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111.
Ben L. O’Connor Yuki Hamada Esther E. Bowen Mark A. Grippo Heidi M. Hartmann Terri L. Patton Robert A. Van Lonkhuyzen Adrianne E. Carr 《Environmental monitoring and assessment》2014,186(11):7075-7095
Large areas of public lands administered by the Bureau of Land Management and located in arid regions of the southwestern United States are being considered for the development of utility-scale solar energy facilities. Land-disturbing activities in these desert, alluvium-filled valleys have the potential to adversely affect the hydrologic and ecologic functions of ephemeral streams. Regulation and management of ephemeral streams typically falls under a spectrum of federal, state, and local programs, but scientifically based guidelines for protecting ephemeral streams with respect to land-development activities are largely nonexistent. This study developed an assessment approach for quantifying the sensitivity to land disturbance of ephemeral stream reaches located in proposed solar energy zones (SEZs). The ephemeral stream assessment approach used publicly-available geospatial data on hydrology, topography, surficial geology, and soil characteristics, as well as high-resolution aerial imagery. These datasets were used to inform a professional judgment-based score index of potential land disturbance impacts on selected critical functions of ephemeral streams, including flow and sediment conveyance, ecological habitat value, and groundwater recharge. The total sensitivity scores (sum of scores for the critical stream functions of flow and sediment conveyance, ecological habitats, and groundwater recharge) were used to identify highly sensitive stream reaches to inform decisions on developable areas in SEZs. Total sensitivity scores typically reflected the scores of the individual stream functions; some exceptions pertain to groundwater recharge and ecological habitats. The primary limitations of this assessment approach were the lack of high-resolution identification of ephemeral stream channels in the existing National Hydrography Dataset, and the lack of mechanistic processes describing potential impacts on ephemeral stream functions at the watershed scale. The primary strength of this assessment approach is that it allows watershed-scale planning for low-impact development in arid ecosystems; the qualitative scoring of potential impacts can also be adjusted to accommodate new geospatial data, and to allow for expert and stakeholder input into decisions regarding the identification and potential avoidance of highly sensitive stream reaches. 相似文献
112.
Guangxing Wang George Gertner Alan Anderson Heidi Howard 《Environmental management》2009,44(4):810-823
The land management of US Army installations requires information on land conditions and their history for planning future
military training activities and allocation of land repair. There is thus a strong need for methodology development to estimate
the land conditions and cumulative military training impacts for the purpose of repair and restoration. In this study, we
simulated at Fort Riley, USA, spatial patterns and temporal dynamics of military training impacts on land conditions quantified
as percent ground cover using an image-aided spatial conditional co-simulation algorithm. Moreover, we estimated the historical
percent ground cover as a measure of the cumulative impacts, and then calculated the allocation of land repair and restoration
based on both current and historical land conditions. In addition, we developed a loss function method for allocation of land
repair and restoration. The results showed: (1) this co-simulation algorithm reproduced spatial and temporal variability of
percent ground cover and provided estimates of uncertainties with the correlation coefficients and root mean square errors
between the simulated and observed values varying from 0.63 to 0.88 and from 23% to 78%, respectively; (2) with and without
the cumulative impacts, the obtained spatial patterns of the land repair categories were similar, but their land areas differed
by 5% to 40% in some years; (3) the combination of the loss function with the co-simulation made it possible to estimate and
computationally propagate the uncertainties of land conditions into the uncertainties of expected cost loss for misallocation
of land repair and restoration; and (4) the loss function, physical threshold, and probability threshold methods led to similar
spatial patterns and temporal dynamics of the land repair categories, however, the loss function increased the land area by
5% to 30% for intense and moderate repairs and decreased the area by 5% to 30% for no repairs and light repairs for most of
the years. This approach provided the potential to improve and automate the existing land rehabilitation and maintenance (LRAM)
system used for the land management of the U.S. Army installations, and it can be applied to the management of other civil
lands and environments. In conclusion, this study overcame the important gaps that exist in the methodological development
and application for simulating land conditions and cumulative impacts due to human activities, and also in the methods for
the allocation of land for repair and restoration. 相似文献
113.
Hartmut Koehler Tobias Frische Ingo Dobner Peter Behrend Maike Schaefer Heidi Taubner Bernd Jastorff Jürgen Warrelmann Ulrich Walter 《Environmental Sciences Europe》2001,13(5):291-300
Results of a field experiment (please refer to Warrelmann et al. 2000a) document TNT-degradation and regeneration after the establishment of a phytoremediation. Various approaches are included in a complex monitoring system, which are conducted in the field (nitroaromatics in soil, seepage water, and plants; soil fauna; soil fungi; decomposition) as well as in the lab (a battery of 6 biotests). The data document a high heterogeneity of the TNT-contamination, a rapid initial decrease and a mediocre displacement of nitroaromatics in plants and seepage water. The initial rapid transformation of TNT to aminodinitrotoluenes ceases significantly after 3 months. Results of the biotest battery allow a sophisticated assessment of soil toxicity; the results from the soil ecological field investigations make the long-term effects of TNT-contamination likely. In a third part of the series of articles, a synopsis and judgement of the project will be delivered. 相似文献
114.
