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  • 1. The worldwide trade in aquarium fish is a multi‐billion dollar industry. One of the most popular and expensive species traded is the Asian arowana Scleropages formosus. As a result of over‐harvesting for the aquarium fish trade, S. formosus is now endangered and commercial international trade in the species is prohibited under CITES. Despite this, very little is known about S. formosus in the wild.
  • 2. Interviews were conducted with 62 local villagers at four sites in Koh Kong province, south‐west Cambodia, to obtain information on the reproduction, historical and current harvest and trade, and population trends of S. formosus.
  • 3. The spawning season of S. formosus in Cambodia begins towards the end of the dry season (March–April) and is approximately 3 months in duration. Each male mouth‐broods an average of 30 juveniles. Harvesters target S. formosus fry and juveniles, and typically kill or frighten brooding males into releasing their offspring in order to harvest them.
  • 4. The prices obtained by harvesters for S. formosus has been increasing since collection began, and currently averages $US11–13 per juvenile. After collection, fish are transported through a series of larger towns, most ultimately bound for Thailand. The current number of S. formosus harvested from the wild in Cambodia is almost certainly highly unsustainable, with all respondents indicating that local S. formosus population abundance had declined dramatically in recent years. It is also likely that a number of populations have already become locally extinct.
  • 5. Strengthening legislation to protect the species within Cambodia, increasing enforcement of cross‐border trade, and an investigation into alternative low‐impact income generation opportunities for local communities is vital. There is also an urgent need to gather detailed information on the distribution, population abundance and threats facing S. formosus in Cambodia, and in other countries throughout its range.
Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
2.
香港有机高尔夫球场的草坪管理研究实施   总被引:4,自引:0,他引:4  
OGC启德高尔夫球场为香港首个有机高尔夫球场,本文提出了有机高尔夫球场的管理标准,并以有机农业方式作出高尔夫球场草坪的水肥等栽培管理及病虫草害的综合生态防治方法,为今后有机高尔夫球场的发展提供参考。  相似文献   
3.
The objective of the study was to evaluate effects of Quillaja saponaria (QS) with or without Yucca schidigera extract (YS) on in vitro ruminal fermentation and methanogenesis. The culture media consisted of 400 mL of strained rumen fluid collected from two non‐lactating Holstein cows and 400 mL of artificial saliva. The culture media was anaerobically incubated with 10 g of a mixture of concentrate and oat hay (1:1, w/w) at 39°C for 24 h. The treatments were arranged as 2 × 3 factorial design experiment consisting of three levels of QS (0, 2 or 4 mL/L) and two levels of YS (0 or 2 mL/L). Treatment interactions between QS and YS were observed for pH and ammonia N concentration. CH4 production was not modified by addition of QS but decreased (P < 0.05) when added with YS. Addition of QS with YS increased (P < 0.05) propionate concentrations. Protozoa numbers were decreased (P < 0.05) by QS addition alone or with YS. Results show that QS and YS exhibited strong antiprotozoal effects and combinations of both plant extracts may have potential as safe manipulators of ruminal fermentation.  相似文献   
4.
A 4 × 6 Youden square design was used to study manipulating effect of Yucca schidigera with or without nisin on rumen fermentation characteristics and microbial protein synthesis in sheep fed silage‐ and hay‐based diets. Four ruminally canulated wethers were given isonitrogenous diets of timothy silage and concentrate (85:15) (S), and timothy hay and concentrate (60:40) (H), on DM basis. The six experimental diets were: (i) S; (ii) S + 240 ppm of Yucca schidigera (SY); (iii) S + 240 ppm of Yucca schidigera + 6 mg/kg bodyweight (BW)0.75 of nisin (SYN); (iv) H; (v) H + 240 ppm of Yucca schidigera (HY); and (vi) H + 240 ppm of Yucca schidigera + 6 mg/kg BW0.75 of nisin (HYN). Rumen pH was higher (P < 0.01) in sheep fed SYN diet than those fed S diet. Concentration of ammonia‐N (NH3‐N) was significantly lower (P < 0.05) in sheep fed SY, SYN, HY, HYN than those of S and H. Total volatile fatty acids concentration was significantly lower (P < 0.05) in HYN than in H diet and tended to be higher in sheep fed H diets than those fed S diets. There was a significantly higher (P < 0.01) efficiency of microbial nitrogen synthesis in the rumen of sheep fed on HY diet than those fed on H diet.  相似文献   
5.
The effects of variety and growth location on grain composition and starch structures were investigated using three rice (Oryza sativa L.) cultivars (Phka Romduol, Sen Pidao and IR66) with different amylose contents. All the three cultivars were planted in three different agro-climatic zones (Phnom Penh, Coastal and Plateau) of Cambodia. The protein content of polished grains increased when rice was planted at a location with higher average temperature, but their lipid content decreased. The amylose content and degree of branching were not greatly affected by the minor temperature differences among the growing locations. Starch fine structures characterized by the chain-length distribution were significantly different among the cultivars, but not significantly among different locations. The results suggested that protein and lipid biosyntheses were more sensitive to the environmental temperature than that of starch in rice grains.  相似文献   
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