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GEOS536 FINAL

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Applied Ecology
1. What is applied ecology? How is it different from the general field of ecology? (10
points)
Applied ecology is concerned with organisms of practical importance and attempts to use
the theoretical insights and empirical concerns of academic ecology to solve specific problems
of environmental management (Slobodkin, 337). Applied ecology attempts to apply knowledge
of ecosystems and interactions between those systems and organisms to bring systems back
into balance to offset the impacts of human beings. Applied ecology is different from the
general field of ecology because the latter is focused on more than creating solutions for
specific problems of environmental management. The general field of ecology is also focused
on interactions between life and the physical environment, for example studying how
organisms affect material fluxes in nature. The sequestration of carbon dioxide by a forest
would be one example of this. Ecology could be defined as the scientific study of the
distribution and abundance of organisms, the interactions that determine that distribution and
abundance, and the relationships between organisms and the transformation and flux of
energy and matter.
Restoration Ecology
2. Some restoration ecologists have said that we must accept that full restoration (back to
some historic reference condition) of some ecosystems is impossible, and it would be
wiser to restore them to a novel state. What do you think of this statement? Is this a
practical recognition of an unfortunate reality, or an abandonment of the principles of
restoration ecology? Support your answer with examples and citations (45 points)
I agree with those restoration ecologists who have said that we must accept that complete
restoration (back to some historic reference condition) of some ecosystems is impossible. It
would be wiser to restore them to a novel state. Restoration to a novel state is a practical
recognition of an unfortunate reality in the field of restoration ecology as climate change
continues to threaten ecosystems as we know them. The focus of restoration ecology, and the
closely allied practice of ecological restoration, is the structure, composition, and functioning of
ecosystems in a given landscape (Van de Koppel, Johan, et al., 60). The authors mention that
when restoring ecosystems to their natural state, it is critical to consider that the spatial
structure of the original systems was self-organized, which ultimately has implications for the
functioning and resilience of these ecosystems (Van de Koppel, Johan, et al., 63). Any
restoration attempts that do not take into account this original spatial structure will likely lead
to a community or ecosystem that is more vulnerable to disturbances, supports lower
population sizes, and is possibly less species-rich than the pre-disturbance ecosystem (Van de
Koppel, Johan, et al., 63).
The authors go onto mention that the dynamics of communities are not determined by
interactions between a few species alone but rather by food webs, where nearly all organisms
are embedded in networks of interactions with other organisms consisting of literally thousands
of species (Van de Koppel, Johan, et al., 70). The authors suggest that ecologists who aim to reestablish ’a characteristic assemblages of the species that occur in the reference ecosystem’
should consider both the negatives and positives of interactions between and among species
within the network of community and trophic cascades which most likely differ between the
reference sites and the restored ecosystems (Van de Koppel, Johan, et al., 71).
They note that one of the most essential criteria for ecosystem restoration, articulated by
the SER Primer, is that restored ecosystems should be ‘resilient’. That resilience is an emergent
characteristic or attribute of an ecosystem’s ability to return to a previous steady state after
significant disturbances. Thus, the more resilient an ecosystem (or restored ecosystem) is, the
quicker it will be able to return to the previous steady-state (Van de Koppel, Johan, et al., 72).
They also acknowledge that there is a difference between resilience in ecological systems and
engineering systems. Resilience in ecological systems (‘ecological resilience’) is defined as the
ability to return to the previous equilibrium or as the magnitude of degradation that can be
absorbed before the ecosystem redefines its structure and develops towards a new equilibrium
(Van de Koppel, Johan, et al., 72). However, once a system surpasses that threshold of
irreversibility, it is disturbed and will shift to an alternative steady state. Resilience in
engineering systems (‘engineering resilience’) is defined as returning time to a previous state of
relative equilibrium. Only in the latter case can different ‘degrees of ecosystem resilience’ be
distinguished (Van de Koppel, Johan, et al., 72).
Along with the complexity of restoring an ecosystem to a historic reference condition
considering factors such as interactions between and among species within a biotic community,
which affect community structure and whole ecosystem functioning and environmental change,
ecologists face many other obstacles when embarking on such an endeavor. These obstacles
include but are not limited to lack of funding (restoration can be very costly), a changing
climate, increasing homogeneity, threats from invasive species, and changes in biogeochemical
processes due to human domination of earth’s ecosystems. One paper mentions current rates
of extinction are 100–1000 times greater than in pre-human times (IUCN 2007). These elevated
rates are being driven primarily by the conversion and degradation of native ecosystems by
human activities (McAlpine, Clive, et al., 37). They cite one major problem as a lack of
consensus between the ways plant and animal ecologists approach issues in restoration theory
and practice (McAlpine, Clive, et al., 38). Often in plant-based restoration, the goal is to return
the ecosystem to a historical state or ecological trajectory similar to that which existed before
the ecosystem was severely modified by human land use (McAlpine, Clive, et al., 38). This goal
may be unachievable given the degree of vegetation modification in the given area, which is
especially true if there are irreversible abiotic changes to nutrient levels and soil conditions or if
invasive exotic species have become established (McAlpine, Clive, et al., 38).
Plant and animal restoration differs in terms of goals of restoration. Plant restoration
focuses on measurable ecological objectives such as native plant species and functional
diversity. In contrast, animal restoration usually emphasizes individual species and their habitat
needs instead of community structure and composition (McAlpine, Clive, et al., 38). Depending
on which is the main focus of the restoration, the strategies and approaches to achieve their
goals will differ considerably. An ecologist must consider that their approaches regarding spatial
scale, temporal scale, and plants-animal interactions will vary depending on their focus of
restoration. Spatial scale influences both the spatial extent and configuration of restoration
actions, as well as spatial processes. Time is a valuable factor for both plant-based and animalbased restoration; however, they differ significantly. Interactions between plants and animals
may have complex consequences that create dilemmas for restoration managers (McAlpine,
Clive, et al., 41). The authors suggested four strategies to create a more unified approach to the
restoration of fragmented landscapes, 1) strengthen collaboration between plant and animal
ecologists, 2) give priority to restoration projects that will benefit both plants and animals, 3)
pay greater attention to restoring plant-animal interactions, and 4) adopt a systematic
restoration planning approach (McAlpine, Clive, et al., 43).
