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71.
Regionally specific sustainability processes that account for diverse environments and populations and that integrate social, economic, political and ecological spheres are being developed in Western Australia. A coordinated commitment to sustainability principles and a participatory philosophy by the state and local governments is necessary. This requires a transformation of the public service, from a director of passive programmes and laws to a facilitator of community projects and outcomes, towards an enabling state. An international participatory paradigm provides an array of concepts and methods for local and regional communities in partnership with government and industry to achieve this. Participatory methodologies are utilised successfully around the globe to create an institutional framework that facilitates a process of dialogue, partnership, networking, learning and managing change. This paper examines the potential contribution of a participatory approach to improve the participatory capacity of regional communities and both local and state governments towards the facilitation of regional sustainability processes.  相似文献   
72.
This paper explores the extent to which Western approaches to public involvement in environmental impact assessment (EIA) have been transferred to Vietnam, constraints on their use, and their appropriateness for the Vietnamese context. The research is based on an analysis of the public involvement content found in 26 EIA reports from development banks and interviews with 26 key informants. The study found that public involvement in Vietnam is generally technocratic, expert-driven and non-transparent, similar to the early days of EIA in the West and emerging economies. Public involvement usually occurs through authorised state channels such as commune leaders, mass organisations and professional organisations. The lack of a participatory culture for EIA, the nascent nature of grassroots democracy in the country, and Vietnamese cultural norms regarding respect for authority provide a challenging context for involving the public in EIA. The paper concludes by offering a number of suggestions for culturally appropriate public involvement at a time when Vietnam has just introduced mandatory public consultation for EIAs.  相似文献   
73.
Pot experiments were carried out to investigate the potential of phytoremediation with the arsenic hyperaccumulator Pteris vittata in a range of soils contaminated with As and other heavy metals, and the influence of phosphate and lime additions on As hyperaccumulation by P. vittata. The fern was grown in 5 soils collected from Cornwall (England) containing 67-4550 mg As kg(-1) and different levels of metals. All soils showed a similar distribution pattern of As in different fractions in a sequential extraction, with more than 60% of the total As being associated with the fraction thought to represent amorphous and poorly-crystalline hydrous oxides of Fe and Al. The concentration of As in the fronds ranged from 84 to 3600 mg kg(-1), with 0.9-3.1% of the total soil As being taken up by P. vittata. In one soil which contained 5500 mg Cu kg(-1) and 1242 mg Zn kg(-1), P. vittata suffered from phytotoxicity and accumulated little As (0.002% of total). In a separate experiment, neither phosphate addition (50mg P kg(-1) soil) nor liming (4.6 g CaCO3 kg(-1) soil) was found to affect the As concentration in the fronds of P. vittata, even though phosphate addition increased the As concentration in the soil pore water. Between 4 and 7% of the total soil As was taken up by P. vittata in 4 cuttings in this experiment. The results indicate that P. vittata can hyperaccumulate As from naturally contaminated soils, but may be suitable for phytoremediation only in the moderately contaminated soils.  相似文献   
74.
Complexing of metals by organic matter can strongly influence their biological activity in the environment. The extent of copper complex formation by soluble organic matter extracted from an organic soil, a clay, and two sandy loams, was measured under identical conditions using two independent experimental methods. The results in every case fitted equations similar to Langmuir two-surface isotherms, but the values of complexing capacity and complexing strength were not the same for the organic matter from the four soils, and so were unsuitable for use in computer programs intended to predict concentrations of individual copper species in soil solutions. These concentrations can, however, be predicted by an empirical relationship between free and total copper at a constant pH and ionic strength.  相似文献   
75.
