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An Environmental Assessment (EA) is one of the steps within the Environmental Impact Assessment process. Birds are often used in EA to help decision makers evaluate potential human impacts from proposed development activities. A “sensitivity to human disturbance” index, created by Parker III et al. (1996) for all Neotropical species, is commonly considered an ecological indicator. However, this parameter was created subjectively and, for most species, there have been no rigorous field test to validate its effectiveness as such. Therefore, in this study, we aim to: (1) evaluate if, at the local scale, birds from forest patches in a human-modified landscape (HML) may differ in sensitivity from Parker's sensitivity classification; (2) evaluate the effectiveness of the species richness value at each sensitivity level as an ecological indicator; (3) gather information on how often and in which manner Parker's classification has been used in EA. To do so, bird sampling was performed in eight forest patches in a HML over one year. Then, we created a local sensitivity to disturbance using information about threat, endemism, spatial distribution and relative abundance of all species in the study area. We found that 37% of the forest birds showed different local sensitivity levels when compared with Parker's classification. Our results show that only the richness of high-sensitivity species from our local classification fitted the ecological indicator assumptions helping the environmental conditions evaluation of the studied patches. We conclude that species richness of each Parker's bird sensitivity levels do not necessarily perform as an ecological indicator at the local scale, and particularly in HML. Nevertheless, Parker's Neotropical bird sensitivity classification was used in 50% of EA we reviewed. In these, 76% assumed that it was an accurate ecological indicator of the local forest conditions for birds. The lack of clear criteria used in Parker's classification allows diverse interpretations by ornithologists, and there is no agreement about the ecological meaning of each sensitivity level and what environmental conditions each level may indicate of. Therefore, the use of Parker's classification in EA may jeopardize accurate interpretations of proposed anthropogenic impacts. Furthermore, because a bird species’ sensitivity often varies between locations, we argue that Parker's generalized classification of bird sensitivity should not be used as an indicator of forest environmental conditions in EA throughout HMLs in Neotropics. Rather, local bird ecological indices should be explored, otherwise, erroneous predictions of the anthropogenic impacts will continue to be common. 相似文献
4.
Ulrike Rosenfellner Franz Zehetner Martin H. Gerzabek 《Soil & Sediment Contamination》2009,18(6):685-687
Data from eight published studies were combined to show that the influence of traffic density on Pb contents in roadside soils increases with proximity to the road. 相似文献
5.
The European Common Agricultural Policy still follows its primary goals, i.e. quality food at affordable prices and a decent standard of living for farmers, fifty years after its adoption. Moreover, this policy adapts to the changing needs of society and the new challenges, mostly preservation of the environment, nature and biodiversity in rural areas. Although the Common Agricultural Policy receives the largest share of European budget, the funds are decreasing over time, especially direct payments, which aim to provide basic income support to farmers in the European Union. On the other hand, agri-environmental payments are gaining importance. Policy decision-makers should be interested in the question of impacts of growing eco-conditionality of agricultural spending. New insights would help them to be successful in achieving the goals of sustainable agriculture. The purpose of this paper is to estimate the impacts of production support payments and rural development payments on the quality of groundwater. We use the small EU country Slovenia as an example. The baseline indicators are the level of nitrates and pesticides in groundwater, while the impacts were estimated using spatial error model. The results show that direct payments, coupled subsidies and investment grants raise the level of pesticides in groundwater, but do not have any statistically significant impact on the level of nitrates in groundwater. Furthermore, we did not find any statistically significant effects of agri-environmental payments on decrease of groundwater pollution with nitrates. However, our findings revealed that agri-environmental payments are effective in reducing pesticides in groundwater, although only to a limited extent. These results imply a problem of insufficient targeting of agri-environmental measures on the one hand, and suggest that greening of direct payments is necessary and entirely justified. 相似文献
6.
Distribution of different forms of Zn in 16 acid alluvial rice growing soils of West Bengal (India) and their transformation
on submergence were studied. The results showed that more than 84% of total Zn occurred in the relatively inactive clay lattice-bound
form while a smaller fractionviz. 1.1, 1.6, 11.1 and 2.0 per cent of the total occurred as water-soluble plus exchangeable, organic complexed, amorphous sesquioxide-bound
and crystalline sesquioxide bound forms, respectively. All these four Zn forms showed significant negative correlations with
soil pH (r=−0.48**, −0.39*, −0.61** and −0.67**, respectively), while the latter two Zn forms showed significant positive correlations with Fe2O3 (0.68** and 0.88***) and Al2O3 (0.89*** and 0.75***) content of the soils. The different Zn forms were found to have positive and significant correlations amongst each other,
suggesting the existence of a dynamic equilibrium of these forms in soil.
