1,720,966 research outputs found
Comparing NDVI and Corine Land Cover as Tools for Improving National Forest Inventory Updates and Preventing Illegal Logging in Serbia
Full text linkNational forest inventories (NFIs) in Serbia have been carried out very rarely (every 20
years), while the last two official estimates of forest areas (for 2011 and 2014) are very
imprecise, because they are based on the cadastral data (and Serbia is well known for the
lack of cadastre updating). Although forest conservation policymakers in Serbia still have
limited financial, human, and political resources, over the past two decades, publicly
available, remotely sensed satellite data on deforestation and degradation have dramatically
reduced
evaluation
costs.
Since
municipalities
in
Southern
Serbia
experienced
a
15%
loss
of
forest
area
in
the
2006–2014
period,
as
the
obvious
result
of
forceful,
rapid
process
of
illegal
logging,
this
study
evaluates
the
possible
use
of
two
remote
sensing
techniques:
normalized
difference
vegetation
index
(NDVI)
and
CORINE
land
cover
(CLC)
databases
for
preventing
illegal
logging
in
Serbia.
It
clearly
shows
that
NDVI
is
very
promising
for
Serbia
and
also
for
other
post-socialist
countries
that
very
rarely
carry
out
national
forest
inventories
(NFIs), and where unrecorded, illegal logging can exceed the legal harvest
by a factor of 10
Vegetation Structure and Prioritizing Plants for Eco-Restoration of Degraded Wildlife Corridor in Dry Tropical Forest of South India
Full text linkWildlife corridors are critical to manage wildlife and maintain ecological processes. However, they are fragmented and degraded due to various anthropogenic activities.
Fragmentation in turn affects population viability of species by affecting their dispersal, re-colonization and genetic exchanges. But the process can be reversed through restoration and management of ‘functional corridors’. So far in the forestry sector, monoculture plantations are known to be the ideal reforestation/afforestation strategy to restore degraded landscape but experts argue that monoculture plantations have failed to recover former biological diversity. Therefore, for successful eco-restoration, first, the regional plant stock has to be identified and then suitable plant species have to be prioritized. The habitat enrichment through assisted vegetation method in the degraded wildlife
corridors can improve green cover and also bring back the original vegetation. The study was conducted in the Edeyarahalli-Doddasampige wildlife corridor area, which is
part of Biligiri Rangaswamy Temple Tiger Reserve, Western Ghats, India. The vegetation was enumerated through transect and quadrate method. The vegetation structure was
analyzed and ten suitable native plant species were prioritized for eco-restoration. The priority was given based on site condition and socio-ecological importance of the plants such as trees with timber value, non-timber forest products, nectar source for honey bees and also food source for elephants. At a time of unprecedented forest destruction, the interventions made through this line of research would not only improve the habitat
quality but also increase the functionality of wildlife corridors by providing safe passage for animals’ movement. In addition to this, convergence of local multistakeholders and their responsibility needs to be explored toward eco-restoration process
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Within-plant variation in defences in response to simulated herbivory in a semi-arid Southern African Savannah
No full textThis is an article,Within-plant spatial variation in herbivore pressure can induce localized antiherbivory defence responses. We tested this hypothesis by studying branch-specific responses of Acacia robusta, Dichrostachys cinerea and
Ziziphus mucronata to simulated mammalian herbivory. Herbivory was simulated by clipping the terminal shoots(3 cm from tip) of tree branchlets, allowing them one year
of regrowth and then comparing their spine length and density and condensed tannins with those of adjacen tunclipped branchlets. Condensed tannin concentrations were higher in clipped branchlets than in unclipped
branchlets in all three woody species (P < 0.05). Spine length was higher in clipped branchlets than in unclipped branchlets in A. robusta (P < 0.05) but was similar in both
D. cinerea and Z. mucronata (P > 0.05). Spine density was double in clipped branchlets as compared to the unclipped branchlets in Z. mucronata (P < 0.05) but was similar in
both A. robusta and D. cinerea (P > 0.05). We found evidence of within-plant variation in condensed tannins concentration and spine length and density in response to simulated herbivory in the three woody species.,International Foundation for Science, Stockholm, Sweden, through research grant D/4149-2
Effects of supplementing natural pasture hay with five Calliandra calothyrsus Provenances on the intake, digestibility, nitrogen balance and excretion of purine derivatives by goats.
