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1.
《Journal of bryology》2013,35(4):257-263
Abstract

South African populations of Bryobartramia have been treated as B. novae-valesiae, a species otherwise restricted to Australia. However, material from the two regions differs in a number of traits, and the African populations are here described as a new species, B. schelpei. The Cape species differs most obviously from B. novae-valesiae in the markedly prorate-papillose, narrow, thick-walled cells of the calyptra. Nested analysis of variance reveals further morphometric differences, including the relatively narrower, more cylindrical, calyptra with a longer rostrum, and the smaller leaf cells and spores. Bryobartramia schelpii is known only from arid portions of the winter rainfall region in the Northern and Western Cape Provinces of South Africa.  相似文献   

2.
王云霞  刘桂要  邓强  时新荣  袁志友 《生态学报》2020,40(19):6872-6884
凋落物分解是维持生态系统养分循环和能量流动的关键过程,但在雨热同期的黄土丘陵区,不同降雨时期凋落物基质质量动态对该区不同树种凋落物分解速率的影响还不清楚。采用凋落物分解袋法,基于野外原位分解实验分析黄土丘陵区主要人工林刺槐(Robinia pseudoacacia Linn.)和油松(Pinus tabulaeformis Carr.)凋落叶在不同降雨时期的分解特征和分解过程中凋落叶基质质量的变化与分解速率之间的关系。研究结果发现:(1)经过391 d的分解,刺槐凋落叶的平均质量损失速率为(51.0±8.44)mg/d,显著地高于油松凋落叶(36.7±4.83)mg/d;雨季期间两树种凋落叶的质量损失速率均显著地高于旱季,其中夏季多雨期间凋落叶的质量损失速率最高,冬季微量降雨期间质量损失速率最低。(2)在整个分解过程中两树种凋落叶C和N含量都表现为净释放且主要发生在雨季,P含量表现为释放与富集交替进行;刺槐凋落叶C/N比、C/P比和N/P比呈波动的趋势,油松凋落叶C/N比则显著地增加且在夏季多雨期出现峰值,C/P比呈波动的状态,N/P比变化较小。(3)不同降雨时期刺槐凋落叶的质量损失速率与凋落叶P含量动态显著正相关,与C含量、C/P比和N/P比动态显著负相关。油松凋落叶质量损失速率与C/N比动态显著正相关,与C、N含量动态显著负相关,与N/P比动态呈负二次函数的关系。这些结果说明黄土丘陵区刺槐和油松凋落叶在不同降雨时期分解速率之间的差异显著且两树种凋落叶的分解都集中在雨季期间;此外凋落叶分解主要受到凋落叶N含量和N/P比动态变化的制约,与刺槐凋落叶相比,N含量与N/P比对油松凋落叶的限制作用更强。  相似文献   

3.
Capelatus prykei gen. et sp.n. , a distinctive new lineage of copelatine diving beetle, is described from the greater Cape Town area of the Western Cape Province, South Africa, on the basis of both morphological and molecular data. The genus‐level phylogeny of Copelatinae is reconstructed using a combination of nuclear and mitochondrial DNA regions, demonstrating that Capelatus gen.n. has no close relatives within the Afrotropical region, instead forming a clade with the Palaearctic Liopterus and largely Australasian Exocelina. Capelatus gen.n. apparently represents a striking example of a phylogenetically isolated Cape lineage, which also appears to be narrowly endemic and endangered by ongoing habitat loss.  相似文献   

4.
Summary

The ocypodid genus Paratylodiplax was described in 1974 and contains four species, three of which are endemic to southern Africa where they form an important component of the estuarine benthic fauna. However, very little is known about the biology and ecology of the genus, with discrepancies existing between the commonly quoted distributions and actual records of the species. This comment outlines the current taxonomic status of the genus and attempts to resolve the discrepancies in the distributions of the southern African species Paratylodiplax blephariskios has been recorded from the Morrumbene estuary in Mozambique to the Mngazana estuary in the eastern Cape, while the distributions of P. algoensis and P. edwardsii are given as being from the Mngazana to the Eerste estuary and Langebaan Lagoon in the western Cape respectively.  相似文献   

5.
Summary

A temporary pool in a dry stream bed traversing Grootvloer Pan in the Northern Cape was inhabited by fifteen branchiopod and calanoid copepod crustacean species. There was an unusually high number of congeneric species in the pool; in the class Branchiopoda, five Streptocephalus species and four Daphnia species were collected. In addition, two species of the calanoid genus Metadiaptomus were identified. The high species richness was not related to habitat diversity, pool size or difference in body size of each species. Three species (Streptocephalus purcelli, S. gracilis and Metadiaptomus capensis) had previously been collected only from the winter-rainfall areas of the Cape. Episodic flooding in the Northern Cape in 1988 may have resulted in the unusual community in the Grootvloer temporary pool.  相似文献   

6.
Abstract

Phytogeographic and phytosociological meaning of the Sarcopoterium spinosum (L.) Spach community at S. Elia Cape (Cagliari).—Sarcopoterium spinosum (L.) Spach station at S. Elia Cape, the most western station of its distributive area, sets the question whether the accompanying vegetation must be attributed to eastern or western associations. An analysis of the species shows some residual members of the Poterium spinosum and Corydothymus capitatus Lavrentiades 1969 association, but not sufficient to recognize this coenosis, which is anyhow included in the Oleo-Ceratonion. The boundary of these coenosis with the eastern area is attributed to a N-W/S-E climate gradient, set possibly in post glacial ages.  相似文献   

7.
G. J. Broekhuysen 《Ostrich》2013,84(4):159-167
Summary

Seiler, H. W. &; Pr?s-Jones, R. P. 1989. Mate competition, mate guarding, and unusual timing of copulations in the Cape Sugarbird (Promerops cafer). Ostrich 60:159-164.

Focal observations on two breeding pairs of the Cape Sugarbird were undertaken in the Cape Peninsula, South Africa. During the presumed fertile period of the female the male was significantly less likely to become separated from his mate than during other stages of the breeding cycle. This is interpreted as mate paring, which might be triggered by the female well in advance of her actual fertile period. The presumed fertile period was closely accompanied by a sharp increase in territorial intrusions by other males. Copulations were observed only outside the presumed fertile period.  相似文献   

8.
Abstract

A new earthworm species belonging to the acanthodriline genus Rhododrilus is described from the North Island of New Zealand, elevating the generic total (excluding Australian forms) to 30 species. The new taxon forms part of the species-group with incomplete fusion of the male and prostatic terminalia. Its most closely related congener is the geographically proximate R. papaensis. Though exhibiting great heterogeneity, suggestive of polyphyly, the genus remains taxonomically convenient. It probably encompasses convergent forms, the ancestral affinities of which may never be ascertained.  相似文献   

9.
Inter-annual variations in leaf-fall phenology and leaf-litter nitrogen concentration were investigated for 13 years in a coniferous plantation of hinoki cypress trees (Chamaecyparis obtusa Endlicher) in Kochi, southern Japan. Mean annual nitrogen concentration in the leaf litter ranged from 5.97 to 7.12 g kg−1. The removal of 30 percent of the trees’ basal area in the 3rd year had little effect on leaf-litter nitrogen concentration. The nitrogen concentration in the leaf litter was not correlated with the mean temperature from March to October. The leaf-fall duration, i.e., time between 10 and 90% of the annual leaf fall, was shorter and the leaf-litter nitrogen concentration was lower when the solar radiation from March to October was higher. The results suggest that the hinoki trees shed their leaves abruptly and have lower leaf-litter nitrogen concentration when the solar radiation is higher and that effects of temperature on leaf-fall properties may not be strong in warm climate areas.  相似文献   

10.
Sugi (Cryptomeria japonica D. Don) is one of the most important evergreen coniferous plantation species in Japan. Much of the riparian forest that was originally dominated by deciduous broadleaf trees has been converted into sugi plantations. The present study investigated the seasonality of leaf-litter input and leaf dispersal to streams to assess the effects of converting riparian forest to sugi plantations. The seasonality of leaf-litter input was assessed at three streams in Nagoya University Forest. At one stream dominated by deciduous broadleaf trees, input was limited to autumn. At two streams in a sugi plantation, input was prolonged from autumn to early spring, and was dominated by sugi needles from winter to early spring. These results suggest that sugi plantations alter the seasonality of leaf-litter input from riparian forests and affect stream ecosystems. Leaf dispersal was assessed by considering the relationship between leaf dispersal distance from three forest layers to the stream and leaf-litter input into two streams. The maximum leaf dispersal distance was 26–28 m for deciduous broadleaf trees from mid-October to November and 10–12 m for sugi needles from December to April. Leaf dispersal distance depended on the tree species. Four species of deciduous broadleaf tree showed greater leaf dispersal than that of sugi. The mean weight of individual sugi needles was higher than that of the broadleaf trees’ leaves, and dispersal depended on strong winds in winter and early spring. Although the leaf dispersal distance from the understory was within 2–4 m, it could be a significant source of leaf-litter input to streams.  相似文献   

11.
Abstract

The author reports the results of the herborizations carried out on the island Piana (northeastern Sardinia) located between Cape Ceraso and Cape Coda Cavallo. The flora consists of 250 entities distributed in 154 genera, inclusive of 54 families. The author gives information regarding the mail features of the vegetal coverage, and points out the presence of two species: Limonistrum monopetalum (L.) Boiss. and Omithoga-lum arabicum L., which are extremely rare in the little islands.  相似文献   

12.
Two new pseudoscorpion species, Neobisium babinzub sp. n., and N. tarae sp. n. (Neobisiidae, Pseudoscorpiones), were collected in soil and leaf-litter on Mt. Stara Planina and Mt. Tara, Serbia, diagnosed and thoroughly illustrated. The main morphological characteristics of the two taxa clearly demonstrate their adaptation to life in soil.  相似文献   

13.
Abstract. Accumulation of nutrients in leaves of the dominating species of three ecosystems, characterizing the secondary succession from Genisto-Callunetum heathland through Leucobryo-Pinetum birch-pine woodland to mature Querco-Fagetum oak-beech forest, as well as nutrient turnover within these ecosystems was studied. The objective of the study was to establish potential variations in quantity and quality of nutrient supply to the plants with respect to succession dynamics. The results show very low leaf nutrient concentrations of all species investigated, coinciding with low nutrient availability in the soil. However, the nutrient content of leaves and leaf litter of Quercus petraea and Fagus sylvatica, which dominate the late succession stages, and in Betulapéndula are higher than in the photosynthetic organs (leaves and young shoots) of Calluna vulgaris and Pinus sylvestris. The combination of the higher nutrient content of the leaves and an increasing leaf-litter production during succession results in an increased nutrient turnover via leaf-litter fall. However, due to the high leaf biomass, the storage of nutrients in the leaf biomass is highest within the birch-pine woodland. From this, it may be assumed that the low demand and the low loss of nutrients via leaf-litter fall are favourable for Pinus at the early stages of forest succession on poor sandy soils. In contrast, Quercus and Fagus are provided with better growth conditions at the later stages of succession resulting from the accumulation of plant-available nutrients in the ecosystem by Pinus sylvestris, combined with a higher nutrient turnover as compared with the heathland.  相似文献   

14.
The new species Roella divina is described and illustrated. It belongs in R. ser. Muscosae Adamson and is closely similar to R. uncinata Cupido. R. divina is only known from mountains in the Hottentots Holland range in the Western Cape, South Africa, where it was first collected in 1916. A distribution map and conservation assessment are provided.  相似文献   

15.
The South African geophyte Lachenalia bolusii W.F.Barker is a dainty-flowered plant from semi-arid inland western parts of the Northern and Western Cape. Details of its classification, relationships, history and distribution are given, with notes on cultivation.  相似文献   