The process of reproductive maturation and egg release was examined in the temperate shelf squid Nototodarus gouldi. The energy allocation between somatic and reproductive growth from juvenile to mature adult was investigated throughout the life span to determine the underlying energetic strategy adopted by individuals. The relative weight of the mantle, fin and digestive gland remained unchanged during ovarian development, with no significant correlations found between the mantle length (ML)-gonad residuals and the ML-mantle (r=0.01, P>0.05), ML-fin (r=0.07, P>0.05) and ML-digestive gland (r=0.07, P>0.05) residuals. This suggested that energy was not being diverted away from somatic growth during sexual development, and consequently neither muscle nor digestive gland was being utilised as an energy store. Since squid in all maturity stages contained some food in their stomachs (e.g. 66.7% of mature animals), it is likely that the cost of maturation in this species is largely being met by food intake. The energy investment in reproductive tissues was relatively low (mean gonado-somatic index for mature individuals was 9.29% - 0.40%), indicating that only small amounts of energy were being allocated to reproduction at anyone point in time, which is characteristic of a multiple-spawning strategy. Furthermore, oviduct weight was not correlated with body size (r=0.256, P>0.05), suggesting that eggs are not stored for a single release. In all except one individual, ovary weight was consistently heavier than oviduct weight, suggesting that the ovary is not being depleted of oocytes as mature ova move into the oviducts. Additionally, the ovaries of mature females contained a range of oocyte sizes with discrete peaks, indicating a continued production and development of oocyte cohorts. The presence of some individuals with stretched empty oviducts is further evidence that the reproductive strategy of N. gouldi is slow and steady, with eggs possibly being released in discrete batches over a period of time.  相似文献   
76.
ABSTRACT: The U.S. Geological Survey modular, three-dimensional, finite-difference, ground-water flow model, commonly called MODFLOW, has been modified so that it can read and write files used by a geographic information system (GIS). The modified model program is called MODFLOWARC. The design of MODFLOWARC parallels the design of the ground-water flow model program MODFLOW. The names of the variables, modules, and submodules used to explain the operations of MODFLOWARC were derived from the names used in MODFLOW. During the data input phase, MODFLOWARC reads array control records similar to the original control records of MODFLOW, except an additional variable is added. This additional variable is the name of the computer files containing array data in GIS format. Data output is achieved by setting record/input flags and by supplying a variable that is the name of the directory where the output data will be recorded. The modifications to MODFLOW were minimized so that MODFLOWARC will operate on an existing ground-water flow model without modifying array control records.  相似文献   
77.
ABSTRACT: The 48 h survival of emigrating juvenile blueback herring (Alosa aestivalis) was estimated at 96 ± 6.7 percent in passage through a Kaplan-type turbine and at 88.3 ± 10.7 percent (90 percent confidence interval) over a spillway (3.7 m high and spillage of 1.2 m3/s) of a low-head hydro darn (8.3 m). These results suggest that diversion of juvenile alosids over spillways may not be assumed to be a totally benign strategy without obtaining site-specific data. A remarkable similarity in survival rates of fish observed through turbine routes in this study and others suggests that these trends may be common. However, due to a lack of sufficient data, such a conclusion cannot be made for survival over spillways.  相似文献   
78.
The paper reports the findings of a small scale study comparing the personal travel patterns of households of similar type, living in a rural area and a small urban area of the Dublin city region. The study found that the rural area was less environmentally sustainable as a result of the extent of its dependency on the motor car, an inefficient and polluting transport mode. The study also provided evidence that the quality of life in the rural area was adversely affected by aspects of car dependency. There appeared to be a higher risk of traffic accident, rural dwellers used less healthy forms of transport, they suffered restricted mobility and, as a consequence enjoyed a less varied social life than their urban counterparts.  相似文献   
79.
To determine whether sludge applications to soil would lead in the short term to toxicity to plants and trace metal leaching to ground water, we studied the fate of some trace and major elements in a brown soil-meadow system just after repeated sewage sludge applications. The main pathways were quantified over a 37-mo period with undisturbed monolith lysimeters including two controls, four lysimeters treated with 3 x 100 m3 ha-1, and four with 3 x 400 m3 ha-1 of sewage sludge. In drainage waters the effect was limited in time and, in the case of NO3-N and Cl, delayed by 1 to 4 mo and lasted several months before returning to background conditions. Nickel and Cu concentrations in solution increased also after sludge application and had not return to background conditions after 20 mo. Trace metal concentrations did not reach toxic levels in herbage and N, Cu, Cd, and Zn concentrations were correlated with the first sludge input only. Calculated over a 37-mo period, total element output was significantly increased for Ca, NO3-N, and Ni only, because of the time-dependent response to sludge application and high variability between replicates. Output was maximal for Cd, with 1.5% of total input for the 100 m3 ha-1 treatment. Particulate matter in drainage water accounted for an average of 20% of trace metal leaching. The main long-term risk was the rapid increase in trace metal concentrations in the topsoil, which may eventually lead to toxic levels in herbage.  相似文献   
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