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Kosmos
Astronomia Astrofizyka
Inne

Kultura
Sztuka dawna i współczesna, muzea i kolekcje

Metoda
Metodologia nauk, Matematyka, Filozofia, Miary i wagi, Pomiary

Materia
Substancje, reakcje, energia
Fizyka, chemia i inżynieria materiałowa

Człowiek
Antropologia kulturowa Socjologia Psychologia Zdrowie i medycyna

Wizje
Przewidywania Kosmologia Religie Ideologia Polityka

Ziemia
Geologia, geofizyka, geochemia, środowisko przyrodnicze

Życie
Biologia, biologia molekularna i genetyka

Cyberprzestrzeń
Technologia cyberprzestrzeni, cyberkultura, media i komunikacja

Działalność
Wiadomości | Gospodarka, biznes, zarządzanie, ekonomia

Technologie
Budownictwo, energetyka, transport, wytwarzanie, technologie informacyjne

Environmental Research Letters

The Tibetan Plateau (TP) has fundamental ecological and environmental significance to China and Asia
through its influence on regional and continental climates. In recent years, climate warming has
caused unprecedented changes to land surface processes on the TP, which would unavoidably undermine
the ecological and environmental functions of the TP. Among the numerous land surface processes
potentially impacted by climate warming, the effect of vegetation greenness on surface energy
balance is one of the most critical, but has been long ignored. In this study, we investigated the
spatial and temporal patterns of land surface albedo (LSA) on the TP and evaluated the vegetation
greenness in relation to patterns of LSA. We found that LSA has been decreasing in most of the
vegetated grasslands on the TP from 2000 to 2013, as compared to a flat trend for desert area. The
regions where LSA has been decreasing were spatially correlated to areas of increased vegetation
greenness. Along r...

http://iopscience.iop.org/1748-9326/9/10/104001 2014/10/03 - 18:12

In this reply to ‘water footprint of marine protein consumption—aquaculture’s link to freshwater,’
we argue that Troell et al ’s calculation of the water footprint of marine aquaculture supports our
assumption that marine aquaculture requires a negligible amount of freshwater relative to the cost
of terrestrial crop substitution that is the focus of our analysis in ‘freshwater savings from
marine protein consumption’. We recognize that the water requirements of marine aquaculture could be
important for specific countries and will likely become more important at the global level as
aquaculture incorporates more terrestrially-based feeds and as aquaculture comprises a larger
percentage of total marine fish production. In response to Troell et al ’s comments on stagnant
capture fisheries, we clarify that our original discussion encompassed several possible future
conditions for these fisheries.

http://iopscience.iop.org/1748-9326/9/10/109002 2014/10/03 - 18:12

Overuse of surface water and an increasing reliance on nonrenewable groundwater resources have been
reported over various regions of the world, casting significant doubt on the sustainable water
supply and food production met by irrigation. To assess the limitations of global water resources,
numerous indicators have been developed, but they rarely consider nonrenewable water use. In
addition, surface water over-abstraction is rarely assessed in the context of human and
environmental water needs. Here, we perform a transient assessment of global water use over the
historical period 1960–2010 as well as the future projections of 2011–2099, using a newly developed
indicator: the blue water sustainability index (BlWSI). The BlWSI incorporates both nonrenewable
groundwater use and nonsustainable water use that compromises environmental flow requirements. Our
results reveal an increasing trend of water consumed from nonsustainable surface water and
groundwater resources over the histo...

http://iopscience.iop.org/1748-9326/9/10/104003 2014/10/03 - 18:12

In their article ‘Freshwater savings from marine protein consumption’ (2014 Environ. Res. Lett. 9
[http://dx.doi.org/10.1088/1748-9326/9/1/014005] 014005 ), Gephart and her colleagues analyzed how
consumption of marine animal protein rather than terrestrial animal protein leads to reduced
freshwater allocation. They concluded that future water savings from increased marine fish
consumption would be possible. We find the approach interesting and, if they only considered marine
capture fisheries, their analysis would be quite straightforward and show savings of freshwater.
However, both capture fisheries and aquaculture are considered in the analysis, and the fact that
marine aquaculture is assumed to have a zero freshwater usage, makes the analysis incomplete. Feed
resources used in marine aquaculture contain agriculture compounds, which results in a freshwater
footprint. To correct this shortcoming we complement the approach taken by Gephart and her colle...

