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1.
Trade-offs between tree cover, carbon storage and floristic biodiversity in reforesting landscapes 总被引:1,自引:2,他引:1
Jaclyn M. Hall Tracy Van Holt Amy E. Daniels Vincent Balthazar Eric F. Lambin 《Landscape Ecology》2012,27(8):1135-1147
This study explores the relationships between an increase in tree cover area (i.e., natural and planted-tree land covers) and changes in forest carbon storage and the potential of a landscape to provide habitat for native floristic biodiversity. Four areas experiencing an increase in tree cover were analyzed. We developed a metric estimating the potential to support native biodiversity based on tree cover type (plantation or natural forests) and the landscape pattern of natural and anthropogenic land covers. We used published estimates for forest and plantation carbon stocks for each region. Focus regions in northwestern Costa Rica, northern Vietnam, southern Chile and highland Ecuador all showed an increase in tree cover area of 390?%, 260?%, 123?% and 418?%, respectively. Landscapes experiencing increases in natural secondary forest also experienced an increase in carbon stored above and below ground, and in the potential to support native floristic biodiversity. Study landscapes in Chile and Ecuador experiencing an expansion of exotic plantations saw their carbon stock decrease along with their potential to support native floristic biodiversity. This study shows that an increase in forest area does not necessarily imply an increased provision of ecosystem services when landscapes are reforesting with monoculture plantations of exotic tree species. Changes in the support of native biodiversity and the carbon stored in pulp rotation plantations, along with other ecosystem services, should be fully considered before implementing reforestation projects. 相似文献
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3.
Landscape cohesion: an index for the conservation potential of landscapes for biodiversity 总被引:14,自引:6,他引:14
In urbanising landscapes, planning for sustainable biodiversity occurs in a context of multifunctional land use. Important
conditions for species persistence are habitat quality, the amount and configuration of habitat and the permeability of the
landscape matrix. For planning purposes, these determinants should be integrated into simple indicators for spatial conditions
of persistence probability. We propose a framework of three related indices. The cohesion index is based on the ecology of
metapopulations in a habitat network. We discuss how an indicator for species persistence in such a network could be developed.
To translate this network index into an area index, we propose the concept of spatial cohesion. Habitat cohesion and spatial
cohesion are defined and measured for single species or, at best, for species profiles. Since species differ in their perception
of the same landscape, different species will rate different values of these indices for the same landscape. Because landscapes
are rarely planned for single species, we further propose the index of landscape cohesion, which integrates the spatial cohesion
indices of different species. Indices based on these concepts can be built into GIS tools for landscape assessment. We illustrate
different applications of these indices, and emphasise the distinction between ecological and political decisions in developing
and applying such tools.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
4.
The influence of thematic resolution on metric selection for biodiversity monitoring in agricultural landscapes 总被引:4,自引:3,他引:4
Debra Bailey Regula Billeter Stéphanie Aviron Oliver Schweiger Felix Herzog 《Landscape Ecology》2007,22(3):461-473
The objective of this paper is to investigate the relationship between landscape pattern metrics and agricultural biodiversity
at the Temperate European scale, exploring the role of thematic resolution and a suite of biological and functional groups.
Factor analyses to select landscape-level metrics were undertaken on 25 landscapes classified at four levels of thematic resolution.
The landscapes were located within seven countries. The different resolutions were considered appropriate to taxonomic and
functional group diversity. As class-level metrics are often better correlated to ecological response, the landscape-level
metric subsets gained through exploratory analysis were additionally used to guide the selection of class-level metric subsets.
Linear mixed models were then used to detect correlations between landscape- and class-level metrics and species richness
values. Taxonomic groups with differing requirements (plants, birds, different arthropod groups) and also functional arthropod
groups were examined. At the coarse scale of thematic resolution grain metrics (patch density, largest patch index) emerged
as rough indicators for the different biological groups whilst at the fine scale a diversity metric (e.g. Simpson’s diversity
index) was appropriate. The intermediate thematic resolution offered most promise for biodiversity monitoring. Metrics included
largest patch index, edge density, nearest neighbour, the proximity index, circle and Simpson’s diversity index. We suggest
two possible applications of these metrics in the context of biodiversity monitoring and the identification of biodiversity
hot spots in European agricultural landscapes. 相似文献
5.
