Feasibility of a single-species quota system for management of the Malaysian multispecies purse-seine fishery

Malaysian fisheries employ multiple measures to improve management; however, not all are well-suited to the multispecies fisheries. As part of a pilot project, an individual quota system was introduced for the purse-seine fishery off the East Coast of Peninsular Malaysia (ECPM), but no assessment of this particular measure nor the feasibly of its implementation has been confirmed. Therefore, this study analysed spatial and temporal patterns of purse-seine fishing, by collecting catch composition data per landing and its fishing ground within three period fishery surveys between August 2017 and September 2018 at six different landing sites. Similarity and cluster analysis examined species composition and diversity to determine the feasibility of implementing a single-species quota system in this multispecies fishery. Some overlapped of indices results and minor difference in catch composition were found due to changes in spatial and temporal fishing activities. However, no specific spatial or temporal patterns were discernible as structuring the fishing grounds used by purse-seiners. The absence of patterns, using the available data, might be attributable to huge species aggregations and widely distributed and homogenously mixed fish stocks. Thus, it is likely impractical to manage species individually in such a multispecies fishery.     

Biomass of a man-made forest of timber tree species in the humid tropics of West Java, Indonesia

Biomass of a mature man-made forest in West Java, Indonesia, was estimated to evaluate the carbon sequestration potential of plantation forest in the humid tropics. Twenty plots, each 0.25 ha in area and containing one to six planted species over 40 years of age and with closed canopies, were selected. Trunk dry mass was estimated from trunk diameter, tree height, and bulk density. Maximum trunk diameter (122 cm) was observed in a 46-year-old Khaya grandifoliola C. DC. tree, and the tallest tree (51 m) was a 46-year-old Shorea selanica (DC.) Blume. The largest trunk biomass (911 Mg ha⁻¹) was achieved in the plot composed of two Khaya spp. Among the plots composed of indigeneous Dipterocarpaceae species, the largest trunk biomass was 635 Mg ha⁻¹. These trunk biomasses were larger than those reported from primary rainforests in Southeast Asia (e.g., 403 Mg ha⁻¹ in East Kalimantan, 522 and 368 Mg ha⁻¹ in Peninsular Malaysia). The large biomass in this forest suggests that, given favorable conditions, man-made forests can accumulate the quantities of atmospheric carbon that were lost by the logging of primary forests in the humid tropics.     

The spleen morphophysiology of fruit bats

Spleen is one of the important lymphoid organs with wide variations of morphological and physiological functions according to species. Morphology and function of the spleen in bats, which are hosts to several viral strains without exhibiting clinical symptoms, remain to be fully elucidated. This study aims to examine the spleen morphology of fruit bats associated with their physiological functions. Spleen histological observations were performed in three fruit bats species: Cynopterus titthaecheilus (n = 9), Rousettus leschenaultii (n = 3) and Pteropus vampyrus (n = 3). The spleens of these fruit bats were surrounded by a thin capsule. Red pulp consisted of splenic cord and wide vascular space filled with blood. Ellipsoids in all three studied species were found numerously and adjacent to one another forming macrophages aggregates. White pulp consisted of periarteriolar lymphoid sheaths (PALS), lymphoid follicles and marginal zone. The lymphoid follicle contained a germinal centre and a tingible body macrophage that might reflect an active immune system. The marginal zone was prominent and well developed. This study reports some differences in spleen structure of fruit bats compared to other bat species previously reported and discusses possible physiological implications of the spleen based on its morphology.     

Precondition for Integration: In Support of Stand-alone Social Science in Rangeland and Silvopastoral Research

Most agree that social and ecological approaches should be integrated to ensure sustainable management of natural resources. However, an analysis of the content of three problem-based journals shows that if social sciences are included at all, they are typically subservient to natural sciences, and that quantitative approaches are privileged. We argue that true integration is achievable only if natural sciences and social sciences are each robust and if they meet eye to eye. We call for more openness to stand-alone social science research in problem-based journals, especially to research using qualitative methods. We highlight the potential insights derived from studying decision makers at the microlevel: the pastoralists, farmers, ranchers, and foresters who make final management choices. We argue that publishing such qualitative social sciences promotes dialogue across disciplines, strengthens integration, and increases the real-world impact of research.     

