Litter Moisture

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Preliminary results of statistical analysis focused on the dependence between forest litter moisture and relative air humidity

Preliminary results of statistical analysis focused on the dependence between forest litter moisture and relative air humidity

In the first case (Fig. 7a), the measurements were done on the flatland. In this case the largest range of litter moisture values was at 3.00 PM. In case of morning measurements we can see that the values did not vary to such an extent. Their variability was even smaller than that of litter moisture measure- ments in the evening. It is so because that during the day when it was warmer, the moisture content decreased in the upper layer of the litter, which made this moisture move towards the lower layers. And that is the reason, why there is a large range of values. In the second case (Fig. 7b), we used the correlation coefficient values for the site with the slope of 10°. There is a small difference in measure- ments during the day. This can be caused by the fact that in the sites with steeper terrain slope the change in the moisture content is more propor- tional than on the flatland. This is a logical result that can be explained by higher runoff caused by a rain event downward the slope and not towards the next layer like on the flatland. The box graph in Fig. 7c shows the values measured at the steepest site, where the terrain slope was 20°. Here the situ- ation is similar to that documented in the previous graph. Similarly, the range of correlation coefficient values is narrower than in the case of the flatland.

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Comparison of different methods for the in situ measurement of forest litter moisture content

Comparison of different methods for the in situ measurement of forest litter moisture content

Despite relatively wet weather conditions and generally low fire danger, different sensors for the determination of lit- ter moisture could be tested and valuable insights gained. All sensors showed erratic behavior at very high litter mois- ture contents; however, they are not relevant for forest fire applications as these conditions are not linked to fire dan- ger and may not even occur in more fire-prone regions. While significant correlations and regressions between the rescaled sensor raw values and gravimetrically determined litter moisture could be obtained for all sensors tested, sig- nificant differences between the regressions for periods 1 and 3 (in March/April and June/July, respectively) suggest that changes over time within the litter layer affect the sensor’s raw value–litter moisture relationship. Thus, sensors should not be calibrated only once in situ directly after installation. In contrast, relatively frequent recalibration (e.g., at least ev- ery 2 or 3 months) is necessary. Additionally, more work on the precise fine-tuning of the very poor performing resistance sensors would have to be done if this measuring technique were to be used. However, their generally limited measuring range should be considered.

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Effect of Dietary Electrolyte Balance on Water Intake, Litter Moisture and Production of Broiler chicks at Pre Starter and Starter Phases

Effect of Dietary Electrolyte Balance on Water Intake, Litter Moisture and Production of Broiler chicks at Pre Starter and Starter Phases

Underestimating the negative impacts of ammonia produced in litters of poul- try birds raised under high temperature-humidity index is dangerous, as broiler chickens (BC) are sensitive to high ammonia concentrations which can result in blindness and overall decrease in productive performance. Hence, it is ideal to maintain litter moisture by optimizing the utilization of water by broiler chicks. The balance of acid-base in broilers could be enhanced by supplementing diets or water of BC under heat stress with electrolytes. However, electrolytes in- crease water intake and might affect litter quality. Therefore, effect of varying dietary electrolyte balance (DEB) on water intake (WI), litter moisture (LM) and productive performance of BC were investigated at pre-starter and starter phases using a total of three hundred, 1-day-old Arbor Acre chicks that were randomly allotted to six dietary treatments [210 (T 1 ), 240 (T 2 ), 270 (T 3 ), 300

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Water activity of poultry litter: Relationship to moisture content during a grow-out

Water activity of poultry litter: Relationship to moisture content during a grow-out

equilibrium conditions (constant temperature, no air velocity and no air exchange), which do not occur in commercial poultry sheds. If temperatures are unbalanced, with the litter surface being below the dewpoint temperature, then water will also condense on the litter surface (Tucker and Walker, 1992). Additionally, the effect of increasing air velocity in the poultry shed may reduce water ab- sorption into the litter surface, resulting in lower litter moisture content for a given relative humidity condition (Foong et al., 2009). It has been demonstrated that the microbiological properties of poultry litter are directly related to A w , and that maintaining litter

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Water addition, evaporation and water holding capacity of poultry litter

Water addition, evaporation and water holding capacity of poultry litter

AS 3743-2003 (appendix B method) (Standards Australia, 2003) was used to determine the water holding capacity and porosity of litter samples. In brief, custom apparatus, as described in the Standard, was used comprising two pieces of PVC tube (internal diameter 8.7 cm, length 12.0 cm), one capped on the bottom and the second adapted so it could fi t snugly over the top of the fi rst piece (bottom tube and top tube, respectively). Drain holes were drilled in the bottom cap. The volume of the bottom tube was calibrated by fi lling the tube with water and gravimetrically determining the volume of water added. Litter was pre-conditioned to 45 – 55% moisture content and then poured into the top of the tube (both pieces joined together at this stage) until the top section was at least half full. The tubes and moist- ened litter were dropped 5 times from a height of 5 cm to settle the litter. The apparatus was soaked three times in a container of water so that the entire litter sample was completely submerged. The top section of tube and excess litter was carefully removed and the surface of litter levelled in the bottom tube. This was then lowered into water until water was level with the top surface of the litter and tube. The drain holes were blocked as the apparatus was removed from the water. Water was drained for up to 60 min into a pre-weighed container. The entire saturated litter sample was then poured into a pre-weighed sample dish and dried at 65 °C until it reached stable weight. Water holding capacity was calculated (Eq. (6)) in units L/m 2 assuming litter depth of 5 cm to enable direct comparison with water application rates calculated using Eq. (1). Litter moisture content when saturated was also calculated (mass of water/mass of litter sample, given as a percentage). Porosity was calculated using Eq. (7).

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Incubation and Nutritional Factors that Affect Footpad Skin Development and Dermatitis.

Incubation and Nutritional Factors that Affect Footpad Skin Development and Dermatitis.

However, when evaluating FPD at 28 d this parameter had a central role on FPD severity. The average±SD of litter moisture percentage for 13 and 28 d were 44.1±7.8 and 44.4±6.6 respectively, therefore no much variation of litter moisture content was observed between the two the evaluations. Furthermore, at 28 d age the effect of TEM treatments were no longer observed which can probably be due to the overcome effect litter moisture over the TEM treatments. When litter moisture was not controlled as covariate on the statistical analysis a trend (P=0.087) of incubation TEM was still observed. Again LH TEM chickens had worst FPD scores when comparing with S chickens. It was observed that when litter moisture was not controlled the probability of LH chickens to have paws with brown discoloration and ulceration was 3.26% and 3.85% respectively higher than S chickens. An interesting parameter to look at is the different response between birds incubated with the two TEM treatments to litter moisture. By the linear regression models (Figure V - 1) it was observed that for each litter moisture percentual increment the worsening on FPD score was higher in LH chickens when comparing with S chickens. The test of differences between slopes indicated a trend (P=0.13) on differences between the two TEM. Chickens incubated with LH TEM when exposed to 1% extra of litter moisture had an increase of 0.04 of FPD score. When looking to FPD scores of S chickens the FPD scores vary around half (0.02) of the LH chickens when increasing one unit of litter moisture. The minimum and maximum litter moisture values observed at 28 d were 32.5% and 57.8% respectively.

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Impact of Climate Change on Forest Fire Severity and Consequences for Carbon Stocks in Boreal Forest Stands of Quebec, Canada: a Synthesis

Impact of Climate Change on Forest Fire Severity and Consequences for Carbon Stocks in Boreal Forest Stands of Quebec, Canada: a Synthesis

The differences in forest floor drying pat- terns have important implications for spatial and temporal patterns of severe fire occur- rence. First, stands that have shallow forest floors (e.g., pine stands) have high drying rates of both litter and duff and will therefore be susceptible to deep burning early in the fire season when both litter and duff moisture con- tents are low. In these stands, the potential for high-severity fires is spread relatively uniform- ly during the fire season as it takes only a cou- ple of days without precipitation to create cir- cumstances prone to high-severity fire. In contrast, stands with thick forest floors (e.g., spruce stands), and thus a thick duff layer, dry substantially only at the end of the fire season, so deep burning is temporally limited to this period. Summer precipitation is likely to be less important than snowmelt for the deep duff moisture contents, but drying rates of litter in thick forest floors may be difficult to estimate. Data from Wotton and Beverly (2007) show a slightly higher litter moisture content in black spruce stands compared to equally dense pine stands under equal FFMC and DMC. Duff moisture variation is also found within stands as duff generally contains less water if posi- tioned under tree crowns compared to duff in gaps. Miyanishi and Johnson (2002) explained this as the result of the interception of precipi- tation and the lower amounts of dew formed under trees. This is reflected by the findings that duff consumption by fire often shows a patchy distribution, with the largest removal around tree bases that were alive at the time of fire. Nevertheless, Greene et al. (2007) attrib- uted this pattern to a lower heat loss to evapo-

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The role of rainfall and light interception by litter on maintenance of surface soil water content in an arid rangeland (Khabr National Park, southeast of Iran)

The role of rainfall and light interception by litter on maintenance of surface soil water content in an arid rangeland (Khabr National Park, southeast of Iran)

that are randomly placed within site. After determining the intensity of a typical storm of the region (20 mm/h), the rainfall duration required to saturate the litter from dry-weight to constant-weight is determined from the litter wetting curve. To plot the wetting curve, an outdoor rainfall simulator is used to wet the litter. Then drying curve of litter moisture content is determined from obtained field data with four replications. For measuring soil water content, three treatments are tested i.e. bare soil, soil with wetted litter and soil with dry litter. Average of the measured interception loss of four samples was 0.64% of this specific simulated rainfall (5.2 mm). This study clearly showed that rangeland litter decrease evaporation of the soil water content and light interception by litter have more important role in decreasing evaporation from the soil water content than the rainfall interception by litter.

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Effects of Physical Size of Clinoptilolite on Growth Performance, Serum Biochemical Parameters and Litter Quality of Broiler Chickens in the Growing Phase

Effects of Physical Size of Clinoptilolite on Growth Performance, Serum Biochemical Parameters and Litter Quality of Broiler Chickens in the Growing Phase

Proper environmental conditions are crucial for the performance of broiler chickens. Wet litter is an environment that supports bacterial and molds growth (Pappas et al., 2010). It is also the primary cause of ammonia emissions, one of the most serious environmental factors affecting broiler production. Controlling litter moisture is the most important step in avoiding ammonia problems. Clays and clay products, used as bedding material provide control over ammonia generation (McWard and Taylor, 2000; Tasistro et al., 2007). A study conducted by Olver (1997) showed that using zeolite causes a lower manure and litter moisture content. The adsorption property of zeolite has been widely used to combat litter problems. Kithome et al. (1999) indicated that zeolites were even suitable for reducing nitrogen losses during composting of poultry manure. In the present study, no significant differences were noted between treatments regarding the nitrogen content. But, there was a tendency to have drier litter conditions in the treatment with added clinoptilolite compared to the control diet. It is concluded that the supplementation of diet with clinoptilolite has positive effects on growth performance and litter moisture of broilers, but more research is required for the effect of physical size of clinoptilolite on boiler performance.

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The influence of litter age, litter temperature and ventilation rate on ammonia emissions from a broiler rearing facility

The influence of litter age, litter temperature and ventilation rate on ammonia emissions from a broiler rearing facility

At present, the European Union permits to keep broiler chickens on littered floor only (Council Directive 2007/43/EC, 2007). The way of bird keep- ing directly influences the pollution with danger- ous compounds, dust emissions and microbiological pollution on farms. Chemical pollutants are risk factors for the health of human beings and animals (Vaičionis et al., 2006). The piled up straw is gradual- ly enriched with excrements, rests of feed, water and feathers. Thus poultry manure is and starts to be the main source of ammonia emissions. Environmental features, such as bulk and surface temperature of the manure, influence ammonia volatilization with higher temperature resulting in increased ammonia volatilization (Richard et al., 2005). Litter moisture, which is mainly influenced by the ventilation and drinking system management, may affect the con- version rate of uric acid to ammonium nitrogen (Liu et al., 2006). All the above-mentioned factors are strongly influenced by litter age, i.e. by bird age. It has been reported that the emission rate of NH 3 increases with the flock age from the nearly zero value at the beginning of flock cycle to maximum values at its end (Gates et al., 2008).

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Kinetics of pyrolysis of litter materials from pine and eucalyptus forests

Kinetics of pyrolysis of litter materials from pine and eucalyptus forests

However, in order to simulate and study the gross features of forest fires, such as the rate of fire spread, time to ignition, etc., a single-step model for the pyrolysis reaction appears to be sufficient, and can be easily implemented through the current physics-based computational models [6, 17, 20]. The kinetics parameters observed for the forest fuel samples were obtained by employing the two commonly used methods, i.e. Flynn-Wall-Ozawa (FWO) and Kissinger-Akahire-Sunose (KAS) methods. The mass loss of composite litter shows an additive nature of the individual litter materials with an average deviation of 2%. Hence, using individual litter materials mass loss data can be used to construct a composite forest litter for analysis as litter composition varies over the timescale of months and years. Further, it was observed that the leafy part of forest litter materials, i.e. pine needles and eucalyptus leaves, behaved significantly differently to the bark and thin twigs at least in a qualitative sense.

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Valuation of ecosystem services in the organic carbon of the Pinus densiflora forest at Mt. Namsan, Seoul Metropolitan City

Valuation of ecosystem services in the organic carbon of the Pinus densiflora forest at Mt. Namsan, Seoul Metropolitan City

Another alternative that can be implemented for greenhouse gas reduction is to increase carbon fixation in forests. Forest ecosystems are major sink of carbon and account for about two-thirds of the total photosyn- thesis on the Earth. Approximately 80% of the land eco- system carbon and 40% of the soil carbon are stored in the form of aboveground and belowground biomass, dead tree, litter layer, and soil organic matter (Hu and Wang 2008; Dixon et al. 1994). In particular, organic carbon present as organic matter in forest ecosystems is related to the physical and chemical characteristics of soil, and the amount of organic carbon in soil is closely related to forest productivity and is important (Alban and Perala 1992). Forests provide public utility functions like biodiversity conservation, landscape preservation, and recreation services, along with its original function of wood production, and in particular, the importance of

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Automatic Cat Litter Cabinet

Automatic Cat Litter Cabinet

Cat litter is the material that uses by the breeders as a place for cats to disposes their feces. Within Malaysia, it has been estimate that the use of cat litter is very well received among cat breeders, especially those living in cities neighborhood areas. The process is simple; users need to fill the litter in the box or basin for cat to use and leave it. At a specific time, the breeders need to dispose the feces by scooping the feces manually. A litter box, sometimes called a sandbox, sand box, litter tray, litter pan, cat box, or cat box, is an indoor feces and urine disposal box for cats that are permitted free roam of a home but who cannot or do not always go outside to relieve themselves [1]. Many owners of these animals prefer not to let them roam outside for fear that they might succumb to the elements or get hit by a car, so a cat litter box makes it possible to shelter pets from these risks [1].

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Differences Of Basidiomycotina Types In Natural Forest Arboretum Gardens Unmul Samarinda

Differences Of Basidiomycotina Types In Natural Forest Arboretum Gardens Unmul Samarinda

environmental conditions tend to be very humid, the populations of the trees are dense and at least the intensity of the incoming sunlight, thus having the largest number of individuals compared to other transects due to the very humid conditions of the environment that support the growth of the fungus Basidiomycotina. The substrate type of the Basidiomycotina fungus found in Transect 1 is mostly in the litter, this is because the basidiomycotina fungus that grows in the litter is generally very easy to grow in areas that are protected from sunlight and high humidity conditions In Transect 2 in accordance with the vegetation analysis table, found 23 species included in 5 groups of families namely Bolbitiaceae, Tricholomataceae, Hydnaceae, Streaceae, And Poliporaceae. The type found with the highest percentage of individuals is Ganoderma applanatum. This is because the Ganoderma applanatum species are commonly found to grow on dried dead wood stump substrates, and the substrate type is commonly found in environmental types that are relatively low humidity and have considerable intensity of sunlight. In Transek 2, the environment is not too humid, much exposed to sunlight and the population of trees rarely makes the environmental conditions a bit drier than Transect 1 and Transect 3. The type of substrate of the fungus Basidiomycotina found in Transect 2 is mostly on tree trunks dry that has died. This is because the Basidiomycotina fungus that grows on dry stems of dead trees is generally easy to grow in areas that are exposed to sunlight and low humidity conditions. In Transect 3 according to the vegetation analysis table, 23 species were found in 7 family groups: Tremellaceae, Bolbitiaceae, Chantarellaceae, Tricholomataceae, Hydnaceae, Streaceae, and Poliporaceae

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Effects of Three Twice-A-Year Breeding Schedules in Four Breeds of Sheep

Effects of Three Twice-A-Year Breeding Schedules in Four Breeds of Sheep

Within breed heritabilities were estimated for conception rate, litter size at birth, litter weaning weight, litter weaning weight per ewe exposed, weaning weight and weaning weight adjusted for conception rate. Definitions of these traits were given in Pala et al. (2001). Data were analyzed with a derivative-free algorithm (Smith and Graser, 1986, Graser et al., 1987) using MTDFREML (Boldman et al., 1995). In addition, SAS V8 (SAS Institute Inc., 1999) was used for bootstrapping. REML procedures executed by SAS (1999) did not involve the relationship matrix. Convergence criterion was 1E-8 in both programs. To ensure global convergence, the algorithm by Boldman et al. (1995) was restarted with estimates until the log likelihood did not change at the fourth decimal.

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Nitrogen and Organic Matter Mineralization in the Tunisian Cork Oak Forest: A Laboratory Study

Nitrogen and Organic Matter Mineralization in the Tunisian Cork Oak Forest: A Laboratory Study

Mediterranean forests are subject to very restrictive conditions such as frequent drought conditions, higher temperatures and forest management practices that degrade the soil especially in the south part of the Mediter- ranean basin. Little has been investigated about soil C, N and microbial dynamics on organic matter decomposi- tion rates in such Mediterranean ecosystems. The overall objective of this study was to provide information about carbon and nitrogen mineralization in North of Africa especially in Tunisia. For this reason, we will ex- amine the effects of the variation of the soil water content and the addition of leaf litter on organic matter and nitrogen mineralization under the same laboratory conditions. This was achieved in three contrasting cork oak forests representative of one of the main forest ecosystems in the south part of the Mediterranean basin. Indeed, cork oak in Tunisia occupies a surface that represents approximately 50% of the area occupied by deciduous fo- rests and approximately 10% of the total forest area in Tunisia and about 5% of the area occupied by the world cork oak forests. In Tunisia, cork oak forests are at 80% in pure stands and at 20% mixed with zeen oak (Quer- cus canariensis Willd). In addition to their important hydrological and ecological roles, cork oak forests are subject to intense economic exploitation placing Tunisia among major cork producing countries.

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Chopped Bermuda Grass Hay as an Alternative Bedding Material for Rearing Market Turkey Hens

Chopped Bermuda Grass Hay as an Alternative Bedding Material for Rearing Market Turkey Hens

determined. Carcass grade and paw (foot) quality were not affected. Further studies were conducted in the field under commercial conditions (Bilgili et al., 2000; Hess et al., 2001). In multiple tests, broilers reared on sand performed as well as those reared on pine shavings. Foot pad quality and male broiler body weights were improved when reared on sand in some cases. Moisture and ammonia levels were similar to pine shavings with significantly lower levels of bacteria in the sand litter compared to shavings. Darkling beetle populations are reduced with sand litter. Growers using sand also wash the house once birds are marketed, the cake litter is removed thoroughly, sand added if needed, and then houses are set up for the next group of birds. However, this practice is not universal and may or may not prove to be practical. Certainly, sand litter would have to be totally removed in cases of disease out- breaks or if performance shows signs of a drop-off. Sand is currently under review in several areas of the country other than the south, with mixed results (Malone et al., 2001a; Malone et al., 2001b; Watkins, 2001a). While broiler performance was similar or better, in some cases, than for broilers reared on litter, some issues raised included poorer chick starts on sand compared to shavings and dustier air conditions. Other issues include sand used as litter is not cost effective for all farms, the economics of using sand may depend on location of sand versus the farm, and sand is not compatible with composting, combustion, or pelleting. Continued field trials will help determine the best management guidelines for using sand as litter.

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The effect of season and parity order on fertility of rabbit does and kit growth

The effect of season and parity order on fertility of rabbit does and kit growth

was registered in December, the highest number of dead kits occurred in this litter. Season also sig- nificantly affected (P ≤ 0.013) litter weight. The heaviest litters were in September and the lightest in April. It seems that during warmer months of the year the characteristics such as litter size and litter weight were negatively influenced. This is pre- sumably so because after winter does are in poorer health compared to the other months of the year. The effect of parity order on litter size was not sig- nificant. The lowest litter size was found in the first kindling and litter size gradually increased until the fifth kindling. Litter weight at 21 days (Table 3) was also found to be influenced by season and by parity order, the heaviest litters being in December. Litter weight increased until the third kindling, after which it declined. Significant interactions (P ≤ 0.005) were determined by this factor.

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Biomass allocation, shade tolerance and seedling survival of the invasive species Berberis darwinii (Darwin’s barberry)

Biomass allocation, shade tolerance and seedling survival of the invasive species Berberis darwinii (Darwin’s barberry)

Abstract: Berberis darwinii (Berberidaceae) is a serious environmental weed in New Zealand, capable of invading a range of different light environments from grazed pasture to intact forest. According to optimal partitioning models, some plants optimise growth under different environmental conditions by shifting biomass allocation among tissue types (e.g. roots, shoots) to maximise the capture of limiting resources (e.g. water, light). We examined patterns of growth, biomass allocation, and seedling survival in Berberis darwinii to determine whether any of these factors might be contributing to invasion success. Growth and biomass allocation parameters were measured on seedlings grown for 7 months in five natural light environments in the field. Survival was high in the sunniest sites, and low in the shadiest sites. Seedlings grown in full sun were an order of magnitude taller and heavier, had five times as many leaves, and proportionally more biomass allocated to leaves than seedlings grown in other light environments. In the shade, leaves were bigger and thinner, and leaf area as a proportion of total plant biomass increased, but the proportion of above- to below-ground biomass was similar across all light and soil moisture environments. In summary, although leaf traits were plastic, patterns of biomass allocation did not vary according to optimal partitioning models, and were not correlated with patterns of seedling survival. Implications for the management of this invasive species are discussed.

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Burning in a New Zealand snow-tussock grassland: Effects on vegetation and soil fauna

Burning in a New Zealand snow-tussock grassland: Effects on vegetation and soil fauna

The greatest increases (100 × at 16 months, 29 × at 30 months) were in Paratylenchus, a root-feeding genus widespread in tussock grasslands (Wood, 1973; Yeates, 1974). While the presence of germinating seedlings may have provided an additional food resource for this plant-feeding genus, its most apparent adaptive characteristic is the presence of a highly resistant subadult stage (Southey, 1978). It is considered that with the soil in the burned area less buffered from diurnal and seasonal temperature fluctuations and having a more variable moisture content [due in part to receiving less moisture input from mist (Rowley, 1970)], Paratylenchus is at an advantage in the burned area. Paratylenchus did not show significant differences from year to year. Helicotylenchus also feeds on plant roots, but lacks the resistant subadult stage. Populations of Helicotylenchus were 12 × and 4.8 × greater at the burned site on the two dates, and there was a significant difference between years (Table 4). Overall there was a significant increase in the root- associated Tylenchus which probably reflects greater rhizosphere activity. The overall significant decrease in the root-feeding Pratylenchus probably reflects the more variable environment of the exposed ground and the relative competitive advantage of Paratylenchus under these conditions. The bacterial feeding taxa Aphanolaimus, Rhabditidae and Cephalobus also showed significant overall increases in the burned plots; these changes are similar to those in bacterial-feeding nematodes

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