Helena Tukiainen Janne Alahuhta Richard Field Terhi Ala-Hulkko Raino Lampinen Jan Hjort 《Landscape Ecology》2017,32(5):1049-1063
Context
‘Conserving Nature’s stage’ has been advanced as an important conservation principle because of known links between biodiversity and abiotic environmental diversity, especially in sensitive high-latitude environments and at the landscape scale. However these links have not been examined across gradients of human impact on the landscape.Objectives
To (1) analyze the relationships between land-use intensity and both landscape-scale biodiversity and geodiversity, and (2) assess the contributions of geodiversity, climate and spatial variables to explaining vascular plant species richness in landscapes of low, moderate and high human impact.Methods
We used generalized additive models (GAMs) to analyze relationships between land-use intensity and both geodiversity (geological, geomorphological and hydrological richness) and plant species richness in 6191 1-km2 grid squares across Finland. We used linear regression-based variation partitioning (VP) to assess contributions of climate, geodiversity and spatial variable groups to accounting for spatial variation in species richness.Results
In GAMs, geodiversity correlated negatively, and plant species richness positively, with land-use intensity. Both relationships were non-linear. In VP, geodiversity best accounted for species richness in areas of moderate to high human impact. These overall contributions were mainly due to variation explained jointly with climate, which dominated the models. Independent geodiversity contributions were highest in pristine environments, but low throughout.Conclusions
Human action increases biodiversity but may reduce geodiversity, at landscape scale in high-latitude environments. Better understanding of the connections between biodiversity and abiotic environment along changing land-use gradients is essential in developing sustainable measures to conserve biodiversity under global change.6.
Natural ecosystems are life-supporting systems providing diverse ecosystem services (ESs) and benefits to human societies:
e.g., food and clean water, recreation opportunities or climate regulation. The contribution of natural and semi-natural ecosystems
to the provision of such services depends to a large extent on vegetation structure and composition, which, in turn, change
as a result of interactions between human decisions about land management, and spontaneous biological and environmental processes.
Rational management of these dynamic ecosystems requires an ability to predict short- and long-term effects of management
decisions on the desired ESs. The vegetation then contributes to, and modifies, the products and services obtained from the
land. We applied mathematical modeling to study these complex relationships. We developed a model for a Mediterranean ecosystem
which predicts the dynamics of multiple services in response to management scenarios, mediated by vegetation changes. Six
representative ESs representing different groups were selected, based on available scientific information, for a detailed
study: (1) density of geophytes, (2) potential contribution to honey production, (3) energy density of fleshy fruits foraged
by birds, (4) forage for goats, (5) forage for cattle, and (6) carbon retention in woody plants. Mean contributions to each
service by different vegetation cover types were estimated, and the overall service provided by the site was calculated as
a weighted mean of these contributions. Services were measured in their appropriate units and subsequently standardized to
a percentage of the maximum value observed in the study area. We attempted to combine all studied ESs, despite their different
nature, into one “ESs basket”. This paper presents the dynamics of simulated vegetation composition and values of services
in response to management scenarios involving grazing, fire and their combinations. Our approach can help land managers to
evaluate alternative management scenarios by presenting the “services basket” obtained from the entire managed area. 相似文献
7.
The relationship and feedback between landscape pattern, function and process serve to describe the behavior of a regional
landscape. Based on landscape function characteristics such as biological productivity, soil nutrient content, vegetative
cover, etc., a quantitative method and digital model for analyzing evolving landscape functionality in the headwaters area
of the Yellow River in the People's Republic of China were devised. Through the analysis of three-phase remote sensing data
from 1975, 1985 and 1995 and based upon the well-defined characteristics of this region's evolving landscape over the past
30 years, the attendant ecology of the different functional landscape ecotypes was investigated. Between 1975 and 1995 the
area of AC&S (alpine cold meadow and steppe) in the source area of the Yellow River has decreased by 27.25%, ACSW (alpine
cold swamp meadow) has decreased by 27.04%, ALP (alpine steppe) by 38.18% and lakes by 9.78%. The grass biomass production
decreased by 752.37 Gg, of which AC&S meadows accounted for 83.8% of these losses. The overall stock capacity of the headwaters
area of the Yellow River decreased by 518.36 thousand sheep units. Soil nutrients showed a similar pattern, soil nutrient
loss was greater from 1985–1995 than from 1975–1985. Changes in the overall ecological functionality of the area were not
simply a result of a summation of the changes associated with individual evolving landscapes, but rather an integration of
positive and negative influences. Landscape evolution occurs in two main directions: degradation and strengthening (expanding
and improving). An understanding of the direction, force and integration of parameters influencing landscape evolution as
it impacts the attending ecosystems can allow one to foresee how the landscape of the Yellow River source area will evolve
in the coming years.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
8.