Soil organic‐matter stocks and characteristics along an Alpine elevation gradient

Mountain regions are known to be especially vulnerable to climatic changes; however, information on the climate sensitivity of alpine ecosystems is still scarce to date. In this study, we investigate the impacts of climate and vegetation composition on soil organic‐matter (SOM) stocks and characteristics along an elevation gradient (900 to 1900 m asl) in the Austrian Limestone Alps. The soils classified as Leptic Histosols, i.e., organic soils directly overlying the calcareous bedrock. Soil organic‐carbon stocks (SOC; mean ± standard deviation) to bedrock increased in the low‐elevation forest sites from 19 ± 3 kg m^–2 (900 m asl) to 31 ± 3 kg m^–2 (1300 m asl), reached a maximum (38 ± 5 kg m^–2) in the shrubland at 1500 m asl, but decreased again in the high‐elevation grassland sites (26 ± 3 kg m^–2 at 1700 m asl and 13 ± 3 kg m^–2 at 1900 m asl). Thermogravimetic measurements and Fourier‐transform infrared spectroscopy (FTIR) suggest that the upper soil layers were dominated by more labile organic compounds, whereas more persistent materials increased with depth. Along the studied climosequence, the aliphatic FTIR band (2920 cm^–1) was lower in the low‐elevation forest sites compared to the high‐elevation grassland sites. Most other FTIR bands did not change with altitude, but were related to specific site conditions, such as vegetation composition and associated differences in soil pH. Our results demonstrate that differences in SOM stocks and characteristics are not consistently related to variations in climatic conditions along the studied elevation gradient, but are strongly affected by the vegetation composition, their C input and litter quality. This, in turn, is expected to shift in response to climate change.     

Converting or not converting to organic farming in Austria:Farmer types and their rationale

Reasons for converting to organic farming have been studied in a number of instances. However, the underlying rationale that motivates the behavior is not always made clear. This study aims to provide a detailed picture of farmers decision-making and illustrate the choice between organic and conventional farm management. Based on 21 interviews with farmers, a decision-tree highlighting the reasons and constraints involved in the decision of farmers to use, or not to use, organic production techniques was formulated. The accuracy of the decision-tree was tested through a written survey of 65 randomly sampled farmers. The decision-tree permits the identification of decision criteria and examines the decision-making process of farmers in choosing their farming method. It also allows for the characterization of farmer strategies and values, identifying five types of farmers: the committed conventional; the pragmatic conventional; the environment-conscious but not organic; the pragmatic organic; and the committed organic. The importance of taking into account heterogeneity in farmers attitudes, preferences, and goals and their impact on the choice of a farming method is emphasized.Ika Darnhofer is an Assistant Professor at the Institute of Agricultural and Forestry Economics at the University of Natural Resources and Applied Life Sciences Vienna. She received both her MSc and PhD in Agricultural Economics from the University of Natural Resources and Applied Life Sciences Vienna, working on issues of agricultural development in Africa. Her current research interests include economic and sociological analyses of factors that shape farmers land use decision-making behavior, with a particular focus on organic farming.Walter Schneeberger is a Full Professor of Farm Business Management and Head of the Institute of Agricultural and Forestry Economics at the University of Natural Resources and Applied Life Sciences Vienna. His current research interests include the economics of producing and processing agricultural products and farm business management for both conventional and organic farms.Bernhard Freyer is a Full Professor of Organic Farming and Head of the Institute of Organic Farming of the University of Natural Resources and Applied Life Sciences Vienna. His work on organic farming focuses on its agronomic aspects (plant cultivation, crop rotations, and soil fertility) as well as on the analysis of conversion to organic farming (planning process, farm development) and its potential for regional development.     

Neutralization of acidic groundwater inputs and control of metal mobility by a near-shore adirondack lake sediment

Biogeochemical processes contributing to the neutralization of acidic groundwater passing through near-shore sediments of an acidified lake (Dart's Lake) were investigated in a controlled laboratory experiment. Three intact sediment cores collected from the near-shore region of the lake were connected to a system that simulated groundwater flow through lake sediments in a temperature controlled laboratory environment. The effect of sediment biogeochemical processes on groundwater chemistry was determined by evaluating changes in acid/base and metal chemistry for solutions entering and leaving the cores. Aluminum mobilization represented the most significant source of neutralization for each core and contributed up to 99% of H⁺ removal. Although the sediment cores were collected parallel to the shoreline and over a linear distance of only 0.3 m, significant differences in sediment chemistry were apparent and contributed to variations in the chemistry of water transported from the cores. For one core that exhibited retention of Al from the influent groundwater, retention of Pb by the sediment was similarly observed. Following acidification of this groundwater, Pb was readily remobilized. These results suggest that near-shore lake sediments may be effective at influencing seasonal variations in Al, Pb and base cations in lakes receiving groundwater inputs.     

