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41.
Petra Lasch Chris Kollas Joachim Rock Felicitas Suckow 《Regional Environmental Change》2010,10(2):83-94
Woody biomass generated in short-rotation coppice (SRC) plantations with aspen (Populus tremula L.) has good properties for bioenergy crop production: annual yields are high, labour input per year is low, and it is ecologically
valuable because of the multi-year rotation periods. Eastern Germany has a special advantage in producing bioenergy crops:
the former “agricultural cooperatives” built up quite large farms with, compared to Western Germany, comparatively large fields.
Therefore, a modelling study of the potential and the impacts of aspen SRC plantations in the five eastern federal states
of Germany under the recent climate and future climate projections was conducted. The ecophysiological forest growth model
4C was used to simulate the growth of aspen SRC plantations and their impacts on carbon in soils, and groundwater recharge,
on selected suitable areas currently under crops but with marginal site conditions for cropping. A clear signal to enhanced
growth condition over the whole area can be seen in the simulation of the mean annual woody biomass yield under conditions
of climate change, which increased from 7.47 t DW ha−1 a−1 under the recent climate to 9.26 t DW ha−1 a−1 at the end of the considered future period 2034–2055 under climate change. The mean soil carbon sequestration rate was 0.81 t C ha−1 a−1 under the recent climate and could rise up to 0.93 t C ha−1 a−1 under the assumption of climate change. On the other hand, the mean annual percolation rate, used as an indicator of impacts
on the regional water budget, will diminish under future climatic conditions. The results suggest that aspen SRC plantations
are a suitable contribution to regional CO2 mitigation and carbon sequestration under possible change of climate, but that negative impacts on the regional water budget
are possible. 相似文献
42.
Mark Gabriel Chris Knightes Robin Dennis Ellen Cooter 《Environmental Modeling and Assessment》2014,19(6):451-465
There has been extensive analysis of Clean Air Act Amendment (CAAA) regulation impacts to changes in atmospheric nitrogen deposition; however, few studies have focused on watershed nitrogen transfer particularly regarding long-term predictions. In this study, we investigated impacts of CAAA NOx emissions on the fate and transport of nitrogen for two watersheds in the Neuse River Basin. We applied the Soil and Water Assessment Tool (SWAT) using simulated deposition rates from the Community Multiscale Air Quality (CMAQ) model. Two scenarios were investigated: one that considered CAAA emission controls in CMAQ simulation (with) and a second that did not (without). By 2020, results showed a 70 % drop in nitrogen discharge for the Little River watershed and a 50 % drop for the Nahunta watershed from 1990 levels under the with-CAAA scenario. Denitrification and plant nitrogen uptake played important roles in nitrogen discharge from each watershed. Nitrogen watershed response time to a change in atmospheric nitrogen deposition was 4 years for Nahunta and 2 years for Little River. We attribute these differences in nitrogen response time to contrasts in agricultural land use and diversity of crop types. Soybean, hay, and corn land covers had comparatively longer response times to changes in atmospheric deposition. The studied watersheds demonstrate relatively large nitrogen retention: ≥80 % of all delivered nitrogen. 相似文献
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45.
Chris Bryant 《补救:环境净化治理成本、技术与工艺杂志》1995,6(1):111-113
46.
Incident reporting systems are playing an increasingly important role in the development and maintenance of safety-critical applications. The perceived success of the FAA's Aviation Safety Reporting System (ASRS) and the FDA's MedWatch has led to the establishment of similar national and international schemes. These enable individuals and groups to report their safety concerns in a confidential or anonymous manner. Unfortunately, many of these systems are becoming victims of their own success. The ASRS and MedWatch have both now received over 500,000 submissions. In consequence, the administrators of incident reporting systems increasingly rely upon software tools to support the administration of their systems. In the past, these systems have relied upon ad hoc applications of conventional database technology. However, there are several reasons why this technology is inadequate for many large-scale reporting schemes. In particular, the problems of query formation often result in poor precision and recall. This, in turn, has profound implications for safety-critical applications. Users may fail to identify similar incidents within national or international collections. These ad hoc approaches also neglect the opportunities provided by recent developments in computer assisted interviewing and in the monitoring of retrieval activities to build models of user behavior. These techniques offer a number of potential benefits. For instance, it is possible to automatically detect potential biases in the way that investigators analyze particular incidents. 相似文献
47.
Rational, cost-effective provision of mission-critical environmental management information remains elusive for almost all large enterprises. Even among the best performing companies—best performing from the perspectives of profitability, quality and/or environmental stewardship—environmental management information systems (EMIS) are usually comprised of dozens to hundreds of individual, isolated applications that require costly data capture, training, and maintenance. This article, the first of two, will discuss ways to coordinate information infrastructures with strategic goals and business processes. 相似文献
48.
Chris FitzGerald 《环境质量管理》1994,4(2):21-33
Successful implementation of environmental management information systems (EMIS) has become essential to the success of total quality environmental management (TQEM) programs. Effective TQEM programs will be early indicators of which companies survive and thrive in today's competitive business environment. Highly competitive industries such as chemicals, electronics, and oil and gas are becoming very effective in cooperating to develop metrics, models, and tools that are based on business processes rather than regulatory edicts. Now electric power companies, newly exposed to market competition, are starting to develop and implement these metrics, standards, and tools. That industry provides a model for joining TQEM and EMIS. 相似文献
49.
Rapid interphase analysis for prenatal diagnosis of translocation carriers using subtelomeric probes
Mark J. Pettenati Chris Von Kap-Herr Bethy Jackle Peggy Bobby Philip Mowrey Stuart Schwartz P. Nagesh Rao Jon Rosnes 《黑龙江环境通报》2002,22(3):193-197
Interphase fluorescence in situ hybridization (FISH) has become an accepted laboratory technique for the rapid and preliminary prenatal assessment of chromosome aneuploidy. The introduction of subtelomeric FISH probes now allows for the molecular–cytogenetic analysis of terminal chromosome rearrangements. In a prospective study, we examined the prenatal use of subtelomeric probes on interphase cells to rapidly detect the carrier status of a fetus when a parent carried a known reciprocal or Robertsonian chromosome translocation. Three of the cases were identified as being abnormal. All cases were confirmed by routine cytogenetic analysis. These findings clearly demonstrated the utility of this technique and these probes to rapidly and correctly identify balanced and unbalanced chromosome anomalies of a fetus that could result from parental translocations. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
50.
Beekman M Good G Allsopp MH Radloff S Pirk CW Ratnieks FL 《Die Naturwissenschaften》2002,89(10):479-482
In the Cape honey bee Apis mellifera capensis, workers lay female eggs without mating by thelytokous parthenogenesis. As a result, workers are as related to worker-laid eggs as they are to queen-laid eggs and therefore worker policing is expected to be lower, or even absent. This was tested by transferring worker- and queen-laid eggs into three queenright A. m. capensis discriminator colonies and monitoring their removal. Our results show that worker policing is variable in A. m. capensis and that in one colony worker-laid eggs were not removed. This is the first report of a non-policing queenright honey bee colony. DNA microsatellite and morphometric analysis suggests that the racial composition of the three discriminator colonies was different. The variation in policing rates could be explained by differences in degrees of hybridisation between A. m. capensis and A. m. scutellata, although a larger survey is needed to confirm this. 相似文献