An inventory of Guadua (Guadua angustifolia) bamboo in the Coffee Region of Colombia

Management of renewable natural resources and the corresponding policy formulation should be founded on reliable data and information. This refers both to information on the resource itself and to information on the market situation. In this paper, we present methodology and major results of an inventory of the Guadua resources, in a study area of about 1 million ha within the Coffee Region of Colombia. This inventory produced for the first time sample-based statistical estimations of the Guadua area and growing stock. In the study area, land cover of Guadua patches was estimated to be 3.9% or about 40,000 ha (minimum patch area 0.3 ha). This is higher than figures published earlier. Estimation for mean number of standing culms (including shoots and dry culms) per hectare was 6,940 with a mean diameter at breast height of 10.8 cm, apparent commercial volume of 654 m3/ha, commercial wood volume of 304 m3/ha, oven-dry biomass of 311 ton/ha, and total carbon stock of 156 ton/ha. While the low-intensity sampling approach worked well and may serve as an example for similar studies, we identified a number of issues for further research, particularly in what refers to as the basic mensurational models for Guadua volume and biomass estimation from inventories.     

Drinking water sources,availability, quality,access and utilization for goats in the Karak Governorate,Jordan

Goat production is an important agricultural activity in Jordan. The country is one of the poorest countries in the world in terms of water scarcity. Provision of sufficient quantity of good quality drinking water is important for goats to maintain feed intake and production. This study aimed to evaluate the seasonal availability and quality of goats’ drinking water sources, accessibility, and utilization in different zones in the Karak Governorate in southern Jordan. Data collection methods comprised interviews with purposively selected farmers and quality assessment of water sources. The provision of drinking water was considered as one of the major constraints for goat production, particularly during the dry season (DS). Long travel distances to the water sources, waiting time at watering points, and high fuel and labor costs were the key reasons associated with the problem. All the values of water quality (WQ) parameters were within acceptable limits of the guidelines for livestock drinking WQ with exception of iron, which showed slightly elevated concentration in one borehole source in the DS. These findings show that water shortage is an important problem leading to consequences for goat keepers. To alleviate the water shortage constraint and in view of the depleted groundwater sources, alternative water sources at reasonable distance have to be tapped and monitored for water quality and more efficient use of rainwater harvesting systems in the study area is recommended.

     

Detection of ruminant meat and bone meals in animal feed by real-time polymerase chain reaction: result of an interlaboratory study

The commercialization of animal feeds infected by prions proved to be the main cause of transmission of bovine spongiform encephalopathy (BSE). Therefore, feed bans were enforced, initially for ruminant feeds, and later for all feeds for farmed animals. The development and validation of analytical methods for the species-specific detection of animal proteins in animal feed has been indicated in the TSE (Transmissible Spongiform Encephalopathies) Roadmap (European Commission. The TSE (Transmissible Spongiform Encephalopathy) roadmap. URL: http://europa.eu.int/comm/food/food/biosafety/bse/roadmap_en.pdf, 2005) as the main condition for lifting the extended feed ban. Methods based on polymerase chain reaction (PCR) seem to be a promising solution for this aim. The main objective of this study was to determine the applicability of four different real-time PCR methods, developed by three National expert laboratories from the European Union (EU), for the detection and identification of cattle or ruminant species in typical compound feeds, fortified with meat and bone meals (MBM) from different animal species at different concentration levels. The MBM samples utilized in this study have been treated using the sterilization condition mandatory within the European Union (steam pressure sterilization at 133 degrees C, 3 bar, and 20 min), which is an additional challenge to the PCR methods evaluated in this study. The results indicate that the three labs applying their PCR methods were able to detect 0.1% of cattle MBM, either alone or in mixtures with different materials such as fishmeal, which demonstrates the improvement made by this technique, especially when compared with results from former interlaboratory studies.     

Agroforestry systems recover tree carbon stock faster than natural succession in Eastern Amazon,Brazil

Agroforestry Systems - The potential of agroforestry systems (AFS) for atmospheric carbon sequestration in degraded tropical lands is of key interest for climate change and rural development...     

N transformation mechanisms and N dynamics of organic fertilisers as partial substitutes for chemical fertilisers in paddy soils

Journal of Soils and Sediments - Knowledge of nitrogen (N) dynamics of organic fertilisers as partial substitutes for chemical fertilisers could improve the retention of mineral N and optimise...     