Morphological characterization of Horsfield’s treeshrew Tupaia javanica lingual papillae: Light microscopy and scanning electron microscopy studies

The Horsfield's treeshrew (Tupaia javanica) is one of the shrews found on the island of Java that mainly feeds on fruits and occasionally insects. This shrew has an important role in the ecosystem as it spreads plant seeds and controls insects. To this day, there is no available knowledge about the structure of Horsfield's treeshrew's tongue. Therefore, the aim of this study was to provide data on the tongue structure of the Horsfield's treeshrew through two different methods. We investigated the tongue morphology and lingual papillae distribution of Tupaia javanica using 1) scanning electron microscopy (SEM) for microscopic structure and 2) histology for microscopic organization. Our macroscopic results revealed that the tongue of Tupaia javanica can be divided into three parts: apex, corpus and radix. The dorsal surface of the medial corpus is the median groove extending to the radix. Observation using SEM and light microscopy (LM) showed that the apex of the tongue bears three types of papillae: scale-like filiform, small filiform and fungiform. These are rosette filiform papillae, cornflower filiform papillae, conical papillae and fungiform papillae in the corpus. Meanwhile, the radix contains small filiform papillae, scale-like filiform papillae, vallate papillae, conical papillae and fungiform papillae. On the lateral posterior radix, Weber's gland reacts positively to PAS reaction. Taking together, our research shows that there are variations in the papillae on the tongue surface of Horsfield's treeshrew, and the variations of these papillae are very dependent on the pattern, type of food and the function of the tongue.     

Microbial community composition and activity in different Alpine vegetation zones

In alpine environments, climate change may alter vegetation composition as well as the quantity and quality of plant litter, which in turn may affect microbial community composition and functioning. In this study, we analyzed soil microbial community composition and its activity along a vegetation gradient (900-1900 m above sea level (a.s.l.)) in the Austrian Limestone Alps. Soil pH and C:N ratios were significantly different under different plant communities and ranged from 3.9 to 6.1 and from 29 to 17, respectively. The highest amounts of microbial biomass, estimated by the sum of microbial phospholipid fatty acids (total PLFAs), were found at sites with high pH and low C:N ratio, i.e. in alpine grassland and beech forest sites (3.9 ± 0.05 and 3.4 ± 0.7 μmol per g organic carbon (OC), respectively), and the lowest amounts were found at sites with low pH and high C:N ratio, i.e. sites with high percentage of conifers and acidophilic vegetation (around 2 μmol (g OC)⁻¹). Total and bacterial PLFAs as well as microbial activity (dimethyl sulphoxide reduction) did not show consistent altitudinal trends. The fungal PLFA 18:2ω6,9 was significantly higher in the forest sites (between 9.2 and 6.7 mol%) compared to the shrubland and grassland sites (between 4.5 and 2.3 mol%). A similar trend was found for ergosterol contents. As a consequence, the bacterial to fungal biomass ratio increased significantly from forest sites to shrubland and grassland sites. Expected future upward migration of the tree line in alpine environments in response to climate warming will therefore increase the abundance of fungi in these ecosystems.     

Viral-derived DNA invasion and individual variation in an Indonesian population of large flying fox Pteropus vampyrus

Here, we performed next-generation sequencing (NGS) on six large flying foxes (Pteropus vampyrus) collected in Indonesia. Seventy-five virus species in the liver tissue of each specimen were listed. Viral homologous sequences in the bat genome were identified from the listed viruses. This finding provides collateral evidence of viral endogenization into the host genome. We found that two of the six specimens bore partial sequences that were homologous to the plant pathogens Geminiviridae and Luteoviridae. These sequences were absent in the P. vampyrus chromosomal sequences. Hence, plant viral homologous sequences were localized to the hepatocytes as extrachromosomal DNA fragments. Therefore, this suggests that the bat is a potential carrier or vector of plant viruses. The present investigation on wild animals offered novel perspectives on viral invasion, variation, and host interaction.