Effects of leaf litter tannin on soil ammonium and nitrate content in two different forest soils of mount Wuyi, China

Penicillium spp. predominated in samples of forest soils except occasionally at depths of more than three inches, when Mucor and Aspergillus spp. sometimes were more abundant. Incubation for 30 days at 28 °C and 50 per cent water-holding capacity frequently increased the percentage of Mucor spp. as well as Penicillium spp. Mucor spp. were consistently more prominent in soils associated with alder than for other coastal soils. Mucor and Aspergillus spp. also appeared often in soil from stands of ponderosa pine growing east of the Cascades.The greatest concentration of nitrogen as NO3− in unincubated soils was found in a young red alder stand. Samples of soil from stands of virgin coastal redwood showed no nitrate nitrogen. Soils from stands of virgin Sitka spruce, however, showed considerable nitrate content, which increased markedly with incubation.With few exceptions, bacteria and actinomycetes were most numerous in F layers of soil. Incubation greatly increased these populations in most soils.

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Ways of improving the use of photosynthetically active radiation in potato cultivation in the middle Volga steppe

Vestnik of Kazan state agrarin university ◽

10.12737/2169 ◽

2014 ◽

Vol 8 (4) ◽

pp. 103-108

Author(s):

Владимиров ◽

Sergey Vladimirov

Keyword(s):

Leaf Area ◽

Mineral Nutrition ◽

Forest Soils ◽

Starch Content ◽

Nitrate Content ◽

Potato Tubers ◽

Potato Leaf ◽

Gray Forest Soils ◽

Photosynthetic Potential ◽

Middle Volga

The efficacy of using the calculated doses of fertilizers for upcoming harvests potatoes was studied. As a result of studies of the potato leaf area formation dynamics on gray forest soils of the Middle Volga steppe, its dependence on mineral nutrition level was revealed. Their impact on productivity and quality of potato tubers was identified. The efficacy of calculated doses of fertilizers for upcoming potato harvests were studied. Fertilizing crops by scheduled doses, counted by cash- balance method for upcoming yields of 25-40 tons per hectare, provided the formation of 90,5-98,0% of the target yield. The nitrate content in all versions of the experiment was below the maximum admissible concentration. However, with increasing fertilizers amount, their content was increased in 1,24-1,73 times (without fertilizers - 41 mg / kg of wet weight). As a result of studies of the dynamics of potato leaf area formation on gray forest soils of the Middle Volga steppe, we revealed its dependence on mineral nutrition level. The photosynthetic potential (PP) during the growing season of potato Udacha, was in the first version without fertilizers 2.173, the second 2.520, in the third 2.910, fourth 3.196 and fifth 3.575 million square meter per hectare * days, i.e. with an increase in fertilization rates, the photosynthetic potential increased accordingly to 0.347-1.402 million units, for every thousand units of photosynthetic potential we obtained from 7.2 to 10.8 kg potato tubers. A starch content varied from a few of fertilizers. The maximum starch content (14 %) was obtained in the second way, calculated on the tuber yield of 25 tons per hectare. A further increase in the background was led to some of its decline.

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Assessment of Aqueous Extraction Methods on Extractable Organic Matter and Hydrophobic/Hydrophilic Fractions of Virgin Forest Soils

Molecules ◽

10.3390/molecules26092480 ◽

2021 ◽

Vol 26 (9) ◽

pp. 2480

Author(s):

Wan Muhammad Ikram Wan Mohd Zamri ◽

Fridelina Sjahrir ◽

Nor Suhaila Yaacob ◽

Noor Fazreen Dzulkafli ◽

Mohd Fadzli Ahmad ◽

...

Keyword(s):

Organic Matter ◽

Forest Soils ◽

Extraction Methods ◽

Soil Extract ◽

Nitrate Content ◽

Soil Extraction ◽

Forest Reserve ◽

Soil Extracts ◽

Virgin Forest ◽

Extractable Organic Matter

The assessment of water-extractable organic matter using an autoclave can provide useful information on physical, chemical, and biological changes within the soil. The present study used virgin forest soils from Chini Forest Reserve, Langkawi Island, and Kenyir Forest Reserve (Malaysia), extracted using different extraction methods. The dissolved organic carbon (DOC), total dissolved nitrogen (TDN), total dissolved phosphorus (TDP), and ammonium-nitrate content were higher in the autoclave treatments, up to 3.0, 1.3, 1.2, and 1.4 times more than by natural extraction (extracted for 24 h at room temperature). Overall, the highest extractable DOC, TDN, TDP, ammonium and nitrate could be seen under autoclaved conditions 121 °C 2×, up to 146.74 mg C/L, 8.97 mg N/L, 0.23 mg P/L, 5.43 mg N mg/L and 3.47 N mg/L, respectively. The soil extracts became slightly acidic with a higher temperature and longer duration. Similar trends were observed in the humic and nonhumic substances, where different types of soil extract treatments influenced the concentrations of the fractions. Different soil extraction methods can provide further details, thus widening the application of soil extracts, especially in microbes.

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