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211.
In many regions of the world, fires are primarily of anthropogenic origin. In northwestern Patagonia, the number of fires
is not correlated with meteorological variables, but is concentrated in urban areas. This study was conducted in the wildland–urban
interface (WUI) area of San Carlos de Bariloche (Patagonia, Argentina), within the Nahuel Huapi National Park. WUI fires are
particularly problematic because, besides people and goods, they represent a danger to protected areas. We studied the relationship
between fire records and socioeconomic indicators within the WUI of San Carlos de Bariloche. We conducted a Multiple Correspondence
Factorial Analysis and an Ascendant Hierarchical Classification of the city neighborhoods. The results show that the neighborhoods
in Bariloche can be divided into three classes: High Socioeconomic Fire Risk neighborhoods, including neighborhoods with the
highest fire rates, where people have low instruction level, high levels of unsatisfied basic needs and high unemployment
levels; Low Socioeconomic Fire Risk neighborhoods, that groups neighborhoods which present the opposite characterization,
and Moderate Socioeconomic Fire Risk neighborhoods, which are more heterogeneous. Once neighborhoods were classified, a Socioeconomic
Fire Risk map was generated, supplementing the existing WUI Fire Danger map. Our results emphasize the relevance of socioeconomic
variables to fire policies. 相似文献
212.
Farm Crops Depredation by European Bison (Bison bonasus) in the Vicinity of Forest Habitats in Northeastern Poland 总被引:1,自引:0,他引:1
European bison, the largest mammal in Europe, after being exterminated in the wild and then restored during the 20th century is still listed by the International Union for Conservation of Nature (IUCN Red List of Threatened Species) as a species vulnerable to extinction. However, the increasing number of European bison, through creation of new and expansion of existing populations strongly increases the risk of human-bison conflict in the near future. We analyzed the depredation of farm crops by bison and the factors influencing the level of damage in the vicinity of two forest areas inhabited by bison in northeastern Poland. Between 2000 and 2010, the total cost of compensation was 196,200. The level of damage and amount of compensation was increasing from year to year in both forests and correlated with the number of bison. The majority of damage (57?% of cases) was recorded in winter (December-March). Snow depth and temperature did not influence the frequency of damage. The incidences of damage increased with decreasing distance from the woodland patches, therefore, 69?% of cases in Bia?owie?a Forest, and 80?% in Knyszyn Forest were recorded closer than 0.5?km from nearest woodland patch. The majority of the crops damaged by bison were cereals (61?%) but also hay (20?%) and rape (13?%). When compared to the availability of crops, bison strongly selected rape and rye in both regions. This study is the first addressing the increasing problem of human-bison conflict in re-introduced populations and analyzing long-term data on crop depredation. Such situations probably occur in the majority of growing and expanding bison populations, however, it has not yet to be monitored and is rather neglected in post-Soviet countries. 相似文献
213.
The present study aims to identify the potential habitat for swamp deer (Cervus duvauceli duvauceli Cuvier) in Jhilmil Jheel Conservation Reserve in the Uttarakhand province of India using multi-criteria analysis. The study
area represents one of the last remnant habitats of the flagship species, the swamp deer in Uttarakhand, which is considered
as vulnerable. The study showed that only 6.08% of the study area (225 km2) was highly suitable to suitable for the swamp deer. An area of 135.52 km2 (60.23%) turned out to be moderately suitable. Within the officially designated Conservation Reserve (area 37.84 km2), 10.91% (4.13 km2) area was found highly suitable to suitable, while 74.19% (28.07 km2) happens to be moderately suitable. Only 14 km2 area, which was found as suitable habitat for swamp deer falls short of the space required by a population of 134 animals.
The problem could be mitigated if the agricultural land (2.47 km2) adjacent to the Jhilmil Jheel is brought under the Reserve management. This would provide additional area to meet the fodder
requirement. The study brings out a particularly grim situation with limited options for conservation and management of the
swamp deer in the Indo-Gangetic plains. It also emphasizes the role of geospatial techniques in quick appraisal of habitat
attributes and identification of potential sites for protected areas. 相似文献
214.