http://iopscience.iop.org/1748-9326/9/10/109001 2014/10/03 - 18:12

The sensitivity of ecosystem gross primary production (GPP) to availability of water and
photosynthetically active radiation (PAR) differs among biomes. Here we investigated variations of
ecosystem light-use-efficiency (eLUE: GPP/PAR) and water-use-efficiency (eWUE:
GPP/evapotranspiration) among seven Australian eddy covariance sites with differing annual
precipitation, species composition and temperature. Changes to both eLUE and eWUE were primarily
correlated with atmospheric vapor pressure deficit (VPD) at multiple temporal scales across biomes,
with minor additional correlations observed with soil moisture and temperature. The effects of leaf
area index on eLUE and eWUE were also relatively weak compared to VPD, indicating an intrinsic
dependency of eLUE and eWUE on climate. Additionally, eLUE and eWUE were statistically different for
biomes between summer and winter, except eWUE for savannas and the grassland. These findings will
improve our understanding of how light- and w...

http://iopscience.iop.org/1748-9326/9/10/104002 2014/10/03 - 18:12

Smoke haze, caused by vegetation and peat fires in Southeast Asia, is of major concern because of
its adverse impact on regional air quality. We apply two different methods (a chemical transport
model and a Lagrangian atmospheric transport model) to identify the locations of fires contributing
to the increased mass concentration of particulate matter with diameters less than 2.5 μ m (PM 2.5 )
in Singapore over the period 2004–09. We find that fires in southern Sumatra account for the
greatest percentage of the total fire enhancement to PM 2.5 concentrations in Singapore (42–62%),
with fires in central Sumatra and Kalimantan contributing 21–35% and 14–15%, respectively.
Furthermore, we find that fires in these regions also increase PM 2.5 concentrations in other major
cities across Southeast Asia. Our results suggest that acting to reduce fires in southern and
central Sumatra (specifically in the eastern parts of the provinces of Jambi, South Sum...

http://iopscience.iop.org/1748-9326/9/9/094006 2014/09/27 - 07:01

Increased use of natural gas has been promoted as a means of decarbonizing the US power sector,
because of superior generator efficiency and lower CO 2 emissions per unit of electricity than coal.
We model the effect of different gas supplies on the US power sector and greenhouse gas (GHG)
emissions. Across a range of climate policies, we find that abundant natural gas decreases use of
both coal and renewable energy technologies in the future. Without a climate policy, overall
electricity use also increases as the gas supply increases. With reduced deployment of lower-carbon
renewable energies and increased electricity consumption, the effect of higher gas supplies on GHG
emissions is small: cumulative emissions 2013–55 in our high gas supply scenario are 2% less than in
our low gas supply scenario, when there are no new climate policies and a methane leakage rate of
1.5% is assumed. Assuming leakage rates of 0 or 3% does not substantially alter this finding. In our
res...

http://iopscience.iop.org/1748-9326/9/9/094008 2014/09/25 - 20:30

As the amount of reactive nitrogen (N) generated and emitted increases the amount of N deposition
and its contribution to eutrophication or harmful algal blooms in the coastal zones are becoming
issues of environmental concern. To quantify N deposition in coastal seas of China we selected six
typical coastal sites from North to South in 2011. Concentrations of NH 3 , HNO 3 , NO 2 ,
particulate NH 4 + (pNH 4 + ) and pNO 3 − ranged from 1.97– 4.88, 0.46 –1.22, 3.03 –7.09,
2.24 – 4.90 and 1.13–2.63 μ g N m −3 at Dalian (DL), Changdao (CD), Linshandao (LS), Fenghua (FH),
Fuzhou (FZ), and Zhanjiang (ZJ) sites, respectively. Volume-weighted NO 3 − –N and NH 4 + –N
concentrations in precipitation varied from 0.46 to 1.67 and 0.47 to 1.31 mg N L −1 at the six
sites. Dry, wet and total deposition rates of N were 7.8–23.1, 14.2–25.2 and 22.0 ...

http://iopscience.iop.org/1748-9326/9/9/095007 2014/09/25 - 20:30

The impacts of historical droughts and heat-waves on ecosystems are often considered indicative of
future global warming impacts, under the assumption that water stress sets in above a fixed high
temperature threshold. Historical and future (RCP8.5) Earth system model (ESM) climate projections
were analyzed in this study to illustrate changes in the temperatures for onset of water stress
under global warming. The ESMs examined here predict sharp declines in gross primary production
(GPP) at warm temperature extremes in historical climates, similar to the observed correlations
between GPP and temperature during historical heat-waves and droughts. However, soil moisture
increases at the warm end of the temperature range, and the temperature at which soil moisture
declines with temperature shifts to a higher temperature. The temperature for onset of water stress
thus increases under global warming and is associated with a shift in the temperature for maximum
GPP to warmer temperatur...

