Measuring and interpreting the temporal variability in the soundscape at four places in Sequoia National Park

The soundscape was recorded in four selected places in Sequoia National Park CA, to quantify and assess the diurnal and seasonal character of the park’s soundscape. The recording sites were selected to represent a combination of elevation and vegetation diversity. Hour-long sound recordings were made by four individuals at each place during fall, spring, summer and winter at dawn, midday, dusk, and midnight with identical recording instrumentation. The recordings of the soundscape were made in an old growth forest (Crescent Meadow), in a foothill oak savanna (Sycamore Spring), in an upland savanna chaparral (Shepherd Saddle) and in a foothill riparian location adjacent to the Kiawah River (Buckeye Flat). Sound recordings were analyzed using a normalized Power Spectral Density (PSD) algorithm and partitioned into 1 kHz intervals based on 12 subsamples from each of the 64 h-long sound recordings. Biological signals (biophony) were based on the highest PSD value within the range of 2–8 kHz. A multilevel analysis (MLA) was used to examine temporal patterns of biophony at four locations in Sequoia National Park. Unsupervised Landsat Thematic Mapper Satellite Imagery identified 25 vegetation regimes in Sequoia National Park. Satellite signatures of the habitat where recordings were made were extracted from the imagery to scale to the region.     

Linking Organic Carbon,Water Content,and Nitrous Oxide Emission in a Reclaimed Coal Mine Soil

Mine‐land reclamation for biomass production is often achieved by means of large applications of N and organic C with amendments that could create soil conditions favorable for N₂O production and emissions. To investigate this possibility, we conducted a laboratory experiment using mine soil collected from an active surface coal mine site near Philipsburg, Pennsylvania. During a 37‐d incubation period, we measured N₂O and CO₂ fluxes from non‐amended soil and from soil amended with ammonium nitrate (L + F), composted poultry manure (Comp), poultry manure alone (Man) and mixed with 3 rates of paper mill sludge (PMS) to obtain carbon to nitrogen ratios of 14, 20 and 27 (Man + PMS14, 20 and 27), each at 60% and 80% water filled pore space (WFPS). Results showed that manure alone leads to a greater emission of N₂O under laboratory conditions than with L + F. However, composting manure effectively reduced the emissions compared to that of L + F despite a large addition of organic C and N. Composted manure‐treated soil emitted less than all other manure‐based treatments at both 60% and 80% WFPS. The emissions were greater from soil amended with the Man + PMS treatments compared to non‐amended and L + F‐amended soil, and it increased during periods of intense microbial activity created by the application of manure and PMS. Higher water content increased emissions particularly during periods of intense microbial activity coupled with inorganic N availability. Cumulative N₂O emissions from manure‐treated soils represented less than 0·1% loss of total applied N. Copyright © 2014 John Wiley & Sons, Ltd.     

Nitrous Oxide Emissions from a Coal Mine Land Reclaimed with Stabilized Manure

Mine‐soil treatment using stabilized manure rapidly sequesters large quantities of organic carbon and nutrients. However, the nutrient‐rich soil conditions may become highly conducive for production and emission of N₂O. We examined this possibility in a Pennsylvania coal mine restored using poultry manure stabilized in two forms: composted (Comp) or mixed with paper mill sludge (Man + PMS) at C/N ratios of 14, 21, and 28 and compared those with the emissions from conventionally treated soil. The mine soil was extremely well drained with 59% coarse fragments. Soil–atmosphere exchange of N₂O and CO₂ was determined using a sampling campaign of ten measurements between 16 June and 14 September 2009 (90 days) and 13 measurements between 28 June and 9 November 2010 (134 days) using static vented chambers at ambient and increased moisture (water added) content. Potential denitrification was determined in a laboratory incubation experiment. While non‐amended mine soil did not have a measurable potential for denitrifying activity, the manure‐based amendments introduced the potential. Soil water filled pore space was less than 60% on most sampling days in both ambient and water‐added plots. Daily N₂O‐N emissions ranged between 40 and 70 g N ha⁻¹ with cumulative emissions of 2–4 kg N ha⁻¹ from non‐amended, lime and fertilizer (L + F) and Comp, and 3–10 kg N ha⁻¹ from Man + PMS treatments. The maximum emission obtained from Man + PMS represented <1% loss of applied N. Although stabilized manure‐treated soil exhibits the potential for N₂O production, the emission is limited when soils are excessively well drained and reducing conditions rarely develop. Copyright © 2015 John Wiley & Sons, Ltd.     

赤桉、尾叶桉接种外生菌根菌的效果分析

在广东省阳西县开展赤桉和尾叶桉接种10个外生菌根菌的野外试验，根据造林后对树高、地径和胸径的观测，发现菌根菌与树种间存在互作效应，这种效应影响菌根菌接种效果；试验筛选出的菌株：H4461，适于尾叶桉，树高增加2％－21％，胸径增加13％－35％，对赤桉树高生长也有促进作用；H4339，对赤桉1年生内幼树树高生长有显著促进作用， 也改善径生长，也适用于尾叶桉；H4111，对赤桉、尾叶桉的后期生长有效果；E4100、H4331、H4338和H4317，有时对参试树种生长有改善作用；其它参试菌根菌E4070，H4937，H4314，在两树种间表现极不稳定。     

施P肥和外生菌根菌接种对蓝桉林产量和养分积累的影响

主要研究施P肥和接种外生菌根菌对蓝桉生长、生物量和养分积累的影响。在云南楚雄的试验表明：接种外生菌根菌只能在幼林期促进树木生长，3a后这种促进作用不显著。施P肥能在幼林期促进蓝桉树高和胸径的生长，但4．5a后这种促进作用也变得不显著。由于施P肥提高了蓝桉的保存率，所以也显著地提高了蓝桉林的生物量。低P处理时，树木保存率低，较大的生长空间促进了树木的后期生长，可能会导致施P肥对后期单株蓝桉树高和胸径生长作用不显著。施P肥还增加了树木N、P和K的养分积累量，提高了上述养分的利用效率。施P肥同时还明显增加了林下植被和林下凋落物P的积累量，但不能明显增加N和K的养分积累量。树木叶片和土壤分析结果进一步说明施P肥对蓝桉幼林作用明显。试验表现出接种外生菌根菌只能在低P情况下促进树木生长，不能在高P情况下促进树木生长的基本趋势。     

Leaf growth, photosynthesis and tissue water relations of greenhouse-grown Eucalyptus marginata seedlings in response to water deficits

Leaf growth, rate of leaf photosynthesis and tissue water relations of shoots of Eucalyptus marginata Donn ex Sm. (jarrah) seedlings were studied during a soil drying and rewatering cycle in a greenhouse experiment. Rates of leaf growth and photosynthesis were sensitive to water deficits. The rate of leaf growth decreased linearly with predawn leaf water potential to reach zero at -1.5 MPa. Rate of leaf growth did not recover completely within the first three days after rewatering. Midday photosynthetic rates declined to 40% of those of well-watered seedlings at a predawn leaf water potential of -1.0 MPa and reached zero at -2.2 MPa. Photosynthetic rate recovered rapidly following rewatering and almost fully recovered by the second day after rewatering. All tissue water relations parameters, except the bulk modulus of elasticity, changed significantly as the soil dried and recovered completely by the third day after rewatering. Changes in osmotic pressure at full turgor of 0.4 MPa indicated considerable capacity for osmotic adjustment. However, because there was little osmotic adjustment until predawn leaf water potential fell below -1.5 MPa, this capacity would not have enhanced seedling growth, although it may have increased seedling survival. The sensitivity of photosynthesis and relative water content to water deficits suggests that greenhouse-grown E. marginata seedlings behave like mesophytic plants, even though E. marginata seedlings naturally grow in a drought-prone environment.     

Nitrogen Fertilizer Increases Seed Protein and Milling Quality of Rice

Rice grain breakage during milling is a problem in many parts of Asia. It has been suggested that nitrogen (N) fertilizer can improve the milling quality of rice. Therefore, this study investigates effects of N fertilization on grain N concentration, endosperm storage protein distribution, and milling quality of rice. Four Thai extra long grain commercial rice cultivars (KDML105, KLG1, PTT1, and CNT1) were grown at Chiang Mai University in the wet season of 2001 with 0 or 120 kg of N/ha at flowering. Anatomical sections showed that there was more storage protein accumulated in the lateral regions of polished grain of high N concentration than in grain of low N concentration. Percent (%) unbroken rice was positively correlated with relative abundance of storage protein in the lateral region of the endosperm in all cultivars. Applying N increased head rice N concentration in all cultivars, whereas % unbroken rice was increased in KLG1 and CNT1. KDML105 cultivar, on the other hand, already had high % unbroken rice and more abundant storage protein in the lateral region with the grain of low N concentration. It is hypothesized that high density of storage protein in the lateral region of the endosperm provides resilience and lessens grain breakage during milling. The additional protein may increase hardness in rice grains and thus could make the rice more resistant to breakage during milling. Furthermore, N fertilization may enhance the nutritional quality of rice grain by increasing the glutelin content, which is rich in lysine.     

Time trends in mortality of Conophthorus ponderosae (Hopkins) exposed to insecticide residues

The protection of the female cones of Pinus monticola (Dougl. ex D. Don) from attack by Conophthorus ponderosae (Hopkins) requires that the beetles be killed before they enter the cone. This encourages consideration of the distributions of length of time to death and how these distributions are changed with different concentrations of various candidate insecticides. In this study a three-parameter Weibull function was employed to depict the distributions for data originally collected for a probit analysis. The time to achieve 90% mortality as defined by the Weibull function was taken as a dependent variable, and a regression evaluation was used to define relationships with concentration for selected insecticides. The mode Y = b0 + b1 · X⁻1, in which Y = LT90 and × = insecticide concentration in g litre⁻1, proved useful when a sufficient range of concentrations was included in the testing.