The study investigated vegetative and soil properties in four created mitigation wetlands, ranging in age from three to ten
years, all created in the Virginia Piedmont. Vegetation attributes included percent cover, richness (S), diversity (H′), floristic
quality assessment index (FQAI), prevalence index (PI), and productivity [i.e., peak above-ground biomass (AGB) and below-ground
biomass]. Soil attributes included soil organic matter (SOM), gravimetric soil moisture (GSM), pH, and bulk density (Db) for the top 10 cm. Species dominance (e.g., Juncus effusus, Scirpus cyperinus, Arthraxon hispidus) led to a lack of differences in vegetative attributes between sites. However, site-based differences were found for GSM,
pH, and SOM (P < 0.001). Soil attributes were analyzed using Euclidean cluster analysis, resulting in four soil condition (SC) categories
where plots were grouped based on common attribute levels (i.e., SC1 > SC2 > SC3 > SC4, trended more to less developed). When
vegetation attributes were compared between SC groups, greater SOM, lower Db, more circumneutral pH, and higher GSM, all indicative of maturation, were associated with higher H′ (P < 0.05), FQAI (P < 0.05), and total and volunteer percent cover (P < 0.05), and lower AGB (P < 0.001), PI (P < 0.05), and seeded percent cover (P < 0.05). The outcome of the study shows that site age does not necessarily equate with site development with soil and vegetation
developmental rates varying both within and among sites. The inclusion of soil attributes in post-construction monitoring
should be required to enhance our understanding and prediction of developmental trajectory of created mitigation wetlands. 相似文献
215.
Groninger JW 《Environmental management》2012,49(4):833-845
Foreign and domestic government agencies and other international organizations pursue reforestation programs in rural upper
watershed areas of Afghanistan over the past decade to alleviate poverty, combat the insurgency and rehabilitate a depleted
forest resource base. Popular programs incorporate cash-for-work to conduct hillside terracing, check dam construction and
tree-planting for nut production, fuel wood, timber, dune stabilization, and erosion abatement. Programmatic approaches have
varied as a function of accessibility, security and local objectives. Uncertain land tenure and use rights, weak local environmental
management capacity, and a focus on agricultural production to meet immediate needs limit interest, nationally and locally.
Unreliable security, a lack of high quality tree planting stock, limited technical knowledge and coordination among government
agencies, and poor security hamper program expansion. Reforestation success would be most likely where these issues are least
acute. The Afghan government should focus on supporting community based natural resource management, developing and disseminating
improved conservation tree nursery strategies, and promoting watershed management schemes that incorporate forestry, range
management and agronomic production. Reforestation practitioners could benefit from the human and material resources now present
as part of the international war effort. Successes and failures encountered in Afghanistan should be considered in order to
address similar problems in insecure regions elsewhere when reforestation may help reverse environmental degradation and contribute
to broader social stabilization efforts. 相似文献
216.
Corace RG Shartell LM Schulte LA Brininger WL McDowell MK Kashian DM 《Environmental management》2012,49(2):359-371
To facilitate forest planning and management on National Wildlife Refuges, we synthesized multiple data sources to describe
land ownership patterns, land cover, landscape pattern, and changes in forest composition for four ecoregions and their associated
refuges of the Upper Midwest. We related observed patterns to ecological processes important for forest conservation and restoration,
with specific attention to refuge patterns of importance for forest landbirds of conservation priority. The large amount of
public land within the ecoregions (31–80%) suggests that opportunities exist for coarse and meso-scale approaches to conserving
and restoring ecological processes affecting the refuges, particularly historical fire regimes. Forests dominate both ecoregions
and refuges, but refuge forest patches are generally larger and more aggregated than in associated ecoregions. Broadleaf taxa
have increased in dominance in the ecoregions and displaced fire-dependent taxa such as pine (Pinus spp.) and other coniferous species; these changes in forest composition have likely also affected refuge forests. Despite
compositional changes, larger forest patches on refuges suggests that they may provide better habitat for area-sensitive forest
landbirds of mature, compositionally diverse forests than surrounding lands if management continues to promote increased patch
size. We reason that although fine-scale research and monitoring for species of conservation priority is important, broad
scale (ecoregional) assessments provide crucial context for effective forest and wildlife management in protected areas. 相似文献
217.
The potential of epiphytic hydrocarbon-utilizing bacteria on legume leaves for attenuation of atmospheric hydrocarbon pollutants 总被引:1,自引:0,他引:1
The leaves of two legumes, peas and beans, harbored on their surfaces up to 9×10? cells g?1 of oil-utilizing bacteria. Less numbers, up to 5×10? cells g?1 inhabited leaves of two nonlegume crops, namely tomato and sunflower. Older leaves accommodated more of such bacteria than younger ones. Plants raised in oily environments were colonized by much more oil-utilizing bacteria than those raised in pristine (oil-free) environments. Similar numbers were counted on the same media in which nitrogen salt was deleted, indicating that most phyllospheric bacteria were probably diazotrophic. Most dominant were Microbacterium spp. followed by Rhodococcus spp., Citrobacter freundii, in addition to several other minor species. The pure bacterial isolates could utilize leaf tissue hydrocarbons, and consume considerable proportions of crude oil, phenanthrene (an aromatic hydrocarbon) and n-octadecane (an alkane) in batch cultures. Bacterial consortia on fresh (but not on previously autoclaved) leaves of peas and beans could also consume substantial proportions of the surrounding volatile oil hydrocarbons in closed microcosms. It was concluded that phytoremediation through phyllosphere technology could be useful in remediating atmospheric hydrocarbon pollutants. 相似文献
218.
