variability and habitat breadth. Variation in the common bully may explain its ability to occupy a range of habitats.