http://iopscience.iop.org/1748-9326/9/9/094011 2014/09/25 - 20:30

Grantham and Viers’ article 100 years of California’s water rights system: patterns, trends, and
uncertainty Grantham and Viers (2014 Environ. Res. Lett. 9 084012) makes valuable contributions by
mapping the disparities between California’s legal allocations of water and actual water
availability. This perspective article explains that those results both over- and understate the
potential for conflict, but they nevertheless provide useful information for water policy analysts
and educators. The results also provide compelling evidence of the need for water transfers and,
unfortunately, the practical difficulties associated with achieving those transfers.

http://iopscience.iop.org/1748-9326/9/9/091005 2014/09/25 - 20:30

Grantham and Viers’ article 100 years of California’s water rights system: patterns, trends, and
uncertainty Grantham and Viers (2014 Environ. Res. Lett. 9 084012) makes valuable contributions by
mapping the disparities between California’s legal allocations of water and actual water
availability. This perspective article explains that those results both over- and understate the
potential for conflict, but they nevertheless provide useful information for water policy analysts
and educators. The results also provide compelling evidence of the need for water transfers and,
unfortunately, the practical difficulties associated with achieving those transfers.

http://iopscience.iop.org/1748-9326/9/9/091005 2014/09/25 - 20:30

Because thousands of pharmaceutical and industrial compounds are in use today and distributed into
ecosystems via waste water, effective analysis of environmental risk needs to change as our
understanding of the complexity of ecosystem services grows. Klaminder et al (2014 Environ. Res.
Lett. 9 [http://dx.doi.org/10.1088/1748-9326/9/8/084003] 084003 ) now provide some important
observations on a methodological bias in standardized ecotoxicological tests. First, the authors
show that the formalized use of control species in risk assessment impacts how data is judged and
valued. Reducing quantitative uncertainty may improve the rigor of toxicological assays, but may
also increase the risk of missing likely ecosystem-scale impacts, essentially ‘throwing the baby out
with the bathwater’. Second, we should recognize the importance of integrating nature, complexity,
and dynamics across temporal and spatial scales in relation to the unintended consequence...

http://iopscience.iop.org/1748-9326/9/9/091004 2014/09/25 - 20:30

Because thousands of pharmaceutical and industrial compounds are in use today and distributed into
ecosystems via waste water, effective analysis of environmental risk needs to change as our
understanding of the complexity of ecosystem services grows. Klaminder et al (2014 Environ. Res.
Lett. 9 [http://dx.doi.org/10.1088/1748-9326/9/8/084003] 084003 ) now provide some important
observations on a methodological bias in standardized ecotoxicological tests. First, the authors
show that the formalized use of control species in risk assessment impacts how data is judged and
valued. Reducing quantitative uncertainty may improve the rigor of toxicological assays, but may
also increase the risk of missing likely ecosystem-scale impacts, essentially ‘throwing the baby out
with the bathwater’. Second, we should recognize the importance of integrating nature, complexity,
and dynamics across temporal and spatial scales in relation to the unintended consequence...

http://iopscience.iop.org/1748-9326/9/9/091004 2014/09/25 - 20:30

In this study we implement and evaluate a simple ‘hybrid’ forecast approach that uses constructed
analogs (CA) to improve the National Multi-Model Ensemble’s (NMME) March–April–May (MAM)
precipitation forecasts over equatorial eastern Africa (hereafter referred to as EA, 2°S to 8°N and
36°E to 46°E). Due to recent declines in MAM rainfall, increases in population, land degradation,
and limited technological advances, this region has become a recent epicenter of food insecurity.
Timely and skillful precipitation forecasts for EA could help decision makers better manage their
limited resources, mitigate socio-economic losses, and potentially save human lives. The ‘hybrid
approach’ described in this study uses the CA method to translate dynamical precipitation and sea
surface temperature (SST) forecasts over the Indian and Pacific Oceans (specifically 30°S to 30°N
and 30°E to 270°E) into terrestrial MAM precipitation forecasts over the EA region. In doing so,
this approach benefits ...