Connectedness of habitat fragments boosts conservation benefits for butterflies,but only in landscapes with little cropland

Landscape Ecology - Global change pressures (GCPs) imperil species and associated ecosystem functions, but studies investigating interactions of landscape-scale pressures remain scarce. Loss of...     

Oxidative degradation of lipids during mashing

Although hardly any polyunsaturated fatty acids (PUFAs) are present in the endproduct, the ingredients used for the production of beer contain a high concentration of PUFAs, such as linolic and linolenic acid. These compounds are readily oxidized, resulting in the formation of lipid-derived products that reduce the taste and quality of beer enormously. During mashing relatively high amounts of PUFAs are exposed to atmospheric oxygen at a relatively high temperature. This makes mashing a critical step in the brewing process with regard to the formation of lipid-derived off-taste products. F1 phytoprostane (PPF1) changes in antioxidant capacity and monohydroxy fatty acids (OH-FAs) were used as markers for the detection of oxidative damage to fatty acids during mashing. The pattern of OH-FA formation indicates that enzymatic oxidation of PUFAs is more important than nonenzymatic oxidation during the mashing process. Nevertheless, substantial nonenzymatic radical formation is evident from the increase of specific OH-FAs and PPF1s. It was found that a low oxygen tension reduces oxidative damage and gives a high antioxidant capacity of the mashing mixture. This indicates that mashing should be done under low oxygen pressure.     

Methods for evaluating human impact on soil microorganisms based on their activity,biomass, and diversity in agricultural soils

The present review is focused on microbiological methods used in agricultural soils accustomed to human disturbance. Recent developments in soil biology are analyzed with the aim of highlighting gaps in knowledge, unsolved research questions, and controversial results. Activity rates (basal respiration, N mineralization) and biomass are used as overall indices for assessing microbial functions in soil and can be supplemented by biomass ratios (C : N, C : P, and C : S) and eco‐physiological ratios (soil organic C : microbial‐biomass C, qCO₂, qN_min). The community structure can be characterized by functional groups of the soil microbial biomass such as fungi and bacteria, Gram‐negative and Gram‐positive bacteria, or by biotic diversity. Methodological aspects of soil microbial indices are assessed, such as sampling, pretreatment of samples, and conversion factors of data into biomass values. Microbial‐biomass C (µg (g soil)^–1) can be estimated by multiplying total PLFA (nmol (g soil)^–1) by the F_PLFA‐factor of 5.8 and DNA (µg (g soil)^–1) by the F_DNA‐factor of 6.0. In addition, the turnover of the soil microbial biomass is appreciated as a key process for maintaining nutrient cycles in soil. Examples are briefly presented that show the direction of human impact on soil microorganisms by the methods evaluated. These examples are taken from research on organic farming, reduced tillage, de‐intensification of land‐use management, degradation of peatland, slurry application, salinization, heavy‐metal contamination, lignite deposition, pesticide application, antibiotics, TNT, and genetically modified plants.     

Earthworm burrowing behaviour in 2D terraria with single- and multi-species assemblages

Experiments were performed in 2D terraria to investigate the burrowing behaviour of different earthworm species from various ecological categories in single- and multi-species assemblages. The burrowing behaviour was quantified using image analysis software during a 2-week period. Terraria were found to reveal realistic impressions of the burrowing behaviour of various species according to the ecological classification of Bouché into epigeic, endogeic and anecic species. Results of the study also permit the recommending of classifying various earthworms as intermediate species, e.g. Aporrectodea longa as endo-anecic and Lumbricus rubellus as epi-endogeic. Burrowing activity of endogeic species was significantly reduced in multi-species compositions compared to single-species treatments. Moreover, burrowing activity of Octolasion tyrtaeum was significantly reduced in the presence of Lumbricus terrestris compared to the specific single treatment. This endogeic species profited from the burrowing behaviour, e.g. bioturbation, of L. terrestris, and as such this is circumstantial evidence for commensalism (species interaction, in which one partner benefits while the other is unaffected) between anecic and endogeic earthworm species. Simultaneous burrowing activity of a combined assemblage of both endogeic species, Aporrectodea caliginosa and O. tyrtaeum, was also significantly reduced compared with the particular single treatments. Thus, this seems likely to be a response of interspecific competition and trophic niche separation between endogeic species.