An aggregation index (AI) to quantify spatial patterns of landscapes 总被引:43,自引:0,他引:43
There is often need to measure aggregation levels of spatial patterns within a single map class in landscape ecological studies. The contagion index (CI), shape index (SI), and probability of adjacency of the same class (Qi), all have certain limits when measuring aggregation of spatial patterns. We have developed an aggregation index (AI) that is class specific and independent of landscape composition. AI assumes that a class with the highest level of aggregation (AI =1) is comprised of pixels sharing the most possible edges. A class whose pixels share no edges (completely disaggregated) has the lowest level of aggregation (AI =0). AI is similar to SI and Qi, but it calculates aggregation more precisely than the latter two. We have evaluated the performance of AI under varied levels of (1) aggregation, (2) number of patches, (3) spatial resolutions, and (4) real species distribution maps at various spatial scales. AI was able to produce reasonable results under all these circumstances. Since it is class specific, it is more precise than CI, which measures overall landscape aggregation. Thus, AI provides a quantitative basis to correlate the spatial pattern of a class with a specific process. Since AI is a ratio variable, map units do not affect the calculation. It can be compared between classes from the same or different landscapes, or even the same classes from the same landscape under different resolutions. 相似文献
9.
We developed metrics at a landscape scale to evaluate the costs and rewards experienced by large herbivores while foraging
in natural vegetation with patchy anti-herbivore plant structures. We show an application of these metrics to the analysis
of 16,000 records of positions at successive 1 min intervals of free-ranging ewes (Ovis aries) harnessed with Global-Positioning-System (GPS) loggers, in a large paddock of the Patagonian Monte shrublands (Argentina).
Dominant shrubs in the area display numerous anti-herbivore defenses (spiny-resinous leaves, thorny stems, etc.) protecting
them from grazing and herbivore trampling. Preferred grasses and forbs constitute a minor part of aboveground plant biomass
and grow in relatively open areas among or around shrub patches. We mapped the movement speed of ewes onto high-resolution
aerial photographs of the grazed paddocks and estimated costs and rewards along their paths based on algorithms of surface
cost theory. Ewes explored areas of sparse vegetation at low speeds compatible with predominant grazing, and increased their
speed when crossing denser shrubby patches. The cost algorithm was applied to evaluate daily searching costs as well as grazing
rewards in relation to the length of daily searching paths. The observed path lengths and search speeds were consistent with
those that compensate costs and rewards of the grazing activities as estimated by the surface cost analysis. We conclude that
the technique presented here constitutes a valuable tool to quantify the effect of landscape characteristics on behavioral
traits of grazing animals in similar environments. 相似文献
10.
Sciusco Pietro Chen Jiquan Abraha Michael Lei Cheyenne Robertson G. Philip Lafortezza Raffaele Shirkey Gabriela Ouyang Zutao Zhang Rong John Ranjeet 《Landscape Ecology》2020,35(6):1385-1402
Landscape Ecology - Albedo can be used to quantify ecosystem and landscape contributions to local and global climate. Such contributions are conventionally expressed as radiative forcing (RF) and... 相似文献
11.
Designing agricultural landscapes for natural pest control: a transdisciplinary approach in the Hoeksche Waard (The Netherlands) 总被引:1,自引:1,他引:1
Eveliene G. Steingröver Willemien Geertsema Walter K. R. E. van Wingerden 《Landscape Ecology》2010,25(6):825-838
The green–blue network of semi-natural non-crop landscape elements in agricultural landscapes has the potential to enhance
natural pest control by providing various resources for the survival of beneficial insects that suppress crop pests. A study
was done in the Hoeksche Waard to explore how generic scientific knowledge about the relationship between the spatial structure
of the green–blue network and enhancement of natural pest control can be applied by stakeholders. The Hoeksche Waard is an
agricultural area in the Netherlands, characterized by arable fields and an extensive network of dikes, creeks, ditches and
field margins. Together with stakeholders from the area the research team developed spatial norms and design rules for the
design of a green–blue network that supports natural pest control. The stakeholders represented different interests in the
area: farmers, nature and landscape conservationists, water managers, and local and regional politicians. Knowledge about
the spatial relationship among beneficial insects, pests and landscape structure is incomplete. We conclude that to apply
scientific knowledge about natural pest control and the role of green–blue networks to stakeholders so that they can apply
it in landscape change, knowledge transfer has to be transparent, area specific, understandable, practical and incorporate
local knowledge. 相似文献
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13.
