Seasonal effects on litterfall in a Hong Kong mixed forest

1985 ◽  
Vol 1 (1) ◽  
pp. 55-64 ◽  
Author(s):  
Paul K. S. Lam ◽  
David Dudgeon
Keyword(s):  
Hong Kong ◽  
Climatic Factors ◽  
Mixed Forest ◽  
Seasonal Distribution ◽  
Seasonal Effects ◽  
Litter Production ◽  
Leaf Fall ◽  
Organic Debris ◽  
Woody Litter ◽  
Nutrient Economy

ABSTRACTAn investigation of seasonal rates of litter production in a mixed forest, Hong Kong Island, was undertaken from October 1982 to January 1984. Total annual litterfall amounted to 1218.96 g m−2 yr−1, comprising 68.6% leaves, 18.9% woody material, and 12.5% fruits, seeds and insect frass. 398.70 g m−2 of litter was recorded immediately after a severe typhoon (9 September 1983). Rates of leaf-fall and organic debris production were correlated with prevailing temperature and rainfall. Leaf-fall peaked in January 1983, March to July 1983, and in September 1983 after the typhoon, while large amounts of insect faeces were collected in May and June. Woody litter production rates were correlated with temperature and rainfall recorded in previous months. Woody litterfall exhibited no obvious periodicity but was slightly increased during March and April. The seasonal distribution of litterfall is discussed in relation to climatic factors and habitat nutrient economy.

scholarly journals Seasonal Effects on Starch Contents Evaluated in Cassava Roots

2017 ◽  
Vol 9 (10) ◽  
pp. 244
Author(s):  
Genilso Gomes de Proença ◽  
Carla Adriana Pizarro Schmidt ◽  
José Airton Azevedo dos Santos
Keyword(s):  
Climatic Factors ◽  
Starch Content ◽  
Raw Material ◽  
Seasonal Effects ◽  
Winter Period ◽  
Genetic Characteristics ◽  
Wide Range ◽  
Product Delivery ◽  
Root Starch

Starches have a wide range of uses and their consumption has increased over the years, resulting in a growth in the agro-industries that produce them. Cassava is a very important plant for agri-business and one of the main products obtained from its roots is starch. Although cassava can be harvested throughout the year, its quality varies greatly through the seasons; this is because it is influenced by soil and climatic factors, as well as the genetic characteristics of the species. These influences result in seasonal oscillations in root classification based on the starch content available at the time of product delivery. Faced with this problem, the objective of this study was the collection and evaluation of documentary data for 3 years of product quality samples. This was done in order to observe the situation and propose tools that can minimize problems resulting from the quality of raw material received by starch producers throughout the year. It was observed that in the winter period there was an increase in root starch content, despite the differences between the months not being statistically significantly, they are financially representative of this agro-industry sector. At the end of the study, a proposal for a methodology for calculating payment per gram of starch is presented in order to minimize the problem.

scholarly journals Circulating Influenza Virus, Climatic Factors, and Acute Myocardial Infarction: A Time Series Study in England and Wales and Hong Kong

2011 ◽  
Vol 203 (12) ◽  
pp. 1710-1718 ◽  
Author(s):  
Charlotte Warren-Gash ◽  
Krishnan Bhaskaran ◽  
Andrew Hayward ◽  
Gabriel M. Leung ◽  
Su-Vui Lo ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Acute Myocardial Infarction ◽  
Time Series ◽  
Influenza Virus ◽  
Hong Kong ◽  
Climatic Factors ◽  
England And Wales ◽  
Time Series Study ◽  
Series Study

Leaf survival of woody plants in deciduous broad-leaved forests. 1. Tall trees

1983 ◽  
Vol 61 (8) ◽  
pp. 2133-2139 ◽  
Author(s):  
Kihachiro Kikuzawa
Keyword(s):  
Short Duration ◽  
Mixed Forest ◽  
Evolutionary Trend ◽  
Leaf Fall ◽  
Emergence Pattern ◽  
Leaf Emergence ◽  
Tall Tree ◽  
Open Land ◽  
Winter Buds

Seasonal changes in mean numbers of leaves per shoot were shown for 41 tall-tree species in deciduous broad-leaved forests in Hokkaido, northern Japan. Three types of leaf-emergence pattern were recognized; namely (1) succeeding type, (2) intermediate type, and (3) flush type. The two species showing the succeeding type emergence pattern have homonomous winter buds characterized by one-lamina and two-stipules sets. The species of intermediate- or flush-type emergence pattern usually have heteronomous winter buds with several bud scales. A negative correlation was found between leaf-emergence duration and number of bud scales. Species having a long leaf-emergence duration were open land or gap invaders. Among them, those having long leaf-fall duration were found in riverside forests. On the other hand, species showing flush-type leaf emergence with short duration and almost simultaneous leaf fall with also short duration were mainly found in mixed-forest stands. The longevities of leaves at the basal part of the shoot were short in the species whose bud scales have not entirely differentiated from foliage leaves. The main evolutionary trend in the shoots was suggested to be from homonomous to heteronomous structure and towards the clear distinction between foliage leaves and bud scales.

scholarly journals Pollination in a degraded tropical landscape: a Hong Kong case study

2001 ◽  
Vol 17 (1) ◽  
pp. 155-161 ◽  
Author(s):  
RICHARD T. CORLETT
Keyword(s):  
Hong Kong ◽  
Plant Species ◽  
Mixed Forest ◽  
Pollination Biology ◽  
Individual Plant ◽  
Secondary Forests ◽  
Yakushima Island ◽  
Northern Margin ◽  
Broad Leaved Forest ◽  
The Tropics

Although the pollination biology of many individual plant species has been investigated in the Oriental region, there have been very few community-level studies. The two most comprehensive of these were in the primary mixed dipterocarp forest of Lambir Hills National Park, Sarawak (4°20′N: Momose et al. 1998, Sakai et al. 1999) and in the warm temperate evergreen broad-leaved forest and cool temperate mixed forest on Yakushima Island (30°N: Yumoto 1987, 1988). Hong Kong (22°17′N) lies midway between these sites, at the northern margin of the tropics, where winter temperatures fall below 10 °C at sea-level for a few days every year and there are occasional frosts above 400 m (Dudgeon & Corlett 1994). Latitudinal effects, however, are compounded in comparisons with other well-studied East Asian sites, by centuries of massive human impact, leaving a degraded landscape of steep, eroded hillsides, covered in fire-maintained grassland, secondary shrublands and, locally, secondary forests (Zhuang & Corlett 1997). This history has left a relatively impoverished fauna but a surprisingly diverse flora, including 400 native tree species (Corlett & Turner 1997). In these circumstances, failures of pollination and dispersal mutualisms might be expected to accelerate the loss of plant species from the landscape (Bond 1994, Kearns & Inouye 1997). Previous studies have shown that most woody vegetation in Hong Kong is dominated by species whose seeds can be dispersed by the commonest avian frugivores, the light-vented and red-whiskered bulbuls (Pycnonotus sinensis (Gmelin) and P. jocosus (Linn.)) and the Japanese white-eye (Zosterops japonicus Swinhoe) (Corlett 1996, 1998), but there is no equivalent information available on pollination biology.

Litterfall and productivity in a tropical rain forest, Southern Baakundu Forest Reserve, Cameroon

1988 ◽  
Vol 4 (1) ◽  
pp. 25-37 ◽  
Author(s):  
Nicholas C. Songwe ◽  
F. E. Fasehun ◽  
D. U. U. Okali
Keyword(s):  
Relative Humidity ◽  
Linear Regression ◽  
Rain Forest ◽  
Climatic Factors ◽  
Leaf Fall ◽  
Leaf Production ◽  
Forest Reserve ◽  
Weight Losses ◽  
Time Of Year ◽  
Canopy Species

ABSTRACTLitterfall was measured monthly in ten 1 m2 traps in each of two 0.25 ha plots in the rain forest of Southern Bakundu Forest Reserve, Cameroon for 18 months from 1 July 1982 to 31 December 1983. Particular emphasis was placed on measuring species contributions and in relating litterfall to climatic factors; the litterfall data were also used in estimating leaf production. Annual litterfall ranged between 12.9 and 14.1 t ha−1 and was partitioned to leaves (61–66%), branches (23–38%), fruits and flowers (8–12%) and ephiphytes (0.8%). Emergents and top canopy species like Desbordesia glaucescens (evergreen) and Ceiba pentandra (deciduous) contributed more litter than the numerically dominant lower storey species like Cola lepidota and Diospyros spp. Litter fell throughout the year but was greatest during the dry season (November to March); litterfall was thus strongly negatively correlated with environmental moisture variables and could be predicted from its linear regression on time of year, throughfall and relative humidity. By correcting the leaf fall data for leaf weight losses due to grazing and re-translocation, leaf production rates of 10.2 to 11.2 t ha−1 yr−1 were estimated for the forest.

scholarly journals Climatic factors associated with hospitalizations for rotavirus diarrhoea in children under 5 years of age

2007 ◽  
Vol 136 (1) ◽  
pp. 56-64 ◽  
Author(s):  
R. M. D'SOUZA ◽  
G. HALL ◽  
N. G. BECKER
Keyword(s):  
Hospital Admissions ◽  
Climatic Factors ◽  
Seasonal Effects ◽  
Effect Of Temperature ◽  
Factors Associated ◽  
Average Temperature ◽  
Temperature And Humidity ◽  
Higher Temperature ◽  
Log Linear ◽  
Children Under 5

SUMMARYThis study compares the seasonality of rotavirus diarrhoeal hospital admissions and its relationship to climatic factors across three Australian cities. Weekly admission of rotavirus diarrhoea (1993–2003) in children aged <5 years and weekly average temperature and relative humidity for each city were modelled using a log-linear model with a cubic trend and season. Interactions were included to test for differences in the effect of temperature and humidity between seasons and between cities. Admissions of rotavirus diarrhoea peaked in winter and spring and were lowest in summer. Higher temperature and humidity in the previous week were associated with a decrease in rotavirus diarrhoeal admissions in three cities. The effects of both temperature and humidity on rotavirus admissions in Brisbane differed across seasons. Strategies to combat outbreaks of rotavirus diarrhoea should take climatic factors and seasonal effects into consideration to plan for the excess seasonal hospital admissions.

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