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A Laboratory outbreak investigation of Post-Monsoon Endemic Moist Eczematous Syndrome in cattle in Jhapa District of Nepal
Kedar Karki,Poornima Manandhar and Pragya Koirala
Veterinary World , 2008,
Abstract: An endemic hyperemic moist eczematous syndrome was reported in Cattle and Buffaloes in Jhapa district of Nepal during month of September after prolong spell of drought followed by heavy rainfall causing water logging total 56 cattle and buffalo were affected and out of which 12 animal died. Rest of ill animals were treated with 5%of Antidegnala liquor and Penta-sulphate. Straw and Skin samples revealed Penicillium sp.Fungus.After long spell of drought period followed by repeated flooding in lowland area in tropical and subtropical there is likely increase risk of fungal infestation in forage fed to cattle buffaloes seems to be risky for occurence of Endemic Moist Eczamztous syndrome, either preventive measure for its prevention or early treatment with either with anti Degnala liquor or Use of pentasulphate seem to prevent loss from this condition. [Veterinary World 2008; 1(8.000): 233-236]
Development of Allometric Equations for Estimating Above-Ground Liana Biomass in Tropical Primary and Secondary Forests, Malaysia  [PDF]
Patrick Addo-Fordjour,Zakaria B. Rahmad
International Journal of Ecology , 2013, DOI: 10.1155/2013/658140
Abstract: The study developed allometric equations for estimating liana stem and total above-ground biomass in primary and secondary forests in the Penang National Park, Penang, Malaysia. Using biomass-diameter-length data of 60 liana individuals representing 15 species, allometric equations were developed for liana stem biomass and total above-ground biomass (TAGB). Three types of allometric equations were developed: models fitted to untransformed, weighted, and log-transformed (log10) data. There was a significant linear relationship between biomass and the predictors (diameter, length, and/or their combinations). The same set of models was developed for primary and secondary forests due to absence of differences in regression line slopes of the forests (ANCOVA: ). The coefficients of determination values of the models were high (stem: 0.861 to 0.990; TAGB: 0.900 to 0.992). Generally, log-transformed models showed better fit (Furnival's index, FI < 0.50) than the other models (FI > 0.5). A comparison of the best TAGB model in this study (based on FI) with previously published equations indicated that most of the equations significantly ( ) overestimated TAGB of lianas. However, a previous equation from Southeast Asia estimated TAGB similar to that of the current equation ( ). Therefore, regional or intracontinental equations should be preferred to intercontinental equations when estimating liana biomass. 1. Introduction Lianas have great influence on forest ecosystems, especially in tropical forests [1]. They contribute very much to species diversity in the tropics, constituting as high as 38% of species diversity [2]. They may compose of a much higher percentage (45%) with regard to total woody plant stems in the tropics (cf. [3]). Lianas serve as an important source of food for forest fauna especially in the dry season [4]. They may provide up to about one-third of canopy foliage in the forest (cf. [5]) and therefore contribute substantially (up to 36%) to total above-ground leaf biomass in tropical forest ecosystems [6]. Lianas compete with trees which may affect tree growth [7, 8]. Additionally, they may have negative influence on seed production of trees and also impede natural regeneration of trees [7–9]. Tropical forest ecosystems continue to be exploited at alarming rates resulting in their conversion to secondary forests and many other forms of land use [10]. A high proportion of forests in the tropics is made up of secondary forests [11]. In Malaysia, many lowland dipterocarp forests have been converted to secondary forests as a result of logging,
How Ebola Impacts Genetics of Western Lowland Gorilla Populations  [PDF]
Pascaline J. Le Gouar,Dominique Vallet,Laetitia David,Magdalena Bermejo,Sylvain Gatti,Florence Levréro,Eric J. Petit,Nelly Ménard
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0008375
Abstract: Emerging infectious diseases in wildlife are major threats for both human health and biodiversity conservation. Infectious diseases can have serious consequences for the genetic diversity of populations, which could enhance the species' extinction probability. The Ebola epizootic in western and central Africa induced more than 90% mortality in Western lowland gorilla population. Although mortality rates are very high, the impacts of Ebola on genetic diversity of Western lowland gorilla have never been assessed.
Predation by Corallus annulatus (Boidae) on Rhynchonycteris naso (Emballonuridae) in a lowland tropical wet forest, Costa Rica
Lewis, Todd R.,Nash, Darryn J.,Grant, Paul B. C.
Cuadernos de Herpetología , 2009,
Abstract: Corallus annulatus (Northern Annulated Tree-boa) is a little-studied tropical Boid occurring disjunctively throughout Central America and tropical South America in mostly lowland tropical moist and wet forests (Holdridge, 1967; Stafford & Henderson, 1996; Smith & Acevedo, 1997; Henderson et al., 2001). Prior to this report and to the best of our knowledge, small rodents were the only documented prey for wild specimens of C. annulatus (Henderson et al., 1995). Ca o Palma Biological Station is situated on the northeast coast of Costa Rica approximately 8 km north of Tortuguero. C. annulatus has previously been recorded from Manicaria forest at Ca o Palma (Myers, 1990; Burger, 2001). On 12th January 2002 and 15th July 2003 we found two separate C. annulatus specimens with Rhynchonycteris naso (Proboscis bat) in their stomachs.
