Scientist and Stakeholder Views on the Delta Ecosystem
... All ongoing processes advocate science as the basis of decisionmaking, but science itself has become a major source of conflict. Although scientific understanding of the ecosystem has vastly improved, the complexity of the Delta means that many uncertainties remain. Meanwhile, native fish population ...
... All ongoing processes advocate science as the basis of decisionmaking, but science itself has become a major source of conflict. Although scientific understanding of the ecosystem has vastly improved, the complexity of the Delta means that many uncertainties remain. Meanwhile, native fish population ...
绵羊口液对羊草(Leymus chinensis)再生生长的作用 及其生理机制
... structure and dynamics, linked to climatic conditions and environmental management Substrate for the detritus food web, nutrient reservoir, and contributor to mineral-nutrient cycling and energy flow Alter microenvironment and plant community ...
... structure and dynamics, linked to climatic conditions and environmental management Substrate for the detritus food web, nutrient reservoir, and contributor to mineral-nutrient cycling and energy flow Alter microenvironment and plant community ...
Disturbance and Diversity in Low-Productivity
... (Collins et al., 1998; Gough and Grace, 1998; Olff et al., 1999; Grime, 2001). Because resource availability limits population growth, the direction of the plant diversity response to herbivory is widely thought to depend on ecosystem productivity (Huston, 1994; Olff et al., 1999; Grime, 2001). Gene ...
... (Collins et al., 1998; Gough and Grace, 1998; Olff et al., 1999; Grime, 2001). Because resource availability limits population growth, the direction of the plant diversity response to herbivory is widely thought to depend on ecosystem productivity (Huston, 1994; Olff et al., 1999; Grime, 2001). Gene ...
Ecosystem Flips, Locks, and Feedbacks: the
... interactive species), its impacts extend well beyond those species and affect the entire ecosystem (Soulé et al. 2003). Here, we focus on the sea-urchin fishery and its impact on kelp forest ecosystems in the Gulf of Maine. Globally, plant-herbivore interactions between sea urchins and kelp forests ...
... interactive species), its impacts extend well beyond those species and affect the entire ecosystem (Soulé et al. 2003). Here, we focus on the sea-urchin fishery and its impact on kelp forest ecosystems in the Gulf of Maine. Globally, plant-herbivore interactions between sea urchins and kelp forests ...
Organic farming
... If these practices were to intensify in the future they could reduce the overall benefits for ground-nesting birds. Both organic and conventional farms will perform better when under agri-environmental schemes. Soil Quality Soil organic matter benefits many aspects of soil quality. This has long bee ...
... If these practices were to intensify in the future they could reduce the overall benefits for ground-nesting birds. Both organic and conventional farms will perform better when under agri-environmental schemes. Soil Quality Soil organic matter benefits many aspects of soil quality. This has long bee ...
biodiversity in drylands - Food and Agriculture Organization of the
... diversity they value most in domestic livestock and crops. 3.2- Status of Dryland Biodiversity Dryland ecosystems are unique. One can site such examples as the Mediterranean systems (e.g. the distinctive sclerophyllous vegetation of the Mediterranean Basin, drylands of Southern Australia and Califor ...
... diversity they value most in domestic livestock and crops. 3.2- Status of Dryland Biodiversity Dryland ecosystems are unique. One can site such examples as the Mediterranean systems (e.g. the distinctive sclerophyllous vegetation of the Mediterranean Basin, drylands of Southern Australia and Califor ...
LOCAL DISTURBANCE CYCLES AND THE MAINTENANCE OF
... Abstract. In marine systems, the occurrence and implications of disturbance–recovery cycles have been revealed at the landscape level, but only in demographically open or closed systems where landscape-level dynamics are assumed to have no feedback effect on regional dynamics. We present a mussel me ...
... Abstract. In marine systems, the occurrence and implications of disturbance–recovery cycles have been revealed at the landscape level, but only in demographically open or closed systems where landscape-level dynamics are assumed to have no feedback effect on regional dynamics. We present a mussel me ...
Questions for Chapter 55 – Dynamics of Ecosystems
... the case, is difficult to determine due to all of the complex factors that determine food chain length and structure. Moreover, there are many practical difficulties associated with measuring actual food chain length in natural systems. 2. Given that, in general, energy input is greatest at the bott ...
... the case, is difficult to determine due to all of the complex factors that determine food chain length and structure. Moreover, there are many practical difficulties associated with measuring actual food chain length in natural systems. 2. Given that, in general, energy input is greatest at the bott ...
fires, ecological effects of
... and ecosystem structure. Continuity of flammable vegetation, especially at the landscape scale, strongly influences the spread of fires. Habitat fragmentation can lead to a reduction in fire frequency of isolated fire-prone ecosystems or an increase in fire-excluding forests surrounded by flammable vegetat ...
... and ecosystem structure. Continuity of flammable vegetation, especially at the landscape scale, strongly influences the spread of fires. Habitat fragmentation can lead to a reduction in fire frequency of isolated fire-prone ecosystems or an increase in fire-excluding forests surrounded by flammable vegetat ...