Estimating the Cumulative Ecological Effect of Local Scale Landscape Changes in South Florida 总被引:1,自引:0,他引:1
Hogan DM Labiosa W Pearlstine L Hallac D Strong D Hearn P Bernknopf R 《Environmental management》2012,49(2):502-515
Ecosystem restoration in south Florida is a state and national priority centered on the Everglades wetlands. However, urban
development pressures affect the restoration potential and remaining habitat functions of the natural undeveloped areas. Land
use (LU) planning often focuses at the local level, but a better understanding of the cumulative effects of small projects
at the landscape level is needed to support ecosystem restoration and preservation. The South Florida Ecosystem Portfolio
Model (SFL EPM) is a regional LU planning tool developed to help stakeholders visualize LU scenario evaluation and improve
communication about regional effects of LU decisions. One component of the SFL EPM is ecological value (EV), which is evaluated
through modeled ecological criteria related to ecosystem services using metrics for (1) biodiversity potential, (2) threatened
and endangered species, (3) rare and unique habitats, (4) landscape pattern and fragmentation, (5) water quality buffer potential,
and (6) ecological restoration potential. In this article, we demonstrate the calculation of EV using two case studies: (1)
assessing altered EV in the Biscayne Gateway area by comparing 2004 LU to potential LU in 2025 and 2050, and (2) the cumulative
impact of adding limestone mines south of Miami. Our analyses spatially convey changing regional EV resulting from conversion
of local natural and agricultural areas to urban, industrial, or extractive use. Different simulated local LU scenarios may
result in different alterations in calculated regional EV. These case studies demonstrate methods that may facilitate evaluation
of potential future LU patterns and incorporate EV into decision making. 相似文献
219.
Santoro R Jucker T Prisco I Carboni M Battisti C Acosta AT 《Environmental management》2012,49(3):534-542
Sandy coastlines are sensitive ecosystems where human activities can have considerable negative impacts. In particular, trampling
by beach visitors is a disturbance that affects dune vegetation both at the species and community level. In this study we
assess the effects of the limitation of human trampling on dune vegetation in a coastal protected area of Central Italy. We
compare plant species diversity in two recently fenced sectors with that of an unfenced area (and therefore subject to human
trampling) using rarefaction curves and a diversity/dominance approach during a two year study period. Our results indicate
that limiting human trampling seems to be a key factor in driving changes in the plant diversity of dune systems. In 2007
the regression lines of species abundance as a function of rank showed steep slopes and high Y-intercept values in all sectors, indicating a comparable level of stress and dominance across the entire study site. On the
contrary, in 2009 the regression lines of the two fenced sectors clearly diverge from that of the open sector, showing less
steep slopes. This change in the slopes of the tendency lines, evidenced by the diversity/dominance diagrams and related to
an increase in species diversity, suggests the recovery of plant communities in the two fences between 2007 and 2009. In general,
plant communities subject to trampling tended to be poorer in species and less structured, since only dominant and tolerant
plant species persisted. Furthermore, limiting trampling appears to have produced positive changes in the dune vegetation
assemblage after a period of only two years. These results are encouraging for the management of coastal dune systems. They
highlight how a simple and cost-effective management strategy, based on passive recovery conservation measures (i.e., fence
building), can be a quick (1–2 years) and effective method for improving and safeguarding the diversity of dune plant communities. 相似文献
220.
Community-based collaborative groups involved in public natural resource management are assuming greater roles in planning,
project implementation, and monitoring. This entails the capacity of collaborative groups to develop and sustain new organizational
structures, processes, and strategies, yet there is a lack of understanding what constitutes collaborative capacity. In this
paper, we present a framework for assessing collaborative capacities associated with community-based public forest management
in the US. The framework is inductively derived from case study research and observations of 30 federal forest-related collaborative
efforts. Categories were cross-referenced with literature on collaboration across a variety of contexts. The framework focuses
on six arenas of collaborative action: (1) organizing, (2) learning, (3) deciding, (4) acting, (5) evaluating, and (6) legitimizing.
Within each arena are capacities expressed through three levels of social agency: individuals, the collaborative group itself,
and participating or external organizations. The framework provides a language and set of organizing principles for understanding
and assessing collaborative capacity in the context of community-based public forest management. The framework allows groups
to assess what capacities they already have and what more is needed. It also provides a way for organizations supporting collaboratives
to target investments in building and sustaining their collaborative capacities. The framework can be used by researchers
as a set of independent variables against which to measure collaborative outcomes across a large population of collaborative
efforts. 相似文献