http://iopscience.iop.org/1748-9326/9/9/094009 2014/09/25 - 20:30

In this study we implement and evaluate a simple ‘hybrid’ forecast approach that uses constructed
analogs (CA) to improve the National Multi-Model Ensemble’s (NMME) March–April–May (MAM)
precipitation forecasts over equatorial eastern Africa (hereafter referred to as EA, 2°S to 8°N and
36°E to 46°E). Due to recent declines in MAM rainfall, increases in population, land degradation,
and limited technological advances, this region has become a recent epicenter of food insecurity.
Timely and skillful precipitation forecasts for EA could help decision makers better manage their
limited resources, mitigate socio-economic losses, and potentially save human lives. The ‘hybrid
approach’ described in this study uses the CA method to translate dynamical precipitation and sea
surface temperature (SST) forecasts over the Indian and Pacific Oceans (specifically 30°S to 30°N
and 30°E to 270°E) into terrestrial MAM precipitation forecasts over the EA region. In doing so,
this approach benefits ...

http://iopscience.iop.org/1748-9326/9/9/094009 2014/09/25 - 20:30

Cirrus clouds are known to play a key role in the climate system, but their overall effect on
Earth’s radiation budget is not yet fully quantified. The uncertainties are, in part, due to
ambiguities in cirrus extent or coverage. Here we show that despite careful filtering of cloudy
pixels, cirrus clouds have a clear statistical signature. This signature can be estimated by the
proximity to detectable cirrus clouds. Such a residual signature can affect retrievals that rely on
a cloud-free atmosphere, such as aerosol optical depth (AOD) or sea surface temperature. Analyzing
MODIS raw-data and products, we show a clear increase in the reflectance when approaching detectable
cirrus clouds. We estimated a mean increase in AOD of 0.03 ± 0.01 and a decrease in the
Angstrom-exponent of −0.22 ± 0.20 in the first kilometer around detectable cirrus. The effect decays
tenfold at a typical distance of 5.5 ± 1.8 km. Such trends confirm the contribution of large
particles that are likely to be ...

http://iopscience.iop.org/1748-9326/9/9/094010 2014/09/25 - 20:30

Cirrus clouds are known to play a key role in the climate system, but their overall effect on
Earth’s radiation budget is not yet fully quantified. The uncertainties are, in part, due to
ambiguities in cirrus extent or coverage. Here we show that despite careful filtering of cloudy
pixels, cirrus clouds have a clear statistical signature. This signature can be estimated by the
proximity to detectable cirrus clouds. Such a residual signature can affect retrievals that rely on
a cloud-free atmosphere, such as aerosol optical depth (AOD) or sea surface temperature. Analyzing
MODIS raw-data and products, we show a clear increase in the reflectance when approaching detectable
cirrus clouds. We estimated a mean increase in AOD of 0.03 ± 0.01 and a decrease in the
Angstrom-exponent of −0.22 ± 0.20 in the first kilometer around detectable cirrus. The effect decays
tenfold at a typical distance of 5.5 ± 1.8 km. Such trends confirm the contribution of large
particles that are likely to be ...

http://iopscience.iop.org/1748-9326/9/9/094010 2014/09/25 - 20:30

Observations and modeling studies indicate that enhanced vegetation activities over high latitudes
under an elevated CO 2 concentration accelerate surface warming by reducing the surface albedo. In
this study, we suggest that vegetation-atmosphere-sea ice interactions over high latitudes can
induce an additional amplification of Arctic warming. Our hypothesis is tested by a series of
coupled vegetation-climate model simulations under 2xCO 2 environments. The increased vegetation
activities over high latitudes under a 2xCO 2 condition induce additional surface warming and
turbulent heat fluxes to the atmosphere, which are transported to the Arctic through the atmosphere.
This causes additional sea-ice melting and upper-ocean warming during the warm season. As a
consequence, the Arctic and high-latitude warming is greatly amplified in the following winter and
spring, which further promotes vegetation activities the following year. We conclude that the ...

http://iopscience.iop.org/1748-9326/9/9/094007 2014/09/23 - 21:24

Building rural energy infrastructure in developing countries remains a significant financial, policy
and technological challenge. The growth of the electric vehicle (EV) industry will rapidly expand
the resource of partially degraded, ‘retired’, but still usable batteries in 2016 and beyond. These
batteries can become the storage hubs for community-scale grids in the developing world. We model
the resource and performance potential and the technological and economic aspects of the utilization
of retired EV batteries in rural and decentralized mini- and micro-grids. We develop and explore
four economic scenarios across three battery chemistries to examine the impacts on transport and
recycling logistics. We find that EVs sold through 2020 will produce 120–549 GWh in retired storage
potential by 2028. Outlining two use scenarios for decentralized systems, we discuss the possible
impacts on global electrification rates. We find that used EV batteries can provide a cost-effective
and...