16.
《Ostrich》2013,84(3-4):195-205
A review of the taxonomic status of the critically endangered Cape Parrot Poicephalus robustus Gmelin 1788 has important implications concerning the conservation of this species and illegal trade. It is distinguishable from the Brown-necked Parrot P. fuscicollis fuscicollis Kuhl 1820 on the morphometrics of the body and bill, two mitochondrial DNA sequences and its ecology and behaviour. The Grey-headed Parrot P. f. suahelicus Reichenow 1898 is geographically and genetically isolated from the other taxa. Grey-headed Parrots and Brown-necked Parrots are more closely related to each other than either is to the Cape Parrot. Geographically, the Grey-headed Parrot is marginally parapatric with the Cape Parrot, and this account focusses on these taxa. The Cape Parrot is a dietary specialist, and its diet differs from that of the Grey-headed Parrot, which has a wider trophic niche, although both feed on the kernels of unripe fruit. Their feeding behaviour changes in response to seasonally available food and may involve long distance movements. Both species share similar breeding habits, but they breed at different seasons in different habitat types. The two taxa have distinct habitat requirements and distributions. Cape Parrots inhabit, nest and feed in Afromontane mixed Podocarpus forest above 1 000m asl in South Africa, whereas Grey-headed Parrots inhabit a wide range of lowland woodland habitats across south-central Africa. In parapatry, there is no record of hybridisation, probably because of spatial (geographical and altitudinal) and temporal segregation (different breeding seasons). On the basis of these criteria, the Cape Parrot is, and must be recognised, as an independent species.  相似文献   

17.
In a previous paper (Bull. Math. Biophysics,22, 257–262, 1960), an expression for the probability that a car jumps off a road as a function of the speed and the size of the car was derived mostly from geometric and kinematic considerations, introducing only the reaction time as a biological parameter. In subsequent papers (Bull. Math. Biophysics,29, 181–186, 187–188, 1967) a more detailed study was made of the exact shape of the tracking curve of the car which involved several biological parameters of the driver. In the present paper the results of the previous studies are combined, and a more general equation for the probability of jumping off the road is obtained. This probability, as in the earlier study, increases with the speedv, widths o and lengthl o of the car, and decreases with widths of the lane. However, this probability also depends on several parameters which characterize the psychobiological constitution of the driver. Unpublished experiments by Ehrlich, which corroborate the general conclusions, are briefly described.  相似文献   

18.
Impacts of Leaf-litter Addition on Carabids in a Conifer Plantation   总被引:2,自引:0,他引:2  
As a fine-scale, manipulative model experiment leaf litter was added in plots to increase habitat heterogeneity in a 50-year-old Norway spruce plantation, established after the clear-cutting of a native beech forest, during a 2-year period in the Hungarian Mountain Range. Pitfall trap catches of carabids from leaf-litter plots were compared with those from control plots to explore the effect of leaf-litter addition. Difference in the species composition was revealed by ordination; scores of the samples of the two plot types were significantly separated along the first MDS axis. The most numerous species (Pterostichus oblongopunctatus) was significantly more abundant in the leaf-litter plots. However, there were no significant differences for the other most frequently obtained species. Habitat generalist species were the most abundant, followed by forest generalists, then forest specialists, and there were some open habitat species. Enhanced habitat heterogeneity (leaf-litter addition) in homogeneous plantations influenced the spatial distribution and composition of carabids, through altered abiotic (lower ground temperature in the leaf-litter plots) and biotic (more prey items) factors. Differences in abundance, species richness and Shannon diversity were not significant between the control and the manipulated plots, although carabid catch was higher in the leaf-litter plots during both years. Forestry practices to increase habitat heterogeneity should be considered to enhance biodiversity in managed forests.  相似文献   

19.
Wahlenbergia cordiformis, a new species of the Lightfootia‐type is described and illustrated. It is currently only known from the farm Knolfontein, in the Swartruggens region, north east of Ceres in the Western Cape, South Africa. The closest relative of W. cordiformis is unclear, but it may be closely related to either W. tenella, W. nodosa, W. tenerrima, W. oligantha or W. neorigida. Wahlenbergia cordiformis is distinguished from them by its cordate, leaf‐like calyx lobes.  相似文献   

20.
Summary

Two incidences of mass mortality of fish were recorded in two saline waterbodies (Swartvlei estuary and Rondevlei) in the Wilderness National Park. Species affected were the Knysna seahorse (Hippocampus capensis) and longsnout pipefish (Syngnathus acus) in the Swartvlei estuary, and Cape stumpnose (Rhabdosargus holubi) and white steenbras (Lithognathus lithognathus) in Rondevlei. Comparison of water quality parameters during fish mortalities to past ranges and reported species tolerances indicated that the probable causes for the mortalities were high water temperature in the Swartvlei estuary, and low dissolved oxygen concentration in Rondevlei.  相似文献   

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