Municipal solid waste production and composition in Finland—Changes in the period 1960–2002 and prospects until 2020

Waste reduction was recognised as the main goal of waste management policy in the EU in the 1990s. Although knowledge of past waste generation is essential for effective waste reduction policy there are no comprehensive statistics on the past development of municipal solid waste (MSW) production. MSW management is currently under turmoil in many EU countries as the requirements of the EC landfill directive (1999/31/EC) are set into force. In this study, the production and composition of MSW in Finland between 1960 and 2002 is presented using historical data. The impact of population, affluence and technology on MSW production are analysed using the IPAT equation and three scenarios are constructed until year 2020. The results are compared with national future targets on MSW production. Production of MSW increased in Finland until 1990, declined to year 1997, increased to 2000 and then declined again. The share of organic and plastic waste increased over the study period while the share of paper and cardboard declined. The results suggest that so far national targets on MSW reduction have been set fairly low. Moreover, our scenarios depict a wide range of future MSW production, even though the time horizon is not longer than 15 years into the future. In order to narrow this range, continuous improvement of the statistics of MSW is essential.     

Nonpoint-Source Agricultural Hazard Index: A Case Study of the Province of Cremona, Italy

This paper reports the results of a study aimed at the evaluation of the hazard level of farming activities in the province of Cremona, Italy, with particular reference to groundwater. The applied methodology employs a parametric approach based on the definition of potential hazard indexes (nonpoint-source agricultural hazard indexes, NPSAHI). Two categories of parameters were considered: the hazard factors (HF), which represent all farming activities that cause or might cause an impact on groundwater (use of fertilizers and pesticides, application of livestock and poultry manure, food industry wastewater, and urban sludge), and the control factors (CF), which adapt the hazard factor to the characteristics of the site (geographical location, slope, agronomic practices, and type of irrigation). The hazard index (HI) can be calculated multiplying the hazard factors by the control factors and, finally, the NPSAHI are obtained dividing HI into classes on a percentile basis using a scale ranging from 1 to 10. Organization, processing, and display of all data layers were performed using the geographical information system (GIS) ArcView and its Spatial Analyst extension. Results show that the potential hazard of groundwater pollution by farming activities in the province of Cremona falls mainly in the fifth class (very low hazard).     

加勒比海海洋保护区的娱乐性水下呼吸器潜水活动:使用者支付费用吗?

引言 建立海洋保护区的好处[1]是众所周知的,特别是对于珊瑚礁来说.通过理论上完全禁止在选定海域内进行任何形式的捕鱼活动,由此对捕鱼压力的降低一般可以保持以往目标鱼类[2～4]种群的数量和多样性,导致原来从渔场中消失的物种重新出现[5],而且大大提高大型掠食性鱼类的数量[6].     

Passing the buck: resource defence,lek breeding and mate choice in fallow deer

Summary Lek breeding systems, where males defend small, clustered mating territories, are thought to occur where the distribution of females is heavily clumped but males are unable to defend resources used by females. In this paper, we describe a breeding system in fallow deer where males are able to defend resources used by females but the most successful bucks instead defend small territories on a traditional mating ground; where the lek is sited in an area not heavily used by females at other times of year and is visited primarily by females in or close to oestrus; and where mating success on the lek is related to territory position and to male phenotype but not to the resources available on different lek territories. Comparisons with other ungulates suggest that lek breeding species fall into two groups: those where leks are regularly visited by herds of females many of which are not in oestrus and those, like fallow deer, where leks are visited primarily by oestrous females. In the latter species, it is unlikely that females visit the lek for ecological reasons.     

Measured concentrations of herbicides and model predictions of atrazine fate in the Patuxent River estuary

The environmental fate of herbicides in estuaries is poorly understood. Estuarine physical transport processes and the episodic nature of herbicide release into surface waters complicate interpretation of water concentration measurements and allocation of sources. Water concentrations of herbicides and two triazine degradation products (CIAT [6-amino-2-chloro-4-isopropylamino-s-triazine] and CEAT [6-amino-2-chloro-4-ethylamino-s-triazine]) were measured in surface water from four sites on 40 d from 4 Apr. through 29 July 19% in the Patuxent River estuary, part of the Chesapeake Bay system. Atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine) was most persistent and present in the highest concentrations (maximum = 1.29 microg/L). Metolachlor [2-chloro-6'-ethyl-N-(2-methoxy-1-methylethyl)-o-acetoluidide], CIAT, CEAT, and simazine (1-chloro-3,5-bisethylamino-2,4,6-triazine) were frequently detected with maximum concentration values of 0.61, 1.1, 0.76, and 0.49 microg/L, respectively. A physical transport model was used to interpret atrazine concentrations in the context of estuarine water transport, giving estimates of in situ degradation rates and total transport. The estimated half-life of atrazine in the turbid, shallow upper estuary was t(1/2) = 20 d, but was much longer (t(1/2) = 100 d) in the deeper lower estuary. Although most (93%) atrazine entered the estuary upstream via the river, simulations suggested additional inputs directly to the lower estuary. The total atrazine load to the estuary from 5 April to 15 July was 71 kg with 48% loss by degradation and 31% exported to the Chesapeake Bay. Atrazine persistence in the estuary is directly related to river flows into the estuary. Low flows will increase atrazine residence time in the upper estuary and increase degradation losses.     