http://iopscience.iop.org/1748-9326/9/9/094004 2014/09/23 - 21:24

Subsurface fluid-pressure declines caused by pumping of groundwater or hydrocarbons can lead to
aquifer-system compaction and consequent land subsidence. This subsidence can be rapid, as much as
30 cm per year in some instances, and large, totaling more than 13 m in extreme examples. Thus
anthropogenic subsidence may be the dominant contributor to relative sea-level rise in coastal
environments where subsurface fluids are heavily exploited. Maximum observed rates of human-induced
subsidence greatly exceed the rates of natural subsidence of unconsolidated sediments (∼0.1–1 cm yr
−1 ) and the estimated rates of ongoing global sea-level rise (∼0.3 cm yr −1 ).

http://iopscience.iop.org/1748-9326/9/9/091002 2014/09/23 - 21:24

The tropical seascape provides food and livelihoods to hundreds of millions of people, but the
support of key habitats to this supply remains ill appreciated. For fisheries and conservation
management actions to help promote resilient ecosystems, sustainable livelihoods, and food supply,
knowledge is required about the habitats that help support fisheries productivity and the
consequences of this for food security. This paper provides an interdisciplinary case study from the
coral triangle of how seagrass meadows provide support for fisheries and local food security. We
apply a triangulated approach that utilizes ecological, fisheries and market data combined with over
250 household interviews. Our research demonstrates that seagrass associated fauna in a coral
triangle marine protected area support local food supply contributing at least 50% of the fish based
food. This formed between 54% and 99% of daily protein intake in the area. Fishery catch was found
to significantly vary ...

http://iopscience.iop.org/1748-9326/9/9/094005 2014/09/23 - 21:24

We know from land, energy and climate studies that the livestock sector plays a substantial role in
deforestation, biodiversity loss and climate change. More recently it has become clear that
livestock also significantly contributes to humanity’s water footprint, water pollution and water
scarcity. Jalava et al ( Environ. Res . Lett . 9 [http://dx.doi.org/10.1088/1748-9326/9/7/074016]
074016 ) show that considerable water savings can be achieved by reducing the fraction of animal
products in our diet. The findings are in line with a few earlier studies on water use in relation
to diets. As yet, this insight has not been taken forward in national water policies, which focus on
‘sustainable production’ rather than ‘sustainable consumption’. Most studies and practical efforts
focus on increasing water-use efficiency in crop production (more crop per drop) and feed conversion
efficiency in the livestock sector (more meat with less feed). Water-use ...

http://iopscience.iop.org/1748-9326/9/9/091003 2014/09/23 - 21:24

Net primary production (NPP) is the principal source of energy for ecosystems and, by extension,
human populations that depend on them. The relationship between the supply and demand of NPP is
important for the assessment of socio-ecological vulnerability. We present an analysis of the supply
and demand of NPP in the Sahel using NPP estimates from the MODIS sensor and agri-environmental data
from FAOSTAT. This synergistic approach allows for a spatially explicit estimation of human impact
on ecosystems. We estimated the annual amount of NPP required to derive food, fuel and feed between
2000 and 2010 for 22 countries in sub-Saharan Africa. When comparing annual estimates of supply and
demand of NPP, we found that demand increased from 0.44 PgC to 1.13 PgC, representing 19% and 41%,
respectively, of available supply due to a 31% increase in the human population between 2000 and
2010. The demand for NPP has been increasing at an annual rate of 2.2% but NPP supply was
near-constant ...

http://iopscience.iop.org/1748-9326/9/9/094003 2014/09/11 - 22:50

In January 2013, a severe regional haze occurred over the North China Plain. An online-coupled
meteorology-chemistry model was employed to simulate the impacts of aerosol–meteorology interactions
on fine particles (PM 2.5 ) pollution during this haze episode. The response of PM 2.5 to
meteorology change constituted a feedback loop whereby planetary boundary layer (PBL) dynamics
amplified the initial perturbation of PM 2.5 . High PM 2.5 concentrations caused a decrease of
surface solar radiation. The maximal decrease in daily average solar radiation reached 53% in
Beijing, thereby leading to a more stable PBL. The peak PBL height in Beijing decreased from 690 m
to 590 m when the aerosol extinction was considered. Enhanced PBL stability suppressed the
dispersion of air pollutants, and resulted in higher PM 2.5 concentrations. The maximal increase of
PM 2.5 concentrations reached 140 μ g m −3 in Beijing. Durin...

