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61.
  1. The catchments of the Great Barrier Reef (GBR) in Australia include more than one million ha of wetlands, which help to sustain the health and resilience of the reef.
  2. This article reviews the status, values, and threats of wetlands in the GBR catchments, as well as the management, protection, and challenges and opportunities for their restoration and rehabilitation.
  3. At present, wetlands in the GBR catchments have low rates of area loss and are generally well protected; however, they face major management challenges owing to the intensive land use of the catchments, especially for grazing, agriculture, horticulture, and mining. Major threats to these wetlands include water pollution, invasive species, changes in hydrology, and increasing temperature and salinity resulting from climate change.
  4. In recent years wetlands have been considered primarily for their role in improving water quality to ameliorate contaminated terrestrial run‐off to the GBR, with little attention given to their intrinsic value and other ecosystem services.
  5. Financial opportunities for wetland restoration in addition to government‐funded schemes include water pollution offsets, payment for ecosystem services, and nitrogen markets.
  6. Wetlands need to be protected, managed, and restored for the ecosystem services that they provide to the GBR, but also for their intrinsic value as significant features of coastal landscapes.
  相似文献   
62.
Parental condition‐dependent offspring fitness is a well‐discussed issue in animal breeding research, while offspring environment and its interaction with parental condition are currently another very interesting topic to investigate the plasticity of phenotypic traits across an environmental gradient. The present study was, therefore, conducted following a half‐sib breeding design to test the effects of (a) paternal body size, (b) offspring feeding strategy (everyday and every other day) and (c) their interactions on fitness‐related traits (e.g., survival, total length and body area) of offspring of a commercially important aquaculture species, the Indian major carp (Labeo rohita). The analysis revealed that paternal body size had significant effects on offspring survival rate and total length, while no significant influence was found in body area. The study also showed that the offspring feeding strategy significantly affected all offspring traits. Interestingly, the study unveiled the significant interactive effects of paternal condition and offspring feeding for offspring survival rate and total length. These findings suggest that paternal size, offspring rearing environment and their interactions can influence offspring fitness‐related traits which are very essential information for the sustainable production of good quality larvae under variable dietary conditions.  相似文献   
63.
Light and shelter are very important ecological factors that can affect many traits of fish. Therefore, a study was conducted to explore the effect of light and shelter on some phenotypic traits of stinging catfish (Heteropneustes fossilis Bloch, 1794). During experiment, equal‐sized juveniles (mean ± SE: 9.04 ± 0.09 cm) were collected and reared in aquariums dividing into four treatment groups, such as T1 (0L:24D without pipe), T2 (0L:24D with pipe), T3 (12L:12D without pipe) and T4 (12L:12D with pipe). Each treatment had 36 fish, which were randomly distributed into three replications. The fish were kept up to 120 days, and then, the growth performance and skin colour were analysed. The results showed that both lighting and shelter conditions as well as their interactions had significant effects on some traits expression. The analyses revealed that lighting condition significantly influenced body area, head width and skin coloration, while shelter condition significantly affected total and standard length, body area, and their interaction showed significant effects on body area, head width and anal fin length. Thus, this study indicates that stinging catfish show better growth performance and colour patterns especially in dark and sheltered conditions which could be recommended for the successive production of this highly priced fish species.  相似文献   
64.
We investigated the effects of two commercial diatomaceous earth based insecticides (DE), Protect-It® and SilicoSec®, the nano-structured silica product AL06, developed by the section for Urban Plant Ecophysiology at Humboldt University Berlin, and the monoterpenoids, eugenol, and cinnamaldehyde on two stored product pests, Callosobruchus maculatus and Sitophilus oryzae. Protect-It® was more effective than SilicoSec® against C. maculatus while the reverse was true for S. oryzae. Generally C. maculatus was more sensitive towards DE and silica treatment than S. oryzae. Mortality rate of both pest species increased when DE’s were applied to food commodities previously treated with a monoterpenoid. In admixture experiments, the toxicity of SilicoSec® + cinnamaldehyde (LD50 = 42.73 ppm), SilicoSec® + eugenol (LD50 = 24.30 ppm), and Protect-It® + eugenol (LD50 = 2.60 ppm) was increased over DE alone against S. oryzae. Both substances showed a synergistic effect considering their co-toxicity coefficient relative to the LD50-value. In contrast, we could not find any synergistic effects in experiments with C. maculatus. Here only Protect-It® + cinnamaldehyde (LD50 = 20.84 ppm) showed an additive effect while all other combinations of monoterpenoid and DE indicated antagonistic effects. In addition to contact insecticidal effects both monoterpenoids showed a strong fumigant action. The presented results indicate that the natural product DE has great potential to replace synthetic pesticides commonly used in stored product pest management. Efficacy of DE can be improved by adding certain monoterpenoids against certain insect pests.  相似文献   
65.
