Water and thermal regime of extensive green roof test beds planted with sedum cuttings and sedum carpets

Journal of Soils and Sediments - Implementation of green roofs could help to reduce rapid runoff and help cities to mitigate heat islands. The aim of the study is to assess the water and...     

A simple and easy method to measure ammonia volatilization: Accuracy under field conditions

Field studies on soil ammonia(NH₃)volatilization are restricted in many countries owing to the high costs commonly demanded for accurate quantification.We assessed the accuracy of a simple,open chamber design to capture NH₃under field conditions,as affected by different chamber placement schemes.Urea-15 N was surface applied to lysimeters installed in the spaces between maize rows.Open chambers made from plastic bottles were installed on each lysimeter with variations in i)N rates(3,8,13,and 18 g m^-2),ii)the height of the chamber above the soil surface(0,5,and 10 mm),and iii)chamber relocation(static vs.dynamic).Reference lysimeters without chambers were used to measure NH₃losses by¹⁵N-balance.Losses of NH₃-N accounted for more than 50%of the applied N.Relocation of the chambers had no impact on their NH₃-trapping efficiencies,proving to be an unnecessary procedure.Variation in the height of the chambers above the soil surface affected the capture of NH₃,but the results still maintained high linearity with the NH₃losses quantified by the reference method(R²>0.98).When the same placement scheme used in the introductory study describing the chamber was utilized(static and touching the soil surface),we found a trapping efficiency of 60%,which was very similar to that(57%)obtained in the previous study.Our results show that this simple,open chamber design can be used with satisfactory accuracy under field conditions,provided that simple,standardized procedures are warranted.     

The potential feasibility for soil improvement, based on the properties of biochars pyrolyzed from different feedstocks

Purpose

Biochars have been considered as useful soil amendments due to their beneficial properties in improving soil fertility, carbon (C) sequestration, and soil decontamination. In our study, a series of biochars produced from different types of feedstocks at two pyrolysis temperatures (300 and 500 °C) were characterized to evaluate their different potentials as soil amendments.

Materials and methods

Ten types of feedstocks were used to prepare biochars at the pyrolysis temperatures of 300 and 500 °C, for 2 h. Chemical and physical analyses, X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier Transform Infrared (FTIR) analyses were conducted to determine differences in biochar properties. Then, soil incubation studies were used to investigate the relationships between these biochar properties and their different ameliorant values in soil.

Results and discussion

The pH, ash, total C, total potassium, total phosphorus, total base cation concentrations, surface areas, and total pore volumes of biochars produced at 500 °C were higher than at 300 °C, while the reverse applied for yields, total oxygen and total hydrogen, and average pore widths and particle sizes. Cluster analysis suggested that biochars derived from similar feedstock types belonged in the same category. The SEM, XRD, and FTIR analyses of typical biochars from the different categories suggested both variations and similarities in their characteristics. In addition, the results from soil incubation experiments were consistent with the conclusions made from biochar characteristics analysis.

Conclusions

Biochars derived from swine manures, fruit peels, and leaves with high pH and macro-nutrients appeared appropriate to increase soil pH and soil nutrient availability; whereas, biochars from wetland plant residues with high C concentrations and Brunauer–Emmett–Teller were better for soil C sequestration and contaminant adsorption.     

Otter havens in norfolk & suffolk,England

The aims and basic principles underlying the establishment of otter havens are set out. Two types are described, one giving maximum protection to both the otter and its habitat (M Areas) and the other less rigid protection in areas where the habitat is not so suitable owing to lack of cover (P Areas).River management is discussed and the conclusion drawn that the establishment of otter havens is likely to be practical and effective only in the upper, privately owned stretches of a river, although public bodies may be encouraged to keep the otter's needs in mind when planning works on the lower, publicly owned and navigable stretches.The successful establishment of havens requires the co-operation of riparian owners, farmers, fishing interests, the Regional Water Authority and Internal Drainage Boards.The procedure adopted by the Otter Trust in succesfully establishing havens on three river systems in East Anglia is described and details given for the Rivers Waveney, Wissey and Thet. The importance of regular monitoring of otter movements before and after the establishment of havens is stressed.It is emphasised that the establishment of otter havens is a long term action with little possibility of quick results. Furthermore the techniques developed are still in the experimental stage and only time and regular monitoring combined with population surveys will show whether they can make a practical contribution towards otter conservation. Freedom from disturbance and plenty of cover are the key factors for a successful haven.     

仔猪饮水和体重的关系

对仔猪来说 ,吃和喝是紧密相连的。若没有足够的饮水 ,是很难使仔猪吃下大量干饲料的。遗憾的是 ,许多养猪者都没有认识到清洁而方便的饮水源对于仔猪有多么重要。     

INTRACRANIAL INTRA-ARACHNOID CYST WITH INTRACYSTIC HEMORRHAGE IN TWO DOGS

Clinical signs, magnetic resonance imaging (MRI) features, treatment, and outcome of two adult dogs with neurologic dysfunction resulting from hemorrhage into a quadrigeminal intracranial intra-arachnoid cyst are described. In dog 1, the cyst was hyperintense to cerebrospinal fluid (CSF) on T1-weighted MRI and hypointense to CSF on T2-weighted images. In dog 2, the cyst was isointense to CSF on T1- and T2-weighted images. Both dogs were treated with craniotomy and cyst fenestration. A large blood clot was removed from the lumen of the cyst in each dog. Dog 1 is clinically normal 3.5 years post-surgery and has a persistent cyst. Dog 2 had a good initial response to therapy but was euthanized 2.5 years post-operatively due to generalized seizures. The late onset of clinical signs in these dogs most likely resulted from hemorrhage into the cyst. Surgical fenestration and hematoma removal appear to provide a satisfactory treatment for adult dogs with an intracranial intra-arachnoid cyst and intracystic hemorrhage. Persistence of the cyst may occur in some dogs.     

Persistent Hyperammonemia in Two Related Morgan Weanlings

Persistent hyperammonemia was diagnosed in 2 Morgan fillies with clinical signs that developed early in the post-weaning period. Diagnostic evaluation, including routine serum chemistries, CBC, liver biopsy, hepatic ultrasonography, liver function test, and necropsy findings did not support a toxic, developmental, or infectious cause. Abnormal serum amino acid and urine orotic acid concentrations suggest that the foals may have had an inherited disorder, described in humans as hyperornithinemia, hyperammonemia, and homocitrullinuria (HHH) syndrome. The disorder is thought to be caused by a defective mitochondrial transporter protein, such that ornithine, required for complete urea synthesis, is deficient, thus causing increases in blood ammonia and ornithine concentrations.