http://iopscience.iop.org/1748-9326/9/9/094002 2014/09/11 - 22:50

Understanding the reliability and uncertainty associated with water supply yields derived from
surface water reservoirs is central for planning purposes. Using a global dataset of monthly river
discharge, we introduce a generalized model for estimating the mean and variance of water supply
yield, Y , expected from a reservoir for a prespecified reliability, R , and storage capacity, S
assuming a flow record of length n . The generalized storage–reliability–yield (SRY) relationships
reported here have numerous water resource applications ranging from preliminary water supply
investigations, to economic and climate change impact assessments. An example indicates how our
generalized SRY relationship can be combined with a hydroclimatic model to determine the impact of
climate change on surface reservoir water supply yields. We also document that the variability of
estimates of water supply yield are invariant to characteristics of the reservoir system, inclu...

http://iopscience.iop.org/1748-9326/9/9/095006 2014/09/11 - 22:50

According to the 2007 IPCC report, the alpine tundra ecosystems found on low mountains of the
northern hemisphere are amongst the most threatened by climate change. A treeline advance or a
significant erect shrub expansion could result in increased competition for the arctic-alpine
species usually found on mountaintops and eventually lead to their local extinction. The objectives
of our study were to identify recent changes in the cover and growth of erect woody vegetation in
the alpine tundra of Mont de la Passe, in the Parc National de la Gaspésie (Québec, Canada). The
comparison of two orthorectified aerial photos revealed no significant shift of the treeline between
1975 and 2004. During the same period however, shrub species cover increased from 20.2% to 30.4% in
the lower alpine zone. Dendrochronological analyses conducted on Betula glandulosa Michx. sampled at
three different positions along an altitudinal gradient (low, intermediate and high alpine zone)
revealed t...

http://iopscience.iop.org/1748-9326/9/9/094001 2014/09/11 - 22:50

We studied long-term fluctuations of streamflow and occurrence of extreme phenomena on the rivers of
Belarus during the post-World War II period. It was found that formation of annual runoff within the
nation has no constant tendencies and varies from year to year. At the same time, analysis of
intra-annual distribution of streamflow reveals significant changes since the 1970s, first of all,
increase of winter and decrease of spring streamflow. As a result, the frequency of extreme floods
has decreased. These changes in water regime are associated with climatic anomalies (increase of the
surface air temperatures) caused by large-scale alterations in atmospheric circulation, specifically
in trajectories of cyclones. During the last two decades, the frequency of Atlantic and southern
cyclones has changed and caused decreasing of cold season storms and extreme phenomena on the
rivers.

http://iopscience.iop.org/1748-9326/9/9/095005 2014/09/11 - 22:50

Plastic film mulching has played an important role in Chinese agriculture due to its soil warming
and moisture conservation effects. With the help of plastic film mulch technology, grain and cash
crop yields have increased by 20–35% and 20–60%, respectively. The area of plastic film coverage in
China reached approximately 20 million hectares, and the amount of plastic film used reached 1.25
million tons in 2011. While producing huge benefits, plastic film mulch technology has also brought
on a series of pollution hazards. Large amounts of residual plastic film have detrimental effects on
soil structure, water and nutrient transport and crop growth, thereby disrupting the agricultural
environment and reducing crop production. To control pollution, the Chinese government urgently
needs to elevate plastic film standards. Meanwhile, research and development of biodegradable mulch
film and multi-functional mulch recovery machinery will help promote effective control and
management of ...

http://iopscience.iop.org/1748-9326/9/9/091001 2014/09/11 - 22:50

The United States (US) is among the global hotspots of nitrogen (N) deposition and assessing the
temporal trends of wet N deposition is relevant to quantify the effectiveness of existing N
regulation policies and its consequent environmental effects. This study analyzed changes in
observed wet deposition of dissolved inorganic N (DIN = ammonium + nitrate) in the US between 1985
and 2012 by applying a Mann–Kendall test and Regional Kendall test. Current wet DIN deposition
(2011–2012) data were used to gain insight in the current pattern of N deposition. Wet DIN
deposition generally decreased going from Midwest > Northeast > South > West region with a national
mean rate of 3.5 kg N ha −1 yr −1 . Ammonium dominated wet DIN deposition in the Midwest, South and
West regions, whereas nitrate and ammonium both contributed a half in the Northeast region. Wet DIN
deposition showed no significant change at the national scale between 1985 and 2012, but profound
c...