No full textPublished Article,Forty indigenous castrated goats with a body weight of
20.03 ± 0.97 kg were used in a nitrogen balance trial to
investigate the effects of supplementing natural
pasture hay with five provenances of C. calothyrsus on
the intake, digestibility, nitrogen balance and excretion
of purine derivatives by goats. The goats were
assigned to five treatment diets with each provenance
at two levels (100g/day and 200g/day) of
supplementation in a completely randomized design.
Provenance and level of supplementation had a
significant effect (P<0.05) on intake of basal diet,
supplement, total dry matter and total organic matter
intake, while there was no interaction between the
provenance and the level of supplement. The nitrogen
balance was similar in provenances OFI 9/89 and
12/91 at 100 g/d supplementation, while at 200 g/d
supplementation the nitrogen balance was similar
between provenances OFI 9/89 and 10/91 and between
OFI 12/91 and 62/91. The microbial protein yield was
similar between provenances OFI 9/89, OFI 10/91 and
62/91 at 100 g/d supplementation, while at 200 g/d
supplementation provenance OFI 9/89 was similar to
OFI 12/91 and OFI 23/91 similar to OFI 62/91. On the
basis of total dry matter intake at 100 g/day
supplementation OFI 23/91 had the highest intake with
OFI 10/91 having the lowest. This trend seemed to be
reversed at 200 g/day supplementation with OFI 10/91
having the highest intake and OFI 23/91 having the
least intake. Provenance OFI 12/91 had the highest
microbial protein yield while OFI 23/91 had the
lowest. While this study clearly shows that the five
provenances had different effects in goat nitrogen
metabolism no clear trend of superiority could be
established
Effects of supplementing native pasture hay with puncture vine (Tribulus terrestris) on the intake, weight change, nitrogen balance and excretion of purine derivatives of sheep.
No full textPublished Article.,Eight male sheep (average 34.17 ± 3.33 kg LW) were
used in a nitrogen balance trial to measure dry matter
intake, weight change, nitrogen balance and microbial
protein yield. A completely randomized design was
used and the animals were randomly allocated to the
two treatment diets. The sheep were given a) native
pasture hay (NPH) + 100 g crushed maize (CM
)(control diet) or b) NPH + 100 g CM + 160 g Tribulus
terrestris. The native pasture hay comprised of a
mixture of grasses with Heteropogon contortus,
Eragrostis rigidiour and E. superba being
predominant and had a crude protein content of 37.5
g/kg DM. The puncture vine was harvested at the
onset of flowering, dried and graded to remove large
stems and woody fruits. The total feed intake (918.14
g/d) of sheep given T. terrestris supplement was
significantly (P< 0.05) higher than that of the control
diet (553.70 g/d). T. terrestris supplementation also
resulted in an average weight gain of 38.13 g/d while
on the control diet an average loss of 130.43 g/d was
recorded. Puncture vine supplementation also resulted
in higher nitrogen retention (2.30 g/d) as compared to
the control diet (0.43 g/d). Microbial protein yield was
16.48 g/d with puncture vine supplementation and 6.39
g/d for the control diet. The results show that the
inclusion of T. terrestris as a protein supplement to
low quality natural pasture hay diets increases dry
matter intake, nitrogen balance and microbial protein
yield
Response of three Acacia species to simulated herbivory in a semi-arid southern African savanna.
No full textPublished Article.,This study investigated responses of juvenile Acacia karroo,
Acacia nilotica and Acacia rehmanniana to simulated herbivory
in a semi-arid southern African savanna. For each
species, we clipped twigs in the dry season and measured
the removed twig biomass. Seven months after clipping, we
counted the number of resprouts on clipped stems and
measured their lengths, diameters and biomass. We also
measured dieback length on clipped stems and dieback
biomass (DB). Removed twigs of A. rehmanniana had the
greatest biomass, followed by A. karroo and least was
A. nilotica. However, A. nilotica had the greatest resprout
biomass, followed by A. rehmanniana and least was
A. karroo. Consideration of DB as lost biomass resulted in
A. karroo fully compensating lost biomass, A. nilotica overcompensating
and A. rehmanniana under-compensating.
Acacia rehmanniana had the shortest resprouts while
A. nilotica had the longest. The number and the diameter of
resprouts did not vary among the species. We conclude by
predicting that in semi-arid African savannas, undercompensation
has the greatest probability of occurrence
among woody species prone to severe shoot dieback following
herbivory
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