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Grasslands - UC Davis Plant Sciences
Grasslands - UC Davis Plant Sciences

... influence the effects of annual variations in weather and affect how weather variations influence interactions among vegetation composition, other organisms (e.g., small mammals, large herbivores, microbes, insects), disturbance regimes, and human management. These interactions AQ: Source or determi ...
fires, ecological effects of
fires, ecological effects of

... shrublands and require fire to release seeds from serotinous cones or to stimulate germination. Among trees in fire-prone forests, many conifers do not sprout and a few eucalypts are also killed by fire. Nonsprouting species are particularly prone to local extinction if recruitment fails after burning. ...
Tentative List with Brief Descriptions
Tentative List with Brief Descriptions

... distinguish form other agricultural landscapes because of the unusually high plant species richness both on the ecosystem and micro-community level. For that reason they have been of great interest to many scientists. These communities are habitats for many rare and endangered species. Opposite to m ...
Introduction
Introduction

... of degraded karst ecosystems. Karst restoration has become the core issue in research related to environmental changes in karst areas. With the implementation of the World Heritage List and Rocky Desertification Project in recent years, the number of related research papers has shown rapid growth an ...
Direct and Indirect Ecosystem Effects of Evolutionary
Direct and Indirect Ecosystem Effects of Evolutionary

... adaptations to these divergent predation regimes (Reznick 1982). Guppies from HP communities mature at a younger age and a smaller size than their LP counterparts (Reznick 1982; Reznick and Endler 1982). HP guppies also have more, smaller offspring than LP fish and overall invest more resources in r ...
What is a Trophic Cascade? - College of Forestry
What is a Trophic Cascade? - College of Forestry

... Strong concluded that ‘true’ trophic cascades were less prevalent in the terrestrial realm [15]. As a result, there was an almost exclusive research focus on freshwater systems during the early 1990s (Figure 1). Trophic cascades were thought to be less important in terrestrial communities because th ...
Another soil slide show - OH Anderson Elementary
Another soil slide show - OH Anderson Elementary

... thinner A horizons and B horizons that have been enriched in many elements because of leaching. ...
Here
Here

... thinner A horizons and B horizons that have been enriched in many elements because of leaching. ...
weathering
weathering

... thinner A horizons and B horizons that have been enriched in many elements because of leaching. ...
Dividing up the pie: Whales, fish, and humans as competitors
Dividing up the pie: Whales, fish, and humans as competitors

... ‘‘mild’’ vs. ‘‘severe’’ response. Both analysis techniques allowed us to address two sources of uncertainty and quantify confidence in scenario results: (1) uncertainty among physiological rate, diet, and predator–prey functional response parameters; and (2) potential compensatory changes to communit ...
First results from an experiment excluding three sizes classes of
First results from an experiment excluding three sizes classes of

... large) on nine functional groups of plants in the low arctic tundra of the Yamal Peninsula (Russia). Herbivore faeces counts in the exclosures and pictures from automatic cameras proved that the experimental setup worked. The majority of plant groups did not respond to exclusion of herbivores, suppo ...
The SER Primer on Ecological Restoration
The SER Primer on Ecological Restoration

... groups. The physical or abiotic environment that sustains the biota of an ecosystem includes the soil or substrate, the atmospheric or aqueous medium, hydrology, weather and climate, topographic relief and aspect, the nutrient regime, and the salinity regime. Habitat refers to the dwelling place of ...
The Pleasures of Soil Watching - Soil Science at UW
The Pleasures of Soil Watching - Soil Science at UW

... carefree exploration of the world of soil to discuss a life and death matter. For hundreds of millions of years, life forms, human beings among them, have evolved in a rich and proportioned environment of elements and compounds. The adequacy of that milieu is increasingly threatened in two ways (as ...
Year12 2007 Exam & Marking notes
Year12 2007 Exam & Marking notes

... and its consequences. Weaker responses listed the issues (such as bioaccumulation and biomagnification in food chains/webs) and provided arguments for and/or against them. They used specific examples of pesticides to argue the issues, including the impact on non-target species. However, they gave mi ...
Vegetation Change and Ecosystem Services
Vegetation Change and Ecosystem Services