http://iopscience.iop.org/1748-9326/9/9/095004 2014/09/09 - 09:28

China is the world’s largest consumer of synthetic nitrogen (N), where very low rates of fertilizer
N recovery in crops have been reported, raising discussion around whether fertilizer N use can be
significantly reduced without yield penalties. However, using recovery rates as indicator ignores a
possible residual effect of fertilizer N—a factor often unknown at large scales. Such residual
effect might store N in the soil increasing N availability for subsequent crops. The objectives of
the present study were therefore to quantify the residual effect of fertilizer N in China and to
obtain more realistic rates of the accumulative fertilizer N recovery efficiency (RE) in crop
production systems of China. Long-term spatially-extensive data on crop production, fertilizer N and
other N inputs to croplands in China were used to analyze the relationship between crop N uptake and
fertilizer N input (or total N input), and to estimate the amount of residual fertilizer N.
Measurement resul...

http://iopscience.iop.org/1748-9326/9/9/095002 2014/09/09 - 09:28

The United Kingdom currently reports nitrous oxide emissions from agriculture using the IPCC default
Tier 1 methodology. However Tier 1 estimates have a large degree of uncertainty as they do not
account for spatial variations in emissions. Therefore biogeochemical models such as DailyDayCent
(DDC) are increasingly being used to provide a spatially disaggregated assessment of annual
emissions. Prior to use, an assessment of the ability of the model to predict annual emissions
should be undertaken, coupled with an analysis of how model inputs influence model outputs, and
whether the modelled estimates are more robust that those derived from the Tier 1 methodology. The
aims of the study were (a) to evaluate if the DailyDayCent model can accurately estimate annual N 2
O emissions across nine different experimental sites, (b) to examine its sensitivity to different
soil and climate inputs across a number of experimental sites and (c) to examine the influence of
uncertainty i...

http://iopscience.iop.org/1748-9326/9/9/095003 2014/09/09 - 09:28

In Denmark, drinking water quality data covering the entire country for over 35 years are registered
in a publicly-accessible database. These data were analysed to determine the fraction of population
exposed to elevated nitrate concentrations. Data from 2,852 water supply areas from the 98 Danish
municipalities were collected in one dataset. Public water supplies are extensively registered;
private wells supplying only few households are neither monitored nor registered sufficiently. The
study showed that 5.1% of the Danish population was exposed to nitrate concentrations ##IMG##
[http://ej.iop.org/images/1748-9326/9/9/095001/erl498377ieqn1.gif] {$\gt $} 25 mg L −1 in 2012.
Private well users were far more prone to exposure to elevated nitrate concentrations than consumers
connected to public supplies. While the fraction exposed to elevated nitrate concentrations amongst
public supply users has been decreasing since the 1970s, it has been increasi...

http://iopscience.iop.org/1748-9326/9/9/095001 2014/09/09 - 09:28

Solutions to meet growing food requirements in a world of limited suitable land and degrading
environment focus mainly on increasing crop yields, particularly in poorly performing regions, and
reducing animal product consumption. Increasing yields could alleviate land requirements, but
imposing higher soil nutrient withdrawals and in most cases larger fertilizer inputs. Lowering
animal product consumption favors a more efficient use of land as well as soil and fertilizer
nutrients; yet actual saving may largely depend on which crops and how much fertilizer are used to
feed livestock versus people. We show, with a global analysis, how the choice of cultivated plant
species used to feed people and livestock influences global food production as well as soil nutrient
withdrawals and fertilizer additions. The 3 to 15-fold differences in soil nutrient withdrawals per
unit of energy or protein produced that we report across major crops explain how composition shifts
over the last 20 yea...

http://iopscience.iop.org/1748-9326/9/8/084014 2014/08/30 - 06:52

Worldwide, lack of data on stream temperature has motivated the use of regression-based statistical
models to predict stream temperatures based on more widely available data on air temperatures. Such
models have been widely applied to project responses of stream temperatures under climate change,
but the performance of these models has not been fully evaluated. To address this knowledge gap, we
examined the performance of two widely used linear and nonlinear regression models that predict
stream temperatures based on air temperatures. We evaluated model performance and temporal stability
of model parameters in a suite of regulated and unregulated streams with 11–44 years of stream
temperature data. Although such models may have validity when predicting stream temperatures within
the span of time that corresponds to the data used to develop them, model predictions did not
transfer well to other time periods. Validation of model predictions of most recent stream
temperatures, based...

