Kota Kinabalu, Malaysia
Kota Kinabalu, Malaysia

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Lee S.,University of Auckland | Hartstein N.D.,No. 28 | Jeffs A.,University of Auckland
Aquaculture International | Year: 2015

Spiny lobster aquaculture in sea-cages produces both particulate (faeces and waste feed) and soluble wastes [dissolved inorganic nitrogen (DIN)] that have the potential to degrade the environment. To begin to understand the environmental impacts of tropical spiny lobster aquaculture, the waste products of these lobsters were quantified, including the settling velocity of faecal material and DIN output from lobsters of a range of sizes and fed two dietary treatments (seafood and artificial diet), as well as determining the nitrogen leaching from faeces and diets for lobsters. The mean faeces settling velocity of lobsters fed with seafood was significantly higher than those from lobsters fed with artificial diet (0.30 ± 0.01 and 0.22 ± 0.01 cm s−1, respectively, mean ± SE), but the settling velocity of faeces did not differ among the lobsters of different sizes for each diet. The settling velocity of faecal material showed a positive relationship with faeces weight, volume and density but not length. Both carbon and nitrogen content in faeces showed no significant differences between the two diets. Feeding activity doubled the DIN output from lobsters consistently for both dietary treatments compared with unfed lobsters. Nutrient leaching from samples of faeces and diet was highly variable and did not differ among lobsters of different sizes or between the two dietary treatments. Overall, while faecal material, waste feed, as well as DIN excretion by lobsters in aquaculture operations could potentially negatively impact the environment, their faeces settling velocity and DIN output is markedly lower than fin-fish. Thus, the environmental impact from lobster aquaculture is unlikely to be as intensive as for fin-fish aquaculture. © 2015, Springer International Publishing Switzerland.


Lee S.,University of Auckland | Hartstein N.D.,No. 28 | Jeffs A.,University of Auckland
ICES Journal of Marine Science | Year: 2015

The tropical spiny lobster, Panulirus ornatus, is farmed in floating sea cages situated in shallow coastal waters in many parts of the Asia-Pacific region. Despite the rapid expansion of this aquaculture activity, very little is known about its environmental impacts. This study combines computer modelling with previous laboratory measures to provide information on benthic carbon deposition and the production of dissolved inorganic nitrogen (DIN) from hypothetical sea cage aquaculture of spiny lobsters. Modelling scenarios were run with two different lobster aquaculture stocking densities (3 and 5 kg m-3) and various feed conversion ratios (FCRs) using natural seafood or artificial lobster diet (FCR 1.28-28). Simulations from the model showed that cumulative benthic carbon deposition varied from 0.1 to over 0.8 kg C m-2 year-1, while the mean DIN levels around sea cages ranged from 5.6 up to 25 μg N l-1 and the maximum DIN levels ranged from 10.8 to 165 μg N l-1. The results showed that feeding lobsters with seafood resulted in a markedly higher benthic carbon loading and release of DIN when compared with artificial lobster feed. Therefore, the elimination of the use of trash fish would greatly reduce the environmental impacts of spiny lobster aquaculture. Overall, the effects from spiny lobster aquaculture were spatially localized with the highest concentrations of carbon deposition and DIN directly beneath the sea cages. Therefore, it seems unlikely that spiny lobster aquaculture in sea cages will cause adverse environmental effects unless the lobsters are heavily stocked and supplied with poor quality feed. © 2014 International Council for the Exploration of the Sea 2014. All rights reserved. For Permissions, please email: journals.permissions@oup.com.


Wang H.,No. 28 | Bernell D.,Oregon State University
Journal of Environment and Development | Year: 2013

In 2008, China launched the Green Securities Policy to increase sustainability practices among companies listed on Chinese stock markets. An integral component of the policy is the environmental disclosure regulation, which directs publicly traded Chinese companies in 14 highly polluting industries to report required environmental information. This research explores the Green Securities Policy in two ways. First, it determines the compliance level with environmental disclosure requirements from 2008 to 2010 by companies covered under the Green Securities Policy. The findings indicate that about 60% of listed companies report the required environmental information at some level. Second, the research examines the dynamics underlying environmental disclosure by Chinese listed companies through the lens of ecological modernization theory. While China's ecological modernization has created an increasingly favorable environment for environmental disclosure regulation, the research highlights problems that have impeded the progress of environmental disclosure by listed companies. © The Author(s) 2013.


Lee S.,University of Auckland | Hartstein N.D.,No. 28 | Jeffs A.,University of Auckland
Environmental Science and Pollution Research | Year: 2015

Although the aquaculture of spiny lobsters has been expanding since the 1970s, very little is known about the potential environmental impacts on water quality of this activity. This study quantified the production of dissolved inorganic nitrogen (DIN) from Australasian red spiny lobsters, Jasus edwardsii, in the laboratory, and these data were then used in a numerical model to predict the dispersal pattern of DIN from a hypothetical commercial spiny lobster farm for a coastal site where such a farm would typically be located. Modelling scenarios were set up with combinations of two different stocking densities (3 and 5 kg m−3), two different diets (mussels and moist artificial diet) and three different feed conversion ratios (FCR = 3, 5 and 28). DIN excretion rate from unfed lobsters in the laboratory on average was 1.10 ± 0.12 μg N g−1 h−1 while feeding lobsters on mussels and artificial diet increased DIN excretion significantly by around eightfold and twofold, respectively. Ammonia was consistently the dominant contributor to measured DIN output from lobsters. Modelling results indicated that the mean elevated DIN from a hypothetical farm where the lobsters were fed with mussels ranged from 7 up to 20 μg N L−1 with increasing stocking density and FCR and was 30–150 % higher than the mean elevated DIN resulting from lobsters fed with artificial diet. Overall, the results indicated that DIN output from the hypothetical spiny lobster sea-cage farming is unlikely to be problematic using the FCR, stocking density, and the number of cages modelled at the coastal site in this study. Furthermore, feeding lobsters with artificial diet can help maintain a lower DIN output than seafood, such as mussels or trash fish. © 2015, Springer-Verlag Berlin Heidelberg.


Wang G.,No. 28 | Song Q.,No. 28 | Zhang X.,No. 28 | Zhang K.,No. 28
ACM Transactions on Knowledge Discovery from Data | Year: 2014

As more and more classification algorithms continue to be developed, recommending appropriate algorithms to a given classification problem is increasingly important. This article first distinguishes the algorithm recommendationmethods by two dimensions: (1)meta-features,which are a set ofmeasures used to characterize the learning problems, and (2) meta-target, which represents the relative performance of the classification algorithms on the learning problem. In contrast to the existing algorithm recommendation methods whose meta-target is usually in the form of either the ranking of candidate algorithms or a single algorithm, this article proposes a new and natural multilabel form to describe the meta-target. This is due to the fact that there would be multiple algorithms being appropriate for a given problem in practice. Furthermore, a novel multilabel learning-based generic algorithm recommendation method is proposed, which views the algorithm recommendation as a multilabel learning problem and solves the problem by the mature multilabel learning algorithms. To evaluate the proposed multilabel learning-based recommendation method, extensive experiments with 13 well-known classification algorithms, two kinds of meta-targets such as algorithm ranking and single algorithm, and five different kinds of meta-features are conducted on 1,090 benchmark learning problems. The results show the effectiveness of our proposed multilabel learning-based recommendation method. © 2014 ACM.

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