Morteza Asgarzadeh Kourosh Vahdati Mahmoud Lotfi Mostafa Arab Alireza Babaei Farzaneh Naderi Mohammad Pir Soufi Ghazaleh Rouhani 《Urban Forestry & Urban Greening》2014,13(3):450-458
Choosing appropriate plants for urban landscapes is vital to avoid potential financial and environmental losses that may occur if all selection parameters are not taken into account. A methodology has been developed to assist landscape architects, planting designers, and urban horticulturists in the plant selection process. Tehran has been picked as a case study due to its arid and semi-arid climate which poses more challenges in front of an expert. After grouping plants, selection parameters have been defined for each plant group. Plant species were comparatively graded for each parameter by a group of eight specialists. Analytical hierarchy process (AHP) technique and hierarchical cluster analysis have been utilized to find the most adaptable plant species for the area according to the main selection parameters of zone tolerance, urban conditions, esthetics, maintenance, growth characteristics, and specific features. Several new plants were ranked high in the final tables suggesting that the urban landscape of Tehran has a great potential to become more attractive, less allergic, and less costly, as well as consuming less water. Before introducing new plants to the urban environment, they should be experimented on in small numbers for several years to confirm that they will not change the ecology of the whole region through invasion or posing a threat to any local plant species. 相似文献
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15.
On Shimokamagari, an island of the Seto Island Sea, patterns of vegetation in the landscape were studied using vegetation
maps. Relationships between social and economic changes, site conditions and the vegetation were examined from a historical
perspective. In the process of economic development, mandarin orange production became important on this island. However,
over-production, a reduction in the price of mandarin oranges and low-temperature damage to orange trees caused large citrus
orchards to be abandoned. A plant community dominated by kudzu appeared in the abandoned orchards and the pine forests, as
well. These changes in orchards were connected with the natural site conditions, such as soil, geology, inclination, elevation,
direction of slope, and also with artificial conditions, such as density of working paths. Another factor causing change was
the replacement of the organic fertilizer of litter from forests by chemical fertilizer since the 1960's. As a result, medium
and small forests of pine became tall forests and tall forests of pine changed into tall oak forests. In the human-dominated
areas, the major factors affecting the process of vegetation were economic activities, and after the abandonment of the farm-lands,
forest succession were controlled by natural site conditions.
This paper was presented at the World-Congress of Landscape Ecology in Ottawa, 1991
Titles are tentative translations for original titles in Japanese by the authors. 相似文献
16.
Cubizolle H. Tourman A. Argant J. Porteret J. Oberlin C. Serieyssol K. 《Landscape Ecology》2003,18(3):227-238
Mires are rare, unique environments that greatly contribute to biodiversity and occupy key functions in the hydrological cycle, but today many of these ecosystems are menaced, making conservation measures necessary. The efficiency of these measures is partly related to our knowledge of their origins and their development, a question rarely addressed. In this paper we examine the development of mires during the 10.000 last years (Holocene) in the eastern Massif Central, France, focusing on the contributions of climate change and human activities. Radiocarbon dates of the basal layers of 63 sites show that many mires formed around 7500 BP. During the Holocene, many mires were formed in the Atlantic period, characterised by warmer and wetter climatic conditions. At shorter time scales of 103–102 years, several other factors are related to peat inception, including topography, geomorphology and superficial geology, vegetation successions and human-induced changes. There is evidence that the building of small dams in headwater streams during the Iron age induced local water logging which then lead to the initiation and growth of mires. The influence of Bronze age communities is further demonstrated by new pollen analysis results. Forest clearing and grazing also favoured soil water logging, enabling peat inception. We consider human societies to be responsible for the formation of some mires. Human activities can be considered to having taken part in the development of the European biodiversity at least during the last 5 millennium.This revised version was published online in May 2005 with corrections to the Cover Date. 相似文献
17.
Landscape Ecology - Conservation planning increasingly needs to be effective in areas that are influenced by anthropogenic land uses, yet many planning tools do not give equal consideration to... 相似文献
18.