Dredged Illinois River sediments: plant growth and metal uptake

Sedimentation of the Illinois River in central Illinois has greatly diminished the utility and ecological value of the Peoria Lakes reach of the river. Consequently, a large dredging project has been proposed to improve its wildlife habitat and recreation potential, but disposal of the dredged sediment presents a challenge. Land placement is an attractive option. Previous work in Illinois has demonstrated that sediments are potentially capable of supporting agronomic crops due to their high natural fertility and water holding capacity. However, Illinois River sediments have elevated levels of heavy metals, which may be important if they are used as garden or agricultural soil. A greenhouse experiment was conducted to determine if these sediments could serve as a plant growth medium. A secondary objective was to determine if plants grown on sediments accumulated significant heavy metal concentrations. Our results indicated that lettuce (Lactuca sativa L.), barley (Hordeum vulgare L.), radish (Raphanus sativus L.), tomato (Lycopersicon lycopersicum L.), and snap bean (Phaseolus vulagaris L. var. humillis) grown in sediment and a reference topsoil did not show significant or consistent differences in germination or yields. In addition, there was not a consistent statistically significant difference in metal content among tomatoes grown in sediments, topsoil, or grown locally in gardens. In the other plants grown on sediments, while Cd and Cu in all cases and As in lettuce and snap bean were elevated, levels were below those considered excessive. Results indicate that properly managed, these relatively uncontaminated calcareous sediments can make productive soils and that metal uptake of plants grown in these sediments is generally not a concern.     

Tree species for recovering nitrogen from dairy-farm effluent in New Zealand

Land treatment of dairy-farm effluent is being widely adopted as an alternative to disposal into surface waters in New Zealand. This study investigated water balances and associated N leaching from short-rotation forest (SRF) species irrigated with dairy-farm effluent. Single trees were grown in lysimeters filled with Manawatu fine sandy loam (mixed mesic Dystric Eutrochrept). Dairy-farm effluent was applied during two irrigation periods at 21.5 mm wk(-1) with a total loading equivalent to 870 kg N ha(-1) occurring over 17 mo. Following tree harvest in April 1997, measurements continued until August 1997 to monitor tree reestablishment. Cumulative N leached did not differ between lysimeters in which evergreen Sydney blue gum (Eucalyptus saligna Sm.) and shining gum [Eucalyptus nitens (H. Deane & Maiden) Maiden] and deciduous kinu-yanagi (Salix kinuyanagi Kimura) were grown. Leachate N concentrations of all treatments were on average higher than the New Zealand drinking water standard of 11.3 mg N L(-1). The E. nitens and S. kinuyanagi treatments leached 33 and 35 kg N ha(-1) yr(-1) in 1996 following application of 236 kg N ha(-1) during the first irrigation season. Leaf area was strongly correlated to evapotranspiration, drainage volume, and nitrogen leached. The majority of leaching in the tree treatments occurred after harvest. Reducing the leaching in the regrowth phase may be achieved through timing harvest in the spring when growth rates are higher and leaching potential is lower. Based on N uptake rates observed in this study and average pond discharge, a plantation of 5.4 ha would be required for N recovery on a typical dairy farm in New Zealand.     

Brownfield redevelopment as a smart growth option in the United States

An evaluation is made of brownfields redevelopment as a smart growth policy compared to purchase of land, restrictive growth policies, changing transportation patterns, promoting compact development designs on the metropolitan fringe, and regional government. In the US brownfields redevelopment has clear advantages with regard to environmental protection, moral imperative, and government and special interest reactions. Its rank with regard to economic feasibility, ability to respond to changes in technology, and public reaction are not clear. A great deal more research is needed, especially about the costs of brownfield redevelopment and public preferences for housing type and location to be certain about brownfields redevelopment as a viable smart growth option.     

Simulated predator extinctions: predator identity affects survival and recruitment of oysters

The rate of species loss is increasing at a global scale, and human-induced extinctions are biased toward predator species. We examined the effects of predator extinctions on a foundation species, the eastern oyster (Crassostrea virginica). We performed a factorial experiment manipulating the presence and abundance of three of the most common predatory crabs, the blue crab (Callinectes sapidus), stone crab (Menippe mercenaria), and mud crab (Panopeus herbstii) in estuaries in the eastern United States. We tested the effects of species richness and identity of predators on juvenile oyster survival, oyster recruitment, and organic matter content of sediment. We also manipulated the density of each of the predators and controlled for the loss of biomass of species by maintaining a constant mass of predators in one set of treatments and simultaneously using an additive design. This design allowed us to test the density dependence of our results and test for functional compensation by other species. The identity of predator species, but not richness, affected oyster populations. The loss of blue crabs, alone or in combination with either of the other species, affected the survival rate of juvenile oysters. Blue crabs and stone crabs both affected oyster recruitment and sediment organic matter negatively. Mud crabs at higher than ambient densities, however, could fulfill some of the functions of blue and stone crabs, suggesting a level of ecological redundancy. Importantly, the strong effects of blue crabs in all processes measured no longer occurred when individuals were present at higher-than-ambient densities. Their role as dominant predator is, therefore, dependent on their density within the system and the density of other species within their guild (e.g., mud crabs). Our findings support the hypothesis that the effects of species loss at higher trophic levels are determined by predator identity and are subject to complex intraguild interactions that are largely density dependent. Understanding the role of biodiversity in ecosystem functioning or addressing practical concerns, such as loss of predators owing to overharvesting, remains complicated because accurate predictions require detailed knowledge of the system and should be drawn from sound experimental evidence, not based on observations or generalized models.