Chowdhury R  Hasan CM  Rashid MA 《Fitoterapia》2003,74(1-2):155-158
The extracts of two Bangladeshi medicinal plants, Toona ciliata (stem bark) and Amoora rohituka (stem bark), along with siderin, a major coumarin from T. ciliata, exhibited significant in vitro antibacterial activity. The extracts also demonstrated mild antifungal effect.  相似文献   
66.
This study was carried out to investigate the prevalence and economic losses due to in cattle of hypodermosis between May 2008 and April 2009 in Afyonkarahisar province of Turkey. A total of 6,598 cattle—3,498 in pasture and 3,100 in slaughterhouse—were examined for hypodermosis. One hundred ninety-five out of 6,598 cattle (2.96%) were found positive. Concerning this infestation rate, the prevalence of hypodermosis in field was 5.3%, whereas the prevalence was 0.3% in slaughter house. Hypoderma bovis and Hypoderma lineatum were recorded in slaughter house. First-stage Hypoderma spp. larvae weren’t found in cattle organs in slaughterhouse. The annual economic loss on skins is estimated to be about 18,288 TL (currency exchange rate is 1 USD:1.499 TL).  相似文献   
67.
Veterinary Research Communications - The pet cat’s population and the number of viruses that infect them are increasing worldwide. Recently, feline chaphamaparvovirus (FeChPV, also called...  相似文献   
68.
The functional properties of proteins from Tarom and Shiroodi cultivars were determined and compared with technological aspects of food and nutraceutical applications. Shiroodi has higher protein content than Tarom, and the yields of protein obtained were 72.88 and 66.36%, respectively. Nitrogen solubilities of rice bran protein of Tarom were more than Shiroodi at all pH levels. In addition, higher solubility was found in acidic or alkaline conditions. Although the rice bran proteins had lower emulsifying properties than bovine serum albumin, they had similar foaming properties in comparison with egg white. Tarom isolates had a significantly higher solubility, emulsifying property, and foaming stability and greater surface properties than Shiroodi isolates. The results showed the surface hydrophobicities of rice bran protein were greater than casein and ovalbumin and lower than other proteins such as bovine serum albumin. Water and oil absorption capacities were 1.03 and 1.66 for Tarom and 87.3 and 75.3 for Shiroodi, respectively. The bulk densities of Tarom and Shiroodi were also 0.55 and 0.53 g/mL, which make them suitable for weaning food and other industrial applications. As a result, these rice bran proteins showed higher hydrophobicity than that of other rice bran protein varieties as well as more functionality. Thus, they have good potential in the food and pharmaceutical industries.  相似文献   
69.
This paper examines production costs and returns of sutchi catfish (Pangasianodon hypophthalmus) aquaculture under three different farming systems in Bangladesh. Based on the production technology, sutchi catfish farming is classified as extensive, semi‐intensive and intensive. Results showed that sutchi catfish farming is profitable irrespective of the level of intensification and in all three instances the cost of feed dominated the variable costs of production. The average annual production costs were estimated at US$5217 ha?1 in intensive farming, while US$2694 ha?1 in semi‐intensive and US$981 ha?1 in extensive farming. Despite the higher production costs per hectare, the average annual net return was higher in intensive farming (US$3364), compared with semi‐intensive (US$2048) and extensive (US$1099) farming. The average annual production per hectare under intensive farming conditions (13 945 kg) was higher than semi‐intensive (7705 kg) and extensive (3380 kg) farming mainly due to higher levels of inputs, including seed, feed, fertilizer and labour. However, the Cobb–Douglas production function model suggests that inputs are inefficiently used in the intensive farming system. Conversely, there is enough scope to increase the production and income from the semi‐intensive and extensive farming systems by using more inputs.  相似文献   
70.
Bangladesh experiences some of the most severe impacts of climate change, with impacts already evident in the coastal regions. Recent data shows that around 32% of the coastal communities in Bangladesh are affected by climate‐induced hazards each year. In 2011, 64% among them were displaced locally and 27% were displaced to other locations in Bangladesh. It requires comprehensive and viable polices and planning to meet the challenges of managing a large number of displaced people. In this context, this paper reviews and investigates the effectiveness of current governance frameworks to address migration of affected communities. It argues that migration can be an effective way to cope with environmental shocks. Finally, it discusses policy imperatives for effective protection of people displaced by climate risks with a special reference to adopting a human rights‐based approach in law and policy making for climate‐induced migration.  相似文献   
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