Context
The conservation value of residential landscapes is becoming increasingly apparent in our urbanizing world. The ecological characteristics of residential areas are largely determined by the decisions of many individual “managers.” In these complex socio-ecological systems, it is important to understand the factors that motivate human decision-making.Objectives
Our first objective was to quantify wildlife resources and management activities in residential landscapes and compare vegetation in front and back yards. Our second objective was to test three hypotheses linked with variation in yards: socioeconomic characteristics, neighborhood design factors, and perceptions of neighborhood birds.Methods
We conducted surveys of over 900 residents in 25 Chicago-area neighborhoods to examine the wildlife resources contained in front and back yards and the social factors associated with variation in yards. We used a multi-scalar approach to examine among-yard and among-neighborhood variation in residential landscapes.Results
Results indicate that back yards contain more wildlife resources than front yards, including greater vegetation complexity, more plants with fruit/berries, and more plants intended to attract birds. Furthermore, different hypotheses explain variation in front and back yards. Perceptions of birds were most important in explaining variation in back yard vegetation and wildlife-friendly resources per parcel, while neighbors’ yards and socioeconomic characteristics best explained front yard vegetation.Conclusions
This study demonstrates the importance of back yards as an unexplored and underestimated resource for biodiversity. In addition, the results provide insight into the complex factors linked with yard decisions, notably that residents’ connections with neighborhood birds appear to translate to on-the-ground actions.19.
G.H. Stewart C.D. Meurk M.E. Ignatieva H.L. Buckley A. Magueur B.S. Case M. Hudson M. Parker 《Urban Forestry & Urban Greening》2009,8(3):149-162
Urban forests are increasingly valued for multiple benefits such as amenity, cultural values, native biodiversity, ecosystem services, and carbon sequestration. Urban biodiversity in particular, is the new focus although global homogenisation is undermining regional differentiation. In the northern hemisphere (e.g., Canada and USA) and in the southern hemisphere, particularly in countries like South Africa, Australia, South America and New Zealand, local biodiversity is further impacted by historical colonisation from Europe. After several centuries, urban forests are now composed of synthetic and spontaneous mixtures of native species, and exotic species from around the temperate world (e.g., Europe, North and South America, South Africa, Asia). As far as we are aware no-one has carried out in-depth study of these synthetic forests in any Southern Hemisphere city. Here we describe the composition, structure, and biodiversity conservation imperatives of urban temperate forests at 90 random locations in Christchurch city, New Zealand.We document considerable plant diversity; the total number of species encountered in the 253 sampled urban forest patches was 486. Despite this incredibly variable data set, our ability to explain variation in species richness was surprisingly good and clearly indicates that total species richness was higher in larger patches with greater litter and vegetation cover, and taller canopy height. Species richness was also higher in patches surrounded by higher population densities and closer to very large native forest patches. Native species richness was higher in patches with higher soil pH, lower canopy height, and greater litter cover and in patches closer to very large native forest patches indicating dispersal out of native areas and into gardens. Eight distinct forest communities were identified by Two-Way INdicator SPecies ANalysis (TWINSPAN) using the occurrence of 241 species that occurred in more than two out of all 253 forest patches.Christchurch urban forest canopies were dominated by exotic tree species in parklands and in street tree plantings (linear parkland). Native tree and shrub species were not as common in public spaces but their overall density high in residential gardens. There was some explanatory power in our data, since less deprivation resulted in greater diversity and density, and more native species, which in turn is associated with private ownership. We hypothesise that a number of other factors, which were not well reflected in our measured environmental variables, are responsible for much of the remaining variation in the plant community structure, e.g., advertising, peoples choice. For a more sustainable asset base of native trees in New Zealand cities we need more, longer-lived native species, in large public spaces, including a greater proportion of species that bear fruit and nectar suitable for native wildlife. We may then achieve cities with ecological integrity that present multiple historical dimensions, and sequester carbon in legible landscapes. 相似文献
20.
Little information is available regarding the landscape ecology of woodland invertebrate species with limited dispersal ability.
An investigation was therefore conducted within woodland fragments in an agricultural landscape for the flightless wood cricket
(Nemobius sylvestris) on the Isle of Wight, UK. The current pattern of distribution of the species, established during a field survey, was related
to measures of habitat availability and habitat isolation/fragmentation. Results revealed that wood cricket populations were
patchily distributed and mainly found in relatively large mature woodland fragments situated closely (<50 m) to another occupied
site. Although the occurrence of wood cricket was related to fragment area, isolation, habitat availability and woodland age,
a logistic regression model revealed that presence of the species was most accurately predicted by fragment isolation and
area alone. These results highlight the vulnerability of relatively immobile woodland invertebrate species, such as wood cricket,
to the impacts of habitat loss and fragmentation. 相似文献