Submergence caused an increase in the amorphous sesquioxide-bound form of Zn and a decrease in each of the other three forms.
The magnitude of such decreases in water-soluble plus exchangeable and crystalline sesquioxide-bound forms was found to be
correlated negatively with initial pH values of the soils and positively with the increase in the amorphous sesquioxide-bound
form, indicating their adsorption on the surface of the freshly formed hydrated oxides of Fe, which view was supported by
the existence of significant positive correlation between the increase in the amorphous sesquioxide-bound form of Zn and that
in AlCl3-extractable iron. The existence of a positive correlation between the decrease in crystalline sesquioxide-bound Zn and that
in Fe2O3 content in soil suggested that on waterlogging the soil Zn occluded in the cry talline sesquioxide was released as a result
of reduction of Fe2O3. 相似文献
7.
Model of ammonia volatilization from calcareous soils 总被引:2,自引:0,他引:2
A quantitative model of ammonia volatilization from the calcareous soil uppermost 1-cm layer was developed and tested. The
model accounts for the following processes: ammonium-ammonia equilibration in the soil solution, cation exchange between calcium
and ammonium which results in ammonium distribution between soil liquid and solid phases, nitrification of dissolved ammonium,
distribution of ammonia between liquid and gaseous phases and diffusion of gaseous ammonia in the soil air.
The combined effect of various characteristics such as soil pH, cation exchange capacity, water capacity and nitrification
rate on ammonia losses from various soil types have been studied. The model was validated against experimental results of
ammonia losses from different soils for its use as a predicting tool.
The model shows that most of ammonia losses can be explained by the interactive effect of high soil pH and low cation exchange
capacity. Computations show increased ammonia volatilization with decreasing soil water capacity. Increasing fertilizer application
rate has a small effect on percentage of ammonia losses. Increased nitrification rate and shorter “lag” period of nitrification
reduce ammonia losses considerably. Good agreement was obtained between model calculations and experimental results of ammonia
volatilization from 13 soils. 相似文献
8.
For three acid soils from Santa Catarina, Brazil, lime application and time of incubation with lime had little effect on the
adsorption of added phosphorus. In two soils with high contents of exchangeable aluminium, solution P and isotopically exchangeable
P were decreased by incubating with lime for 1 month: phosphorus was probably adsorbing on freshly precipitated aluminium
hydrous oxides. In one soil with less exchangeable aluminium, P in solution was increased by liming. After 23 months lime
increased solution and exchangeable P possibly due to crystallization of aluminium hydrous oxides reducing the number of sites
for P adsorption. All these changes were however small.
In a pot experiment, lime and phosphorus markedly increased barley shoot and root dry matter and P uptake. Although liming
reduced P availability measured by solution P, isotopically exchangeable P and resin extractable P, it increased phosphorus
uptake by reducing aluminium toxicity and promoting better root growth. The soil aluminium saturation was reduced by liming,
but the concentration of aluminium in roots changed only slightly. The roots accumulated aluminium without apparently being
damaged. 相似文献
9.
The growth response ofCalopogonium caeruleum, a leguminous covercrop in plantation agriculture, to inoculation with two vesicular-arbuscular mycorrhizal (VAM) fungi was
investigated in five phosphorus (P)-deficient soils supplied with various levels of rock phosphate. Significant shoot yield
increases over the uninoculated controls were obtained in most sterilised or unsterilised soils at all applied P levels, although
the inoculant VAM fungi differed in their effectiveness in the soils used. Responses in mycorrhizal root infections, P and
nitrogen (N) concentrations in tops and plant nodulation varied. The results are discussed in relation to the edaphic environment
of the mycorrhizal association. 相似文献
10.
Rice (IR 42) was grown on two soils differing in zinc status for 30 days with and without Zn under submerged conditions in
pots. The fate of soil zinc was characterized by extraction of the soil successively with copper acetate and sodium hypochlorite
and by EUF extraction. Most of the applied zinc was extracted by copper acetate and represented as complexed fraction. There
exists a close and significnat relation between Cu(OAc)2-extractable zinc and Zn extracted by EUF for 5 minutes at 50 volts (r=0.98). The EUF-extractable zinc and Cu(OAc)2-extractable zinc were significantly correlated with the zinc content in the plant (r=0.82). The data from this investigation
suggest the possibility of Zn fractionation with the EUF technique and the fractions obtained agree closely to those determined
by chemical methods. The results obtained indicate that Zn in soil is held by weak organic bonding and that the extractions
by Cu(OAc)2 and/or EUF-5 minutes serve as a useful basis for extimating zinc availability in rice soils. 相似文献