... not been well defined beyond the classifications of Valley Grasslands and Coastal Prairie. Soft chess brome (Bromus hordeaceus) and broadleaf filaree (Erodium botrys) are common in areas with 65-100 cm (25-40 in) of rainfall, and red brome (B. madratensis) and redstem filaree (E. cicutarium) are com ...
Fungal alteration of the elemental composition of leaf litter affects
Fungal alteration of the elemental composition of leaf litter affects

... used for determination of DM, ground and used for determinations of phosphorus (P), N and C concentrations. Four microcosms (i.e. two microcosms per thickness level) were kept sterile and were used as controls for abiotic decomposition. Mass loss and leaf physical–chemical characteristics. Specific ...
Steady state solutions of an ecosystem mod
Steady state solutions of an ecosystem mod

... 6) for phytoplankton invasion, neither phytoplankton nor zooplankton will be present, and S = T. In the range Smin,O< T < Smin,O+ PO* (Eq. 6 and 7), the steady state value of S is pinned at Smin,O,and phytoplankton concentration PO steadily rises as T - Smin,O.In this range, the phytoplankton concen ...
Short-term changes of protozoan control on autotrophic
Short-term changes of protozoan control on autotrophic

... for 10 min for each sample in a liquid scintillation counter (Beckman'" LS 6000 IC). The number of newly produced bacterial cells was estimated from thymidine uptake using a conversion factor of 2 x 10'" cells mol"' thymidine (Bell, 1990). Protozoan abundance, biomass and grazing experiments To quan ...
Plant Diversity Surpasses Plant Functional Groups and Plant
Plant Diversity Surpasses Plant Functional Groups and Plant

... in many ecosystems. Knowledge of the consequences of biodiversity loss in terrestrial ecosystems is largely restricted to single ecosystem functions. Impacts of key plant functional groups on soil biota are considered to be more important than those of plant diversity; however, current knowledge mai ...
Guide Kjeldahl
Guide Kjeldahl

... flame tests to the atomic force microscope sent to Mars for the exploration of martian soil. At the time when Johan Kjeldahl published his method for the determination of nitrogen in 1883 the electric lamp was just patented and the technical age in its childhood. Seldom in human history has an inven ...
0231 EN
0231 EN

... Different Community policies contribute to soil protection, particularly environment (e.g. air and water) and agricultural (agri-environment and cross-compliance) policy. Agriculture can have positive effects on the state of soil. For instance, land management practices such as organic and integrate ...
Ecosystem change and stability over multiple decades in the
Ecosystem change and stability over multiple decades in the

... such as carbon capture and release). Although changes in Arctic ecosystems have been documented [4–11], attribution to a particular driver remains uncertain in some cases [12,13]. This is because of the multiple co-occurring drivers and also because any one driver such as climate warming can act on ...
The effects of chronic moderate noise on animal behavior and
The effects of chronic moderate noise on animal behavior and

... yet research on other stressors indicates that acclimation to a stressor might not release an organism from costs to fitness. Additionally, we have shown how behavioral modifications among individuals confronted with noise – even those individuals that outwardly appear to habituate – can lead to dec ...
current research, monitoring, and education
current research, monitoring, and education

... Since 1969, Baruch Institute research associates have completed more than 710 scientific research projects at the Baruch Marine Field Laboratory (BMFL), and students have completed hundreds of theses, dissertations, and special research projects. All of this work as well as projects conducted in oth ...
PowerPoint Presentation - No Slide Title
PowerPoint Presentation - No Slide Title

... • Fertilizers, which people use to stimulate and maximize plant growth, contain both nitrogen and phosphorus. • Excessive amounts of fertilizer can enter terrestrial and aquatic ecosystems through runoff. • Excess nitrogen and phosphorus can cause rapid growth of algae. • Excess algae can deplete an ...
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Human impact on the nitrogen cycle



Human impact on the nitrogen cycle is diverse. Agricultural and industrial nitrogen (N) inputs to the environment currently exceed inputs from natural N fixation. As a consequence of anthropogenic inputs, the global nitrogen cycle (Fig. 1) has been significantly altered over the past century. Global atmospheric nitrous oxide (N2O) mole fractions have increased from a pre-industrial value of ~270 nmol/mol to ~319 nmol/mol in 2005. Human activities account for over one-third of N2O emissions, most of which are due to the agricultural sector. This article is intended to give a brief review of the history of anthropogenic N inputs, and reported impacts of nitrogen inputs on selected terrestrial and aquatic ecosystems.
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