The Mechanics of Gross Moist Stability
David James Raymond,Sharon Sessions,Adam Sobel,Zeljka Fuchs
Journal of Advances in Modeling Earth Systems , 2009, DOI: 10.3894/james.2009.1.9
Abstract: The gross moist stability relates the net lateral outflow of moist entropy or moist static energy from an atmospheric convective region to some measure of the strength of the convection in that region. If the gross moist stability can be predicted as a function of the local environmental conditions, then it becomes the key element in understanding how convection is controlled by the large-scale flow. This paper provides a guide to the various ways in which the gross moist stability is defined and the subtleties of its calculation from observations and models. Various theories for the determination of the gross moist stability are presented and its roles in current conceptual models for the tropical atmospheric circulation are analyzed. The possible effect of negative gross moist stability on the development and dynamics of tropical disturbances is currently of great interest.
Liana Abundance, Diversity, and Distribution on Barro Colorado Island, Panama  [PDF]
Stefan A. Schnitzer, Scott A. Mangan, James W. Dalling, Claire A. Baldeck, Stephen P. Hubbell, Alicia Ledo, Helene Muller-Landau, Michael F. Tobin, Salomon Aguilar, David Brassfield, Andres Hernandez, Suzanne Lao, Rolando Perez, Oldemar Valdes, Suzanne Rutishauser Yorke
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0052114
Abstract: Lianas are a key component of tropical forests; however, most surveys are too small to accurately quantify liana community composition, diversity, abundance, and spatial distribution – critical components for measuring the contribution of lianas to forest processes. In 2007, we tagged, mapped, measured the diameter, and identified all lianas ≥1 cm rooted in a 50-ha plot on Barro Colorado Island, Panama (BCI). We calculated liana density, basal area, and species richness for both independently rooted lianas and all rooted liana stems (genets plus clones). We compared spatial aggregation patterns of liana and tree species, and among liana species that varied in the amount of clonal reproduction. We also tested whether liana and tree densities have increased on BCI compared to surveys conducted 30-years earlier. This study represents the most comprehensive spatially contiguous sampling of lianas ever conducted and, over the 50 ha area, we found 67,447 rooted liana stems comprising 162 species. Rooted lianas composed nearly 25% of the woody stems (trees and lianas), 35% of woody species richness, and 3% of woody basal area. Lianas were spatially aggregated within the 50-ha plot and the liana species with the highest proportion of clonal stems more spatially aggregated than the least clonal species, possibly indicating clonal stem recruitment following canopy disturbance. Over the past 30 years, liana density increased by 75% for stems ≥1 cm diameter and nearly 140% for stems ≥5 cm diameter, while tree density on BCI decreased 11.5%; a finding consistent with other neotropical forests. Our data confirm that lianas contribute substantially to tropical forest stem density and diversity, they have highly clumped distributions that appear to be driven by clonal stem recruitment into treefall gaps, and they are increasing relative to trees, thus indicating that lianas will play a greater role in the future dynamics of BCI and other neotropical forests.
Impacts of Cloud-Induced Mass Forcing on the Development of Moist Potential Vorticity Anomaly During Torrential Rains
GAO Shouting,ZHOU Yushu,CUI Xiaopeng,DAI Guoping,
GAO Shouting
,ZHOU Yushu,CUI Xiaopeng,DAI Guoping

大气科学进展 , 2004,
Abstract: The impacts of cloud-induced mass forcing on the development of the moist potential vorticity (MPV)anomaly associated with torrential rains are investigated by using NCEP/NCAR 1°× 1° data. The MPV tendency equation with the cloud-induced mass forcing is derived, and applied to the torrential rain event over the Changjiang River-Huaihe River Valleys during 26-30 June 1999. The result shows that positive anomalies are located mainly between 850 hPa and 500 hPa, while the maximum MPV, maximum positive tendency of the MPV, and maximum surface rainfall are nearly collocated. The cloud-induced mass forcing contributes to the positive tendency of the moist potential vorticity anomaly. The results indicate that the MPV may be used to track the propagation of rain systems for operational applications.