I have faith that we can improve our techniques for restoration, even if it is not possible to
fully restore a site to a historic reference condition. As noted in a paper, “Quandaries of a
decade-long restoration experiment trying to reduce invasive species: beat them, join them,
give up, or start over?”, where researchers concluded that perhaps they could never completely
walk away from management, and they had to accept that some ecosystems could not be
returned to an all-native state. However, they acknowledge that their circumstances were the
worst-case scenario. Despite that, I still believe that we should be thinking of restoring to a
sustainable novel state.
Conservation Ecology
3. One theme we talked about in both disturbance ecology and conservation ecology is pattern
influencing process and process influencing pattern. Imagine a large heterogeneous landscape.
Explain how the pattern of heterogeneity on the ground might affect the process of a
disturbance event (such as a fire, flood or windstorm) and the subsequent recovery from that
disturbance. For instance, you should touch upon whether the disturbance would affect the
entire landscape in the same way. (45 points)
Landscape ecology is crucial to applied ecology. It is founded on the principle that
spatial patterns affect ecological patterns, which in turn affect spatial patterns (asynchronous
lecture 4/20). A few examples of this include dust bowl sediments from the Western plains,
burying Eastern prairies, acid rain originating from distant emissions wipes out Canadian fish,
wetland drainage decimates nearby wildlife populations, and heat from the surrounding desert
desiccates an oasis. In each of these cases, two or more ecosystems are linked and interacting.
The heat from the desert, the desert ecosystem desiccating an oasis, is connected to the oasis
ecosystem. Habitat destruction upper river, higher up in the watershed, impacts and causes
widespread flooding downriver (asynchronous lecture 4/20). Those two ecosystems are linked
(potentially more than those two ecosystems), and they're interacting.
Another example is looking at housing developments that are placed within the forested
ecosystems. These developments will affect the hydrologic processes in the area. Related to
that is the pattern of highways through a forested ecosystem that affects large animals'
movements and processes. Ecosystem function depends on this interplay of pattern and
process (asynchronous lecture 4/20). Humans play an enormous role in landscape ecology by
creating and affecting these relationships. These pattern and process relationships have
considerable implications for resource managers (asynchronous lecture 4/20). This is especially
true when considering a sizeable heterogeneous landscape which will affect the process of a
disturbance event (such as a fire, flood, or windstorm) and the subsequent recovery from that
disturbance. A disturbance will affect the entire heterogeneous landscape in different ways;
this is based on the idea that neighborhood effects play a significant role in forest succession
after disturbance. A disturbance event such as fire will create areas that are heavily burned and
within close proximity unburned areas throughout a large heterogeneous landscape. These
unburned areas will play a prominent role in the eventual succession of this disturbed patch
along with the plant species composition, energy and water distribution, and metapopulations
(asynchronous lecture 4/20).
Edge effects are responsible for modifying energy and water distribution and
metapopulations, a group of populations separated by space but consisting of the same
species. These are special spatially separated populations, which can interact as individual
members move from one population to another. The individuals within this population can
move between these two populations in space and time. Individuals within a populated patch
that move into an empty patch will likely die out. Metapopulations are dependent on the
number of distinct populations and the spatial arrangement of habitat patches. The probability
of a habitat patch being occupied at any time is at least partially dependent on its proximity to
other habitat patches (asynchronous lecture 4/20). Since most landscapes nowadays are
fragmented, and fragmentation is one of the leading causes of biodiversity loss, a disturbance
event such as a fire or a flood will impact metapopulations, potentially have significant
consequences for the entire population. These smaller populations are exposed to other
threats that compound their extinction risk. They are at greater risk of random events, such as a
disturbance event that could wipe out most of a population (asynchronous lecture 4/20). Not
all fragmentation is created equally either. Depending upon how the land is fragmented there
will be different ratios of interior and edge habitat. This is critical for species which require a
good core habitat or are interior-dependent, usually generalist species are edge-dependent.
Unfortunately, fragmentation is usually done in such a way that it creates more edge habitat
than interior. Edge effects are referred to as the changes in population or community structures
that occur at the boundary of two habitats. For edges you have in that increased light,
decreased humidity, which have considerable impact on the species that live there. All these
factors mentioned will influence the subsequent recovery of a large heterogeneous landscape
from a disturbance event.
Works Cited
Cordell, Susan, et al. “Quandaries of a Decade-Long Restoration Experiment Trying to Reduce
Invasive Species: Beat Them, Join Them, Give up, or Start over?” Restoration Ecology, vol. 24,
no. 2, 2016, pp. 139–144., doi:10.1111/rec.12321.
McAlpine, Clive, et al. “Integrating Plant- and Animal-Based Perspectives for More Effective
Restoration of Biodiversity.” Frontiers in Ecology and the Environment, vol. 14, no. 1,
2016, pp. 37–45., doi:10.1002/16-0108.1.
Slobodkin, L. B. “Intellectual Problems of Applied Ecology.” BioScience, vol. 38, no. 5, 1988, pp.
337–337., doi:10.2307/1310736.
Van de Koppel, Johan, et al. “Ecology of Ecosystems and Biotic Communities.” Restoration
Ecology, 2012, pp. 59–72., doi:10.1002/9781118223130.ch6.
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