World Conservation Strategy
... . Human beings, in their quest for economic development and enjoyment of the riches of nature, must come to terms with the reality of resource limitation· and the carrying capacities of ecosystems·, and must take acc~unt of the needs of future generations. This is the message of conservation. For if ...
... . Human beings, in their quest for economic development and enjoyment of the riches of nature, must come to terms with the reality of resource limitation· and the carrying capacities of ecosystems·, and must take acc~unt of the needs of future generations. This is the message of conservation. For if ...
Life in the Aftermath of Mass Extinctions
... complexity in ecosystems, the fundamental organization (structure) and function of ecosystems is often permanently changed (Figure 2B) [13,39–41]. How do we know that ecosystems changed, and what does it mean for understanding the evolution of life in the aftermath? The PT extinction, the greatest m ...
... complexity in ecosystems, the fundamental organization (structure) and function of ecosystems is often permanently changed (Figure 2B) [13,39–41]. How do we know that ecosystems changed, and what does it mean for understanding the evolution of life in the aftermath? The PT extinction, the greatest m ...
Israel`s Fifth National Report to the United Nations Convention on
... density had increased, and in 7% of them it had decreased, in part due to fires and in part due to a long drought in the Mediterranean part of the country. Specific monitoring of various endangered species shows mixed trends. As for threats, it was found that habitat loss and fragmentation continues ...
... density had increased, and in 7% of them it had decreased, in part due to fires and in part due to a long drought in the Mediterranean part of the country. Specific monitoring of various endangered species shows mixed trends. As for threats, it was found that habitat loss and fragmentation continues ...
The Ecosystem Role of Fishes in Lotic Environments
... migrant fertilization impacts were relatively limited. In contrast, migrants had more substantial negative effects on periphyton chlorophyll-a due to spawning activity. In general, field results agreed with results from the meta-analysis. Fishes in streams tended to have positive effects on nutrient ...
... migrant fertilization impacts were relatively limited. In contrast, migrants had more substantial negative effects on periphyton chlorophyll-a due to spawning activity. In general, field results agreed with results from the meta-analysis. Fishes in streams tended to have positive effects on nutrient ...
Part 3 Designing and Implementing Ecosystem Connectivity in the
... [3]. Successful pollination depends on maintaining a variety of pollinators, including native pollinators. For example, the Mason Bee is 5 to 10 times more efficient at pollination than are domestic honey bees. Unfortunately both species are declining. Scientists believe that habitat loss and altera ...
... [3]. Successful pollination depends on maintaining a variety of pollinators, including native pollinators. For example, the Mason Bee is 5 to 10 times more efficient at pollination than are domestic honey bees. Unfortunately both species are declining. Scientists believe that habitat loss and altera ...
Great Barrier Reef Outlook Report 2014—In Brief
... Great Barrier Reef. They are important in the life cycle of some marine species and also play a role in slowing overland water flow and trapping sediments and nutrients. While not on the same scale as historic broadscale clearing, without active planning and management, incremental modification of t ...
... Great Barrier Reef. They are important in the life cycle of some marine species and also play a role in slowing overland water flow and trapping sediments and nutrients. While not on the same scale as historic broadscale clearing, without active planning and management, incremental modification of t ...
Rare Plant Communities and Plant Species Report
... Red- and Blue-Listed Plant Communities of the Bulkley The order of presentation follows the CDC tracking list of June 10, 1996 (Table 2). Please refer to the Field Guide to Site Identification and Interpretation for the Prince Rupert Forest Region (Banner et al. 1993) for a more complete description ...
... Red- and Blue-Listed Plant Communities of the Bulkley The order of presentation follows the CDC tracking list of June 10, 1996 (Table 2). Please refer to the Field Guide to Site Identification and Interpretation for the Prince Rupert Forest Region (Banner et al. 1993) for a more complete description ...
How body size mediates the role of animals in nutrient cycling in
... size in controlling the degree to which animals contribute to ecosystem nutrient fluxes. Body size may control animal-mediated nutrient cycling by three main mechanisms. First, small animals have higher metabolism and, therefore, higher mass-specific excretion rates (Wen & Peters, 1994; Brown, Allen ...
... size in controlling the degree to which animals contribute to ecosystem nutrient fluxes. Body size may control animal-mediated nutrient cycling by three main mechanisms. First, small animals have higher metabolism and, therefore, higher mass-specific excretion rates (Wen & Peters, 1994; Brown, Allen ...
Bottom-Up and Top-Down Interactions across Aquatic
... rhythms set the stage for the degree of exposure to potentially stressful atmospheric conditions (e.g., intense light, high or low temperatures, wind, rain, ice), especially for those organisms living higher on the shore. Even organisms living in tidal pools experience a wider range of physical cond ...
... rhythms set the stage for the degree of exposure to potentially stressful atmospheric conditions (e.g., intense light, high or low temperatures, wind, rain, ice), especially for those organisms living higher on the shore. Even organisms living in tidal pools experience a wider range of physical cond ...