Factors Influencing Liana Species Richness and Structure following Anthropogenic Disturbance in a Tropical Forest, Ghana  [PDF]
Patrick Addo-Fordjour,Philip El Duah,David Kafui Kudjo Agbesi
ISRN Forestry , 2013, DOI: 10.1155/2013/920370
Abstract: The study was conducted to determine the factors that influenced liana species richness and structure in forests of different disturbance intensities (high, moderate, and low disturbance forests) in the Southern Scarp Forest Reserve, Ghana. Within each forest, lianas (dbh ?cm) were enumerated in six ?m2 plots located along transects. Soil physicochemical properties and forest structure were determined within the plots. Liana species richness and abundance were significantly lower in the high disturbance forest ( ) whereas basal area was significantly higher in the low disturbance forest ( ). Tree abundance and dbh significantly predicted liana species richness and structure in the study ( ). On the basis of the importance value index, three main liana communities, each corresponding with a forest type, were identified. Stepwise multiple regression analysis revealed that exchangeable magnesium and calcium, and total exchangeable bases were the main soil variables that affected liana species richness. Liana structure was influenced by the above-mentioned soil variables as well as exchangeable potassium and sodium, and pH. The present study has demonstrated that changes in liana species richness and structure following human disturbance may be due to variations in soil properties and forest structure. 1. Introduction Lianas are woody climbers that are rooted in the soil and climb other plants to the reach forest canopy [1]. They have significant influence on forest ecology and ecosystem function, particularly in tropical forests (cf. [2]). For instance, they help to stabilise the microclimate of the forest floor by forming a mass of leafy vegetation to close canopy gaps [3]. Lianas may help maintain tree diversity in the forest by causing tree falls which could reduce the dominance of tree species [4]. Heavy liana loads on trees can cause mechanical damage of the hosts and also reduce their growth rates [5, 6]. Additionally, lianas could impact negatively on natural regeneration of trees in forest ecosystems [7]. In the light of recent reports of increasing liana abundance in tropical forests [8–14], lianas could modify forest ecosystems through their influence on tree regeneration and growth. Understanding the factors that govern liana community assembly in tropical forests is therefore of utmost priority, and necessary in developing forest conservation strategies. Human disturbance has been identified as one of the main drivers of liana success in tropical forest ecosystems [3, 4, 11, 15, 16]. Both patterns of increasing and decreasing liana diversity
Socio-Economic Analysis of the Operational Impacts of Shiroro Hydropower Generation in the Lowland Areas of Middle River Niger  [PDF]
Abdullateef Usman,I. P. Ifabiyi
International Journal of Academic Research in Business and Social Sciences , 2012,
Abstract: This study focused on the socio-economic analysis of the operational impacts of Shiroro hydroelectric power generation dam in the lowland areas of middle river Niger in Nigeria. The paper observed that more than thirty years since the conception and impoundment of water at Kanji over river Niger a number of action or inaction capable of altering the socio-economic profile of the riparian communities around the lowland areas of middle river Niger in Nigeria have taken place. The study therefore designed and administered a close-ended pre-coded instrument to conduct a survey of the dam affected communities located in the study area. The data harvested were analyzed using the Principal Component Analysis (PCA). The result obtained shows that the economic engagements of the riparian communities have been distorted. This is noticeable especially on both fish biodiversity and ecosystem with a resultant loss of fish-species. There is a dismal fall in productivity of small holder farmers and fishermen occasioned by avoidable flooding. In the same vein Strategic social and economic infrastructure have deteriorated and thus slowed down the socio and economic development in the area. In this connection a number of policy measures to mitigate the negative effect of hydropower production were suggested.
Mixed Species Allometric Models for Estimating above-Ground Liana Biomass in Tropical Primary and Secondary Forests, Ghana  [PDF]
Patrick Addo-Fordjour,Zakaria B. Rahmad
ISRN Forestry , 2013, DOI: 10.1155/2013/153587
Abstract: The study developed allometric models for estimating liana stem and total above-ground (TAGB) biomass in primary and secondary forests in the Asenanyo Forest Reserve, Ghana. Liana biomass was determined for 50 individuals for each forest using destructive sampling. Various predictors involving liana diameter and length were run against liana biomass in regression analysis, and , RMSE, and Furnival's index of fit (FI) were used for model comparison. The equations comprised models fitted to untransformed and log-transformed data. Forest type had a significant influence ( ) on liana allometric models in the current study, resulting in the development of forest-type-specific equations. There were significant and strong linear relationships between liana biomass and the predictors in both forests ( ). Liana diameter was a better predictor of biomass than liana length. Generally, the models which were based on log-transformed data showed better fit (higher FI values) than those fitted to untransformed data. Comparison of the site specific models in the current study with previously published models indicated that the models of the current study differed from the previous ones. This indicates the need for forest specific equations to be used for accurate determination of above-ground liana biomass. 1. Introduction Lianas are important structural component of tropical forests [1]. They perform a number of ecological functions which help to sustain tropical forest ecosystems [2]. Lianas add substantially to plant assemblages in tropical forests in terms of number of species [3] and stem density [4]. Apart from contributing directly to species diversity in tropical forests, lianas also play a number of roles which contribute to maintain diversity of other organism [5]. Due to relatively high dominance of lianas in tropical forests, they also contribute a lot to forest biomass, especially in heavy liana infested forests. Specifically, lianas can accumulate as high as 30% of total above-ground biomass in tropical forest ecosystems [2]. Comparatively, lianas devote much less biomass for stem support than tress, and therefore, they are able to allocate more biomass for their growth compared with trees [2, 5]. Consequently, lianas have higher biomass growth than trees [6]. Lianas allocate more biomass for leaf production than the amount of biomass allocated to their stems. Because lianas allocate less biomass to their stems they produce less dense wood compared to trees [7]. Estimating tropical forest biomass and determining its dynamics are important aspects of
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