Amir H Pakpour Isa Mohammadi Zeidi Mohammad Mahdi Emamjomeh Saeed Asefzadeh Heidi Pearson 《Waste management (New York, N.Y.)》2014,34(6):980-986
Understanding the factors influencing recycling behaviour can lead to better and more effective recycling programs in a community. The goal of this study was to examine factors associated with household waste behaviours in the context of the theory of planned behaviour (TPB) among a community sample of Iranians that included data collection at time 1 and at follow-up one year later at time 2. Study participants were sampled from households under the coverage of eight urban health centers in the city of Qazvin. Of 2000 invited households, 1782 agreed to participate in the study. A self-reported questionnaire was used for assessing socio-demographic factors and the TPB constructs (i.e. attitude, subjective norms, perceived behavioural control, and intention). Furthermore, questions regarding moral obligation, self-identity, action planning, and past recycling behaviour were asked, creating an extended TPB. At time 2, participants were asked to complete a follow-up questionnaire on self-reported recycling behaviours. All TPB constructs had positive and significant correlations with each other. Recycling behaviour at time 1 (past behaviour) significantly related to household waste behaviour at time 2. The extended TPB explained 47% of the variance in household waste behaviour at time 2. Attitude, perceived behavioural control, intention, moral obligation, self-identity, action planning, and past recycling behaviour were significant predictors of household waste behaviour at time 2 in all models. The fact that the expanded TPB constructs significantly predicted household waste behaviours holds great promise for developing effective public campaigns and behaviour-changing interventions in a region where overall rates of household waste reduction behaviours are low. Our results indicate that educational materials which target moral obligation and action planning may be particularly effective. 相似文献
115.
We studied the lipid dynamics (lipid contents, classes and fatty acids) during oogenesis and early embryogenesis of 7 viviparous
and 3 oviparous deepwater chondrichthyans. Mature pre-ovulated ovarian follicles of all species were high in lipid content,
indicative of large energetic expenditure and high maternal investment. Larger lipid reserves were found in viviparous dogshark
(28–36% wet weight, ww) compared to oviparous chimaeras (19–24% ww) and catshark, F. boardmani (18% ww). Neutral lipids and monounsaturated fatty acids were the main source of lipidic energy during vitellogenesis and
gestation. For most species, there was a peak in total lipid content, levels of storage lipids and essential fatty acids at
time of ovulation. Interspecific variation of total lipid yolk reserves and lipid class profiles was largely explained by
differences in parity mode, reproductive (continuous vs. non-continuous oocytes development) strategy and depth-related physiological adaptations. Fatty acid profiles were less variable
among species with the most important fatty acids including: 16:0, 18:1ω9, 20:1ω9, 20:4ω6 and 22:6ω3. These findings provide
a greater biochemical understanding of different maternal-embryonic relationships among chondrichthyans, which can be used
as a baseline for subsequent comparative studies. 相似文献
116.
117.
Evaluating environmental education,citizen science,and stewardship through naturalist programs
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Adina M. Merenlender Alycia W. Crall Sabrina Drill Michelle Prysby Heidi Ballard 《Conservation biology》2016,30(6):1255-1265
Amateur naturalists have played an important role in the study and conservation of nature since the 17th century. Today, naturalist groups make important contributions to bridge the gap between conservation science and practice around the world. We examined data from 2 regional naturalist programs to understand participant motivations, barriers, and perspectives as well as the actions they take to advance science, stewardship, and community engagement. These programs provide certification‐based natural history and conservation science training for adults that is followed by volunteer service in citizen science, education, and stewardship. Studies in California and Virginia include quantitative and qualitative evaluation data collected through pre‐ and postcourse surveys, interviews, and long‐term tracking of volunteer hours. Motivations of participants focused on learning about the local environment and plants and animals, connecting with nature, becoming certified, and spending time with people who have similar interests. Over half the participants surveyed were over 50 years old, two‐thirds were women, and a majority reported household incomes of over $50,000 (60% in California, 85% in Virginia), and <20% of those surveyed in both states described themselves as nonwhite. Thus, these programs need to improve participation by a wider spectrum of the public. We interviewed younger and underrepresented adults to examine barriers to participation in citizen science. The primary barrier was lack of time due to the need to work and focus on career advancement. Survey data revealed that participants’ ecological knowledge, scientific skills, and belief in their ability to address environmental issues increased after training. Documented conservation actions taken by the participants include invasive plant management, habitat restoration, and cleanups of natural areas and streams. Long‐term data from Virginia on volunteer hours dedicated to environmental citizen science show an increase from 14% in 2007 to 32% in 2014. In general, participants in the naturalist programs we examined increased their content knowledge about ecosystems, had greater confidence in conserving them, and continued to engage as citizen scientists after completing the program. 相似文献
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120.
Enantiomeric ratios (ERs) and enantiomeric fractions (EFs) of a number of chiral organochlorine pesticides and PCB atropisomers were measured by chiral gas chromatography/mass spectrometry (GC/MS) in five standard (SRM) and certified (CRM) reference materials: SRM 1588a (organics in cod liver oil), SRM 1945 (organics in whale blubber), Marine Mammal Quality Assurance Exercise Control Material IV (NIST IV, organics in whale blubber), CRM trout, and CRM EC-5 (sediment). Target analytes were cis- and trans-chlordane, heptachlor exo-epoxide, oxychlordane, U82, MC5, MC6, MC7, o,p′-DDT, and PCB congeners 91, 95, 136, 149, 174, 176, and 183. Measured ERs and EFs are in close agreement with the few literature values reported for some of these analytes in SRMs and CRMs. Chiral PCB ERs and EFs measured by one-dimensional chiral GC/MS were similar to values measured using multidimensional chiral GC/MS. Non-racemic chiral compositions are in agreement with known uptake and biotransformation in the respective environmental matrices. These values should aid in the quality assurance/quality control methodologies for chiral environmental chemistry using standardized reference materials. 相似文献