نتایج جستجو برای: top soil

تعداد نتایج: 304166  

2009
R. E. Arvidson R. G. Bonitz M. L. Robinson J. L. Carsten R. A. Volpe A. Trebi-Ollennu M. T. Mellon P. C. Chu K. R. Davis J. J. Wilson A. S. Shaw R. N. Greenberger K. L. Siebach T. C. Stein S. C. Cull W. Goetz R. V. Morris D. W. Ming H. U. Keller M. T. Lemmon H. G. Sizemore M. Mehta

[1] The Mars Phoenix Lander was equipped with a 2.4 m Robotic Arm (RA) with an Icy Soil Acquisition Device capable of excavating trenches in soil deposits, grooming hard icy soil surfaces with a scraper blade, and acquiring icy soil samples using a rasp tool. A camera capable of imaging the scoop interior and a thermal and electrical conductivity probe were also included on the RA. A dozen tren...

Journal: :Environmental microbiology 2009
Kristen R Freeman Monte Y Pescador Sasha C Reed Elizabeth K Costello Michael S Robeson Steven K Schmidt

Soil-dominated ecosystems, with little or no plant cover (i.e. deserts, polar regions, high-elevation areas and zones of glacial retreat), are often described as 'barren', despite their potential to host photoautotrophic microbial communities. In high-elevation, subnival zone soil (i.e. elevations higher than the zone of continuous vegetation), the structure and function of these photoautotroph...

2017
Xinxin Chen Qishuo Ding Zbigniew Błaszkiewicz Jiuai Sun Qian Sun Ruiyin He Yinian Li

We investigated a method to quantify field-state wheat RSA in a phenotyping way, depicting the 3D topology of wheat RSA in 14d periods. The phenotyping procedure, proposed for understanding the spatio-temporal variations of root-soil interaction and the RSA dynamics in the field, is realized with a set of indices of mm scale precision, illustrating the gradients of both wheat root angle and elo...

Journal: :Journal of nematology 1973
J L Ruehle

Seedlings of longleaf pine (Pinus palustris) were grown in 20-cm pots for 5 to 7 months in the greenhouse following inoculation with a high or low level of one of seven species of plant-parasitic nematodes. Belonolaimus longicaudatus and Helicotylenchus dihystera had no effect on seedling growth. High inoculum densities of Hoplolaimus galeatus and Tylenchorhynchus claytoni caused a significant ...

Journal: :American journal of public health 2001
W P Eckel M B Rabinowitz G D Foster

OBJECTIVES Our objective was to enumerate unrecognized former lead smelters in the United States. METHODS Defunct smelters were identified by historical research. The compiled list was compared with government registries of hazardous sites. Soil samples were taken from 10 sites. RESULTS Approximately 430 sites were unknown to the federal authorities. Only 5 of 319 sites were known to author...

Journal: :Journal of nematology 1977
R S Hussey

Subsoiling to a depth of 35 cm under the planting row for 3 consecutive years increased annual yields of seed cotton by 50 to 200%. Annual subsoiling was essential for maximum yields. The application of a nematicide, 1,2-dibromo-3-chloropropane (DBCP) or aldicarb, reduced the population of Hoplolaimus columbus but did not increase seed-cotton yields over subsoiling alone. Subsoiling reduced H. ...

2012
Jie Wei Jimin Cheng Weijun Li Weiguo Liu

Vegetation restoration has been conducted in the Chinese Loess Plateau (CLP) since the 1950s, and large areas of farmland have been converted to forest and grassland, which largely results in SOC change. However, there has been little comparative research on SOC sequestration and distribution between secondary forest and restored grassland. Therefore, we selected typical secondary forest (SF-1 ...

2014
Long Yang Jun Wang Yuhui Huang Dafeng Hui Meili Wen

For the purposes of forest restoration, carbon (C) fixation, and economic improvement, eucalyptus (Eucalyptus urophylla) has been widely planted in South China. The understory of eucalyptus plantations is often occupied by a dense community of the fern Dicranopteris dichotoma, which intercepts tree canopy leaf litter before it reaches the ground. To understand the effects of this interception o...

2014
R. Ziaie Moayed M. Alibolandi

Dynamic behavior of soil are evaluated relative to a number of factors including: strain level, density, number of cycles, material type, fine content, geosynthetic inclusion, saturation, and effective stress .This paper investigate the dynamic behavior of saturated reinforced sand under cyclic stress condition. The cyclic triaxial tests are conducted on remolded specimens under various CSR whi...

Journal: :Journal of nematology 1981
A W Johnson J R Young B G Mullinix

Phenamiphos, ethoprop, and carbofuran each at 6.7 kg a.i./ha were applied to squash, southern pea, and corn via injection into a sprinkler irrigation system. This method was then compared with a conventional application of phenamiphos and ethoprop granules spread on the soil surface and incorporated into the top 15 cm for control of Macroposthonia ornata and Meloidogyne incognita. Nematode popu...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید