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91.
Of the few studies that have examined in situ coral growth responses to recent climate change, none have done so in equatorial waters subject to relatively high sea temperatures (annual mean >27°C). This study compared the growth rate of Porites lutea from eight sites at Phuket, South Thailand between two time periods (December 1984–November 1986 and December 2003–November 2005). There was a significant decrease in coral calcification (23.5%) and linear extension rates (19.4–23.4%) between the two sampling periods at a number of sites, while skeletal bulk density remained unchanged. Over the last 46 years, sea temperatures (SST) in the area have risen at a rate of 0.161°C per decade (current seasonal temperature range 28–30°C) and regression analysis of coral growth data is consistent with a link between rising temperature and reduced linear extension in the order of 46–56% for every 1°C rise in SST. The apparent sensitivity of linear extension in P. lutea to increased SST suggests that corals in this part of the Andaman Sea may already be subjected to temperatures beyond their thermal optimum for skeletal growth. Communicated by Environment Editor Prof. Rob van Woesik  相似文献   
92.
The toxic benthic dinoflagellate genus Ostreopsis has been connected to the production of palytoxin and its analogs in many tropical and temperate areas. Although the type species, O. siamensis, was originally described from the Gulf of Thailand in 1901, little is known about the species composition and distribution of the genus Ostreopsis in Thailand. In this study, a total of 64 Ostreopsis strains isolated from the Andaman Sea as well as the Gulf of Thailand were investigated by analyzing the nucleotide sequences of the LSU rDNA D1/D2, D8/D10 and ITS-5.8S rDNA regions. Phylogenetic analyses (BI and ML) resulted in some of the strains being assigned to previously described clades, O. cf. ovata and Ostreopsis sp. 6, and revealed the existence of a novel clade named Ostreopsis sp. 7, which exhibited large genetic distances from the other clades. Among O. cf. ovata, several strains from Thailand were formed into a new subclade, the Thailand subclade, whereas a few strains belonged to the South China Sea subclade. Morphometric characteristics such as the cell sizes of the two O. cf. ovata subclades and those of Ostreopsis sp. 7 were not significantly different from each other (p > 0.05). Their characteristics were similar but slightly different from those of O. ovata and were significantly different from those of Ostreopsis sp. 6 (p < 0.05). Toxicities of Ostreopsis from Thailand were evaluated using mouse bioassay. Strains of Ostreopsis sp. 6 and Ostreopsis sp. 7 tested were highly toxic, while the two subclades of O. cf. ovata strains seemed to be nontoxic. This study suggests that toxic Ostreopsis sp. 7 is distributed in the Andaman Sea, whereas the two subclades of O. cf. ovata and toxic Ostreopsis sp. 6 are distributed in the Gulf of Thailand.  相似文献   
93.
A new species,Thomsonia sumawongii Bogner, is described from Thailand. Relationships toTh. napalensis and betweenThomsonia, Pseudodracontium andAmorphophallus are discussed.Allopythion hookeri Schott has to be eliminated as dubious.
  相似文献   
94.
Wild bear populations in Southeast Asia are threatened with extinction, but the ecology and distribution of the 2 species occurring in the region's protected areas is poorly known, so there is little scientific basis underlying conservation strategies. We used bear signs, primarily claw marks on climbed trees, to study habitat selection and distribution of Asiatic black bear (Ursus thibetanus) and sun bear (Helarctos malayanus) across Khao Yai National Park, Thailand from March to December 2008. We found black bear claw marks in 24 of 30 random sample blocks (80%), indicating that this species was widely distributed across Khao Yai. Sun bear signs were much scarcer: their claw marks occurred in 11 blocks (37%); data were too sparse for sun bear so we limited our focus to Asiatic black bear. Using logistic regression, we found that fruit abundance best explained variation in presence of black bear, whereas human disturbance, distance to park edge, elevation, and ground cover had little influence. Fruits appear to be a key resource for Asiatic black bears, and factors affecting fruit abundance or shifts in seasonality (e.g., climate change) will impact bear populations. Knowledge of this relationship will allow managers to be more proactive in managing bears. We recommend using sign surveys for monitoring changes in black bear occupancy as they are inexpensive, efficient, and can be conducted by trained park rangers. © 2011 The Wildlife Society.  相似文献   
95.
96.
Goal and Scope The goal of this study is to explore the potentials and limitations of using LCA as the basis for setting ecolabelling criteria in developing countries. The practicality of using LCA for this purpose, as required by ISO 14020, has been criticised as lacking in transparency and scientific rigour. Furthermore, ecolabelling is not widespread in developing countries. The application of LCA has therefore been illustrated by using the specific case of shrimp aquaculture in Thailand, as a basis for ecolabelling criteria for a typical product intended for export from a developing country. Method For the LCA case study, the functional unit is the standard consumer-package size, containing 1.8 kg of frozen shrimp produced by conventional intensive aquaculture in Thailand, subject to an appropriate environmental management system. The impact assessment method used in this study is CML 2 Baseline 2000. Results According to the results from the LCA study, farming appears to be the key life cycle stage generating the most significant environmental impacts: abiotic depletion and global warming, which arise mainly from the use of energy; and eutrophication caused by wastewater discharged from the shrimp ponds. It is possible to cover these impacts by quantitative ecolabelling criteria. Other important impacts could not be quantified by the LCA: depletion of wild shrimp broodstock, impacts of trawling on marine biodiversity and the choice of suitable farm sites. These impacts, which are also related to the farming stage, must be covered by 'hurdle criteria'. Conclusions and recommendations. For the present case, LCA provides a basis for quantifying a number of important ecolabelling criteria related to the use of abiotic resources and to emissions. Other important issues, connected with the use of biotic natural resources and land, are not quantifiable by current LCA methodology, but were also revealed and clarified by using an LCA framework for the analysis. Thus, focussing the assessment on life cycle considerations, as required by ISO 14024, was effective in identifying all key environmental issues. In the light of this case study, main limitations and barriers associated with the application of LCA to setting ecolabelling criteria particularly in developing countries are discussed, including recommendations on how to overcome them.  相似文献   
97.
《Journal of Asia》2020,23(2):578-584
The Oriental leafhopper genus Cassianeura Ramakrishnan & Menon is reviewed with two new species records from Thailand: C. cassiae (Ahmed, 1970) and C. bimaculata Dworakowska, 1984. The three species of the genus are redescribed and illustrated including details of the female ovipositor for the first time. A key to distinguish the three species of the genus is provided.  相似文献   
98.
《Annales de Paléontologie》2019,105(3):245-253
Skull and mandibular elements of a tomistomine crocodilian are described from the late Eocene to early Oligocene lignite seams of Krabi, peninsular Thailand. The Thai tomistomine is a longirostrine form characterized by a rostrum/skull ratio of about 0.6; a mandibular symphysis reaching the level of the eleventh alveolus; a deep participation of the splenial in the symphysis to the level of the ninth alveolus; an enlarged fifth maxillary alveolus; long nasals reaching the premaxillae at the level of the fifth maxillary alveolus but not contributing to the external nares; undivided posterior processes of premaxillae; a short prefrontal, excluded by a longer lacrimal from the posteromedial margin of maxillae; vomers visible on the palate. A phylogenetic analysis recovers the Thai specimen among derived tomistomines, on the stem lineage of the extant Tomistoma schlegelii, as a close ally of Maomingosuchus petrolica, a late Eocene tomistomine from southern China. The present recognition of Maomingosuchus sp. in late Eocene Thai deposits expands the distribution of Eocene tomistomines from southern China to the tropics. The origin of Tomistominae in Asia is briefly discussed.  相似文献   
99.
Two species of fish-eating bird namely, Amaurornis phoenicurus and Ardeola bacchus were fed with infective larvae of Capillaria philippinensis in Gambusia holbrookii. Intestinal capillariasis was able to establish in all three A. phoenicurus and one of three A. bacchus. Prepatent period in A. phoenicurus ranged from 22 to 30 days, whereas in A. bacchus it was 16 days after infection. Auto-infection was observed in all susceptible birds and the protective immunity had developed in one of A. phoenicurus used.  相似文献   
100.
Free-grazing ducks play a major role in the rural economy of Eastern Asia in the form of egg and meat production. In Thailand, the geographical location, tropical climate conditions and wetland areas of the country are suitable for their husbandry. These environmental factors also favor growth, multiplication, development, survival, and spread of duck parasites. In this study, a total of 90 free-grazing ducks from northern, central, and northeastern regions of Thailand were examined for intestinal helminth parasites, with special emphasis on zoonotic echinostomes. Of these, 51 (56.7%) were infected by one or more species of zoonotic echinostomes, Echinostoma revolutum, Echinoparyphium recurvatum, and Hypoderaeum conoideum. Echinostomes found were identified using morphological criteria when possible. ITS2 sequences were used to identify juvenile and incomplete worms. The prevalence of infection was relatively high in each region, namely, north, central, and northeast region was 63.2%, 54.5%, and 55.3%, respectively. The intensity of infection ranged up to 49 worms/infected duck. Free-grazing ducks clearly play an important role in the life cycle maintenance, spread, and transmission of these medically important echinostomes in Thailand.  相似文献   
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