http://iopscience.iop.org/1748-9326/9/8/084015 2014/08/30 - 06:52

The impact of projected Arctic sea ice loss on the stratosphere is investigated using the Whole
Atmosphere Community Climate Model (WACCM), a state-of-the-art coupled chemistry climate model. Two
91-year simulations are conducted: one with a repeating seasonal cycle of Arctic sea ice for the
late twentieth-century, taken from the fully coupled WACCM historical run; the other with Arctic sea
ice for the late twenty-first century, obtained from the fully coupled WACCM RCP8.5 run. In response
to Arctic sea ice loss, polar cap stratospheric ozone decreases by 13 DU (34 DU at the North Pole)
in spring, confirming the results of Scinocca et al (2009 Geophys. Res. Lett. 36
[http://dx.doi.org/10.1029/2009gl041239] L24701 ). The ozone loss is dynamically initiated in March
by a suppression of upward-propagating planetary waves, possibly related to the destructive
interference between the forced wave number 1 and its climatology. The diminished upward wave...

http://iopscience.iop.org/1748-9326/9/8/084016 2014/08/30 - 06:52

This study examines the effect of the bacterial species Pseudomonas syringae acting as ice nuclei
(IN) on cloud properties to understand its impact on local radiative budget and heating rates. These
bacteria may become active IN at temperatures as warm as −2 °C. Numerical simulations were developed
using the Brazilian Regional Atmospheric Model System (BRAMS). To investigate the isolated effect of
bacterial IN, four scenarios were created considering only homogeneous and bacterial ice nucleation,
with 1, 10 and 100 IN per cubic meter of cloud volume and one with no bacteria. Moreover, two other
scenarios were generated: the BRAMS default parameterization and its combination with bacterial IN.
The model reproduced a strong convective cell over São Paulo on 3 March 2003. Results showed that
bacterial IN may change cloud evolution as well as its microphysical properties, which in turn
influence cloud radiative properties. For example, the reflected shortwave irradiance over a...

http://iopscience.iop.org/1748-9326/9/8/084020 2014/08/30 - 06:52

Summer (June–July–August; JJA) UK precipitation extremes projections from two UK Met Office
high-resolution (12 km and 1.5 km) regional climate models (RCMs) are shown to be resolution
dependent. The 1.5 km RCM projects a uniform ( ##IMG##
[http://ej.iop.org/images/1748-9326/9/8/084019/erl499663ieqn1.gif] {$\approx 10\%$} ) increase in 1
h JJA precipitation intensities across a range of return periods. The 12 km RCM, in contrast,
projects decreases in short return period (≦̸5 years) events but strong increases in long return
period (⩾20 years) events. We have low physical and statistical confidence in the 12 km RCM
projections for longer return periods. Both models show evidence for longer dry periods between
events. In winter (December–January–February; DJF), the models show larger return level increases
(⩾40%). Both DJF projections are consistent with results from previous work based on coarser
resolution models.

http://iopscience.iop.org/1748-9326/9/8/084019 2014/08/30 - 06:52

Crop yields must increase substantially to meet the increasing demands for agricultural products.
Crop yield increases are particularly important for Russia because low crop yields prevail across
Russia’s widespread and fertile land resources. However, reliable data are lacking regarding the
spatial distribution of potential yields in Russia, which can be used to determine yield gaps. We
used a crop growth model to determine the yield potentials and yield gaps of winter and spring wheat
at the provincial level across European Russia. We modeled the annual yield potentials from 1995 to
2006 with optimal nitrogen supplies for both rainfed and irrigated conditions. Overall, the results
suggest yield gaps of 1.51–2.10 t ha −1 , or 44–52% of the yield potential under rainfed conditions.
Under irrigated conditions, yield gaps of 3.14–3.30 t ha −1 , or 62–63% of the yield potential, were
observed. However, recurring droughts cause large fluctuations in yield potentials...

http://iopscience.iop.org/1748-9326/9/8/084017 2014/08/30 - 06:52

Permafrost soils store over half of global soil carbon (C), and northern frozen peatlands store
about 10% of global permafrost C. With thaw, inundation of high latitude lowland peatlands typically
increases the surface-atmosphere flux of methane (CH 4 ), a potent greenhouse gas. To examine the
effects of lowland permafrost thaw over millennial timescales, we measured carbon dioxide (CO 2 )
and CH 4 exchange along sites that constitute a ∼1000 yr thaw chronosequence of thermokarst collapse
bogs and adjacent fen locations at Innoko Flats Wildlife Refuge in western Alaska. Peak CH 4
exchange in July (123 ± 71 mg CH 4 –C m −2 d −1 ) was observed in features that have been thawed for
30 to 70 (<100) yr, where soils were warmer than at more recently thawed sites (14 to 21 yr;
emitting 1.37 ± 0.67 mg CH 4 –C m −2 d −1 in July) and had shallower water tables than at older
sites (200 to 1400 ...

http://iopscience.iop.org/1748-9326/9/8/085004 2014/08/30 - 06:52