[FSH] 1909.12 - USDA Forest Service
... parties, and the public to provide existing information for the assessment. The planning requirement at 36 CFR 219.6(b) describes the content of the assessment for plan development and plan revision. (b) Content of the assessment for plan development or revision. In the assessment for plan developme ...
... parties, and the public to provide existing information for the assessment. The planning requirement at 36 CFR 219.6(b) describes the content of the assessment for plan development and plan revision. (b) Content of the assessment for plan development or revision. In the assessment for plan developme ...
Pausch J., Kramer S., Scharroba A., Scheunemann N
... studies using stable isotopes targeted at elucidating trophic interactions in agro-ecosystems, and no quantitative fluxes within food web compartments are at hand (Traugott et al. 2013). In this study, we quantified the incorporation of rootderived C into the soil food web of an arable field and compil ...
... studies using stable isotopes targeted at elucidating trophic interactions in agro-ecosystems, and no quantitative fluxes within food web compartments are at hand (Traugott et al. 2013). In this study, we quantified the incorporation of rootderived C into the soil food web of an arable field and compil ...
pdf reprint
... be applicable, as the same theory could be used to predict that many small fragments of contrasting habitats may conserve more species than do large fragments (Simberloff and Abele 1976). Still, it came as a surprise that results were inconsistent and in some cases divergent (Debinski and Holt 2000) ...
... be applicable, as the same theory could be used to predict that many small fragments of contrasting habitats may conserve more species than do large fragments (Simberloff and Abele 1976). Still, it came as a surprise that results were inconsistent and in some cases divergent (Debinski and Holt 2000) ...
DRAFT URBAN ECOLOGY AND BIODIVERSITY STRATEGY The
... Healthy ecosystems and rich biodiversity are vital for the liveability and wellbeing of our city. Protecting and enhancing biodiversity will support the health and wellbeing of our community and contribute to effective climate change adaptation actions. The City of Melbourne has developed this strat ...
... Healthy ecosystems and rich biodiversity are vital for the liveability and wellbeing of our city. Protecting and enhancing biodiversity will support the health and wellbeing of our community and contribute to effective climate change adaptation actions. The City of Melbourne has developed this strat ...
Effects of plant diversity, N fertilization, and elevated
... respect to nitrate as compared with diverse communities. Predictions such as these are infrequently tested because their evaluation requires long-term records of multiple components of the terrestrial N cycle. To test these predictions and to explore dynamics in the effects of elevated CO2, N fertil ...
... respect to nitrate as compared with diverse communities. Predictions such as these are infrequently tested because their evaluation requires long-term records of multiple components of the terrestrial N cycle. To test these predictions and to explore dynamics in the effects of elevated CO2, N fertil ...
Ecosystem
An ecosystem is a community of living organisms in conjunction with the nonliving components of their environment (things like air, water and mineral soil), interacting as a system. These biotic and abiotic components are regarded as linked together through nutrient cycles and energy flows. As ecosystems are defined by the network of interactions among organisms, and between organisms and their environment, they can be of any size but usually encompass specific, limited spaces (although some scientists say that the entire planet is an ecosystem).Energy, water, nitrogen and soil minerals are other essential abiotic components of an ecosystem. The energy that flows through ecosystems is obtained primarily from the sun. It generally enters the system through photosynthesis, a process that also captures carbon from the atmosphere. By feeding on plants and on one another, animals play an important role in the movement of matter and energy through the system. They also influence the quantity of plant and microbial biomass present. By breaking down dead organic matter, decomposers release carbon back to the atmosphere and facilitate nutrient cycling by converting nutrients stored in dead biomass back to a form that can be readily used by plants and other microbes.Ecosystems are controlled both by external and internal factors. External factors such as climate, the parent material which forms the soil and topography, control the overall structure of an ecosystem and the way things work within it, but are not themselves influenced by the ecosystem. Other external factors include time and potential biota. Ecosystems are dynamic entities—invariably, they are subject to periodic disturbances and are in the process of recovering from some past disturbance. Ecosystems in similar environments that are located in different parts of the world can have very different characteristics simply because they contain different species. The introduction of non-native species can cause substantial shifts in ecosystem function. Internal factors not only control ecosystem processes but are also controlled by them and are often subject to feedback loops. While the resource inputs are generally controlled by external processes like climate and parent material, the availability of these resources within the ecosystem is controlled by internal factors like decomposition, root competition or shading. Other internal factors include disturbance, succession and the types of species present. Although humans exist and operate within ecosystems, their cumulative effects are large enough to influence external factors like climate.Biodiversity affects ecosystem function, as do the processes of disturbance and succession. Ecosystems provide a variety of goods and services upon which people depend; the principles of ecosystem management suggest that rather than managing individual species, natural resources should be managed at the level of the ecosystem itself. Classifying ecosystems into ecologically homogeneous units is an important step towards effective ecosystem management, but there is no single, agreed-upon way to do this.